Objective: DNA damage response(DDR) deficiency has emerged as a prominent determinant of tumor immunogenicity. This study aimed to construct a DDR-related immune activation(DRIA) signature and evaluate the predictive ...Objective: DNA damage response(DDR) deficiency has emerged as a prominent determinant of tumor immunogenicity. This study aimed to construct a DDR-related immune activation(DRIA) signature and evaluate the predictive accuracy of the DRIA signature for response to immune checkpoint inhibitor(ICI) therapy in gastrointestinal(GI) cancer.Methods: A DRIA signature was established based on two previously reported DNA damage immune response assays. Clinical and gene expression data from two published GI cancer cohorts were used to assess and validate the association between the DRIA score and response to ICI therapy. The predictive accuracy of the DRIA score was validated based on one ICI-treated melanoma and three pan-cancer published cohorts.Results: The DRIA signature includes three genes(CXCL10, IDO1, and IFI44L). In the discovery cancer cohort, DRIA-high patients with gastric cancer achieved a higher response rate to ICI therapy than DRIA-low patients(81.8% vs. 8.8%;P < 0.001), and the predictive accuracy of the DRIA score [area under the receiver operating characteristic curve(AUC) = 0.845] was superior to the predictive accuracy of PD-L1 expression, tumor mutational burden, microsatellite instability, and Epstein–Barr virus status. The validation cohort demonstrated that the DRIA score identified responders with microsatellite-stable colorectal and pancreatic adenocarcinoma who received dual PD-1 and CTLA-4 blockade with radiation therapy. Furthermore, the predictive performance of the DRIA score was shown to be robust through an extended validation in melanoma, urothelial cancer, and pan-cancer.Conclusions: The DRIA signature has superior and robust predictive accuracy for the efficacy of ICI therapy in GI cancer and pancancer, indicating that the DRIA signature may serve as a powerful biomarker for guiding ICI therapy decisions.展开更多
Background:Phototherapies based on sunlight,infrared,ultraviolet,visible,and laser-based treatments present advantages like high curative effects,small invasion,and negligible adverse reactions in cancer treatment.We ...Background:Phototherapies based on sunlight,infrared,ultraviolet,visible,and laser-based treatments present advantages like high curative effects,small invasion,and negligible adverse reactions in cancer treatment.We aimed to explore the potential therapeutic effects of blue light emitting diode(LED)in human hepatoma cells and decipher the underlying cellular and molecular mechanisms.Methods:Wound healing and transwell assays were employed to probe the inhibition of the invasion and migration of hepatocellular carcinoma cells in the presence of blue LED.The sphere-forming test was used to evaluate the effect of LED blue light irradiation on cancer stem cell properties.Immunofluorescence and western blotting were used to detect the changes inγ-H2AX.The Cell Counting Kit-8 assay,5-ethynyl-2′-deoxyuridine staining,and colony formation assay were used to detect the combined effect of blue LED and sorafenib on cell proliferation inhibition.Results:We demonstrated that the irradiation of blue LED light in hepatoma cells could lead to cell proliferation reduction along with the increase of cell apoptosis.Simultaneously,blue LED irradiation also markedly suppressed the migration and invasion ability of human hepatoma cells.Sphere formation analysis further revealed the decreased cancer stemness of hepatoma cells upon blue LED irradiation.Mechanistically,blue LED irradiation significantly promoted the expression of the phosphorylation of the core histone protein H2AX(γ-H2AX),a sensitive molecular marker of DNA damage.In addition,we found that the combined treatment of blue LED irradiation and sorafenib increased cancer cell sensitivity to sorafenib.Conclusion:Collectively,we demonstrated that blue LED irradiation exhibited anti-tumor effects on liver cancer cells by inducing DNA damage and could enhance chemosensitivity of cancer cells,which represents a potential approach for human hepatoma treatment.展开更多
This study examined the role of PI3K/Akt pathway in radiosensitization of DNA damage of cervical carcinoma cells.The 50% inhibition concentration(IC50) of cisplatin and docetaxel in HeLa cells was detected by Mono-nuc...This study examined the role of PI3K/Akt pathway in radiosensitization of DNA damage of cervical carcinoma cells.The 50% inhibition concentration(IC50) of cisplatin and docetaxel in HeLa cells was detected by Mono-nuclear cell direct cytotoxicity assay(MTT) in vitro.HeLa cells were treated by cisplatin/docetaxel of 10 percent of IC20 alone or combined with LY294002 for 24 h,and then radiated by different doses of X-ray.The cell survival ratio was obtained by means of clone formation.One-hit multi-target model was fitted to the cell survival curve to calculate dose quasithreshold(Dq),mean lethal dose(D0),2Gy survival fraction(SF2) and sensitization enhancement ratio(SER).The pAkt and total Akt expression was detected by Western blotting and DNA damage by neutro-comet electrophoresis.The HeLa cells were randomly divided into 7 groups in terms of different treatments:Control;radiation treatment(RT) group;LY294002+RT group;cisplatin+RT group;docetaxel+RT group;LY294002+cisplatin+RT group;LY294002+docetaxel+RT group.The apoptosis ratio of each group was measured by flow cytometry.The results showed that docetaxel and cisplatin significantly enhanced the phosphorylation of Akt in radiation-treated HeLa cells.The Dq,D0 and SF2 in LY294002-contained groups were lower than those in docetaxel or cisplatin+RT group.The SER in the LY294002+docetaxel+RT group was 1.35 times that of the docetaxel+RT group,and that in the LY294002+cisplatin+RT group 1.26 times that of the cisplatin+RT group.The Comet electrophoresis showed that tail distance in the LY294002+cisplatin+RT group or LY294002+docetaxel+RT group was longer than in the cisplatin+RT group or docetaxel+RT group.The apoptosis ratio in the LY294002+cisplatin+RT group or LY294002+docetaxel +RT group was higher than in the cisplatin+RT group or docetaxel+RT group.It was concluded that inhibiting PI3K/Akt pathway can increase the effect of docetaxel and cisplatin on the radiosensitivity of HeLa cells and DNA damage resulted from radiation.展开更多
Objective:RECQL4(a member of the RECQ helicase family)upregulation has been reported to be associated with tumor progression in several malignancies.However,whether RECQL4 sustains esophageal squamous cell carcinoma(E...Objective:RECQL4(a member of the RECQ helicase family)upregulation has been reported to be associated with tumor progression in several malignancies.However,whether RECQL4 sustains esophageal squamous cell carcinoma(ESCC)has not been elucidated.In this study,we determined the functional role for RECQL4 in ESCC progression.Methods:RECQL4 expression in clinical samples of ESCC was examined by immunohistochemistry.Cell proliferation,cellular senescence,the epithelial-mesenchymal transition(EMT),DNA damage,and reactive oxygen species in ESCC cell lines with RECQL4 depletion or overexpression were analyzed.The levels of proteins involved in the DNA damage response(DDR),cell cycle progression,survival,and the EMT were determined by Western blot analyses.Results:RECQL4 was highly expressed in tumor tissues when compared to adjacent non-tumor tissues in ESCC(P<0.001)and positively correlated with poor differentiation(P=0.011),enhanced invasion(P=0.033),and metastasis(P=0.048).RECQL4 was positively associated with proliferation and migration in ESCC cells.Depletion of RECQL4 also inhibited growth of tumor xenografts in vivo.RECQL4 depletion induced G0/G1 phase arrest and cellular senescence.Importantly,the levels of DNA damage and reactive oxygen species were increased when RECQL4 was depleted.DDR,as measured by the activation of ATM,ATR,CHK1,and CHK2,was impaired.RECQL4 was also shown to promote the activation of AKT,ERK,and NF-k B in ESCC cells.Conclusions:The results indicated that RECQL4 was highly expressed in ESCC and played critical roles in the regulation of DDR,redox homeostasis,and cell survival.展开更多
Carbon ion radiotherapy has the advantages of better therapeutic effect and fewer side effects compared with those of X-rays in many kinds of tumors,including prostate cancer,and thus is an attractive treatment approa...Carbon ion radiotherapy has the advantages of better therapeutic effect and fewer side effects compared with those of X-rays in many kinds of tumors,including prostate cancer,and thus is an attractive treatment approach for prostate cancer.However,the biological effects and underlying mechanisms of carbon ion irradiation in prostate cancer are not yet fully understood.Therefore,this study systematically compared the effects of carbon ion irradiation with those of X-ray irradiation on DNA damage response and found that carbon ion irradiation was more effective than X-ray irradiation.Carbon ion irradiation can induce a high level of DNA double-strand break damage,reflected by the number of y-H2 A histone family member X foci,as well as by the foci lasting time and size.Moreover,carbon ion irradiation exhibited strong and long-lasting inhibitory effect on cell survival capability,induced prolonged cell cycle arrest,and increased apoptosis in PC-3 cells.As an underlying mechanism,we speculated that carbon ion irradiation-induced DNA damage evokes cell cycle arrest and apoptosis via the pRb/E2 F1/c-Myc signaling pathway to enhance the radiosensitivity of p53-deficient prostate cancer PC-3 cells.Collectively,the present study suggests that carbon ion irradiation is more efficient than X-ray irradiation and may help to understand the effects of different radiation qualities on the survival potential of p53-deficient prostate cancer cells.展开更多
