AIM: To evaluate the effects of sulindac in inducing growth inhibition and apoptosis of human gastric cancer cells in comparison with human hepatocellular carcinoma (HCC) cells. METHODS: The human gastric cancer cell ...AIM: To evaluate the effects of sulindac in inducing growth inhibition and apoptosis of human gastric cancer cells in comparison with human hepatocellular carcinoma (HCC) cells. METHODS: The human gastric cancer cell lines MKN45 and MKN28 and human hepatocellular carcinoma cell lines HepG(2) and SMMC7721 were used for the study. Anti-proliferative effect was measured by MTT assay, and apoptosis was determined by Hoechst-33258 staining, electronography and DNA fragmentation. The protein of cyclooxygenase-2 (COX-2) and Bcl-2 were detected by Western dot blotting. RESULTS: Sulindac could initiate growth inhibition and apoptosis of MKN45, MKN28, HepG(2) and SMMC7721 cells in a dose-and time-dependent manner. Growth inhibitory activity and apoptosis were more sensitive in HepG(2) cells than in SMMC7721 cells, MKN45 and MKN28 cells. After 24 hours incubation with sulindac at 2mmol x L(-1) and 4mmol x L(-1), the level of COX-2 and Bcl-2 protein were lowered in MKN45, SMMC7721 and HepG(2) cells but not in MKN28 cells. CONCLUSION: Sulindac could inhibit the growth of gastric cancer cells and HCC cells effectively in vitro by apoptosis induction, which was associated with regression of COX-2 and Bcl-2 expression. The growth inhibition and apoptosis of HCC cells were greater than that of human gastric cancer cells. The different effects of apoptosis in gastric cancer cells may be related to the differentiation of the cells.展开更多
Peptic ulcer disease is a multifactorial and complex disease involving gastric and duodenal ulcers.Despite medical advances,the management of peptic ulcer and its complications remains a challenge,with high morbidity ...Peptic ulcer disease is a multifactorial and complex disease involving gastric and duodenal ulcers.Despite medical advances,the management of peptic ulcer and its complications remains a challenge,with high morbidity and death rates for the disease.An accumulating body of evidence suggests that,among a broad reach of natural molecules,dietary polyphenols with multiple biological mechanisms of action play a pivotal part in the management of gastric and duodenal ulcers.The current review confirmed that dietary polyphenols possess protective and therapeutic potential in peptic ulcer mediated by:improving cytoprotection,re-epithelialization,neovascularization,and angiogenesis; up-regulating tissue growth factors and prostaglandins; down-regulating anti-angiogenic factors; enhancing endothelial nitric oxide synthasederived NO; suppressing oxidative mucosal damage; amplifying antioxidant performance,antacid,and antisecretory activity; increasing endogenous mucosal defensive agents; and blocking Helicobacter pylori colonization associated gastric morphological changes and gastroduodenal inflammation and ulceration.In addition,anti-inflammatory activity due to downregulation of proinflammatory cytokines and cellular and int e r c e llular adhe s ion age nt s,s uppr e s s ing leukocyte-endothelium interaction,inhibiting nuclear signaling pathways of inflammatory process,and modulating intracellular transduction and transcription pathways have key roles in the anti-ulcer action of dietary polyphenols.In conclusion,administration of a significant amount of dietary polyphenols in the human diet or as part of dietary supplementation along with conventional treatment can result in perfect security and treatment of peptic ulcer.Further welldesigned preclinical and clinical tests are recommended in order to recognize higher levels of evidence for the confirmation of bioefficacy and safety of dietary polyphenols in the management of peptic ulcer.展开更多
