Secreted frizzled-related protein 4 inhibits proliferation and metastatic potential in prostate cancer

BACKGROUND: Secreted frizzled-related proteins (sFRP4) inhibits Wnt signaling and thus cellular proliferation in androgen-independent prostate cancer cells in vitro. However, increased expression of membranous sFRP4 is associated with a good prognosis in human localized androgen-dependent prostate cancer, suggesting a role for sFRP4 in early stage disease. Here, we investigated the phenotype of sFRP4 overexpression in an androgen-dependent prostate cancer model. METHODS: An sFRP4-overexpressing androgen-dependent (LNCaP) prostate cancer model was established to assess changes in cellular proliferation, the expression, and subcellular localization of adhesion molecules and cellular invasiveness, and compared with the findings in sFRP4-overexpressing androgen-independent cells (PC3). RESULTS: sFRP4 overexpression in both cell line models resulted in a morphologic change to a more epithelioid cell type with increased localization of beta-catenin and cadherins (E-cadherin in LNCaP, N-cadherin in PC3) to the cell membrane. Functionally, sFRP4 overexpression was associated with a decreased rate of proliferation (P = 0.0005), decreased anchorage-independent growth (P < 0.001), and decreased invasiveness in PC3 cells (P < 0.0001). Furthermore, increased membranous sFRP4 expression was associated with increased membranous beta-catenin expression (P = 0.02) in a cohort of 224 localized human androgen-dependent prostate cancers. CONCLUSIONS: These data suggest that sFRP4 is an inhibitor of prostate cancer growth and invasion in vitro independent of androgen receptor (AR) signaling with correlative evidence in human androgen-dependent disease suggesting similar changes in the clinical setting. Consequently, potential therapeutic strategies to modulate Wnt signaling by sFRP4 will be relevant to both localized androgen-dependent prostate cancer and advanced metastatic disease.     

Polymorphism of cytochrome P450 2B6 and prostate cancer risk: A significant association in a Japanese population

Objectives:   To explore whether Lys262Arg polymorphism of the Cytochrome P450 2B6 (CYP2B6) gene could act as a genetic marker for prostate cancer risk among Japanese men.
Methods:   A total of 350 patients with sporadic prostate cancer and 328 controls were examined. A single nucleotide polymorphism with non-synonymous amino acid change located at Lys262Arg of the CYP2B6 gene was genotyped using a TaqMan assay.
Results:   The frequency of the Arg/Arg genotype among prostate cancer patients was significantly higher than that among the controls ( P  = 0.027). The frequency of the G allele of the Lys262Arg polymorphism was also significantly higher in prostate cancer patients than in the controls (30.4% vs 24.8%, P  = 0.025). Patients with the Lys/Arg plus Arg/Arg genotypes carried a low Gleason score more frequently than those with the Lys/Lys genotype ( P  = 0.042). The frequency of the G allele of the Lys262Arg polymorphism was significantly higher in the low Gleason score group than that in the high Gleason score group (34.3% vs 26.8%, P  = 0.038).
Conclusions:   Lys262Arg polymorphism of the CYP2B6 gene may be a genetic marker for evaluating the risk of sporadic prostate cancer in native Japanese men.     

