High-Content Drug Discovery Targeting Molecular Bladder Cancer Subtypes.

Molecular subtypes of muscle-invasive bladder cancer (MIBC) display differential survival and drug sensitivities in clinical trials. To date, they have not been used as a paradigm for phenotypic drug discovery. This study aimed to discover novel subtype-stratified therapy approaches based on high-content screening (HCS) drug discovery. Transcriptome expression data of CCLE and BLA-40 cell lines were used for molecular subtype assignment in basal, luminal, and mesenchymal-like cell lines. Two independent HCSs, using focused compound libraries, were conducted to identify subtype-specific drug leads. We correlated lead drug sensitivity data with functional genomics, regulon analysis, and in-vitro drug response-based enrichment analysis. The basal MIBC subtype displayed sensitivity to HDAC and CHK inhibitors, while the luminal subtype was sensitive to MDM2 inhibitors. The mesenchymal-like cell lines were exclusively sensitive to the ITGAV inhibitor SB273005. The role of integrins within this mesenchymal-like MIBC subtype was confirmed via its regulon activity and gene essentiality based on CRISPR-Cas9 knock-out data. Patients with high ITGAV expression showed a significant decrease in the median overall survival. Phenotypic high-content drug screens based on bladder cancer cell lines provide rationales for novel stratified therapeutic approaches as a framework for further prospective validation in clinical trials.

T1 Substaging of Nonmuscle Invasive Bladder Cancer is Associated with bacillus Calmette-Guérin Failure and Improves Patient Stratification at Diagnosis.

PURPOSE: Currently, markers are lacking that can identify patients with high risk nonmuscle invasive bladder cancer who will fail bacillus Calmette-Guérin treatment. Therefore, we evaluated the prognostic value of T1 substaging in patients with primary high risk nonmuscle invasive bladder cancer. MATERIALS AND METHODS: Patients with primary high risk nonmuscle invasive bladder cancer who received ≥5 bacillus Calmette-Guérin induction instillations were included. All tumors were centrally reviewed, which included T1 substaging (microinvasion vs extensive invasion of the lamina propria). T1 patients were stratified into high risk or highest risk subgroups according to major urology guidelines. Primary end point was bacillus Calmette-Guérin failure, defined as development of a high grade recurrence. Secondary end points were high grade recurrence-free survival, defined as time from primary diagnosis to biopsy-proven high grade recurrence and progression-free survival. Time-to-event analyses were used to predict survival. RESULTS: A total of 264 patients with high risk nonmuscle invasive bladder cancer had tumor invasion of the lamina propria, of which 73% were classified as extensive invasion and 27% as microinvasion. Median followup was 68 months (IQR 43-98) and bacillus Calmette-Guérin failure was more common among patients with extensive vs microinvasive tumors (41% vs 21%, p=0.002). The 3-year high grade recurrence-free survival (defined as bacillus Calmette-Guerin failure) for patients with extensive vs microinvasive tumors was 64% vs 83% (p=0.004). In multivariate analysis, T1 substaging was an independent predictor of high grade recurrence-free survival (HR 3.2, p=0.005) and progression-free survival (HR 3.0, p=0.009). Patients with highest risk/microinvasive disease have an improved progression-free survival as compared to highest risk/T1e disease (p.adj=0.038). CONCLUSIONS: T1 substaging provides important prognostic information on patients with primary high risk nonmuscle invasive bladder cancer treated with bacillus Calmette-Guérin. The risk of bacillus Calmette-Guérin failure is higher in extensive vs microinvasive tumors. Substaging of T1 high risk nonmuscle invasive bladder cancer has the potential to guide treatment decisions on bacillus Calmette-Guérin vs alternative strategies at diagnosis.

Improving Anti-PD-1/PD-L1 Therapy for Localized Bladder Cancer.

In high-risk non-muscle invasive bladder cancer (HR-NMIBC), patient outcome is negatively affected by lack of response to Bacillus-Calmette Guérin (BCG) treatment. Lack of response to cisplatin-based neoadjuvant chemotherapy and cisplatin ineligibility reduces successful treatment outcomes in muscle-invasive bladder cancer (MIBC) patients. The effectiveness of PD-1/PD-L1 immune checkpoint inhibitors (ICI) in metastatic disease has stimulated its evaluation as a treatment option in HR-NMIBC and MIBC patients. However, the observed responses, immune-related adverse events and high costs associated with ICI have provided impetus for the development of methods to improve patient stratification, enhance anti-tumorigenic effects and reduce toxicity. Here, we review the challenges and opportunities offered by PD-1/PD-L1 inhibition in HR-NMIBC and MIBC. We highlight the gaps in the field that need to be addressed to improve patient outcome including biomarkers for response stratification and potentially synergistic combination therapy regimens with PD-1/PD-L1 blockade.

