Potentiation of ceramide-induced apoptosis by p27kip1 Overexpression

The cyclin-dependent kinase inhibitor p27kip1 (p27) has been implicated in the regulation of cell cycle and apoptosis. Recently, we have demonstrated that ceramide induces apoptotic cell death associated with increase in the level of p27 in HL-60 cells. In the present study, we showed that overexpression of p27 increases ceramide-induced apoptotic cell death in HL-60 cells. Furthermore, overexpression of p27 accelerated DNA fragmentation, PARP cleavage and cytochrome c release induced by ceramide. In addition, ceramide induced Bax expression independent of p27. These findings indicate that enhanced effect on apoptosis by p27 is associated with mitochondrial signaling which involves cytochrome c release.     

Genistein inhibits rat aortic smooth muscle cell proliferation through the induction of p27kip1

Diet is one of the most important factors that influence the risks for cardiovascular diseases. Genistein, an isoflavone found in soy, may benefit the cardiovascular system. Here, we investigated the effect of genistein on platelet-derived growth factor (PDGF)-BB-induced proliferation of primary cultured rat aortic smooth muscle cells (RASMCs). Genistein significantly inhibited 25 ng/ml PDGF-BB-induced RASMC proliferation and [3H]-thymidine incorporation into DNA at 10, 20, and 40 microM. In accordance with these findings, genistein blocked the PDGF-BB-inducible progression through G0/G1 to S phase of the cell cycle in synchronized cells. Western blot analysis showed that genistein not only inhibited phosphorylation of retinoblastoma protein (pRb) and expression of cyclin E, cyclin-dependent kinase (CDK) 2, and proliferating cell nuclear antigen (PCNA) protein, but also inhibited downregulation of cyclin-dependent kinase inhibitor (CKI) p27kip1. However, genistein did not affect p21cip1, CDK4, and cyclin D1 expression or early signal transduction through PDGF beta-receptor, extracellular signal-regulated kinases 1/2 (ERK1/2), Akt, and phospholipase C (PLC) gamma1 phosphorylation. These results suggest that genistein inhibits PDGF-BB-induced RASMC proliferation via G0/G1 arrest in association with induction of p27kip1, which may contribute to the beneficial effects of genistein on the cardiovascular system.     

TFAR19蛋白协同米非司酮对前列腺癌PC-3M细胞凋亡的影响

目的初步探讨TFAR19协同米非司酮(MIF)对前列腺癌PC-3M细胞凋亡的影响。方法构建TFAR19真核表达载体,用脂质体介导的方法转染PC-3M细胞。MTT法检测5、10、20、50和100μmol·L-1MIF作用于前列腺癌PC-3M细胞24~96h的吸光度(A)值。在转染TFAR19的细胞中加入20mol·L-1MIF培养24、48h,MTT比色法检测细胞增殖,原位末端标记(TUNEL)法检测细胞凋亡率,透射电镜进一步观察细胞超微结构的改变。结果构建了PCI-neo-TFAR19真核表达载体并在转染的PC-3M细胞中得到了瞬时表达。MTT实验表明,与对照组相比,5、10μmol·L-1MIF组的A值差异无统计学意义(P>0.05),20、50和100μmol·L-1MIF组的A值差异有统计学意义(P<0.01),MIF对前列腺癌PC-3M细胞的抑制作用呈时间、剂量依赖性;转染PCI-neo-TFAR19并加入20 mol·L-1MIF后,与对照组及单独应用MIF组相比,细胞生长明显受到抑制(P<0.01),细胞凋亡率明显增加(P<0.01),透射电镜观察到典型的细胞凋亡特征(细胞体积缩小,核皱缩、碎裂,染色质呈块状边集等)。结论TFAR19蛋白能够协同米非司酮促进前列腺癌PC-3M细胞凋亡,有望成为前列腺癌的辅助治疗药物。     

p27(kip1) and Ki-67 (MIB1) immunohistochemical expression in radical prostatectomy specimens of patients with clinically localized prostate cancer

