星形孢菌素对前列腺癌细胞株PC-3增殖和凋亡的影响

目的:探讨蛋白激酶C抑制剂星形孢菌素(ST)对前列腺癌细胞株PC-3增殖及凋亡的影响。方法:以ST(10-8mol/L)处理体外培养的PC-3细胞株。采用Western印迹检测细胞周期蛋白cyclin A、cyclin D1表达的变化。通过MTT实验、平板克隆实验检测ST对PC-3细胞增殖能力的影响。流式细胞仪检测各组细胞凋亡的情况。光镜观察细胞形态学的改变。结果:PC-3细胞经ST处理后cyclin A、cyclin D1蛋白表达明显降低。MTT实验结果显示ST对PC-3细胞的抑制作用自48 h后(19.35%)有显著性(F=31.06,P<0.01)。平板克隆实验结果显示组细胞克隆形成率ST组[(37.10±3.43)%]明显低于对照组((64.80±4.34)%,χ2=14.59,P<0.05]及DMSO组[(62.80±4.36)%,χ2=12.50,P<0.05]。流式细胞术结果显示ST组凋亡率(19.6±2.20)%与对照组(5.33±1.40)%和DMSO组(5.50±0.96)%比较显著增加(F=104.36,P<0.01)。光镜下可见:与对照组及DMSO组比较ST组细胞生长状态明显变差,细胞变圆,边缘模糊。结论:ST可以抑制前列腺癌细胞的生长和增殖,诱导细胞凋亡。     

Emodin induces apoptosis in human prostate cancer cell LNCaP

AIM: To elucidate effects and mechanisms of emodin in prostate cancer cells. METHODS: Viability of emodin-treated LNCaP cells and PC-3 cells was measured by MTT assay. Following emodin treatments, DNA fragmentation was assayed by agarose gel electrophoresis. Apoptosis rate and the expression of Fas and FasL were assayed by flow cytometric analysis. The mRNA expression levels of androgen receptor (AR), prostate-specific antigen (PSA), p53, p21, Bcl-2, Bax, caspase-3, -8, -9 and Fas were detected by RT-PCR, and the protein expression levels of AR, p53 and p21 were detected by Western blot analysis. RESULTS: In contrast to PC-3, emodin caused a marked increase in apoptosis and a decrease in cell proliferation in LNCaP cells. The expression of AR and PSA was decreased and the expression of p53 and p21 was increased as the emodin concentrations were increased. In the same time, emodin induced apoptosis of LNCaP cells through the upregulation of caspase-3 and -9, as well as the increase of Bax /Bcl-2 ratio. However, it did not involve modulation of Fas or caspase-8 protein expression. CONCLUSION: In prostate cancer cell line, LNCaP, emodin inhibites the proliferation by AR and p53-p21 pathways, and induces apoptosis via the mitochondrial pathway.     

环巴胺对人前列腺癌LNCaP细胞增殖和凋亡作用及对PCA3基因表达的影响

目的:探讨环巴胺对人前列腺癌LNCaP细胞增殖和凋亡的作用及对PCA3基因表达的影响。方法:不同浓度环巴胺(1、5、10、15μmol/L)干预LNCaP细胞,以只加入RPMI 1640培养液为空白对照组,分别在不同作用时间(24、48、72h),用MTT法检测其对细胞增殖的抑制、流式细胞术观察细胞凋亡率变化、Hoechst染色观察凋亡细胞形态变化、实时荧光定量逆转录聚合酶链反应(FQ-RT-PCR)观察对PCA3基因表达的影响。结果:5、10、15μmol/L环巴胺对LNCaP细胞增殖均有显著抑制作用,与空白对照组相比差异有显著性(P0.01),10μmol/L组于48h达到半数抑制量(IC50);10、15μmol/L组24、48、72hLNCaP细胞的凋亡率分别为37.21%、57.38%、57.98%和21.16%、71.31%、72.90%,与空白对照组相比差异均有显著性(P0.01)。随着环巴胺浓度增大和作用时间的延长,LNCaP细胞凋亡显著增加。PCA3基因的表达随着环巴胺浓度的上升呈现明显的递减趋势,较空白对照组显著降低(P0.01)。浓度为10μmol/L时,不同作用时间PCA3基因的表达均极低。结论:环巴胺浓度为10、15μmol/L作用48、72h时能够明显抑制LNCaP细胞的增殖,诱导细胞凋亡,并显著下调LNCaP细胞PCA3基因的表达。     