Clinical Decision Making in Surveillance of Non-Muscle-Invasive Bladder Cancer: The Evolving Roles of Urinary Cytology and Molecular Markers.

Cystoscopy and urine cytology are the gold-standard tests for detection of recurrent disease during follow-up in patients with a history of non-muscle-invasive bladder cancer (NMIBC). High associated costs, as well as side effects, have driven the desire for inexpensive, noninvasive, accurate, and easy-to-use urine markers to detect bladder cancer recurrence. While many urine markers have been developed, very few have been clinically implemented. In this article, we discuss the requirements for development and validation of urine markers and the factors that hamper their clinical implementation. We also review current surveillance guidelines for NMIBC and provide an overview of approved urine markers for the detection and surveillance of NMIBC.

Molecular biomarkers of progression in non-muscle-invasive bladder cancer - beyond conventional risk stratification.

The global incidence of bladder cancer is more than half a million diagnoses each year. Bladder cancer can be categorized into non-muscle-invasive bladder cancer (NMIBC), which accounts for ~75% of diagnoses, and muscle-invasive bladder cancer (MIBC). Up to 45% of patients with NMIBC develop disease progression to MIBC, which is associated with a poor outcome, highlighting a clinical need to identify these patients. Current risk stratification has a prognostic value, but relies solely on clinicopathological parameters that might not fully capture the complexity of disease progression. Molecular research has led to identification of multiple crucial players involved in NMIBC progression. Identified biomarkers of progression are related to cell cycle, MAPK pathways, apoptosis, tumour microenvironment, chromatin stability and DNA-damage response. However, none of these biomarkers has been prospectively validated. Reported gene signatures of progression do not improve NMIBC risk stratification. Molecular subtypes of NMIBC have improved our understanding of NMIBC progression, but these subtypes are currently unsuitable for clinical implementation owing to a lack of prospective validation, limited predictive value as a result of intratumour subtype heterogeneity, technical challenges, costs and turnaround time. Future steps include the development of consensus molecular NMIBC subtypes that might improve conventional clinicopathological risk stratification. Prospective implementation studies of biomarkers and the design of biomarker-guided clinical trials are required for the integration of molecular biomarkers into clinical practice.

Characterization of Fibroblast Growth Factor Receptor Alterations and Activation in Patients with High-Risk Non-Muscle Invasive Bladder Cancer.

PURPOSE: The GARNER study investigated fibroblast growth factor receptor (FGFR) alteration (ALT) frequency and the clinical outcome relationship with Bacillus Calmette-Guérin (BCG) treatment in high-risk non-muscle invasive bladder cancer (HR-NMIBC). An FGFR predictive response signature (FGFR-PRS) was discovered that identifies patients with an activated FGFR pathway who could potentially benefit from FGFR-targeted therapy beyond those who are FGFR ALT (+). EXPERIMENTAL DESIGN: Pre-treatment tumor samples and clinical data were analyzed from 582 BCG-treated HR-NMIBC patients. FGFR-PRS was discovered using a separate BC dataset and applied to the GARNER and other BC cohorts. FGFR-PRS was also applied to in vitro data from UC cell lines treated with FGFR-active agents. RESULTS: 31% of pre-treatment GARNER HR-NMIBC tumors were FGFR ALT (+) but this was not significantly associated with BCG response. For the subset of patients with paired pre- and post-BCG treatment samples, nearly one-third pre-treatment ALT (+) patients were ALT (-) post-treatment. FGFR-PRS identified patients with an activated FGFR pathway and identified approximately 2-fold additional patients compared to ALT status alone, and this increase was similar across tumor stage. A positive relationship between tumor growth inhibition and FGFR-PRS score was shown in BC in vitro models treated with FGFR-active agents. CONCLUSIONS: These data provide support for FGFR-targeted therapy use in FGFR ALT (+) HR-NMIBC and describe tumors with shared FGFR pathway-activated biology that are FGFR ALT (-) but FGFR-PRS (+). The latter suggests a broader potential patient population for FGFR-targeted therapy, which will require subsequent validation in patients treated with FGFR-targeted therapy.

A Genomic Urine Assay for Surveillance of Patients with Bladder Cancer Treated with Radiotherapy.

