Objective To study the relationship between telomerase activity and biological behavior in human gastric cancer cells and appraise the clinical significance of detecting telomerase activity.Methods The telomerase acti...Objective To study the relationship between telomerase activity and biological behavior in human gastric cancer cells and appraise the clinical significance of detecting telomerase activity.Methods The telomerase activity in 47 gastric cancer tissue samples , their matched normal tissues, 7 gastric ulcer and 2 gastric cancer cell lines was detected using a PCR-based non-radioisotopic telomeric repeat amplification protocol (TRAP) assay. Results None of the 47 samples from normal gastric tissues expressed telomerase activity. The 41 of 47 cases of gastric cancer presented telomerase activity with an 87.2 % positive rate (P < 0.001). 2/2 gastric cancer cell lines and 0/7 gastric ulcer line were also positive for telomerase activity. The activity of telomerase was associated with the pathological differentiation of gastric cancer. Conclusion Telomerase activity may be related to the biological behavior of gastric cancer and can help in assessing the malignant potential of gastric cancer. Telomerase activity will be a good diagnostic marker for the detection of gastric cancer.展开更多
AIM: To evaluate the efficacy of telomerase activity assay and peritoneal lavage cytology (PLC) examination in peritoneal lavage fluid for the prediction of peritoneal metastasis in gastric cancer patients, and to ...AIM: To evaluate the efficacy of telomerase activity assay and peritoneal lavage cytology (PLC) examination in peritoneal lavage fluid for the prediction of peritoneal metastasis in gastric cancer patients, and to explore the relationship between telomerase activity and proliferating cell nuclear antigen expression.METHODS: Telomeric repeated amplification protocol (TRAP)-enzyme-linked immunosorbent assay (ELISA) was performed to measure the telomerase activity in 60 patients with gastric cancer and 50 with peptic ulcer. PLC analysis of the 60 patients with gastric cancer was used for comparison. The proliferating cell nuclear antigen (PCNA) in gastric carcinoma was immunohistochemically examined.RESULTS: The telomerase activity and PLC positive rate in peritoneal lavage fluid from patients with gastric cancer was 41.7% (25/60), and 25.0% (15/60), respectively. The positive rate of telomerase activity was significantly higher than that Qf PLC in the group of pT, (15/16 vs 9/16, P 〈 0.05), P1-3 (13/13 vs 9/13, P 〈 0.05) and diffuse type (22/42 vs 13/42, P 〈 0.05). The patients with positive telomerase activity, peritoneal metastasis, and serosal invasion had significantly higher levels of average PCNA proliferation index (PI), (55.00 ± 6.59 vs 27.43 ± 7.72, 57.26 ±10.18 vs 29.15 ±8.31, and 49.82 ± 6.74 vs 24.65 ±7.33, respectively, P 〈 0.05).CONCLUSION: The TRAP assay for telomerase activity is a useful adjunct for cytologic method in the diagnosis of peritoneal micrometastasis and well related to higher proliferating activity of gastric cancer. The results of this study also suggest a promising future therapeutic strategy for treating peritoneal dissemination based on telomerase inhibition.展开更多
AIM: To determine the proteolytic activity and expression of gelatinase B in serum of gastric cancer patients and their correlation with the stage of the tumor. METHODS: Sera from 23 patients who underwent surgery f...AIM: To determine the proteolytic activity and expression of gelatinase B in serum of gastric cancer patients and their correlation with the stage of the tumor. METHODS: Sera from 23 patients who underwent surgery for primary gastric cancer as the experimental group and from 11 as the control group were used to determine the proteolytic activity and its inhibition by EDTA and 1,10-phenanthroline. Gelatinase B activity was detected by SDS polyacrylamide gel electrophoresis (SDS-PAGE) and SDS-PAGE zymography. RESULTS: Proteolytic enzyme activity was increased in gastric cancer patients when compared to the control group (,0〈0.05). The proteinases were determined to be metalloproteinases upon inhibition test with specific metalloproteinase inhibitors 1,10-phenanthroline (P〈0.05) and EDTA (P〈0.01). SDS-PAGE and SDS-PAGE zymography revealed gelatinase B (proMMP-9) activity and its molecular mass of 92 ku. CONCLUSION: Proteinase activity is overexpressed in serum of gastric cancer patients. Gelatinase B in serum plays an important role in the progression of gastric cancer. ProMMP-9 can be used as a marker for invasiveness of gastric cancer.Proteolytic activity; Inhibition展开更多