The immunohistochemical expressions (IE) of p27(kip1) and Ki-67 (MIB-1), both involved in cell cycle regulation and cell proliferation, and their ability to predict biochemical failure, were assessed in patients with clinically localized prostate cancer who had underdone radical prostatectomy of curative intent. In addition, p27(kip1) and Ki-67 (MIB1) expressions were correlated with several pre-operative and post-operative parameters, such as Gleason score, extracapsular extension, seminal vesicle involvement, pelvic lymph nodes metastasis, positive surgical margins, coexistence of high-grade prostatic intraepithelial neoplasia, tumour size, prostate volume and PSA levels. Our analysis involved 130 consecutive radical prostatectomy specimens. A statistically significant correlation of low p27(kiP1) IE with seminal vesicles involvement, increased tumour volume and high pre-operative PSA values was documented. Low p27(kiP1) IE was significantly correlated with an increased likelihood of biochemical failure after radical prostatectomy. In addition, the increased IE of Ki-67 (MIB1) correlated significantly with metastatic disease in the pelvic lymph nodes and was a significant predictor of biochemical failure. Cox regression analysis, which included p27(kip1) expression, Ki-67 (MIB1) expression and all the pre-operative and post-operative parameters, showed that pelvic lymph node involvement and Ki-67 (MIB1) IE were independent prognostic markers of biochemical failure after radical prostatectomy.     

Induction of CDK inhibitors (p21(WAF1) and p27(Kip1)) and Bak in the beta-lapachone-induced apoptosis of human prostate cancer cells

beta-Lapachone, a novel anti-neoplastic drug, induces various cancer cells to undergo apoptosis. In a previous report, we showed that beta-lapachone-induced apoptosis of HL-60 cells is mediated by oxidative stress. However, in the present study, we found that beta-lapachone-induced apoptosis of human prostate cancer (HPC) cells may be independent of oxidative stress. In contrast to the 10-fold beta-lapachone-induced increase in H(2)O(2) production seen in HL-60 cells, only a 2- to 4-fold increase was observed in HPC cells. N-acetyl-L-cysteine (NAC), a thiol antioxidant, inhibited the apoptosis in DU145 cells after 12 h exposure to beta-lapachone. Nonetheless, NAC, along with other antioxidants, failed to exert similar effect in HPC cells subjected to beta-lapachone treatment for 24 h. Under this premise, we suggest that the oxidative stress may not play a crucial role in beta-lapachone-mediated HPC cell apoptosis. Here we demonstrate that damage to genomic DNA is the trigger for the apoptosis of HPC cells induced by beta-lapachone. According to our results, beta-lapachone stimulates DNA dependent kinase expression and poly(ADP-ribose) polymerase cleavage in advance of significant morphological changes. beta-Lapachone promotes the expression of cyclin-dependent kinase (cdk) inhibitors (p21(WAF1) and p27(Kip1)), induces bak expression, and subsequently stimulates the activation of caspase-7 but not of caspase-3 or caspase-8 during the apoptosis of HPC cells. Taken together, these results suggest that the signaling pathway involving the beta-lapachone-induced apoptosis of HPC cell may be by DNA damage, induction of cdk inhibitors (p21 and p27), and then subsequent stimulation of caspase-7 activation.     

Pamidronate inhibits antiapoptotic bcl-2 expression through inhibition of the mevalonate pathway in prostate cancer PC-3 cells

Bisphosphonates are expected to be efficacious to prevent the growth of metastatic cancer in bone tissue. Bone metastases often occur in patients with various cancers, such as breast, lung and prostate cancer. Bcl-2 is a potent antiapoptotic protein and its expression is known to be closely related to its function. In this study, to investigate the effect of bisphosphonates on cancer cells, we focused on bcl-2 expression in bisphosphonate-treated prostate cancer cells. First, we observed that bcl-2 mRNA expression in PC-3 was significantly inhibited to 12% of the control level by treatment with 100 μM pamidronate for 12 h. Inhibition was seen in cells treated with nitrogen-containing bisphosphonates, which have the ability to inhibit isoprenoid biosynthesis via the mevalonate pathway, but not in non-nitrogen-containing etidronate. Simultaneous treatment with geranylgeraniol, an intermediate of the mevalonate pathway, significantly blocked inhibition by pamidronate, and treatment with geranylgeranyl transferase inhibitor GGTI-286 also suppressed bcl-2 mRNA expression. Furthermore, pamidronate inhibited the translocation of Rap1 protein to the membrane fraction, suggesting that a change in posttranslational modification of Rap1 occurred in treated cells. Finally, knockdown of Rap1 by siRNA resulted in the inhibition of bcl-2 expression. These results strongly indicate that bcl-2 reduction in bisphosphonate-treated PC-3 cells is dependent on inhibition of the mevalonate pathway. The inhibitory effect of bisphosphonates on bcl-2 expression shown in prostate cancer cell line should be tested in animal experiments and clinical studies.     

