Outcome of Muscle-Invasive Urothelial Bladder Cancer After Radical Cystectomy

Nationwide analysis of survival after radical cystectomy for bladder cancer in Finland

BACKGROUND

Population-based survival results after radical cystectomy (RC) are limited. Our objective was to report short and long-term survival results after RC for bladder cancer from Finland in a population-based setting.

MATERIALS AND METHODS

The Finnish National Cystectomy Database containing retrospectively collected essential RC data covering the years 2005-2017 was combined with the survival data from the Finnish Cancer Registry. Kaplan-Meier plots were used to estimate survival and the survival graphs were illustrated according to the final pathological staging. Centers were divided according to operational volume, and the results were then compared using Pearsons's Chi-squared test.

RESULTS

A total of 2047 patients were included in the study. 30-, and 90-day mortality was 1.3%, and 3.8%, respectively. The OS of the entire RC population at 5- and 10 years was 66% and 55%, and CSS was 74% and 72%, respectively. Center volume did not significantly associate with surgical mortality or long-term survival. The 5- and 10-year OS according to pT-category was 87% and 74% for pT0, 85% and 69% for pTa-pTis-pT1, 70% and 58% for pT2, 50% and 42% for pT3 and 41% and 30% for pT4. The corresponding 5- and 10-year CSS rates were 96% and 93% for pT0, 91% and 90% for pTa-pTis-pT1, 78% and 75% for pT2, 56% and 55% for pT3 and 47% and 44% for pT4. The 5- and 10-year OS rates in patients with no lymph node metastases (pN-) were 74% and 62%, and CSS 82% and 80%, respectively. If lymph nodes were positive (pN+), the corresponding OS rates were 44% and 34% and CSS 49% and 48%, respectively.

CONCLUSION

RC survival results have improved in contemporary series and are associated with the pTNM-status. The nationwide results from Finland demonstrate outcome comparable to high volume single-center series.

PPM-18, an Analog of Vitamin K, Induces Autophagy and Apoptosis in Bladder Cancer Cells Through ROS and AMPK Signaling Pathways

PPM-18, identified as a novel analog of vitamin K, has been reported to play a critical role in the suppression of seizures. However, the concerns that whether PPM-18, like vitamin K, exerts anticancer activity remain to be further investigated. Here, we found that PPM-18 remarkably suppressed the proliferation and induced apoptosis in bladder cancer cells. Furthermore, a significant autophagic effect of PPM-18 on bladder cancer cells was also demonstrated, which profoundly promoted apoptotic cell death. Mechanistically, PPM-18 activated AMP-activated protein kinase (AMPK), whereas it repressed PI3K/AKT and mTORC1 pathways in bladder cancer cells. Inhibition of AMPK markedly relieved PPM-18–induced autophagy and apoptosis, indicating that PPM-18 is able to induce autophagy and apoptosis in bladder cancer cells via AMPK activation. Moreover, reactive oxygen species (ROS) were notably accumulated in PPM-18–treated bladder cancer cells, and treatment with ROS scavengers not only eliminated ROS production but also abrogated AMPK activation, which eventually rescued bladder cancer cells from PPM-18–triggered autophagy and apoptotic cell death. In bladder cancer xenografts, the anticancer activities of PPM-18, including suppressing the growth of tumors and inducing autophagy and apoptosis in tumor cells, were also established. Collectively, this study was the first to demonstrate the anticancer effect of PPM-18 on bladder cancer cells in vitro and in vivo through eliciting autophagy and apoptosis via ROS and AMPK pathways, which might provide new insights into the potential utilization of PPM-18 for future bladder cancer treatment.

ACR Appropriateness Criteria® Post-Treatment Surveillance of Bladder Cancer: 2021 Update

Urothelial cancer is the second most common cancer, and cause of cancer death, related to the genitourinary tract. The goals of surveillance imaging after the treatment of urothelial cancer of the urinary bladder are to detect new or previously undetected urothelial tumors, to identify metastatic disease, and to evaluate for complications of therapy. For surveillance, patients can be stratified into one of three groups: 1) nonmuscle invasive bladder cancer with no symptoms or additional risk factors; 2) nonmuscle invasive bladder cancer with symptoms or additional risk factors; and 3) muscle invasive bladder cancer. This document is a review of the current literature for urothelial cancer and resulting recommendations for surveillance imaging. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

The inhibitory effect of silencing CDCA3 on migration and proliferation in bladder urothelial carcinoma

Background

CDCA3 is an important component of the E3 ligase complex with SKP1 and CUL1, which could regulate the progress of cell mitosis. CDCA3 has been widely identified as a proto-oncogene in multiple human cancers, however, its role in promoting human bladder urothelial carcinoma has not been fully elucidated.

