miR-145靶向调控DAB2对前列腺癌PC3细胞迁移和侵袭能力的影响

已有研究表明, miR-145在多种肿瘤中低表达, 并与细胞增殖和转移相关。文章通过生物信息学分析并结合体外实验鉴定, 发现DAB2(Disabled homolog 2)为miR-145在肿瘤转移过程中累及的新靶点。DAB2一直被认为是一个重要的抑癌基因, 在多种肿瘤标本中表达低下。然而, 研究发现, 在具高侵袭能力的前列腺癌细胞株PC3中DAB2基因却呈较高水平表达。另外, 外源表达miR-145能显著下调 DAB2表达水平, 并抑制PC3细胞的迁移和侵袭能力, 且这种miR-145诱导的PC3细胞功能缺陷能被DAB2过表达修复。上述结果表明, miR-145能通过靶向调控DAB2而影响高侵袭前列腺癌细胞的迁移和侵袭能力。     

SIK1作为miR-93新的靶基因抑制前列腺癌细胞增殖、侵袭和迁移

该文探讨了SIK1作为miR-93新的靶基因对前列腺癌细胞增殖、侵袭和迁移的抑制作用。采用重组质粒pcDNA3.1-SIK1上调前列腺癌细胞中SIK1的表达后,利用CCK8和克隆形成实验检测细胞增殖;利用细胞划痕和Transwell实验检测细胞侵袭和迁移;利用Western blot检测E-cadherin和Vimentin的蛋白表达。采用生物信息学方法预测靶向SIK1 mRNA的3’UTR的miRNAs并进行筛选;双荧光素酶报告实验和Western blot验证miR-93靶向调控SIK1。结果显示,上调SIK1的表达能抑制前列腺癌细胞的增殖、侵袭和迁移,并增加E-cadherin和减少Vimentin蛋白表达;miR-93能够靶向负调控SIK1。总之,SIK1可作为miR-93一个新的靶基因抑制前列腺癌细胞增殖、侵袭和迁移。     

miR-888 is an expressed prostatic secretions-derived microRNA that promotes prostate cell growth and migration

microRNAs (miRNAs) are a growing class of small non-coding RNAs that exhibit widespread dysregulation in prostate cancer. We profiled miRNA expression in syngeneic human prostate cancer cell lines that differed in their metastatic potential in order to determine their role in aggressive prostate cancer. miR-888 was the most differentially expressed miRNA observed in human metastatic PC3-ML cells relative to non-invasive PC3-N cells, and its levels were higher in primary prostate tumors from cancer patients, particularly those with seminal vesicle invasion. We also examined a novel miRNA-based biomarker source called expressed prostatic secretions in urine (EPS urine) for miR-888 expression and found that its levels were preferentially elevated in prostate cancer patients with high-grade disease. These expression studies indicated a correlation for miR-888 in disease progression. We next tested how miR-888 regulated cancer-related pathways in vitro using human prostate cancer cell lines. Overexpression of miR-888 increased proliferation and migration, and conversely inhibition of miR-888 activity blocked these processes. miR-888 also increased colony formation in PC3-N and LNCaP cells, supporting an oncogenic role for this miRNA in the prostate. Our data indicates that miR-888 functions to promote prostate cancer progression and can suppress protein levels of the tumor suppressor genes RBL1 and SMAD4. This miRNA holds promise as a diagnostic tool using an innovative prostatic fluid source as well as a therapeutic target for aggressive prostate cancer.     