选择性COX-2抑制剂NS398对前列腺癌PC-3细胞增殖与凋亡的影响

目的观察环氧化酶-2(COX-2)抑制剂NS398对前列腺癌细胞PC-3增殖和凋亡的影响。方法采用四甲基偶氮唑蓝法(MTT法)检测不同浓度和不同时间NS398对PC-3细胞增殖的影响;RT-PCR法检测不同浓度NS398作用PC-3细胞24h后COX-2 mRNA的表达;酶联免疫测定法(ELISA)检测不同浓度NS398作用PC-3细胞24h后PGE2释放水平;流式细胞仪检测不同浓度NS398作用PC-3细胞24h后细胞凋亡情况。结果NS398可以抑制PC-3细胞的增殖,呈时间和剂量依赖性;RT-PCR和ELISA法检测结果显示,随着NS398浓度增高,PC-3细胞COX-2 mRNA表达和PGE2释放水平呈下调趋势;细胞凋亡检测结果显示100、200μmol/LNS398对PC-3细胞具有诱导凋亡的作用。结论NS398可能通过COX-2依赖性途径抑制前列腺癌PC-3细胞增殖,促进肿瘤细胞凋亡。     

miR-124通过靶向调控PKM2基因的表达抑制前列腺癌PC3细胞的增殖

目的:探讨miR-124抑制前列腺癌PC3细胞增殖活性的机制。方法:利用荧光素酶报告基因验证miR-124能否靶向作用于丙酮酸激酶M2型(PKM2)3'端非编码区(UTR)。将miR-124 mimic转染至PC3细胞后,采用实时荧光定量PCR和Western印迹检测前列腺癌PC3细胞PKM2 mRNA和蛋白的表达水平,MTT法检测miR-124 mimic与PKM2 siRNA对PC3细胞生长活性的影响。结果:与人前列腺上皮细胞RWPE-1比较,PC3细胞中PKM2 mRNA和蛋白水平表达分别上调(5.12±0.35)倍和(4.05±0.20)倍(P0.05)。荧光素酶报告基因结果证实,PKM2是miR-124调控的靶基因,miR-124可特异性地结合于PKM2 mRNA的3'-UTR。转染miR-124 mimic 24 h后,PKM2蛋白水平下调至阴性对照组(0.16±0.04)倍(P0.05),但对PKM2 mRNA表达无显著影响(P0.05)。MTT结果显示,转染miR-124 mimic和PKM2 siRNA都能显著抑制PC3细胞的增殖,但miR-124 mimic对PC3细胞生长活性的抑制能力较PKM2 siRNA强。转染miR-124 mimic和PKM2 siRNA 24 h和48 h后,PC3细胞的增殖率分别为(66.20±5.10)%和(82.10±6.35)%(P0.05)、(49.34±2.37)%和(70.10±5.80)%(P0.05)。结论:miR-124可通过靶向调控PKM2基因的表达而抑制前列腺癌PC3细胞的增殖。     

Tetrandrine suppresses proliferation,induces apoptosis,and inhibits migration and invasion in human prostate cancer cells

