Stromal cell-derived factor 1alpha stimulates human endometrial carcinoma cell growth through the activation of both extracellular signal-regulated kinase 1/2 and Akt

OBJECTIVE: The aim of study was to investigate the proliferative effects of stromal cell-derived factor-1alpha (SDF-1alpha) on endometrial carcinomas cell lines with different estrogen receptors (ER) and PTEN protein profiles. METHODS: MTT assays was used to detect the proliferation of HEC-1A and Ishikawa cells, and Western blotted analysis was used to detect activation of Akt and ERK1/2 in both cell lines after exposure to various concentrations of SDF-1alpha, MAPK-specific inhibitor PD98059 or PI3K-specific inhibitor LY294002. RESULTS: Low concentrations of SDF-1alpha (50 ng/ml) induced proliferation in both cell lines. ERK1/2 was significantly activated for more than 2 h by SDF-1alpha at 20 ng/ml in HEC-1A cells, but not in Ishikawa cells. In contrast, Akt was significantly activated for over 2 h in Ishikawa cells but remained unchanged in HEC-1A cells. High concentrations of SDF-1alpha activated Akt and ERK1/2 pathways in both cell lines in a dose-dependent manner, which was primarily inhibited by LY294002 for pAkt and by PD98059 for pERK 1/2. CONCLUSIONS: SDF-1alpha could stimulate the cell proliferation of endometrial carcinoma with different expression status of ER and PTEN in vitro, likely through the activation of both Akt and ERK1/2 signaling pathways.     

抑制PI3K/Akt信号通路拮抗胰岛素诱导的子宫内膜癌细胞增殖

目的:研究抑制磷脂酰肌醇3激酶(PI3K)/Akt信号通路对胰岛素诱导的子宫内膜癌细胞增殖的拮抗作用。方法:将无血清饥饿的子宫内膜癌Ishikawa3-H-12细胞分为空白对照组、10-6mol/L胰岛素单独刺激组以及不同剂量PI3K抑制剂-LY294002预处理后再用胰岛素刺激组。Western blot检测各组Akt磷酸化(p-Akt)水平,MTT试验观察细胞增殖情况。结果:胰岛素可引起内膜癌细胞Akt活化,刺激15min后p-Akt/Akt比值显著高于空白对照组(68.68%vs 26.21%,P<0.001)。LY294002以浓度依赖方式抑制胰岛素引起的Akt磷酸化。MTT试验显示,在药物处理24h,48h和72h 3个时间点,不同组别570nm吸光度值(OD570nm)均有显著差异(F=156.329,700.973,812.224,均P<0.001)。胰岛素组OD570nm值均高于同时间点的空白对照组(均P<0.001),胰岛素促内膜癌细胞增殖作用于48h时最为显著。LY294002可抑制胰岛素的增殖促进作用,此抑制作用具有浓度依赖性。不同剂量LY294002抑制作用的时间依赖性不同,48h时小剂量(0.1、1、10μmol/L)的抑制作用最为显著,72h时胰岛素重新呈现一定的促增殖作用;而50μmol/L LY294002可以持久抑制胰岛素的促增殖作用。结论:PI3K抑制剂LY294002可以通过抑制Akt磷酸化阻断胰岛素信号传导,拮抗后者促子宫内膜癌细胞增殖的作用。     

Induction of apoptosis and inhibition of telomerase activity by arsenic trioxide (As2O3) in endometrial carcinoma cells

OBJECTIVES: To examine the effects of arsenic trioxide (As2O3) on human endometrial carcinoma cell lines with respect to cytotoxicity and the induction of apoptosis and telomerase expression in vitro. METHODS: Four endometrial carcinoma cell lines (Ishikawa, ECC-1, RL-95-2 and Hec-1B) were treated with increasing concentrations of As2O3. RESULTS: As2O3 inhibited proliferation of all cell lines in a concentration and time-dependent manner (IC50 range of 3-7 microM). Coincident with the inhibition of growth, As2O3 also induced apoptosis in all cell lines as measured by the time-dependent increase in M30 antibody fluorescence (binds a caspase-cleaved epitope of cytokeratin 18) detected by flow cytometry, and reduced telomerase activity by decreasing the hTERT mRNA expression. CONCLUSION: As2O3 may exert anti-tumor effects through the induction of the apoptosis pathway and telomerase and hTERT may play an important role in the anti-apoptotic effects which are observed when endometrial cancer cells are treated in vitro with As2O3.     

