Objective To investigate the role of TNF receptor-associated factor 2 (TRAF-2) and TRAF6 in CD40-induced nuclear factor-κB (NF-κB) signaling pathway and whether CD40 signaling requires TRAF2. Methods Human B cell li...Objective To investigate the role of TNF receptor-associated factor 2 (TRAF-2) and TRAF6 in CD40-induced nuclear factor-κB (NF-κB) signaling pathway and whether CD40 signaling requires TRAF2. Methods Human B cell lines were transfected with plasmids expressing wild type TRAF2 or dominant negative TRAF2,TRAF2-shRNA,or TRAF6-shRNA. The activation of NF-κB was detected by Western blot,kinase assay,transfactor enzyme-linked immunosorbent assay (ELISA),and fluorescence resonance energy transfer (FRET). Analysis of the role of TRAF-2 and TRAF-6 in CD40-mediated NF-κB activity was examined following stimulation with recombinant CD154. Results TRAF2 induced activity of IκB-kinases (IKKα,IKKi/ε),phosphorylation of IκBα,as well as nuclear translocation and phosphorylation of p65/RelA. In contrast,TRAF6 strongly induced NF-κB activation and nuclear translocation of p65 as well as p50 and c-Rel. Engagement of CD154-induced nuclear translocation of p65 was inhibited by a TRAF6-shRNA,but conversely was enhanced by a TRAF2-shRNA. Examination of direct interactions between CD40 and TRAFs by FRET documented that both TRAF2 and TRAF6 directly interacted with CD40. However,the two TRAFs competed for CD40 binding. Conclusions These results indicate that TRAF2 can signal in human B cells,but it is not essential for CD40-mediated NF-κB activation. Moreover,TRAF2 can compete with TRAF6 for CD40 binding,and thereby limit the capacity of CD40 engagement to induce NF-κB activation.展开更多
AIM: To clarify human papillomavirus (HPV) involvement in carcinogenesis of the upper digestive tract of virological and pathological analyses. METHODS: The present study examined the presence of HPV in squamous cell ...AIM: To clarify human papillomavirus (HPV) involvement in carcinogenesis of the upper digestive tract of virological and pathological analyses. METHODS: The present study examined the presence of HPV in squamous cell carcinomas of the oral cavity (n = 71), and esophagus (n = 166) collected from Japan, Pakistan and Colombia, with different HPV exposure risk and genetic backgrounds. The viral load and physical status of HPV16 and HPV16-E6 variants were examined. Comparison of p53 and p16INK4a expression in HPV-positive and HPV-negative cases was also made. RESULTS: HPV16 was found in 39 (55%) oral carcinomas (OCs) and 24 (14%) esophageal carcinomas (ECs). This site-specific difference in HPV detection between OCs and ECs was statistically significant (P < 0.001). There was a significant difference in the geographical distribution of HPV16-E6 variants. Multiple infections of different HPV types were found in 13 ECs, but multiple infections were not found in OCs. This difference was statistically significant (P = 0.001). The geometric means (95% confidence interval) of HPV16 viral load in OCs and ECs were 0.06 (0.02-0.18) and 0.12 (0.05-0.27) copies per cell, respectively. The expression of p16INK4a proteins was increased by the presence of HPV in ECs (53% and 33% in HPV-positive and-negative ECs, respectively; P = 0.036), and the high-risk type of the HPV genome was not detected in surrounding normal esophageal mucosa of HPV-positive ECs. CONCLUSION: Based on our results, we cannot deny the possibility of HPV16 involvement in the carcinogenesis of the esophagus.展开更多
High grade anal intraepithelial neoplasia due to human papilloma viral(HPV)infections is a precursor lesion for squamous cell carcinoma especially in high risk populations.Frequent examination and anal biopsies remain...High grade anal intraepithelial neoplasia due to human papilloma viral(HPV)infections is a precursor lesion for squamous cell carcinoma especially in high risk populations.Frequent examination and anal biopsies remain unpopular with patients;moreover they are also risk factors for chronic pain,scarring and sphincter injury.There is lack of uniform,surveillance methods and guidelines for anal HPV specifically the intervals between exam and biopsies.The aim of this editorial is