AIM:Most cancer cells acquire immortal capability by telornerase activation. The human telornerase reverse transcriptase gene (hTERT) is considered to be the major determinant of the enzymatic activity of human telome...AIM:Most cancer cells acquire immortal capability by telornerase activation. The human telornerase reverse transcriptase gene (hTERT) is considered to be the major determinant of the enzymatic activity of human telomerase,and the hTERTpromoter contains several c-lylyc binding sites that mediate hTERTtranscriptional activation. Few studies have examined the role of hTERTin hepatocarcinogenesis,and the relationship between c-Myc and telomerase in human hepatocellular carcinoma tissue is unknown.METHODS:We measured hTERTmRNA levels and c-Myc oncoprotein expression in 57 patients with hepatocellular carcinoma using in situhybridization and immunohistochemistry,respectively. The transcription regulation of hTERT was evaluated by transient transfection of pGL3-1375 into the human hepatocellular carcinoma cell line J5. To determine the relationship between c-Myc and the hTERTpromoter, a 1375-bp DNA fragment encompassing the promoter was placed upstream of the luciferase reporter gene and transiently transfected into the cell line. Two additional hTERT promoter constructs (-776 and -100 bp region) and an hTERT promoter-LUC construct containing 2 c-Myc mutations (pGL3-181 MycMT) were also used for luciferase assays.RESULTS:In 30 of 57 cases (52%), hTERTmRNA expression was associated with c-Myc protein expression. However,16 of 57 cases (28%) showed strong hTERTmRNA detection without c-Myc protein expression, and 11 cases (19%) showed weak hTERTmRNA expression and strong c-Myc expression.Although luciferase activity was decreased between upstream 1375 bp and 776 bp, there was no significant difference between upstream 776 bp and 100 bp. Finally, there was no significant decrease in activity after transfection of the hTERT promoter-LUC construct.CONCLUSION:The results indicate that c-Myc does not play a major role in gene regulation of the catalytic subunit of telomerase (hTERT) in human hepatocellular carcinoma.Other regulatory elements or epigenetic phenomena should be further investigated to understand hTERTgene regulation in human hepatocellular carcinoma.展开更多
AIM:It is difficult to differentiate gallstone dyspepsia and functional dyspepsia by clinical symptoms and signs. We hypothesized that gallstone dyspepsia was related to abnormal gallbladder motility. We aimed to diff...AIM:It is difficult to differentiate gallstone dyspepsia and functional dyspepsia by clinical symptoms and signs. We hypothesized that gallstone dyspepsia was related to abnormal gallbladder motility. We aimed to differentiate gallstone dyspepsia from functional dyspepsia by measuring gallbladder motility.METHODS: We measured gallbladder volume changes in response to gastric distension (saline 500mL) and fatty meal in 10normal volunteers (controls) and 62 patients with gallstones and dyspepsia before cholecystectomy. Forty cholecystectomized patients were symptom free or had improvement (group I), while the remaining 22 patients had persistent dyspepsia (group Ⅱ). Gallbladder volume change and ejection fraction were analyzed and compared among the three groups.RESULTS:In group I, there were significant decreases in gallbladder volumes 5-25 rain after gastric distension,compared to fasting volumes. Compared to normal volunteers and group Ⅱ, group I had significantly decreased gallbladder volumes 10-20min after drinking 500mL of normal saline and 10 to 50min after eating fatty meal.CONCLUSION:Our results support the hypothesis that increased gallbladder contraction after gastric distension or fatty meal may be related to dyspeptic symptoms in uncomplicated gallstone disease. These findings may be useful in differentiating functional dyspepsia from gallstone dyspepsia, patients with the latter disease may benefit from laparoscopic cholecystectomy.展开更多
文摘AIM:Most cancer cells acquire immortal capability by telornerase activation. The human telornerase reverse transcriptase gene (hTERT) is considered to be the major determinant of the enzymatic activity of human telomerase,and the hTERTpromoter contains several c-lylyc binding sites that mediate hTERTtranscriptional activation. Few studies have examined the role of hTERTin hepatocarcinogenesis,and the relationship between c-Myc and telomerase in human hepatocellular carcinoma tissue is unknown.METHODS:We measured hTERTmRNA levels and c-Myc oncoprotein expression in 57 patients with hepatocellular carcinoma using in situhybridization and immunohistochemistry,respectively. The transcription regulation of hTERT was evaluated by transient transfection of pGL3-1375 into the human hepatocellular carcinoma cell line J5. To determine the relationship between c-Myc and the hTERTpromoter, a 1375-bp DNA fragment encompassing the promoter was placed upstream of the luciferase reporter gene and transiently transfected into the cell line. Two additional hTERT promoter constructs (-776 and -100 bp region) and an hTERT promoter-LUC construct containing 2 c-Myc mutations (pGL3-181 MycMT) were also used for luciferase assays.RESULTS:In 30 of 57 cases (52%), hTERTmRNA expression was associated with c-Myc protein expression. However,16 of 57 cases (28%) showed strong hTERTmRNA detection without c-Myc protein expression, and 11 cases (19%) showed weak hTERTmRNA expression and strong c-Myc expression.Although luciferase activity was decreased between upstream 1375 bp and 776 bp, there was no significant difference between upstream 776 bp and 100 bp. Finally, there was no significant decrease in activity after transfection of the hTERT promoter-LUC construct.CONCLUSION:The results indicate that c-Myc does not play a major role in gene regulation of the catalytic subunit of telomerase (hTERT) in human hepatocellular carcinoma.Other regulatory elements or epigenetic phenomena should be further investigated to understand hTERTgene regulation in human hepatocellular carcinoma.
文摘AIM:It is difficult to differentiate gallstone dyspepsia and functional dyspepsia by clinical symptoms and signs. We hypothesized that gallstone dyspepsia was related to abnormal gallbladder motility. We aimed to differentiate gallstone dyspepsia from functional dyspepsia by measuring gallbladder motility.METHODS: We measured gallbladder volume changes in response to gastric distension (saline 500mL) and fatty meal in 10normal volunteers (controls) and 62 patients with gallstones and dyspepsia before cholecystectomy. Forty cholecystectomized patients were symptom free or had improvement (group I), while the remaining 22 patients had persistent dyspepsia (group Ⅱ). Gallbladder volume change and ejection fraction were analyzed and compared among the three groups.RESULTS:In group I, there were significant decreases in gallbladder volumes 5-25 rain after gastric distension,compared to fasting volumes. Compared to normal volunteers and group Ⅱ, group I had significantly decreased gallbladder volumes 10-20min after drinking 500mL of normal saline and 10 to 50min after eating fatty meal.CONCLUSION:Our results support the hypothesis that increased gallbladder contraction after gastric distension or fatty meal may be related to dyspeptic symptoms in uncomplicated gallstone disease. These findings may be useful in differentiating functional dyspepsia from gallstone dyspepsia, patients with the latter disease may benefit from laparoscopic cholecystectomy.