Mitogenic and anti-apoptotic effects of insulin in endometrial cancer are phosphatidylinositol 3-kinase/Akt dependent

Objective

To determine serum insulin levels, expression and phosphorylation of InsR, IRS-1 and Akt in endometrial cancer (EC) tissues, and to explore the correlation between them. To investigate if insulin-induced mitogenic and anti-apoptotic effects are PI3K-dependent in EC cells.

Methods

Serum insulin levels were measured by radioimmunoassay. We performed RT-PCR and western blotting to evaluate the expression and activation of key proteins of PI3K/Akt pathway in 63 EC tissues. The proliferation and apoptosis rates were determined with MTT, BrdU and annexin V/PI assays.

Results

Serum insulin levels and InsR, IRS-1 and Akt expression and phosphorylation were significantly elevated in patients with EC compared to those without EC. Additionally, levels of p-InsR, p-IRS-1, and p-Akt were significantly higher in patients with high-grade, advanced stage, deep myometrial invasion, and lymph-node metastasis. The expression and activation of InsR, IRS-1, and p-Akt were positively related with the levels of serum insulin. The insulin-induced mitogenic and anti-apoptotic effects in EC cells were blocked when cells were pre-incubated with LY294002. Ishikawa 3-H-12 cells showed increased p-Akt levels after treatment with insulin at 10^− 8 M for 15 min. The insulin-induced Akt activation was inhibited by LY294002 in a dose-dependent manner.

Conclusion

Insulin played an essential role in EC tumorigenesis. Activation of InsR, IRS-1, and Akt was associated with features of aggressive EC. Insulin was a mitogenic and anti-apoptotic agent for EC cells, and these effects were dependent on PI3K/Akt pathway. Decreasing insulin level and blocking the InsR-IRS-PI3K-Akt pathway could be viable preventive and therapeutic strategies for EC.     

The telomerase activity and expression of hTERT gene can serve as indicators in the anti-cancer treatment of human ovarian cancer

OBJECTIVE: The aim of this study was to evaluate the clinicopathological significance of telomerase activity and expression of hTERT gene in human ovarian cancer. The potential value of them as indicators for chemotherapy in ovarian cancer cells was also studied. MATERIALS AND METHODS: A total of 73 samples and ovarian cancer cell lines HO-8910 and COC1 were studied. Telomerase activity was detected by PCR-TRAP-ELISA assay and the expression of the hTERT mRNA was analyzed by semi-quantitative RT-PCR. Alteration of the telomerase activity and hTERT mRNA were also analyzed in the ovarian cancer cells treated with different concentration and different time of cisplatin. Cytogenetic analysis was performed to compare the telomere status in the OH-8910 cells pre- and post-cisplatin treatment. The associations between these two markers and cisplatin induced-apoptosis were respectively analyzed in COC1 cells by the flow cytometry. RESULTS: Telomerase activity are highly increased in malignancy (0.795+/-0.168(A450-655 nm)) than borderline (0.389+/-0.174(A450-655 nm)), benign tumors (0.236+/-0.102(A450-655 nm)) and normal ovary (0.213+/-0.070(A450-655 nm)) (p < 0.05). Twenty samples showed detectable levels of hTERT. The hTERT gene positive lesion showed significantly higher telomerase activity than negative (p = 0.004). There is a significant correlation between the telomerase activity and expression of hTERT (r = 0.921). Both telomerase activity and expression of hTERT can reflect the chemotherapeutic effect of cisplatin in a time-dependent and dose-dependent manner. Treatment with 10 microM cisplatin, the hTERT mRNA decreased after 12h and completely disappeared after 48 h, whereas the telomerase activity did not decrease until 24h. Results from cytogenetic analysis and flow cytometry assay confirmed that the alterations of these two markers are associated with the anti-cancer treatment of cisplatin. CONCLUSION: Expression of hTERT gene is rate-limiting with the activation of telomerase. Both of they may be useful in the predicting of chemotherapeutic effect in ovarian cancer.     