Methods

Bioinformatic methods were used to analyze the expression level of CDCA3 in human bladder urothelial carcinoma tissues and the relationship between its expression level and key clinical characteristics. In vitro studies were performed to validate the specific functions of CDCA3 in regulating cell proliferation, cell migration and cell cycle process. Alterations of related proteins was investigated by western blot assays. In vivo studies were constructed to validate whether silencing CDCA3 could inhibit the proliferation rate in mice model.

Results

Bioinformatic analysis revealed that CDCA3 was significantly up-regulated in bladder urothelial carcinoma samples and was related to key clinical characteristics, such as tumor grade and metastasis. Moreover, patients who had higher expression level of CDCA3 tend to show a shorter life span. In vitro studies revealed that silencing CDCA3 could impair the migration ability of tumor cells via down-regulating EMT-related proteins such as MMP9 and Vimentin and inhibit tumor cell growth via arresting cells in the G1 cell cycle phase through regulating cell cycle related proteins like p21. In vivo study confirmed that silencing CDCA3 could inhibit the proliferation of bladder urothelial carcinoma cells.

Conclusions

CDCA3 is an important oncogene that could strengthen the migration ability of bladder urothelial carcinoma cells and accelerate tumor cell growth via regulating cell cycle progress and is a potential biomarker of bladder urothelial carcinoma.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-01969-x.

ACR Appropriateness Criteria® Post-Treatment Surveillance of Bladder Cancer

Urothelial cancer is the second most common cancer, and cause of cancer death, related to the genitourinary tract. The goals of surveillance imaging after the treatment of urothelial cancer of the urinary bladder are to detect new or previously undetected urothelial tumors, to identify metastatic disease, and to evaluate for complications of therapy. For surveillance, patients can be stratified into one of three groups: (1) nonmuscle invasive bladder cancer with no symptoms or additional risk factors; (2) nonmuscle invasive bladder cancer with symptoms or additional risk factors; and (3) muscle invasive bladder cancer. This article is a review of the current literature for urothelial cancer and resulting recommendations for surveillance imaging. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Downstaging of Muscle-Invasive Bladder Cancer Using Neoadjuvant Gemcitabine and Cisplatin or Dose-Dense Methotrexate, Vinblastine, Doxorubicin, and Cisplatin as Single Regimens or as Switch Therapy Modalities

BACKGROUND

Consensus guidelines recommend gemcitabine and cisplatin (GC) or dose-dense methotrexate, vinblastine, doxorubicin, and cisplatin (ddMVAC) as equally preferable neoadjuvant chemotherapy before cystectomy for muscle-invasive bladder cancer. This study sought to compare the ability of GC and ddMVAC to achieve pathologic response; and to evaluate the benefit of switching regimens after 1 or 2 cycles of the other.

PATIENTS AND METHODS

Patients aged ≥ 18 with muscle-invasive bladder cancer (≥ cT2) and who had received either GC or ddMVAC as neoadjuvant chemotherapy followed by cystectomy were retrospectively evaluated using the electronic medical record. Patients who received 1 or 2 cycles of one regimen followed by several cycles of the other regimen before cystectomy were classified as switch therapy patients. This study assessed the rates of pathologic complete response (pCR) and any degree of downstaging.

RESULTS

Among 109 patients who received GC or ddMVAC, 7 (21%) of 33 ddMVAC patients demonstrated pCR, and 19 (25%) of 76 GC patients demonstrated pCR (odds ratio, 1.24; 95% confidence interval, 0.46-3.31; P = .67). Downstaging rates were 39% for ddMVAC and 50% for GC (P = .31). Thirty-three of 36 patients aged ≥ 70 years received GC (P < .001). Four of 7 patients treated with switch therapy showed downstaging, and 2 of 7 experienced pCR.

