Deyao Wu

A functional polymorphism in Pre-miR-146a gene is associated with prostate cancer risk and mature miR-146a expression in vivo.

A G > C polymorphism (rs2910164) which is located in the sequence of miR‐146a precursor, results in a change from a G:U pair to a C:U mismatch in its stem region. To explore whether rs2910164 plays any role in prostate cancer (CaP), we analyzed the association between miR‐146a polymorphism and risk of CaP and the expression of miR‐146a with different genotypes in CaP tissues in southern Chinese Han population.

microRNA-133 inhibits cell proliferation, migration and invasion in prostate cancer cells by targeting the epidermal growth factor receptor

It has been shown that regulation of EGFR expression in prostate cancer cells is mostly at the transcriptional level. microRNA-133 (miR-133) has long been recognized as a muscle-specific miRNA which may regulate myoblast differentiation and participate in many myogenic diseases. Recently, it has been reported that miR-133 is also involved in other tumors, such as bladder cancer, esophageal cancer and may regulate cell motility in these cancer cells. In the present study, we examined the expression and effects of miR-133 in two hormone-insensitive prostate cancer cell lines. The expression of miR-133a and miR-133b were analyzed by quantitative RT-PCR. After transfection of miR-133a and miR-133b, cell viability assay, luciferase assay, western blot analysis, cell migration and invasion assay were conducted in Du145 and PC3 cells. In this study, we showed that miR‑133a and miR-133b are expressed at the detection limit in two hormone-insensitive prostate cancer cell lines, PC3 and DU145. Ectopic expression of miR-133 inhibited cell proliferation, migration and invasion in these cells. We also provide the first evidence that miR-133 may target EGFR. Our study provided the first glimpse of the functional role of miR-133 in two hormone-independent prostate cancer cell lines. These results may add to our knowledge on the molecular basis of prostate cancer progression.

microRNA-21 modulates cell proliferation and sensitivity to doxorubicin in bladder cancer cells.

Transitional cell carcinomas (TCCs) of the urinary bladder are common malignancies with a high recurrence rate. Since microRNA-21 (miR-21) may contribute to tumorigenesis and chemoresistance in many cancer types, we aimed to investigate its efficacy in TCCs. The expression of miR-21 and its target PTEN was determined by real-time qRT-PCR and western blotting, respectively in tumor tissues as well as adjacent non-tumor mucosa. The effect of miR-21 on cell proliferation and chemosensitivity to doxorubicin were measured using the MTT method. Cell apoptosis induced by doxorubicin was investigated using flow cytometry in the T24 cell line. BCL-2, AKT and pAKT were detected by western blotting for analysis of potential mechanisms. miR-21 was significantly up-regulated in tumor tissues while PTEN was expressed in lower levels compared to non-tumor tissues. A negative correlation between expression of miR-21 and PTEN was established in vivo. Cell proliferation and chemoresistance to doxorubicin were promoted by overexpression of miR-21 in T24 cells. BCL-2 up-regulation could be achieved by miR-21 overexpression, which prevented T24 cells from apoptosis induced by doxorubicin. Furthermore, the miR-21 induced BCL-2 up-regulation could be cancelled by the PI3K inhibitor LY294002. These data verified the oncogenic role of miR-21 in TCCs and may usher in new therapeutic strategies in treating this disease.

MicroRNA-133 inhibits cell proliferation, migration and invasion by targeting epidermal growth factor receptor and its downstream effector proteins in bladder cancer