AIM:To test whether the expression and activity of H,K-ATPase in parietal cells would be affected by cigarette smoke extract.METHODS: Extracts of cigarette smoke were administered into mice by gastric gavage (5 mg/kg ...AIM:To test whether the expression and activity of H,K-ATPase in parietal cells would be affected by cigarette smoke extract.METHODS: Extracts of cigarette smoke were administered into mice by gastric gavage (5 mg/kg body weight/day) for 3 d or in drinking water for 7 or 14 d. For the latter, each day a mouse consumed 5 mL water containing extracts of two cigarettes, on average. Control littermate mice received only vehicle. To compare the amount of H,K-ATPase in control and smoke-treated mice, the stomach was processed for Western blotting and immunohistochemical analysis using monoclonal antibodies specific for α- or β-subunits of H,K-ATPase. The p-nitrophenylphospatase activity assay was used as a measurement for K-dependent H,K-ATPase activity.RESULTS: Probed transblots showed an increase in the amount of H,K-ATPase in smoke-treated mice which was confirmed by immunohistochemistry and was found to be due to increased amounts of protein per parietal cell rather than an increased parietal cell number. The increase in the amount of H,K-ATPase was associated with an enhancement of its enzymatic activity. K-dependent activity in control and smoke-treated mice was significantly different (respectively, 0.12 μmol/mg vs 0.27 μmol/mg per minute, P<0.05).CONCLUSION: Administration of cigarette smoke extract is associated with an increase in the amount and activity of H,K-ATPase and hence, smokers are susceptible to development of peptic ulcer.展开更多
AIM: To investigate whether alphastatin could inhibit human gastric cancer growth and furthermore whether sphingosine kinase (SPK) activity is involved in this process. METHODS: Using migration assay, MTT assay an...AIM: To investigate whether alphastatin could inhibit human gastric cancer growth and furthermore whether sphingosine kinase (SPK) activity is involved in this process. METHODS: Using migration assay, MTT assay and Matrigel assay, the effect of alphastatin on vascular endothelial cells (ECs) was evaluated in vitro. SPK and endothelial differentiation gene (EDG)-1, -3, -5 mRNAs were detected by reverse transcription-polymerase chain reaction (RT-PCR). SPK activity assay was used to evaluate the effect of alphastatin on ECs. Matrigel plug assay in nude mice was used to investigate the effect of alphastatin on angiogenesis in vivo. Female nude mice were subcutaneously implanted with human gastric cancer cells (BGC823) for the tumor xenografts studies. Micro vessel density was analyzed in Factor Ⅷ-stained tumor sections by the immunohistochemical SP method. RESULTS: In vitro, alphastatin inhibited the migration and tube formation of ECs, but had no effect on proliferation of ECs. RT-PCR analysis demonstrated that ECs expressed SPK and EDG-1, -3, -5 mRNAs. In vivo, alphastatin sufficiently suppressed neovascularization of the tumor in the nude mice. Daily administration of alphastatin produced significant tumor growth suppression. Immunohistochemical studies of tumor tissues revealed decreased micro vessel density in alphastatin-treated animals as compared with controls. CONCLUSION: Downregulating ECs SPK activity may be one of the mechanisms that alphastatin inhibits gastric cancer angiogenesis. Alphastatin might be a useful and relatively nontoxic adjuvant therapy in the treatment of gastric cancer.展开更多