CONCLUSION

There was no difference in pCR rates between GC and ddMVAC, and patients were most often able to receive 3 or 4 cycles of treatment. Switch therapy may be of benefit in patients whose disease has a poor initial response.

RNA-Binding Protein ZFP36L1 Suppresses Hypoxia and Cell-Cycle Signaling

ZFP36L1 is a tandem zinc-finger RNA-binding protein that recognizes conserved adenylate-uridylate-rich elements (ARE) located in 3'untranslated regions (UTR) to mediate mRNA decay. We hypothesized that ZFP36L1 is a negative regulator of a posttranscriptional hub involved in mRNA half-life regulation of cancer-related transcripts. Analysis of in silico data revealed that ZFP36L1 was significantly mutated, epigenetically silenced, and downregulated in a variety of cancers. Forced expression of ZFP36L1 in cancer cells markedly reduced cell proliferation in vitro and in vivo, whereas silencing of ZFP36L1 enhanced tumor cell growth. To identify direct downstream targets of ZFP36L1, systematic screening using RNA pull-down of wild-type and mutant ZFP36L1 as well as whole transcriptome sequencing of bladder cancer cells {plus minus} tet-on ZFP36L1 was performed. A network of 1,410 genes was identified as potential direct targets of ZFP36L1. These targets included a number of key oncogenic transcripts such as HIF1A, CCND1, and E2F1. ZFP36L1 specifically bound to the 3'UTRs of these targets for mRNA degradation, thus suppressing their expression. Dual luciferase reporter assays and RNA electrophoretic mobility shift assays showed that wild-type, but not zinc-finger mutant ZFP36L1, bound to HIF1A 3'UTR and mediated HIF1A mRNA degradation, leading to reduced expression of HIF1A and its downstream targets. Collectively, our findings reveal an indispensable role of ZFP36L1 as a posttranscriptional safeguard against aberrant hypoxic signaling and abnormal cell-cycle progression. SIGNIFICANCE: RNA-binding protein ZFP36L1 functions as a tumor suppressor by regulating the mRNA stability of a number of mRNAs involved in hypoxia and cell-cycle signaling.

Incidence and risk factors for peritoneal carcinomatosis following open radical cystectomy

OBJECTIVE

To characterize the frequency and risk factors of peritoneal carcinomatosis (PC) in patients undergoing open radical cystectomy (RC).

METHODS

We identified 3,285 patients with urothelial carcinoma treated with RC for curative intent between 1980 and 2016. At last follow-up, 72.1% (2,370/3,285) of patients had died, with a median follow-up of 8.6 years (Interquartile Range, (IQR) 3.7, 14.1). PC was defined as any recurrence involving the omentum, small bowel, and mesentery. Overall-specific survival (OSS) and cancer-specific survival (CSS) was evaluated using Kaplan-Meier methodology and log-rank test. Risk factors for mortality and recurrence were performed using Cox proportional hazards regression models.

RESULTS

One hundred and twenty nine (3.9%) patients were diagnosed with PC, while a total of 1,148 (34.9%) patients experienced recurrence at other sites. Median time to PC vs. other-site recurrence was 1.3 (IQR 1.3, 2.3) and 0.9 (IQR 0.5, 2.1) years, respectively (P= 0.04). Only increasing pathologic stage on multivariable analysis was associated with developing PC (pT1 HR 2.51, 95CI 1.14-5.55, P= 0.02; pT2 OR 2.82, 95CI 1.47-5.43, P= 0.002; pT3+ 2.40, 95CI 1.31-4.42, P= 0.005) over other recurrence patterns. Nodal status and tumor margin status were not associated. Patients with PC experienced worse OSS and CSS than other types of recurrence (P< 0.001).

CONCLUSION

PC was identified in almost 4% of patients undergoing open RC. PC is a rare occurrence after RC and primarily impacts patients with locally advanced disease.

Clinical significance of urothelial carcinoma ambiguous for muscularis propria invasion on initial transurethral resection of bladder tumor

PURPOSE

To evaluate the clinical significance of invasive urothelial carcinoma that is ambiguous for muscularis propria invasion on initial transurethral resection of bladder tumor (TURBT).