Low-dose aspirin(LDA) is clinically used for the prevention of cardiovascular and cerebrovascular events with the advent of an aging society.On the other hand,a very low dose of aspirin(10 mg daily) decreases the gast...Low-dose aspirin(LDA) is clinically used for the prevention of cardiovascular and cerebrovascular events with the advent of an aging society.On the other hand,a very low dose of aspirin(10 mg daily) decreases the gastric mucosal prostaglandin levels and causes significant gastric mucosal damage.The incidence of LDAinduced gastrointestinal mucosal injury and bleeding has increased.It has been noticed that the incidence of LDA-induced gastrointestinal hemorrhage has increased more than that of non-aspirin non-steroidal anti-inflammatory drug(NSAID)-induced lesions.The pathogenesis related to inhibition of cyclooxygenase(COX)-1 includes reduced mucosal flow,reduced mucus and bicarbonate secretion,and impaired platelet aggregation.The pathogenesis related to inhibition of COX-2 involves reduced angiogenesis and increased leukocyte adherence.The pathogenic mechanisms related to direct epithelial damage are acid back diffusion and impaired platelet aggregation.The factors associated with an increased risk of upper gastrointestinal(GI) complications in subjects taking LDA are aspirin dose,history of ulcer or upper GI bleeding,age > 70 years,concomitant use of non-aspirin NSAIDs including COX-2-selective NSAIDs,and Helicobacter pylori(H.pylori) infection.Moreover,no significant differences have been found between ulcer and non-ulcer groups in the frequency and severity of symptoms such as nausea,acid regurgitation,heartburn,and bloating.It has been shown that the ratios of ulcers located in the body,fundus and cardia are significantly higher in bleeding patients than the ratio of gastroduodenal ulcers in patients taking LDA.Proton pump inhibitors reduce the risk of developing gastric and duodenal ulcers.In contrast to NSAIDinduced gastrointestinal ulcers,a well-tolerated histamine H2-receptor antagonist is reportedly effective in prevention of LDA-induced gastrointestinal ulcers.The eradication of H.pylori is equivalent to treatment with omeprazole in preventing recurrent bleeding.Continuous aspirin therapy for patients 展开更多
Many epidemiological studies demonstrate that treatment with non-steroidal anti-inflammatory drugs （NSAIDs） reduce the incidence and mortality of certain malignancies, especially gastrointestinal cancer. The cycloox...Many epidemiological studies demonstrate that treatment with non-steroidal anti-inflammatory drugs （NSAIDs） reduce the incidence and mortality of certain malignancies, especially gastrointestinal cancer. The cyclooxygenase （COX） enzymes are well-known targets of NSAIDs. However, conventional NSAIDs nonselectively inhibit both the constitutive form COX-1, and the inducible form COX-2. Recent evidence indicates that COX-2 is an important molecular target for anticancer therapies. Its expression is undetectable in most normal tissues, and is highly induced by proinflammatory cytokines, mitogens, tumor promoters and growth factors. It is now well-established that COX-2 is chronically overexpressed in many premalignant, malignant, and metastastic cancers, including hepatocellular carcinoma （HCC）. Overexpression of COX-2 in patients with HCC is generally higher in welldifferentiated HCCs compared with less-differentiated HCCs or histologically normal liver, suggesting that COX-2 may be involved in the early stages of hepatocarcinogenesis, and increased expression of COX-2 in noncancerous liver tissue has been significantly associated with shorter disease-free survival in patients with HCC. In tumors, overexpression of COX-2 leads to an increase in prostaglandin （PG） levels, which affect many mechanisms involved in carcinogenesis, such as angiogenesis, inhibition of apoptosis, stimulation of cell growth as well as the invasiveness and metastatic potential of tumor cells. The availability of novel agents that selectively inhibit COX-2 （COXIB）, has contributed to shedding light on the role of this molecule. Experimental studies on animal models of liver cancer have shown that NSAIDs, including both selective and non-selective COX-2 inhibitors, exert chemopreventive as well as therapeutic effects. However, the key mechanism by which COX-2 inhibitors affect HCC cell growth is as yet not fully understood. Increasing evidence suggests the involvement of molecular targets other than COX-2 in the antiprol展开更多