Background: Patients with muscle-invasive bladder cancer (MIBC) who receive radiotherapy with curative intent are followed by imaging, cystoscopy, and urine cytology. However, interpretation of cytology and cystoscopy is hampered by the impact of ionizing radiation on cells. Objective: To assess the diagnostic performance of a genomic urine assay to detect urinary tract recurrences in patients with MIBC treated by (chemo)radiation. Design setting and participants: Patients with nonmetastatic MIBC who underwent (chemo)radiation with curative intent from 2016 to 2020 were prospectively included. Follow-up consisted of cystoscopy and upper tract imaging. Prior to cystoscopy, a urine sample was analyzed to assess mutations in the genes FGFR3, HRAS, and TERT and methylation of OTX1, TWIST1, and ONECUT2. The treating physician was blinded for the assay result. Outcome measurements and statistical analysis: The primary endpoint was a urinary tract recurrence. Cross-sectional sensitivity, specificity, and negative predictive value (NPV) were analyzed using a previously developed logistic regression model for the detection of bladder cancer with this assay. The secondary endpoint was the risk of a future urinary tract recurrence following a positive test and negative cystoscopy/imaging, using a time-dependent Cox proportional hazard analysis. Results and limitations: A total of 143 patients were included, and 503 urine samples were analyzed. The median study duration was 20 mo (interquartile range [IQR] 10-33), and the median time to a recurrence was 16 mo (IQR 12-26). In 27 patients, 32 urinary tract recurrences were diagnosed, including three upper tract tumors. Of 32 recurrences, 18 (56%) had a concomitant urine test available. The diagnostic model had an area under the curve of 0.80 (95% confidence interval [CI] 0.69-0.90) with corresponding sensitivity, specificity, and NPV of 78 (95% CI 52-94), 77% (95% CI 73-81), and 99% (95% CI 97-100). When taking into account the anticipatory effect of the test, 28/32 (88%) recurrences were detected. A Cox regression analysis showed a hazard ratio of 14.8 for the development of a future recurrence (p < 0.001). A major limitation was the lack of a concomitant urine test result in 14/32 (44%) recurrences. Conclusions: A genomic urine assay detected urinary tract recurrences after (chemo)radiation in patients with MIBC, and a positive test was strongly associated with future recurrences. Although validation in a large cohort is warranted, the test has the potential to limit frequent cystoscopies. Patient summary: Radiotherapy is a bladder-sparing treatment in patients with bladder cancer. After treatment, these patients undergo visual inspection of the bladder by cystoscopy to detect possible recurrences. However, interpretation of cystoscopy is difficult due to the effects of radiation on the bladder lining. Hence, we analyzed the diagnostic value of a molecular urine test to detect recurrent disease in bladder cancer patients treated by radiotherapy, and we showed that the urine test has the potential to limit the number of cystoscopies.

A Molecular Urine Assay to Detect Recurrences During Surveillance of High-Risk Non-Muscle Invasive Bladder Cancer.

BACKGROUND: High-risk non-muscle invasive bladder cancer (HR-NMIBC) patients require long-term surveillance with cystoscopies, cytology and upper tract imaging. Previously, we developed a genomic urine assay for surveillance of HR-NMIBC patients with high sensitivity and anticipatory value. OBJECTIVE: We aimed to validate the performance of the assay in an unselected prospectively collected cohort of HR-NMIBC patients under surveillance. METHODS: We included patients from five centers and collected urine sample pairs (evening and morning urines) prior to cystoscopy. Mutation status (FGFR3/TERT) and methylation status (OTX1) was analyzed on DNA from voided urine specimens. A test was considered positive if≥1 alteration was detected in at least one urine sample. The primary endpoint was tumor recurrence. Sensitivity and specificity were determined. A generalized mixed effects model was used to adjust for within-patient correlation. Cox proportional hazard analyses with time-dependent covariates assessed the anticipatory effect of the urine assay. RESULTS: In total, 204 patients and 736 sample pairs were collected. Sixty-three recurrences were diagnosed for which we had concomitant assay results. On cross-sectional analyses, the assay detected 75% (95% CI 62.1% -84.7%) of recurrences, with a specificity of 70% (95% CI 66.4% -73.5%). Furthermore, mixed effects model analyses revealed OTX1 (p = 0.005) and TERT (p = 0.004) as significant predictors for disease recurrence. Median follow-up was 25.3 months (IQR 18.6-30.7). Twenty-nine tumors were diagnosed without concomitant urine samples, which included recurrences detected after urine collection ended. Longitudinal analyses showed that a positive urine assay predicted a recurrence over time (HR 3.5, p < 0.001). Furthermore, a recurrence during the study period was also a predictor for developing future recurrences (HR 2.1, p < 0.001). CONCLUSIONS: This study validates the performance of a previously developed urine assay in an unselected cohort of HR-NMIBC patients under surveillance. With a robust sensitivity/specificity and a strong anticipatory effect, this assay proves a useful adjunct ready for evaluation in a future randomized controlled trial.