Abstract Objective. MicroRNA-133a (miR-133a) and microRNA-133b (miR-133b) are located on chromosome 18 in the same bicistronic unit. Recently, they have been commonly identified as being down-regulated in various human malignancies, such as bladder cancer, pancreatic ductal adenocarcinoma, oesophageal squamous cell carcinoma of the tongue, and hepatocellular and lung carcinomas. The present study examined the effects of miR-133a and miR-133b in bladder cancer T24 and EJ cells. Material and methods. After transfection of miR-133a and miR-133b, the expression of miR-133a/b was assessed, and a cell viability assay, cell migration assay, cell invasion assay, luciferase assay and Western blot were conducted in bladder cancer T24 and EJ cells. Results. Both miR-133a and miR-133b were found to inhibit cell proliferation, migration and invasion in T24 and EJ cells. The first evidence was provided that miR-133a and miR-133b may directly target the epidermal growth factor receptor in bladder cancer. Conclusions. This study provided the first glimpse of the functional role of miR-133 in bladder cancer T24 and EJ cells. The results may increase our knowledge on the molecular basis of progression and provide potential therapy for bladder cancer.

MicroRNA-143 inhibits cell migration and invasion by targeting matrix metalloproteinase 13 in prostate cancer.

MicroRN-143 (miR‑143) has been previously reported to be downregulated in specific types of cancer, including colorectal, bladder, oral squamous cell, pituitary, cervical, nasopharyngeal, lymphoma and prostate cancer. In the present study, the effects of miR-143 on prostate cancer cell migration and invasion were examined. Following transfection with miR-143, miR-143 expression, cell migration and invasion assays, luciferase assay and western blot analysis were conducted in prostate cancer cell lines. The results indicated that miR-143 inhibits cell migration and invasion in DU145 and PC-3 cells. In addition, to the best of our knowledge, miR-143 was reported for the first time to directly target matrix metalloproteinase 13 (MMP-13) in prostate cancer. The results of the present study demonstrated that miR-143 suppresses cell migration and invasion by targeting MMP-13 in prostate cancer cell lines. These results indicated that miR-143 may be suitable for the development of novel molecular markers and therapeutic approaches to inhibit metastasis in prostate cancer.

microRNA-125b inhibits cell migration and invasion by targeting matrix metallopeptidase 13 in bladder cancer.

The expression of microRNA-125b (miR-125b) has been investigated in many human cancers. It has been demonstrated to be downregulated in certain types of cancer, such as bladder cancer, thyroid anaplastic carcinomas, squamous cell carcinoma of the tongue, hepatocellular carcinoma, ovarian and breast cancer. In the present study, we examined the effects of miR-125b on bladder cancer cell migration and invasion. Following transfection of miR-125b, the expression of miR-125b was analyzed in T24 and EJ bladder cancer cells. Additionally, cell migration, cell invasion and luciferase assays, as well as western blot analysis were conducted in the bladder cancer cells. In this study, we demonstrated that miR-125b inhibited cell migration and invasion in T24 and EJ cells. We also provided the first evidence that miR-125b may directly target matrix metalloproteinase 13 (MMP13) in bladder cancer. Our study provided evidence that miR-125b suppresses cell migration and invasion by targeting MMP13 in bladder cancer cell lines. These results suggested that miR-125b could be used for the development of new molecular markers and therapeutic approaches to inhibit bladder cancer metastasis.

microRNA‑99a inhibiting cell proliferation, migration and invasion by targeting fibroblast growth factor receptor 3 in bladder cancer

The expression of microRNA-99a (miRNA-99a) has been investigated in a number of human cancers. It has been reported to be downregulated in several types of cancer, including ovarian carcinoma, squamous cell carcinoma of the tongue, squamous cell lung carcinoma, hepatocellular carcinoma, bladder cancer, prostate cancer and childhood adrenocortical tumors. In the present study, the effects of miRNA-99a on bladder cancer cell proliferation, migration and invasion were examined. Following transfection of miRNA-99a, cell viability, cell migration assay, cell invasion, western blot analysis and luciferase assays were conducted in bladder cancer cell lines. It was found that miRNA-99a inhibits cell proliferation, migration and invasion in T24 and EJ cells. Additionally, this study provided the first evidence that miRNA-99a is likely to directly target fibroblast growth factor receptor 3 in bladder cancer. The study provided evidence that miRNA-99a suppresses cell proliferation, migration and invasion by targeting growth factor receptor 3 in bladder cancer cell lines. These results indicated that it could be investigated as a target for therapeutic drugs designed to treat bladder cancer.