Tetrandrine (TET), a traditional Chinese medicine, exerts remarkable anticancer activity on various cancer cells. However, little is known about the effect of TET on human prostate cancer cells, and the mechanism of function of TET on prostate cancer has not yet been elucidated. To investigate the effects of TET on the suppression of proliferation, induction of apoptosis, and inhibition of migration and invasion in human prostate cancer cell lines, DU145 and PC-3. Inhibition of growth was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and clone formation assay, and flow cytometry analysis was performed to detect the induction of apoptosis. Activation of poly (ADP-ribose) polymerase, caspase-3, Akt, phospho-Akt, Bcl-2, and Bax was analyzed by Western blotting. Wound healing assay and transwell migration assay were used to evaluate the effect of TET on migration and invasion of cancer cells. TET inhibited the growth of DU145 and PC–3 cells in a dose- and time-dependent manner. Cell cloning was inhibited in the presence of TET in DU145 and PC-3 cells. TET suppressed the migration of DU145 and PC-3 cells. Transwell invasion assay showed that TET significantly weakened invasion capacity of DU145 and PC-3 cells. TET exhibited strong inhibitory effect on proliferation, migration, and invasion of prostate cancer cells. In addition, TET induced apoptosis in a dose-dependent manner by activating the caspase cascade and inhibiting phosphoinositide 3-kinase-Akt signal pathway. The accumulating evidence suggests that TET could be a potential therapeutic candidate against prostate cancer in a clinical setting.     

Therapeutic potential of curcumin in human prostate cancer. III. Curcumin inhibits proliferation, induces apoptosis, and inhibits angiogenesis of LNCaP prostate cancer cells in vivo

BACKGROUND: Earlier work from our laboratory highlighted the therapeutic potential of curcumin (turmeric), used as a dietary ingredient and as a natural anti-inflammatory agent in India and other Southeast Asian countries. This agent was shown to decrease the proliferative potential and induce the apoptosis potential of both androgen-dependent and androgen-independent prostate cancer cells in vitro, largely by modulating the apoptosis suppressor proteins and by interfering with the growth factor receptor signaling pathways as exemplified by the EGF-receptor. To extend these observations made in vitro and to study the efficacy of this potential anti-cancer agent in vivo, the growth of LNCaP cells as heterotopically implanted tumors in nude mice was followed. METHODS: The androgen-dependent LNCaP prostate cancer cells were grown, mixed with Matrigel and injected subcutaneously into nude mice. Experimental group received a synthetic diet containing 2% curcumin for up to 6 weeks. At the end point, sections taken from the excised tumors were evaluated for pathology, cell proliferation, apoptosis, and vascularity. RESULTS: Curcumin causes a marked decrease in the extent of cell proliferation as measured by the BrdU incorporation assay and a significant increase in the extent of apoptosis as measured by an in situ cell death assay. Moreover, a significant decrease in the microvessel density as measured by the CD31 antigen staining was also seen. CONCLUSIONS: Curcumin could be a potentially therapeutic anti-cancer agent, as it significantly inhibits prostate cancer growth, as exemplified by LNCaP in vivo, and has the potential to prevent the progression of this cancer to its hormone refractory state.     

参附注射液对前列腺癌PC-3细胞凋亡诱导的影响

目的:研究参附注射液(SF)对人前列腺癌PC-3细胞凋亡的影响及可能机制。方法:实验设立对照组和SF 50、100、200μl/ml组,Annexin V/PI染色流式细胞术检测细胞凋亡,RT-PCR检测p53 mRNA表达。结果:与对照组比较,作用24、48、72 h后,SF 50、100、200μl/ml组PC-3细胞存活率显著减少(P均0.05)。SF各组24 h存活率分别为(93.76±2.63)%、(81.21±1.80)%、(18.01±3.84)%;48 h存活率分别为(94.67±1.11)%、(78.33±2.89)%、(10.34±1.44)%;72 h存活率分别为(91.30±0.47)%、(36.67±1.56)%、(1.33±0.32)%,呈浓度和时间依赖性。作用48 h后,p53 mRNA表达明显升高(P0.05)。结论:SF可以诱导PC-3细胞凋亡,其作用机制可能与p53表达增高相关。     