Distinct roles of AKT isoforms in regulating β1-integrin activity, migration, and invasion in prostate cancer

AKT1 and AKT2 kinases have been shown to play opposite roles in breast cancer migration and invasion. In this study, an RNA interference screen for integrin activity inhibitors identified AKT1 as an inhibitor of β1-integrin activity in prostate cancer. Validation experiments investigating all three AKT isoforms demonstrated that, unlike in breast cancer, both AKT1 and AKT2 function as negative regulators of cell migration and invasion in PC3 prostate cancer cells. Down-regulation of AKT1 and AKT2, but not AKT3, induced activation of cell surface β1-integrins and enhanced adhesion, migration, and invasion. Silencing of AKT1 and AKT2 also resulted in increased focal adhesion size. Importantly, the mechanisms involved in integrin activity regulation were distinct for the two AKT isoforms. Silencing of AKT1 relieved feedback suppression of the expression and activity of several receptor tyrosine kinases, including EGFR and MET, with established cross-talk with β1-integrins. Silencing of AKT2, on the other hand, induced up-regulation of the microRNA-200 (miR-200) family, and overexpression of miR-200 was sufficient to induce integrin activity and cell migration in PC3 cells. Taken together, these data define an inhibitory role for both AKT1 and AKT2 in prostate cancer migration and invasion and highlight the cell type-specific actions of AKT kinases in the regulation of cell motility.     

miR-19a-3p在前列腺癌细胞侵袭和迁移中的作用

miR-19a-3p通过多种机制调节癌细胞的增殖和转移,然而,miR-19a-3p在前列腺癌转移中的生物学作用和机制尚不清楚。本研究旨在考察mir-19a-3p在前列腺癌中的表达情况,及其对细胞侵袭和迁移的影响。本研究发现,miR-19a-3p在骨转移性前列腺癌组织和前列腺癌细胞中明显下调。上调miR-19a-3p可显著抑制前列腺癌细胞的侵袭和迁移。然而,下调miR-19a-3p则会逆转上述变化。此外,本研究还发现miR-19a-3p通过靶向TGF-β信号传导的下游效应物SMAD2来抑制前列腺癌细胞中TGF-β信号传导的活性,从而抑制前列腺癌细胞的侵袭和迁移。因此,本研究表明mir-19a-3p与前列腺癌的发生发展密切相关,mir-19a-3p有望成为前列腺癌的新治疗靶点及生物标志物。     

MicroRNA-4723 Inhibits Prostate Cancer Growth through Inactivation of the Abelson Family of Nonreceptor Protein Tyrosine Kinases

The Abelson (c-Abl) proto-oncogene encodes a highly conserved nonreceptor protein tyrosine kinase that plays a role in cell proliferation, differentiation, apoptosis and cell adhesion. c-Abl represents a specific anti-cancer target in prostate cancer as aberrant activity of this kinase has been implicated in the stimulation of prostate cancer growth and progression. However, the mechanism of regulation of c-Abl is not known. Here we report that Abl kinases are regulated by a novel microRNA, miR-4723, in prostate cancer. Expression profiling of miR-4723 expression in a cohort of prostate cancer clinical specimens showed that miR-4723 expression is widely attenuated in prostate cancer. Low miR-4723 expression was significantly correlated with poor survival outcome and our analyses suggest that miR-4723 has significant potential as a disease biomarker for diagnosis and prognosis in prostate cancer. To evaluate the functional significance of decreased miR-4723 expression in prostate cancer, miR-4723 was overexpressed in prostate cancer cell lines followed by functional assays. miR-4723 overexpression led to significant decreases in cell growth, clonability, invasion and migration. Importantly, miR-4723 expression led to dramatic induction of apoptosis in prostate cancer cell lines suggesting that miR-4723 is a pro-apoptotic miRNA regulating prostate carcinogenesis. Analysis of putative miR-4723 targets showed that miR-4723 targets integrin alpha 3 and Methyl CpG binding protein in addition to Abl1 and Abl2 kinases. Further, we found that the expression of Abl kinase is inversely correlated with miR-4723 expression in prostate cancer clinical specimens. Also, Abl1 knockdown partially phenocopies miR-4723 reexpression in prostate cancer cells suggesting that Abl is a functionally relevant target of miR-4723 in prostate cancer. In conclusion, we have identified a novel microRNA that mediates regulation of Abl kinases in prostate cancer. This study suggests that miR-4723 may be an attractive target for therapeutic intervention in prostate cancer.     