靶向TRPV6的siRNA对前列腺癌LNCaP细胞抑制作用的体外研究

目的:运用RNA干扰(RNAi)技术阻断前列腺癌LNCaP细胞中瞬时感受器电位离子通道蛋白V亚家族6(TRPV6)基因的表达,探讨TRPV6基因沉默对LNCaP细胞增殖、细胞周期及凋亡的影响。方法:针对TR-PV6基因,构建2条小干扰RNA(siRNA)序列;在脂质体介导下转染前列腺癌LNCaP细胞,用RT-PCR测定TRPV6mRNA的表达;MTT法和流式细胞技术测定siRNA对LNCaP细胞增殖、细胞周期及凋亡的影响。结果:两条siRNA序列均能有效地阻断LNCaP细胞中TRPV6基因在mRNA水平上的表达(P<0.01),且mRNA表达随着转染时间的延长而减少,转染72h后TRPV6mRNA的表达减少至对照组的27%和23%;siRNA转染能显著抑制LNCaP细胞增殖,转染48h细胞增殖抑制率最高,分别为34.53%和29.32%,与转染24h和72h比较有统计学意义(P<0.05);转染48h后,siRNA转染组G0～G1期细胞增多,S期细胞数量明显减少,与空白对照组及阴性对照组相比有统计学差异(P<0.01);siRNA转染组细胞的凋亡率分别为14.45%和12.73%,显著高于空白对照组及阴性对照组3.78%和5.22%(P<0.05)。结论:针对TRPV6的siRNA在体外能有效地抑制LNCaP细胞TRPV6mRNA的转录,同时能够抑制前列腺癌LNCaP细胞增殖,使细胞周期出现G0/G1期阻滞,细胞凋亡率显著增加。     

姜黄素通过caspase依赖的凋亡途径抑制LNCaP细胞生长

目的探讨姜黄素诱导雄激素依赖性前列腺癌LNCaP细胞凋亡过程中caspase途径的作用。方法应用CCK8法检测不同浓度（10、20、30、40、50、60μmol/L）姜黄素作用LNCaP细胞12、24、48h后的细胞生长抑制情况。应用Annexin V/PI双染法检测不同浓度（10、20、40μmol/L）姜黄素作用LNCaP细胞24h后的细胞凋亡情况。应用Western blot检测姜黄素作用LNCaP细胞24h后Bax、Bcl-2、Cleaved-caspase-3、Cytochrome C凋亡相关蛋白的变化。结果姜黄素对LNCaP细胞的生长有明显的抑制作用,且呈时间-剂量依赖性;流式细胞术结果显示姜黄素能诱导LNCaP细胞凋亡,10、20、40μmol/L姜黄素作用LNCaP细胞24、48h后细胞凋亡率分别为（6.01±0.95）%、（15.46±1.13）%、（26.13±1.56）%和（11.19±1.74）%、（25.80±2.47）%、（38.72±2.89）%,且呈时间-剂量依赖性（P〈0.05）;同时姜黄素能够降低LNCaP细胞中Bcl-2的表达,上调Bax、Cytochrome C、Cleavedcaspase-3的表达。结论姜黄素能抑制LNCaP细胞的生长,其作用可能是通过线粒体途径诱导其凋亡。     

人工合成小分子RNA对前列腺癌细胞周期及增殖的影响

目的 研究人工合成的dsP21-555对前列腺癌细胞株PC-3和LNCaP细胞周期和增殖的影响。方法 合成dsP21-555（实验组）和dsControl（阴性对照组）,分别转染至PC-3和LNCaP。使用Real-time PCR及Western blotting分别检测分析前列腺癌细胞转染后的p21mRNA及p21蛋白的表达情况。流式细胞术检测细胞周期分布,使用MTT实验及集落形成实验检测细胞的活力及增殖能力。结果 转染dsP21-555后PC-3和LNCaP细胞中的p21 mRNA水平分别上调至2.90倍(P<0.01)和2.05倍(P<0.01)。Western blotting实验结果符合这一趋势。流式细胞术检测显示,转染dsP21-555后,在S期和G2/M期的细胞比例下降,在G0/G1期的细胞比例则增加。MTT实验显示,与dsControl组相比,转染dsP21-555后,PC-3和LNCaP细胞的活力明显降低。集落形成实验显示,dsP21-555组的集落的数量较少,细胞增殖能力降低。结论 人工合成的dsP21-555能明显激活前列腺癌细胞中p21基因的表达,并显著抑制前列腺癌细胞周期的进展和增殖。     