METHODS

All consecutive in-house TURBTs with invasive urothelial carcinoma from 1999 to 2017 that underwent radical cystectomy (RC) were grouped as follows: invasion of the lamina propria (INLP; n = 102; 24%), invasion of muscularis propria (INMP; n = 296; 69%) and ambiguous for muscularis propria invasion (AMP; n = 30; 7%). AMP was defined as extensive invasive carcinoma displaying thin muscle bundles where it is difficult to determine with certainty if those muscle bundles represent muscularis mucosae or muscularis propria (detrusor). Cases with any amount of small cell carcinoma or prior therapy were excluded.

RESULTS

The average age was 66 years in INLP, 67 years in INMP, and 65 years in AMP. RC showed invasive carcinoma stage pT2 or above in 50/102 (49%) of INLP vs. 255/296 (86%) of INMP (P ≤ 001) vs. 25/30 (83.33%) of AMP (P = 0.002). Lymph nodes showed metastatic carcinoma in 18/98 (18.36%) of INLP vs. 96/272 (35.29%) of INMP (P = 0.002), and 6/25 (24%) in AMP (P = 0.729). The average follow-up was 48 months (range 0-192). Survival of AMP patients was similar to INLP and both were significantly better than INMP (P = 0.002 and P = 0.016).

CONCLUSION

The great majority of patients with AMP on initial TURBT have advanced disease on RC and emphasizes the need for early repeat TURBT or even consideration of early cystectomy to lower the risk of worse pathological findings and to prolong survival.

Evaluation of lymph node status in patients with urothelial carcinoma-still in search of the perfect imaging modality: a systematic review

While accurate lymph node status evaluation in urothelial carcinoma patients is essential for the correct disease staging and, hence, establishing the most beneficial treatment strategy, the diagnostic performance of routine imaging in regards to this issue is not satisfactory. For the purpose of this article, we systematically reviewed the contemporary literature on the sensitivity and specificity of particular imaging modalities which have been studied for detecting lymph node metastases in patients diagnosed with urothelial carcinoma. The evidence reviewed shows that computed tomography (CT), although recognized as the imaging modality of choice, is associated with marked limitations, resulting in its low sensitivity for lymph node involvement detection in urothelial carcinoma patients, with no study reporting a value higher than 46% using standard cut-off values. Markedly higher sensitivity rates may be achieved with magnetic resonance imaging (MRI), especially when using ultrasmall superparamagnetic iron oxide as the contrast agent, however, no uniform protocol has been systematically studied up to date. The vast majority of recent evidence concerns positron emission tomography (PET), which is being reported to improve the diagnostic performance of CT alone, as has been demonstrated in multiple articles, which investigated the accuracy of PET/CT at primary or post-treatment staging of urothelial carcinoma patients. However, there has been substantial heterogeneity in terms of methodology and results between those studies, making it premature to draw any definitive conclusions. The results of this review lead to a conclusion, that while CT, despite being not fully satisfactory, still remains the gold-standard method of imaging for staging purposes in urothelial carcinoma, other imaging modalities are under investigation, with promising results.

CDCA8 expression and its clinical relevance in patients with bladder cancer

Cell division cycle associated 8 (CDCA8) overexpression is detected in various malignant tumors and closely associated with tumor growth. However, the correlations of CDCA8 expression with clinicopathological factors and prognosis of bladder cancer (BC) remain unclear. The purpose of this study was to identify the expression of CDCA8 and its clinical relevance in BC patients.GEO datasets were employed to obtain CDCA8 expression data and its clinical information in BC samples. Real-time PCR (RT-PCR) was performed to detect the expression of CDCA8 in BC and the adjacent normal tissues. Nonpaired t test was used to statistically analyze the difference between the 2 groups. Cox univariable and multivariable analyses of overall survival (OS) and cancer specific survival (CSS) among BC patients were performed. Biological processes or signaling pathways that might mediate the activity of CDCA8 in BC were analyzed.CDCA8 levels were significantly higher in BC (8.870 ± 0.08281 vs 7.472 ± 0.07035, P < .0001). CDCA8 expression was significantly associated with tumor progression (P = .001), T stage (P < .0001), N stage (P = .013), and grade (P < .0001). Higher expression of CDCA8 predicted poor cancer-specific survival (P < .0001, HR = 0.2752, 95% CI:0.1364-0.5554) and overall survival (P < .0001, HR = 0.4270, 95% CI: 0.2630-0.6930) in patients with BC. Cox univariable and multivariable analyses showed that intravesical therapy, N stage and progression were the independent influence factors of overall survival among bladder cancer patients, CDCA8 expression, tumor grade and progression were the independent influence factors of cancer specific survival among bladder cancer patients. The results of GSEA indicated that CDCA8-regulated gene sets associated with spermatogenesis, G2M checkpoint, E2F targets, Myc targets, mTORC1 signaling, mitotic spindle angiogenesis, PI3K/AKT/mTOR signaling, cholesterol homeostasis and glycolysis. Finally, RT-PCR results confirmed that CDCA8 expression was upregulated in BC (P = .0039).CDCA8 is overexpressed in BC and its high levels are correlated with poor clinicopathological features of BC patients. Therefore, CDCA8 may act as a novel prognostic marker and therapeutical target in the diagnosis and treatment of patients with BC.