p27(kip1) functional regulation in human cancer: a potential target for therapeutic designs

The mitotic cell cycle is a tightly regulated process that ensures the correct division of one cell into two daughter cells. Progress along the different phases of the cell cycle is positively regulated by the sequential activation of a family of serine-threonine kinases called CDKs (Cyclin Dependent Kinases). Their activity is counteracted by small proteins known as CDK inhibitors (CKI) that ensure the correct timing of CDK activation in the different phases of the cell cycle. The present review will deal with the role of one of this CKI, p27(kip1), in human cancer, focusing in particular on the mechanisms underlying its functional inactivation in tumor cells. p27(kip1) protein downregulation is usually achieved by proteasomal degradation and is often correlated to a worse prognosis in several types of human cancers, resulting in the reduction of disease free and overall survival. More recently, it has been proposed that p27(kip1) protein, rather than degraded, can be functionally inactivated. The mechanisms and the implications of these two types of p27(kip1) deregulation will be discussed and some potential therapeutic approaches targeting p27(kip1) functions will be proposed.     

JAK2/STAT3信号转导通路在岩大戟内酯B诱导的前列腺癌细胞PC-3凋亡中的作用

目的探讨岩大戟内酯B诱导的人前列腺癌细胞系PC-3细胞凋亡以及JAK2/STAT3信号转导通路在此过程中的作用。方法不同浓度的岩大戟内酯B处理人前列腺癌细胞系PC-3细胞0、24、48、72 h后,采用台盼蓝染色法检测PC-3细胞存活率;采用Annexin V-FITC/PI双染流式细胞仪检测PC-3细胞凋亡率;Western blot分析检测岩大戟内酯B作用不同时间后JAK2/STAT3信号转导通路的表达;预先用不同浓度的JSI-124(选择性STAT3途径抑制剂)处理PC-3细胞60 min,观察岩大戟内酯B作用不同时间后PC-3细胞的凋亡情况。结果岩大戟内酯B能够诱导前列腺癌细胞PC-3凋亡,降低磷酸化-JAK2/STAT3的表达,JSI-124可以提高岩大戟内酯B诱导的PC-3细胞凋亡率。结论 JAK2/STAT3信号转导通路参与了岩大戟内酯B诱导的PC-3细胞凋亡过程。JSI-124通过特异性地抑制STAT3活性提高了岩大戟内酯B诱导的PC-3细胞凋亡率。     

Production of Cyr61 protein is modulated by extracellular acidification and PI3K/Akt signaling in prostate carcinoma PC-3 cells

High expression of Cyr61, an extracellular cysteine-rich heparin-binding protein, has been associated with a malignant cell phenotype and poor outcome in prostate cancers. Although Cyr61 was found by us to be overproduced in androgen-independent PC-3 cells treated with N-acetylcysteine (NAC), its significance is still unclear. We therefore aimed to determine how and why Cyr61 protein is overexpressed in NAC-treated cells. Here, we found that Cyr61 protein level markedly increased in cells treated with NAC at high cell seeding density. Silencing of Cyr61 by siRNA induced enhanced activity of caspase-3/7, upregulation of the proapototic Bok, Bim_L and Bim_S, cleavage of apoptosis hallmarkers such as Bax, PARP and caspase-3, and downregulation of antiapoptotic Bcl2, Bcl-xL and Mcl-1 proteins. NAC treatment caused a reduction of extracellular medium pH to acidic and an increase in Akt phosphorylation, after which the replacement with NAC-free medium returned them to control levels within 24 h. Acid stimulation increased the levels of Cyr61 and p-Akt proteins, whereas it suppressed the induction of proapoptotic and antiapoptotic proteins. Overall, our data indicate that PC-3 cells overproduce Cyr61 protein via activation of the PI3K/Akt signaling as a part of the survival mechanisms under the conditions causing extracellular acidity and further cytotoxicity.     

