Shiqi Li

MicroRNA-124-3p inhibits cell migration and invasion in bladder cancer cells by targeting ROCK1

BackgroundIncreasing evidence has suggested that dysregulation of certain microRNAs (miRNAs) may contribute to human disease including carcinogenesis and tumor metastasis in human. miR-124-3p is down-regulated in various cancers, and modulates proliferation and aggressiveness of cancer cells. However, the roles of miR-124-3p in human bladder cancer are elusive. Thus, this study was conducted to investigate the biological functions and its molecular mechanisms of miR-124-3p in human bladder cancer cell lines, discussing whether it has a potential to be a therapeutic biomarker of bladder cancer.MethodsThree human bladder cancer cell lines and samples from ten patients with bladder cancer were analyzed for the expression of miR-124-3p by quantitative RT--PCR. Exogenetic overexpression of miR-124-3p was established by transfecting mimics into T24, UM-UC-3 and J82 cells, after that cell proliferation and cell cycle were assessed by MTT assay, flow cytometry and Colony-forming assay. Cell motility and invasion ability were evaluated by wound healing assay and transwell assay. Tissue microarray, and immunohistochemistry with antibodies against ROCK1, MMP2 and MMP9 was performed using the peroxidase and DAB methods. The target gene of miR-124-3p was determined by luciferase assays, quantitative RT--PCR and western blot. The regulation of epithelial-to-mesenchymal transition by miR-124-3p was analyzed by western blot.ResultsmiR-124-3p is frequently down-regulated in bladder cancer both in three bladder cancer cell lines, T24, UM-UC-3, J82 and clinical samples. Overexpression of miR-124-3p induced G1-phase arrest in T24, UM-UC-3 and J82 cell lines and suppressed cell growth in colony-forming assay. miR-124-3p significantly repressed the capability of migration and invasion of bladder cancer cells. In addition, ROCK1 was identified as a new target of miR-124-3p. ROCK1, MMP2, MMP9 were up-regulated in bladder cancer tissues. Furthermore, we demonstrated miR-124-3p could inhibit bladder cancer cell epithelial mesenchymal transfer, and regulated the expression of c-Met, MMP2, MMP9.ConclusionsmiR-124-3p can repress the migration and invasion of bladder cancer cells via regulating ROCK1. Our data indicate that miR-124-3p could be a tumor suppressor and may have a potential to be a diagnostics or predictive biomarker in bladder cancer.

MicroRNA-409-3p Inhibits Migration and Invasion of Bladder Cancer Cells via Targeting c-Met

There is increasing evidence suggesting that dysregulation of certain microRNAs (miRNAs) may contribute to tumor progression and metastasis. Previous studies have shown that miR-409-3p is dysregulated in some malignancies, but its role in bladder cancer is still unknown. Here, we find that miR-409-3p is down-regulated in human bladder cancer tissues and cell lines. Enforced expression of miR-409-3p in bladder cancer cells significantly reduced their migration and invasion without affecting cell viability. Bioinformatics analysis identified the pro-metastatic gene c-Met as a potential miR-409-3p target. Further studies indicated that miR-409-3p suppressed the expression of c-Met by binding to its 3′-untranslated region. Silencing of c-Met by small interfering RNAs phenocopied the effects of miR-409-3p overexpression, whereas restoration of c-Met in bladder cancer cells bladder cancer cells overexpressing miR-409-3p, partially reversed the suppressive effects of miR-409-3p. We further showed that MMP2 and MMP9 may be downstream effector proteins of miR-409-3p. These findings indicate that miR-409-3p could be a potential tumor suppressor in bladder cancer.

MicroRNA-490-5p inhibits proliferation of bladder cancer by targeting c-Fos.

MicroRNAs (miRNAs) are non-protein-coding sequences that play a crucial role in tumorigenesis by negatively regulating gene expression. Here, we found that miR-490-5p is down-regulated in human bladder cancer tissue and cell lines compared to normal adjacent tissue and a non-malignant cell line. To better characterize the function of miR-490-5p in bladder cancer, we over-expressed miR-490-5p in bladder cancer cell lines with chemically synthesized mimics. Enforced expression of miR-490-5p in bladder cancer cells significantly inhibited the cell proliferation via G1-phase arrest. Further studies found the decreased c-Fos expression at both mRNA and protein levels and Luciferase reporter assays demonstrated that c-Fos is a direct target of miR-490-5p in bladder cancer. These findings indicate miR-490-5p to be a novel tumor suppressor of bladder cancer cell proliferation through targeting c-Fos.

miR-26a inhibits proliferation and motility in bladder cancer by targeting HMGA1.

