Objective To study the effects of glutaminase (GA) gene blocked by antisense nucleotide on apoptosis of transplanted gastric carcinoma cells in nude mice. Methods The plasmid containing antisense sequence of GA gene was trans-fected into gastric carcinoma cells , then the cells were injected to endermic tissue of nude mice to create animal models of gastric carcinoma. Apoptosis of tumor cells was detected by terminal deoxynucleotidyl transferase2mediated nick end labeling (TUNEL) method. The expression of GA mRNA in tumor tissue was measured by reverse transcription polymerase chain reaction (RT2PCR) technique. Results After the successful transfection of plasmid containing antisense sequence of GA gene into gastric carcinoma cells , the tumor’s growth speed decreased , apoptosis of tumor cells increased , and the expression of GA mRNA also decreased. Conclusion The antisense gene of GA could inhibit the expression of GA gene and significantly increase the apoptosis of gastric carcinoma cells.
Objective To explore the effects of ulinastatin (UTI) on renal apoptosis and expression of bcl-2 in rats with severe acute pancreatitis (SAP). Methods Sixty rats weighing 250-300 g were randomized divided into 3 groups: pseudo-operation group (SO group, n=20), SAP group (n=20) and UTI treated group (UTI group, n=20). The model of SAP was established by retrograde injection of 5% sodium taurocholate solution into the biliopancreatic duct in the rats. Serum Cr and BUN were determined. The left kidneys were resected for light and electronic microscopic study. Renal cell apoptosis was determined by TUNEL. Expression of bcl-2 was detected by immunohistochemical staining of SABC. Results Serum Cr, BUN, renal cell apoptotic index and bcl-2 expression were markedly increased in SAP group compared with SO group （P＜0.05， P＜0.01）, Renal tissue injuries were aggravated in SAP group under light and electronic microscopic study as well. In UTI group, serum Cr, BUN and renal cell apoptotic index were decreased significantly while the expression of bcl-2 increased remarkably and renal tissue injuries relieved compared with SAP group （P＜0.05）. Positive correlations were found between the renal cell apoptotic index and BUN as well as Cr (r=0.807, P＜0.05; r=0.812, P＜0.05). Conclusion The protective effect of UTI on SAP renal injury is probably through increasing bcl-2 expression and decreasing apoptosis.
【Abstract】ObjectiveTo explore the effects of p38 mitogenactivated protein kinase (MAPK) on apoptosis of small intestinal epithelial cells after transplantation in rats. MethodsSmall intestinal transplantation was performed in SD and Wistar rats. The recipients were divided into three groups: isograft group (Wistar→Wistar group), allograft group (SD→Wistar group) and allograft+cyclosporine A group (SD→Wistar+CsA group). The grafts were harvested on day 1, 3, 5 and 7 after operation. All graft samples were subjected to histological examination. The apoptosis of graft epithelial cells was detected by TUNEL method. p38 MAPK was measured by Westernblotting method and serum TNFα was determined by ELISA. ResultsMild, moderate and severe rejection reaction occurred in the SD→Wistar group, it was showed that the number of apoptotic cells increased with the severity of the rejection reaction by TUNEL. In SD→Wistar group, the numbers of apoptotic cells were significantly higher than those of the other two groups （P＜0.01）. The severity of rejection reaction in SD→Wistar+CsA group was less than that of SD→Wistar group and the number of apoptotic cells increased with the severity of the rejection reaction (P＜0.01). The level of serum TNFα varied with the apoptotic degree of small intestinal epithelial cells in SD→Wistar group and SD→Wistar+CsA group （P＜0.01）. The expression of p38 MAPK increased with the number of the apoptotic cells in SD→Wistar group and SD→Wistar+CsA group （P＜0.01）, but there was no evident change in Wistar→Wistar group （Pgt;0.05）. The expression of p38 MAPK and the level of serum TNFα were positively correlated with apoptosis in small intestinal rejection after transplantation （r=0.875， P＜0.01； r=0.837， P＜0.01）. p38 MAPK and TNFα were also positively correlated （r=0.826，P＜0.01）. ConclusionApoptosis plays an important role in small intestinal rejection. p38 MAPK is involved in apoptosis and is an important regulator in signal pathway of cell apoptosis.
ObjectiveTo study the effects and mechanism of Octreotide to inhibit the proliferation of human gastric cancer cells in vitro. MethodsHuman gastric cancer cell line SGC7901 was treated with Octreotide. Human fibroblast cell line HF and 5FU were used as control. MTT assay and fluorescent microscopy as well as flow cytometry were performed in this study. ResultsOctreotide inhibited the growth of SGC7901 in vitro within certain concentrations. The suppression was quantity dependent but did not occur when up to a certain concentration. There was no difference between Octreotide and 5FU in their inhibition on SGC7901. Octreotide had no effects on normal human fibroblast cell line HF. When SGC7901 was treated with Octreotide, the typical apoptotic bodies were identified by flow cytometry and fluorescent microscopy. ConclusionOctreotide can inhibit the proliferation of human gastric cancer cell line SGC7901 in vitro. The induction of apoptosis by Octreotide might be the primary mechanism.