This article reviews the pathogenic mechanism of nonsteroidal anti-inflammatory drug(NSAID)-induced gastric damage,focusing on the relation between cyclooxygenase(COX) inhibition and various functional events.NSAIDs,s...This article reviews the pathogenic mechanism of nonsteroidal anti-inflammatory drug(NSAID)-induced gastric damage,focusing on the relation between cyclooxygenase(COX) inhibition and various functional events.NSAIDs,such as indomethacin,at a dose that inhibits prostaglandin(PG) production,enhance gastric motility,resulting in an increase in mucosal permeability,neutrophil infiltration and oxyradical production,and eventually producing gastric lesions.These lesions are prevented by pretreatment with PGE 2 and antisecretory drugs,and also via an atropine-sensitive mechanism,not related to antisecretory action.Although neither rofecoxib(a selective COX-2 inhibitor) nor SC-560(a selective COX-1 inhibitor) alone damages the stomach,the combined administration of these drugs provokes gastric lesions.SC-560,but not rofecoxib,decreases prostaglandin E 2(PGE 2) production and causes gastric hypermotility and an increase in mucosal permeability.COX-2 mRNA is expressed in the stomach after administration of indomethacin and SC-560 but not rofecoxib.The up-regulation of indomethacin-induced COX-2 expression is prevented by atropine at a dose that inhibits gastric hypermotility.In addition,selective COX-2 inhibitors have deleterious influences on the stomach when COX-2 is overexpressed under various conditions,including adrenalectomy,arthritis,and Helicobacter pylori-infection.In summary,gastric hypermotility plays a primary role in the pathogenesis of NSAID-induced gastric damage,and the response,causally related with PG deficiency due to COX-1 inhibition,occurs prior to other pathogenic events such as increased mucosal permeability;and the ulcerogenic properties of NSAIDs require the inhibition of both COX-1 and COX-2,the inhibition of COX-1 upregulates COX-2 expression in association with gastric hypermotility,and PGs produced by COX-2 counteract the deleterious effect of COX-1 inhibition.展开更多
Endoscopic retrograde cholangiopancreatography(ERCP) has a significant complication rate which can be lowered by adopting technical variations of proven beneficial effect and prophylactic maneuvers such as pancreatic... Endoscopic retrograde cholangiopancreatography(ERCP) has a significant complication rate which can be lowered by adopting technical variations of proven beneficial effect and prophylactic maneuvers such as pancreatic stenting during ERCP or periprocedural non-steroidal anti-inflammatory drug administration.However,adoption of these prophylactic maneuvers by endoscopists is not uniform.In this editorial we discuss the beneficial effects of the aforementioned maneuvers.展开更多
基金Supported by Asahi Medical Foundation,No.00-2000-03
文摘AIM: To evaluate the effects of sulindac in inducing growth inhibition and apoptosis of human gastric cancer cells in comparison with human hepatocellular carcinoma (HCC) cells. METHODS: The human gastric cancer cell lines MKN45 and MKN28 and human hepatocellular carcinoma cell lines HepG(2) and SMMC7721 were used for the study. Anti-proliferative effect was measured by MTT assay, and apoptosis was determined by Hoechst-33258 staining, electronography and DNA fragmentation. The protein of cyclooxygenase-2 (COX-2) and Bcl-2 were detected by Western dot blotting. RESULTS: Sulindac could initiate growth inhibition and apoptosis of MKN45, MKN28, HepG(2) and SMMC7721 cells in a dose-and time-dependent manner. Growth inhibitory activity and apoptosis were more sensitive in HepG(2) cells than in SMMC7721 cells, MKN45 and MKN28 cells. After 24 hours incubation with sulindac at 2mmol x L(-1) and 4mmol x L(-1), the level of COX-2 and Bcl-2 protein were lowered in MKN45, SMMC7721 and HepG(2) cells but not in MKN28 cells. CONCLUSION: Sulindac could inhibit the growth of gastric cancer cells and HCC cells effectively in vitro by apoptosis induction, which was associated with regression of COX-2 and Bcl-2 expression. The growth inhibition and apoptosis of HCC cells were greater than that of human gastric cancer cells. The different effects of apoptosis in gastric cancer cells may be related to the differentiation of the cells.
