With the rapid development of science and technology,cell-free DNA(cfDNA)is rapidly becoming an important biomarker for tumor diagnosis,monitoring and prognosis,and this cfDNA-based liquid biopsy technology has great ...With the rapid development of science and technology,cell-free DNA(cfDNA)is rapidly becoming an important biomarker for tumor diagnosis,monitoring and prognosis,and this cfDNA-based liquid biopsy technology has great potential to become an important part of precision medicine.cfDNA is the total amount of free DNA in the systemic circulation,including DNA fragments derived from tumor cells and all other somatic cells.Tumor cells release fragments of DNA into the bloodstream,and this source of cfDNA is called circulating tumor DNA(ctDNA).cfDNA detection has become a major focus in the field of tumor research in recent years,which provides a new opportunity for non-invasive diagnosis and prognosis of cancer.In this paper,we discuss the limitations of the study on the origin and dynamics analysis of ctDNA,and how to solve these problems in the future.Although the future faces major challenges,it also con-tains great potential.展开更多
Hepatocellular carcinoma(HCC) is considered the fifth most prevalent cancer among all types of cancers and has the third most morbidity value. It has the most frequent duplication time and a high recurrence rate. Rece...Hepatocellular carcinoma(HCC) is considered the fifth most prevalent cancer among all types of cancers and has the third most morbidity value. It has the most frequent duplication time and a high recurrence rate. Recently, the most unique technique used is liquid biopsies, which carry many markers;the most prominent is circulating tumor DNA(ctDNA). Varied methods are used to investigate ctDNA, including various forms of polymerase chain reaction(PCR) [emulsion PCR(ePCR), digital PCR(dPCR), and bead, emulsion, amplification, magnetic(BEAMing) PCR]. Hence ctDNA is being recognized as a potential biomarker that permits early cancer detection,treatment monitoring, and predictive data on tumor burden are subjective to therapy or surgery. Numerous ctDNA biomarkers have been investigated based on their alterations such as 1) single nucleotide variations(either insertion or deletion of a nucleotide) markers including TP53, KRAS, and CCND1;2) copy number variations which include markers such as CDK6, EFGR, MYC and BRAF;3) DNA methylation(RASSF1A, SEPT9, KMT2C and CCNA2);4) homozygous mutation includes ctDNA markers as CDKN2A, AXIN1;and 5) gain or loss of function of the genes, particularly for HCC. Various researchers have conducted many studies and gotten fruitful results.Still, there are some drawbacks to ctDNA namely low quantity, fragment heterogeneity, less stability, limited mutant copies and standards, and differential sensitivity. However, plenty of investigations demonstrate ctDNA's significance as a polyvalent biomarker for cancer and can be viewed as a future diagnostic, prognostic and therapeutic agent. This article overviews many conditions in genetic changes linked to the onset and development of HCC, such as dysregulated signaling pathways, somatic mutations, single-nucleotide polymorphisms, and genomic instability. Additionally, efforts are also made to develop treatments for HCC that are molecularly targeted and to unravel some of the genetic pathways that facilitate its early identification.展开更多
BACKGROUND Endometrial cancer(EC)is a common gynecological malignancy that typically requires prompt surgical intervention;however,the advantage of surgical management is limited by the high postoperative recurrence r...BACKGROUND Endometrial cancer(EC)is a common gynecological malignancy that typically requires prompt surgical intervention;however,the advantage of surgical management is limited by the high postoperative recurrence rates and adverse outcomes.Previous studies have highlighted the prognostic potential of circulating tumor DNA(ctDNA)monitoring for minimal residual disease in patients with EC.AIM To develop and validate an optimized ctDNA-based model for predicting shortterm postoperative EC recurrence.METHODS We retrospectively analyzed 294 EC patients treated surgically from 2015-2019 to devise a short-term recurrence prediction model,which was validated on 143 EC patients operated between 2020 and 2021.Prognostic factors were identified using univariate Cox,Lasso,and multivariate Cox regressions.A nomogram was created to predict the 1,1.5,and 2-year recurrence-free survival(RFS).Model performance was assessed via receiver operating characteristic(ROC),calibration,and decision curve analyses(DCA),leading to a recurrence risk stratification system.RESULTS Based on the regression analysis and the nomogram created,patients with postoperative ctDNA-negativity,postoperative carcinoembryonic antigen 125(CA125)levels of<19 U/mL,and grade G1 tumors had improved RFS after surgery.The nomogram’s efficacy for recurrence prediction was confirmed through ROC analysis,calibration curves,and DCA methods,highlighting its high accuracy and clinical utility.Furthermore,using the nomogram,the patients were successfully classified into three risk subgroups.CONCLUSION The nomogram accurately predicted RFS after EC surgery at 1,1.5,and 2 years.This model will help clinicians personalize treatments,stratify risks,and enhance clinical outcomes for patients with EC.展开更多