BACKGROUND: Previous studies have suggested that the hippocampus is one of the neurotoxic target sites for lead. However, the molecular mechanisms of action, including the effect of lead on cell-cycle arrest, remain p...BACKGROUND: Previous studies have suggested that the hippocampus is one of the neurotoxic target sites for lead. However, the molecular mechanisms of action, including the effect of lead on cell-cycle arrest, remain poorly understood. OBJECTIVE: To investigate the effects of different lead concentrations on cell-cycle arrest, DNA damage, and cyclin D1 expression in primary cultured rat hippocampal neurons. DESIGN, TIME AND SETTING: A randomized, controlled, in vitro experiment was performed at the China Medical University between July 2008 and May 2009. MATERIALS: Antibodies specific to cyclin D1 and actin were synthesized and purified by Santa Cruz Biotechnology, USA. FACStar flow cytometer was purchased from Becton Dickinson, San Jose, California, USA. METHODS: Wistar rat hippocampal neurons were primary cultured for 7 days. Neurons in the control group were treated with 0.01 mol/L phosphate buffered saline. Neurons in the 0.2, 1.0, and 10 μmol/L lead acetate groups were subjected to 0.2, 1.0, and 10 μmol/L lead acetate. Subsequently, hippocampal neurons in each group were cultured for 24 hours. MAIN OUTCOME MEASURES: The effects of lead on cell cycle were measured by flow cytometry, DNA damage was measured using the comet assay, and cyclin D1 expression was measured using Western blot analysis. RESULTS: Treatment of hippocampal neurons with 0.2 μmol/L lead acetate did not significantly alter cell cycle phase distribution, i.e., sub-G1, S, G0/G1, G2/M, whereas treatment with 1.0 and 10 μmol/L lead acetate significantly increased the percentage of S and sub-G1 phase cells (P < 0.05). Olive tail moment in all lead-treated groups and the percentage of DNA in the tail in 1.0 μmol/L and 10 μmol/L lead acetate groups were significantly greater compared with the control group (P < 0.05). In addition, the percentage of tail DNA was greater in the 0.2 μmol/L lead acetate group compared with the control group (P > 0.05). Following incubation with 0.2, 1.0, and 10 μmol/L lead acetate for 24 hours, cyclin D1 expression gradually decreased with exposure to increasing lead acetate concentrations (1.0-10 μmol/L). CONCLUSION: Lead exposure to primary cultured rat hippocampal neurons resulted in dose-dependently disturbed cellular homeostasis, including DNA damage, reduced cyclin D1 expression, and stagnation of cell-cycle progression.展开更多
Objective:To explore the possible effects of naringin on acrylamide-induced nephrotoxicity in rats.Methods:Sprague-Dawley rats weighing 200-250 g were randomly divided into five groups.The control group was given intr...Objective:To explore the possible effects of naringin on acrylamide-induced nephrotoxicity in rats.Methods:Sprague-Dawley rats weighing 200-250 g were randomly divided into five groups.The control group was given intragastric(i.g.)saline(1 mL)for 10 d.The acrylamide group was given i.g.acrylamide in saline(38.27 mg/kg titrated to 1 mL)for 10 d.The treatment groups were administered with naringin in saline(50 and 100 mg/kg,respectively)for 10 d and given i.g.acrylamide(38.27 mg/kg)1 h after naringin injection.The naringin group was given i.g.naringin(100 mg/kg)alone for 10 d.On day 11,intracardiac blood samples were obtained from the rats when they were under anesthesia,after which they were euthanized.Urea and creatinine concentrations of blood serum samples were analyzed with an autoanalyzer.Enzyme-linked immunosorbent assay was used to quantify malondialdehyde,superoxide dismutase,glutathione,glutathione peroxidase,catalase,tumor necrosis factor-α,nuclear factor-κB,interleukin(IL)-33,IL-6,IL-1β,cyclooxygenase-2,kidney injury molecule-1,mitogen-activated protein kinase-1,and caspase-3 in kidney tissues.Renal tissues were also evaluated by histopathological and immunohistochemical examinations for 8-OHdG and Bcl-2.Results:Naringin attenuated acrylamide-induced nephrotoxicity by significantly decreasing serum urea and creatinine levels.Naringin increased superoxide dismutase,glutathione,glutathione peroxidase,and catalase activities and decreased malondialdehyde levels in kidney tissues.In addition,naringin reduced the levels of inflammatory and apoptotic parameters in kidney tissues.The histopathological assay showed that acrylamide caused histopathological changes and DNA damage,which were ameliorated by naringin.Conclusions:Naringin attenuated inflammation,apoptosis,oxidative stress,and oxidative DNA damage in acrylamide-induced nephrotoxicity in rats.展开更多
OBJECTIVE Reactive oxygen species(ROS)mediated both apoptosis and protective autophagy in response to natural products while the detailed mechanisms remain unclear.Cucurbitacin B(Cuc B),a natural tetracyclic triterpen...OBJECTIVE Reactive oxygen species(ROS)mediated both apoptosis and protective autophagy in response to natural products while the detailed mechanisms remain unclear.Cucurbitacin B(Cuc B),a natural tetracyclic triterpene,induced both protective autophagy and apoptosis mediated by ROS.This study was designed to explore the mechanism of Cuc B-induced apoptosis and autophagy in hepatocellular carcinoma BEL-7402cells.METHODS AND RESULTS Cuc B decreased cell viability in concentration-and time-dependent manners.Cuc B caused long comet tails and increased expression ofγHA2X,phosphorylation of ATM/ATR,and Chk1/Chk2.This DNA damage response was inhibited by KU55933 and caffeine.Cuc B induced autophagy as evidenced by monodansylcadaverine(MDC)staining,increased expression of LC3Ⅱ,phosphorylated ULK1and decreased expression of phosphorylated AKT,mT OR.Cuc B induced apoptosis mediated by Bcl-2 family proteins and caspase activation.Furthermore,Cuc B induced ROS formation,which was inhibited by N-acetylL-cysteine(NAC).NAC pretreatment dramatical y reversed Cuc B-induced DNA damage,autophagy,and apoptosis.Cuc B-induced apoptosis was reversed by NAC but enhanced by 3-methyladenine(3-MA),chloroquine(CQ),and silencing phosphatase and tensin homolog(PTEN).3-MA and CQ showed no effect on Cuc B-induced DNA damage.In addition,Cuc B increased PTEN phosphorylation.Silence PTEN restored Cuc B-induced autophagic protein expressions without affecting DNA damage.CONCLUSION Cuc B induced DNA damage,apoptosis and protective autophagy mediated by ROS.PTEN activation in response to DNA damage bridged apoptosis and pro-survival autophagy.These observations provide insights for better understanding the crosstalk between apoptosis and autophagy.展开更多
Objective:DNA damage response(DDR)genes have low mutation rates,which may restrict their clinical applications in predicting the outcomes of immune checkpoint inhibitor(ICI)treatment.Thus,a systemic analysis of multip...Objective:DNA damage response(DDR)genes have low mutation rates,which may restrict their clinical applications in predicting the outcomes of immune checkpoint inhibitor(ICI)treatment.Thus,a systemic analysis of multiple DDR genes is needed to identify potential biomarkers of ICI efficacy.Methods:A total of 39,631 patients with mutation data were selected from the cBioPortal database.A total of 155 patients with mutation data were obtained from the Fudan University Shanghai Cancer Center(FUSCC).A total of 1,660 patients from the MSK-IMPACT cohort who underwent ICI treatment were selected for survival analysis.A total of 249 patients who underwent ICI treatment from the Dana-Farber Cancer Institute(DFCI)cohort were obtained from a published dataset.The Cancer Genome Atlas(TCGA)level 3 RNA-Seq version 2 RSEM data for gastric cancer were downloaded from cBioPortal.Results:Six MMR and 30 DDR genes were included in this study.Six MMR and 20 DDR gene mutations were found to predict the therapeutic efficacy of ICI,and most of them predicted the therapeutic efficacy of ICI,in a manner dependent on TMB,except for 4 combined DDR gene mutations,which were associated with the therapeutic efficacy of ICI independently of the TMB.Single MMR/DDR genes showed low mutation rates;however,the mutation rate of all the MMR/DDR genes associated with the therapeutic efficacy of ICI was relatively high,reaching 10%–30%in several cancer types.Conclusions:Coanalysis of multiple MMR/DDR mutations aids in selecting patients who are potential candidates for immunotherapy.展开更多
