Correlation between expression of gastrin, somatostatin and cell apoptosis regulation gene bcl-2/bax in large intestine carcinoma

AIM: To explore the correlation between expression of somatostatin (SS), gastrin (GAS) and cell apoptosis regulation gene bcl-2/bax in large intestine carcinoma.METHODS: Sixty-two large intestine cancer tissue samples were randomly and retrospectively selected from patients with large intestine carcinoma. Immunohistochemical staining for bcl-2, bax, GAS, SS was performed according to the standard streptavidin-biotin-peroxidase (S-P) method.According to the semi-quantitative integral evaluation, SS and GAS were divided into three groups as follows. Scores1-3 were defined as the low expression group, 4-8 as the intermediate expression group, 9-16 as the high expression group. Bax and bcl-2 protein expressions in different GAS and SS expression groups of large intestine carcinoma were assessed.RESULTS: The positive expression rate of bax had a prominent difference between SS and GAS high, intermediate and low expression groups (P＜0.05, x2ss = 9.246; P＜0.05,x2GAS = 6.981). The positive expression rate of bax in SS high (80.0%, 8/10) and intermediate (76.5%, 13/17)expression groups was higher than that in low expression group (40.0%, 14/35) (P＜0.05, x2high vs low = 5.242; P＜0.05,x2middle vs low = 6.097). The positive expression rate of bax in GAS high expression group (27.3%, 3/8) was lower than that in low expression group (69.4%, 25/36) (P＜0.05,x2 = 4.594). However, bax expression in GAS intermediate expression group (46.7%, 7/15) was lower than that in low expression group, but not statistically significant. The positive expression rate of bcl-2 had a prominent difference between SS and GAS high, intermediate and low expression groups (P＜0.05, x2ss = 7.178; P＜0.05, x2GAS = 13.831). The positive expression rate of bcl-2 in GAS high (90.9%, 10/11)and intermediate (86.7%, 13/15) expression groups was higher than that in low expression group (44.4%, 16/36)(P＜0.05,x2high vs low = 5.600; P＜0.05, x2 middle vs low = 7.695).However, the positive expression rate of bcl-2 in SS high (40.0%, 4/10) and intermediate (47.1%, 8/9) expression groups was lower than that in low expression group (77.1%, 27/35)(P＜0.05, x2 high vs low = 4.710; P＜0.05, x2 middle vs low = 4.706).There was a significant positive correlation between the integral ratio of GAS to SS and the integral of bcl-2 (P＜0.01,r=0.340). However, there was a negative correlation between the integral ratio of GAS to the SS and bax the integral of (P＜0.05, r = -0.299).CONCLUSION: The regulation and control of gastrin,somatostatin in cell apoptosis of large intestine carcinoma may be directly related to the abnormal expression of bcl-2, bax.

The Relationship of Expression of bcl-2, p53, and Proliferating Cell Nuclear Antigen (PCNA) to Cell Proliferation and Apoptosis in Renal Cell Carcinoma

To investigate the relationship of bcl-2, p53, proliferating cell nuclear antigen (PCNA) to cell proliferation, apoptosis and pathological parameters, the patterns of cell growth and turnover in renal cell carcinoma (RCC), formalin-fixed and paraffin-embedded tissue blocks from 34 patients with RCC were examined. Cell proliferation activity was detected by PCNA immunostaining and the proliferation index (PI) was expressed as a percentage of the PCNA-positive cells in the tumor cells. Apoptosis was detected by terminal deoxy- nucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL), and the apoptotic index (AI) was expressed as a percentage of the TUNEL-positive cells in the tumor cells. Expressions of bcl-2 and p53 were assessed immunohistochemically. Our results showed that the PI ranged from 6.0 % to 24.0 % (median 12.3 %) and the AI from 2.0 % to 8.0 % (median 5.4 %) in RCC. The expression of the bcl-2 protein was demonstrated in 15 cases (44.1 %); the expression of the p53 protein, however, was seen in only 3 case. bcl-2 positivity was not associated with PI or AI or any pathological parameters. There were close associations between PI and tumor grade and stage, and a significant relationship between AI and the tumor grade of RCC. Our study suggests that bcl-2 positivity was not associated with PI or AI or any pathological parameters. There are close associations between PI and AI and tumor grade and stage of RCC. Active cell proliferation may be accompanied by frequent apoptosis in RCC.