to discuss the intervals for surveillance exam and biopsy,based on specific HPV related biomarkers?Currently there are no published randomized controlled trials documenting the effectiveness of anal screening and surveillance programs to reduce the incidence,morbidity and mortality of anal cancers.In contrast,the currently approved screening and surveillance methods available for HPV related cervical cancer includes cytology,HPV DNA test,P16 or combined P16/Ki-67 index and HPV E/6 and E/7 mRNA test.There are very few studies performed to determine the efficacy of these tests in HPV related anal precancerous lesions.The relevance of these biomarkers is discussed in this editorial.Longitudinal prospective research is needed to confirm the effectiveness of these molecular biomarkers that include high risk HPV serotyping,P16 immuno-histiochemistry and E6/E7 mRNA profiling on biopsies to elucidate and establish surveillance guidelines.展开更多
In order to detect molecular markers for the epidermal growth factor inhibitor 4-(3-chloro-benzyl)- 6,7-dimethoxy-quinazoline (tyrphostin), we investigated the kinetics of p120-catenin and periplakin in the human bucc...In order to detect molecular markers for the epidermal growth factor inhibitor 4-(3-chloro-benzyl)- 6,7-dimethoxy-quinazoline (tyrphostin), we investigated the kinetics of p120-catenin and periplakin in the human buccal mucosa squamous cancer cell line BICR 10 treated with 3 nM tyrphostin. Growth of BICR 10 cells was inhibited by treatment with tyrphostin. Although changes were not observed in the expression of EGFR and p120-catenin, expression of Akt, Src and periplakin in BICR 10 treated with 3 nM tyrphostin tended to decrease. In addition, phosphorylation of EGFR, Akt and Src was inhibited by treatment with tyrphostin. On immunocytochemical staining, immunoreactions with phosphorylated EGFR, phosphorylated Akt and phosphorylated p120-catenin were weak in BICR 10 treated with tyrphostin. There was a slight immunocy to chemical reaction to periplakin in BICR 10 cells induced by tyrphostin. In conclusion, the decrease in phosphorylation in EGFR and p120-catenin by tyrphostin, following the decrease in Src or Akt phosphorylation, may inhibit expression of several growth factors associated with the proliferation and migration of cancer cells.展开更多
In the present study, the interaction of human p100 protein with signal transducer and activator of transcription-6 (STAT-6) was investigated. It was proved that the staphylococcal nuclease (SN)-like and tudor (TD) do...In the present study, the interaction of human p100 protein with signal transducer and activator of transcription-6 (STAT-6) was investigated. It was proved that the staphylococcal nuclease (SN)-like and tudor (TD) domains containing in p100 protein acting as a adaptor to recruit STAT-6 to the basal transcription machinery, enhanced the STAT-6 mediated transcription activity. The interaction between STAT-6 and the p100 protein was mediated by the full-length of the SN-like domain, whereas individual fragments of SN-like domain showed no binding activity to STAT-6. In line with these results, the SN-like domain was directly engaged in the enhancement of STAT-6 mediated activation of gene transcription in vivo. Yet the TD domain had no ability to increase the transcription activation, but it was still required for the sufficient activation of transcription.展开更多
Objective To study the modulatory effect of distillate of Ocimum sanctum （traditionally known as Tulsi） leaf extract （DTLE） on genotoxicants. Methods In the present investigation, we studied the antigenotoxic and ...Objective To study the modulatory effect of distillate of Ocimum sanctum （traditionally known as Tulsi） leaf extract （DTLE） on genotoxicants. Methods In the present investigation, we studied the antigenotoxic and anticlastogenic effect of distillate of Tulsi leaf extract on （i） human polymorphonuclear leukocytes by evaluating the DNA strand break without metabolic activation against mitomycin C （MMC） and hexavalent chromium （Cr^＋6） and （ii） human peripheral lymphocytes （in vitro） with or without metabolic activation against mitomycin C （MMC）, hexavalent chromium （Cr^＋6） and B[a]P by evaluating chromosomal aberration （CA） and micronucleus assay （MN）. Three different doses of DTLE, 50 μL/mL, 100 μL/mL, and 200 μL/mL were selected on the basis of cytotoxicity assay and used for studying DNA strand break, chromosomal aberration and micronucleus emergence. The following positive controls were used for inducing genotoxicity and clastogenicity MMC （0.29 μmol/L） for DNA strand break, chromosomal aberration and 0.51 μmol/L for micronucleus assay; Potassium dichromate （Cr^＋6） 600 μmol/L for DNA strand break and 5 μmol/L for chromosomal aberration and micronucleus assay; Benzo[a]pyrene （30 μmol/L） for chromosomal aberration and 40 μmol/L for micronucleus assay. The active ingredients present in the distillate of Tulsi leaf extract were identified by HPLC and LC-MS. Results Mitomycin C （MMC） and hexavalent chromium （Cr^＋6） induced statistically significant DNA strand break of respectively 69% and 71% （P〈0.001） as revealed by fluorometric analysis of DNA unwinding. Furthermore, the damage could be protected with DTLE （50 μL/mL, 100 μL/mL, and 200 μL/mL） on simultaneous treatment. Chromosomal aberration and micronucleus formation induced by MMC, Cr^＋6 and B[a]P were significantly protected （P〈0.001） by DTLE with and without metabolic activation. Conclusion Distillate of Tulsi leaf extract possesses antioxidants contributed mainly by eugenol, luteolin and apigenin as identified by LC-MS. These active ingredients may have the protective effect against genotoxicants.展开更多
Oxidation and reduction of some amino acids are one of the molecular mechanisms for regulating the function of proteins. The oxidation of methionine (Met) to methionine sulfoxide (Met(O)) results in decreasing or loss...Oxidation and reduction of some amino acids are one of the molecular mechanisms for regulating the function of proteins. The oxidation of methionine (Met) to methionine sulfoxide (Met(O)) results in decreasing or loss of the biological activity of related proteins. It was found that peptide methionine sulfoxide reductase (msrA) can reduce Met(O) to Met and therefore restored the biological function of the oxidized proteins. To reveal the methionine oxidation-reduction mechanism in human body, in this study, the cDNA sequence of bovine msrA was used as an information-probe to screen the human EST database. Based on a contig assembled from homologous ESTs, a 1 256-bp human MSRA cDNA was cloned from several human cDNA libraries. The cDNA contains an open reading frame (ORF) of 705 bp in length, which encodes 235 amino acid residues. Homology comparison revealed that human MSRA shares 88% and 61% identities with bovine and Escherichia coli msrA protein respectively. Expression pattern analysis revealed a展开更多
Using a combination of hybridization of PAC to a cDNA library and RACE technique, we isolated a novel cDNA, designated as C17orf25 (Chromosome 17 open rea(ling frame 25, previously named it HC71A), from the deletion r...Using a combination of hybridization of PAC to a cDNA library and RACE technique, we isolated a novel cDNA, designated as C17orf25 (Chromosome 17 open rea(ling frame 25, previously named it HC71A), from the deletion region on chromosome 17p13.3. The cDNA encodes a protein of 313 amino acids with a calculated molecular mass of 34.8 kDa. C17orf25 is divided into 10 exons and 9 introns, spanning 23 kb of genomic DNA. Northern blot analysis showed that the mRNA expression of C17orf25 was decreased in hepatocellular carcinoma samples as compared to adjacent noncancerous liver tissues from the same patients. The transfection of C17or25 into the hepatocellular carcinoma cell SMMC7721 and overexpression could inhibit the cell growth. The above results indicate that C17orf25 is a novel human gene, and the cloning and preliminary characterization of C17orf25 is a prerequisite for further functional analysis of this novel gene in human hepatocellular carcinoma.展开更多