培养液中胆固醇缺乏对前列腺癌PC-3细胞生长和凋亡的影响

目的:探讨培养液中胆固醇水平对人前列腺癌PC-3细胞生长抑制及凋亡调控的作用。方法:前列腺癌PC-3细胞分别培养于普通和胆固醇缺乏培养液中,再分别加入不同剂量血小板源性生长因子PDGF或EGF作用后,倒置显微镜观察细胞形态,MTT法检测细胞的增殖抑制情况,流式细胞仪进行细胞凋亡率及细胞周期时相分析。结果:与普通培养液组比较,胆固醇缺乏培养液组细胞明显变圆、体积缩小、脱壁细胞增多。MTT法检测显示,胆固醇缺乏培养液组细胞增殖显著抑制,并呈剂量依赖性。流式细胞分析显示胆固醇缺乏培养液组细胞凋亡率同普通培养液组相比无显著差异。当加入PDGF或EGF刺激细胞增殖时,普通培养液组细胞数目显著增加,而在胆固醇缺乏培养液组脱壁细胞增加,细胞凋亡增多,同普通培养液组相比存在显著差异。流式细胞术分析细胞周期显示,同普通培养液组相比,胆固醇缺乏培养液组停滞在G0/G1期细胞增加,而S、G2/M期细胞减少。结论:胆固醇缺乏对PC-3细胞增殖有显著抑制作用,其作用机制并不是简单增加细胞凋亡,而可能是在不利增殖条件下,PC-3细胞的一种自我调节机制。     

沉默PKM2增强藤黄酸诱导人前列腺癌PC3细胞凋亡的敏感性

目的:研究沉默丙酮酸激酶M2型(PKM2)对藤黄酸(GA)诱导人前列腺癌PC3细胞凋亡的影响,并探讨其潜在的作用机制。方法:设计并合成针对PKM2的3条特异性siRNA及阴性对照siRNA(si-NC)。利用脂质体将PKM2 siRNA和si-NC转染至人前列腺癌PC3细胞并检测PKM2 siRNA的沉默效率。MTT和吖啶橙/溴化乙啶(AO/EB)双重染色法分别检测沉默PKM2后GA对PC3细胞生长活性和凋亡的影响。采用实时荧光定量PCR和Western印迹法分别检测c-myc和cyclin D1的mRNA和蛋白表达水平。结果:与si-NC组比较,3条PKM2 siRNA都能够有效下调PKM2的mRNA和蛋白表达水平,其中PKM2 siRNA-1的沉默效率最高。转染PKM2siRNA-1 24 h后,PC3细胞中PKM2 mRNA和蛋白表达水平分别下调70%和85%(P<0.05)。转染PKM2 siRNA-1后给予0.5μmol/L的GA处理24 h,PC3细胞生长活性明显受到抑制(对照组的68%)且凋亡诱导增加,而且c-myc和cyclin D1基因的mRNA和蛋白的表达水平显著下调(c-myc分别为对照组的50%和35%;cyclin D1分别为对照组的60%和20%,P<0.05)。结论:抑制PKM2能够提高GA诱导人前列腺癌PC3细胞凋亡的敏感性,PKM2可能成为GA治疗前列腺癌的有效增敏靶点。     

双环铂对激素抵抗型前列腺癌细胞PC3的凋亡诱导作用

目的采用体外实验观察双环铂对激素抵抗型前列腺癌细胞PC3的凋亡诱导作用,并初步探讨其凋亡机制。方法 CCK-8法观察双环铂对PC3细胞增殖的抑制,Hoechst染色荧光显微镜下观察凋亡细胞,Annexin-V-FITC/PI染色流式细胞仪检测细胞凋亡率,PI单染流式细胞仪检测细胞周期变化。结果双环铂可抑制PC3细胞的增殖,48hIC50为（195±19.0）×10-6 mol/L.;PC3细胞在经双环铂处理后,漂浮细胞呈明显的凋亡细胞形态,经Hoechst染色荧光显微镜下可见凋亡小体等典型的细胞核染色质形态学改变;双环铂诱导的PC3细胞凋亡呈剂量依赖性及时间依赖性。低浓度的双环铂可引起PC3细胞G2期阻滞,随药物浓度的升高sub-G1期细胞比例明显增加。结论体外实验显示双环铂可诱导PC3细胞的凋亡,双环铂对细胞周期的影响可视为其抗肿瘤活性的机制之一。     