AIM: To explore the relationship between clinicobiological behavior and the expression levels of telomerase activity, apoptosis, p53 gene and bcl-2 gene in gastrointestinal stromal tumors (GISTs). METHODS: The int...AIM: To explore the relationship between clinicobiological behavior and the expression levels of telomerase activity, apoptosis, p53 gene and bcl-2 gene in gastrointestinal stromal tumors (GISTs). METHODS: The intensity of telomerase activity, apoptosis, p53 and bcl-2 expression in GISTs were detected by telomeric repeat amplification protocol, in situ end-labeling technique, and immunohistochemistry, respectively. RESULTS: The positive rates of telomerase activity of malignant GIST, potential malignant GIST and benign GIST were 85% (17/20), 22.8% (2/9) and 0 (0/9), respectively. The apoptosis indices of malignant GIST, potential malignant GIST, and benign GIST were 11.7±5.4, 30.2±5.6 and 45.2 ±7.2, respectively. The intensity of telomerase activity and apoptosis were related to the biological characteristics of GISTs (85% vs 22.8%, 0, 0; P 〈 0.01 or 11.7±5.4 vs 30.2±5.6, 45.2±7.2, 72.1±9.3; P 〈 0.05). The intensity of telomerase activity was negatively correlated with cellular apoptosis (22.9±8.4 vs 9.5±5.7, P 〈 0.01). The intensity of telomerase activity was positively correlated with/753, bcl-2 expression (40.0% vs 78.9%, 40.0% vs 84.2%; P 〈 0.05). CONCLUSION: The detection of telomerase activity, apoptosis and its control genes in GIST will be helpful for the discrimination of the malignant and benign GIST and evaluation of the prognosis.展开更多
AIM:To investigate the effect and mechanism of oridonin on the gastric cancer cell line HGC-27 in vitro.METHODS:The inhibitory effect of oridonin on HGC-27 cells was detected using the 3-(4,5-dimethylthiazol2-yl)-2,5-...AIM:To investigate the effect and mechanism of oridonin on the gastric cancer cell line HGC-27 in vitro.METHODS:The inhibitory effect of oridonin on HGC-27 cells was detected using the 3-(4,5-dimethylthiazol2-yl)-2,5-diphenyl tetrazolium bromide assay.After treatment with 10 μg/mL oridonin for 24 h and 48 h,the cells were stained with acridine orange/ethidium bromide.The morphologic changes were observed under an inverted fluorescence microscope.DNA fragmen-tation(a hallmark of apoptosis) and lactate dehydrogenase activity were examined using DNA ladder assay and lactate dehydrogenase-release assay.After treated with oridonin(0,1.25,2.5,5 and 10 μg/mL),HGC-27 cells were collected for anexin V-phycoerythrin and 7-amino-actinomycin D double staining and tested by flow cytometric analysis,and oridonin-induced apoptosis in HGC-27 cells was detected.After treatment with oridonin for 24 h,the effects of oridonin on expression of Apaf-1,Bcl-2,Bax,caspase-3 and cytochrome c were also analyzed using reverse-transcript polymerase chain reaction(RT-PCR) and Western blotting.RESULTS:Oridonin significantly inhibited the proliferation of HGC-27 cells in a dose-and time-dependent manner.The inhibition rates of HGC-27 treated with four different concentrations of oridonin for 24 h(1.25,2.5,5 and 10 μg/mL) were 1.78% ± 0.36%,4.96% ± 1.59%,10.35% ± 2.76% and 41.6% ± 4.29%,respectively,which showed a significant difference(P < 0.05).The inhibition rates of HGC-27 treated with oridonin at the four concentrations for 48 h were 14.77% ± 4.21%,21.57% ± 3.75%,30.31% ± 4.91% and 61.19% ± 5.81%,with a significant difference(P < 0.05).The inhibition rates of HGC-27 treated with oridonin for 72 h at the four concentrations were 25.77% ± 4.85%,31.86% ± 3.86%,48.30% ± 4.16% and 81.80% ± 6.72%,with a significant difference(P < 0.05).Cells treated with oridonin showed typical apoptotic features with acridine orange/ethidium bromide staining.After treatment with oridonin,the cells became round,shrank,and developed small buds around the nuclear membrane while forming apoptotic bodies.Lactate dehydrogenase(LDH) release assay showed that after treated with 1.25 μg/mL and 20 μg/mL oridonin for 24 h,LDH release of HGC-27 caused by apoptosis increased from 22.94% ± 3.8% to 52.68% ± 2.4%(P < 0.001).However,the change in the release of LDH caused by necrosis was insignificant,suggesting thatthe major cause of oridonin-induced HGC-27 cell death was apoptosis.Flow cytometric analysis also revealed that oridonin induced significant apoptosis compared with the controls(P < 0.05).And the apoptosis rates of HGC-27 induced by the four different concentrations of oridonin were 5.3% ± 1.02%,12.8% ± 2.53%,28.5% ± 4.23% and 49.6% ± 3.76%,which were in a dose-dependent manner(P < 0.05).After treatment for 24 h,DNA ladder showed that oridonin induced a significant increase in DNA fragmentation