锤头型核酶特异性阻断雄激素受体表达对前列腺癌细胞生长的影响

目的：探讨核酶阻断雄激素受体（AR）基因表达治疗前列腺癌的可能性。方法：在脂质体介导下，锤头型抗雄激素受体核酶表达载体转染前列腺癌细胞，采用逆转录－聚合酶链反应（RT－PCR）检测ARmRNA，四甲基偶氮唑盐（MTT）法检测细胞增殖活性，流式细胞仪（FCM）检测细胞周期时相，原位末端转移酶标记法检测细胞凋亡。结果：核酶表达载体转染1－5d后，前列腺癌细胞AR mRNA水平降低32．6％－40．7％（P＜0．05），细胞生长抑制率18．28％－35．34％（P＜0．05），细胞周期阻滞于G2／M期，诱导细胞凋亡，细胞凋亡比率增加20．70％（P＜0．01）。结论：应用核酶特异性切割ARmRNA，能有效阻断AR基因的表达，诱导前列腺癌细胞凋亡，有可能成为前列腺癌基因治疗的有效方法之一。     

miR-152对前列腺癌细胞株迁移和侵袭能力的影响

目的研究miR-152在前列腺癌、前列腺正常组织中的表达情况及其在前列腺癌细胞系中的作用。方法采用TaqMan荧光定量RT—PCR方法检测8例前列腺癌和8例前列腺正常组织的样本中miR-152的表达水平。运用Transwell细胞迁移实验及侵袭实验评估miR一152对前列腺细胞系PC-3和DU145细胞功能的影响。结果与正常前列腺组织相比,miR-152在前列腺癌组织中的表达水平显著下调（P〈0．05）。体外实验中上调miR152的表达可以显著降低前列腺癌细胞的迁移和侵袭能力（P〈O．05）。结论miR-152在前列腺癌中可作为一种肿瘤抑制因子,影响前列腺癌细胞的迁移和侵袭能力。     

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.     

Effects of gametogenetin-binding protein 2 on proliferation,invasion and migration of prostate cancer PC-3 cells

We aimed to assess the effects of gametogenetin-binding protein 2 (GGNBP2) on the proliferation, invasion and migration of prostate cancer PC-3 cells. PcDNA3-HisC-GGNBP2 was transfected to overexpress GGNBP2. Proliferation was tested by MTT assay, and migration and invasion were detected by Transwell assay. Cell cycle was detected by flow cytometry. The protein expressions of COX-2, cyclin D1, PI3K, Akt and p-Akt were detected by Western blot. A subcutaneous xenograft model of prostate cancer was established. Mice were randomly divided into three groups (n = 9) and intratumorally injected with pcDNA3-HisC-GGNBP2, pcDNA3-HisC and normal saline respectively. The xenograft tumour volume was measured every 3 days, and weight was measured after 2 weeks. After GGNBP2 overexpression, the proliferation, migration and invasion capacities of PC-3 cells decreased, and cell cycle was arrested in the G1 phase. The protein expressions of COX-2, cyclin D1, PI3K, Akt and p-Akt all reduced. The tumour volume and weight of pcDNA3-HisC-GGNBP2 group were significantly lower than those of pcDNA3-HisC group (p < .05). The proliferation capacity of GGNBP2-overexpressing prostate cancer cells is significantly attenuated, tumour growth is significantly inhibited, and cell cycle is arrested in the G1 phase. GGNBP2 overexpression affects the growth of castration-resistant prostate cancer via the PI3K/Akt signalling pathway.     

Intermediate cells in normal and malignant prostate epithelium express c-MET: implications for prostate cancer invasion

BACKGROUND: Analysis of keratin (K) expression discriminates luminal (K18) and intermediate (K5/18) cells in prostate carcinoma, while basal (K5/14) cells are absent. Intermediate cells have been proposed as targets of malignant transformation in prostate cancer and precursors of androgen-independent tumor progression. We demonstrate localization of hepatocyte growth factor (HGF) receptor c-MET in intermediate cells in both normal and malignant prostate epithelium. METHODS: Receptor localization was analyzed using triple staining for c-MET, K5, K14, and K18. The percentage of strongly c-MET positive cells was determined in 15 prostate cancer patients undergoing androgen-deprivation and 14 patients without neo-adjuvant treatment. Effects of HGF were investigated on prostate cancer cell line DU145. RESULTS: c-MET expression in non-malignant epithelium was strong in intermediate cells absent in differentiated cells, and heterogeneous in basal cells. In prostate cancer, intermediate cells displayed high c-MET levels coupled with mild expression in differentiated cells. During androgen-deprivation, 7.6% of tumor cells revealed high c-MET expression compared to 1.7% without treatment (P = 0.02). Matrigel penetration of DU145 was 8.2 +/- 1.7 mm(2) after HGF stimulation compared to 3.6 +/- 2.4 mm(2) in controls (P < 0.02). CONCLUSIONS: Intermediate cells in normal and malignant prostate epithelium express high c-MET levels, indicating that they are prone to stromal invasion in prostate carcinoma.     

