Objective:To probe into the relationships between PTEN gene expression,the promoter methylation and gastric cancer and its clinical pathological specific features.Methods:We analyzed the PTEN gene promoter methylation...Objective:To probe into the relationships between PTEN gene expression,the promoter methylation and gastric cancer and its clinical pathological specific features.Methods:We analyzed the PTEN gene promoter methylation and mRNA expression status in gastric cancer tissues and its adjacent normal tissues by methylation specific PCR(MSP) and reverse transcription-polymerase chain reaction(RT-PCR) techniques.Results:PTEN promoters in 48.2%(27/56) gastric cancer tissues and 3.6(2/56) adjacent normal tissues were methylated and the PTEN promoter methylation rate in carcinoma tissues was obviously higher(P < 0.05).Of the 2 cases where the adjacent gastric tissues were methylated,the gastric cancer tissues were both methylated.Of the 29 gastric cancers with lymph node metastasis,19 had their PTEN gene promoters methylated and the PTEN gene promoter methylation in cases with lymph node metastasis was obviously higher than that without lymph node metastasis(P < 0.05).RT-PCR result showed that no expression of PTEN mRNA existed in any of the methylated gastric cancer tissues.Conclusion:The expression loss of PTEN gene mRNA in gastric cancers is related to their promoter methylation and might be one of the reasons for the generation,development and metastasis of gastric cancers.展开更多
AIM： To investigate the promoter region methylation status of retinoblastoma protein-interacting zinc finger gene 1 （RIZ1） in the human esophageal squamous cell carcinoma （ESCC） cell lines and tissues and verify ...AIM： To investigate the promoter region methylation status of retinoblastoma protein-interacting zinc finger gene 1 （RIZ1） in the human esophageal squamous cell carcinoma （ESCC） cell lines and tissues and verify the relationship between methylation of RIZ1 and oncogen- esis, tumor progression and metastasis etc of ESCC. METHODS： Methylation-specific polymerase chain reac- tion （MSP） was used to investigate the promoter region methylation status of RIZ1 in 6 ESCC cell lines. One cell line where RIZ1 promoter region methylation was de- tected was selected for the next study, where the cell line was treated with 5-aza-CdR. Real-time polymerase chain reaction was used to investigate its influence on the transcription of RIZ1. Experiments using frozenpathological specimens from 47 ESCC patients were performed using the same MSP methodology. RESULTS： Promoter methylation of RIZ1 gene was detected in TEl3, CaEs17 and EC109 cell lines and the cell line TEl3 was chosen for further study. The expression of RIZl mRNA in TE-13 was up-regulated after treatment with 5-aza-CdR. The rate of methyla- tion in carcinomas tissues was significantly higher than those in matched neighboring normal and distal ending normal tissue, and the deviation of data was statisti- cally significant （2,2 = 24.136, P 〈 0.01）. Analysis of the gender, age familial history, tumour deviation, tumour saturation, lymph gland displacement and clinical stag- ing of 47 samples from ESCC patients showed that the fluctuation of data was not statistically significant. CONCLUSION： Promoter methylation may play an im- portant role in the epigenetic silencing of RIZ1 gene expression in human ESCC. RIZ1 is considered to be a potential tumor suppressor gene and may be a biologi- cal parameter for testing early stage human ESCC.展开更多
Esophageal squamous cell carcinoma(ESCC) is a prevalent and fatal cancer in China and other Asian countries.Epigenetic silencing of key tumor suppressor genes(TSGs) is critical to ESCC initiation and progression.Recen...Esophageal squamous cell carcinoma(ESCC) is a prevalent and fatal cancer in China and other Asian countries.Epigenetic silencing of key tumor suppressor genes(TSGs) is critical to ESCC initiation and progression.Recently,many novel TSGs silenced by promoter methylation have been identified in ESCC,and these genes further serve as potential tumor markers for high-risk group stratification,early detection,and prognosis prediction.This review summarizes recent discoveries on aberrant promoter methylation of TSGs in ESCC,providing better understanding of the role of disrupted epigenetic regulation in tumorigenesis and insight into diagnostic and prognostic biomarkers for this malignancy.展开更多