in a dosedependent manner.RT-PCR revealed that mRNA expression levels were up-regulated compared with the controls in caspase-3(0.917 ± 0.103 vs 0.357 ± 0.019,P < 0.05),cytochrome c(1.429 ± 0.111 vs 1.002 ± 0.014,P < 0.05),Apaf-1(0.688 ± 0.101 vs 0.242 ± 0.037,P < 0.05) and Bax(0.856 ± 0.101 vs 0.278 ± 0.027,P < 0.05)(P < 0.05),whereas down-regulated in Bcl-2(0.085 ± 0.012 vs 0.175 ± 0.030,P < 0.05).Western blotting analysis also confirmed this result.CONCLUSION:Apoptosis of HGC-27 induced by oridonin may be associated with differential expression of Apaf-1,caspase-3 and cytochrome c,which are highly dependent upon the mitochondrial pathway.展开更多
AIM: To establish whether there are fundamental differences in the biochemistries of adenocarcinomas of the gastroesophageal junction (GEJ) and the squamous cell carcinomas of the lower third of the esophagus (LTE...AIM: To establish whether there are fundamental differences in the biochemistries of adenocarcinomas of the gastroesophageal junction (GEJ) and the squamous cell carcinomas of the lower third of the esophagus (LTE). METHODS: Between February 1, 1997 and February 1, 2000, we obtained tissue samples at the moment of resection from 54 patients for biochemical analysis. The full set of data could be comprehensively analyzed in 47 of 54 patients' samples (81%). Of these, 29 were adenocarcinomas of the GEJ Siewert type Ⅰ (n = 8), type Ⅱ (n = 12), type Ⅲ (n = 9), and 18 presented as squamous cell carcinomas of the LTE. We evaluated the mean values of 11-lysosomal enzyme and 1-cytosol protease activities of the tumorous and surrounding mucosae as well as their relative activities, measured as the ratio of activity in tumor and normal tissues from the same patient. These data were further analyzed to establish the correlation with tumor localization, TNM stage (lymph-node involvement), histological type (papillary, signet-ring cell, tubular), state of differentiation (good, moderate, poor), and survival (≤24 or ≥24 mo). RESULTS: In adenocarcinomas, the activity of α-mannosidase (AMAN), cathepsin B (CB) and dipeptidyl-peptidase Ⅰ (DPP Ⅰ) increased significantly as compared to the normal gastric mucosa. In squamous cell carcinomas of the esophagus, we also found a significant difference in the activity of cathepsin L and tripeptidyl-peptidase Ⅰ in addition to these three. There was a statistical correlation of AMAN, CB, and DPP Ⅰ activity between the level of differentiation of adenocarcinomas of the GEJ and lymph node involvement,because tumors with no lymph node metastases histologically confirmed as well-differentiated, showed a significantly lower activity. The differences in CB and DPP Ⅰ activity correlated well with the differences in survival rates, since the CB and DPP Ⅰ values of those who died within 24 mo following surgical intervention were significantly higher than of those who survived for 2 years or more. CONCLUSION: Adenocarcinomas of the GEJ form a homogenous group from a tumor-biochemical aspect, and differ from the biochemical characteristics of squamous cell carcinomas of the LTE on many points. When adenocarcinomas of the GEJs are examined at the preoperative phase, the ratio of the performed AMAN, CB, and DPP Ⅰ enzymatic activity of the tissue sample from the tumor and adjacent intact mucosa within 2 cm of the tumor may have a prognostic value even in the preoperative examination period, and may indicate that ranking of these patients into the neo-adjuvant treatment group should be considered.展开更多
The mudskipper Boleophthalmus pectinirostris and Chinese black sleeper Bostrichthys sinensis occupy the intertidal zone.However,both species have their own unique diet.The former is an herbivore and the latter is a ca...The mudskipper Boleophthalmus pectinirostris and Chinese black sleeper Bostrichthys sinensis occupy the intertidal zone.However,both species have their own unique diet.The former is an herbivore and the latter is a carnivore.In order to reveal the relationship between digestive enzyme activities and diets in the two species,the activities of protease(P),non-specific bile salt-activated lipase(BAL) and α-amylase(A) were determined in the stomach and intestine of adult mudskipper B.pectinirostris and Chinese black sleeper B.sinensis.The results