Liquid biopsy,including both circulating tumor cells and circulating tumor DNA,is becoming more popular as a diagnostic tool in the clinical management of breast cancer.Elevated concentrations of these biomarkers duri...Liquid biopsy,including both circulating tumor cells and circulating tumor DNA,is becoming more popular as a diagnostic tool in the clinical management of breast cancer.Elevated concentrations of these biomarkers during cancer treatment may be used as markers for cancer progression as well as to understand the mechanisms underlying metastasis and treatment resistance.Thus,these circulating markers serve as tools for cancer assessing and monitoring through a simple,non-invasive blood draw.However,despite several study results currently noting a potential clinical impact of ctDNA mutation tracking,the method is not used clinically in cancer diagnosis among patients and more studies are required to confirm it.This review focuses on understanding circulating tumor biomarkers,especially in breast cancer.展开更多
Cancer is a common cause of death worldwide.Despite significant advances in cancer treatments,the morbidity and mortality are still enormous.Tumor heterogeneity,especially intratumoral heterogeneity,is a significant r...Cancer is a common cause of death worldwide.Despite significant advances in cancer treatments,the morbidity and mortality are still enormous.Tumor heterogeneity,especially intratumoral heterogeneity,is a significant reason underlying difficulties in tumor treatment and failure of a number of current therapeutic modalities,even of molecularly targeted therapies.The development of a virtually noninvasive "liquid biopsy" from the blood has been attempted to characterize tumor heterogeneity.This review focuses on cell-free circulating tumor DNA(ctDNA) in the bloodstream as a versatile biomarker.ctDNA analysis is an evolving field with many new methods being developed and optimized to be able to successfully extract and analyze ctDNA,which has vast clinical applications.ctDNA has the potential to accurately genotype the tumor and identify personalized genetic and epigenetic alterations of the entire tumor.In addition,ctDNA has the potential to accurately monitor tumor burden and treatment response,while also being able to monitor minimal residual disease,reducing the need for harmful adjuvant chemotherapy and allowing more rapid detection of relapse.There are still many challenges that need to be overcome prior to this biomarker getting wide adoption in the clinical world,including optimization,standardization,and large multicenter trials.展开更多
Most pancreatic cancer patients present with advanced metastatic disease, resulting in extremely poor 5-year survival, mainly because of the lack of a reliable modality for early detection and limited therapeutic opti...Most pancreatic cancer patients present with advanced metastatic disease, resulting in extremely poor 5-year survival, mainly because of the lack of a reliable modality for early detection and limited therapeutic options for advanced disease. Therefore, there is a need for minimally-invasive diagnostic tools for detecting pancreatic cancer at an early stage, when curative surgery and also novel therapeutic approaches including precision medicine may be feasible. The "liquid biopsy" addresses these unmet clinical needs based on the concept that simple peripheral blood sampling and detection of circulating tumor DNA(ct DNA) could provide diagnostic information. In this review, we provide an overview of the current status of bloodbased tests for diagnosis of pancreatic cancer and the potential utility of ct DNA for precision medicine. We also discuss challenges that remain to be addressed in developing practical ct DNA-based liquid biopsy approaches for early diagnosis of pancreatic cancer.展开更多
BACKGROUND One of the most notable applications for circulating tumor DNA(ctDNA)detection in peripheral blood of patients with metastatic colorectal cancer(mCRC)is a long-term postoperative follow-up.Sometimes referre...BACKGROUND One of the most notable applications for circulating tumor DNA(ctDNA)detection in peripheral blood of patients with metastatic colorectal cancer(mCRC)is a long-term postoperative follow-up.Sometimes referred to as a“liquid(re)biopsy”it is a minimally invasive procedure and can be performed repeatedly at relatively short intervals(months or even weeks).The presence of the disease and the actual extent of the tumor burden(tumor mass)within the patient’s body can be monitored.This is of particular importance,especially when evaluating radicality of surgical treatment as well as for early detection of disease progression or recurrence.AIM To confirm the radicality of surgery using ctDNA and compare available methods for detection of recurrence in metastatic colorectal cancer.METHODSA total of 47 patients with detected ctDNA and indications for resection of mCRC were enrolled in the multicenter study involving three surgical centers.Standard postoperative follow-ups using imaging techniques and the determination of tumor markers were supplemented by ctDNA sampling.In addition to the baseline ctDNA testing prior to surgery,a postoperative observation was conducted by evaluating ctDNA presence up to a week after surgery and subsequently at approximately three-month intervals.The presence of ctDNA was correlated with radicality of surgical treatment and the actual clinical status of the patient.RESULTS Among the monitored patients,the R0(curative)resection correlated with postoperative ctDNA negativity in 26 out of 28 cases of surgical procedures(26/28,93%).In the remaining cases of R0 surgeries that displayed ctDNA,both patients were diagnosed with a recurrence of the disease after 6 months.In 7 patients who underwent an R1 resection,4 ctDNA positivities(4/7,57%)were detected after surgery and associated with the confirmation of early disease recurrence(after 3 to 7 months).All 15 patients(15/15,100%)undergoing R2 resection remained constantly ctDNA positive during the entire follow-up period.In 22 cases of recurrence,ctDNA positivity was detected 22 times(22/22,100%)compared to 16 positives(16/22,73%)by imaging methods and 15 cases(15/22,68%)of elevated tumor markers.CONCLUSION ctDNA detection in patients with mCRC is a viable tool for early detection of disease recurrence as well as for confirmation of the radicality of surgical treatment.展开更多