Investigation of extrinsic and intrinsic apoptosis pathways of new clerodane diterpenoids in human prostate cancer PC-3 cells

In our continuing search to discover bioactive compounds from natural products, we isolated six new clerodane diterpenes, caseamembrins A to F, from Casearia membranacea and examined their antiproliferative activities in human hormone-resistant prostate cancer PC-3 cells. All of these compounds displayed effective antiproliferative activity using sulforhodamine B assays and induced cell apoptosis by a terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL)-reaction technique. The data demonstrated that caseamembrin C was the most effective compound among these clerodane diterpenoids. Caseamembrin C induced down-regulation of Bcl-2 and Bcl-xL expression, while up-regulation of proapoptotic protein Mcl-1S (short chain), suggesting that these Bcl-2 family member proteins may play a role on arbitrating the apoptotic cell death. Caseamembrin C also induced the up-regulation of Fas ligand (FasL) expression, cleavage and activation of caspase-8 and caspase-9, Bid cleavage and activation of executor caspase-3. However, z-IETD-FMK (Z-Ile-Glu-Thr-Asp-fluoromethyl ketone, a selective caspase-8 inhibitor) almost completely inhibited caseamembrin C-induced Bid cleavage without any modification of caspase-9 activation, indicating that the extrinsic pathway of FasL/caspase-8/Bid cascade only played a minor role in the apoptotic signaling. Taken together, it is suggested that caseamembrin C-induced apoptosis is predominantly through the activation of intrinsic apoptosis pathways by causing the down-regulation of Bcl-2 and Bcl-xL expression, up-regulation of Mcl-1S protein and activation of caspase-9 and caspase-3.     

石榴皮多酚对人前列腺癌PC-3细胞增殖及凋亡的影响

目的探讨石榴皮多酚对前列腺癌PC-3细胞株增殖和凋亡的影响。方法采用MTT法测定不同质量浓度组石榴皮多酚作用不同时间对PC-3细胞生长的影响,应用流式细胞仪检测石榴皮多酚作用72h后PC-3细胞的周期时相变化及凋亡情况。结果石榴皮多酚明显抑制PC-3细胞的生长,抑制效应呈时间依赖型和浓度依赖型。流式细胞仪检测结果显示,石榴皮多酚可将PC-3细胞阻滞于G1期,并诱导PC-3细胞凋亡。结论石榴皮多酚在体外对前列腺癌PC-3细胞株有明显的生长抑制和诱导凋亡的作用。     

Endocytosis of titanium dioxide nanoparticles in prostate cancer PC-3M cells

Nanotechnology has introduced many exciting new tools for the treatment of human diseases. One of the obstacles in its application to that end is the lack of a fundamental understanding of the interaction that occurs between nanoparticles and living cells. This report describes the quantitative analysis of the kinetics and endocytic pathways involved in the uptake of anatase titanium dioxide (TiO(2)) nanoparticles into prostate cancer PC-3M cells. The experiments were performed with TiO(2) nanoconjugates: 6-nm nanoparticles with surface-conjugated fluorescent Alizarin Red S. Results obtained by flow cytometry, fluorescence microscopy, and inductively coupled plasma-mass spectrometry confirmed a complex nanoparticle-cell interaction involving a variety of endocytic mechanisms. The results demonstrated that a temperature, concentration, and time-dependent internalization of the TiO(2) nanoparticles and nanoconjugates occurred via clathrin-mediated endocytosis, caveolin-mediated endocytosis, and macropinocytosis. FROM THE CLINICAL EDITOR: The interaction and uptake of TiO(2) nanoparticles (6-nm) with prostate PC-3M cells was investigated and found to undergo temperature, time, and concentration dependent intracellular transport that was mediated through clathrin pits, caveolae, and macropinocytosis. These results suggest that nanoparticles may widely permeate through tissues and enter almost any active cell through a variety of biological mechanisms, posing both interesting opportunity and possible challenges for systemic use.     

Induction of apoptotic cell death by a ceramide analog in PC-3 prostate cancer cells

Ceramide analogs are potential chemotherapeutic agents. We report that a ceramide analog induces apoptosis in human prostate cancer cells. The ceramide analog induced cell death through an apoptotic mechanism, which was demonstrated by DNA fragmentation, the cleavage of poly ADP ribose polymerase (PARP), and a loss of membrane asymmetry. Treating the cells with ceramide analog resulted in the release of various proapoptotic mitochondrial proteins including cytochrome c and Smac/DIBLO into the cytosol, and a decrease in the mitochondrial membrane potential. In addition, the ceramide analog decreased the phospho-Akt and phospho-Bad levels. The expression of the antiapoptotic Bcl-2 decreased slightly with increasing Bax to Bcl-2 ratio. These results suggest that the ceramide analog induces apoptosis by regulating multiple signaling pathways that involve the mitochondrial pathway.     