A systematic review and meta-analysis of lymphovascular invasion in patients treated with radical cystectomy for bladder cancer

PURPOSE

Lymphovascular invasion (LVI) is an important step in bladder cancer cell dissemination. We aimed to perform a systematic review and meta-analysis of the literature to assess the prognostic value of LVI in radical cystectomy (RC) specimens.

PATIENTS AND METHODS

A systematic review and meta-analysis of the last 10 years was performed using the MEDLINE, EMBASE, and the Cochrane libraries in July 2017. The analyses were performed in accordance with the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) statement.

RESULTS

We retrieved 65 studies (including 78,107 patients) evaluating the effect of LVI on oncologic outcomes in patients treated with RC. LVI was reported in 35.4% of patients. LVI was associated with disease recurrence (pooled hazard ratio [HR] = 1.57; 95% CI: 1.45-1.70) and cancer-specific mortality (CSM) (pooled HR = 1.59; 95% CI: 1.48-1.73) in all studies regardless of tumor stage and node status (pT1-4 pN0-2). LVI was associated with recurrence and CSM in patients with node-negative bladder cancer (BC). In patients with node-negative BC, LVI rate increased and was associated with worse oncologic outcome. LVI had a lower but still significant association with disease recurrence and CSM in node-positive BC.

CONCLUSIONS

LVI is a strong prognostic factor of worse prognosis in patients treated with RC for bladder cancer. This association is strongest in node-negative BC, but it is also in node-positive BC. LVI should be part of all pathological reporting and could provide additional information for treatment-decision making regarding adjuvant therapy after RC.

Identification of Biomarkers Correlated with the TNM Staging and Overall Survival of Patients with Bladder Cancer

Objective: To identify candidate biomarkers correlated with clinical prognosis of patients with bladder cancer (BC). Methods: Weighted gene co-expression network analysis was applied to build a co-expression network to identify hub genes correlated with tumor node metastasis (TNM) staging of BC patients. Functional enrichment analysis was conducted to functionally annotate the hub genes. Protein-protein interaction network analysis of hub genes was performed to identify the interactions among the hub genes. Survival analyses were conducted to characterize the role of hub genes on the survival of BC patients. Gene set enrichment analyses were conducted to find the potential mechanisms involved in the tumor proliferation promoted by hub genes. Results: Based on the results of topological overlap measure based clustering and the inclusion criteria, top 50 hub genes were identified. Hub genes were enriched in cell proliferation associated gene ontology terms (mitotic sister chromatid segregation, mitotic cell cycle and, cell cycle, etc.) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways (cell cycle, Oocyte meiosis, etc.). 17 hub genes were found to interact with ≥5 of the hub genes. Survival analysis of hub genes suggested that lower expression of MMP11, COL5A2, CDC25B, TOP2A, CENPF, CDCA3, TK1, TPX2, CDCA8, AEBP1, and FOXM1were associated with better overall survival of BC patients. BC samples with higher expression of hub genes were enriched in gene sets associated with P53 pathway, apical junction, mitotic spindle, G2M checkpoint, and myogenesis, etc. Conclusions: We identified several candidate biomarkers correlated with the TNM staging and overall survival of BC patients. Accordingly, they might be used as potential diagnostic biomarkers and therapeutic targets with clinical utility.

Predictors of female genital organ involvement in radical cystectomy for urothelial carcinoma of the bladder: A single-center retrospective analysis of 112 female patients

OBJECTIVES

To evaluate predictors of organ involvement and oncological outcomes after radical cystectomy with anterior exenteration in female patients.

