Differential effect on survival of pelvic lymph node dissection at radical cystectomy for muscle invasive bladder cancer

Bladder Cancer: Immunotherapy and Pelvic Lymph Node Dissection

Bladder cancer, a common malignancy of the urinary system, is routinely treated with radiation, chemotherapy, and surgical excision. However, these strategies have inherent limitations and may also result in various side effects. Immunotherapy has garnered considerable attention in recent years as a novel therapeutic approach. It harnesses and activates the patient's immune system to recognize and eliminate cancer cells, which not only prolongs therapeutic efficacy but also minimizes the toxic side effects. Several immune checkpoint inhibitors and cancer vaccines have been developed for the treatment of bladder cancer. Whereas blocking immune checkpoints on the surface of tumor cells augments the effect of immune cells, immunization with tumor-specific antigens can elicit the production of anti-tumor immune effector cells. However, there are several challenges in applying immunotherapy against bladder cancer. For instance, the efficacy of immunotherapy varies considerably across individual patients, and only a small percentage of cancer patients are responsive. Therefore, it is crucial to identify biomarkers that can predict the efficacy of immunotherapy. Pelvic lymph nodes are routinely dissected from bladder cancer patients during surgical intervention in order to remove any metastatic tumor cells. However, some studies indicate that pelvic lymph node dissection may reduce the efficacy of immunotherapy by damaging the immune cells. Therefore, the decision to undertake pelvic lymph node removal should be incumbent on the clinical characteristics of individual patients. Thus, although immunotherapy has the advantages of lower toxic side effects and long-lasting efficacy, its application in bladder cancer still faces challenges, such as the lack of predictive biomarkers and the effects of pelvic lymph node dissection. Further research is needed to explore these issues in order to improve the efficacy of immunotherapy for bladder cancer.

Adequate Pelvic Lymph Node Dissection in Radical Cystectomy in the Era of Neoadjuvant Chemotherapy: A Meta-Analysis and Systematic Review

Radical cystectomy (RC) with pelvic lymphadenectomy (PLND) serves as the gold-standard treatment for muscle-invasive bladder cancer (MIBC). Numerous studies have shown that the number of lymph nodes (LN) removed during RC could affect patient prognosis. However, these studies confirmed the association between PLND and survival outcomes prior to the widespread adoption of neoadjuvant chemotherapy (NAC). Consequently, this study aimed to investigate the prognostic role of PLND in patients previously pretreated with NAC. A systematic review and meta-analysis were performed using PubMed, Web of Knowledge, and Scopus databases. The selected studies contained a total of 17,421 participants. The meta-analysis indicated a significant correlation between adequate PLND and overall survival in the non-NAC group. However, a survival benefit was not observed in patients undergoing RC with preoperative systemic therapy, regardless of the LN cut-off thresholds. The pooled HR for ≥10 and ≥15 LN were 0.87 (95% CI 0.75-1.01) and 0.87 (95% CI 0.76-1.00), respectively. The study results suggest that NAC mitigates the therapeutic significance of PLND, as patients pre-treated with NAC no longer gain oncological benefits from more extensive lymphadenectomy. This highlights the analogous roles of NAC and PLND in eradication of micrometastases and in prevention of distal recurrence post-RC.

Extent of lymph node dissection and impact on survival in radical cystectomy for advanced bladder cancer

PURPOSE OF REVIEW

In patients with muscle invasive bladder cancer (MIBC) or unresectable non-MIBC, radical cystectomy is routinely combined with bilateral pelvic lymph node dissection (LND) owing to the oncological benefits found in recurrence-free survival (RFS), overall survival (OS) and cancer-specific survival (CSS) compared with radical cystectomy alone. However, the optimal anatomic extent of LND is still unclear.

RECENT FINDINGS

Retrospective studies were consistent in reporting oncological benefits of extended LND over nonextended LND. A recent RCT (the LEA trial) failed to demonstrate any benefit in terms of RFS, CSS and OS of super-extended LND over standard LND. Several confounding factors hindered the interpretation of the results, leaving the question of the right extent for LND still open. Results of a similar study, the SWOG S1011 are, therefore, highly anticipated. This study differed from the LEA study in several aspects but might also turn out to be a negative study.