抗雄激素条件下癌相关成纤维细胞对前列腺癌LNCaP细胞增殖的影响

目的体外研究抗雄激素条件下癌相关成纤维细胞(cancer associated fibroblasts,CAFs)对雄激素依赖性前列腺癌LNCaP细胞增殖能力的影响。方法体外原代培养源于人前列腺癌基质的CAFs,并用抗雄激素制剂氟他胺(Flutamide)进行处理,制备出条件培养液CAFs-Flu-CM。CAFs原代培养液制备出另一条件培养液CAFs-CM作为对照研究。观察LNCaP细胞在RPMI-1640培养液、CAFs-CM培养液和CAFs-Flu-CM培养液中的生长增殖能力和差异性。结果与RPMI-1640培养液培养的LNCaP细胞相比,10-6mol/L Flutamide可抑制其生长(76.55±7.1 vs 114.51±9.8,P<0.05);浓度为0.75g/L的CAFs-CM却可显著提高LNCaP细胞的增殖能力(237.26±18.3 vs 114.51±9.8,P<0.05)。经10-6mol/L Flutamide处理后,CAFs-Flu-CM刺激LNCaP细胞增殖的能力明显减弱(32.73±5.6 vs 237.26±18.3,P<0.05)。结论源于人前列腺癌基质的CAFs可提高LNCaP细胞的增殖能力,但经抗雄制剂处理后,CAFs功能受到干扰,刺激LNCaP细胞增殖的能力明显减弱。联合靶向CAFs的肿瘤治疗策略可能会提高前列腺癌内分泌治疗的有效性,可作为临床治疗前列腺癌新的靶点。     

γ-干扰素对前列腺癌细胞粘附和侵袭能力影响的初步研究

目的：探讨γ-干扰素对前列腺癌细胞粘附和侵袭行为的影响。方法：用纤维粘连蛋白和层粘连蛋白处理细胞培养板，检测γ-干扰素对前列腺癌细胞系LNCaP和PC-3粘附作用的影响；用Transwell小室，以Matrigel和纤维粘连蛋白构建基底膜，检测γ-干扰素对前列腺癌细胞侵袭人工基底膜能力的影响；应用Western-blot法检测γ-干扰素对前列腺癌细胞膜粘连蛋白-2（annexin-2）表达的影响。结果：γ-干扰素未处理的两种人前列腺癌细胞系细胞LNCaP、PC-3粘附率分别为46％和40％，γ-干扰素处理的两种细胞系细胞LNCaP、PC-3粘附率分别为21％和23％，同种细胞系γ-干扰素处理组与未处理组间差异有显著性（P均〈0．05）。在相同细胞系γ-干扰素处理组较未处理组前列腺癌细胞24h侵袭能力明显降低（P均〈0．05）。Western印迹结果表明γ-干扰素可显著抑制annexin-2蛋白的表达（P〈0．05）。结论：γ-干扰素可能通过下调annexin-2的表达来抑制前列腺癌细胞的粘附和侵袭。     

Protein tyrosine phosphatase PTP1B is involved in neuroendocrine differentiation of prostate cancer

BACKGROUND: Prostate cancer (PC) contains a minor component of neuroendocrine (NE) cells that may stimulate androgen-independent growth of the tumor. The mechanism of neuroendocrine differentiation remains unknown. METHODS: The expression of PTP1B, a protein tyrosine phosphatase, was studied in LNCaP cells induced to show neuroendocrine phenotype by androgen withdrawal. Wild-type PTP1B and its dominant-negative mutant were transfected into LNCaP cells to study their effects on neuroendocrine differentiation. In vivo expression of PTP1B in human prostate cancer was studied by immunohistochemistry. RESULTS: Androgen withdrawal of LNCaP cells led to increased expression of PTP1B with a corresponding increase in its tyrosine phosphatase activity. Overexpression of PTP1B in LNCaP cells led to neuroendocrine differentiation while expression of its dominant-negative mutant inhibited neuroendocrine differentiation. Immunohistochemical study showed that PTP1B was exclusively expressed in neuroendocrine cells of human prostate cancer tissue. CONCLUSION: Our findings suggest that PTP1B plays an important role in neuroendocrine differentiation, and therefore, may possibly be involved in the progression of prostate cancer.     