基金Supported by National Elites Foundation of Iran(partly)
文摘Peptic ulcer disease is a multifactorial and complex disease involving gastric and duodenal ulcers.Despite medical advances,the management of peptic ulcer and its complications remains a challenge,with high morbidity and death rates for the disease.An accumulating body of evidence suggests that,among a broad reach of natural molecules,dietary polyphenols with multiple biological mechanisms of action play a pivotal part in the management of gastric and duodenal ulcers.The current review confirmed that dietary polyphenols possess protective and therapeutic potential in peptic ulcer mediated by:improving cytoprotection,re-epithelialization,neovascularization,and angiogenesis; up-regulating tissue growth factors and prostaglandins; down-regulating anti-angiogenic factors; enhancing endothelial nitric oxide synthasederived NO; suppressing oxidative mucosal damage; amplifying antioxidant performance,antacid,and antisecretory activity; increasing endogenous mucosal defensive agents; and blocking Helicobacter pylori colonization associated gastric morphological changes and gastroduodenal inflammation and ulceration.In addition,anti-inflammatory activity due to downregulation of proinflammatory cytokines and cellular and int e r c e llular adhe s ion age nt s,s uppr e s s ing leukocyte-endothelium interaction,inhibiting nuclear signaling pathways of inflammatory process,and modulating intracellular transduction and transcription pathways have key roles in the anti-ulcer action of dietary polyphenols.In conclusion,administration of a significant amount of dietary polyphenols in the human diet or as part of dietary supplementation along with conventional treatment can result in perfect security and treatment of peptic ulcer.Further welldesigned preclinical and clinical tests are recommended in order to recognize higher levels of evidence for the confirmation of bioefficacy and safety of dietary polyphenols in the management of peptic ulcer.
文摘Low-dose aspirin(LDA) is clinically used for the prevention of cardiovascular and cerebrovascular events with the advent of an aging society.On the other hand,a very low dose of aspirin(10 mg daily) decreases the gastric mucosal prostaglandin levels and causes significant gastric mucosal damage.The incidence of LDAinduced gastrointestinal mucosal injury and bleeding has increased.It has been noticed that the incidence of LDA-induced gastrointestinal hemorrhage has increased more than that of non-aspirin non-steroidal anti-inflammatory drug(NSAID)-induced lesions.The pathogenesis related to inhibition of cyclooxygenase(COX)-1 includes reduced mucosal flow,reduced mucus and bicarbonate secretion,and impaired platelet aggregation.The pathogenesis related to inhibition of COX-2 involves reduced angiogenesis and increased leukocyte adherence.The pathogenic mechanisms related to direct epithelial damage are acid back diffusion and impaired platelet aggregation.The factors associated with an increased risk of upper gastrointestinal(GI) complications in subjects taking LDA are aspirin dose,history of ulcer or upper GI bleeding,age > 70 years,concomitant use of non-aspirin NSAIDs including COX-2-selective NSAIDs,and Helicobacter pylori(H.pylori) infection.Moreover,no significant differences have been found between ulcer and non-ulcer groups in the frequency and severity of symptoms such as nausea,acid regurgitation,heartburn,and bloating.It has been shown that the ratios of ulcers located in the body,fundus and cardia are significantly higher in bleeding patients than the ratio of gastroduodenal ulcers in patients taking LDA.Proton pump inhibitors reduce the risk of developing gastric and duodenal ulcers.In contrast to NSAIDinduced gastrointestinal ulcers,a well-tolerated histamine H2-receptor antagonist is reportedly effective in prevention of LDA-induced gastrointestinal ulcers.The eradication of H.pylori is equivalent to treatment with omeprazole in preventing recurrent bleeding.Continuous aspirin therapy for patients
基金Supported by a grant from the Associazione Italiana per la Ricerca sul Cancro and from the Italian Ministero dell'Universitàedella Ricerca Scientifica (ex 60%, year 2003)