Oxidized low-density lipoprotein-induced apoptosis is attenuated by insulin-activated phosphatidylinositol 3-kinase/Akt through p38 mitogen-activated protein kinase

1. The aim of the present study was to investigate whether p38 mitogen-activated protein kinase (p38 MAPK) is involved in oxidized low-density lipoprotein (oxLDL)-induced apoptosis of human umbilical vein endothelial cells (HUVECs). We also sought to determine whether this apoptosis is regulated by the phosphatidylinositol 3-kinase (PI3K)/Akt pathway. 2. Low-density lipoprotein was oxidized with CuSO4 and used as oxLDL. Using HUVEC, we determined whether LDL/oxLDL induces apoptosis by DNA fragmentation and the cell cycle distribution (SubG1 method). The mechanism and activation of p38 MAPK and Akt were determined by western blot analysis. 3. The results showed that oxLDL induced DNA fragmentation, whereas cell cycle distribution showed that it also significantly increased the rate of cell death compared with the LDL group. SB203580 significantly inhibited cell death induced by oxLDL, as did the administration of insulin. Western blot analysis showed the activation of p38 MAPK by oxLDL, but not with LDL. It was found that Akt was activated in the presence of insulin. In the presence of either SB203580 or insulin, activation of p38 MAPK was significantly inhibited compared with stimulation by oxLDL alone. However, application of both insulin and wortmannin resulted in no significant difference compared with HUVEC stimulated by oxLDL only. 4. The results showed that apoptosis in HUVEC can be induced by oxLDL and involves p38 MAPK. It was also demonstrated that insulin inhibited oxLDL-induced apoptosis and may inhibit the activation of p38 MAPK through the PI3K/Akt pathway.     

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) alters the regulation and posttranslational modification of p27kip1 in lipopolysaccharide-activated B cells.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) alters B-cell differentiation, as evidenced by a marked decrease in immunoglobulin M (IgM) secretion and in the number of antibody-forming cells (AFC) induced by antigenic stimulation. The objective of the present studies was to evaluate the effect of TCDD on the level of p27kip1, a cyclin-dependent kinase inhibitor that is a critical regulator of cellular differentiation. In the well-characterized B-cell line, CH12.LX, a modest decrease in p27kip1 was observed during the initial 24-h post-LPS (lipopolysaccharide) activation, which then gradually increased above background at 48 and 72 h. Conversely, in the presence of TCDD, p27kip1 was not induced and remained unchanged from LPS unstimulated cells throughout the entire 72-h period post-LPS activation. In addition, Western blotting revealed that TCDD treatment altered the profile of p27kip1 migration as compared to the LPS-activated control. Time-of-addition studies demonstrated that the greatest sensitivity of p27kip1 to TCDD treatment occurred within the initial 24-h post-LPS activation. Interestingly, LPS-induced Ig kappa light chain and IgM secretion also exhibited the greatest period of sensitivity (i.e., inhibition) to TCDD during the first 24-h post-LPS activation. In addition, TCDD markedly suppressed the LPS-induced differentiation of CH12.LX cells into IgM secreting AFC, with a modest but cumulative effect on cell proliferation over a 72-h period. Collectively, these findings show that TCDD altered the cellular concentration and posttranslational modification of p27kip1 in this activated B-cell line model, which occurred concomitantly with altered B-cell differentiation and suggests that cyclin-dependent kinase inhibitors may be an important intracellular target in TCDD-mediated inhibition of B-cell differentiation.     

2β(3羟丙氧基)骨化三醇对人肝癌细胞周期阻滞及P~(27kip1)蛋白的诱导表达

目的探讨2β(3羟丙氧基)骨化三醇(ED-71)诱导人肝癌细胞HepG2生长抑制和细胞周期G1阻滞,及对抑癌基因P27kip1表达的影响。方法培养HepG2,应用四甲基偶氮唑盐(MTT)比色法观察ED-71对HepG2的生长抑制作用,流式细胞术分析细胞周期,以Western-blot检测HepG2细胞中P27kip1蛋白的表达水平。结果ED-71处理后HepG2的生长缓慢,细胞生长受到明显抑制。细胞阻滞于G1期(80.6±2.6,48.7±3.0,P<0.05),P27kip1蛋白表达水平增强(0.11±0.06,0.67±0.08,P<0.05)。结论ED-71抑制人肝癌细胞株HepG2的生长,诱导人肝癌细胞分化,使细胞阻滞于G1期,可能与ED-71诱导人肝癌细胞中抑癌基因P27kip1蛋白的表达有关。     