Genistein Suppresses Prostate Cancer Growth through Inhibition of Oncogenic MicroRNA-151

Genistein has been shown to suppress the growth of several cancers through modulation of various pathways. However, the effects of genistein on the regulation of oncogenic microRNA-151 (miR-151) have not been reported. In this study, we investigated whether genistein could alter the expression of oncogenic miR-151 and its target genes that are involved in the progression and metastasis of prostate cancer (PCa). Real-time RT-PCR showed that the expression of miR-151 was higher in PC3 and DU145 cells compared with RWPE-1 cells. Treatment of PC3 and DU145 cells with 25 μM genistein down-regulated the expression of miR-151 compared with vehicle control. Inhibition of miR-151 in PCa cells by genistein significantly inhibited cell migration and invasion. In-silico analysis showed that several genes (CASZ1, IL1RAPL1, SOX17, N4BP1 and ARHGDIA) suggested to have tumor suppressive functions were target genes of miR-151. Luciferase reporter assays indicated that miR-151 directly binds to specific sites on the 3'UTR of target genes. Quantitative real-time PCR analysis showed that the mRNA expression levels of the five target genes in PC3 and DU145 were markedly changed with miR-151 mimics and inhibitor. Kaplan-Meier curves and log-rank tests revealed that high expression levels of miR-151 had an adverse effect on survival rate. This study suggests that genistein mediated suppression of oncogenic miRNAs can be an important dietary therapeutic strategy for the treatment of PCa.     

miR-375 Mediated Acquired Chemo-Resistance in Cervical Cancer by Facilitating EMT

Acquired chemo-resistance is one of the key causal factors in cancer death. Emerging evidences suggest that miRNA and epithelial–mesenchymal transition play critical roles in the chemo-resistance in cancers. Here, we showed the association of paclitaxel-resistance with miR-375 over-expression and epithelial–mesenchymal transition inducement in cervical cancer. Using different cervical cancer cell models, we found that paclitaxel transiently induced up-regulation of miR-375 expression, proliferation inhibition, transition from epithelial to mesenchymal phenotype, and consequently impaired paclitaxel sensitivity. Forced over-expression of miR-375 may suppress Ecadherin expression by a directly targeting pathway, which led to paclitaxel resistance. Contrarily, re-expression of Ecadherin partly reversed epithelial–mesenchymal transition phenotype and miR-375 induced paclitaxel-resistance. Our findings suggest that paclitaxel-induced miR-375 over-expression facilitates epithelial–mesenchymal transition process via directly targeting Ecadherin, proliferation inhibition, and consequently results in chemo-resistance in cervical cancer cells. A reversion of miR-375 or Ecadherin expression may be a novel therapeutic approach for overcoming chemo-resistance in cervical cancer.     

miR-105 Inhibits Prostate Tumour Growth by Suppressing CDK6 Levels

A significant role for micro (mi)RNA in the regulation of gene expression in tumours has been recently established. In order to further understand how miRNA expression may contribute to prostate tumour growth and progression, we evaluated expression of miRNA in two invasive prostate tumour lines, PC3 and DU145, and compared it to that in normal prostate epithelial cells. Although a number of miRNAs were differentially expressed, we focused our analysis on miR-105, a novel miRNA not previously linked to prostate cancer. miR-105 levels were significantly decreased in both tumour cell lines in comparison to normal prostate epithelial cells. To determine its potential role in prostate cancer pathogenesis, we overexpressed miR-105 in both PC3 and DU145 cells and determined its effect on various tumourigenic properties. miR-105 overexpression inhibited tumour cell proliferation, tumour growth in anchorage-independent three-dimensional conditions and tumour invasion in vitro, properties of highly aggressive tumour cells. Of potential clinical significance, miR-105 overexpression inhibited tumour growth in vivo in xenograft models using these cell lines. We further identified CDK6 as a putative target of miR-105 which is likely a main contributor to the inhibition of tumour cell growth observed in our assays. Our results suggest that miR-105 inhibits tumour cell proliferation and hence may represent a novel therapeutically relevant cellular target to inhibit tumour growth or a marker of aggressive tumours in prostate cancer patients.     