Enteropathy-associated T-cell lymphoma （EATL） is a rare peripheral T-cell lymphoma classified into 2 types, with or without celiac disease, based on histology. Type 2 EATL is less commonly associated with celiac dis...Enteropathy-associated T-cell lymphoma （EATL） is a rare peripheral T-cell lymphoma classified into 2 types, with or without celiac disease, based on histology. Type 2 EATL is less commonly associated with celiac disease, in which cells are characterized by being monomorphic and small- to medium-sized. Cells are characterized by CD8 and CD56 expression and c-MYC oncogene locus gain. We present an atypical case of type 2 EATL in the jejunum, with human T-lymphotropic virus-1 that was CD4- CDS＋ CD56- CD30- CD25- TIA-I＋ and granzyme B＋ on immunohistological staining. It also displayed translocation of chromosome 8p24 （c-MYC）, as de- termined by fluorescent/n situ hybridization. Mucosalspreading and intraepithelial invasion by lymphoma with villous atrophy were detected adjacent to the mucosal layer. The lymphoma may be derived from in- traepithelial CD8＋ T cells, similar to celiac disease.展开更多
基金Supported by Key Projects of the National Science & Technology Pillar Program in the Eleventh Five-year Plan Period (2008-BAI59B02)
文摘Objective To investigate the role of TNF receptor-associated factor 2 (TRAF-2) and TRAF6 in CD40-induced nuclear factor-κB (NF-κB) signaling pathway and whether CD40 signaling requires TRAF2. Methods Human B cell lines were transfected with plasmids expressing wild type TRAF2 or dominant negative TRAF2,TRAF2-shRNA,or TRAF6-shRNA. The activation of NF-κB was detected by Western blot,kinase assay,transfactor enzyme-linked immunosorbent assay (ELISA),and fluorescence resonance energy transfer (FRET). Analysis of the role of TRAF-2 and TRAF-6 in CD40-mediated NF-κB activity was examined following stimulation with recombinant CD154. Results TRAF2 induced activity of IκB-kinases (IKKα,IKKi/ε),phosphorylation of IκBα,as well as nuclear translocation and phosphorylation of p65/RelA. In contrast,TRAF6 strongly induced NF-κB activation and nuclear translocation of p65 as well as p50 and c-Rel. Engagement of CD154-induced nuclear translocation of p65 was inhibited by a TRAF6-shRNA,but conversely was enhanced by a TRAF2-shRNA. Examination of direct interactions between CD40 and TRAFs by FRET documented that both TRAF2 and TRAF6 directly interacted with CD40. However,the two TRAFs competed for CD40 binding. Conclusions These results indicate that TRAF2 can signal in human B cells,but it is not essential for CD40-mediated NF-κB activation. Moreover,TRAF2 can compete with TRAF6 for CD40 binding,and thereby limit the capacity of CD40 engagement to induce NF-κB activation.
基金Suppreted by Grants-in-Aid for Scientific Research on Priority Areas (17015037) of the Ministry of Education, Culture, Sports,Science and Technology, Japan
文摘AIM: To clarify human papillomavirus (HPV) involvement in carcinogenesis of the upper digestive tract of virological and pathological analyses. METHODS: The present study examined the presence of HPV in squamous cell carcinomas of the oral cavity (n = 71), and esophagus (n = 166) collected from Japan, Pakistan and Colombia, with different HPV exposure risk and genetic backgrounds. The viral load and physical status of HPV16 and HPV16-E6 variants were examined. Comparison of p53 and p16INK4a expression in HPV-positive and HPV-negative cases was also made. RESULTS: HPV16 was found in 39 (55%) oral carcinomas (OCs) and 24 (14%) esophageal carcinomas (ECs). This site-specific difference in HPV detection between OCs and ECs was statistically significant (P < 0.001). There was a significant difference in the geographical distribution of HPV16-E6 variants. Multiple infections of different HPV types were found in 13 ECs, but multiple infections were not found in OCs. This difference was statistically significant (P = 0.001). The geometric means (95% confidence interval) of HPV16 viral load in OCs and ECs were 0.06 (0.02-0.18) and 0.12 (0.05-0.27) copies per cell, respectively. The expression of p16INK4a proteins was increased by the presence of HPV in ECs (53% and 33% in HPV-positive and-negative ECs, respectively; P = 0.036), and the high-risk type of the HPV genome was not detected in surrounding normal esophageal mucosa of HPV-positive ECs. CONCLUSION: Based on our results, we cannot deny the possibility of HPV16 involvement in the carcinogenesis of the esophagus.