In vivo and in vitro studies of anticancer actions of alpha-TEA for human prostate cancer cells

BACKGROUND: Vitamin E analog, 2,5,7,8-tetramethyl-2R-(4R,8R, 12-trimethyltridecyl) chroman-6-yloxyacetic acid, referred to as alpha-TEA induces apoptosis in a variety of human cancer cells in cell culture and reduces tumor burden and metastases in preclinical animal models of breast and ovarian cancer. The goal of this study was to determine in vivo anticancer efficacy of alpha-TEA against human prostate cancer cells and identify mechanisms of action. METHODS: A PC-3-GFP xenograft model was used to assess the effects of alpha-TEA formulated in liposomes and administered orally on tumor burden and metastases. Tumor tissue was examined by immunohistochemical staining for percentage of cells undergoing apoptosis by TUNEL or cell proliferation by Ki-67. In vitro analyses of mechanisms employed western immunoblotting to examine effects of alpha-TEA-treatments in LNCaP and PC-3-GFP cells on levels of pro-survival and pro-death factors. Functional significance was determined using ectopically expressed constitutively active forms, inhibitors, or siRNA. RESULTS: alpha-TEA significantly reduced tumor burden and metastases, increased apoptosis and decreased proliferation of tumor cells (P < 0.05). alpha-TEA treatment of both LNCaP and PC-3-GFP cells in vitro reduced levels of pAkt1, pAkt2; FOXO1, c-FLIP(L) and survivin. Constitutively active Akt1, Akt2, c-FLIP or survivin reduced alpha-TEA-induced apoptosis. PI3K inhibitor enhanced apoptosis. Constitutively active FOXO1 enhanced alpha-TEA induced Fas ligand expression; whereas, FOXO1 siRNA reduced alpha-TEA induced Fas ligand expression. CONCLUSIONS: alpha-TEA is an effective anticancer agent for human prostate cancer cells. Downregulation of pro-survival and upregulation of pro-death factors play roles in alpha-TEA-induced apoptosis.     

CYP4Fs expression in rat brain correlates with changes in LTB4 levels after traumatic brain injury

Cytochrome P450 (CYP) 4Fs constitute a subgroup of the cytochrome P450 superfamily and are involved in cellular protection and metabolism of numerous molecules, including drugs, toxins, and eicosanoids. CYP4Fs are widely distributed in rat brain with each isoform having a unique distribution pattern throughout different brain regions. The present study shows that traumatic brain injury (TBI) triggers inflammation and elicits changes in mRNA expression of CYP4Fs in the frontal and occipital lobes and the hippocampus. At 24 h post-injury, almost all CYP4F mRNA expression is suppressed compared with sham control throughout these three regions, while at 2 weeks post-injury, all CYP4F mRNAs increase, reaching levels higher than those at 24 h post-injury or uninjured controls. These changes in CYP4F levels inversely correlate with levels of leukotriene B4 (LTB4) levels in the brain following injury at the same time points. TBI also causes changes in CYP4F protein expression and localization around the injury site. CYP4F1 and CYP4F6 immunoreactivity increases in surrounding astrocytes, while CYP4F4 immunoreactivity shifts from endothelia of cerebral vessels to astrocytes.     