Effects of Bcl-2 Gene Interference on the Apoptosis,Proliferation and Progesterone Secretion of Goose Follicular Granulosa Cells

Based on published sequences for chicken Bcl-2,three siRNAs（small interfering RNA）were designed,and expression vectors were constructed and transfected into goose granulosa cells cultured in vitro.Bcl-2 protein,apoptosis and proliferation of granulosa cells,48 h after the transf ection,were analyzed by flow cytometry,and progesterone（P）secreted into the culture medium was measured by radioimmunoassay.In addition,apoptosis and Bcl-2 protein level were assessed in untreated granulosa cells from the four largest preovulatory follicles（F1F4）,the smallest preovulatory follicles（SPF）,small yellow follicles（SYF）and atretic follicles.The highest level of Bcl-2 protein was observed in granulosa cells from SPF,and levels in cells from healthy follicles were significantly higher than those of atretic follicles（P【0.05）.Bcl-2 protein levels in cells subjected to RNAi were significantly lower than those of controls（P【0.05）,while apoptosis indices（AI）,proliferation indices（PI）and P secretion in the RNAi treatments were higher than those of controls（P【0.05）.

Silencing of Bcl-2 gene expression by siRNA transfection in- hibits the protective effect of fluvastatin against cell apoptosis in human aortic endothelial cells

Objective To study the protective effect of fluvastatin,one of the HMG-CoA reductase inhibitors (statins),against oxygen radical-induced oxidative damages in human aortic endothelial cell,and the role of Bcl-2 in this protection.Methods Human aortic endothelial cells with or without Bcl-2 siRNA transfection were subjected to 1-100 nM of fluvastatin and 100 la hydrogen peroxide for 24 hours.Bcl-2 mRNA and protein expression were measured by Taqman quantitative PCR and Western blotting.Cell apoptosis was measured by normal and fluorescent microscopy and Cell Death Detection ELISA.Results In the Bcl-2-expressed cells,fluvastatin significantly reversed hydrogen peroxide-induced microscopic apoptosis and apoptotic DNA fragmentation,which were accompanied by a markedly upregulation of Bcl-2 expression by fluvastatin.However,the endothelial protection by fluvastatin was completely lost in Bcl-2 siRNA transfected cells.Conclusion Fluvastatin protects human endothelial cells against oxygen radical-induced cell apoptosis in vitro,and this protection seemed to be mediated in a Bcl-2 dependent pathway.(J Geriatr Cardil 12008;5:33-38)

Transduction of Fas gene or Bcl-2 antisense RNA sensitizes cultured drug resistant gastric cancer cells to chemotherapeutic drugs

