AIM: To review the characteristics of esophageal carcinoma in recent 30 years in the epidemiological investigation. METHODS: A total of 1 520 cases of esophageal carcinoma in the First Affiliated Hospital of Zhejiang ...AIM: To review the characteristics of esophageal carcinoma in recent 30 years in the epidemiological investigation. METHODS: A total of 1 520 cases of esophageal carcinoma in the First Affiliated Hospital of Zhejiang University Medical College admitted from 1970 until now were reviewed. Their age, gender, position of carcinoma and histological type were analyzed. RESULTS: The morbidity of esophageal carcinoma was increasing during the observation period. Compared with the 1970s (9.5%), the ratio of adenocarcinoma significantly increased after the 1980s (19.1%). The difference was significant (P≤0.05). CONCLUSION: The morbidity of esophageal adenocarcinoma was increasing and advanced clinical study should be strengthened.展开更多
AIM: To investigate the inhibitory effect of ubiquitin-proteasome pathway (UPP) on proliferation of esophageal carcinoma cells.METHODS: Esophageal carcinoma cell strain EC9706 was treated with MG-132 to inhibit its UP...AIM: To investigate the inhibitory effect of ubiquitin-proteasome pathway (UPP) on proliferation of esophageal carcinoma cells.METHODS: Esophageal carcinoma cell strain EC9706 was treated with MG-132 to inhibit its UPP specificity. Cell growth suppression was evaluated with 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. DNA synthesis was evaluated by ^3H-thymidine (^3H-TdR) incorporation. Morphologic changes of cells were observed under microscope. Activity of telomerase was examined by telomeric repeat amplification protocol (TRAP) of PCRELISA. Cell cycle and apoptosis were detected by flow cytometry (FCM). DNA fragment analysis was used to confirm the presence of apoptosis. Expression of p27^kip1 was detected by immunocytochemical technique. RESULTS: After exposed to MG-132, the growth and value of ^3H-TdR incorporation of EC9706 cells were obviously inhibited. Cells became round, small and exfoliative under microscope. TRAP PCR-ELISA showed that light absorption of cells gradually decreased after exposed to 5 μmol/L of MG-132 for 24, 48, 72 and 96 h (P<0.01). The percentage of cells at G0/G1 phase was increased and that at S and G2/M was decreased (P<0.01). The rate of apoptotic cells treated with 5 μmol/L of MG-132 for 48 and 96 h was 31.7% and 66.4%, respectively. Agarose electrophoresis showed marked ladders. In addition, the positive signals of p27^kip1 were located in cytoplasm and nuclei in MG-132 group in contrast to cytoplasm staining in control group. CONCLUSION: MG-132 can obviously inhibit proliferation of EC9706 cells and induce apoptosis. The mechanisms include upregulation of p27^kip1 expression, G1 arrest and depression of telomerase activity. The results indicate that inhibiting UPP is a novel strategy for esophageal carcinoma therapy.展开更多
AIM: To determine the correlation between methylation status of 5' CpG island of cyclooxygenase-2 (COX-2) gene and protein expression in gastric cancer tissues for distinguishing the molecular characters of gastri...AIM: To determine the correlation between methylation status of 5' CpG island of cyclooxygenase-2 (COX-2) gene and protein expression in gastric cancer tissues for distinguishing the molecular characters of gastric cancers. METHODS: Methylation status of 5' CpG island of COX-2 gene was studied by PCR amplification after HpaⅡ and Hha I restrictive enzyme digestion;COX-2 expression was evaluated by immunohistochemical method. RESULTS: Hpa Ⅱ and HhaI site were all methylated in 12 normal gastric mucosa tissues, whereas they were demethylated in 77.27% (34/44) and 84.09% (37/44) gastric cancer tissues,respectively.Expression of COX-2 was detected in 68.18% (30/44) gastric cancer tissues, but no expression was found in normal gastric mucosa tissues. In gastric cancer tissues, COX-2 expression was correlated significantly with HpaⅡ site demethylation (29/30 vs 5/14, P<0.001 and HhaI site demethylation (28/30 vs 9/14,P<0.05). CONCLUSION: The demethylation of 5' CpG island of gene is necessary for COX-2 expression in human gastric cancer. The expression status of COX-2 may provide theoretical basis for COX-2 targeting gastric cancer treatments.展开更多
文摘AIM: To review the characteristics of esophageal carcinoma in recent 30 years in the epidemiological investigation. METHODS: A total of 1 520 cases of esophageal carcinoma in the First Affiliated Hospital of Zhejiang University Medical College admitted from 1970 until now were reviewed. Their age, gender, position of carcinoma and histological type were analyzed. RESULTS: The morbidity of esophageal carcinoma was increasing during the observation period. Compared with the 1970s (9.5%), the ratio of adenocarcinoma significantly increased after the 1980s (19.1%). The difference was significant (P≤0.05). CONCLUSION: The morbidity of esophageal adenocarcinoma was increasing and advanced clinical study should be strengthened.