Induction of cell cycle-dependent cytotoxicity and apoptosis by new heterodinucleoside phosphate dimers of 5-fluorodeoxyuridine in PC-3 human prostate cancer cells

Fluorodeoxyuridine (5-FdUrd) is an antineoplastic agent with clinical activity against different types of solid tumours. To enhance the effectiveness of this drug, we have synthesised new heterodinucleoside phosphate dimers of 5-FdUrd. These dimers were compared to 5-FdUrd for their cytotoxic effect and the cell cycle dependence of cytotoxicity, as well as for their capacity to induce apoptosis and inhibit thymidylate synthetase (TS) in androgen-independent human PC-3 prostate tumour cells. Incubation of the cells with the dimers N(4)-palmitoyl-2'-deoxycytidylyl-(3'-->5')-5-fluoro-2'-deoxyuri din e (dCpam-5-FdUrd) and 2'-deoxy-5-flourouridylyl-(3'-->5')-2'-deoxy-5-fluoro-N(4)-octa decylc ytidine (5-FdUrd-5-FdC18) resulted in a marked cytotoxicity with IC(50) values of 4 microM, similar to 5-FdUrd. In contrast to 5-FdUrd, 100% toxicity was achieved with concentrations of 100-200 microM 5-FdUrd-5-FdC18. Flow cytometric analysis revealed an increase in the cell population in S-phase after treatment with 5-FdUrd, 5-FdUrd-5-FdC18, and dCpam-5-FdUrd from 36 to 63%, 50%, and 77%, respectively. dCpam-5-FdUrd was more potent than 5-FdUrd in arresting the cell cycle. Significant S-phase arrest was indicated by a decreased proportion of cells in G1- and G2/M-phases. Cell cycle arrest and inhibition of cell proliferation were followed by apoptosis, as shown by a 6- to 8-fold increased binding of Apo2.7 antibody, a 9- to 11-fold increase in caspase-3 activity, DNA fragmentation, and by cell morphology showing the appearance of apoptotic bodies. Importantly, 5-FdUrd-5-FdC18 increased the number of apoptotic cells to 160% compared to 5-FdUrd under the same conditions. As with 5-FdUrd, the two dimers also inhibited TS in a time- and concentration-dependent manner, although requiring 100-fold higher concentrations. In conclusion, dCpam-5-FdUrd and 5-FdUrd-5-FdC18 exert stronger cytotoxicity and induce more S-phase arrest and apoptosis than does 5-FdUrd in PC-3 cells, suggesting their potential role in the treatment of human prostate cancer.     

基于ROS/PI3K/Akt/mTOR信号通路探讨玫瑰花甲醇提取物对前列腺癌PC-3细胞凋亡的影响

目的：探讨玫瑰花甲醇提取物（RE）对前列腺癌PC-3细胞增殖和凋亡的影响及潜在作用机制。方法：采用CCK8法检测不同浓度RE对PC-3细胞增殖的影响;采用Hoechst染色法和Annexin V/PI双染法检测细胞凋亡;DCFH-DA检测细胞ROS水平;Western blot法检测Bax、Bcl-2、cleaved caspase-3、Cyt-C、PI3K、p-PI3K、Akt、p-Akt、mTOR、p-mTOR的蛋白表达。结果：RE呈浓度依赖性抑制前列腺癌PC-3细胞增殖,24 h和48 h后的IC₅₀值分别为31.30 mg·mL^-1和16.76 mg·mL^-1;RE能显著诱导PC-3细胞凋亡（P<0.05,P<0.01）,且呈现浓度依赖性;RE可显著提高PC-3细胞ROS水平（P<0.05,P<0.01）,且具有浓度依赖性;RE能显著上调PC-3细胞Bax、cleaved caspase-3、Cyt-C的蛋白表达及Bax/Bcl-2的比值（P<0.05,P<0.01）,显著下调Bcl-2、p-PI3K、p-Akt、p-mTOR的蛋白表达（P<0.05,P<0.01）,以上均呈现浓度依赖性。结论：本研究表明RE在体外有明显抑制前列腺癌细胞PC-3的增殖作用,并可能通过调控ROS/PI3K/Akt/mTOR信号通路诱导其凋亡,研究结果可为玫瑰花及其组方临床治疗前列腺癌提供实验依据。