Retraction Notice to: circFMN2 Sponges miR-1238 to Promote the Expression of LIM-Homeobox Gene 2 in Prostate Cancer Cells.

[This retracts the article DOI: 10.1016/j.omtn.2020.05.008.].

Label-free detection of multiple genitourinary cancers from urine by surface-enhanced Raman spectroscopy.

Detecting cancers through testing biological fluids, namely, "liquid biopsy", is noninvasive and shows great promise in cancer diagnosis, surveillance and screening. Many metabolites that may reflect cancer specificity are concentrated in and excreted through urine. In this study, urine samples were collected from healthy subjects and patients with bladder or prostate cancer. By using surface-enhanced Raman spectroscopy (SERS) with silver nanoparticles, urine sample spectra from 500-1800 cm-1 were obtained. The spectra were classified by principal component analysis and linear discriminant analysis (PCA-LDA). The results showed that the classification accuracy of the model for healthy individuals, bladder cancer patients and prostate cancer patients was 91.9%, and the classification accuracy of the test set was 89%, which indicated that SERS combined with the PCA-LDA diagnostic algorithm could be used as a classification and diagnostic tool to detect and distinguish bladder cancer and prostate cancer through testing urine.

circFMN2 Sponges miR-1238 to Promote the Expression of LIM-Homeobox Gene 2 in Prostate Cancer Cells.

Circular RNAs (circRNAs) regulate gene expression in different malignancies. However, the molecular mechanisms that link circRNAs with the tumorigenesis of prostate cancer (PCa) are not well understood. In the present study, we attempted to provide a novel basis for targeted therapy for PCa from the aspect of circRNA-microRNA (miRNA)-mRNA interaction. We investigated the expression of circRNAs in 5 paired PCa tissues and adjacent non-tumor tissues by microarray analysis. We focused on hsa_circ_0005100, which is located on chromosome 1 and derived from FMN2, and thus we named it circFMN2. The qRT-PCR was used to detect circFMN2 and target miRNA expression in PCa tissues and cell lines. Biological functional experiments were performed to detect the effects of circFMN2 on the biological behavior of PCa cells in vivo and in vitro. Bioinformatic analysis was utilized to predict potential miRNA target sites on circFMN2. High expression of circFMN2 was associated with PCa progression. Function assays revealed that knockdown of circFMN2 significantly reduced PCa cell growth in vitro and in vivo. Finally, we found that circFMN2 acts as a competing endogenous RNA (ceRNA) for miR-1238 to regulate LIM-homeobox gene 2 (LHX2) expression. circFMN2 regulates the miR-1238/LHX2 axis to promote PCa progression.

MiR-378 suppresses prostate cancer cell growth through downregulation of MAPK1 in vitro and in vivo.

Prostate cancer is one of the biggest health problems for the aging male. To the present, the roles of dysregulated microRNAs in prostate cancer are still unclear. Here, we evaluated the anti-proliferative role of miR-378 in prostate cancer. And, we found that the expression of miR-378 was significantly downregulated in clinical prostate cancer tissues. In vitro assay suggested that overexpression of miR-378-suppressed prostate cancer cell migration and invasion promoted cell apoptosis. Furthermore, we identified and validated MAPK1 as a direct target of miR-378. Ectopic expression of MAPK1 rescues miR-378-suppressed cell migration and invasion. In vivo assay demonstrated that the stably miR-378-overexpressed prostate cancer cells displayed a significantly reduction in tumor growth. Taken together, our data suggested that miR-378 may act as a potential therapeutic target against human prostate cancer.

MiR-345 suppresses proliferation, migration and invasion by targeting Smad1 in human prostate cancer.

INTRODUCTION: The roles of dysregulated microRNAs in prostate cancer metastasis are still unknown. In this study, we found that the expression of miR-345 was significantly downregulated in prostate cancer and clinical prostate cancer tissues. MATERIALS, METHODS AND RESULTS: Overexpression of miR-345 in prostate cancer cells suppressed proliferation, migration and invasion. Using nude mice model, we revealed that miR-345 inhibits the growth of prostate cancer cells in vivo and in vitro. Furthermore, we identified and validated Smad1 as a direct target of miR-345. Ectopic expression of Smad1 without its 3'-UTR rescued miR-345-induced cell migration and invasion inhibition. CONCLUSION: Taken together, our data suggest that miR-345 exerts a suppressive effect on prostate cancer proliferation, invasion and migration through downregulation of Smad1.

Overexpression of RIN1 associates with tumor grade and progression in patients of bladder urothelial carcinoma.