17β-雌二醇对子宫内膜癌细胞磷脂酰肌醇3激酶/蛋白激酶B信号传导通路的激活作用

目的　探讨 17β 雌二醇 (E2 )对子宫内膜癌细胞系Ishikawa细胞磷脂酰肌醇 3激酶 /蛋白激酶B(PI 3K/PKB)信号传导通路的激活作用以及PI 3K抑制剂对其的影响。方法　应用免疫印迹杂交技术 ,检测一定浓度 (1× 10 -6mol/L) 17β E2 作用于Ishikawa细胞不同时间 (分别为 0、5、15、30、6 0、12 0min)后和不同浓度 (分别为 0、1× 10 -10 、1× 10 -8、1× 10 -6、1× 10 -4mol/L) 17β E2 作用Ishikawa细胞一定时间 (30min)后PKB的活化情况 [以磷酸化PKB和总PKB比值 (p PKB/PKB)表示 ],以及用同法检测PI 3K抑制剂LY2 94 0 0 2对 17β E2 活化PKB的影响。结果　 1× 10 -6mol/L 17β E2 作用于Ishikawa细胞 15min时 ,PKB的活化水平 (0 5 33± 0 0 2 9)已明显高于对照 (0 36 1± 0 0 2 9,P <0 0 5 ) ,30min时最明显 (0 6 6 6± 0 0 2 1,P <0 0 0 1) ,而且持续至少达 12 0min时 ;随着 17β E2 浓度 (分别为 1× 10 -10 、1×10 -8、1× 10 -6、1× 10 -4mol/L)的增加 ,PKB的活化水平逐渐增高 ,与对照比较 ,差异有显著性 (除 1×10 -10 mol/L外 ,P值分别为 >0 0 5、<0 0 5、<0 0 5、<0 0 0 1)。随着LY2 94 0 0 2作用浓度 (分别为 0 1、10、5 0、10 0 μmol/L)的增加 ,17β E2 作用Ishikawa细胞后P     

Metformin potentiates the effects of paclitaxel in endometrial cancer cells through inhibition of cell proliferation and modulation of the mTOR pathway

Objectives

To examine the effects of combination therapy with metformin and paclitaxel in endometrial cancer cell lines.

Methods

ECC-1 and Ishikawa endometrial cancer cell lines were used. Cell proliferation was assessed after exposure to paclitaxel and metformin. Cell cycle progression was assessed by flow cytometry. hTERT expression was determined by real-time RT-PCR. Western immunoblotting was performed to determine the effect of metformin/paclitaxel on the mTOR pathway.

Results

Paclitaxel inhibited proliferation in a dose-dependent manner in both cell lines with IC₅₀ values of 1-5 nM and 5-10 nM for Ishikawa and ECC-1 cells, respectively. Simultaneous exposure of cells to various doses of paclitaxel in combination with metformin (0.5 mM) resulted in a significant synergistic anti-proliferative effect in both cell lines (Combination Index < 1). Metformin induced G1 arrest in both cell lines. Paclitaxel alone or in combination with metformin resulted in predominantly G2 arrest. Metformin decreased hTERT mRNA expression while paclitaxel alone had no effect on telomerase activity. Metformin stimulated AMPK phosphorylation and decreased phosphorylation of the S6 protein. In contrast, paclitaxel inhibited AMPK phosphorylation in the ECC-1 cell line and induced phosphorylation of S6 in both cell lines. Treatment with metformin and paclitaxel resulted in decreased phosphorylation of S6 in both cell lines but only had an additive effect on AMPK phosphorylation in the ECC-1 cell line.

Conclusions

Metformin potentiates the effects of paclitaxel in endometrial cancer cells through inhibition of cell proliferation and modulation of the mTOR pathway. This combination may be a promising targeted therapy for endometrial cancer.     