METHODS

Among 1198 patients who underwent radical cystectomy for the bladder tumor between 1990 and 2015, 178 (14.9%) patients were female. They were divided into two groups according to pelvic involvement in pathology. Their medical records and pathology and image findings were reviewed retrospectively. Non-urothelial cell carcinoma and no genital organ pathology were excluded. Multivariate logistic regression was performed to predict factors associated with female organ involvement.

RESULTS

Out of 112 eligible female patients with urothelial cell carcinoma, 11 (9.8%) had female genital organ involvement. Female genital organ involvement occurred primarily in the uterus (63.6%) mostly. The 5-year overall survival rates were 67.3% in the non-involvement group and 18.9% in the involvement group. On multivariate analysis Tumor location of trigone or bladder neck at transurethral resection of bladder tumor (TUR-B) (odds ratio [OR] 19.84, 95% confidence interval [CI] 2.89-230.68, p = 0.0056), maximum tumor size at computed tomography (CT) (OR 2.17, 95% CI 1.29-4.34, p = 0.0095), and hydronephrosis at CT (OR 17.61, 95% CI 2.28-296.26, p = 0.0158) were associated with female organ involvement.

CONCLUSIONS

Tumor location of trigone or bladder neck at TUR-B, maximum tumor size at CT or hydronephrosis at CT were significant factors to predict female genital organ involvement. Preoperative recognition of female genital organ involvement could increase the decision to perform genital organ-sparing surgeries.

Advances in surgical management of muscle invasive bladder cancer

INTRODUCTION

Bladder cancer remains a disease of the elderly with relatively few advances that have improved survival over the last 20 years. Radical cystectomy (RC) has long remained the principal treatment for muscle-invasive bladder cancer (MIBC).

METHODS

A literature search of PubMed was performed. The content was reviewed for continuity with the topic of surgical advances in MIBC. Articles and society guidelines were included in this review.

RESULTS

Despite the associated morbidity, even in the elderly, RC is still a reasonable option. Modifications during RC may have a positive or negative impact on survival and quality of life. The extent of pelvic lymph node dissection is one such factor which may positively impact survival outcomes. In addition, preservation of pelvic organs, robotic surgery and the adoption of enhanced recovery after surgery principles continues to improve the postoperative recovery and quality of life in RC patients.

CONCLUSION

There are some ongoing studies in many of these areas, but overall the new advances in MIBC may improve patient quality and quantity of life. The advances in surgical treatment of MIBC are important and the focus of the review here.

microRNA-495 promotes bladder cancer cell growth and invasion by targeting phosphatase and tensin homolog

Accumulating evidence has linked deregulation of microRNA-495 (miR-495) to tumorigenesis; however, its function in tumor progression is controversial. This work was undertaken to explore the expression and biological roles of miR-495 in bladder cancer. The expression of miR-495 was examined in 67 pairs of bladder cancer and adjacent normal bladder tissues. The roles of miR-495 in bladder cancer cell proliferation and invasion in vitro and tumorigenesis in vivo were determined. Direct target gene(s) mediating the activity of miR-495 in bladder cancer cells was identified. It was found that miR-495 was expressed at greater levels in bladder tissues and cell lines. High expression of miR-495 was significantly associated with larger tumor size, advanced TNM stage, and lymph node metastasis. Overexpression of miR-495 significantly promoted bladder cancer cell proliferation and invasion, whereas inhibition of miR-495 suppressed cell proliferation and invasion. PTEN, a well-defined tumor suppressor was identified to be a target gene of miR-495. A significant inverse correlation between miR-495 and PTEN expression was noted in bladder cancer tissues (r = -0.3094, P = 0.0125). Overexpression of miR-495 led to reduction of PTEN expression in bladder cancer cells. Rescue experiments showed that enforced expression of PTEN impaired miR-495-mediated bladder cancer proliferation and invasion. In vivo mouse studies demonstrated that overexpression of miR-495 accelerated the growth of subcutaneous bladder cancer xenografts, which was associated with downregulation of PTEN. Overall, these findings indicate that miR-495 upregulation contributes to bladder cancer cell growth, invasion, and tumorigenesis by targeting PTEN and offer a potential therapeutic target for bladder cancer.