BACKGROUND It remains unclear which factors,such as tumor volume and tumor invasion,influence circulating tumor DNA(ctDNA),and the origin of ctDNA in liquid biopsy is always problematic.To use liquid biopsies clinical...BACKGROUND It remains unclear which factors,such as tumor volume and tumor invasion,influence circulating tumor DNA(ctDNA),and the origin of ctDNA in liquid biopsy is always problematic.To use liquid biopsies clinically,it will be very important to address these questions.AIM To assess the origin of ctDNA,clarify the dynamics of ctDNA levels,assess ctDNA levels by using a xenograft mouse after treatment,and to determine whether tumor volume and invasion are related to ctDNA levels.METHODS Tumor xenotransplants were established by inoculating BALB/c-nu/nu mice with the TE11 cell line.Groups of mice were injected with xenografts at two or four sites and sacrificed at the appropriate time point after xenotransplantation for ctDNA analysis.Analysis of ctDNA was performed by droplet digital PCR,using the human telomerase reverse transcriptase(hTERT)gene.RESULTS Mice given two-site xenografts were sacrificed for ctDNA at week 4 and week 8.No hTERT was detected at week 4,but it was detected at week 8.However,in four-site xenograft mice,hTERT was detected both at week 4 and week 6.These experiments revealed that both tumor invasion and tumor volume were asso ciated with the detection of ctDNA.In resection experiments,hTERT was detected at resection,but had decreased by 6 h,and was no longer detected 1 and 3 d after resection.CONCLUSION We clarified the origin and dynamics of ctDNA,showing that tumor volume is an important factor.We also found that when the tumor was completely resected,ctDNA was absent after one or more days.展开更多
Minimally invasive detection of circulating tumor DNA(ctDNA)in peripheral blood or other body fluids of patients with gastrointestinal malignancies via liquid biopsy has emerged as a promising biomarker.This is urgent...Minimally invasive detection of circulating tumor DNA(ctDNA)in peripheral blood or other body fluids of patients with gastrointestinal malignancies via liquid biopsy has emerged as a promising biomarker.This is urgently needed,as conventional imaging and plasma protein-derived biomarkers lack sensitivity and specificity in prognosis,early detection of relapse or treatment monitoring.This review summarizes the potential role of liquid biopsy in diagnosis,prognosis and treatment monitoring of gastrointestinal malignancies,including upper gastrointestinal,liver,bile duct,pancreatic and colorectal cancer.CtDNA can now be part of the clinical routine as a promising,highly sensitive and specific biomarker with a broad range of applicability.Liquid-biopsy based postoperative relapse prediction could lead to improved survival by intensification of adjuvant treatment in patients identified to be at risk of early recurrence.Moreover,ctDNA allows monitoring of antineoplastic treatment success,with identification of potentially developed resistance or therapeutic targets during the course of treatment.It may also assist in early change of chemotherapy in metastatic gastrointestinal malignancies prior to imaging findings of relapse.Nevertheless,clinical utility is dependent on the tumor’s entity and burden.展开更多
For many years tissue biopsy has been the primary procedure to establish cancer diagnosis and determine further treatment and prognosis.However,this method has multiple drawbacks,including,to mention some,being an inv...For many years tissue biopsy has been the primary procedure to establish cancer diagnosis and determine further treatment and prognosis.However,this method has multiple drawbacks,including,to mention some,being an invasive procedure carrying significant risk for fragile patients and allowing only for a“snapshot”of the tumor biology in time.The process of liquid biopsy allows for a minimally invasive procedure that provides molecular information about underlying cancer by analyzing circulating tumor DNA(ctDNA)via next-generation sequencing technology and circulating tumor cells.This paper focuses on describing the basis of ctDNA and its current utilities.展开更多
BACKGROUND Patients diagnosed with non-small-cell lung cancer with activated epidermal growth factor receptor mutations are more likely to develop leptomeningeal(LM)metastasis than other types of lung cancers and have...BACKGROUND Patients diagnosed with non-small-cell lung cancer with activated epidermal growth factor receptor mutations are more likely to develop leptomeningeal(LM)metastasis than other types of lung cancers and have a poor prognosis.Early diagnosis and effective treatment of leptomeningeal carcinoma can improve the prognosis.CASE SUMMARY A 55-year-old female with a progressive headache and vomiting for one month was admitted to Peking University First Hospital.She was diagnosed with lung adenocarcinoma with osseous metastasis 10 months prior to admittance.epidermal growth factor receptor(EGFR)mutation was detected by genomic examination,so she was first treated with gefitinib for 10 months before acquiring resistance.Cell-free cerebrospinal fluid(CSF)circulating tumor DNA detection by next-generation sequencing was conducted and indicated the EGFR-Thr790Met mutation,while biopsy and cytology from the patient’s CSF and the first enhanced cranial magnetic resonance imaging(MRI)showed no positive findings.A month later,the enhanced MRI showed linear leptomeningeal enhancement,and the cytology and biochemical examination in CSF remained negative.Therefore,osimertinib(80 mg/d)was initiated as a second-line treatment,resulting in a good response within a month.CONCLUSION This report suggests clinical benefit of osimertinib in LM patients with positive detection of the EGFR-Thr790Met mutation in CSF and proposes that the positive findings of CSF circulating tumor DNA as a liquid biopsy technology based on the detection of cancer-associated gene mutations may appear earlier than the imaging and CSF findings and may thus be helpful for therapy.Moreover,the routine screening of chest CT with the novel coronavirus may provide unexpected benefits。展开更多