showed that the activities of protease,BAL and α-amylase in the intestine of B.pectinirostris were significantly(P<0.05) higher than those in the stomach.In B.sinensis,gastric protease activity was not different from the intestinal protease(P>0.05),while BAL and α-amylase activities of the intestine were significantly(P<0.05) higher than those of the stomach.The activity of gastric protease in B.sinensis was significantly(P<0.05) higher than that in B.pectinirostris,while the activities of intestinal protease were not different between the two fish species(P>0.05).BAL activities of the stomach and intestine in B.sinensis were significantly(P<0.05) higher than those in B.pectinirostris,while α-amylase activities of the stomach and intestine in B.pectinirostris were significantly(P<0.05) higher than those in B.sinensis.The ratios of P/BAL,A/P and A/BAL of the digestive tract in B.pectinirostris were 1.5,107.3 and 158.6,respectively;and those in B.sinensis were 0.2,1.6 and 0.2,respectively.It can be concluded that food digestion in the adult B.pectinirostris is mainly carried out in the intestine,whereas in the adult B.sinensis it is initiated in the stomach and finishes in the intestine.The activities of BAL and α-amylase in B.pectinirostris and B.sinensis are well correlated with their diets.However,a clear-cut correlation between protease activity and diets is not found in these two species.展开更多
文摘Objective To study the relationship between telomerase activity and biological behavior in human gastric cancer cells and appraise the clinical significance of detecting telomerase activity.Methods The telomerase activity in 47 gastric cancer tissue samples , their matched normal tissues, 7 gastric ulcer and 2 gastric cancer cell lines was detected using a PCR-based non-radioisotopic telomeric repeat amplification protocol (TRAP) assay. Results None of the 47 samples from normal gastric tissues expressed telomerase activity. The 41 of 47 cases of gastric cancer presented telomerase activity with an 87.2 % positive rate (P < 0.001). 2/2 gastric cancer cell lines and 0/7 gastric ulcer line were also positive for telomerase activity. The activity of telomerase was associated with the pathological differentiation of gastric cancer. Conclusion Telomerase activity may be related to the biological behavior of gastric cancer and can help in assessing the malignant potential of gastric cancer. Telomerase activity will be a good diagnostic marker for the detection of gastric cancer.
基金the National Natural Science Foundation of China, No. 30370639
文摘AIM: To evaluate the efficacy of telomerase activity assay and peritoneal lavage cytology (PLC) examination in peritoneal lavage fluid for the prediction of peritoneal metastasis in gastric cancer patients, and to explore the relationship between telomerase activity and proliferating cell nuclear antigen expression.METHODS: Telomeric repeated amplification protocol (TRAP)-enzyme-linked immunosorbent assay (ELISA) was performed to measure the telomerase activity in 60 patients with gastric cancer and 50 with peptic ulcer. PLC analysis of the 60 patients with gastric cancer was used for comparison. The proliferating cell nuclear antigen (PCNA) in gastric carcinoma was immunohistochemically examined.RESULTS: The telomerase activity and PLC positive rate in peritoneal lavage fluid from patients with gastric cancer was 41.7% (25/60), and 25.0% (15/60), respectively. The positive rate of telomerase activity was significantly higher than that Qf PLC in the group of pT, (15/16 vs 9/16, P 〈 0.05), P1-3 (13/13 vs 9/13, P 〈 0.05) and diffuse type (22/42 vs 13/42, P 〈 0.05). The patients with positive telomerase activity, peritoneal metastasis, and serosal invasion had significantly higher levels of average PCNA proliferation index (PI), (55.00 ± 6.59 vs 27.43 ± 7.72, 57.26 ±10.18 vs 29.15 ±8.31, and 49.82 ± 6.74 vs 24.65 ±7.33, respectively, P 〈 0.05).CONCLUSION: The TRAP assay for telomerase activity is a useful adjunct for cytologic method in the diagnosis of peritoneal micrometastasis and well related to higher proliferating activity of gastric cancer. The results of this study also suggest a promising future therapeutic strategy for treating peritoneal dissemination based on telomerase inhibition.