大肠癌细胞增殖中HGF/SF作用的观察

目的研究肝细胞生长因子/离散因子(HGF/SF)在诱导大肠癌细胞增殖中的作用。方法采用W estern B lot方法,检测HGF的受体c-met在受检大肠癌细胞株Caco-2,Colo3 2 0中的表达;观察Caco-2,Colo3 2 0中HGF/SF活化p 4 2/p 4 4MAPK和p 3 8MAPK的动态变化;应用[3H]-TdR,MTT方法观察p 4 2/p 4 4MAPK和p 3 8MAPK传导通路阻滞剂PD 9 8 0 5 9和SB 2 0 3 5 8 0对HGF/SF诱导的大肠癌细胞增殖的抑制作用。结果(1)c-met在Caco-2和Colo3 2 0中有表达。(2)HGF/SF激活p 4 2/p 4 4MAPK,p 3 8MAPK:2 0 ng/mL的HGF/SF处理细胞,p 4 2/p 4 4MAPK磷酸化在1 0m in达高峰(2.2 8±0.0 1);p 3 8MAPK变化与之相似(2.2 5±0.0 1)。(3)HGF/SF诱导大肠癌细胞的DNA合成增加依赖于p 4 2/p 4 4MAPK的激活,在2 4 h时点分别以2 0 ng/m lHGF/SF,不同浓度(1μmol/L,5μmol/L,1 0μmol/L)的PD 9 8 0 5 9和SB 2 0 3 5 8 0处理细胞,HGF/SF使胸腺啶吸收增加(P<0.0 1);PD 9 8 0 5 9以浓度依赖性抑制胸腺啶的吸收(P<0.0 1)。(4)HGF促进Caco-2细胞的增殖,而PD 9 8 0 5 9对这种增殖有抑制作用。结论HGF激活大肠癌细胞Caco-2和Colo3 2 0中p 4 2/p 4 4MAPK和p 3 8MAPK;p 4 2/p 4 4MAPK参与HGF/SF诱导的大肠癌细胞Caco-2有丝分裂;HGF促进大肠癌细胞Caco-2增殖;HGF/SF和p 4 2/p 4 4MAPK在大肠癌细胞中发挥作用可能有细胞选择性。     

Toll like receptor-9 agonists stimulate prostate cancer invasion in vitro

BACKGROUND: Toll-like receptor 9 (TLR9) recognizes microbial DNA. In addition to immune cells, TLR9 expression has been detected in various cancer cells. We showed recently that TLR9 agonistic CpG-oligonucleotides (CpG-ODNs) induce matrix metalloproteinase-13 (MMP-13)-mediated invasion in TLR9-expressing (TLR9(+)) breast cancer cells. We investigated here TLR9 expression and function in human prostate cancer (CaP) cells. METHODS: TLR9 expression was detected with Western blotting and immunohistochemistry. Invasion was studied with Matrigel-assays. MMP-13 was assayed with ELISA. RESULTS: Human CaP cell lines and clinical samples exhibit various levels of TLR9 expression. Treatment of TLR9(+), but not TLR9(-) CaP cells with CpG-ODNs or bacterial DNA increased their invasion, which was inhibited with chloroquine. CpG-ODN-treatment also increased MMP-13 activity and neutralizing anti-MMP-13 antibody prevented CpG-ODN-induced invasion in TLR9(+) CaP cells. Estradiol up-regulated TLR9 expression in LnCaP cells. CONCLUSIONS: TLR9-mediated invasion may represent a novel mechanism through which infections promote prostate cancer.     