Objectives: Circulating tumor DNA (ctDNA) is shown to provide the real-time genomic information of metastatic breast cancer. This study elucidates the clinico-pathological significance of ctDNA in early-stage breast c...Objectives: Circulating tumor DNA (ctDNA) is shown to provide the real-time genomic information of metastatic breast cancer. This study elucidates the clinico-pathological significance of ctDNA in early-stage breast cancer using the PIK3CA mutation as an indicator. Materials and Methods: Twenty-seven primary breast cancers without metastasis were surgically resected and pathologically diagnosed at the University of Tokyo Hospital, Japan. Genomic DNA of primary tumor was extracted from formalin-fixed and paraffin-embedded specimens. ctDNA was extracted from fresh-frozen plasma from patients. The PIK3CA mutations at E542K, E545K and H1047R were examined by Sanger sequencing or droplet digital PCR in 27 tumors and pre- and post-surgery plasma. Results: The PIK3CA mutations were detected in 13 (48%) of 27 primary tumors. These mutations did not significantly correlate with specific clinico-pathological characteristics of tumors. When ctDNA was examined, 4 (33%) of 12 cases carrying the mutated PIK3CA showed the identical mutation in pre-surgery plasma and 2 (50%) of them showed the identical mutations in post-surgery plasma. Interestingly, in these 2 cases in pathological stages IIIA and IA, fractional abundance of the mutated PIK3CA alleles to the total alleles in pre-surgery ctDNA was around 1% or more and was higher than that of the other two cases without PIK3CA mutations in post-surgery ctDNA. Conclusions: The PIK3CA mutation in ctDNA is detectable even in a subset of early-stage breast cancer. Furthermore, fractional abundance of the mutated PIK3CA in pre-surgery ctDNA could provide a possible predictive indicator for tumor burden and for choosing the appropriate adjuvant treatment of breast cancer.展开更多
BACKGROUND The poly(ADP-ribose)polymerase(PARP)inhibitor olaparib has displayed superior clinical effect in metastatic castration-resistant prostate cancer(mCRPC)patients with the homologous recombination repair(HRR)g...BACKGROUND The poly(ADP-ribose)polymerase(PARP)inhibitor olaparib has displayed superior clinical effect in metastatic castration-resistant prostate cancer(mCRPC)patients with the homologous recombination repair(HRR)genes mutations.However,when a patient’s tumor tissue volume is insufficient for genomic profiling of HRR gene mutations,circulating tumor DNA(ctDNA)may be useful in helping to determine and monitor the efficacy of olaparib,as well as in abiraterone-combination treatment,and for understanding any resistance mechanism related to such mutations.CASE SUMMARY A 61-year-old man who was diagnosed with metastatic prostate adenocarcinoma was initially hormone sensitivity,showing high Gleason score(5+5=10)and absolute positive rate(14/14 biopsied specimens).Following failure of several standard therapies,the patient progressed to mCRPC.Surprisingly,the patient showed good response to olaparib-abiraterone-prednisone combination treatment(an androgen-deprivation therapy,provided as the‘final choice’in China).Serum total prostate-specific antigen(TPSA)level reduced and symptoms remitted for 4 months.However,thereafter,serum TPSA levels began slowly increasing,indicating development of olaparib resistance.Subsequent comprehensive genomic profiling of ctDNA, screening 508 cancer-related genes by next-generation sequencing,identified 10 somatic variants as well as 3 copy number alterations. Two identified reversemissense mutations in partner and localizer of BRCA2 (PALB2) may have recovered the readingframe, restoring function of the primary germline PALB2 mutation and causing resistance to thePARP inhibitor olaparib.CONCLUSIONReverse mutations in PALB2, discovered via genomic profiling of ctDNA, may represent apotential resistance mechanism against olaparib in mCRPC.展开更多
Objective:This study aimed to investigate the relationship between circulating tumor DNA and epithelial ovarian cancer.Methods:Twenty-seven cases with epithelial ovarian cancer in changle people's hospital in shan...Objective:This study aimed to investigate the relationship between circulating tumor DNA and epithelial ovarian cancer.Methods:Twenty-seven cases with epithelial ovarian cancer in changle people's hospital in shandong province were collected.Blood samples before operation were collected to detect circulating tumor DNA.Results:There are 22 ctDNA positive cases,with a proportion of 81.5%(22/27).Proportion of ctDNA positive patients before operation in the early and advanced stage was 60%and 94.1%respectively,with a statistically significant difference(P<0.05).The difference of proportion of ctDNA positive patients before operation in the subgroup analysis based on clinical stage,histological grading,pathological types,and tumor size was statistically significant(P<0.05).Conclusion:CtDNA is a promising tumor marker associated with epithelial ovarian cancer.展开更多
基金Supported by Talent Scientific Research Start-up Foundation of Wannan Medical College,No.WYRCQD2023045.