AIM To compare the expression level of Fas gene and Bcl-2 gene in gastric cancer cells SGC7901 and gastric cancer MDR (multidrug resistant) cells SGC7901/VCR, to transduce Fas cDNA and Bcl-2 antisense nucleic acid into SGC7901/VCR cells respectively, and to observe the expression of two genes in transfectants and non-transfectants as well as their drug sensitivity.METHODS Eukaryotic expression vector pBK-Fas cDNA and pDOR-anti Bcl-2 were constructed and transfected into SGC7901/VCR cells by lipofectamine, respectively. Northern blot and Western blot were used to detect the expression of mRNA and protein in SGC7901/VCR and SGC7901 cells and transfectants, and drug sensitivity of transfectants for VCR, CDDP and 5-FU was analyzed with MTT assay.RESULTS After gene transfection, 80 for Fas and 120 for antisense Bcl-2 drug-resistant clones were selected from 2×105 cells, transfection rate being 0.04% and 0.06%. Two clones of SGC7901 Fas/VCR cells and SGC7901 anti Bcl-2/VCR cells were randomly selected for further incubation. Hybridization results showed that the expression level of Fas mRNA and protein in SGC7901/VCR cells was much lower, but that of Bcl-2 mRNA and protein was higher than that in SGC7901 cells. The expression of Fas mRNA and protein in SGC7901 Fas/VCR cells was higher, and of Bcl-2 mRNA and protein was lower in SGC7901 anti Bcl-2/VCR cells than that in non-transfectants. MTT assay showed that transfectants were more sensitive to VCR, CDDP, 5-FU than non-transfectants.CONCLUSION Bcl-2 gene displayed high expression while Fas gene had low expression in drug resistant gastric cancer cells. Expression of Bcl-2 protein was effectively blocked in SGC7901 anti Bcl-2/VCR cells by gene transfection. In contrast, the expression of Fas mRNA and protein in SGC7901 Fas/VCR cells increased. Fas gene and Bcl-2 antisense nucleic acid transfection sensitized drug resistant gastric cancer cells to chemotherapeutic drugs. These results suggest cell apoptosis plays an important role in the mechanism of MDR, and enhancing apoptosis might reverse MDR.

Growth arrest-specific gene 2 suppresses hepatocarcinogenesis by intervention of cell cycle and p53-dependent apoptosis

BACKGROUND Growth arrest-specific gene 2(GAS2)plays a role in modulating in reversible growth arrest cell cycle,apoptosis,and cell survival.GAS2 protein is universally expressed in most normal tissues,particularly in the liver,but is depleted in some tumor tissues.However,the functional mechanisms of GAS2 in hepatocellular carcinoma(HCC)are not fully defined.AIM To investigate the function and mechanism of GAS2 in HCC.METHODS GAS2 expression in clinic liver and HCC specimens was analyzed by real-time PCR and western blotting.Cell proliferation was analyzed by counting,MTS,and colony formation assays.Cell cycle analysis was performed by flow cytometry.Cell apoptosis was investigated by Annexin V apoptosis assay and western blotting.RESULTS GAS2 protein expression was lower in HCC than in normal tissues.Overexpression of GAS2 inhibited the proliferation of HCC cells with wide-type p53,while knockdown of GAS2 promoted the proliferation of hepatocytes(P<0.05).Furthermore,GAS2 overexpression impeded the G1-to-S cell cycle transition and arrested more G1 cells,particularly the elevation of sub G1(P<0.01).Apoptosis induced by GAS2 was dependent on p53,which was increased by etoposide addition.The expression of p53 and apoptosis markers was further enhanced when GAS2 was upregulated,but became diminished upon downregulation of GAS2.In the clinic specimen,GAS2 was downregulated in more than 60%of HCCs.The average fold changes of GAS2 expression in tumor tissues were significantly lower than those in paired non-tumor tissues(P<0.05).CONCLUSION GAS2 plays a vital role in HCC cell proliferation and apoptosis,possibly by regulating the cell cycle and p53-dependent apoptosis pathway.

Simvastatin inhibits apoptosis of endothelial cells induced by sepsis through upregulating the expression of Bcl-2 and downregulating Bax

BACKGROUND: Many studies have showed that apoptosis of endothelial cells plays a curial role in the progress of sepsis. But the role of simvastatin in apoptosis of endothelial cells induced by sepsis is not clear. The present study aimed to investigate the role of simvastatin in apoptosis of endothelial cells induced by sepsis and its mechanism.METHODS: Human umbilical vein endothelial cells(HUVECs) were randomly divided into three groups: control group, sepsis serum intervention group(sepsis group) and simvastatin+sepsis serum intervention group(simvastatin group). After 24-hour incubation with corresponding culture medium, the relative growth rate of HUVECS in different groups was detected by MTT assay; the apoptosis of HUVECs was detected by Hoechst33258 assay and fl ow cytometry; and the expression of the Bcl-2 and Bax genes of HUVECs was detected by PCR.RESULTS: Compared with the sepsis group, HUVECs in the simvastatin group had a higher relative growth rate. Apoptotic HUVECs decreased significantly in the simvastatin group in comparison with the sepsis group. Expression of the Bcl-2 gene in HUVECs decreased obviously, but the expression of the Bax gene increased obviously after 24-hour incubation with sepsis serum; however, the expression of the Bcl-2 and Bax genes was just the opposite in the simvastatin group.CONCLUSIONS: Our study suggests that simvastatin can inhibit apoptosis of endothelial cells induced by sepsis through upregulating the expression of Bcl-2 and downregulating Bax. It may be one of the mechanisms for simvastatin to treat sepsis.