SUMMARY

There are still no firm data on the oncological benefit brought by more extended LND in patients with MIBC. Survival benefits seem limited, at least in the general population. Other factors could influence the impact of LND on survival, including the administration of adjuvant and neoadjuvant chemotherapies.

Young age increases the risk of lymph node positivity but improves prognosis in patients with bladder cancer treated via cystectomy: a population-based study

Background

Age and lymph node positivity are significant prognostic indicators in patients with bladder cancer. This study aimed to investigate the impact of age on lymph node positivity and bladder cancer outcomes.

Methods

Patients with bladder cancer who underwent cystectomy with at least one lymph node examined between 2004 and 2015 were identified from the Surveillance, Epidemiology, and End Results database. Cochran-Armitage trend tests and logistic regression analyses were used to evaluate the association between age and lymph node positivity in all T stages. Multivariate Cox regression analysis was used to analyze the effect of age on overall survival (OS) and cancer-specific survival (CSS).

Results

Overall, 13,251 patients were identified, 648 of whom were under 50 years of age (4.89%). Lymph node positivity was negatively associated with increasing age in each stage except in non-invasive-muscular bladder cancer. In the multivariable analysis, age was an independent prognostic factor for OS and CSS in both the overall cohort and the lymph node positivity group.

Conclusions

In patients with bladder cancer undergoing cystectomy, young age at diagnosis is associated with a higher risk of lymph node positivity and superior outcomes. These findings may guide clinicians in selecting suitable treatments, determining the aggressiveness of lymph node involvement, and predicting survival outcomes in patients of different ages.

The Usefulness of Lymphadenectomy in Bladder Cancer-Current Status

The purpose of this review is to present the current status of lymph node dissection (LND) during radical cystectomy in patients with bladder cancer (BCa). Despite the growing body of evidence of LND utility at the time of radical cystectomy (RC) in high-risk nonmuscle-invasive and muscle-invasive BCa (MIBC), therapeutic and prognostic value and optimal extent of LND remain unsolved issues. Recently published results of the first prospective, a randomized trial assessing the therapeutic benefit of extended versus limited LND during RC, failed to demonstrate survival improvement with the extended template. Although LND is the most accurate staging procedure, the direct therapeutic effect is still not evident from the current literature, limiting the possibility of establishing clear recommendations. This indicates the need for robust and adequately powered clinical trials.

Young age increases the risk of lymph-node metastasis in patients with muscle-invasive bladder urothelial carcinoma

BACKGROUND

The risk of positive lymph nodes in patients with muscle-invasive bladder urothelial carcinoma (MIBC) can be used to guide treatment recommendations. However, little is known about the effect of age on lymph node positivity (LN+). This study aimed to evaluate the effect of age on LN+ in MIBC.

METHODS

We analyzed patients with stage T2-T4 bladder urothelial carcinoma who had not received preoperative radiotherapy, had at least one lymph node examined, and underwent cystectomy between 1998 and 2015. The Cochran-Armitage trend test and logistic univariate and multivariate analyses were used to evaluate the effect of age on LN+ in all T stages.

RESULTS

In total, 15,624 patients with MIBC were identified, including 747 patients aged ≤50 years (4.78%), 2614 patients aged 50-59 years (16.73%), 4914 patients aged 60-69 years (31.45%), 5225 patients aged 70-79 years old (33.44%), and 2124 patients aged > 80 years (13.59%). In T2-T4 staging, LN+ was negatively correlated with age. After adjustment for several covariates, multivariate logistic regression analysis revealed that age was an independent risk factor for LN+.

CONCLUSIONS

In this large SEER analysis, Young patients with MIBC have a higher risk of lymph node metastasis. This finding is worthy of further study and may eventually affect the treatment decisions of young patients.