下调PAR基因表达对前列腺癌PC3细胞凋亡及凋亡相关蛋白Bcl-2/Bax的影响

目的:本研究以RNA干扰技术下调PAR(prostate androgen regulated)基因表达,探讨其对前列腺癌PC3细胞增殖、凋亡及其相关蛋白Bcl-2/Bax表达水平的影响。方法:PC3细胞转染靶向PAR基因的siRNA,MTT法检测细胞增殖,用流式细胞术检测细胞凋亡,Western印迹检测Bcl-2和Bax蛋白表达水平。结果:PC3细胞PAR基因表达水平下调,此时处于G2-M期的细胞增加,为(29.95±3.25)%;细胞凋亡率亦明显增加,为(20.61±2.73)%,与对照组比较差异有显著性意义(P<0.01),同时Bcl-2蛋白表达下降,Bax表达水平升高,Bax/Bcl-2比值升高。结论:PAR基因表达下调可诱导细胞G2-M期阻滞和凋亡,其机制为抑制凋亡相关蛋白Bcl-2表达,同时促进Bax表达。     

The impact of altered annexin I protein levels on apoptosis and signal transduction pathways in prostate cancer cells

BACKGROUND: Although reduced expression levels of annexin I (ANX I) protein is a common finding in all stages of prostate cancer a causative relationship between ANX I dysregulation and prostate cancer development has yet to be established. METHODS: Annexin I expression was restored in LNCaP and MDA PCa 2b that normally express low or undetectable levels of ANX I protein. The impact of restoring ANX I expression on cell viability, colony formation in soft agar, apoptosis, and extracellular signal-regulated kinases (ERK), p38, c-Jun N-terminal kinases (JNK) activation was examined. RESULTS: Restoring ANX I expression reduced cell viability, colony formation, in addition to inducing apoptosis. The proliferative response of epidermal growth factor was blocked by restoring ANX I expression. Furthermore, increasing basal and induced levels of phosphorylated p38 and JNK were observed in prostate cancer cells following restoration of ANX I expression. CONCLUSIONS: Annexin I may have tumor suppressor functions in prostate cancer. The pro-apoptotic effect of ANX I involves the activation of p38 and JNK, which appears to shift the balance of signal transduction away from proliferation and toward apoptosis.     

Cell proliferation and apoptosis in prostate tumors and adjacent non-malignant prostate tissue in patients at different time-points after castration treatment

BACKGROUND: Androgen ablation is the standard treatment for advanced prostate cancer but the short-term cellular effects are largely unknown. METHODS: Sextant prostate biopsies were taken from 77 prostate cancer patients before and 1-10 days after castration treatment. Apoptosis, cell proliferation, and morphology were studied in malignant and non-malignant tissue, using stereological and immunohistochemical methods. RESULTS: Epithelial cell proliferation was significantly decreased both in non-malignant and malignant epithelium already 1 day after therapy. It remained low until day 7, but increased thereafter in the remaining non-malignant epithelial cells and in some tumors. Epithelial cell apoptosis was significantly increased during the first week and then returned to basal levels. The maximal apoptotic indexes, seven- and two-times the intact levels in the non-malignant and malignant glands, respectively, were found at days 3-4 or even earlier in the tumors. Signs of tumor shrinkage such as glandular collapse and decreased tumor cell size were observed from day 3 in most tumors. DISCUSSION: The present study shows that the magnitude and kinetics of the response to castration in the normal human prostate is very similar to the response previously described in rodents. We also demonstrate that most human prostate tumors rapidly respond to castration indicating the need for further evaluation of when and how to best monitor the effects of hormone ablation therapy in prostate cancer patients.     