Objective:Mitotic arrest-deficient protein 1(MAD1)is a kinetochore protein essential for the mitotic spindle checkpoint.Proteomic studies have indicated that MAD1 is a component of the DNA damage response(DDR)pathway....Objective:Mitotic arrest-deficient protein 1(MAD1)is a kinetochore protein essential for the mitotic spindle checkpoint.Proteomic studies have indicated that MAD1 is a component of the DNA damage response(DDR)pathway.However,whether and how MAD1 might be directly involved in the DDR is largely unknown.Methods:We ectopically expressed the wild type,or a phosphorylation-site--mutated form of MAD1 in MAD1 knockdown cells to look for complementation effects.We used the comet assay,colony formation assay,immunofluorescence staining,and flow cytometry to assess the DDR,radiosensitivity,and the G2/M checkpoint.We employed co-immunoprecipitation followed by mass spectrometry to identify MAD1 interacting proteins.Data were analyzed using the unpaired Student'st-test.Results:We showed that MAD1 was required for an optimal DDR,as knocking down MAD1 resulted in impaired DNA repair and hypersensitivity to ionizing radiation(IR).We found that IR-induced serine 214 phosphorylation was ataxia-telangiectasia mutated(ATM)kinase-dependent.Mutation of serine 214 to alanine failed to rescue the phenotypes of MAD1 knockdown cells in response to IR.Using mass spectrometry,we identified a protein complex mediated by MAD1 serine 214 phosphorylation in response to IR.Among them,we showed that KU80 was a key protein that displayed enhanced interaction with MAD1 after DNA damage.Finally,we showed that MAD1 interaction with KU80 required serine 214 phosphorylation,and it was essential for activation of DNA protein kinases catalytic subunit(DNA-PKcs).Conclusions:MAD1 serine 214 phosphorylation mediated by ATM kinase in response to IR was required for the interaction with KU80 and activation of DNA-PKCs.展开更多
The activation of some oncogenes promote cancer cell proliferation and growth,facilitate cancer progression and metastasis by induce DNA replication stress,even genome instability.Activation of the cyclic GMP-AMP synt...The activation of some oncogenes promote cancer cell proliferation and growth,facilitate cancer progression and metastasis by induce DNA replication stress,even genome instability.Activation of the cyclic GMP-AMP synthase(cGAS)mediates classical DNA sensing,is involved in genome instability,and is linked to various tumor development or therapy.However,the function of cGAS in gastric cancer remains elusive.In this study,the TCGA database and retrospective immunohistochemical analyses revealed substantially high cGAS expression in gastric cancer tissues and cell lines.By employing cGAS high-expression gastric cancer cell lines,including AGS and MKN45,ectopic silencing of cGAS caused a significant reduction in the proliferation of the cells,tumor growth,and mass in xenograft mice.Mechanistically,database analysis predicted a possible involvement of cGAS in the DNA damage response(DDR),further data through cells revealed protein interactions of the cGAS and MRE11-RAD50-NBN(MRN)complex,which activated cell cycle checkpoints,even increased genome instability in gastric cancer cells,thereby contributing to gastric cancer progression and sensitivity to treatment with DNA damaging agents.Furthermore,the upregulation of cGAS significantly exacerbated the prognosis of gastric cancer patients while improving radiotherapeutic outcomes.Therefore,we concluded that cGAS is involved in gastric cancer progression by fueling genome instability,implying that intervening in the cGAS pathway could be a practicable therapeutic approach for gastric cancer.展开更多
Background:Replication stress response is crucial for the maintenance of a stable ge-nome.POLDIP3(DNA polymerase delta interacting protein 3)was initially identified as one of the DNA polymeraseδ(Polδ)interacting pr...Background:Replication stress response is crucial for the maintenance of a stable ge-nome.POLDIP3(DNA polymerase delta interacting protein 3)was initially identified as one of the DNA polymeraseδ(Polδ)interacting proteins almost 20 years ago.Using a variety of in vitro biochemical assays,we previously established that POLDIP3 is a key regulator of the enzymatic activity of Polδ.However,the in vivo function of POLDIP3 in DNA replication and DNA damage response has been elusive.Methods:We first generated POLDIP3 knockout(KO)cells using the CRISPR/Cas9 technology.We then investigated its biological functions in vivo using a variety of biochemical and cell biology assays.Results:We showed that although the POLDIP3-KO cells manifest no pronounced defect in global DNA synthesis under nonstress conditions,they are sensitive to a va-riety of replication fork blockers.Intriguingly,we found that POLDIP3 plays a crucial role in the activation and maintenance of the DNA damage checkpoint in response to exogenous as well as endogenous replication stress.Conclusion:Our results indicate that when the DNA replication fork is blocked,POLDIP3 can be recruited to the stalled replication fork and functions to bridge the early DNA damage checkpoint response and the later replication fork repair/restart.展开更多
Esophageal cancer(EC)was an aggressive malignant neoplasm characterized by high morbidity and poor prognosis.Identifying the changes in DNA damage repair genes helps to better understand the mechanisms of carcinoma pr...Esophageal cancer(EC)was an aggressive malignant neoplasm characterized by high morbidity and poor prognosis.Identifying the changes in DNA damage repair genes helps to better understand the mechanisms of carcinoma progression.In this study,by comparing EC samples and normal samples,we found a total of 132 DDR expression with a significant difference.Moreover,we revealed higher expression of POLN,PALB2,ATM,PER1,TOP3B and lower expression of HMGB1,UBE2B were correlated to longer OS in EC.In addition,a prognostic risk score based on 7 DDR gene expression(POLN,HMGB1,TOP3B,PER1,UBE2B,ATM,PALB2)was constructed for the prognosis of EC.Meanwhile,EC cancer samples were divided into 3 subtypes based on 132 DDR genes expressions.Clinical profile analysis showed cluster C1 and C2 showed a similar frequency of T2,which was remarked higher than that in cluster 3.Moreover,we found the immune cell inflation levels were significantly changed in different subtypes of EC.The infiltration levels of T cell CD8+,B cell and NK cells were greatly higher in cluster 2 than that in cluster 1 and cluster 3.The results showed T cell CD4+infiltration levels were dramatically higher in cluster 1 than that in cluster 2 and cluster 3.Finally,we perform bioinformatics analysis of DEGs among 3 subtypes of EC and found DDR genes may be related to multiple signaling,such as Base excision repair,Cell cycle,Hedgehog signaling pathway,and Glycolysis/Gluconeogenesis.These results showed DDR genes may serve as new target for the prognosis of EC and prediction of the potential response of immune therapy in EC.展开更多
Acrylamide(AA)is ubiquitous in packaging materials,paints,cosmetics,food and drinking water.However,AA has obvious neurotoxicity,reproductive toxicity and carcinogenicity,which seriously endangers human health.As one ...Acrylamide(AA)is ubiquitous in packaging materials,paints,cosmetics,food and drinking water.However,AA has obvious neurotoxicity,reproductive toxicity and carcinogenicity,which seriously endangers human health.As one of precious traditional Chinese medicines,Gastrodia elata Bl.has been mainly used to lower blood pressure and resist myocardial ischemia.However,the antioxidant activity of Gastrodia elata Bl.on AA-induced DNA damage has not been reported.We found that AA(25,30 and 50 mg/kg)could cause DNA damage and the damage was time/dose dependent.After AA administration,Tail moment,micronuclei formation rate,8-OHdG and MDA level were significantly increased and SOD activity was decreased.Gastrodia elata Bl.decoction,gastrodin and vitamin C could reduce AA-induced DNA damage by decreasing AA-induced increment of tail moment and micronuclei formation rate.What’s more,Gastrodia elata Bl.decoction,gastrodin and vitamin C could lower 8-OHdG and MDA level and improve SOD activity.In conclusion,our research showed that Gastrodia elata Bl.decoction and gastrodin had protective effects on AA-induced DNA damage,and the potential protective mechanism might be related to anti-oxidative stress.展开更多
Diagnosis and biological behavior of breast cancer of female dog represent one of the biggest challenges facing the Veterinarian in recent years. Due to its exponential growth and the degree of aggressiveness, the exa...Diagnosis and biological behavior of breast cancer of female dog represent one of the biggest challenges facing the Veterinarian in recent years. Due to its exponential growth and the degree of aggressiveness, the exact cause of this tumor is probably multifactorial and it is believed that may suffer influence from environmental factors. Among the suspected environmental contaminants are the pyrethroids. Aiming to investigate the participation of pyrethroids in tumorigenesis in female dogs, a study was conducted using 50 female dogs, 22 were positive for simple breast carcinoma (Group I), 18 with a diagnosis of complex breast carcinoma (Group II) and 10 negative (Group III) for breast cancer. In order to detect DNA damage, the Comet assay was performed on mammary samples of these animals, which also had samples submitted to the technique of High Performance Liquid Chromatography (HPLC), which aimed to quantify the concentration of pyrethroids. The results of HPLC of each animal were compared with those obtained by the Comet assay analysis of variance and the means were compared by the test groups “Student T” at the significance level of p ￡ 0.05. Despite presenting correlation between the amount of DNA damage and tumor aggressiveness, no statistical differences were found in the DNA damage of different histologic types of breast carcinoma. As for pyrethroids, even these were detected in 22% of tumor tissues and peritumoral fat, there was no difference in DNA damage between cells exposed and not exposed to environmental contaminant.展开更多