文摘AIM: To investigate the inhibitory effect of ubiquitin-proteasome pathway (UPP) on proliferation of esophageal carcinoma cells.METHODS: Esophageal carcinoma cell strain EC9706 was treated with MG-132 to inhibit its UPP specificity. Cell growth suppression was evaluated with 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. DNA synthesis was evaluated by ^3H-thymidine (^3H-TdR) incorporation. Morphologic changes of cells were observed under microscope. Activity of telomerase was examined by telomeric repeat amplification protocol (TRAP) of PCRELISA. Cell cycle and apoptosis were detected by flow cytometry (FCM). DNA fragment analysis was used to confirm the presence of apoptosis. Expression of p27^kip1 was detected by immunocytochemical technique. RESULTS: After exposed to MG-132, the growth and value of ^3H-TdR incorporation of EC9706 cells were obviously inhibited. Cells became round, small and exfoliative under microscope. TRAP PCR-ELISA showed that light absorption of cells gradually decreased after exposed to 5 μmol/L of MG-132 for 24, 48, 72 and 96 h (P<0.01). The percentage of cells at G0/G1 phase was increased and that at S and G2/M was decreased (P<0.01). The rate of apoptotic cells treated with 5 μmol/L of MG-132 for 48 and 96 h was 31.7% and 66.4%, respectively. Agarose electrophoresis showed marked ladders. In addition, the positive signals of p27^kip1 were located in cytoplasm and nuclei in MG-132 group in contrast to cytoplasm staining in control group. CONCLUSION: MG-132 can obviously inhibit proliferation of EC9706 cells and induce apoptosis. The mechanisms include upregulation of p27^kip1 expression, G1 arrest and depression of telomerase activity. The results indicate that inhibiting UPP is a novel strategy for esophageal carcinoma therapy.
文摘AIM: To determine the correlation between methylation status of 5' CpG island of cyclooxygenase-2 (COX-2) gene and protein expression in gastric cancer tissues for distinguishing the molecular characters of gastric cancers. METHODS: Methylation status of 5' CpG island of COX-2 gene was studied by PCR amplification after HpaⅡ and Hha I restrictive enzyme digestion;COX-2 expression was evaluated by immunohistochemical method. RESULTS: Hpa Ⅱ and HhaI site were all methylated in 12 normal gastric mucosa tissues, whereas they were demethylated in 77.27% (34/44) and 84.09% (37/44) gastric cancer tissues,respectively.Expression of COX-2 was detected in 68.18% (30/44) gastric cancer tissues, but no expression was found in normal gastric mucosa tissues. In gastric cancer tissues, COX-2 expression was correlated significantly with HpaⅡ site demethylation (29/30 vs 5/14, P<0.001 and HhaI site demethylation (28/30 vs 9/14,P<0.05). CONCLUSION: The demethylation of 5' CpG island of gene is necessary for COX-2 expression in human gastric cancer. The expression status of COX-2 may provide theoretical basis for COX-2 targeting gastric cancer treatments.