Decreased expression of cellular prostatic acid phosphatase increases tumorigenicity of human prostate cancer cells

PURPOSE: Understanding cell proliferation regulation in hormone refractory prostate cancer may provide answers for novel solutions. Protein tyrosine phosphatases have been thought to have key roles in regulating cell proliferation and be involved in oncogenesis, although to our knowledge their functional roles in human prostate cancer remain unknown. Human prostatic acid phosphatase (PAcP), a major phosphatase in prostate epithelium, has been shown to function as a neutral protein tyrosine phosphatase in these cells. We evaluated the biological significance of cellular prostatic acid phosphatase expression in human prostate cancer cells. MATERIALS AND METHODS: Immunohistochemical testing of human prostate cancer archival specimens was done to evaluate the expression of cellular PAcP. Immunoprecipitation and immunoblotting were performed to determine cellular PAcP and SH2 domain-bearing tyrosine phosphatase-1 levels as well as tyrosine phosphorylation of c-ErbB-2/neu in different human prostate cancer cells. The biological behavior of LNCaP derivative sublines was characterized in vitro and in vivo by soft agar analysis and xenograft animal inoculation. RESULTS: Immunohistochemical staining of human prostate clearly showed that cellular levels of PAcP significantly decreases in prostate cancer cells (p <0.001). The results of biochemical characterization revealed that the cellular level of PAcP but not SHP-1, another differentiation associated protein tyrosine phosphatase, consistently correlated negatively with the growth of several human prostate cancer cell lines. Reintroducing cellular PAcP activity in prostate cancer cells by PAcP complementary DNA transfection resulted in decreased tyrosine phosphorylation of c-ErbB-2/neu, decreased proliferation rates in culture as well as decreased anchorage independent growth in soft agar. The xenograft animal model demonstrated that a higher tumor growth rate as well as larger size is associated with a lower level of cellular PAcP. CONCLUSIONS: Cellular PAcP can down-regulate prostate cancer cell growth, at least partially by dephosphorylating c-ErbB-2/neu. Therefore, decreased cellular PAcP expression in cancer cells may be involved in prostate cancer progression.     

Osteoblasts produce soluble factors that induce a gene expression pattern in non-metastatic prostate cancer cells, similar to that found in bone metastatic prostate cancer cells

BACKGROUND: Progressive prostate cancer typically metastasizes to bone where prostate cancer cells gain an osteoblast-like phenotype and induce osteoblastic metastases through unknown mechanisms. To investigate the biology of prostate cancer skeletal metastases, we compared gene expression between the non-metastatic LNCaP cell line and its derivative cell line C4-2B that metastasizes to bone. METHODS: Total RNA from LNCaP and C4-2B cell lines was isolated and used to probe membrane-based gene arrays (Comparison 1). Additionally, LNCaP cells were incubated in the absence or presence of conditioned media (CM) from a human osteoblast-like cell line (HOBIT) and total RNA from these cells was used to probe gene arrays (Comparison 2). Differential expression of genes was confirmed by RT-PCR. RESULTS: Of the 1,176 genes screened, 35 were differentially expressed between LNCaP and C4-2B cells (Comparison 1). HOBIT-CM induced differential expression of 30 genes in LNCaP cells (Comparison 2). Interestingly, 19 genes that were differentially expressed in C4-2B vs. LNCaP also displayed a similar expression pattern in LNCaPs grown in HOBIT-CM. These genes are primarily involved in motility, metabolism, signal transduction, tumorigenesis, and apoptosis. CONCLUSIONS: These results suggest that osteoblasts produce soluble factors that contribute to the progression of prostate cancer skeletal metastases, including their transition to an osteoblast-like phenotype. Additionally, these data provide targets to explore for further investigations towards defining the biology of skeletal metastases.     

Monomethylated selenium inhibits growth of LNCaP human prostate cancer xenograft accompanied by a decrease in the expression of androgen receptor and prostate-specific antigen (PSA)