Oxidative stress has been implicated in the inflammatory process of Systemic Lupus Erythematosus (SLE), particularly by the formation of anti-DNA autoantibodies, which can lead to DNA damage. The aim of this study was...Oxidative stress has been implicated in the inflammatory process of Systemic Lupus Erythematosus (SLE), particularly by the formation of anti-DNA autoantibodies, which can lead to DNA damage. The aim of this study was to investigate, through comet assay, whether the level of DNA damage in SLE patients is different from that of healthy subjects. Twenty-five adult SLE patients with SLEDAI up to ten, and 25 healthy subjects were paired according to age, gender and Body Mass Index (BMI). Other anthropometric variables were also assessed. Comet assay was assessed as the marker of oxidative stress described as DNA Damage (DD) percentage. Waist Circumference (WC), Hip Circumference (HC) and BMI were also performed. Exclusion criteria for patients and controls comprised smoking and other chronic disorders. Level of damage index was remarkably higher in SLE patients than in controls, and no significant differences between the groups were found for age, BMI, WC and HC. No stratification concerning gender was performed, since there were just two males per group. No correlation was observed between BMI and DD (%). DD increased in SLE, which reflects the oxidant/antioxidant imbalance in these patients. These findings support an association between oxidative stress and SLE. This stronger correlation observed in patients with low disease activity may be useful in elucidating the mechanisms of disease pathogenesis.展开更多
Aluminum(Al)can lead to an exposure of creature in varieties ways for its universality,and it could disturb normal physiological metabolism,with the damage to multisystem including reproduction.Since the oocyte qualit...Aluminum(Al)can lead to an exposure of creature in varieties ways for its universality,and it could disturb normal physiological metabolism,with the damage to multisystem including reproduction.Since the oocyte quality is critical for female reproduction,we inspected the toxicity of Al on mouse oocyte maturation.We constructed in vitro exposure mouse model,and we found that 5 mmol/L Al had adverse effects on oocyte maturation by impairing organelle and cytoskeleton.Aberrant spindle and misaligned chromosomes which might be considered to be caused by elevated levels of acetylation,as well as abnormal distribution of actin dynamics could hinder normal meiosis of oocytes.Organelle dysfunction indicated that Al affected proteins synthesis,transport and digestion,which would further damage oocyte maturation.In order to explore the mechanism of Al toxicity,our further investigation demonstrated that Al caused mitochondrial dysfunction and imbalance calcium homeostasis,resulting in limited energy supply.Moreover,high level of reactive oxygen species,DNA damage and apoptosis caused by oxidative stress were also the manifestation of Al toxicity on oocytes.In conclusion,our study provided the evidence that Al exposure affected oocyte quality through its effects on spindle organization,actin dynamics,organelle function and the induction of DNA damage-related apoptosis with mouse model.展开更多
Cancer,a complex and heterogeneous disease,arises from genomic instability.Currently,DNA damage-based cancer treatments,including radiotherapy and chemotherapy,are employed in clinical practice.However,the efficacy an...Cancer,a complex and heterogeneous disease,arises from genomic instability.Currently,DNA damage-based cancer treatments,including radiotherapy and chemotherapy,are employed in clinical practice.However,the efficacy and safety of these therapies are constrained by various factors,limiting their ability to meet current clinical demands.Metal nanoparticles present promising avenues for enhancing each critical aspect of DNA damage-based cancer therapy.Their customizable physicochemical properties enable the development of targeted and personalized treatment platforms.In this review,we delve into the design principles and optimization strategies of metal nanoparticles.We shed light on the limitations of DNA damage-based therapy while highlighting the diverse strategies made possible by metal nanoparticles.These encompass targeted drug delivery,inhibition of DNA repair mechanisms,induction of cell death,and the cascading immune response.Moreover,we explore the pivotal role of physicochemical factors such as nanoparticle size,stimuli-responsiveness,and surface modification in shaping metal nanoparticle platforms.Finally,we present insights into the challenges and future directions of metal nanoparticles in advancing DNA damage-based cancer therapy,paving the way for novel treatment paradigms.展开更多
Clinical application of doxorubicin(DOX)is heavily hindered by DOX cardiotoxicity.Several theories were postulated for DOX cardiotoxicity including DNA damage and DNA damage response(DDR),although the mechanism(s)invo...Clinical application of doxorubicin(DOX)is heavily hindered by DOX cardiotoxicity.Several theories were postulated for DOX cardiotoxicity including DNA damage and DNA damage response(DDR),although the mechanism(s)involved remains to be elucidated.This study evaluated the potential role of TBC domain family member 15(TBC1D15)in DOX cardiotoxicity.Tamoxifen-induced cardiac-specific Tbcldi5 knockout(Tbcldi5^(CKO))or Tbcldi5 knockin(Tbcldi5^(CKI))male mice were challenged with a single dose of DOx prior to cardiac assessment 1 week or 4 weeks following DOX challenge.Adenoviruses encoding TBC1D15 or containing shRNA targeting Tbcld15 were used for Tbcld15 overexpression or knockdown in isolated primary mouse cardiomyocytes.Our results re-vealed that DOX evoked upregulation of TBC1D15 with compromised myocardial function and overt mortality,the effects of which were ameliorated and accentuated by Tbcldi5 deletion and Tbcld15 overexpression,respectively.DOX overtly evoked apoptotic cell death,the effect of which was alleviated and exacerbated by Tbcld15 knockout and overexpression,respectively.Meanwhile,DOX provoked mitochondrial membrane potential collapse,oxidative stress and DNA damage,the effects of which were mitigated and exacerbated by Tbcld15 knockdown and overexpression,respectively.Further scrutiny revealed that TBC1D15 fostered cytosolic accumulation of the cardinal DDR element DNA-dependent protein kinase catalytic subunit(DNA-PKcs).Liquid chromatography-tandem mass spectrometry and coimmunoprecipitation denoted an interaction between TBCID15 and DNA-PKcs at the segment 594-624 of TBC1D15.Moreover,overexpression of TBC1D15 mutant(A594-624,deletion of segment 594-624)failed to elicit accentuation of DOX-induced cytosolic retention of DNA-PKcs,DNA damage and cardiomyocyte apoptosis by TBC1D15 wild type.However,Tbcld15 deletion ameliorated DOXinduced cardiomyocyte contractile anomalies,apoptosis,mitochondrial anomalies,DNA damage and cytosolic DNA-PKcs accumulation,which were canceled off by DNA-PKcs inhibition or ATM activation.Taken together,our findings denoted a pivotal role for TBCID15 in DOX-induced DNA damage,mitochondrial injury,and apoptosis possibly through binding with DNA-PKcs and thus gate-keeping its cytosolic retention,a route to accentuation of cardiac contractile dysfunction in DOX-induced cardiotoxicity.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 81972761 and 82202837)the National Key R&D Program of China (Grant Nos. 2016YFC1303200 and 2022YFC2505100)。
文摘Objective: DNA damage response(DDR) deficiency has emerged as a prominent determinant of tumor immunogenicity. This study aimed to construct a DDR-related immune activation(DRIA) signature and evaluate the predictive accuracy of the DRIA signature for response to immune checkpoint inhibitor(ICI) therapy in gastrointestinal(GI) cancer.Methods: A DRIA signature was established based on two previously reported DNA damage immune response assays. Clinical and gene expression data from two published GI cancer cohorts were used to assess and validate the association between the DRIA score and response to ICI therapy. The predictive accuracy of the DRIA score was validated based on one ICI-treated melanoma and three pan-cancer published cohorts.Results: The DRIA signature includes three genes(CXCL10, IDO1, and IFI44L). In the discovery cancer cohort, DRIA-high patients with gastric cancer achieved a higher response rate to ICI therapy than DRIA-low patients(81.8% vs. 8.8%;P < 0.001), and the predictive accuracy of the DRIA score [area under the receiver operating characteristic curve(AUC) = 0.845] was superior to the predictive accuracy of PD-L1 expression, tumor mutational burden, microsatellite instability, and Epstein–Barr virus status. The validation cohort demonstrated that the DRIA score identified responders with microsatellite-stable colorectal and pancreatic adenocarcinoma who received dual PD-1 and CTLA-4 blockade with radiation therapy. Furthermore, the predictive performance of the DRIA score was shown to be robust through an extended validation in melanoma, urothelial cancer, and pan-cancer.Conclusions: The DRIA signature has superior and robust predictive accuracy for the efficacy of ICI therapy in GI cancer and pancancer, indicating that the DRIA signature may serve as a powerful biomarker for guiding ICI therapy decisions.