Clinical markers of morbidity, mortality and survival in bladder cancer patients treated with radical cystectomy. A systematic review

Context: Radical cystectomy and pelvic lymph node dissection (RC and PLND) are an essential part of the treatment paradigm in high risk bladder cancer. However, these patients have high rates of morbidity and mortality related both to the treatment and to the disease.Objective: To provide overview of current literature about clinical markers that can be used to predict and improve BC-patient outcomes at the time of RC and PLND and to study if they are properly validated.Evidence acquisition: A systematic literature search was conducted according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) criteria between January 1990 and October 2018 to identify English written original and review articles relevant to this topic. Prospective and retrospective studies were included.Evidence synthesis: There are several risk factors identified from non-randomised trials that can be improved before surgery to reduce perioperative mortality and morbidity. These include poor nutritional status, anaemia, renal function and smoking. Preoperative nomograms have also been developed to help decision-making and to inform patients about the risks of surgery. They can be used to estimate risk of postoperative mortality after RC and PLND with accuracy varying from 70 to 86%. These nomograms are largely based on retrospective data. Likewise, nomograms developed to calculate estimates about patient's overall and cancer specific survival have the same limitations.Conclusion: Clinical markers to predict morbidity, mortality and survival in patients with bladder cancer treated with RC and PLND may help to improve patient outcomes and treatment decision-making, but available data come from small retrospective trials and have not been properly validated. Prospective, multi-centre studies are needed to implement and disseminate predictive clinical markers and nomograms such that they can be utilised in treatment decision-making in daily practice.

Pelvic lymph node dissection during radical cystectomy for muscle-invasive bladder cancer

Radical cystectomy is the gold-standard treatment option for muscle-invasive and metastatic bladder cancer. At the time of cystectomy, up to 25% of patients harbour metastatic lymph node deposits. These deposits most frequently occur in the obturator fossa, but can be as proximal as the interaortocaval region. Thus, the use of concurrent pelvic lymph node dissection (PLND) with cystectomy has been increasingly reported. Data from studies including many patients suggest substantial oncological benefit in PLND cohorts versus non-PLND cohorts, irrespective of pathological nodal status. Additionally, PLND provides useful prognostic information, including disease burden, lymph node density, and extracapsular extension of metastatic lymph nodes. Accordingly, the National Comprehensive Cancer Network guidelines advocate the use of PLND during radical cystectomy for muscle-invasive bladder cancer. Despite this recommendation, a lack of consensus exists regarding the optimal PLND template. Comparative series suggest that extended PLND provides improved recurrence-free survival and cancer-specific survival compared with more limited PLND templates. More extensive templates (such as super-extended PLND) provide no additional survival benefit at the potential cost of increased operative time and patient morbidity. In addition to extended PLND templates, increased nodal harvest confers an oncological benefit in patients with node-positive disease or in patients with node-negative disease. Accordingly, recommendations for a minimum nodal yield have been proposed. Despite the growing body of evidence, formal recommendations by oncological and urological authoritative bodies have been limited owing to the lack of randomized data and level I evidence.

Development and Validation of an Improved Pathological Nodal Staging System for Urothelial Carcinoma of the Bladder

BACKGROUND

Current pathological nodal staging for bladder cancer is based on lymph node (LN) location but not on the number of positive LNs.

OBJECTIVE

We sought to improve prognostic classification by creating a novel staging system incorporating positive LN burden.

DESIGN, SETTING, AND PARTICIPANTS

We sampled 12515 patients with muscle-invasive bladder cancer (MIBC) from the National Cancer Database (NCDB) and 5928 MIBC patients from the Surveillance, Epidemiology, and End Results (SEER) database for our development and validation cohorts, respectively.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Multivariable Cox proportional hazards analysis with restricted cubic splines was used to assess the association between the number of metastatic LNs and overall mortality (OM). A novel staging system was derived by recursive partitioning analysis (RPA) in NCDB and was validated in SEER by assessing discrimination (Harrel's c-index) and calibration (mean absolute prediction error).

RESULTS AND LIMITATIONS

Mortality risk increased continuously with more metastatic LNs; the effect was most pronounced up to four LNs (hazard ratio [HR] 1.17, 95% confidence interval [CI] 1.12-1.22) and attenuated beyond four nodes (HR 1.03, 95% CI 1.02-1.05). RPA generated a novel staging system predicting mortality by metastatic nodal number with cutpoints at zero (reference), one (HR 1.57, 95% CI 1.46-1.69), two to three (HR 2.03, 95% CI 1.88-2.19), four to seven (HR 2.46, 95% CI 2.25-2.70), and more than seven (HR 3.83, 95% CI 3.38-4.33) positive LNs. Location of LN involvement was not a significant predictor of OM. In external validation, the novel staging system showed good risk discrimination (optimism corrected c-index 0.677, 95% CI 0.672-0.682) and calibration (mean absolute prediction error 0.011 for 5-yr OM). Results are limited by development and validation using secondary data.