基金a grant from the National Natural Science Foundation of China(No.30300154)
文摘Objective:To probe into the relationships between PTEN gene expression,the promoter methylation and gastric cancer and its clinical pathological specific features.Methods:We analyzed the PTEN gene promoter methylation and mRNA expression status in gastric cancer tissues and its adjacent normal tissues by methylation specific PCR(MSP) and reverse transcription-polymerase chain reaction(RT-PCR) techniques.Results:PTEN promoters in 48.2%(27/56) gastric cancer tissues and 3.6(2/56) adjacent normal tissues were methylated and the PTEN promoter methylation rate in carcinoma tissues was obviously higher(P < 0.05).Of the 2 cases where the adjacent gastric tissues were methylated,the gastric cancer tissues were both methylated.Of the 29 gastric cancers with lymph node metastasis,19 had their PTEN gene promoters methylated and the PTEN gene promoter methylation in cases with lymph node metastasis was obviously higher than that without lymph node metastasis(P < 0.05).RT-PCR result showed that no expression of PTEN mRNA existed in any of the methylated gastric cancer tissues.Conclusion:The expression loss of PTEN gene mRNA in gastric cancers is related to their promoter methylation and might be one of the reasons for the generation,development and metastasis of gastric cancers.
基金Supported by Grant-in-aid from Specialized Research Fund for the Doctoral Program of Higher Education,No. 20091202110009Grant-in-aid from Natural Science Foundation of Tianjin,No. 10JCYBJC11300
文摘AIM： To investigate the promoter region methylation status of retinoblastoma protein-interacting zinc finger gene 1 （RIZ1） in the human esophageal squamous cell carcinoma （ESCC） cell lines and tissues and verify the relationship between methylation of RIZ1 and oncogen- esis, tumor progression and metastasis etc of ESCC. METHODS： Methylation-specific polymerase chain reac- tion （MSP） was used to investigate the promoter region methylation status of RIZ1 in 6 ESCC cell lines. One cell line where RIZ1 promoter region methylation was de- tected was selected for the next study, where the cell line was treated with 5-aza-CdR. Real-time polymerase chain reaction was used to investigate its influence on the transcription of RIZ1. Experiments using frozenpathological specimens from 47 ESCC patients were performed using the same MSP methodology. RESULTS： Promoter methylation of RIZ1 gene was detected in TEl3, CaEs17 and EC109 cell lines and the cell line TEl3 was chosen for further study. The expression of RIZl mRNA in TE-13 was up-regulated after treatment with 5-aza-CdR. The rate of methyla- tion in carcinomas tissues was significantly higher than those in matched neighboring normal and distal ending normal tissue, and the deviation of data was statisti- cally significant （2,2 = 24.136, P 〈 0.01）. Analysis of the gender, age familial history, tumour deviation, tumour saturation, lymph gland displacement and clinical stag- ing of 47 samples from ESCC patients showed that the fluctuation of data was not statistically significant. CONCLUSION： Promoter methylation may play an im- portant role in the epigenetic silencing of RIZ1 gene expression in human ESCC. RIZ1 is considered to be a potential tumor suppressor gene and may be a biologi- cal parameter for testing early stage human ESCC.
基金supported by NSFC Joint Research Fund for Hong Kong and Macao Young Scholars(No.30928012)National Natural Science Foundation of China(No.81071634,81172582,and 30801344)Shenzhen Science Fund for Distinguished Young Scholars(No.JC201005270328A)
文摘Esophageal squamous cell carcinoma(ESCC) is a prevalent and fatal cancer in China and other Asian countries.Epigenetic silencing of key tumor suppressor genes(TSGs) is critical to ESCC initiation and progression.Recently,many novel TSGs silenced by promoter methylation have been identified in ESCC,and these genes further serve as potential tumor markers for high-risk group stratification,early detection,and prognosis prediction.This review summarizes recent discoveries on aberrant promoter methylation of TSGs in ESCC,providing better understanding of the role of disrupted epigenetic regulation in tumorigenesis and insight into diagnostic and prognostic biomarkers for this malignancy.