A novel XPF-357A>C polymorphism predicts risk and recurrence of bladder cancer

Xeroderma pigmentosum group F (XPF) has an essential role in the nucleotide excision repair pathway that removes a wide variety of DNA lesions. We hypothesized that genetic variants in XPF are associated with bladder cancer risk and recurrence. We selected three tagging single nucleotide polymorphisms (tagSNPs) from the HapMap database for the Chinese and genotyped them in a two-stage case–control study to evaluate the association and further examined the functionality of a novel polymorphism in the promoter. The two-stage analysis found that the rs744154 tagSNP in the XPF intron 1, which was linkage disequilibrium with the –357A>C polymorphism in the promoter region, was associated with a protective effect on bladder cancer risk. Electrophoretic mobility shift assay (EMSA) further revealed that the –357C allele decreased the binding ability of transcriptional factors to the XPF promoter. The vector construct containing the –357C allele had a lower luciferase expression than did the –357A allele. The –357C allele in the transcription factor-binding site was also associated with decreased expression levels of both XPF mRNA and protein in bladder cancer tissues. Furthermore, patients with the –357C allele had a shorter overall recurrence-free survival than did patients with the –357A allele. Our results suggest that the XPF promoter –357A>C polymorphism may regulate the expression of XPF and thereby contribute to susceptibility to and prognosis of bladder cancer. Further larger studies with different populations are warranted to confirm these findings.

microRNA-133b downregulation and inhibition of cell proliferation, migration and invasion by targeting matrix metallopeptidase‑9 in renal cell carcinoma

microRNA (miRNA)-133b has been revealed to be downregulated in head and neck/oral, bladder, human non-small cell lung, colorectal and esophageal squamous cell cancer. The present study examined the expression of miR-133b in renal cell carcinoma (RCC) cell lines and the effects of miRNA-133b on RCC cell proliferation, migration and invasion. Quantitative polymerase chain reaction was used to detect the expression of miR-133b in RCC cell lines. Following transfection of miR-133b, the expression of miR-133b was examined and a cell viability assay, cell migration assay, cell invasion assay, western blot analysis and luciferase assay were conducted in RCC cell lines. The present study revealed that miRNA‑133b was downregulated and inhibited cell proliferation, migration and invasion in 786-O and A498 cells. In addition, to the best of our knowledge, the present study provided the first evidence that miRNA-133b may directly target matrix metallopeptidase 9 (MMP-9) in RCC. The present study also provided evidence that miRNA-133b suppresses cell proliferation, migration and invasion by targeting MMP-9 in RCC cell lines. These results suggested that miRNA-133b may be used for the development of novel molecular markers and therapeutic approaches to inhibit the metastasis of RCC.

Downregulation of Dicer, a component of the microRNA machinery, in bladder cancer.

Dysregulation of microRNA metabolism has been observed in a variety of human cancers. In this study, we evaluated the expression of the enzymes of the machinery Dicer, Drosha and DGCR8, in transitional cell carcinomas (TCCs) of the urinary bladder. The expression of Dicer, Drosha and DGCR8 was analyzed using semi-quantitative RT-PCR in clinical specimens from normal bladder mucosa, TCCs and their normal adjacent tissues (NATs). Immunohistochemistry was performed to compare the expression of Dicer in normal, TCCs and NATs. Our study demonstrated that Dicer mRNA levels in TCCs were significantly lower compared to normal samples and NAT samples. The immunohistochemistry results revealed that Dicer protein levels in TCCs were significantly downregulated compared to normal bladder mucosa and NATs. Our data demonstrated that Dicer is significantly downregulated in TCCs compared to paired NAT samples and normal samples, suggesting that reduced expression of Dicer may play an important role in bladder cancer.