基金supported by grants from the National Key Research and Development Program of China(2017YFB0403802)the Outstanding Youth Project of the Natural Science Foundation of Heilongjiang Province(YQ2020H019)the Huaier Fund in 2023 from Chen Xiao-Ping Foundation for the Development of Science and Technology of Hubei Province.
文摘Background:Phototherapies based on sunlight,infrared,ultraviolet,visible,and laser-based treatments present advantages like high curative effects,small invasion,and negligible adverse reactions in cancer treatment.We aimed to explore the potential therapeutic effects of blue light emitting diode(LED)in human hepatoma cells and decipher the underlying cellular and molecular mechanisms.Methods:Wound healing and transwell assays were employed to probe the inhibition of the invasion and migration of hepatocellular carcinoma cells in the presence of blue LED.The sphere-forming test was used to evaluate the effect of LED blue light irradiation on cancer stem cell properties.Immunofluorescence and western blotting were used to detect the changes inγ-H2AX.The Cell Counting Kit-8 assay,5-ethynyl-2′-deoxyuridine staining,and colony formation assay were used to detect the combined effect of blue LED and sorafenib on cell proliferation inhibition.Results:We demonstrated that the irradiation of blue LED light in hepatoma cells could lead to cell proliferation reduction along with the increase of cell apoptosis.Simultaneously,blue LED irradiation also markedly suppressed the migration and invasion ability of human hepatoma cells.Sphere formation analysis further revealed the decreased cancer stemness of hepatoma cells upon blue LED irradiation.Mechanistically,blue LED irradiation significantly promoted the expression of the phosphorylation of the core histone protein H2AX(γ-H2AX),a sensitive molecular marker of DNA damage.In addition,we found that the combined treatment of blue LED irradiation and sorafenib increased cancer cell sensitivity to sorafenib.Conclusion:Collectively,we demonstrated that blue LED irradiation exhibited anti-tumor effects on liver cancer cells by inducing DNA damage and could enhance chemosensitivity of cancer cells,which represents a potential approach for human hepatoma treatment.
基金supported by grants from the Hubei Province Natural Sciences Foundation (No.2008cdb133)Science Foundation for The Youth Scholars of Ministry of Education of China (No.200804871034)
文摘This study examined the role of PI3K/Akt pathway in radiosensitization of DNA damage of cervical carcinoma cells.The 50% inhibition concentration(IC50) of cisplatin and docetaxel in HeLa cells was detected by Mono-nuclear cell direct cytotoxicity assay(MTT) in vitro.HeLa cells were treated by cisplatin/docetaxel of 10 percent of IC20 alone or combined with LY294002 for 24 h,and then radiated by different doses of X-ray.The cell survival ratio was obtained by means of clone formation.One-hit multi-target model was fitted to the cell survival curve to calculate dose quasithreshold(Dq),mean lethal dose(D0),2Gy survival fraction(SF2) and sensitization enhancement ratio(SER).The pAkt and total Akt expression was detected by Western blotting and DNA damage by neutro-comet electrophoresis.The HeLa cells were randomly divided into 7 groups in terms of different treatments:Control;radiation treatment(RT) group;LY294002+RT group;cisplatin+RT group;docetaxel+RT group;LY294002+cisplatin+RT group;LY294002+docetaxel+RT group.The apoptosis ratio of each group was measured by flow cytometry.The results showed that docetaxel and cisplatin significantly enhanced the phosphorylation of Akt in radiation-treated HeLa cells.The Dq,D0 and SF2 in LY294002-contained groups were lower than those in docetaxel or cisplatin+RT group.The SER in the LY294002+docetaxel+RT group was 1.35 times that of the docetaxel+RT group,and that in the LY294002+cisplatin+RT group 1.26 times that of the cisplatin+RT group.The Comet electrophoresis showed that tail distance in the LY294002+cisplatin+RT group or LY294002+docetaxel+RT group was longer than in the cisplatin+RT group or docetaxel+RT group.The apoptosis ratio in the LY294002+cisplatin+RT group or LY294002+docetaxel +RT group was higher than in the cisplatin+RT group or docetaxel+RT group.It was concluded that inhibiting PI3K/Akt pathway can increase the effect of docetaxel and cisplatin on the radiosensitivity of HeLa cells and DNA damage resulted from radiation.
基金supported by National Natural Science Foundation of China(Grant Nos.81572785,31771260,and 81201750)a Ministry of Science and Technology(Grant No.2011CB966200)+2 种基金the Excellent Young and Mid-Career Scientist Award of Shandong Province(Grant No.BS2013YY023)the Key Research Project of Shandong Province(Grant No.2016GSF201072)the Project of State Key Laboratory of Radiation Medicine and Protection,Soochow University(Grant No.GZN1201804)。
文摘Objective:RECQL4(a member of the RECQ helicase family)upregulation has been reported to be associated with tumor progression in several malignancies.However,whether RECQL4 sustains esophageal squamous cell carcinoma(ESCC)has not been elucidated.In this study,we determined the functional role for RECQL4 in ESCC progression.Methods:RECQL4 expression in clinical samples of ESCC was examined by immunohistochemistry.Cell proliferation,cellular senescence,the epithelial-mesenchymal transition(EMT),DNA damage,and reactive oxygen species in ESCC cell lines with RECQL4 depletion or overexpression were analyzed.The levels of proteins involved in the DNA damage response(DDR),cell cycle progression,survival,and the EMT were determined by Western blot analyses.Results:RECQL4 was highly expressed in tumor tissues when compared to adjacent non-tumor tissues in ESCC(P<0.001)and positively correlated with poor differentiation(P=0.011),enhanced invasion(P=0.033),and metastasis(P=0.048).RECQL4 was positively associated with proliferation and migration in ESCC cells.Depletion of RECQL4 also inhibited growth of tumor xenografts in vivo.RECQL4 depletion induced G0/G1 phase arrest and cellular senescence.Importantly,the levels of DNA damage and reactive oxygen species were increased when RECQL4 was depleted.DDR,as measured by the activation of ATM,ATR,CHK1,and CHK2,was impaired.RECQL4 was also shown to promote the activation of AKT,ERK,and NF-k B in ESCC cells.Conclusions:The results indicated that RECQL4 was highly expressed in ESCC and played critical roles in the regulation of DDR,redox homeostasis,and cell survival.