A PRELIMINARY STUDY ON SURVIVIN AND BCL-2 EXPRESSION IN CERVICAL CARCINOMAS

Objective To study the expression of a novel inhibitor of apptosis and survivin in cervical carcinoma and its relationship to the expression of Bcl-2.Methods Using SP immunohistochemical technique, we examined the expression of survivin and Bcl 2 in 59 cervical invasive squamous cell carcinomas.Results Survivin was expressed in 41 of 59 cases(69.5%) of cervical carcinomas. In contrast, no expression of survivin in normal cervical tissues was observed. Overexpression of survivin was related to the tumor grade and clinical stage. Survivin positive cases were strongly associated with Bcl 2 expression(80% versus 35.7%; P <0.005).Conclusion Apoptosis inhibition by survivin abnormal expression, alone or in cooperation with Bcl 2, may participate in the onset and progression of cervical carcinoma. Survivin is a new diagnostic/therapeutic target in cervical cancer.

Curcumin induces the expression of NF-κB and Bcl-2/Bax in human renal cell carcinoma cell line ACHN

Objective： To explore the in vitro effects of curcumin on the proliferation and apoptosis of the human renal cell carcinoma cell line ACHN, and to investigate its mechanisms of action. Methods： The human renal cell carcinoma cell line ACHN was treated with different concentrations of curcumin for 24 h. The MTT assay was used to evaluate the cytotoxic effects of curcumin and flow cytometry was utilized to observe and detect the apoptosis of ACHN cells induced by curcumin. The expression levels of Bcl-2, Bax and NF-κBP65 mRNA were evaluated by Reverse Transcription-Polymerase Chain Reaction （RT-PCR）, while the expression of Bcl- 2, Bax, NF-κBP65 and IκB proteins was evaluated by Western blot. Results： The concentrations of curcumin used significantly inhibited the proliferation of ACHN human renal cell carcinoma cells in vitro in a dose and time-dependent manner （Ftime=5.55, P 〈 0.05; Fdose=110.05, P 〈 0.05）. Obvious apoptosis of cells treated with different concentrations of curcumin could be observed by FCM. Compared with the control group, the apoptosis rates of curcumin-treated cells were markedly increased （F=96.35, P 〈 0.05）. Lower dose of curcumin significantly induced the apoptosis of ACHN cells. With intervention of different concentrations of curcumin （0, 10, 20 and 40 μmol/L） for 24 h, the expression levels of Bcl-2 and NF-κBP65 mRNA in ACHN cells were decreased while the expression level of Bax mRNA was increased （P 〈 0.05）, and Bcl-2, and NF-κBP65 protein decreased, while Bax and IκB protein increased compared with those in the untreated group. Conclusion： Curcumin inhibited proliferation and increased apoptosis of the human renal cell carcinoma cell line ACHN. These curcumin effects appear to involve up-regulating IκB, down-regulating NF-κB, and regulating the expression of the apoptosis genes Bcl-2/Bax.