CONCLUSIONS

The number of metastatic LNs predicts mortality better than LN location and may improve pathological nodal staging in MIBC.

PATIENT SUMMARY

This retrospective study found that the number of metastatic lymph nodes more accurately predicts survival than the location of metastatic lymph nodes in patients with muscle-invasive bladder cancer. This finding argues for change to the current bladder cancer staging system.

Lymphadenectomy for Muscle-Invasive Bladder Cancer and Upper Tract Urothelial Cell Carcinoma

There are currently no reported randomized trials that characterize the staging or therapeutic benefit of performing a lymph node dissection in either bladder cancer or upper tract urothelial carcinoma. Several unanswered questions remain in this domain focused on the indications and patient selection for pelvic lymph node dissection, extent of dissection, its impact on outcome, and potential risks. However, the results of observational studies suggest that the burden of metastasis is high in both diseases when muscle invasive and performing a lymphadenectomy can provide prognostic information and yield therapeutic benefit.

A systematic review and meta-analysis on the oncological long-term outcomes after trimodality therapy and radical cystectomy with or without neoadjuvant chemotherapy for muscle-invasive bladder cancer

OBJECTIVE

This study aimed to comprehensively analyze the oncological long-term outcomes of trimodal therapy (TMT) and radical cystectomy (RC) for the treatment of muscle-invasive bladder cancer (BC) with or without neoadjuvant chemotherapy (NAC).

PATIENTS AND METHODS

A systematic search was conducted according to the PRISMA guidelines for studies reporting on outcomes after TMT and RC. A total of 57 studies including 30,293 patients were included. The 10-year overall survival (OS), disease-specific survival (DSS), and recurrence-free survival (RFS) rates for TMT and RC were assessed.

RESULTS

The mean 10-year OS was 30.9% for TMT and 35.1% for RC (P = 0.32). The mean 10-year DSS was 50.9% for TMT and 57.8% for RC (P = 0.26). NAC was administered before therapy to 453 (13.3%) of 3,402 patients treated with TMT and 812 (3.0%) of 27,867 patients treated with RC (P<0.001). Complete response (CR) was achieved in 1,545 (75.3%) of 2,051 evaluable patients treated with TMT. A 5-year OS, DSS, and RFS after CR were 66.9%, 78.3%, and 52.5%, respectively. Downstaging after transurethral bladder tumor resection or NAC to stage ≤pT1 at RC was reported in 2,416 (29.1%) of 8,311 patients. NAC significantly increased the rate of pT0 from 20.2% to 34.3% (P = 0.007) in cT2 and from 3.8% to 23.9% (P<0.001) in cT3-4. A 5-year OS, DSS, and RFS in downstaged patients (≤pT1) at RC were 75.7%, 88.3%, and 75.8%, respectively.

CONCLUSION

In this analysis, the survival outcomes of patients after TMT and RC for MIBC were comparable. Patients who experienced downstaging after NAC and RC exhibited improved survival compared to patients treated with RC only. Best survival outcomes after TMT are associated with CR to this approach.

The anatomical limits and oncological benefit of lymphadenectomy in muscle invasive bladder cancer

BACKGROUND

Lymphadenectomy is part of standard treatment for muscle invasive bladder cancer. The objective of this review is to provide an up-to-date review on the available scientific evidence in this field.

ACQUISITION OF EVIDENCE

We conducted a literature review in PubMed of relevant articles up to the present (2016). We found a systematic review published in 2014 that included the comparative studies published up to that year, and we updated the review with new relevant publications since that date.

SYNTHESIS OF THE EVIDENCE

The number of lymph nodes is not the best indicator for determining the quality of the lymphadenectomy given that the number can vary depending on numerous factors that depend not only on the surgeon but also on the patient and on the pathologist. The definition of standard anatomical territories and a meticulous extraction of the lymph nodes in these territories are more reproducible than the numbers of nodes removed. The optimal extension of lymphadenectomy is a topic of debate. The evidence published to date indicates that any extension of lymphadenectomy is better than not performing it, although it appears that limited lymphadenectomy is insufficient for the oncological control of the disease and that superextended lymphadenectomy provides no oncological benefit versus extended lymphadenectomy.