基金supported by the National Key R&D Program of China(No.2018YFE0205100)the Key Program of the National Natural Science Foundation of China(No.U1632270)+1 种基金National Natural Science Foundation of China(No.11665003)Cancer Research Youth Science Foundation of Chinese Anti-cancer Association(No.CAYC18A06)。
文摘Carbon ion radiotherapy has the advantages of better therapeutic effect and fewer side effects compared with those of X-rays in many kinds of tumors,including prostate cancer,and thus is an attractive treatment approach for prostate cancer.However,the biological effects and underlying mechanisms of carbon ion irradiation in prostate cancer are not yet fully understood.Therefore,this study systematically compared the effects of carbon ion irradiation with those of X-ray irradiation on DNA damage response and found that carbon ion irradiation was more effective than X-ray irradiation.Carbon ion irradiation can induce a high level of DNA double-strand break damage,reflected by the number of y-H2 A histone family member X foci,as well as by the foci lasting time and size.Moreover,carbon ion irradiation exhibited strong and long-lasting inhibitory effect on cell survival capability,induced prolonged cell cycle arrest,and increased apoptosis in PC-3 cells.As an underlying mechanism,we speculated that carbon ion irradiation-induced DNA damage evokes cell cycle arrest and apoptosis via the pRb/E2 F1/c-Myc signaling pathway to enhance the radiosensitivity of p53-deficient prostate cancer PC-3 cells.Collectively,the present study suggests that carbon ion irradiation is more efficient than X-ray irradiation and may help to understand the effects of different radiation qualities on the survival potential of p53-deficient prostate cancer cells.
基金the National Natural Science Foundation of China, No. 39970651
文摘BACKGROUND: Previous studies have suggested that the hippocampus is one of the neurotoxic target sites for lead. However, the molecular mechanisms of action, including the effect of lead on cell-cycle arrest, remain poorly understood. OBJECTIVE: To investigate the effects of different lead concentrations on cell-cycle arrest, DNA damage, and cyclin D1 expression in primary cultured rat hippocampal neurons. DESIGN, TIME AND SETTING: A randomized, controlled, in vitro experiment was performed at the China Medical University between July 2008 and May 2009. MATERIALS: Antibodies specific to cyclin D1 and actin were synthesized and purified by Santa Cruz Biotechnology, USA. FACStar flow cytometer was purchased from Becton Dickinson, San Jose, California, USA. METHODS: Wistar rat hippocampal neurons were primary cultured for 7 days. Neurons in the control group were treated with 0.01 mol/L phosphate buffered saline. Neurons in the 0.2, 1.0, and 10 μmol/L lead acetate groups were subjected to 0.2, 1.0, and 10 μmol/L lead acetate. Subsequently, hippocampal neurons in each group were cultured for 24 hours. MAIN OUTCOME MEASURES: The effects of lead on cell cycle were measured by flow cytometry, DNA damage was measured using the comet assay, and cyclin D1 expression was measured using Western blot analysis. RESULTS: Treatment of hippocampal neurons with 0.2 μmol/L lead acetate did not significantly alter cell cycle phase distribution, i.e., sub-G1, S, G0/G1, G2/M, whereas treatment with 1.0 and 10 μmol/L lead acetate significantly increased the percentage of S and sub-G1 phase cells (P < 0.05). Olive tail moment in all lead-treated groups and the percentage of DNA in the tail in 1.0 μmol/L and 10 μmol/L lead acetate groups were significantly greater compared with the control group (P < 0.05). In addition, the percentage of tail DNA was greater in the 0.2 μmol/L lead acetate group compared with the control group (P > 0.05). Following incubation with 0.2, 1.0, and 10 μmol/L lead acetate for 24 hours, cyclin D1 expression gradually decreased with exposure to increasing lead acetate concentrations (1.0-10 μmol/L). CONCLUSION: Lead exposure to primary cultured rat hippocampal neurons resulted in dose-dependently disturbed cellular homeostasis, including DNA damage, reduced cyclin D1 expression, and stagnation of cell-cycle progression.
文摘Objective:To explore the possible effects of naringin on acrylamide-induced nephrotoxicity in rats.Methods:Sprague-Dawley rats weighing 200-250 g were randomly divided into five groups.The control group was given intragastric(i.g.)saline(1 mL)for 10 d.The acrylamide group was given i.g.acrylamide in saline(38.27 mg/kg titrated to 1 mL)for 10 d.The treatment groups were administered with naringin in saline(50 and 100 mg/kg,respectively)for 10 d and given i.g.acrylamide(38.27 mg/kg)1 h after naringin injection.The naringin group was given i.g.naringin(100 mg/kg)alone for 10 d.On day 11,intracardiac blood samples were obtained from the rats when they were under anesthesia,after which they were euthanized.Urea and creatinine concentrations of blood serum samples were analyzed with an autoanalyzer.Enzyme-linked immunosorbent assay was used to quantify malondialdehyde,superoxide dismutase,glutathione,glutathione peroxidase,catalase,tumor necrosis factor-α,nuclear factor-κB,interleukin(IL)-33,IL-6,IL-1β,cyclooxygenase-2,kidney injury molecule-1,mitogen-activated protein kinase-1,and caspase-3 in kidney tissues.Renal tissues were also evaluated by histopathological and immunohistochemical examinations for 8-OHdG and Bcl-2.Results:Naringin attenuated acrylamide-induced nephrotoxicity by significantly decreasing serum urea and creatinine levels.Naringin increased superoxide dismutase,glutathione,glutathione peroxidase,and catalase activities and decreased malondialdehyde levels in kidney tissues.In addition,naringin reduced the levels of inflammatory and apoptotic parameters in kidney tissues.The histopathological assay showed that acrylamide caused histopathological changes and DNA damage,which were ameliorated by naringin.Conclusions:Naringin attenuated inflammation,apoptosis,oxidative stress,and oxidative DNA damage in acrylamide-induced nephrotoxicity in rats.
基金supported by the National Natural Science Foundation of China(No.41406088)The open fund of Key Laboratory for Ecological Environment in Coastal Areas,State Oceanic Administration(201506)
基金The project supported by Science and Technology Development Fund,Macao S.A.R(FDCT)(039/2014/A1)the Research Fund of University of Macao(MYRG2016-00043-ICMS-QRCM)
文摘OBJECTIVE Reactive oxygen species(ROS)mediated both apoptosis and protective autophagy in response to natural products while the detailed mechanisms remain unclear.Cucurbitacin B(Cuc B),a natural tetracyclic triterpene,induced both protective autophagy and apoptosis mediated by ROS.This study was designed to explore the mechanism of Cuc B-induced apoptosis and autophagy in hepatocellular carcinoma BEL-7402cells.METHODS AND RESULTS Cuc B decreased cell viability in concentration-and time-dependent manners.Cuc B caused long comet tails and increased expression ofγHA2X,phosphorylation of ATM/ATR,and Chk1/Chk2.This DNA damage response was inhibited by KU55933 and caffeine.Cuc B induced autophagy as evidenced by monodansylcadaverine(MDC)staining,increased expression of LC3Ⅱ,phosphorylated ULK1and decreased expression of phosphorylated AKT,mT OR.Cuc B induced apoptosis mediated by Bcl-2 family proteins and caspase activation.Furthermore,Cuc B induced ROS formation,which was inhibited by N-acetylL-cysteine(NAC).NAC pretreatment dramatical y reversed Cuc B-induced DNA damage,autophagy,and apoptosis.Cuc B-induced apoptosis was reversed by NAC but enhanced by 3-methyladenine(3-MA),chloroquine(CQ),and silencing phosphatase and tensin homolog(PTEN).3-MA and CQ showed no effect on Cuc B-induced DNA damage.In addition,Cuc B increased PTEN phosphorylation.Silence PTEN restored Cuc B-induced autophagic protein expressions without affecting DNA damage.CONCLUSION Cuc B induced DNA damage,apoptosis and protective autophagy mediated by ROS.PTEN activation in response to DNA damage bridged apoptosis and pro-survival autophagy.These observations provide insights for better understanding the crosstalk between apoptosis and autophagy.
基金This work was supported by the National Key R&D Program of China(Grant No.2018YFC1313300)the National Natural Science Foundation of China(Grant No.81572331).