miR-125b在前列腺癌1E8细胞运动转移中的作用及其分子机制的初步探讨

目的 研究 miR-125b在前列腺癌高低转移潜能细胞中的表达差异及其对高转移细胞株1E8细胞的运动转移中的作用和可能的分子机制.方法 realtime PCR法检测前列腺癌高低转移潜能配对细胞系中 miR-125b的表达差异.通过划痕实验及transwell实验观察1E8细胞及转染 miR-125b 抑制剂及其阴性对照后该细胞运动转移能力的变化.结果 realtime PCR结果显示高转移潜能1E8细胞中miR-125b表达水明显高于低转移潜能2B4细胞;下调miR-125b会减弱1E8细胞的运动转移能力.结论 miR-125b可促进前列腺癌细胞的运动转移能力.     

miR-613 inhibits cell migration and invasion by downregulating Daam1 in triple-negative breast cancer

Dishevelled-associated activator of morphogenesis 1 (Daam1) is a formin protein and participates in regulating cell migration of triple-negative breast cancer (TNBC) cells. The specific miRNA targeting Daam1 and mediating cell migration and invasion remains obscure. This experiment investigated the suppressive role of miR-613 in TNBC cells. The luciferase activity of Daam1 3′-untranslated region (3′-UTR) based reporters constructed in HEK-293T and MCF-7 cells suggested that Daam1 was the target gene of miR-613. Overexpressed miR-613 reduced the protein level of Daam1, weakened RhoA activity, and retarded the cell migration, cell invasion and colony formation of TNBC cells. Overexpression of Daam1 or RhoA rescued cell migration and invasion in miR-613-overexpressed TNBC cells, but failed to reverse colony formation. MiR-613 was significantly downregulated in breast cancer tissues compared with that in adjacent normal tissues. This downregulation in TNBC tissues and lymphnode metastatic breast cancer tissues was more obvious than that in non-TNBC tissues and non-metastatic cancer tissues, respectively. MiR-613 weakens the resistance of TNBC cells against paclitaxel rather than adriamycin, cyclophosphamide, docetaxel, and kaempferol. Taken together, miR-613 is involved in cell migration and invasion of TNBC cells via targeting Daam1/RhoA signaling pathway.     

microRNA-148a-3p enhances the effects of sevoflurane on hepatocellular carcinoma cell progression via ROCK1 repression

BackgroundSevoflurane (SEVO) inactivates the aggressiveness of hepatocellular carcinoma (HCC) cells by mediating microRNAs (miRNAs). Hence, we delved into the functional role of miR-148a-3p mediated by SEVO in HCC.MethodsLiver cells (L02) and HCC cells (HCCLM3 and Huh7) were exposed to SEVO to detect cell viability in HCC. HCCLM3 and Huh7 cells were treated with restored miR-148a-3p or depleted Rho-associated protein kinase 1 (ROCK1) to elucidate their roles in HCC cells' biological characteristics. HCCLM3 and Huh7 cells were treated with SEVO, and/or vectors that changed miR-148a-3p or ROCK1 expression to identify their combined functions in HCC cell progression. Tumor xenograft in nude mice was performed to determine growth ability of tumor. The target relationship between miR-148a-3p and ROCK1 was verified.ResultsSEVO inhibited proliferation, invasion and migration and enhanced apoptosis of HCCLM3 and Huh7 cells. MiR-148a-3p up-regulation or ROCK1 down-regulation inhibited HCCLM3 and Huh7 cell progression. ROCK1 was determined to be target gene of miR-148a-3p. Down-regulating miR-148a-3p or overexpressing ROCK1 mitigated cell aggressiveness inhibition caused by SEVO.ConclusionOur study elucidates that microRNA-148a-3p enhances the effects of sevoflurane on inhibiting proliferation, invasion and migration and enhancing apoptosis of HCC cells through suppression of ROCK1.     