It is increasingly clear that microRNAs play a crucial role in tumorigenesis. Recently, emerging evidence suggested that miR‐26a is aberrantly expressed in tumor tissues. In our study, frequent down‐regulation of miR‐26a was observed in 10 human bladder cancer tissues. Forced expression of miR‐26a in the bladder cancer cell line T24 inhibited cell proliferation and impaired cell motility. High mobility group AT‐hook 1 (HMGA1), a gene that modulates cell cycle transition and cell motility, was verified as a novel target of miR‐26a in bladder cancer. These findings indicate an important role for miR‐26a in the molecular etiology of bladder cancer and implicate the potential application of miR‐26a in bladder cancer therapy.

Downregulation of microRNA-182-5p contributes to renal cell carcinoma proliferation via activating the AKT/FOXO3a signaling pathway

BackgroundEmerging evidence has suggested that dysregulation of miR-182-5p may contribute to tumor development and progression in several types of human cancers. However, its role in renal cell carcinoma (RCC) is still unknown.MethodsQuantitative RT-PCR was used to quantify miR-182-5p expression in RCC clinical tissues. Bisulfite sequencing PCR was used for DNA methylation analysis. The CCK-8, colony formation, flow cytometry, and a xenograft model were performed. Immunohistochemistry was conducted using the peroxidase and DAB methods. A miR-182-5p target was determined by luciferase reporter assays, quantitative RT-PCR, and Western blotting.ResultsmiR-182-5p is frequently down-regulated in human RCC tissues. Epigenetic modulation may be involved in the regulation of miR-182-5p expression. Enforced expression of miR-182-5p in RCC cells significantly inhibited the proliferation and tumorigenicity in vitro and in vivo. Additionally, overexpression of miR-182-5p induced G1-phase arrest via inhibition of AKT/FOXO3a signaling. Moreover, FLOT1 was confirmed as a target of miR-182-5p. Silencing FLOT1 by small interfering RNAs phenocopied the effects of miR-182-5p overexpression, whereas restoration of FLOT1 in miR-182-5p -overexpressed RCC cells partly reversed the suppressive effects of miR-182-5p.ConclusionsThese findings highlight an important role for miR-182-5p in the pathogenesis of RCC, and restoration of miR-182-5p could be considered as a potential therapeutic strategy for RCC therapy.

c-Met and CREB1 are involved in miR-433-mediated inhibition of the epithelial-mesenchymal transition in bladder cancer by regulating Akt/GSK-3β/Snail signaling.

Emerging evidence has suggested that microRNAs (miRNAs) have an important role in tumor development and progression by regulating diverse cellular pathways. Here we describe the function and regulation network of miR-433 in bladder cancer (BCa). miR-433 is frequently downregulated in BCa tissues compared with adjacent non-cancerous tissues. Epigenetic mechanisms may be involved in the regulation of miR-433 expression. Enforced expression of miR-433 significantly inhibits proliferation, colony formation, migration, and invasion in BCa cells. In addition, miR-433 inhibits the epithelial–mesenchymal transition (EMT) in BCa cells by regulating c-Met/Akt/GSK-3β/Snail signaling pathway. Both c-Met and CREB1 are downstream target genes of miR-433. CREB1 can also indirectly regulate c-Met/Akt/GSK-3β/Snail signaling via MITF. Furthermore, CREB1 expression is an independent prognostic factor for overall survival in patients with BCa. Finally, there appears to exist a reciprocal regulation between c-Met and miR-433/miR-409-3p. Taken together, this study reveals that miR-433-c-MET/CREB1-Akt/GSK-3β/Snail signaling is critical to EMT in BCa. Targeting the pathway described here may open up new prospects to restrict metastatic progression of BCa.

A meta-analysis including dose-response relationship between night shift work and the risk of colorectal cancer

A meta-analysis was conducted to quantitatively evaluate the correlation between night shift work and the risk of colorectal cancer. We searched for publications up to March 2015 using PubMed, Web of Science, Cochrane Library, EMBASE and the Chinese National Knowledge Infrastructure databases, and the references of the retrieved articles and relevant reviews were also checked. OR and 95% CI were used to assess the degree of the correlation between night shift work and risk of colorectal cancer via fixed- or random-effect models. A dose-response meta-analysis was performed as well. The pooled OR estimates of the included studies illustrated that night shift work was correlated with an increased risk of colorectal cancer (OR = 1.318, 95% CI 1.121–1.551). No evidence of publication bias was detected. In the dose-response analysis, the rate of colorectal cancer increased by 11% for every 5 years increased in night shift work (OR = 1.11, 95% CI 1.03–1.20). In conclusion, this meta-analysis indicated that night shift work was associated with an increased risk of colorectal cancer. Further researches should be conducted to confirm our findings and clarify the potential biological mechanisms.