3-溴丙酮酸对前列腺癌PC-3细胞增殖、迁移及侵袭的影响

目的:观察3-溴丙酮酸(3-BrPA)对前列腺癌细胞PC-3增殖、迁移和侵袭能力的影响,并初步探讨其内在机制。方法:体外培养PC-3细胞,倒置显微镜下观察不同浓度3-BrPA对PC-3细胞形态学的影响;应用MTT法、细胞划痕和Transwell法检测不同浓度3-BrPA在不同时间段(24、48、72 h)对前列腺癌PC-3细胞增殖、迁移和侵袭的影响;应用Western印迹检测3-BrPA作用后各组PC-3细胞葡萄糖转运蛋白1(GLUT1)和基质金属蛋白酶14、9、2(MMP-14、MMP-9、MMP-2)蛋白表达的变化。结果:在一定浓度范围内,随着3-BrPA浓度的升高,细胞形态的改变愈明显。MTT结果表明,随着3-BrPA浓度的增加、作用时间延长PC-3细胞抑制率增大(P<0.01)。细胞划痕和Transwell细胞侵袭实验显示:与对照组相比,培养24 h后25、50、100μmol/L 3-BrPA浓度组细胞划痕迁移愈合率降低,细胞侵袭数目减少,且培养48 h与24 h相比,各组细胞迁移愈合率和侵袭细胞数目均降低,表明细胞体外迁移率和侵袭细胞数目与3-BrPA作用浓度、作用时间有关,具有剂量和时间依赖性(P<0.01)。Western印迹检测结果表明:与对照组相比,25、50、100μmol/L 3-BrPA浓度组中GLUT1、MMP-14、MMP-9、MMP-2蛋白表达量明显降低(P<0.01)。结论:糖酵解抑制剂3-BrPA降低PC-3增殖、迁移和侵袭能力,可能与下调GLUT1、MMP-14、MMP-9及MMP-2蛋白表达有关。     

Function of mutant and wild‐type plexinB1 in prostate cancer cells

BACKGROUND

Semaphorins act as chemotactic cues for cell movement via their transmembrane receptors, plexins. Somatic missense mutations in the plexinB1 gene coupled with overexpression of the protein frequently occur in prostate tumors, indicating a role for plexinB1 in the pathogenesis of prostate cancer. However, the effect of semaphorin/plexin signaling is highly context dependent and whether plexinB1 acts as an inducer or inhibitor of prostate tumor progression in this context is not known.

METHODS

The response of prostate cancer cell lines to plexinB1 activation was assessed in migration, invasion, proliferation and protein phosphorylation assays. Expression was assessed by quantitative RTPCR and immunoblotting.

RESULTS

Different prostate cancer cell lines respond to Sema4D (the ligand for plexinB1) in diverse ways. Activation of endogenous plexinB1 enhances migration, invasion and anchorage‐independent growth of LNCaP prostate cancer cells via activation of ErbB2 and Akt. In contrast, Sema4D‐stimulation decreased the motility and proliferative capacity of PC3 cells. LNCaP has a missense mutation (Thr1697Ala) in the plexinB1 gene while LNCaP‐LN3, a derivative of LNCaP, expresses high levels of wild‐type plexinB1 only. Sema4D stimulation increases the motility and anchorage independent growth of both cell lines, showing that these responses are not dependent on the presence of the Thr1697Ala form of plexinB1. ErbB2 and plexinB1 are expressed in primary prostate epithelial cells.

CONCLUSIONS

PlexinB1 signals via ErbB2 to increase the invasive phenotype of prostate cancer cells. Both wild‐type and mutant forms of plexinB1 are potential targets for anti‐cancer therapy in prostate tumors that express ErbB2. Prostate 73:1326–1335, 2013. © 2013 The Authors. The Prostate published by Wiley Periodicals, Inc.     

Transactivation of epidermal growth factor receptor after heparin-binding epidermal growth factor-like growth factor shedding in the migration of prostate cancer cells promoted by bombesin

BACKGROUND: A pathway consisting of bombesin, G-protein coupling receptors (GPCRs), metalloproteases, pro-heparin-binding epidermal growth factor (proHB-EGF), and epidermal growth factor receptor (EGFR) has been reported in prostate cancer cells. The occurrence of HB-EGF shedding from proHB-EGF in this pathway, however, has not been proven directly. In addition, it is still unclear how much this pathway contributes to the migration of prostate cancer cells. In this study, we tried to directly elucidate HB-EGF shedding in this pathway and to determine its contribution to the migration of prostate cancer cells. METHODS: RT-PCR and indirect immunofluorescence staining for HB-EGF and its receptors, such as EGFR and HER4/erbB4, were performed on PC-3 cells. The influences of bombesin, anti-EGFR neutralizing monoclonal antibody, HB-EGF, and HB-EGF shedding inhibitor on the migration of PC-3 cells were studied by means of in vitro wound assays. The amount of HB-EGF shed from PC-3 cells with alkaline phosphatase-tagged HB-EGF in the presence of bombesin was determined by measuring AP activity. Immunoprecipitations and phosphotyrosine Western blotting were performed to detect EGFR transactivated by bombesin. RESULTS: PC-3 expressed HB-EGF and EGFR, but not HER4/erbB4. PC-3 migrated in the presence of bombesin, but its migration was partly inhibited by the neutralizing antibody against EGFR. PC-3 also migrated in the presence of HB-EGF, but HB-EGF shedding inhibitor partly inhibited this phenomenon. HB-EGF was shed from PC-3 cells in the presence of bombesin, and this shedding was inhibited by HB-EGF shedding inhibitor. In addition, the EGFR on PC-3 was activated in the presence of bombesin and inactivated in the presence of HB-EGF shedding inhibitor. CONCLUSIONS: These results indicated that HB-EGF shedding and the following transactivation of EGFR occurs in this pathway and that this pathway partly contributes to the migration of prostate cancer cells.     