OBJECTIVES: Epidemiological studies and prevention trials suggest selenium is a promising preventive agent for prostate cancer. Selenium-containing compounds inhibited the growth of prostate cancer cell lines including androgen sensitive LNCaP and androgen insensitive DU145 and PC3 cells in vitro. Previous study revealed a novel mechanism of selenium action in which selenium (methylseleninic acid (MSA)) markedly reduced androgen receptor (AR) signaling in prostate cancer cells, suggesting that selenium might act as an antiandrogen, which could serve as a therapeutic agent for prostate cancer. In this study, we tested whether selenium (methylselenocysteine (MSC)) affects tumor growth of human prostate cancer cells by targeting AR signaling in vivo. METHODS: Prostate tumor xenografts were established in nude mice by co-inoculating LNCaP cells with Matrigel. The mice-bearing tumors were treated with or without MSC (100 microg/mouse/day) via intraperitoneal injection for 2 weeks. The effect of MSC on tumor growth, AR, and prostate-specific antigen (PSA) expression was examined. RESULTS: Methylselenocysteine (MSC) significantly inhibited LNCaP tumor growth (P < 0.05). AR expression in tumor tissues and serum PSA levels were considerably decreased in MSC-treated mice compared to the vehicle controls. CONCLUSIONS: Pharmacological dose of MSC inhibits the growth of LNCaP human prostate cancer in vivo accompanied by a decrease in the expression of AR and PSA. These findings suggest that selenium (MSC) can serve as a therapeutic agent aimed at disruption of AR signaling for prostate cancer.     

Antitumor activity and downregulation of pro-angiogenic molecules in human prostate cancer cells by a novel thiazolidione compound

BACKGROUND: Current treatments for prostate cancer are effective in many patients with locally advanced disease, but many of these patients eventually have recurrence. It is therefore important to develop alternative therapeutic agents with improved efficacy and tolerability. We recently identified a synthetic thiazolidin compound, 5-(2,4-dihydroxybenzylidene)-2-(phenylimino)-1,3-thiazolidione (DBPT), that induces apoptosis in human colon cancer cells, independent of p53 and P-glycoprotein status. Here, we investigated the antitumor properties and mechanisms of action of this compound in human prostate cancer cell lines. METHODS: The effect of DBPT on cell-cycle progression and apoptosis in LNCaP and DU145 cells was examined by flow cytometry and Western blotting. The effect of DBPT on pro-angiogenic molecules was analyzed by Western blotting and by an enzyme-linked immunosorbent assay. RESULTS: DBPT inhibited the growth of LNCaP and DU145 cells with 50% inhibitory concentrations ranging from 1.6 to 5.9 microM. Treating LNCaP and DU145 cells with DBPT led to a time-dependent cell-cycle arrest in the G(2)/M phase and increased levels of G(2)/M checkpoint proteins, such as cyclin B1, cdc25C, phosphorylated histone H(3), and MPM-2. DBPT induced the phosphorylation of Bcl-xL and Bim, and induced apoptosis, as evidenced by cleavage of caspase and poly (ADP-ribose) polymerase. DBPT also effectively induced apoptosis in Bcl-2-overexpressing DU145 cells. Furthermore, DBPT decreased hypoxia-inducible factor 1 alpha and vascular endothelial growth factor expression in LNCaP cells under both normoxia and hypoxia. CONCLUSIONS: DBPT can suppress proliferation, induce apoptosis, and down regulate pro-angiogenic molecules in prostate cancer cells, and might be useful in treating prostate cancer.     

睾酮对前列腺癌LNCaP细胞雄激素反应性基因表达的影响

目的检测睾酮作用下雄激素依赖性前列腺癌细胞LNCaP中雄激素反应性基因（ARGs)的表达情况。方法检测不同浓度的睾酮对雄激素依赖性前列腺癌细胞LNCaP增殖的影响，采用基因芯片确定LNCaP细胞中受睾酮调控的基因。结果低浓度的睾酮促进LNCaP细胞的生长，并呈剂量依赖性，相反较高浓度的睾酮能够抑制LNCaP的增殖。在96个与前列腺癌有关的基因中，受睾酮刺激有19个基因表达上调，8个基因表达下调。结论睾酮诱导的雄激素反应性基因在前列腺癌的发展中起非常重要的作用，基因芯片有助于高通量分析基因表达水平的变化，为前列腺癌的研究提供了非常理想的工具。     

Prostate cancer cells generated during intermittent androgen ablation acquire a growth advantage and exhibit changes in epidermal growth factor receptor expression