MicroRNA-320c inhibits tumorous behaviors of bladder cancer by targeting Cyclin-dependent kinase 6

BackgroundIncreasing evidence has suggested that dysregulation of microRNAs (miRNAs) could contribute to human disease including cancer. Previous miRNA microarray analysis illustrated that miR-320c is down-regulated in various cancers. However, the roles of miR-320c in human bladder cancer have not been well elucidated. Therefore, this study was performed to investigate the biological functions and molecular mechanisms of miR-320c in human bladder cancer cell lines, discussing whether it could be a therapeutic biomarker of bladder cancer in the future.MethodsTwo human bladder cancer cell lines and samples from thirteen patients with bladder cancer were analyzed for the expression of miR-320c by quantitative RT-PCR. Over-expression of miR-320c was established by transfecting mimics into T24 and UM-UC-3. Cell proliferation and cell cycle were assessed by cell viability assay, flow cytometry and colony formation assay. Cell motility ability was evaluated by transwell assay. The target gene of miR-320c was determined by luciferase assay, quantitative RT-PCR and western blot. The regulation of cell cycle and mobility by miR-320c was analyzed by western blot.ResultsWe observed that miR-320c was down-regulated in human bladder cancer tissues and bladder cancer cell lines T24 and UM-UC-3. Over-expression of miR-320c could induce G1 phase arrest in UM-UC-3 and T24 cells, and subsequently inhibited cell growth. We also indentified miR-320c could impair UM-UC-3 and T24 cell motility. In addition, we identified CDK6, a cell cycle regulator, as a novel target of miR-320c. Moreover, we demonstrated miR-320c could induce bladder cancer cell cycle arrest and mobility via regulating CDK6. We also observed that inhibition of miR-320c or restoration of CDK6 in miR-320c-over-expressed bladder cancer cells partly reversed the suppressive effects of miR-320c.ConclusionsmiR-320c could inhibit the proliferation, migration and invasion of bladder cancer cells via regulating CDK6. Our study revealed that miR-320c could be a therapeutic biomarker of bladder cancer in the future.

MicroRNA-195-5p, a new regulator of Fra-1, suppresses the migration and invasion of prostate cancer cells

BackgroundAn increasing number of studies have demonstrated that deregulation of microRNAs (miRNAs) was a common event in tumor tissues and miRNAs would be treated as ideal tumor biomarkers or therapeutic targets. miR-195-5p (termed as miR-195 for briefly in the following part) was suggested to function as a tumor suppressor in cancer development and progression. However, the roles of miR-195 in human prostate cancer are still elusive. Thus, this study was performed to investigate the biological functions and its molecular mechanisms of miR-195 in human prostate cancer cell lines, discussing whether it has a potential to be a therapeutic way of prostate cancer.MethodsTwo human prostate cancer cell lines were analyzed for the expression of miR-195 by quantitative real-time reverse transcription–polymerase chain reaction (RT–PCR). A gain-of-function study of miR-195 was conducted by transfecting mimics into DU145 and PC3 cells and cell motility and invasion ability were evaluated by wound healing assay and transwell assay. Tissue microarray, and immunohistochemistry with antibodies against Fra-1 was performed using the peroxidase and DAB methods. The target gene of miR-195 was determined by luciferase assay, quantitative RT–PCR and western blot. The regulation of motility by miR-195 was analyzed by western blot.ResultsmiR-195 was frequently down-regulated in both prostate cancer cell lines, DU145 and PC3. Overexpression of miR-195 significantly repressed the capability of migration and invasion of prostate cancer cells. In addition, we identified Fra-1, a cell motility regulator, as a novel target of miR-195. Fra-1 was up-regulated in prostate cancer tissues. We also observed that inhibition of miR-195 or restoration of Fra-1 in miR-195-over-expressed prostate cancer cells partially reversed the suppressive effects of miR-195. Furthermore, we demonstrated miR-195 could inhibit prostate cancer cell motility by regulated the expression of c-Met, MMP1, MMP9.ConclusionsmiR-195 can repress the migration and invasion of prostate cancer cells via regulating Fra-1. Our results indicate that miR-195 could be a tumor suppressor and may have a potential to be a diagnostics or therapeutic target in prostate cancer.

Meta-analysis of nonsteroidal anti-inflammatory drug intake and prostate cancer risk

BackgroundEpidemiological studies of the association between nonsteroidal anti-inflammatory drug (NSAID) intake and the risk of prostate cancer still remain controversial. Therefore, we conducted a meta-analysis to evaluate the potential association between NSAID intake and prostate cancer risk.MethodsEligible studies were retrieved by both computerized searches and reviews of references. Subgroup analyses on country and design of study were also performed. Random or fixed-effect models were used to pool estimates of odds ratios (ORs) with 95% confidence intervals (CIs).ResultsWe observed that the intake of aspirin was associated with a marginally decreased risk of prostate cancer (OR =0.95, 95% CI =0.93 to 0.98). A similar result was found between nonaspirin NSAIDs and prostate cancer risk (OR =0.94, 95% CI =0.90 to 0.98). However, a positive relation between all-NSAID intake and prostate cancer risk was observed (OR =1.18, 95% CI =1.15 to 1.22).ConclusionsWe observed a marginally inverse correlation between the intake of aspirin and prostate cancer risk. On the contrary, a positive relationship between all-NSAID intake and prostate cancer was detected. Further research needs to be conducted to better clarify potential biological mechanisms.