促性腺激素释放激素Ⅰ型激动剂和Ⅱ型对不同PTEN基因表达状态子宫内膜癌细胞的作用

目的 探讨促性腺激素释放激素Ⅰ型(GnRH-Ⅰ)激动剂--曲普瑞林和GnRH-Ⅱ对不同PTEN基因表达状态的子宫内膜癌细胞的作用.方法 不同浓度(10-11、10-9、10-7、10-5mol/L)的曲普瑞林和GnRH-Ⅱ分别作用于不同PTEN基因表达状态的3种子宫内膜癌细胞细胞系Ishikawa [PTEN基因表达阴性(-)]、Ishikawa-PTEN[PTEN基因表达阳性(+)]、Ishikawa-neo[PTEN(-)]细胞后,应用四甲基偶氮唑蓝比色法、碘化丙啶染色流式细胞计数法、膜联蛋白染色流式细胞术检测内膜癌细胞增殖、细胞周期和细胞凋亡的变化;蛋白印迹法检测内膜癌细胞中蛋白激酶B(Akt)及细胞外信号调节激酶1/2(ERK1/2)的活化情况.在曲普瑞林和GnRH-Ⅱ作用的基础上,使用17β雌二醇(17β-E2,10-8mol/L)和雌激素受体拮抗剂--ICI182780(10-6mol/L)分别进行干预,再次检测上述指标的变化.结果 不同浓度(10-11、10-9、10-7、10-5mol/L)的曲普瑞林及GnRH-Ⅱ作用后,3种细胞的增殖明显受到抑制(P<0.01);细胞凋亡率明显增加(P<0.01或P<0.05);细胞生长减慢,G0/G1期细胞比例增多,G2/M期和S期细胞比例减少;上述作用均呈明显浓度依赖关系(P<0.01或P<0.05).曲普瑞林及GnRH-Ⅱ均可明显抑制Ishikawa、Ishikawa-neo细胞中Akt和ERK1/2的活化(P<0.01);而对Ishikawa-PTEN细胞中Akt和ERK1/2的活化无明显抑制作用(P<0.05).17β-E2可明显拮抗曲普瑞林和GnRH-Ⅱ的上述作用(P<0.01或P<0.05).结论 曲普瑞林和GnRH-Ⅱ可通过抑制Akt和ERK1/2的活化,促进子宫内膜癌细胞凋亡,并抑制细胞增殖,此作用呈明显浓度依赖关系,并与PTEN基因表达状态有关,且可被17β-E2拮抗.提示GnRH-Ⅰ激动剂可用于低雌激素表达子宫内膜癌患者的个体化内分泌治疗.     

双酚A激活PI3K/AKT通路促进子宫内膜癌细胞增殖的研究

目的:研究双酚A(bisphenol A,BPA)活化磷脂酰肌醇3激酶/蛋白激酶B(PI3K/AKT)促子宫内膜癌细胞Ishikawa和RL952增殖的机制。方法:CCK8试剂盒检测Ishikawa和RL952细胞的增殖情况,蛋白质印迹(Western blotting)法检测p-AKT蛋白的表达。结果:在Ishikawa和RL952细胞中,BPA作用48 h时,细胞增殖呈浓度依赖性,1μmol/L的BPA促细胞生长效应最显著,Ishikawa和RL952细胞增殖率分别为0.758±0.023和0.692±0.042。BPA浓度超过1μmol/L后,促细胞增殖的作用下降。BPA作用24 h时促增殖效应不明显,BPA作用72 h时表现出细胞毒作用。1μmol/L BPA处理的Ishikawa和RL952细胞48 h后p-AKT蛋白的表达较对照组升高(P<0.05),加入PI3K抑制剂(LY294002),p-AKT的蛋白表达比对照组降低,但差异无统计学意义(P>0.05)。结论:BPA通过激活PI3K/AKT通路促进子宫内膜癌细胞增殖。     