文摘With the rapid development of science and technology,cell-free DNA(cfDNA)is rapidly becoming an important biomarker for tumor diagnosis,monitoring and prognosis,and this cfDNA-based liquid biopsy technology has great potential to become an important part of precision medicine.cfDNA is the total amount of free DNA in the systemic circulation,including DNA fragments derived from tumor cells and all other somatic cells.Tumor cells release fragments of DNA into the bloodstream,and this source of cfDNA is called circulating tumor DNA(ctDNA).cfDNA detection has become a major focus in the field of tumor research in recent years,which provides a new opportunity for non-invasive diagnosis and prognosis of cancer.In this paper,we discuss the limitations of the study on the origin and dynamics analysis of ctDNA,and how to solve these problems in the future.Although the future faces major challenges,it also con-tains great potential.
基金supported by National Natural Science Foundation of China (No. 31902287)Key R&D and Promotion Projects of Henan Province (No. 242102310467, No. 242102310240 and No. 23210 2310132)Henan Department of Public Health (No. LHGJ20221021)。
文摘Hepatocellular carcinoma(HCC) is considered the fifth most prevalent cancer among all types of cancers and has the third most morbidity value. It has the most frequent duplication time and a high recurrence rate. Recently, the most unique technique used is liquid biopsies, which carry many markers;the most prominent is circulating tumor DNA(ctDNA). Varied methods are used to investigate ctDNA, including various forms of polymerase chain reaction(PCR) [emulsion PCR(ePCR), digital PCR(dPCR), and bead, emulsion, amplification, magnetic(BEAMing) PCR]. Hence ctDNA is being recognized as a potential biomarker that permits early cancer detection,treatment monitoring, and predictive data on tumor burden are subjective to therapy or surgery. Numerous ctDNA biomarkers have been investigated based on their alterations such as 1) single nucleotide variations(either insertion or deletion of a nucleotide) markers including TP53, KRAS, and CCND1;2) copy number variations which include markers such as CDK6, EFGR, MYC and BRAF;3) DNA methylation(RASSF1A, SEPT9, KMT2C and CCNA2);4) homozygous mutation includes ctDNA markers as CDKN2A, AXIN1;and 5) gain or loss of function of the genes, particularly for HCC. Various researchers have conducted many studies and gotten fruitful results.Still, there are some drawbacks to ctDNA namely low quantity, fragment heterogeneity, less stability, limited mutant copies and standards, and differential sensitivity. However, plenty of investigations demonstrate ctDNA's significance as a polyvalent biomarker for cancer and can be viewed as a future diagnostic, prognostic and therapeutic agent. This article overviews many conditions in genetic changes linked to the onset and development of HCC, such as dysregulated signaling pathways, somatic mutations, single-nucleotide polymorphisms, and genomic instability. Additionally, efforts are also made to develop treatments for HCC that are molecularly targeted and to unravel some of the genetic pathways that facilitate its early identification.
文摘BACKGROUND Endometrial cancer(EC)is a common gynecological malignancy that typically requires prompt surgical intervention;however,the advantage of surgical management is limited by the high postoperative recurrence rates and adverse outcomes.Previous studies have highlighted the prognostic potential of circulating tumor DNA(ctDNA)monitoring for minimal residual disease in patients with EC.AIM To develop and validate an optimized ctDNA-based model for predicting shortterm postoperative EC recurrence.METHODS We retrospectively analyzed 294 EC patients treated surgically from 2015-2019 to devise a short-term recurrence prediction model,which was validated on 143 EC patients operated between 2020 and 2021.Prognostic factors were identified using univariate Cox,Lasso,and multivariate Cox regressions.A nomogram was created to predict the 1,1.5,and 2-year recurrence-free survival(RFS).Model performance was assessed via receiver operating characteristic(ROC),calibration,and decision curve analyses(DCA),leading to a recurrence risk stratification system.RESULTS Based on the regression analysis and the nomogram created,patients with postoperative ctDNA-negativity,postoperative carcinoembryonic antigen 125(CA125)levels of<19 U/mL,and grade G1 tumors had improved RFS after surgery.The nomogram’s efficacy for recurrence prediction was confirmed through ROC analysis,calibration curves,and DCA methods,highlighting its high accuracy and clinical utility.Furthermore,using the nomogram,the patients were successfully classified into three risk subgroups.CONCLUSION The nomogram accurately predicted RFS after EC surgery at 1,1.5,and 2 years.This model will help clinicians personalize treatments,stratify risks,and enhance clinical outcomes for patients with EC.