THE EXPRESSION OF BCL-2 AND BAX PROTEINS IN GASTRIC CARCINOMA AND PRECANCEROUS LESIONS

Objective To investigate the variance of expression of bcl-2 and bax genes in the genesis or gastric carcinoma as well as their relationship. Methods Thirty-five cases of early-stage gastric carcinoma and Twenty-four cases ot chronic atrophic gastritis were studied by immunohistochemical method. Results There were no statistical differences of bcl-2 expression levels between gastric carcinoma and atypical hyperplasia or paracancerous intestinal- epithelial metaplasia(IEM) (P>0.05).There were statistical differences of bcl-2 expression between normal epithe- lial tissues (or non-cancerous IEM) and the other three groups(P<0.05), but no statistical difference between the normal epithelial and the non-cancerous IEM group was observed(P>0.05). The expressions or bax protein were found in the normal epithelial and the other groups in varying degrees,but there were no statistical differences be- tween either two of the groups (P>0.05). The bcl-2/bax ratio was higher in early-stage gastric carcinoma,atypical hy- perplasia and paracancerous intestinal-metaplasia than in the non-cancerous intestinal-metaplasia (P<0.05) and nor- mal epithelial tissues(P<0.01). Conclusion The abnormal expression of bcl-2 protein and bax protein,especially the increased bcl-2/bax ratio, probably play an important role in the course of carcinogenesis or gastric carcinoma.

Detection of apoptotic cells and immunohistochemical study of bcl-2 and p53 gene protein in primary gastric mucosa-associated lymphoid tissue (MALT) lymphoma

To identify the apoptotic cells in gastric MALT lymphoma and its relationship between bcl-2 and p53 gene expression. Methods: TdT-mediated dUTP biotin Nick End labeling (TUNEL) and immuno-histochemistry ABC method were used to display apoptotic cells and the gene protein expression of bcl-2 and p53 independently. Results: Apoptotic indices (AI) in high-grade MALT lymphomas were significantly higher than in mixed-grade group and low-grade group (P<0.05). Bcl-2 was expressed in 83% of low-grade tumors, 61.6% of the median-grade tumors and 43.7% of high-grade tumors. An inverse correlation was observed between the expression of bcl-2 and apoptotic indices. Only 27 cases were p53 positive. The frequency of p53 positivity was significantly increased as the histologic grade advanced (P<0.05). There was also an inverse correlation between the expression of bcl-2 and p53. Conclusion: Apoptosis may be important in tumors development and transmission. p53 and bcl-2 were important regulatory genes of apoptosis and may be associated with transformation from low- grade to high-grade lymphomas.

PTEN基因诱导人脑胶质瘤SHG-44细胞凋亡及bcl-2蛋白表达下调

目的 探讨PTEN基因对人脑胶质瘤SHG 44细胞凋亡及凋亡相关基因bcl 2表达的影响 ,阐明PTEN基因抑制肿瘤细胞增殖的机理。方法 PTEN基因体外转染SHG 44细胞 ,筛选阳性细胞克隆 ,以原位杂交、免疫组化方法检测PTEN基因的表达情况采用透射电镜、流式细胞仪和核DNA琼脂糖凝胶电泳检测细胞的凋亡情况以免疫荧光法检测bcl 2基因的表达。结果 PTEN基因转染的SHG 44细胞有PTEN基因和蛋白的表达。透射电镜下可见转染PTEN基因后细胞核染色质浓缩边集、胞浆浓缩、核碎裂及凋亡小体形成等典型的凋亡表现 ;流式细胞仪示细胞周期从G1 期到S期发生抑制 ,并且在G1 期峰前出现一明显的凋亡峰 (1 2 .9% ) ;细胞核DNA琼脂糖凝胶电泳呈现凋亡细胞特有的梯状条带 ;bcl 2的表达也显著下调。转染空载体和未转染的SHG 44细胞无明显的凋亡表现。结论 PTEN基因可诱导SHG 44细胞凋亡 ,并下调bcl 2蛋白的表达 。