信号传导通路抑制剂PD98059和LY294002对子宫内膜癌细胞和裸鼠移植瘤的抑制作用

目的 观察有丝分裂原活化蛋白激酶(MAPK)信号传导通路抑制剂PD98059和磷脂酰肌醇3激酶(PI3K)信号传导通路抑制剂LY294002对子宫内膜癌细胞株Ishikawa细胞和子宫内膜癌裸鼠移植瘤的抑制作用.方法 (1)体外实验:实验分为4组,即PD组(加入浓度分别为0、1、50、100 μmol/L的PD98059)、LY组(加入浓度分别为0、1、50、100 μmol/L的LY294002)、PD+LY组(加入浓度均为50 μmol/L的PD98059和LY294002)、对照组[仅加入二甲基亚砜(DMSO)],分别培养24、48和72 h.应用四甲基偶氮唑蓝(MTT)比色法检测各组Ishikawa细胞的增殖情况,流式细胞仪检测各组Ishikawa细胞的细胞周期比例和细胞凋亡率.(2)体内实验:建立子宫内膜癌裸鼠移植瘤模型,随机分为4组(每组6只):PD组(注射PD98059 50 mg/kg)、LY组(注射LY294002 50 mg/kg)、PD+LY组(注射PD98059 50 mg/kg和LY294002 50 mg/kg)、对照组(注射等量的生理盐水),每周2次,共3周;观察移植瘤的生长情况,并计算抑瘤率;用末端脱氧核苷酸转移酶介导的脱氧尿苷三磷酸标记(TUNEL)法检测移植瘤组织的细胞凋亡情况,以细胞凋亡指数表示;免疫组化法检测移植瘤组织内磷酸化细胞外信号调节激酶(p-ERK)和磷酸化蛋白激酶B(p-Akt)蛋白的表达.结果 (1)PD98059和(或)LY294002处理后,PD组、LY组Ishikawa细胞增殖的抑制作用均呈明显的时间和浓度依赖性(P＜0.05),且PD+LY组细胞增殖的这种抑制作用明显高于PD组、LY组(P＜0.05).LY组细胞S期、G0/G1期比例的变化呈明显的时间和浓度依赖性(P＜0.05);PD组细胞各期比例的变化均无时间依赖性(P＞0.05),但G0/G1期、S期比例的变化呈明显的浓度依赖性(P＜0.05);PD+LY组与PD组、LY组比较,G0/G1期比例明显增加、S期比例明显减少(P＜0.05).PD+LY组细胞凋亡率为(63.3±0.5)%,明显高于PD组、LY组[分别为(30.7±20.1)%和(40.8±1.3)%,P＜0.01].(2)注射PD98059和(或)LY294002后,随着时间的延长,PD组、LY组、PD+LY组裸鼠移植瘤体积增长相对缓慢,对照组移植瘤体积增长明显,PD组、LY组、PD+LY组分别与对照组比较,差异均有统计学意义(P＜0.05);PD+LY组分别与PD组、LY组比较,差异也均有统计学意义(P＜0.05),而PD组与LY组比较,差异无统计学意义(P＞0.05).LY组、PD组、PD+LY组抑瘤率分别为(32±16)%、(38±17)%、(68±9)%,PD+LY组明显高于LY组、PD组(P＜0.05).LY组、PD组、PD+LY组细胞凋亡指数分别为(13.7±1.5)%、(14.1±1.2)%、(29.0±1.8)%,PD+LY组明显高于LY组、PD组(P＜0.01).LY组、PD组、LY+PD组裸鼠移植瘤组织中p-ERK和p-Akt蛋白的表达强度均明显弱于对照组.结论 信号传导通路抑制剂PD98059、LY294002能够抑制体外及体内子宫内膜癌细胞的生长,并促进其凋亡.