MiR-203 controls proliferation,migration and invasive potential of prostate cancer cell lines

Prostate cancers show a slow progression from a local lesion (primary tumor) to a metastatic and hormone-resistant phenotype. After an initial step of hyperplasia, in a high percentage of cases a neoplastic transformation event occurs that, less frequently, is followed by epithelial to mesenchymal transition and invasion of healthy tissues (usually bones). MicroRNA-203 (miR-203) is a tumor suppressor microRNA often silenced in different malignancies. Here, we show that miR-203 is downregulated in clinical primary prostatic tumors compared to normal prostate tissue, and in metastatic prostate cancer cell lines compared to normal epithelial prostatic cells. Overexpression of miR-203 in brain or bone metastatic prostate cell lines (DU145 and PC3) is sufficient to induce a mesenchymal to epithelial transition with inhibition of cell proliferation, migration and invasiveness. We have identified CKAP2, LASP1, BIRC5, WASF1, ASAP1 and RUNX2 as new miR-203 direct target mRNAs involved in these events. Therefore, miR-203 could be a potentially new prognostic marker and therapeutic target in metastatic prostate cancer.     

miR-335 Targets SIAH2 and Confers Sensitivity to Anti-Cancer Drugs by Increasing the Expression of HDAC3

We previously reported the role of histone deacetylase 3 (HDAC3) in response to anti-cancer drugs. The decreased expression of HDAC3 in anti-cancer drug-resistant cancer cell line is responsible for the resistance to anti-cancer drugs. In this study, we investigated molecular mechanisms associated with regulation of HDAC3 expression. MG132, an inhibitor of proteasomal degradation, induced the expression of HDAC3 in various anti-cancer drug-resistant cancer cell lines. Ubiquitination of HDAC3 was observed in various anti-cancer drug-resistant cancer cell lines. HDAC3 showed an interaction with SIAH2, an ubiquitin E3 ligase, that has increased expression in various anti-cancer drug-resistant cancer cell lines. miRNA array analysis showed the decreased expression of miR-335 in these cells. Targetscan analysis predicted the binding of miR-335 to the 3′-UTR of SIAH2. miR-335-mediated increased sensitivity to anti-cancer drugs was associated with its effect on HDAC3 and SIAH2 expression. miR-335 exerted apoptotic effects and inhibited ubiquitination of HDAC3 in anti-cancer drug-resistant cancer cell lines. miR-335 negatively regulated the invasion, migration, and growth rate of cancer cells. The mouse xenograft model showed that miR-335 negatively regulated the tumorigenic potential of cancer cells. The down-regulation of SIAH2 conferred sensitivity to anti-cancer drugs. The results of the study indicated that the miR-335/SIAH2/HDAC3 axis regulates the response to anti-cancer drugs.     

Inhibition of Proliferation and Induction of Autophagy by Atorvastatin in PC3 Prostate Cancer Cells Correlate with Downregulation of Bcl2 and Upregulation of miR-182 and p21

The epidemiologic association between statin use and decreased risk of advanced prostate cancer suggests that statins may inhibit prostate cancer development and/or progression. Studies were performed to determine the effects of a model statin, atorvastatin (ATO), on the proliferation and differentiation of prostate cancer cells, and to identify possible mechanisms of ATO action. ATO inhibited the in vitro proliferation of both LNCaP and PC3 human prostate cancer cells in a dose- and time-dependent fashion. The greater inhibitory activity of ATO in PC3 cells was associated with induction of autophagy in that cell line, as demonstrated by increased expression of LC3-II. miR-182 was consistently upregulated by ATO in PC3 cells, but not in LNCaP cells. ATO upregulation of miR-182 in PC3 cells was p53-independent and was reversed by geranylgeraniol. Transfection of miR-182 inhibitors decreased expression of miR-182 by >98% and attenuated the antiproliferative activity of ATO. miR-182 expression in PC3 cells was also increased in response to stress induced by serum withdrawal, suggesting that miR-182 upregulation can occur due to nutritional stress. Bcl2 and p21 were identified to be potential target genes of miR-182 in PC3 cells. Bcl2 was downregulated and p21 was upregulated in PC3 cells exposed to ATO. These data suggest that miR-182 may be a stress-responsive miRNA that mediates ATO action in prostate cancer cells.