碘对大鼠甲状腺细胞凋亡及bax、bcl-2基因mRNA表达的影响

目的探讨碘对甲状腺细胞凋亡及凋亡相关基因表达的影响。方法Wistar大鼠分为6组,即低碘组(LI)、正常碘组(NI)、5倍碘组(5HI)、10倍碘组(10HI)、50倍碘组(50HI)、100倍碘组(100HI),用含不同碘的自来水喂养,6个月后取甲状腺。末端标记法(TUNEL)进行原位细胞凋亡检测,反转录-聚合酶链反应(RT-PCR)法对甲状腺细胞凋亡相关基因bax、bcl-2进行半定量测定。结果原位细胞凋亡检测结果表明,LI组细胞凋亡明显,而NI组与其他组均未见凋亡细胞。baxmRNA表达水平以bax/β-actin光密度比表示,LI组为1.096±0.089,NI组为0.647±0.062,5HI组为0.638±0.191,10HI组为0.676±0.081,50HI组为0.644±0.092,100HI组为0.751±0.152;同样方法表示,bcl-2mRNA表达水平分别为0.273±0.185、0.172±0.115、0.236±0.107、0.235±0.071、0.267±0.065、0.313±0.062。结果表明,在LI组大鼠甲状腺bax、bcl-2mRNA表达水平均明显增加(P<0.05);在其他组,bcl-2mRNA表达水平随给碘量增加而增加,而bax无明显变化。但bax/bcl-2比值随摄入碘量增加而呈降低趋势。结论碘缺乏易诱发大鼠甲状腺细胞凋亡;而碘过量不易引起细胞凋亡,甲状腺细胞对碘过量有一定耐受能力。bcl-2家族参与甲状腺细胞凋亡过程。

盐酸右美托咪定预处理对缺血-再灌注损伤大鼠心肌Bax和Bcl-2表达的影响

目的研究盐酸右美托咪定对大鼠心肌缺血-再灌注损伤时心肌凋亡相关基因Bax和Bcl-2表达的影响。方法将21只健康SD大鼠随机分为3组:假手术组(sham组,n=7)、缺血-再灌注组(I/R组,n=7)、缺血-再灌注+盐酸右美托咪定组(DEX组,n=7)。采用结扎左冠状动脉前降支的方法制备在体大鼠心肌缺血-再灌注损伤模型。采用RT-PCR、免疫组化方法检测Bcl-2和Bax mRNA、蛋白的表达,TUNEL法检测凋亡细胞TTC染色测定心肌梗死面积。结果与sham组比较,I/R组Bcl-2和Bax mRNA和蛋白表达增加(P<0.05);与I/R组比较,DEX组Bcl-2mRNA和蛋白表达升高(P<0.05),Bax mRNA和蛋白表达下降(P<0.05),凋亡细胞明显减少(P<0.01),心肌梗死面积减小(P<0.05)。结论盐酸右美托咪定预处理可上调心肌缺血-再灌注损伤大鼠心肌Bcl-2mRNA和蛋白表达,下调Bax mRNA和蛋白表达,表明盐酸右美托咪定在心肌缺血-再灌注损伤中有抗凋亡的作用。

电针对大鼠脑缺血再灌注损伤后细胞凋亡相关基因Bcl-2、Bax表达的影响

目的探讨电针对脑缺血再灌注大鼠皮质细胞凋亡相关蛋白Bcl-2、Bax及其mRNA表达的影响。方法雄性清洁级SD大鼠72只,采用随机数字表法分为假手术组、模型组和电针组各24只。用改良Longa线栓法制作大鼠右侧大脑中动脉脑缺血模型,缺血2 h,于再灌注开始后电针组针刺"百会"和"大椎"穴。各组于缺血再灌注24 h后行神经行为学评分和脑含水量测定,免疫组化染色法检测缺损侧皮层组织Bcl-2、Bax的蛋白表达,qRT-PCR检测Bcl-2 mRNA、Bax mRNA表达的变化。结果模型组、电针组神经行为学评分均低于假手术组(P<0.01),与模型组比较,电针组的神经行为学评分升高(P<0.05)。与假手术组比较,模型组脑含水量明显增高(P<0.01),电针组的差异无统计学意义(P>0.05),较之模型组,电针组的脑含水量显蓍降低(P<0.01)。与假手术组比较,模型组、电针组Bcl-2蛋白及mRNA的表达均显著增多(P<0.05或P<0.01),电针组又高于模型组(P<0.05);较之假手术组,模型组Bax蛋白及mRNA表达显著上升(P<0.01),电针组无明显差异(P>0.05),电针组较模型组显著降低(P<0.01);Bcl-2/Bax及Bcl-2 mRNA/Baxm RNA的比值,模型组降低而电针组升高(P<0.01)。结论电针可以通过提升Bcl-2/Bax的比值使抗凋亡基因占据优势,从而抑制缺血再灌注区的细胞凋亡,减轻脑水肿,促进神经功能恢复。