CONCLUSIONS

Despite a certain amount of controversy in terms of the optimal extension of lymphadenectomy, performing lymphadenectomy in all cases appears to be recommendable according to the available evidence. Extended lymphadenectomy provides greater oncological benefit than more limited dissections, while more extensive lymphadenectomies are not recommended.

Curative Treatment for Muscle Invasive Bladder Cancer in Elderly Patients: A Systematic Review

CONTEXT

The incidence of muscle invasive bladder cancer (MIBC) increases with age. With increased life expectancy the number of elderly MIBC patients is expected to increase. Existing guidelines on management of MIBC do not preclude curative treatments for elderly patients. However, it is necessary to assess the risks and benefits of a treatment to avoid overtreatment that results in decreased health-related quality of life without prolonging survival.

OBJECTIVE

To report on overall survival (OS), cancer specific survival (CSS), and morbidity after curative treatment in elderly patients, defined as age >70 yr, with nonmetastatic MIBC and to compare this with the outcome of younger MIBC patients.

EVIDENCE ACQUISITION

A systematic review was performed using Medline, PubMed, and Embase databases. Articles were included if they addressed one of the three research questions: Only articles including >100 patients and with a clear age-stratification were included.

EVIDENCE SYNTHESIS

Forty-two articles were retrieved for review. No article directly addressed the use of geriatric assessment. OS and CSS worsen significantly with age both after radical cystectomy and radiotherapy regimens. While POM significantly increases with age, morbidity seems comparable between younger and older patients.

CONCLUSIONS

Although a proportion of elderly patients with MIBC will benefit from curative treatment, we observed worse OS, CSS, and POM with age. The impact of age on late morbidity is less clear. Prospective studies evaluating geriatric assessments are critically needed to optimize MIBC management in the elderly.

PATIENT SUMMARY

We performed a systematic review to evaluate the outcome and complication rate in elderly patients with muscle invasive bladder cancer. We observed that overall survival and cancer specific survival significantly decrease and perioperative mortality significantly increases with age. The impact of age on late morbidity is less clear. There is a need for geriatric assessments to select those patients that will benefit from curative treatment.

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.

The treatment of muscle-invasive bladder cancer in geriatric patients

PURPOSE OF REVIEW

Bladder cancer is an age-related cancer and because of aging population, an increase of patients with muscle-invasive bladder cancer (MIBC) seems inevitable. Decisions regarding the treatment of geriatric patients with MIBC are complex and require a multidisciplinary approach.

RECENT FINDINGS

In addition to a specific urological oncology evaluation, a general geriatric evaluation is of great importance for all geriatric patients with MIBC. Standard of care in appropriate geriatric MIBC patients is radical cystectomy with urinary diversion and neoadjuvant platinum-based combination chemotherapy. There is evidence that adjuvant chemotherapy after surgery brings a benefit, but these data are less clear. An alternative to radical cystectomy, especially in elderly patients with concomitant disease, can be trimodal therapy, whereas the equality of this approach remains to be proven.

SUMMARY

Treatment decisions should not be based on the patient's chronological age alone, but rather on overall performance status, quality of life considerations, social performance, and patient preferences. On this account, patients should not be denied a potentially life-saving intervention just because they are elderly. The hope of personalized medicine and targeted therapy with less side-effects and complications may soon become a reality.

Extraperitoneal versus transperitoneal laparoscopic radical cystectomy for selected elderly bladder cancer patients: a single center experience

OBJECTIVE

This study reports the initial experience of extraperitoneal laparoscopic radical cystectomy (ELRC) and compared with transperitoneal laparoscopic radical cystectomy (TLRC) in the treatment of selected elderly bladder cancer patients.

PATIENTS AND METHODS

A total of forty male bladder cancer patients who underwent ELRC (n=19) or TLRC (n=21) with ureterocutaneostomy were investigated. Demographic parameters, perioperative variables, oncological outcomes and follow-up data were retrospectively analyzed.