Objective To investigate the mechanism of the resistance of pancreatic cancer cells to tumor necrosis factor related apoptosis inducing ligand (TRAIL)mediated apoptosis. MethodsThe expression of TRAIL receptor-4 (TRAIL-R4) in normal pancreas tissue and pancreatic cancer was analyzed by using Northern blotting, Western blotting and immunohistochemistry.ResultsTRAIL-R4 mRNA and protein were expressed at moderate to high levels in human pancreatic cancer, but demonstrated weak to negative in the normal pancreas. Moreover, pancreatic cancer cells showed b TRAIL-R4 immunostaining throughout the tumor mass. Conclusion TRAIL-R4 levels are significantly different in pancreatic cancer in comparison to the normal pancreas. These findings give new insights into the resistance mechanisms of pancreatic cancer cells towards TRAILmediated apoptosis.
ObjectiveTo observe apoptosis and proliferation of choledochus wall epithelial cell and fibrocyte, to understand the effects of apoptosis and proliferation on choledochal cyst development.MethodsThirty two cases of cystic dilatation,35 cases of cylindrical dilatation，and 25 cases of cholangiectasis caused by choledocholith were collected. All specimens were offered by department of hepatobiliarypediatric surgery. The apoptosis related index (bcl2 and bax) and cell proliferation index (PCNA) were detected by the immunohistochemical technique; Apoptosis was detected by TUNEL method. ResultsThere was serious mucosal epithelial cell damage in cystic dilatation group. In cylindrical dilatation group there was a damage similar to that of the cystis dilatation group, but the damage was not serious. In control group there was little damage in the duct wall, but there was a low positive rate of apoptosis of 〔epithelium cell (2.74±1.00)% and fibroblast (2.95±0.87）%〕, and a low bcl2 and bax’s expression rate, and a high PCNA’s expression rate 〔epithelium cell (3.74±1.00)%, fibroblast (3.71±1.77)%〕. There was no obvious difference between cylindrical dilatation group and cystic dilatation group (Pgt;0.05): the PCNA’s expression rate was low 〔(0.99±0.51)% and (0.90±0.38)% respectively〕, the bax expression rate was high in remaining epithelial cell, and the positive rate of bax was apparently higher than that of bcl2 (P＜0.05), the positive rate of the apoptosis cell was high 〔(13.94±4.77)%, (7.51±3.46)%〕; the expression rate PCNA were high 〔(9.91±2.91)%,(9.70±3.18)%〕, and expression rate of bax’s was low in the fibre tissue, the positive rate of bcl2 was markedly higher than that of bax, and the positive rate of the apoptosis cell was low 〔(3.74±2.12)%,(4.46±2.41)%〕. There were no marked difference between the two groups (Pgt;0.05). The expression of bcl2 and bax had marked difference both in cylindrical dilatation group and cystic dilatation group and as compared to control group (P＜0.05). ConclusionApoptosis has certain promoting effect in the course of choledochal cyst formation.
Objective To investigate the growth inhibition and the apoptosis inducement effects of polysaccharide of trametes robiniophila murr (PS-T) on human rectal cancer cell line HR8348 and elucidate the possible mechanisms. Methods After treatment with PS-T, the growth inhibition rate of human rectal cancer cell strain HR8348 was studied by MTT method. The apoptotic index was detected by methyl green and pyronine Y staining and by terminal deoxynucleotidyl transferase(TdT) mediated dUTP nick end labeling (TUNEL). The bcl-2, bcl-xl, bax, bak and p53 gene expressions of HR8348 cells were examined by immunohistochemical method.Results PS-T induced a dosedependent inhibition of HR8348 cells in vitro. The maximum percentage of growth inhibition was 71.1% by 36 h after administration of PS-T at a concentration of 4.0 mg/ml. There was no significant difference in the inhibitory rate as compared to the positive control (5-FU 10 μg/ml, P gt;0.05). The typical apoptosis phenomenons were observed under the light microscope by both staining methods. The apoptotic index increased parallelling with the increase of concentration of PS-T. When the PS-T concentration was 4.0 mg/ml, the apoptotic index determined by methyl green and pyronine Y staining and by TUNEL method increased rapidly to 0.1620±0.0128 and 0.2612±0.0158, respectively, which was greater than that of the positive control (5-FU 10 μg/ml, Plt;0.05). The expression of bcl-2, bcl-xl, bak and p53 was increased in the PS-Ttreated HR8348 cells by 36 h, while the bax remained unchanged. Expression index of bak/bcl-2 and bak/bcl-xl was increased significantly as compared with the control (Plt;0.05). Conclusion PS-T can significantly inhibit growth and induce apoptosis of human rectal cancer cell strain HR8348 in vitro. The apoptosis induced by PS-T might be related to the increase of the ratio of bak to bcl-2 and to bcl-xl and upregulation of the expression of p53 gene.