miR-204通过下调Bcl-2和Sirt1表达抑制肝癌细胞生长

目的探讨微小RNA 204(miR-204)在肝细胞癌中的表达、临床意义及可能分子机制。方法收集手术切除的60例肝细胞癌及对应癌旁肝组织,实时定量PCR(qRT-PCR)检测miR-204在肝癌及癌旁组织中的表达,免疫组织化学染色检测miR-204下游潜在靶点Bcl-2与组蛋白脱乙酰酶1(Sirt1)的表达;用人工合成的miR-204模拟物转染人SMMC-7721肝癌细胞,MTT法及流式细胞术检测SMMC-7721细胞的增殖、凋亡的情况,qRT-PCR、Western blot法分别检测Bcl-2与Sirt1的mRNA和蛋白表达。结果 miR-204在肝癌组织中表达水平显著低于对应癌旁组织;肝癌组织中miR-204低表达与肿瘤大小、肿瘤个数、肿瘤TNM分期显著相关;miR-204低表达组Bcl-2与Sirt1蛋白表达显著高于miR-204高表达组,相关性分析结果显示肝癌组织中miR-204与Bcl-2、Sirt1蛋白表达呈显著负相关;miR-204可显著抑制SMMC-7721细胞的增殖并促进其凋亡,并下调Bcl-2与Sirt1的mRNA与蛋白表达水平。结论 miR-204在肝癌组织中表达下调并与肝癌恶性临床病理特征有关,miR-204抑制肝癌细胞增殖、促进其凋亡的作用可能与下调Bcl-2和Sirt1表达有关。

米非司酮对人早孕期蜕膜细胞凋亡及其调控基因bcl-2/bax的影响

目的 :探讨米非司酮对早孕期蜕膜组织细胞bcl 2 /bax的影响及与妊娠终止的关系。方法 :用琼脂糖凝胶电泳、TUNEL法检测凋亡的发生及凋亡细胞的定位 ,用免疫组化法检测bcl 2 /bax蛋白的表达和相互关系。结果 :(1)正常早孕 4 0 + 天蜕膜组织细胞大量凋亡 ,bcl 2蛋白表达量较低 ,bax蛋白有较强表达 ;(2 )正常早孕 5 0 + 天 ,凋亡细胞明显减少 ,bcl 2的表达显著增强 ,bax蛋白表达减弱 ;(3)早孕 5 0 + 天应用米非司酮 ,蜕膜组织出现大量凋亡细胞及明显凋亡带 ,bcl 2蛋白表达明显降低 ,bax蛋白表达较前明显增强。结论 :早孕期米非司酮流产的机制可能与蜕膜组织细胞凋亡异常相关 ,bcl 2 /bax途径可能是其诱导早孕期蜕膜细胞凋亡的重要因素。