Involvement of HGF/SF-Met signaling in prostate adenocarcinoma cells: evidence for alternative mechanisms leading to a metastatic phenotype in Pr-14c

BACKGROUND: Hepatocyte growth factor/scatter factor (HGF/SF) facilitates intercellular communication between the epithelial carcinoma and its surrounding stromal tissue during metastatic invasion through interaction with its proto-oncogenic receptor, Met, found on carcinoma cells. This study utilizes the C31/Tag transgenic mouse prostate cancer cell line model in an attempt to characterize the interaction between HGF/SF and Met on the metastatic potential of prostate cancer. METHODS: Exogenous HGF was supplied to the prostate adenocarcinoma cell line (Pr-14) and metastatic cell line (Pr-14c) to evaluate mitogenicity by proliferation assays, morphological characteristics on an extracellular matrix substrate, and motogenic properties using the scatter assay, invasion chambers, and zymogram studies to analyze secretory enzymes produced by the cell lines. RESULTS: RNA and protein analyses show that the cell lines express similar amounts of Met. Pr-14 cells have an increased growth rate following HGF/SF treatment, whereas the metastatic Pr-14c cells show little change. Morphological studies of Pr-14c cells on extracellular matrix demonstrate negligible changes when compared to the tubular formation of Pr-14 cells after HGF/SF stimulation. Motility studies of the metastatic cells following HGF/SF treatment reveal a potentially faulty signaling pathway downstream of Met activation in the metastatic prostate cells. CONCLUSIONS: Our studies suggest that proliferation, invasion, and cell morphological characteristics may be induced independently from the HGF/SF-Met pathway in C31/Tag metastatic prostate cancer cells.     

沉默前列腺特异性膜抗原促进前列腺癌LNCAP细胞上皮-间质转化及迁移、侵袭的研究

目的 利用RNAi技术沉默LNCAP细胞中前列腺特异性膜抗原（PSMA）表达并检测表达情况,检测沉默PSMA后LNCAP细胞迁移及侵袭等生物学行为的变化情况,以及LNCAP细胞中上皮-间质转化标志蛋白的变化情况。方法 培养LNCAP细胞,分为si-PSMA组,阴性对照（negative control siRNA）组,抑制剂LY294002组和LY294002+si-PSMA组,采用qRT-PCR和Western blot技术检测沉默PSMA后LNCAP细胞中PSMA的mRNA和蛋白表达情况,通过Transwell小室穿透实验检测LNCAP细胞迁移及侵袭能力改变,通过Western blot蛋白印迹法检测E-cadherin、β-cadherin、vimentin,snail等细胞上皮-间质转化标志蛋白的表达情况以及p-Akt(ser473)蛋白表达情况。结果 与阴性对照组相比,si-PSMA组PSMA的mRNA和蛋白表达水平都明显降低（P<0.05）,Transwell结果显示迁移及侵袭细胞增多（P<0.01）,LY294002组细胞迁移及侵袭下调（P<0.05）,...     

Inhibition of cortactin and SIRT1 expression attenuates migration and invasion of prostate cancer DU145 cells

Objectives: Cortactin is overexpressed in various types of cancer and enhances cell motility. It has been recently reported that silent mating type information regulation 2 homolog 1 interacts with cortactin and promotes cell migration. Here, we examined the role of cortactin and silent mating type information regulation 2 homolog 1 in migration and invasion of prostate cancer cells. Methods: The cortactin expression levels in DU145, LNCaP and PC3 prostate cancer cells, and in PrEC normal human prostate epithelial cells were evaluated by western blot analysis. In DU145 cells, the expression of cortactin or silent mating type information regulation 2 homolog 1 was inhibited by small interfering RNA, and the effects of their knockdown on migration and invasion were examined by cell migration and invasion assays. To determine the localization of cortactin and silent mating type information regulation 2 homolog 1, western blot and immunofluorescence microscopic analyses were carried out. The functional interaction between silent mating type information regulation 2 homolog 1 and cortactin was also studied by in vivo acetylation assay. Results: The protein expression of cortactin was significantly higher in DU145 cells than in other cell lines. Knockdown of cortactin or silent mating type information regulation 2 homolog 1 expression inhibited both migration and invasion of DU145 cells. Similarly to cortactin, silent mating type information regulation 2 homolog 1 was found to be predominantly expressed in the cytoplasm. Finally, the knockdown of silent mating type information regulation 2 homolog 1 expression increased the acetylation level of cortactin. Conclusions: Our findings suggest that inhibition of cortactin or silent mating type information regulation 2 homolog 1 expression attenuates migration and invasion of DU145 cells and this could represent a promising strategy to regulate metastasis of prostate cancer.