文摘Liquid biopsy,including both circulating tumor cells and circulating tumor DNA,is becoming more popular as a diagnostic tool in the clinical management of breast cancer.Elevated concentrations of these biomarkers during cancer treatment may be used as markers for cancer progression as well as to understand the mechanisms underlying metastasis and treatment resistance.Thus,these circulating markers serve as tools for cancer assessing and monitoring through a simple,non-invasive blood draw.However,despite several study results currently noting a potential clinical impact of ctDNA mutation tracking,the method is not used clinically in cancer diagnosis among patients and more studies are required to confirm it.This review focuses on understanding circulating tumor biomarkers,especially in breast cancer.
基金supported partly by the National Natural Science Foundation of China(No.81227901)the Natural Science Basic Research Plan in Shaanxi Province of China(No.2015JZ019)+1 种基金the Fundamental Research Funds for the Central Universities,National Cancer Institute of the National Institutes of Health(No.R00CA138914)National Natural Science Foundation(No. 81372216)
文摘Cancer is a common cause of death worldwide.Despite significant advances in cancer treatments,the morbidity and mortality are still enormous.Tumor heterogeneity,especially intratumoral heterogeneity,is a significant reason underlying difficulties in tumor treatment and failure of a number of current therapeutic modalities,even of molecularly targeted therapies.The development of a virtually noninvasive "liquid biopsy" from the blood has been attempted to characterize tumor heterogeneity.This review focuses on cell-free circulating tumor DNA(ctDNA) in the bloodstream as a versatile biomarker.ctDNA analysis is an evolving field with many new methods being developed and optimized to be able to successfully extract and analyze ctDNA,which has vast clinical applications.ctDNA has the potential to accurately genotype the tumor and identify personalized genetic and epigenetic alterations of the entire tumor.In addition,ctDNA has the potential to accurately monitor tumor burden and treatment response,while also being able to monitor minimal residual disease,reducing the need for harmful adjuvant chemotherapy and allowing more rapid detection of relapse.There are still many challenges that need to be overcome prior to this biomarker getting wide adoption in the clinical world,including optimization,standardization,and large multicenter trials.
文摘Most pancreatic cancer patients present with advanced metastatic disease, resulting in extremely poor 5-year survival, mainly because of the lack of a reliable modality for early detection and limited therapeutic options for advanced disease. Therefore, there is a need for minimally-invasive diagnostic tools for detecting pancreatic cancer at an early stage, when curative surgery and also novel therapeutic approaches including precision medicine may be feasible. The "liquid biopsy" addresses these unmet clinical needs based on the concept that simple peripheral blood sampling and detection of circulating tumor DNA(ct DNA) could provide diagnostic information. In this review, we provide an overview of the current status of bloodbased tests for diagnosis of pancreatic cancer and the potential utility of ct DNA for precision medicine. We also discuss challenges that remain to be addressed in developing practical ct DNA-based liquid biopsy approaches for early diagnosis of pancreatic cancer.
基金Supported by the Ministry of Health of the Czech Republic,No.15-27939A
文摘BACKGROUND One of the most notable applications for circulating tumor DNA(ctDNA)detection in peripheral blood of patients with metastatic colorectal cancer(mCRC)is a long-term postoperative follow-up.Sometimes referred to as a“liquid(re)biopsy”it is a minimally invasive procedure and can be performed repeatedly at relatively short intervals(months or even weeks).The presence of the disease and the actual extent of the tumor burden(tumor mass)within the patient’s body can be monitored.This is of particular importance,especially when evaluating radicality of surgical treatment as well as for early detection of disease progression or recurrence.AIM To confirm the radicality of surgery using ctDNA and compare available methods for detection of recurrence in metastatic colorectal cancer.METHODSA total of 47 patients with detected ctDNA and indications for resection of mCRC were enrolled in the multicenter study involving three surgical centers.Standard postoperative follow-ups using imaging techniques and the determination of tumor markers were supplemented by ctDNA sampling.In addition to the baseline ctDNA testing prior to surgery,a postoperative observation was conducted by evaluating ctDNA presence up to a week after surgery and subsequently at approximately three-month intervals.The presence of ctDNA was correlated with radicality of surgical treatment and the actual clinical status of the patient.RESULTS Among the monitored patients,the R0(curative)resection correlated with postoperative ctDNA negativity in 26 out of 28 cases of surgical procedures(26/28,93%).In the remaining cases of R0 surgeries that displayed ctDNA,both patients were diagnosed with a recurrence of the disease after 6 months.In 7 patients who underwent an R1 resection,4 ctDNA positivities(4/7,57%)were detected after surgery and associated with the confirmation of early disease recurrence(after 3 to 7 months).All 15 patients(15/15,100%)undergoing R2 resection remained constantly ctDNA positive during the entire follow-up period.In 22 cases of recurrence,ctDNA positivity was detected 22 times(22/22,100%)compared to 16 positives(16/22,73%)by imaging methods and 15 cases(15/22,68%)of elevated tumor markers.CONCLUSION ctDNA detection in patients with mCRC is a viable tool for early detection of disease recurrence as well as for confirmation of the radicality of surgical treatment.