靶向Bcl-2、Bcl-xl、Mcl-1、Bcl-w、A1反义核酸抑制消化系肿瘤细胞增殖效果的差异

目的比较靶向Bcl-2、Bcl-xl、Mcl-1、Bcl-w、A1反义核酸(antisense oligodeoxynucleotide,ASO)对消化系统肿瘤细胞(肝癌HepG2细胞、胃癌MGC-803细胞、结肠癌Lovo细胞)的增殖抑制作用和致凋亡作用的差异。方法分别合成靶向Bcl-2、Bcl-xl、Mcl-1、Bcl-w、A1的反义核酸和随机序列反义核酸(randomolig odeoxynucleotide,RODN),采用脂质体Li-pofectamineTM 2000转染细胞,WST法检测相同浓度的5种ASOs对肝癌HepG2细胞、胃癌MGC-803细胞、结肠癌Lovo细胞的增殖抑制作用和致凋亡作用。结果 Bcl-2、Bcl-xl、Mcl-1、Bcl-w、A1等5种ASOs中,不论是对细胞增殖抑制还是致凋亡作用,均以Bcl-xlASO、Mcl-1ASO的作用效果较好。结论在Bcl-2、Bcl-xl、Mcl-1、Bcl-w、A1等5种ASOs中,Bcl-xlASO、Mcl-1ASO可明显抑制消化系肿瘤细胞增殖,诱导细胞凋亡。

Bax-Bcl-2异源二聚体与胃癌细胞凋亡的关系

目的：明确Bax-Bcl-2异源二聚体与NSAIDs诱导胃癌细胞凋亡的关系。方法：以NSAIDs诱导胃癌细胞凋亡,并通过丫啶橙(AO)染色、共聚焦显微镜、流式细胞术、TUNEL法加以证实。应用Western blot方法检测Bax、Bcl-2蛋白的表达,应用免疫沉淀-蛋白印迹法检测Bax-Bcl-2异源二聚体水平的改变。结果：NSAIDs药物吲哚美辛(indomethacin,indo)800 mmol/L和阿司匹林(aspirin,Asp)8 mmol/L作用24 h后,AGS细胞发生显著的凋亡(Indo 800 mmol/L作用24 h凋亡率(9．34±1．99)%,48 h(38．97±3．36)%,Asp 8 mmol/L 48 h凋亡率(17．60±3．30)%。随着药物作用时间的延长,Bax-Bcl-2异源二聚体水平逐渐增高,在6～48 h内均呈现增强趋势,Bax蛋白表达的增强在6～24 h最为明显,Bcl-2蛋白未检测到。结论：NSAIDs可诱导胃癌细胞AGS凋亡；Bax-Bcl-2异源二聚体可能具有促进细胞凋亡的作用,也可能是NSAIDs调控肿瘤细胞凋亡的一个重要作用点。

川芎嗪对缺血/再灌注损伤大鼠肾脏细胞凋亡及Bcl-2和Bax表达的影响

目的:观察川芎嗪对急性缺血/再灌注(I/R)损伤大鼠肾脏细胞凋亡及凋亡相关蛋白的影响,探讨川芎嗪对急性肾I/R损伤保护作用的可能机制.方法:将40只Wistar大鼠夹闭双侧肾动脉45min再灌注24h,制备成急性肾I/R损伤动物模型,随机分为假手术对照组、I/R组、川芎嗪治疗组和川芎嗪预防组,采用原位末端标记法检测细胞凋亡指数,免疫组化法测定Bcl-2,Bax表达,电镜观察肾组织细胞超微结构.结果:I/R组较假手术对照组肾小管细胞凋亡指数明显增多(28.8±4.6vs1.9±0.5,P<0.01),Bax表达显著增强(162.6±17.1vs182.7±12.8,P<0.01),Bcl-2/Bax显著降低(1.1±0.1vs1.0±0.1,P<0.01);川芎嗪预防组较I/R组肾小管凋亡细胞数明显减少(13.6±2.9vs28.8±4.6,P<0.05),Bax表达明显减弱(179.1±12.7vs162.6±17.1,P<0.05),Bcl-2表达明显增强(166.6±15.1vs178.7±13.0,P<0.05),Bcl-2/Bax显著增高(0.9±0.1vs1.1±0.1,P<0.05).结论:川芎嗪对急性肾I/R损伤具有保护作用,其作用机制可能是通过调节凋亡相关基因Bcl-2和Bax介导的I/R损伤肾脏细胞凋亡而实现.