基金Supported by the Ministry ot Science and Environment Protection of the Republic of Serbia,No.1740,TR-6845B and TD-7032B
文摘AIM: To determine the proteolytic activity and expression of gelatinase B in serum of gastric cancer patients and their correlation with the stage of the tumor. METHODS: Sera from 23 patients who underwent surgery for primary gastric cancer as the experimental group and from 11 as the control group were used to determine the proteolytic activity and its inhibition by EDTA and 1,10-phenanthroline. Gelatinase B activity was detected by SDS polyacrylamide gel electrophoresis (SDS-PAGE) and SDS-PAGE zymography. RESULTS: Proteolytic enzyme activity was increased in gastric cancer patients when compared to the control group (,0〈0.05). The proteinases were determined to be metalloproteinases upon inhibition test with specific metalloproteinase inhibitors 1,10-phenanthroline (P〈0.05) and EDTA (P〈0.01). SDS-PAGE and SDS-PAGE zymography revealed gelatinase B (proMMP-9) activity and its molecular mass of 92 ku. CONCLUSION: Proteinase activity is overexpressed in serum of gastric cancer patients. Gelatinase B in serum plays an important role in the progression of gastric cancer. ProMMP-9 can be used as a marker for invasiveness of gastric cancer.Proteolytic activity; Inhibition
基金Supported by Research Grants from UAE University and Terry Fox Foundation (to Karam SM)
文摘AIM:To test whether the expression and activity of H,K-ATPase in parietal cells would be affected by cigarette smoke extract.METHODS: Extracts of cigarette smoke were administered into mice by gastric gavage (5 mg/kg body weight/day) for 3 d or in drinking water for 7 or 14 d. For the latter, each day a mouse consumed 5 mL water containing extracts of two cigarettes, on average. Control littermate mice received only vehicle. To compare the amount of H,K-ATPase in control and smoke-treated mice, the stomach was processed for Western blotting and immunohistochemical analysis using monoclonal antibodies specific for α- or β-subunits of H,K-ATPase. The p-nitrophenylphospatase activity assay was used as a measurement for K-dependent H,K-ATPase activity.RESULTS: Probed transblots showed an increase in the amount of H,K-ATPase in smoke-treated mice which was confirmed by immunohistochemistry and was found to be due to increased amounts of protein per parietal cell rather than an increased parietal cell number. The increase in the amount of H,K-ATPase was associated with an enhancement of its enzymatic activity. K-dependent activity in control and smoke-treated mice was significantly different (respectively, 0.12 μmol/mg vs 0.27 μmol/mg per minute, P<0.05).CONCLUSION: Administration of cigarette smoke extract is associated with an increase in the amount and activity of H,K-ATPase and hence, smokers are susceptible to development of peptic ulcer.
文摘AIM: To investigate whether alphastatin could inhibit human gastric cancer growth and furthermore whether sphingosine kinase (SPK) activity is involved in this process. METHODS: Using migration assay, MTT assay and Matrigel assay, the effect of alphastatin on vascular endothelial cells (ECs) was evaluated in vitro. SPK and endothelial differentiation gene (EDG)-1, -3, -5 mRNAs were detected by reverse transcription-polymerase chain reaction (RT-PCR). SPK activity assay was used to evaluate the effect of alphastatin on ECs. Matrigel plug assay in nude mice was used to investigate the effect of alphastatin on angiogenesis in vivo. Female nude mice were subcutaneously implanted with human gastric cancer cells (BGC823) for the tumor xenografts studies. Micro vessel density was analyzed in Factor Ⅷ-stained tumor sections by the immunohistochemical SP method. RESULTS: In vitro, alphastatin inhibited the migration and tube formation of ECs, but had no effect on proliferation of ECs. RT-PCR analysis demonstrated that ECs expressed SPK and EDG-1, -3, -5 mRNAs. In vivo, alphastatin sufficiently suppressed neovascularization of the tumor in the nude mice. Daily administration of alphastatin produced significant tumor growth suppression. Immunohistochemical studies of tumor tissues revealed decreased micro vessel density in alphastatin-treated animals as compared with controls. CONCLUSION: Downregulating ECs SPK activity may be one of the mechanisms that alphastatin inhibits gastric cancer angiogenesis. Alphastatin might be a useful and relatively nontoxic adjuvant therapy in the treatment of gastric cancer.
文摘AIM: To explore the relationship between clinicobiological behavior and the expression levels of telomerase activity, apoptosis, p53 gene and bcl-2 gene in gastrointestinal stromal tumors (GISTs). METHODS: The intensity of telomerase activity, apoptosis, p53 and bcl-2 expression in GISTs were detected by telomeric repeat amplification protocol, in situ end-labeling technique, and immunohistochemistry, respectively. RESULTS: The positive rates of telomerase activity of malignant GIST, potential malignant GIST and benign GIST were 85% (17/20), 22.8% (2/9) and 0 (0/9), respectively. The apoptosis indices of malignant GIST, potential malignant GIST, and benign GIST were 11.7±5.4, 30.2±5.6 and 45.2 ±7.2, respectively. The intensity of telomerase activity and apoptosis were related to the biological characteristics of GISTs (85% vs 22.8%, 0, 0; P 〈 0.01 or 11.7±5.4 vs 30.2±5.6, 45.2±7.2, 72.1±9.3; P 〈 0.05). The intensity of telomerase activity was negatively correlated with cellular apoptosis (22.9±8.4 vs 9.5±5.7, P 〈 0.01). The intensity of telomerase activity was positively correlated with/753, bcl-2 expression (40.0% vs 78.9%, 40.0% vs 84.2%; P 〈 0.05). CONCLUSION: The detection of telomerase activity, apoptosis and its control genes in GIST will be helpful for the discrimination of the malignant and benign GIST and evaluation of the prognosis.