文摘High grade anal intraepithelial neoplasia due to human papilloma viral(HPV)infections is a precursor lesion for squamous cell carcinoma especially in high risk populations.Frequent examination and anal biopsies remain unpopular with patients;moreover they are also risk factors for chronic pain,scarring and sphincter injury.There is lack of uniform,surveillance methods and guidelines for anal HPV specifically the intervals between exam and biopsies.The aim of this editorial is to discuss the intervals for surveillance exam and biopsy,based on specific HPV related biomarkers?Currently there are no published randomized controlled trials documenting the effectiveness of anal screening and surveillance programs to reduce the incidence,morbidity and mortality of anal cancers.In contrast,the currently approved screening and surveillance methods available for HPV related cervical cancer includes cytology,HPV DNA test,P16 or combined P16/Ki-67 index and HPV E/6 and E/7 mRNA test.There are very few studies performed to determine the efficacy of these tests in HPV related anal precancerous lesions.The relevance of these biomarkers is discussed in this editorial.Longitudinal prospective research is needed to confirm the effectiveness of these molecular biomarkers that include high risk HPV serotyping,P16 immuno-histiochemistry and E6/E7 mRNA profiling on biopsies to elucidate and establish surveillance guidelines.
文摘In order to detect molecular markers for the epidermal growth factor inhibitor 4-(3-chloro-benzyl)- 6,7-dimethoxy-quinazoline (tyrphostin), we investigated the kinetics of p120-catenin and periplakin in the human buccal mucosa squamous cancer cell line BICR 10 treated with 3 nM tyrphostin. Growth of BICR 10 cells was inhibited by treatment with tyrphostin. Although changes were not observed in the expression of EGFR and p120-catenin, expression of Akt, Src and periplakin in BICR 10 treated with 3 nM tyrphostin tended to decrease. In addition, phosphorylation of EGFR, Akt and Src was inhibited by treatment with tyrphostin. On immunocytochemical staining, immunoreactions with phosphorylated EGFR, phosphorylated Akt and phosphorylated p120-catenin were weak in BICR 10 treated with tyrphostin. There was a slight immunocy to chemical reaction to periplakin in BICR 10 cells induced by tyrphostin. In conclusion, the decrease in phosphorylation in EGFR and p120-catenin by tyrphostin, following the decrease in Src or Akt phosphorylation, may inhibit expression of several growth factors associated with the proliferation and migration of cancer cells.
文摘In the present study, the interaction of human p100 protein with signal transducer and activator of transcription-6 (STAT-6) was investigated. It was proved that the staphylococcal nuclease (SN)-like and tudor (TD) domains containing in p100 protein acting as a adaptor to recruit STAT-6 to the basal transcription machinery, enhanced the STAT-6 mediated transcription activity. The interaction between STAT-6 and the p100 protein was mediated by the full-length of the SN-like domain, whereas individual fragments of SN-like domain showed no binding activity to STAT-6. In line with these results, the SN-like domain was directly engaged in the enhancement of STAT-6 mediated activation of gene transcription in vivo. Yet the TD domain had no ability to increase the transcription activation, but it was still required for the sufficient activation of transcription.