BACKGROUND: Intermittent androgen ablation is a palliative treatment option for advanced prostate cancer which is associated with less side effects, improved quality of life of patients, and reduced costs. Regulation of growth and survival of prostate cancer cells during intermittent androgen withdrawal has not been studied in appropriate models yet. METHODS: Two cycles of androgen withdrawal and supplementation were performed in human prostate cancer cells LNCaP in vitro. Proliferation of prostate cancer cell sublines established after intermittent androgen withdrawal was assessed in the absence or presence of epidermal growth factor (EGF) by protein determination. Cell cycle was analyzed with a flow cytometer. EGF was measured in the supernatants of LNCaP sublines with a commercial ELISA. EGF receptor mRNA and protein were determined by real-time PCR and Western blot, respectively. RESULTS: Basal proliferation rate of all newly generated LNCaP sublines increased over that of the parental LNCaP cell line. The highest stimulation of proliferation by exogenous EGF was observed in parental LNCaP cells. In each LNCaP derivative established during intermittent androgen withdrawal, the percentage of cells in the S phase of cell cycle was higher than that in parental LNCaP cells. EGF levels did not increase during intermittent androgen ablation. The expression of EGF receptor protein decreased following each cycle of androgen ablation and increased subsequently after androgen supplementation. EGF receptor (EGFR) mRNA was regulated in a similar manner in LNCaP derivatives established during the second cycle of intermittent withdrawal. CONCLUSIONS: Changes in the expression of the EGF receptor occur during intermittent androgen ablation but they cannot be solely responsible for increased basal proliferation. Alternatively, other ligands and receptors of the EGF system may become overexpressed during prolonged withdrawal and supplementation of androgenic hormones in prostate cancer therapy.     

苦参碱对前列腺癌细胞增殖及雄激素受体功能的抑制作用

目的:探讨苦参碱(matrine)对雄激素依赖性前列腺癌细胞株(LNCaP)的增殖及雄激素受体(androgen re-ceptor,AR)表达的抑制作用。方法:分别用0.5、1.0、1.5、2.0、3.0g/L浓度的苦参碱作用于LNCaP细胞12、24、36h后MTT法检测细胞生长活性;台盼蓝拒染法测定细胞生长曲线;24h后流式细胞仪测定细胞周期变化;24h后Western印迹法检测细胞内AR的表达。结果:苦参碱能抑制LNCaP细胞的生长,呈剂量与时间依赖性,不同浓度苦参碱组之间与不同作用时间组之间的差异均有显著性意义(P<0.01)。苦参碱诱导LNCaP细胞出现剂量依赖性G2/M期阻滞(P<0.01);细胞内AR的表达随苦参碱剂量依赖性减少(P<0.01)。结论:苦参碱通过下调细胞内AR表达和阻滞细胞周期进展来抑制LNCaP细胞的体外生长。     

双氢睾酮对前列腺癌LNCaP细胞线粒体呼吸链酶学变化的影响

目的 观察双氢睾酮对人前列腺癌细胞LNCaP细胞株线粒体呼吸链酶学变化的影响,探讨双氢睾酮引起LNCaP线粒体内酶学变化的作用机制.方法 获得雄激素依赖性细胞(LNCaP)细胞株,进行细胞培养,获得稳定生长及传代的细胞株.不同浓度的雄激素受体激动剂双氢睾酮作用于培养的LNCaP细胞株;不同时间点提取干预措施下的LNCaP线粒体;检测并比较不同时间点、不同浓度药物作用下LNCaP线粒体呼吸链酶学的变化和差异.结果 DHT作用于LNCaP细胞后,线粒体蛋白的含量显著增加(P＜0.05),但SDH、NADH、COX的含量显著下降(P＜0.05),各个指标在不同的时间点上下降的程度有所差异.结论 双氢睾酮可引起LNCaP线粒体内蛋白的表达量升高,促进LNCaP的增殖.