RESULTS

A significantly shorter time to exsufflation (1.5±0.7 vs 2.1±1.1 d; p=0.026) and liquid intake (1.8±0.9 vs 2.8±1.9 d; p=0.035) were observed in the ELRC group compared with the TLRC group. The incidence of postoperative ileus in the ELRC group was lower than the TLRC group (0 vs 9.5%). However, the difference had no statistical significance (p>0.05). The removed lymph node number in the ELRC group was significantly lower than the TLRC group (p<0.001). No significant differences were observed between the two groups in the overall and cancer-free survival rates (p>0.05).

CONCLUSIONS

ELRC seems to be a safe and feasible surgical strategy for the selected elderly bladder cancer patients with ≤T2 disease. The surgical and oncological efficacy of the ELRC is similar to that of the TLRC, but with faster intestinal function recovery. Further studies with a large series including different urinary diversions are needed to confirm our results and to better evaluate the benefit of ELRC in bladder cancer patients.

Perioperative Outcomes, Health Care Costs, and Survival After Robotic-assisted Versus Open Radical Cystectomy: A National Comparative Effectiveness Study

BACKGROUND

Radical cystectomy is the gold-standard management for muscle-invasive bladder cancer, and there is debate concerning the comparative effectiveness of robotic-assisted (RARC) versus open radical cystectomy (ORC).

OBJECTIVE

To compare utilization, perioperative, cost, and survival outcomes of RARC versus ORC.

DESIGN, SETTING, AND PARTICIPANTS

We identified bladder urothelial carcinoma treated with RARC (n=439) or ORC (n=7308) during 2002-2012 using the Surveillance, Epidemiology, and End Results Program-Medicare linked data.

INTERVENTION

Comparison of RARC versus ORC.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We used propensity score matching to compare perioperative and survival outcomes, including lymph node yield, perioperative complications, and healthcare costs.

RESULTS AND LIMITATIONS

Utilization of RARC increased from 0.7% of radical cystectomies in 2002 to 18.5% in 2012 (p<0.001). Women comprised 13.9% versus 18.1% (p=0.007) of RARC versus ORC, respectively. RARC was associated with greater lymph node yield with 41.5% versus 34.9% having ≥10 lymph nodes removed (relative risk 1.1, 95% confidence interval [CI] 1.01-1.22, p=0.03) and shorter mean length of hospitalization at 10.1 (± standard deviation 7.1) d versus 11.2 (± 8.6) d (p=0.004). While inpatient costs were similar, RARC was associated with increased home healthcare utilization (relative risk 1.14, 95% CI 1.04-1.26, p=0.009) and higher 30-d (p<0.01) and 90-d (p<0.01) costs. With a median follow-up of 44 mo (interquartile range 16-78), overall survival (hazard ratio 0.88, 95% CI 0.74-1.05) and cancer-specific survival (hazard ratio 0.91, 95% CI 0.66-1.26) were similar.

CONCLUSIONS

RARC provides equivalent perioperative and intermediate term outcomes to ORC. Additional long-term and randomized studies are needed for continued comparative effectiveness assessment of RARC versus ORC.

PATIENT SUMMARY

Our population-based US study demonstrates that robotic-assisted radical cystectomy has similar perioperative and survival outcomes albeit at higher costs.

Double-negative feedback loop between long non-coding RNA TUG1 and miR-145 promotes epithelial to mesenchymal transition and radioresistance in human bladder cancer cells

LncRNAs have a critical role in the regulation of cellular processes such as cancer progression and metastasis. In the present study, we confirmed that TUG1 was overexpressed in bladder cancer tissues and established cell lines. Knockdown of TUG1 inhibited bladder cancer cell metastasis both in vitro and in vivo. Furthermore, we found that TUG1 promoted cancer cell invasion and radioresistance through inducing epithelial-to-mesenchymal transition (EMT). Interestingly, TUG1 decreased the expression of miR-145 and there was a reciprocal repression between TUG1 and miR-145 in an Argonaute2-dependent manner. ZEB2 was identified as a down-stream target of miR-145 and TUG1 exerted its function through the miR-145/ZEB2 axis. In summary, our data indicated that blocking TUG1 function may be an effective anti-cancer therapy.