文摘Objective:DNA damage response(DDR)genes have low mutation rates,which may restrict their clinical applications in predicting the outcomes of immune checkpoint inhibitor(ICI)treatment.Thus,a systemic analysis of multiple DDR genes is needed to identify potential biomarkers of ICI efficacy.Methods:A total of 39,631 patients with mutation data were selected from the cBioPortal database.A total of 155 patients with mutation data were obtained from the Fudan University Shanghai Cancer Center(FUSCC).A total of 1,660 patients from the MSK-IMPACT cohort who underwent ICI treatment were selected for survival analysis.A total of 249 patients who underwent ICI treatment from the Dana-Farber Cancer Institute(DFCI)cohort were obtained from a published dataset.The Cancer Genome Atlas(TCGA)level 3 RNA-Seq version 2 RSEM data for gastric cancer were downloaded from cBioPortal.Results:Six MMR and 30 DDR genes were included in this study.Six MMR and 20 DDR gene mutations were found to predict the therapeutic efficacy of ICI,and most of them predicted the therapeutic efficacy of ICI,in a manner dependent on TMB,except for 4 combined DDR gene mutations,which were associated with the therapeutic efficacy of ICI independently of the TMB.Single MMR/DDR genes showed low mutation rates;however,the mutation rate of all the MMR/DDR genes associated with the therapeutic efficacy of ICI was relatively high,reaching 10%–30%in several cancer types.Conclusions:Coanalysis of multiple MMR/DDR mutations aids in selecting patients who are potential candidates for immunotherapy.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.81672743 and 81974464)Beijing Tianjin Hebei Basic Research Cooperation Project(Grant No.19JCZDJC64500(Z))+4 种基金Shenzhen Basic Research Project(Grant No.JCYJ20160331114230843)Tianjin Municipal Health Commission(Grant Nos.2015KR11 and 2013KG134)Tianjin Municipal Science and Technology Bureau(Grant No.18JCYBJC27800)US NIH grant RO 1 CAI33093,the Alabama Innovation Fund of the United Statesthe Tianjin Medical University Cancer Institute and Hospital Innovation Fund(Grant No.1803)。
文摘Objective:Mitotic arrest-deficient protein 1(MAD1)is a kinetochore protein essential for the mitotic spindle checkpoint.Proteomic studies have indicated that MAD1 is a component of the DNA damage response(DDR)pathway.However,whether and how MAD1 might be directly involved in the DDR is largely unknown.Methods:We ectopically expressed the wild type,or a phosphorylation-site--mutated form of MAD1 in MAD1 knockdown cells to look for complementation effects.We used the comet assay,colony formation assay,immunofluorescence staining,and flow cytometry to assess the DDR,radiosensitivity,and the G2/M checkpoint.We employed co-immunoprecipitation followed by mass spectrometry to identify MAD1 interacting proteins.Data were analyzed using the unpaired Student'st-test.Results:We showed that MAD1 was required for an optimal DDR,as knocking down MAD1 resulted in impaired DNA repair and hypersensitivity to ionizing radiation(IR).We found that IR-induced serine 214 phosphorylation was ataxia-telangiectasia mutated(ATM)kinase-dependent.Mutation of serine 214 to alanine failed to rescue the phenotypes of MAD1 knockdown cells in response to IR.Using mass spectrometry,we identified a protein complex mediated by MAD1 serine 214 phosphorylation in response to IR.Among them,we showed that KU80 was a key protein that displayed enhanced interaction with MAD1 after DNA damage.Finally,we showed that MAD1 interaction with KU80 required serine 214 phosphorylation,and it was essential for activation of DNA protein kinases catalytic subunit(DNA-PKcs).Conclusions:MAD1 serine 214 phosphorylation mediated by ATM kinase in response to IR was required for the interaction with KU80 and activation of DNA-PKCs.
基金supported by Zhengzhou Major Collaborative Innovation Project(No.18XTZX12003)Key Projects of Discipline Construction in Zhengzhou University(No.XKZDJC202001)+2 种基金National Key Research and Development Program in China(No.2020YFC2006100)Excellent Foreign Scientist Studio of Henan Province in China(No.GZS2018001)Medical Service Capacity Improvement Project of Henan Province in China(Grant No.Yu Wei Medicine[2017]No.66).
文摘The activation of some oncogenes promote cancer cell proliferation and growth,facilitate cancer progression and metastasis by induce DNA replication stress,even genome instability.Activation of the cyclic GMP-AMP synthase(cGAS)mediates classical DNA sensing,is involved in genome instability,and is linked to various tumor development or therapy.However,the function of cGAS in gastric cancer remains elusive.In this study,the TCGA database and retrospective immunohistochemical analyses revealed substantially high cGAS expression in gastric cancer tissues and cell lines.By employing cGAS high-expression gastric cancer cell lines,including AGS and MKN45,ectopic silencing of cGAS caused a significant reduction in the proliferation of the cells,tumor growth,and mass in xenograft mice.Mechanistically,database analysis predicted a possible involvement of cGAS in the DNA damage response(DDR),further data through cells revealed protein interactions of the cGAS and MRE11-RAD50-NBN(MRN)complex,which activated cell cycle checkpoints,even increased genome instability in gastric cancer cells,thereby contributing to gastric cancer progression and sensitivity to treatment with DNA damaging agents.Furthermore,the upregulation of cGAS significantly exacerbated the prognosis of gastric cancer patients while improving radiotherapeutic outcomes.Therefore,we concluded that cGAS is involved in gastric cancer progression by fueling genome instability,implying that intervening in the cGAS pathway could be a practicable therapeutic approach for gastric cancer.
基金NIEHSGrant/Award Number:R01 ES014737+2 种基金USAMRDCGrant/Award Number:W81XWH-18-1-0353supported by the research fund from NYIT
文摘Background:Replication stress response is crucial for the maintenance of a stable ge-nome.POLDIP3(DNA polymerase delta interacting protein 3)was initially identified as one of the DNA polymeraseδ(Polδ)interacting proteins almost 20 years ago.Using a variety of in vitro biochemical assays,we previously established that POLDIP3 is a key regulator of the enzymatic activity of Polδ.However,the in vivo function of POLDIP3 in DNA replication and DNA damage response has been elusive.Methods:We first generated POLDIP3 knockout(KO)cells using the CRISPR/Cas9 technology.We then investigated its biological functions in vivo using a variety of biochemical and cell biology assays.Results:We showed that although the POLDIP3-KO cells manifest no pronounced defect in global DNA synthesis under nonstress conditions,they are sensitive to a va-riety of replication fork blockers.Intriguingly,we found that POLDIP3 plays a crucial role in the activation and maintenance of the DNA damage checkpoint in response to exogenous as well as endogenous replication stress.Conclusion:Our results indicate that when the DNA replication fork is blocked,POLDIP3 can be recruited to the stalled replication fork and functions to bridge the early DNA damage checkpoint response and the later replication fork repair/restart.
文摘Esophageal cancer(EC)was an aggressive malignant neoplasm characterized by high morbidity and poor prognosis.Identifying the changes in DNA damage repair genes helps to better understand the mechanisms of carcinoma progression.In this study,by comparing EC samples and normal samples,we found a total of 132 DDR expression with a significant difference.Moreover,we revealed higher expression of POLN,PALB2,ATM,PER1,TOP3B and lower expression of HMGB1,UBE2B were correlated to longer OS in EC.In addition,a prognostic risk score based on 7 DDR gene expression(POLN,HMGB1,TOP3B,PER1,UBE2B,ATM,PALB2)was constructed for the prognosis of EC.Meanwhile,EC cancer samples were divided into 3 subtypes based on 132 DDR genes expressions.Clinical profile analysis showed cluster C1 and C2 showed a similar frequency of T2,which was remarked higher than that in cluster 3.Moreover,we found the immune cell inflation levels were significantly changed in different subtypes of EC.The infiltration levels of T cell CD8+,B cell and NK cells were greatly higher in cluster 2 than that in cluster 1 and cluster 3.The results showed T cell CD4+infiltration levels were dramatically higher in cluster 1 than that in cluster 2 and cluster 3.Finally,we perform bioinformatics analysis of DEGs among 3 subtypes of EC and found DDR genes may be related to multiple signaling,such as Base excision repair,Cell cycle,Hedgehog signaling pathway,and Glycolysis/Gluconeogenesis.These results showed DDR genes may serve as new target for the prognosis of EC and prediction of the potential response of immune therapy in EC.
文摘Acrylamide(AA)is ubiquitous in packaging materials,paints,cosmetics,food and drinking water.However,AA has obvious neurotoxicity,reproductive toxicity and carcinogenicity,which seriously endangers human health.As one of precious traditional Chinese medicines,Gastrodia elata Bl.has been mainly used to lower blood pressure and resist myocardial ischemia.However,the antioxidant activity of Gastrodia elata Bl.on AA-induced DNA damage has not been reported.We found that AA(25,30 and 50 mg/kg)could cause DNA damage and the damage was time/dose dependent.After AA administration,Tail moment,micronuclei formation rate,8-OHdG and MDA level were significantly increased and SOD activity was decreased.Gastrodia elata Bl.decoction,gastrodin and vitamin C could reduce AA-induced DNA damage by decreasing AA-induced increment of tail moment and micronuclei formation rate.What’s more,Gastrodia elata Bl.decoction,gastrodin and vitamin C could lower 8-OHdG and MDA level and improve SOD activity.In conclusion,our research showed that Gastrodia elata Bl.decoction and gastrodin had protective effects on AA-induced DNA damage,and the potential protective mechanism might be related to anti-oxidative stress.