Induction of mitotic arrest and apoptosis in human prostate cancer pc-3 cells by evodiamine

PURPOSE: Although evodiamine, an alkaloid isolated from Evodiae fructus, has been reported to exert anticancer activities, to our knowledge its target and mechanism of action have not yet been explored. We examined the anticancer activities and action mechanism of evodiamine. MATERIALS AND METHODS: Human prostate cancer PC-3 cells were used in this study. The cytotoxic effect and cell growth inhibition were examined using the MTT (3-(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide) assay and sulforhodamine B assay, respectively. The apoptotic effect was determined using TUNEL assay and the progression of cells through the cell cycle and cell apoptosis were examined by FACScan flow cytometry (Becton Dickinson, Sunnyvale, California). In situ mitotic spindle detection and in vitro tubulin polymerization assay were performed by immunofluorescence staining for beta-tubulin and CytoDYNAMIX ScreenTM3 (CDS-03) kits (Cytoskeleton, Denver, Colorado). RESULTS: It was found that treatment of PC-3 cells with evodiamine decreased the cell number in a concentration and time dependent manner, and effectively inhibited PC-3 cell growth via the induction of cell cycle arrest at the G2/M phase and subsequent apoptosis. In an in situ assay we found that evodiamine inhibited microtubule spindle formation. In a cell-free assay system of tubulin polymerization evodiamine inhibited the polymerization of microtubules in a concentration dependent manner. CONCLUSIONS: These data suggest that evodiamine shows anticancer activity through inhibition of tubulin polymerization. This antitubulin activity might make evodiamine a potential anticancer drug.     

The multikinase inhibitor sorafenib induces caspase-dependent apoptosis in PC-3 prostate cancer cells

The present study investigated the effects of the multikinase inhibitor sorafenib on androgen-independent can- cer cells viability and intracellular signaling. Human androgen-independent PC-3 prostate cancer cells were treated with sorafenib. At concentration that suppresses extracellular signal-regulated kinase phosphorylation, sorafenib treatment reduced the mitochondrial transmembrane potential. Sorafenib also down-modulated the levels of mye- loid cell leukemia 1, survivin and cellular inhibitor of apoptosis protein 2. Sorafenib induced caspase-3 cleavage and the mitochondrial release of cytochrome c. However, no nuclear translocation of apoptosis inducing factor was detected after treatment and the pan-caspase inhibitor Z-VAD-FMK had an obvious protective effect against the drug. In conclusion, sorafenib induces apoptosis through a caspase-dependent mechanism with down-regulated antiapoptotic proteins in androgen-independent prostate cancer cells in vitro.     

Transgelin induces apoptosis of human prostate LNCaP cells through its interaction with p53

The androgen receptor （AR） and its coregulators have important roles in the carcinogenesis of prostate cancer.p53 is an important tumour suppressor gerte,and the absence of a fundamental p53 response may predispose to cancer. Transgelin,known as an ARA54-associated AR inhibitor,can suppress AR function in LNCaP cells. In addition to these effects,we aimed to elucidate the proapoptotic effects of the protein on LNCaP and its underlying mechanisms,especially the interaction between transgelin and p53. Cell counting,flow cytometric analysis and terminal deoxynucleotidyl transferase-dUTP nick-end labelling assays were applied to measure the proapoptotic effect of transgelin. Using western blotting of p53 and double immunofluorescence staining of p53 with transgelin,we show that transfection of transgelin results in increasing cytoplasmic translocation of p53 and upregulation of p53 expression. We also found an interaction between transgelin and p53 in vivo by mammalian two-hybrid and coimmunoprecipitation assays. The activation of the mitochondria-associated apoptosis pathway was observed in LNCaP cells after transfection with transgelin. These results are indicative of p53-mediated mitochondria-associated apoptotic effects of transgelin on LNCaP cells in addition to its known suppressive effects on the AR pathway.