Ras and Rab interactor 1 (RIN1) is an effector of H-Ras, which plays an important role in the development and progression of carcinomas, but it has not been reported in bladder cancer. Hence, the association of RIN1 expression with prognosis of bladder urothelial carcinoma (UC) was examined. RIN1 mRNA and protein expression in 20 paired UCs and the adjacent normal tissues was detected by quantitative reverse transcription polymerase chain reaction and Western blot. The expression of RIN1 protein in 96 specimens of UCs and 22 specimens of adjacent normal bladder tissues were analyzed by immunohistochemistry. The overall survival (OS) was assessed by univariate and multivariate analysis. Moreover, the progression-free survival (PFS) and recurrence-free survival (RFS), classified by the clinicopathologic features with RIN1 expression, were assessed by multivariate analysis. RIN1 mRNA and protein level was higher in UCs than in the adjacent normal tissues (P < 0.01). Enhanced RIN1 immunoexpression was associated with high histologic grades (P = 0.046), cancer progression (P = 0.047) as well as Ki-67 expression (P = 0.023). Furthermore, the 5-year survival rate was 29% in the subgroup with high level of RIN1 expression, while it was 43% in the subgroup with normal level of RIN1 expression (P < 0.05). Importantly, RIN1 level was revealed as the significant independent prognostic factor for death (P = 0.023) and progression (P = 0.003), but a weak contribution for recurrence (P = 0.063). Collectively, RIN1 expression could be a potential prognostic predictor for UC patients.

The role of zinc transporter ZIP4 in prostate carcinoma.

OBJECTIVE: Normal prostate tissues have a unique function of accumulating high levels of zinc. This capability is lost during the early stage in the development of prostate malignancy. ZIP4 is an important zinc transporter. In this study, we explore the expression of ZIP4 in prostate carcinoma and invest the functional contributions of ZIP4 to cancer growth in vitro. METHODS: ZIP4 expression was detected in 14 prostate carcinoma and 20 BPH tissues by real-time RT-PCR and western blot. To invest the biological function of ZIP4 in prostate carcinoma cells, ZIP4 stable over-expression in cells was established in prostate carcinoma cell line DU145 (DU145-ZIP4) and ZIP4 short hairpin RNA(shRNA) expression in stable cells was also established in prostate carcinoma cell line 22RV1(22RV1-shRNA). The proliferation, migration, and invasion ability of the prostate carcinoma cells were detected. RESULTS: The expression of ZIP4 mRNA and protein are significantly down-regulated in prostate carcinoma tissues compared with that in BPH tissues. However, we found that there was no correlation between the ZIP4 expression and the pathologic grade of prostate carcinoma. In in vitro studies, over-expression of ZIP4 not only inhibits the proliferation but also inhibits the invasive ability of prostate carcinoma cell line DU145-ZIP4. At the same time, we found silencing of ZIP4 was associated with increased cell proliferation and invasion ability in 22RV1-shRNA cell line. However, both DU145-ZIP4 and 22RV1-shRNA cells showed a significant reduction on cell migration ability compared with the control. CONCLUSION: The results indicate that ZIP4 expression is down-regulated in prostate carcinoma and it may serve as a promising biomarker for prostate carcinoma. ZIP4 has an inhibitory effect on prostate carcinoma cell proliferation and invasion. It suggests that ZIP4 may be a tumor suppressor gene and down-regulation of ZIP4 may be a critical early event in the development of prostate carcinoma.

Aberrant FHIT expression is linked to bladder carcinogenesis and apoptosis.

The fragile histidine triad gene (FHIT) functions as tumor suppressor in many epithelial cell types. Although the exact mechanisms remain unclear, it is apparent that in its absence, cell cycle homeostasis is often perturbed resulting in the development of soft tissue tumors. Here, we investigated the role of FHIT expression in bladder carcinogenesis and progression using immunohistochemistry. Bladder carcinoma tissue and the 5637 cell line were also studied for FHIT expression by RT-PCR and Western blotting, respectively. FHIT was found to be expressed in carcinoma and adjacent normal tissues at both mRNA and protein levels, but the 17 kDa FHIT was lower in tumors (P<0.05), this being confirmed immunohistochemically. There was a negative correlation between FHIT expression and histological grade of bladder transitional cell carcinoma (P<0.05), but no clear relationship with clinical stage or relapse (P>0.05). Overexpression of FHIT could induce apoptosis in bladder carcinoma 5637 cells, which could be enhanced by adding adriamycin (ADR). These findings suggest important roles of FHIT in bladder cancer development and provide support for the feasibility of FHIT-based gene therapy.