文摘Diagnosis and biological behavior of breast cancer of female dog represent one of the biggest challenges facing the Veterinarian in recent years. Due to its exponential growth and the degree of aggressiveness, the exact cause of this tumor is probably multifactorial and it is believed that may suffer influence from environmental factors. Among the suspected environmental contaminants are the pyrethroids. Aiming to investigate the participation of pyrethroids in tumorigenesis in female dogs, a study was conducted using 50 female dogs, 22 were positive for simple breast carcinoma (Group I), 18 with a diagnosis of complex breast carcinoma (Group II) and 10 negative (Group III) for breast cancer. In order to detect DNA damage, the Comet assay was performed on mammary samples of these animals, which also had samples submitted to the technique of High Performance Liquid Chromatography (HPLC), which aimed to quantify the concentration of pyrethroids. The results of HPLC of each animal were compared with those obtained by the Comet assay analysis of variance and the means were compared by the test groups “Student T” at the significance level of p ￡ 0.05. Despite presenting correlation between the amount of DNA damage and tumor aggressiveness, no statistical differences were found in the DNA damage of different histologic types of breast carcinoma. As for pyrethroids, even these were detected in 22% of tumor tissues and peritumoral fat, there was no difference in DNA damage between cells exposed and not exposed to environmental contaminant.
文摘Oxidative stress has been implicated in the inflammatory process of Systemic Lupus Erythematosus (SLE), particularly by the formation of anti-DNA autoantibodies, which can lead to DNA damage. The aim of this study was to investigate, through comet assay, whether the level of DNA damage in SLE patients is different from that of healthy subjects. Twenty-five adult SLE patients with SLEDAI up to ten, and 25 healthy subjects were paired according to age, gender and Body Mass Index (BMI). Other anthropometric variables were also assessed. Comet assay was assessed as the marker of oxidative stress described as DNA Damage (DD) percentage. Waist Circumference (WC), Hip Circumference (HC) and BMI were also performed. Exclusion criteria for patients and controls comprised smoking and other chronic disorders. Level of damage index was remarkably higher in SLE patients than in controls, and no significant differences between the groups were found for age, BMI, WC and HC. No stratification concerning gender was performed, since there were just two males per group. No correlation was observed between BMI and DD (%). DD increased in SLE, which reflects the oxidant/antioxidant imbalance in these patients. These findings support an association between oxidative stress and SLE. This stronger correlation observed in patients with low disease activity may be useful in elucidating the mechanisms of disease pathogenesis.
基金supported by the Natural Science Foundation of Guangxi in China(No.2021GXNSFDA220001)Baise Engineering Technology Research Center(No.20212210)2022 Scientific Research and Technological Development Foundation of Baise in China(No.20221403)。
文摘Aluminum(Al)can lead to an exposure of creature in varieties ways for its universality,and it could disturb normal physiological metabolism,with the damage to multisystem including reproduction.Since the oocyte quality is critical for female reproduction,we inspected the toxicity of Al on mouse oocyte maturation.We constructed in vitro exposure mouse model,and we found that 5 mmol/L Al had adverse effects on oocyte maturation by impairing organelle and cytoskeleton.Aberrant spindle and misaligned chromosomes which might be considered to be caused by elevated levels of acetylation,as well as abnormal distribution of actin dynamics could hinder normal meiosis of oocytes.Organelle dysfunction indicated that Al affected proteins synthesis,transport and digestion,which would further damage oocyte maturation.In order to explore the mechanism of Al toxicity,our further investigation demonstrated that Al caused mitochondrial dysfunction and imbalance calcium homeostasis,resulting in limited energy supply.Moreover,high level of reactive oxygen species,DNA damage and apoptosis caused by oxidative stress were also the manifestation of Al toxicity on oocytes.In conclusion,our study provided the evidence that Al exposure affected oocyte quality through its effects on spindle organization,actin dynamics,organelle function and the induction of DNA damage-related apoptosis with mouse model.
基金funded by National Key Research and Development Program of China(2022YFB3203804,2022YFB3203801,2022YFB3203800)the Leading Talent of“Ten Thousand Plan”National High-Level Talents Special Support Plan,National Natural Science Foundation of China(32071374,32000985)+4 种基金Program of Shanghai Academic Research Leader under the Science and Technology Innovation Action Plan(21XD1422100,China)Program of Shanghai Science and Technology Development(22TS1400700,China)Zhejiang Provincial Natural Science Foundation of China(LR22C100001,LQ21H300003,China)Innovative Research Team of High-Level Local Universities in Shanghai(SHSMU-ZDCX20210900,China)CAS Interdisciplinary Innovation Team(JCTD-2020-08,China)。
文摘Cancer,a complex and heterogeneous disease,arises from genomic instability.Currently,DNA damage-based cancer treatments,including radiotherapy and chemotherapy,are employed in clinical practice.However,the efficacy and safety of these therapies are constrained by various factors,limiting their ability to meet current clinical demands.Metal nanoparticles present promising avenues for enhancing each critical aspect of DNA damage-based cancer therapy.Their customizable physicochemical properties enable the development of targeted and personalized treatment platforms.In this review,we delve into the design principles and optimization strategies of metal nanoparticles.We shed light on the limitations of DNA damage-based therapy while highlighting the diverse strategies made possible by metal nanoparticles.These encompass targeted drug delivery,inhibition of DNA repair mechanisms,induction of cell death,and the cascading immune response.Moreover,we explore the pivotal role of physicochemical factors such as nanoparticle size,stimuli-responsiveness,and surface modification in shaping metal nanoparticle platforms.Finally,we present insights into the challenges and future directions of metal nanoparticles in advancing DNA damage-based cancer therapy,paving the way for novel treatment paradigms.
基金supported by the National Science Foundation of China(82130011,81770261,91749128,and 81900233)the Fundamental Research Funds for the Central Universities(2042022kf1125,China)the Outstanding Young and Middleaged Talents Training Program of Zhongnan Hospital of Wuhan University(ZNYQ2022002,China).
文摘Clinical application of doxorubicin(DOX)is heavily hindered by DOX cardiotoxicity.Several theories were postulated for DOX cardiotoxicity including DNA damage and DNA damage response(DDR),although the mechanism(s)involved remains to be elucidated.This study evaluated the potential role of TBC domain family member 15(TBC1D15)in DOX cardiotoxicity.Tamoxifen-induced cardiac-specific Tbcldi5 knockout(Tbcldi5^(CKO))or Tbcldi5 knockin(Tbcldi5^(CKI))male mice were challenged with a single dose of DOx prior to cardiac assessment 1 week or 4 weeks following DOX challenge.Adenoviruses encoding TBC1D15 or containing shRNA targeting Tbcld15 were used for Tbcld15 overexpression or knockdown in isolated primary mouse cardiomyocytes.Our results re-vealed that DOX evoked upregulation of TBC1D15 with compromised myocardial function and overt mortality,the effects of which were ameliorated and accentuated by Tbcldi5 deletion and Tbcld15 overexpression,respectively.DOX overtly evoked apoptotic cell death,the effect of which was alleviated and exacerbated by Tbcld15 knockout and overexpression,respectively.Meanwhile,DOX provoked mitochondrial membrane potential collapse,oxidative stress and DNA damage,the effects of which were mitigated and exacerbated by Tbcld15 knockdown and overexpression,respectively.Further scrutiny revealed that TBC1D15 fostered cytosolic accumulation of the cardinal DDR element DNA-dependent protein kinase catalytic subunit(DNA-PKcs).Liquid chromatography-tandem mass spectrometry and coimmunoprecipitation denoted an interaction between TBCID15 and DNA-PKcs at the segment 594-624 of TBC1D15.Moreover,overexpression of TBC1D15 mutant(A594-624,deletion of segment 594-624)failed to elicit accentuation of DOX-induced cytosolic retention of DNA-PKcs,DNA damage and cardiomyocyte apoptosis by TBC1D15 wild type.However,Tbcld15 deletion ameliorated DOXinduced cardiomyocyte contractile anomalies,apoptosis,mitochondrial anomalies,DNA damage and cytosolic DNA-PKcs accumulation,which were canceled off by DNA-PKcs inhibition or ATM activation.Taken together,our findings denoted a pivotal role for TBCID15 in DOX-induced DNA damage,mitochondrial injury,and apoptosis possibly through binding with DNA-PKcs and thus gate-keeping its cytosolic retention,a route to accentuation of cardiac contractile dysfunction in DOX-induced cardiotoxicity.