Abstract：

Objective To investigate the effects of signal pathway inhibitors PD98059 and LY294002 on cell proliferation, apoptosis, expressions of phosphorylated extracellular signal-regulared kinase (p-ERK) and phosphorylated protein kinase B ( p-Akt) in endometrial carcinoma xenografts. Methods Human endometrial carcinoma Ishikawa cells were cultured in vitro. The effects of PD98059 and LY294002 on proliferation, apoptosis, and cell cycle distribution of endometrial cancer cells were detected by monotetrazolium ( MTT) assay and fluorescence-activated cell sorting technique. The models of xenografted tumor were established by the subcutaneous inoculation in 24 nude mice, and then they were randomly divided into 4 groups ( n = 6) , normal saline group, PD98059 group (PD group) , LY294002 group ( LY group) or PD98059 + LY294002 group ( PD + LY group) by intraperitoneal injections, respectively. The anti-tumor efficacy was evaluated by measuring tumor volume and tumor growth status. The histopathological change of tumor specimens was observed using HE staining and terminal deoxynucleotidyl transferasemediated dUTP-digoxigen in nick and labeling method (TUNEL) testing and the expression levels of p-ERK and p-Akt were detected by immunohistochemistry method. Results ( 1) The proliferation of Ishikawa cells were suppressed after treated by PD98059 and ( or) Y294002, in which A570 values of cells decreased showing both time-dependent and concentration-dependent manner ( LY294002: Fgroup = 9. 801, P = 0. 002; Ftime = 10. 398, P = 0. 001. PD98059: Fgroup= 8. 213, P = 0. 015; Ftime = 6. 839, P = 0. 036). Cell cycle distribution analysis revealed that percentage of Ishikawa cells at G0/G1 phase(Ftime =35.049, P= 0.004; Fgroup = 32. 024, P ＜0. 01) increased and percentage of S phase cells (Ftime = 7. 789, P = 0. 049; Fgroup = 30. 132, P ＜0. 01) decreased significantly. The percentage of apoptotic cells increased significantly among PD group, LY group and PD + LY group, in which there were significant difference [(63. 3 ±0.5)% vs (30. 7 ± 20. 1) % vs(40. 8 ± 1. 3) % ; F = 621. 059, P ＜ 0. 01]. (2) Compared with the control group, the increasing of transplanting tumor volume in the treated groups were obviously ( F = 23. 545 , P ＜ 0. 01) , and the inhibited rate of the tumor was higher in PD + LY group than that in PD group or LY group [(68 ± 9 ) % vs ( 32 ± 16 ) % or ( 38 ± 17 ) % ; F = 10. 283 , P ＜ 0. 05]. ( 3 ) HE staining shown that there were different degrees of necrosis for endometrial carcinoma cell in different groups. The apoptosis of tumor cells were significantly increased in treated groups by TUNEL testing [(13. 7 ± 1. 5)% , ( 14. 1 ± 1. 2)% , (29. 0 ± 1. 8 ) % ; F = 320. 344, P ＜ 0. 01]. Immunohistochemistry results demonstrated that the expressions of p-ERK and p-Akt in treated groups were lower than that in control group, of which LY + PD group was the lowest one. Conclusion The signal pathway inhibitors PD98059 and LY294002 could inhibit the growth of human endometrial carcinoma in vivo and in vitro, in which may induce cell apoptosis.     

Quantitative analysis of telomerase hTERT mRNA and telomerase activity in endometrioid adenocarcinoma and in normal endometrium.

OBJECTIVES: In the current study, the quantitative levels of telomerase hTERT mRNA and the functional telomerase repeat amplification protocol (TRAP) assay were correlated with tumor grade in endometrial carcinomas and with the histologic phase of normal endometrium. METHODS: Twenty-six samples of endometroid adenocarcinoma and 20 cases of benign endometrium were obtained from hysterectomy specimens. Total RNA was extracted from each tissue sample and used for quantitative real-time RT-PCR of hTERT mRNA and the levels were standardized to the levels of ribosomal RNA. Quantitative determination of telomerase activity was performed by the polymerase chain-based TRAP assay and the levels of expression were defined by the ratio of radioactivity incorporated into the 6-bp telomerase amplification products versus the radioactivity incorporated into an internal standard (telomerase/ITAS x 100 = 1 RU). Statistical analyses were performed using the Fisher exact test or chi2 test, a Wilcoxon rank sum test, and a linear regression analysis. RESULTS: hTERT mRNA and telomerase activity levels showed a linear association in the study group (P = 0.006, R2 = 0.139). hTERT mRNA levels and telomerase activity levels were significantly higher in endometrial cancer (179 pg/ng rRNA, 44 relative units (RU)) than in normal endometrium (45 pg/ng), (15 RU) (P = 0.009, P = 0.006). In normal endometrium, hTERT mRNA and telomerase activity levels were highest in the proliferative phase (74 pg/ng rRNA, 25 RU) and were relatively low in secretory (13 pg/ng rRNA, 6 RU) and atrophic endometrium (9 pg/ng rRNA, 2 RU). CONCLUSION: These results suggest that the quantitative analysis of hTERT and telomerase activity may have potential roles as diagnostic or prognostic adjuncts for both premenopausal and postmenopausal patients with endometrial cancer.     