基金Supported by Medical and Health Research Foundation of Zhejiang Province,No. 2009B019
文摘AIM:To investigate the effect and mechanism of oridonin on the gastric cancer cell line HGC-27 in vitro.METHODS:The inhibitory effect of oridonin on HGC-27 cells was detected using the 3-(4,5-dimethylthiazol2-yl)-2,5-diphenyl tetrazolium bromide assay.After treatment with 10 μg/mL oridonin for 24 h and 48 h,the cells were stained with acridine orange/ethidium bromide.The morphologic changes were observed under an inverted fluorescence microscope.DNA fragmen-tation(a hallmark of apoptosis) and lactate dehydrogenase activity were examined using DNA ladder assay and lactate dehydrogenase-release assay.After treated with oridonin(0,1.25,2.5,5 and 10 μg/mL),HGC-27 cells were collected for anexin V-phycoerythrin and 7-amino-actinomycin D double staining and tested by flow cytometric analysis,and oridonin-induced apoptosis in HGC-27 cells was detected.After treatment with oridonin for 24 h,the effects of oridonin on expression of Apaf-1,Bcl-2,Bax,caspase-3 and cytochrome c were also analyzed using reverse-transcript polymerase chain reaction(RT-PCR) and Western blotting.RESULTS:Oridonin significantly inhibited the proliferation of HGC-27 cells in a dose-and time-dependent manner.The inhibition rates of HGC-27 treated with four different concentrations of oridonin for 24 h(1.25,2.5,5 and 10 μg/mL) were 1.78% ± 0.36%,4.96% ± 1.59%,10.35% ± 2.76% and 41.6% ± 4.29%,respectively,which showed a significant difference(P < 0.05).The inhibition rates of HGC-27 treated with oridonin at the four concentrations for 48 h were 14.77% ± 4.21%,21.57% ± 3.75%,30.31% ± 4.91% and 61.19% ± 5.81%,with a significant difference(P < 0.05).The inhibition rates of HGC-27 treated with oridonin for 72 h at the four concentrations were 25.77% ± 4.85%,31.86% ± 3.86%,48.30% ± 4.16% and 81.80% ± 6.72%,with a significant difference(P < 0.05).Cells treated with oridonin showed typical apoptotic features with acridine orange/ethidium bromide staining.After treatment with oridonin,the cells became round,shrank,and developed small buds around the nuclear membrane while forming apoptotic bodies.Lactate dehydrogenase(LDH) release assay showed that after treated with 1.25 μg/mL and 20 μg/mL oridonin for 24 h,LDH release of HGC-27 caused by apoptosis increased from 22.94% ± 3.8% to 52.68% ± 2.4%(P < 0.001).However,the change in the release of LDH caused by necrosis was insignificant,suggesting thatthe major cause of oridonin-induced HGC-27 cell death was apoptosis.Flow cytometric analysis also revealed that oridonin induced significant apoptosis compared with the controls(P < 0.05).And the apoptosis rates of HGC-27 induced by the four different concentrations of oridonin were 5.3% ± 1.02%,12.8% ± 2.53%,28.5% ± 4.23% and 49.6% ± 3.76%,which were in a dose-dependent manner(P < 0.05).After treatment for 24 h,DNA ladder showed that oridonin induced a significant increase in DNA fragmentation in a dosedependent manner.RT-PCR revealed that mRNA expression levels were up-regulated compared with the controls in caspase-3(0.917 ± 0.103 vs 0.357 ± 0.019,P < 0.05),cytochrome c(1.429 ± 0.111 vs 1.002 ± 0.014,P < 0.05),Apaf-1(0.688 ± 0.101 vs 0.242 ± 0.037,P < 0.05) and Bax(0.856 ± 0.101 vs 0.278 ± 0.027,P < 0.05)(P < 0.05),whereas down-regulated in Bcl-2(0.085 ± 0.012 vs 0.175 ± 0.030,P < 0.05).Western blotting analysis also confirmed this result.CONCLUSION:Apoptosis of HGC-27 induced by oridonin may be associated with differential expression of Apaf-1,caspase-3 and cytochrome c,which are highly dependent upon the mitochondrial pathway.