文摘Objective To study the modulatory effect of distillate of Ocimum sanctum （traditionally known as Tulsi） leaf extract （DTLE） on genotoxicants. Methods In the present investigation, we studied the antigenotoxic and anticlastogenic effect of distillate of Tulsi leaf extract on （i） human polymorphonuclear leukocytes by evaluating the DNA strand break without metabolic activation against mitomycin C （MMC） and hexavalent chromium （Cr^＋6） and （ii） human peripheral lymphocytes （in vitro） with or without metabolic activation against mitomycin C （MMC）, hexavalent chromium （Cr^＋6） and B[a]P by evaluating chromosomal aberration （CA） and micronucleus assay （MN）. Three different doses of DTLE, 50 μL/mL, 100 μL/mL, and 200 μL/mL were selected on the basis of cytotoxicity assay and used for studying DNA strand break, chromosomal aberration and micronucleus emergence. The following positive controls were used for inducing genotoxicity and clastogenicity MMC （0.29 μmol/L） for DNA strand break, chromosomal aberration and 0.51 μmol/L for micronucleus assay; Potassium dichromate （Cr^＋6） 600 μmol/L for DNA strand break and 5 μmol/L for chromosomal aberration and micronucleus assay; Benzo[a]pyrene （30 μmol/L） for chromosomal aberration and 40 μmol/L for micronucleus assay. The active ingredients present in the distillate of Tulsi leaf extract were identified by HPLC and LC-MS. Results Mitomycin C （MMC） and hexavalent chromium （Cr^＋6） induced statistically significant DNA strand break of respectively 69% and 71% （P〈0.001） as revealed by fluorometric analysis of DNA unwinding. Furthermore, the damage could be protected with DTLE （50 μL/mL, 100 μL/mL, and 200 μL/mL） on simultaneous treatment. Chromosomal aberration and micronucleus formation induced by MMC, Cr^＋6 and B[a]P were significantly protected （P〈0.001） by DTLE with and without metabolic activation. Conclusion Distillate of Tulsi leaf extract possesses antioxidants contributed mainly by eugenol, luteolin and apigenin as identified by LC-MS. These active ingredients may have the protective effect against genotoxicants.
文摘Oxidation and reduction of some amino acids are one of the molecular mechanisms for regulating the function of proteins. The oxidation of methionine (Met) to methionine sulfoxide (Met(O)) results in decreasing or loss of the biological activity of related proteins. It was found that peptide methionine sulfoxide reductase (msrA) can reduce Met(O) to Met and therefore restored the biological function of the oxidized proteins. To reveal the methionine oxidation-reduction mechanism in human body, in this study, the cDNA sequence of bovine msrA was used as an information-probe to screen the human EST database. Based on a contig assembled from homologous ESTs, a 1 256-bp human MSRA cDNA was cloned from several human cDNA libraries. The cDNA contains an open reading frame (ORF) of 705 bp in length, which encodes 235 amino acid residues. Homology comparison revealed that human MSRA shares 88% and 61% identities with bovine and Escherichia coli msrA protein respectively. Expression pattern analysis revealed a
基金the National 863High Technology Research and Development Pro-gram of China (Zl9-02--0l-0l) to Wan DF and theProject of Ch
文摘Using a combination of hybridization of PAC to a cDNA library and RACE technique, we isolated a novel cDNA, designated as C17orf25 (Chromosome 17 open rea(ling frame 25, previously named it HC71A), from the deletion region on chromosome 17p13.3. The cDNA encodes a protein of 313 amino acids with a calculated molecular mass of 34.8 kDa. C17orf25 is divided into 10 exons and 9 introns, spanning 23 kb of genomic DNA. Northern blot analysis showed that the mRNA expression of C17orf25 was decreased in hepatocellular carcinoma samples as compared to adjacent noncancerous liver tissues from the same patients. The transfection of C17or25 into the hepatocellular carcinoma cell SMMC7721 and overexpression could inhibit the cell growth. The above results indicate that C17orf25 is a novel human gene, and the cloning and preliminary characterization of C17orf25 is a prerequisite for further functional analysis of this novel gene in human hepatocellular carcinoma.
文摘Enteropathy-associated T-cell lymphoma （EATL） is a rare peripheral T-cell lymphoma classified into 2 types, with or without celiac disease, based on histology. Type 2 EATL is less commonly associated with celiac disease, in which cells are characterized by being monomorphic and small- to medium-sized. Cells are characterized by CD8 and CD56 expression and c-MYC oncogene locus gain. We present an atypical case of type 2 EATL in the jejunum, with human T-lymphotropic virus-1 that was CD4- CDS＋ CD56- CD30- CD25- TIA-I＋ and granzyme B＋ on immunohistological staining. It also displayed translocation of chromosome 8p24 （c-MYC）, as de- termined by fluorescent/n situ hybridization. Mucosalspreading and intraepithelial invasion by lymphoma with villous atrophy were detected adjacent to the mucosal layer. The lymphoma may be derived from in- traepithelial CD8＋ T cells, similar to celiac disease.