文摘BACKGROUND It remains unclear which factors,such as tumor volume and tumor invasion,influence circulating tumor DNA(ctDNA),and the origin of ctDNA in liquid biopsy is always problematic.To use liquid biopsies clinically,it will be very important to address these questions.AIM To assess the origin of ctDNA,clarify the dynamics of ctDNA levels,assess ctDNA levels by using a xenograft mouse after treatment,and to determine whether tumor volume and invasion are related to ctDNA levels.METHODS Tumor xenotransplants were established by inoculating BALB/c-nu/nu mice with the TE11 cell line.Groups of mice were injected with xenografts at two or four sites and sacrificed at the appropriate time point after xenotransplantation for ctDNA analysis.Analysis of ctDNA was performed by droplet digital PCR,using the human telomerase reverse transcriptase(hTERT)gene.RESULTS Mice given two-site xenografts were sacrificed for ctDNA at week 4 and week 8.No hTERT was detected at week 4,but it was detected at week 8.However,in four-site xenograft mice,hTERT was detected both at week 4 and week 6.These experiments revealed that both tumor invasion and tumor volume were asso ciated with the detection of ctDNA.In resection experiments,hTERT was detected at resection,but had decreased by 6 h,and was no longer detected 1 and 3 d after resection.CONCLUSION We clarified the origin and dynamics of ctDNA,showing that tumor volume is an important factor.We also found that when the tumor was completely resected,ctDNA was absent after one or more days.
文摘Minimally invasive detection of circulating tumor DNA(ctDNA)in peripheral blood or other body fluids of patients with gastrointestinal malignancies via liquid biopsy has emerged as a promising biomarker.This is urgently needed,as conventional imaging and plasma protein-derived biomarkers lack sensitivity and specificity in prognosis,early detection of relapse or treatment monitoring.This review summarizes the potential role of liquid biopsy in diagnosis,prognosis and treatment monitoring of gastrointestinal malignancies,including upper gastrointestinal,liver,bile duct,pancreatic and colorectal cancer.CtDNA can now be part of the clinical routine as a promising,highly sensitive and specific biomarker with a broad range of applicability.Liquid-biopsy based postoperative relapse prediction could lead to improved survival by intensification of adjuvant treatment in patients identified to be at risk of early recurrence.Moreover,ctDNA allows monitoring of antineoplastic treatment success,with identification of potentially developed resistance or therapeutic targets during the course of treatment.It may also assist in early change of chemotherapy in metastatic gastrointestinal malignancies prior to imaging findings of relapse.Nevertheless,clinical utility is dependent on the tumor’s entity and burden.
文摘For many years tissue biopsy has been the primary procedure to establish cancer diagnosis and determine further treatment and prognosis.However,this method has multiple drawbacks,including,to mention some,being an invasive procedure carrying significant risk for fragile patients and allowing only for a“snapshot”of the tumor biology in time.The process of liquid biopsy allows for a minimally invasive procedure that provides molecular information about underlying cancer by analyzing circulating tumor DNA(ctDNA)via next-generation sequencing technology and circulating tumor cells.This paper focuses on describing the basis of ctDNA and its current utilities.