文摘AIM: To establish whether there are fundamental differences in the biochemistries of adenocarcinomas of the gastroesophageal junction (GEJ) and the squamous cell carcinomas of the lower third of the esophagus (LTE). METHODS: Between February 1, 1997 and February 1, 2000, we obtained tissue samples at the moment of resection from 54 patients for biochemical analysis. The full set of data could be comprehensively analyzed in 47 of 54 patients' samples (81%). Of these, 29 were adenocarcinomas of the GEJ Siewert type Ⅰ (n = 8), type Ⅱ (n = 12), type Ⅲ (n = 9), and 18 presented as squamous cell carcinomas of the LTE. We evaluated the mean values of 11-lysosomal enzyme and 1-cytosol protease activities of the tumorous and surrounding mucosae as well as their relative activities, measured as the ratio of activity in tumor and normal tissues from the same patient. These data were further analyzed to establish the correlation with tumor localization, TNM stage (lymph-node involvement), histological type (papillary, signet-ring cell, tubular), state of differentiation (good, moderate, poor), and survival (≤24 or ≥24 mo). RESULTS: In adenocarcinomas, the activity of α-mannosidase (AMAN), cathepsin B (CB) and dipeptidyl-peptidase Ⅰ (DPP Ⅰ) increased significantly as compared to the normal gastric mucosa. In squamous cell carcinomas of the esophagus, we also found a significant difference in the activity of cathepsin L and tripeptidyl-peptidase Ⅰ in addition to these three. There was a statistical correlation of AMAN, CB, and DPP Ⅰ activity between the level of differentiation of adenocarcinomas of the GEJ and lymph node involvement,because tumors with no lymph node metastases histologically confirmed as well-differentiated, showed a significantly lower activity. The differences in CB and DPP Ⅰ activity correlated well with the differences in survival rates, since the CB and DPP Ⅰ values of those who died within 24 mo following surgical intervention were significantly higher than of those who survived for 2 years or more. CONCLUSION: Adenocarcinomas of the GEJ form a homogenous group from a tumor-biochemical aspect, and differ from the biochemical characteristics of squamous cell carcinomas of the LTE on many points. When adenocarcinomas of the GEJs are examined at the preoperative phase, the ratio of the performed AMAN, CB, and DPP Ⅰ enzymatic activity of the tissue sample from the tumor and adjacent intact mucosa within 2 cm of the tumor may have a prognostic value even in the preoperative examination period, and may indicate that ranking of these patients into the neo-adjuvant treatment group should be considered.
基金Supported by Natural Science Foundation of China(No.40476056)the Key Projects of Science and Technology of Fujian Province(2003,No.262004SZ01-02)
文摘The mudskipper Boleophthalmus pectinirostris and Chinese black sleeper Bostrichthys sinensis occupy the intertidal zone.However,both species have their own unique diet.The former is an herbivore and the latter is a carnivore.In order to reveal the relationship between digestive enzyme activities and diets in the two species,the activities of protease(P),non-specific bile salt-activated lipase(BAL) and α-amylase(A) were determined in the stomach and intestine of adult mudskipper B.pectinirostris and Chinese black sleeper B.sinensis.The results showed that the activities of protease,BAL and α-amylase in the intestine of B.pectinirostris were significantly(P<0.05) higher than those in the stomach.In B.sinensis,gastric protease activity was not different from the intestinal protease(P>0.05),while BAL and α-amylase activities of the intestine were significantly(P<0.05) higher than those of the stomach.The activity of gastric protease in B.sinensis was significantly(P<0.05) higher than that in B.pectinirostris,while the activities of intestinal protease were not different between the two fish species(P>0.05).BAL activities of the stomach and intestine in B.sinensis were significantly(P<0.05) higher than those in B.pectinirostris,while α-amylase activities of the stomach and intestine in B.pectinirostris were significantly(P<0.05) higher than those in B.sinensis.The ratios of P/BAL,A/P and A/BAL of the digestive tract in B.pectinirostris were 1.5,107.3 and 158.6,respectively;and those in B.sinensis were 0.2,1.6 and 0.2,respectively.It can be concluded that food digestion in the adult B.pectinirostris is mainly carried out in the intestine,whereas in the adult B.sinensis it is initiated in the stomach and finishes in the intestine.The activities of BAL and α-amylase in B.pectinirostris and B.sinensis are well correlated with their diets.However,a clear-cut correlation between protease activity and diets is not found in these two species.