AIM:To explore the methylation status of MSH6 in retinoblastoma(RB)and its impact on clinicopathological features and diagnosis.METHODS:Differentially expressed genes were identified through bioinformatics screening o...AIM:To explore the methylation status of MSH6 in retinoblastoma(RB)and its impact on clinicopathological features and diagnosis.METHODS:Differentially expressed genes were identified through bioinformatics screening of the GSE24673 and GSE125903 datasets,combined with GeneCards database analysis.A total of 102 RB patients and 62 traumaenucleated controls between January 2018 and December 2023 were enrolled,with their clinicopathological data and retinal tissues collected.The mRNA and methylation levels of MSH6 in retinal tissues were detected using real-time quantitative polymerase chain reaction(PCR)and methylation-specific PCR.Western blot analysis was conducted in one pair of RB and control tissues for preliminary protein-level validation of MSH6 expression.Based on the methylation status of MSH6,RB patients were categorized into two groups:low-methylation and highmethylation.Both univariate and multivariate analyses were conducted to identify independent factors influencing the methylation levels using clinicopathological data.Receiver operating characteristic(ROC)curves were applied to evaluate the diagnostic potential of MSH6 methylation in RB.RESULTS:Bioinformatics analysis of public datasets revealed that MSH6 expression was downregulated across multiple cancers,RB.Consistently,in clinical RB tissues,MSH6 mRNA expression was significantly lower than that in control retinal tissues,whereas the promoter methylation level of MSH6 was markedly higher(both P<0.001),indicating that promoter hypermethylation may contribute to transcriptional silencing of MSH6 in RB.Patients with higher MSH6 methylation levels showed more advanced pathological classification and a higher frequency of metastasis.Multivariate logistic regression confirmed that metastatic status(P=0.008,OR=3.51)and pathological classification(P=0.005,OR=3.7)were independent factors associated with MSH6 methylation.Receiver operating characteristic(ROC)analysis demonstrated that MSH6 methylation could effectively distinguish RB tissues from non-tumorous controls(AUC=0.847,sensitivity=78.43%,specificity=80.65%),suggesting that MSH6 hypermethylation may serve as a potential diagnostic biomarker for RB.CONCLUSION:The methylation level of the MSH6 gene may be a key factor in RB pathogenesis.The methylation status of the MSH6 gene is closely associated with clinicopathological features and shows diagnostic potential.展开更多
AIM: To investigate the germline mutations of MSH6 gene in probands of Chinese hereditary non-polyposis colorectal cancer (HNPCC) families fulfilling different clinical criteria. METHODS: Germline mutations of MSH6 ge...AIM: To investigate the germline mutations of MSH6 gene in probands of Chinese hereditary non-polyposis colorectal cancer (HNPCC) families fulfilling different clinical criteria. METHODS: Germline mutations of MSH6 gene were detected by PCR-based DNA sequencing in 39 unrelated HNPCC probands fulfilling different clinical criteria in which MSH2 and MLH1 mutations were excluded. To further investigate the pathological effects of detected missense mutations, we analyzed the above related MSH6 exons using PCR-based sequencing in 137 healthy persons with no family history. The clinicopathological features were collected from the Archive Library of Cancer Hospital, Fudan University and analyzed. RESULTS: Four germline missense mutations distributed in the 4th, 6th and 9th exons were observed. Of them, three were not found in international HNPCC databases and did not occur in 137 healthy controls, indicating that they were novel missense mutations. The remaining mutation which is consistent with the case H14 at c.3488A>T of exon 6 of MSH6 gene was also found in the controls, the rate was approximately 3.65% (5/137) and the type of mutation was not found in the international HNPCC mutational and SNP databases, suggesting that this missense mutation was a new SNP unreported up to date. CONCLUSION: Three novel missense mutations and a new SNP observed in the probands of Chinese HNPCC families, may play an important role in the development of HNPCC.展开更多
文摘AIM:To explore the methylation status of MSH6 in retinoblastoma(RB)and its impact on clinicopathological features and diagnosis.METHODS:Differentially expressed genes were identified through bioinformatics screening of the GSE24673 and GSE125903 datasets,combined with GeneCards database analysis.A total of 102 RB patients and 62 traumaenucleated controls between January 2018 and December 2023 were enrolled,with their clinicopathological data and retinal tissues collected.The mRNA and methylation levels of MSH6 in retinal tissues were detected using real-time quantitative polymerase chain reaction(PCR)and methylation-specific PCR.Western blot analysis was conducted in one pair of RB and control tissues for preliminary protein-level validation of MSH6 expression.Based on the methylation status of MSH6,RB patients were categorized into two groups:low-methylation and highmethylation.Both univariate and multivariate analyses were conducted to identify independent factors influencing the methylation levels using clinicopathological data.Receiver operating characteristic(ROC)curves were applied to evaluate the diagnostic potential of MSH6 methylation in RB.RESULTS:Bioinformatics analysis of public datasets revealed that MSH6 expression was downregulated across multiple cancers,RB.Consistently,in clinical RB tissues,MSH6 mRNA expression was significantly lower than that in control retinal tissues,whereas the promoter methylation level of MSH6 was markedly higher(both P<0.001),indicating that promoter hypermethylation may contribute to transcriptional silencing of MSH6 in RB.Patients with higher MSH6 methylation levels showed more advanced pathological classification and a higher frequency of metastasis.Multivariate logistic regression confirmed that metastatic status(P=0.008,OR=3.51)and pathological classification(P=0.005,OR=3.7)were independent factors associated with MSH6 methylation.Receiver operating characteristic(ROC)analysis demonstrated that MSH6 methylation could effectively distinguish RB tissues from non-tumorous controls(AUC=0.847,sensitivity=78.43%,specificity=80.65%),suggesting that MSH6 hypermethylation may serve as a potential diagnostic biomarker for RB.CONCLUSION:The methylation level of the MSH6 gene may be a key factor in RB pathogenesis.The methylation status of the MSH6 gene is closely associated with clinicopathological features and shows diagnostic potential.
基金Supported by Shanghai Medical Development Fund for Major Projects, No. 05Ⅲ004 and Shanghai Pu Jiang Projects for Talented-Men, 06PJ14019
文摘AIM: To investigate the germline mutations of MSH6 gene in probands of Chinese hereditary non-polyposis colorectal cancer (HNPCC) families fulfilling different clinical criteria. METHODS: Germline mutations of MSH6 gene were detected by PCR-based DNA sequencing in 39 unrelated HNPCC probands fulfilling different clinical criteria in which MSH2 and MLH1 mutations were excluded. To further investigate the pathological effects of detected missense mutations, we analyzed the above related MSH6 exons using PCR-based sequencing in 137 healthy persons with no family history. The clinicopathological features were collected from the Archive Library of Cancer Hospital, Fudan University and analyzed. RESULTS: Four germline missense mutations distributed in the 4th, 6th and 9th exons were observed. Of them, three were not found in international HNPCC databases and did not occur in 137 healthy controls, indicating that they were novel missense mutations. The remaining mutation which is consistent with the case H14 at c.3488A>T of exon 6 of MSH6 gene was also found in the controls, the rate was approximately 3.65% (5/137) and the type of mutation was not found in the international HNPCC mutational and SNP databases, suggesting that this missense mutation was a new SNP unreported up to date. CONCLUSION: Three novel missense mutations and a new SNP observed in the probands of Chinese HNPCC families, may play an important role in the development of HNPCC.