文摘BACKGROUND Patients diagnosed with non-small-cell lung cancer with activated epidermal growth factor receptor mutations are more likely to develop leptomeningeal(LM)metastasis than other types of lung cancers and have a poor prognosis.Early diagnosis and effective treatment of leptomeningeal carcinoma can improve the prognosis.CASE SUMMARY A 55-year-old female with a progressive headache and vomiting for one month was admitted to Peking University First Hospital.She was diagnosed with lung adenocarcinoma with osseous metastasis 10 months prior to admittance.epidermal growth factor receptor(EGFR)mutation was detected by genomic examination,so she was first treated with gefitinib for 10 months before acquiring resistance.Cell-free cerebrospinal fluid(CSF)circulating tumor DNA detection by next-generation sequencing was conducted and indicated the EGFR-Thr790Met mutation,while biopsy and cytology from the patient’s CSF and the first enhanced cranial magnetic resonance imaging(MRI)showed no positive findings.A month later,the enhanced MRI showed linear leptomeningeal enhancement,and the cytology and biochemical examination in CSF remained negative.Therefore,osimertinib(80 mg/d)was initiated as a second-line treatment,resulting in a good response within a month.CONCLUSION This report suggests clinical benefit of osimertinib in LM patients with positive detection of the EGFR-Thr790Met mutation in CSF and proposes that the positive findings of CSF circulating tumor DNA as a liquid biopsy technology based on the detection of cancer-associated gene mutations may appear earlier than the imaging and CSF findings and may thus be helpful for therapy.Moreover,the routine screening of chest CT with the novel coronavirus may provide unexpected benefits。
文摘Objectives: Circulating tumor DNA (ctDNA) is shown to provide the real-time genomic information of metastatic breast cancer. This study elucidates the clinico-pathological significance of ctDNA in early-stage breast cancer using the PIK3CA mutation as an indicator. Materials and Methods: Twenty-seven primary breast cancers without metastasis were surgically resected and pathologically diagnosed at the University of Tokyo Hospital, Japan. Genomic DNA of primary tumor was extracted from formalin-fixed and paraffin-embedded specimens. ctDNA was extracted from fresh-frozen plasma from patients. The PIK3CA mutations at E542K, E545K and H1047R were examined by Sanger sequencing or droplet digital PCR in 27 tumors and pre- and post-surgery plasma. Results: The PIK3CA mutations were detected in 13 (48%) of 27 primary tumors. These mutations did not significantly correlate with specific clinico-pathological characteristics of tumors. When ctDNA was examined, 4 (33%) of 12 cases carrying the mutated PIK3CA showed the identical mutation in pre-surgery plasma and 2 (50%) of them showed the identical mutations in post-surgery plasma. Interestingly, in these 2 cases in pathological stages IIIA and IA, fractional abundance of the mutated PIK3CA alleles to the total alleles in pre-surgery ctDNA was around 1% or more and was higher than that of the other two cases without PIK3CA mutations in post-surgery ctDNA. Conclusions: The PIK3CA mutation in ctDNA is detectable even in a subset of early-stage breast cancer. Furthermore, fractional abundance of the mutated PIK3CA in pre-surgery ctDNA could provide a possible predictive indicator for tumor burden and for choosing the appropriate adjuvant treatment of breast cancer.
基金Supported by the Natural Science Foundation of Chongqing,No. cstc2018jcyj AX0781the Major Project of Chongqing Health Committee,No. cstc2016 shmszx130033031+1 种基金the National Natural Science Foundation of China,No. 81302316the Chongqing technological innovation and application development-Major theme projects,No. cstc2019jscxfxydx0008
文摘BACKGROUND The poly(ADP-ribose)polymerase(PARP)inhibitor olaparib has displayed superior clinical effect in metastatic castration-resistant prostate cancer(mCRPC)patients with the homologous recombination repair(HRR)genes mutations.However,when a patient’s tumor tissue volume is insufficient for genomic profiling of HRR gene mutations,circulating tumor DNA(ctDNA)may be useful in helping to determine and monitor the efficacy of olaparib,as well as in abiraterone-combination treatment,and for understanding any resistance mechanism related to such mutations.CASE SUMMARY A 61-year-old man who was diagnosed with metastatic prostate adenocarcinoma was initially hormone sensitivity,showing high Gleason score(5+5=10)and absolute positive rate(14/14 biopsied specimens).Following failure of several standard therapies,the patient progressed to mCRPC.Surprisingly,the patient showed good response to olaparib-abiraterone-prednisone combination treatment(an androgen-deprivation therapy,provided as the‘final choice’in China).Serum total prostate-specific antigen(TPSA)level reduced and symptoms remitted for 4 months.However,thereafter,serum TPSA levels began slowly increasing,indicating development of olaparib resistance.Subsequent comprehensive genomic profiling of ctDNA, screening 508 cancer-related genes by next-generation sequencing,identified 10 somatic variants as well as 3 copy number alterations. Two identified reversemissense mutations in partner and localizer of BRCA2 (PALB2) may have recovered the readingframe, restoring function of the primary germline PALB2 mutation and causing resistance to thePARP inhibitor olaparib.CONCLUSIONReverse mutations in PALB2, discovered via genomic profiling of ctDNA, may represent apotential resistance mechanism against olaparib in mCRPC.
文摘Objective:This study aimed to investigate the relationship between circulating tumor DNA and epithelial ovarian cancer.Methods:Twenty-seven cases with epithelial ovarian cancer in changle people's hospital in shandong province were collected.Blood samples before operation were collected to detect circulating tumor DNA.Results:There are 22 ctDNA positive cases,with a proportion of 81.5%(22/27).Proportion of ctDNA positive patients before operation in the early and advanced stage was 60%and 94.1%respectively,with a statistically significant difference(P<0.05).The difference of proportion of ctDNA positive patients before operation in the subgroup analysis based on clinical stage,histological grading,pathological types,and tumor size was statistically significant(P<0.05).Conclusion:CtDNA is a promising tumor marker associated with epithelial ovarian cancer.