文摘Many epidemiological studies demonstrate that treatment with non-steroidal anti-inflammatory drugs （NSAIDs） reduce the incidence and mortality of certain malignancies, especially gastrointestinal cancer. The cyclooxygenase （COX） enzymes are well-known targets of NSAIDs. However, conventional NSAIDs nonselectively inhibit both the constitutive form COX-1, and the inducible form COX-2. Recent evidence indicates that COX-2 is an important molecular target for anticancer therapies. Its expression is undetectable in most normal tissues, and is highly induced by proinflammatory cytokines, mitogens, tumor promoters and growth factors. It is now well-established that COX-2 is chronically overexpressed in many premalignant, malignant, and metastastic cancers, including hepatocellular carcinoma （HCC）. Overexpression of COX-2 in patients with HCC is generally higher in welldifferentiated HCCs compared with less-differentiated HCCs or histologically normal liver, suggesting that COX-2 may be involved in the early stages of hepatocarcinogenesis, and increased expression of COX-2 in noncancerous liver tissue has been significantly associated with shorter disease-free survival in patients with HCC. In tumors, overexpression of COX-2 leads to an increase in prostaglandin （PG） levels, which affect many mechanisms involved in carcinogenesis, such as angiogenesis, inhibition of apoptosis, stimulation of cell growth as well as the invasiveness and metastatic potential of tumor cells. The availability of novel agents that selectively inhibit COX-2 （COXIB）, has contributed to shedding light on the role of this molecule. Experimental studies on animal models of liver cancer have shown that NSAIDs, including both selective and non-selective COX-2 inhibitors, exert chemopreventive as well as therapeutic effects. However, the key mechanism by which COX-2 inhibitors affect HCC cell growth is as yet not fully understood. Increasing evidence suggests the involvement of molecular targets other than COX-2 in the antiprol
文摘This article reviews the pathogenic mechanism of nonsteroidal anti-inflammatory drug(NSAID)-induced gastric damage,focusing on the relation between cyclooxygenase(COX) inhibition and various functional events.NSAIDs,such as indomethacin,at a dose that inhibits prostaglandin(PG) production,enhance gastric motility,resulting in an increase in mucosal permeability,neutrophil infiltration and oxyradical production,and eventually producing gastric lesions.These lesions are prevented by pretreatment with PGE 2 and antisecretory drugs,and also via an atropine-sensitive mechanism,not related to antisecretory action.Although neither rofecoxib(a selective COX-2 inhibitor) nor SC-560(a selective COX-1 inhibitor) alone damages the stomach,the combined administration of these drugs provokes gastric lesions.SC-560,but not rofecoxib,decreases prostaglandin E 2(PGE 2) production and causes gastric hypermotility and an increase in mucosal permeability.COX-2 mRNA is expressed in the stomach after administration of indomethacin and SC-560 but not rofecoxib.The up-regulation of indomethacin-induced COX-2 expression is prevented by atropine at a dose that inhibits gastric hypermotility.In addition,selective COX-2 inhibitors have deleterious influences on the stomach when COX-2 is overexpressed under various conditions,including adrenalectomy,arthritis,and Helicobacter pylori-infection.In summary,gastric hypermotility plays a primary role in the pathogenesis of NSAID-induced gastric damage,and the response,causally related with PG deficiency due to COX-1 inhibition,occurs prior to other pathogenic events such as increased mucosal permeability;and the ulcerogenic properties of NSAIDs require the inhibition of both COX-1 and COX-2,the inhibition of COX-1 upregulates COX-2 expression in association with gastric hypermotility,and PGs produced by COX-2 counteract the deleterious effect of COX-1 inhibition.
文摘 Endoscopic retrograde cholangiopancreatography(ERCP) has a significant complication rate which can be lowered by adopting technical variations of proven beneficial effect and prophylactic maneuvers such as pancreatic stenting during ERCP or periprocedural non-steroidal anti-inflammatory drug administration.However,adoption of these prophylactic maneuvers by endoscopists is not uniform.In this editorial we discuss the beneficial effects of the aforementioned maneuvers.