Objective To study the effect of 5-fluorouracil (5-FU) induced apoptosis of the rectal carcinoma cell line HR8348 in vitro and the relationship between apoptosis induced by 5-FU and the expression of bcl-2，bcl-xl，bax and p53,and to investigate the possible mechanism of apoptosis of rectal carcinoma cell line HR8348 induced by 5-FU.Methods After treatment with 5-FU for 24 h,the apoptotic index was detected by methyl green and pyronine Y staining and by terminal deoxynucleotidyl transferase (TdT)mediated dUTP nick end labeling (TUNEL).The bcl-2,bcl-xl,bax and p53 gene expression of HR8348 cells were examined by immunohistochemical method.Results After treatment with 5-FU,the apoptotic index of experiment group was significantly increased,there was significant difference as compared with the control.Exposed to 5-FU for 12 h,24 h and 36 h,the expression of bcl-2 of HR8348 cell line remained unchanged,but the expression of bcl-xl slightly diminished,while the expression of bax was remarkly increased,the expression of p53 was not detected in both experiment and control groups.Conclusion This results indicate that 5-FU may induce apoptosis of rectal carcinoma cell line HR8348 and the possible mechanism of apoptosis induction is through upregulation of bax expression and the change of bax to bcl-xl ratio.
Objective To investigate the mechanism of dexamethasone in the treatment of acute necrotizing pancreatitis (ANP). Methods The ANP of 48 SD rats were induced by retrograde infusion of sodium taurocholate through biliopancreatic duct.After 30 minutes,the therapy group was administrated with dexamethasone at a dose of 0.2 mg/100 g alone. The control group was administrated with the same amount of 0.9% saline solution.At fourth hour and twelfth hour,8 rats of each group were sacrificed to examine the levels of serum tumor necrosis factor-alpha(TNFα) and serum amylase,to score the degree of pancreatic necrosis and to evaluate acinar cell apoptosis by in situ hybridization by terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labeling(TUNEL). The survial period of 8 rats in each group were observed. Results In therapy group, the level of TNFα was (17.8±2.7) pg/ml and (8.5±1.6) pg/ml,the apoptosis index was （36.94±4.12）% and （ 32.79±3.31）%,the survival period was (33.4±21.5) h.While the control group with the indexes mentioned above were as follows: (53.6±18.7) pg/ml and (37.2±11.1) pg/ml ( P＜0.01),（4.37±1.24）% and （5.12±2.11）% （P＜0.01）,(14.6±5.7) h (P＜0.01) ,the histologic scoring for ANP between therapy group and control group was a significantly distinct (P＜0.01). Conclusion Dexamethasone can induce pancreatic acinar cell apoptosis in this model. Proper leves of TNFα may play an important role in regulating the apoptosis.Apoptosis can protect pancreas from necrosis in ANP.
ObjectiveTo study the expression of apoptosissuppressing gene (bcl2) and apoptosispromoting gene (bax) in colorectal cancerous tissue and transitional mucosas. MethodsColorectal cancerous tissue, transitional mucosas (3 cm from the cancerous tissue) and normal tissue were taken respectively in thirtyone cases. Immunohistochemical technique SP method was used to detect the expression in those tissues. ResultsThe positive expression rate of bcl2 protein in cancerous tissue and transitional mucosa were 64.5%and 60.0% respectively and significantly higher than that in normal tissue (P＜0.05). The positive expression rate of bcl2 protein in normal tissue was 35.0%. The positive expression rate of bax protein in cancerous tissue and transitional mucosa were 45.2%and 45.0% respectively and significantly lower than that in normal mucosa (P＜0.05). The positive expression rate of bax protein in normal tissue was 60.0%. There was no obvious difference in the positive rate of bax and bcl2 protein between cancerous tissue and transitional mucosa (Pgt;0.05). The expression rate of bax and bcl2 protein in colorectal cancer was irrelative to clinical pathological gradation and clinical stage (Pgt;0.05). ConclusionThere is over expression of bcl2 protein and low expression of bax protein in colorectal cancer and transitional mucosa. bcl2 protein and bax protein can affect the generation of colorectal cancer by participating in the regulation of apoptosis. But it is irrelative to clinical pathological gradation and clinical stage. Transitional mucosas should be viewed as precancerous lesion and resected during operation.