硫氢化钠通过PI3K/AKT信号通路促进子宫内膜基质细胞增殖

目的:探究硫氢化钠对子宫内膜基质细胞系增殖的作用。方法:测定硫化氢合成酶胱硫醚-β-合成酶(CBS)和胱硫醚-γ-裂解酶(CSE)在子宫内膜异位症(内异症)异位灶组织和正常内膜组织中的表达,用硫化氢供体(硫氢化钠)及PI3K/AKT通路特异性抑制剂LY294002处理正常人子宫内膜基质细胞系(ESCL)后,检测硫氢化钠和LY294002对ESCL增殖的影响。结果:硫化氢合成酶CBS和CSE在子宫内膜异位症异位灶中的表达高于正常子宫内膜,内膜腺上皮细胞较内膜间质细胞表达高;在一定浓度范围内硫氢化钠促进ESCL增殖;应用LY294002后部分拮抗硫氢化钠的增殖作用,差异有统计学意义(P0.01)。结论:硫氢化钠可在体外促进子宫内膜间质细胞的增殖,这一效应可能部分通过PI3K/Akt信号通路得以实现。异位灶CBS和CSE的高表达可能通过产生高水平的硫化氢,进而促进子宫内膜间质细胞增殖来促进内异症进展。     

信号通路抑制剂对PTEN基因不同表达状态子宫内膜癌细胞的作用

目的 比较相关信号通路抑制剂诱导PTEN基因不同表达状态子宫内膜癌细胞的增殖和凋亡情况.方法 以PTEN反义寡核昔酸及PTEN真核表达载体转染子宫内膜癌细胞(HEC-1A、Ishikawa)后,激光共聚焦显微镜观察PTEN蛋白的表达.表皮生长因子受体、丝裂原活化蛋白激酶及雷帕霉素靶蛋白信号通路抑制剂--RG-14620、SB203580(SB)及西罗莫司分别处理HEC-1A、HEC-1A-PTEN-null、Ishikawa、Ishikawa-PTEN细胞,荧光染色法、流式细胞仪、四甲基偶氮唑蓝比色法分别检测细胞凋亡时的形态学改变、细胞凋亡率、细胞周期分布、细胞存活率.结果 转染后,Ishikawa-PTEN细胞内PTEN蛋白表达增加,HEC-1A-FFEN-null细胞内PTEN蛋白表达受到抑制.RG-14620、SB及西罗莫司处理后,Ishikawa和HEC-1A-PTEN-null细胞荧光染色见核呈浓集周缩改变;细胞发生明显凋亡及G1期阻滞,尤以SB作用最为显著,Ishikawa+SB、HEC-1A-PTEN-null+SB的细胞凋亡率分别为(37.8±0.8)%、(31.6±0.8)%,G_1期细胞比例增加[分别为(87.5±1.9)%、(84.1±3.2)%];细胞增殖受到抑制,尤以SB处理后作用为显著,Ishikawa+SB、HEC-1A-PTEN-null+SB的细胞存活率仅为(49.0±1.7)%、(54.0±2.1)%.结论 PTEN基因缺失使相应信号通路抑制剂作用的子宫内膜癌细胞增殖明显受抑,细胞阻滞于G1期,细胞凋亡增加,对相关信号通路抑制剂的敏感性增加.     

宫颈癌细胞系中hTERT启动子水平及其与端粒酶活性相关性的研究

目的:探讨宫颈癌细胞系中人端粒酶逆转录酶(hTERT)启动子的活性及其与hTERT mRNA表达和端粒酶活性之间的关系。方法:应用脂质体转染法将hTERT核心启动子基因转入宫颈癌细胞系Hela和正常人皮肤表皮细胞中,并用荧光素酶检测实验检测其中hTERT启动子的活性;应用RT-PCR半定量法检测2种细胞中的hTERT mRNA表达水平:应用PCR-ELISA定量检测这2种细胞中的端粒酶活性。同时以端粒酶阳性的永生化人胚肾成纤维细胞系HEK293的检测结果作为阳性对照,以端粒酶阴性的人胚肺成纤维细胞系HELF的检测结果作为阴性对照。结果:宫颈癌细胞系HeLa和正常人皮肤表皮细胞中的hTERT启动子活性(视每种细胞中pGL3一control的启动子活性为100％)分别为20.1％和0.3％;hTERT mRNA相对表达水平分别为0.63和0(视HEK293表达水平为1):端粒酶活性分别为0.393和0.144(视>0.2为阳性)。结论:宫颈癌细胞系中hTERT启动子活性、hTERT mRNA表达水平和端粒酶活性均特异性增高,而正常皮肤表皮细胞中则受抑制或不表达。hTERT启动子活性水平与hTERT mRNA表达水平及端粒酶活性之间有显著相关性。