Sewage surveillance system using urological wastewater: Key to COVID-19 monitoring?

Since December 2019, the emergence of a new Severe Acute Respiratory Syndrome- coronavirus (SARS-CoV-2) has led to a global coronavirus pandemic disease (COVID-19), with devastating consequences for all healthcare worldwide, including urological care. COVID-19 has led to concern among urological healthcare workers about viral presence, detection and routes of transmission during routine clinical practice. The potential presence of (active) virus in bodily fluids of COVID-19 patients remains a continuing topic of debate. Therefore, we highlight viral detection methods and review the presence of SARS-CoV-2 in urine, feces, and semen. Finally, we discuss how excretion of virus particles through urological bodily fluids might be pivotal to epidemiologic monitoring and control of the disease.

Non-muscle-invasive bladder cancer molecular subtypes predict differential response to intravesical Bacillus Calmette-Guérin.

The recommended treatment for patients with high-risk non-muscle-invasive bladder cancer (HR-NMIBC) is tumor resection followed by adjuvant Bacillus Calmette-Guérin (BCG) bladder instillations. However, only 50% of patients benefit from this therapy. If progression to advanced disease occurs, then patients must undergo a radical cystectomy with risks of substantial morbidity and poor clinical outcome. Identifying tumors unlikely to respond to BCG can translate into alternative treatments, such as early radical cystectomy, targeted therapies, or immunotherapies. Here, we conducted molecular profiling of 132 patients with BCG-naive HR-NMIBC and 44 patients with recurrences after BCG (34 matched), which uncovered three distinct BCG response subtypes (BRS1, 2 and BRS3). Patients with BRS3 tumors had a reduced recurrence-free and progression-free survival compared with BRS1/2. BRS3 tumors expressed high epithelial-to-mesenchymal transition and basal markers and had an immunosuppressive profile, which was confirmed with spatial proteomics. Tumors that recurred after BCG were enriched for BRS3. BRS stratification was validated in a second cohort of 151 BCG-naive patients with HR-NMIBC, and the molecular subtypes outperformed guideline-recommended risk stratification based on clinicopathological variables. For clinical application, we confirmed that a commercially approved assay was able to predict BRS3 tumors with an area under the curve of 0.87. These BCG response subtypes will allow for improved identification of patients with HR-NMIBC at the highest risk of progression and have the potential to be used to select more appropriate treatments for patients unlikely to respond to BCG.

Long-term efficacy of hyperthermic intravesical chemotherapy for BCG-unresponsive non-muscle invasive bladder cancer.

BACKGROUND: The recommended treatment for patients with Bacillus Calmette-Guérin (BCG) unresponsive non-muscle invasive bladder cancer (NMIBC) is radical cystectomy (RC). However, many patients refuse, or are unfit for RC. Therefore, alternative bladder-sparing treatment modalities are needed for BCG-unresponsive NMIBC. In this study we sought to assess the long-term efficacy of hyperthermic intravesical chemotherapy (HIVEC) as alternative to radical cystectomy in BCG-unresponsive non-muscle invasive bladder cancer patients. METHODS AND MATERIALS: Retrospectively collected data from 56 patients with BCG-unresponsive NMIBC who received ≥5 HIVEC instillations between October 2014 and March 2020 was analyzed. All patients met the BCG-unresponsive criteria according to the current EAU guideline on NMIBC 2020. Patients were followed-up with cystoscopy and/or bladder biopsies, urine cytology and annually CT-urography. The Primary outcome was the high grade (HG) recurrence-free survival (RFS), defined as the time from the first HIVEC instillation until histologically confirmed intravesical recurrence or last follow-up. The Kaplan Meier method was used to estimate survival outcomes. Secondary outcomes were: complete response rate (CR), adverse events (AE), assessed by the Common Terminology Criteria for Adverse Events v5.0 (CTCAE) and tumor progression to muscle invasive disease or distant metastases. RESULTS: The median follow-up was 32.2 months (IQR 13.7-44.8). The 1- and 2-year HG-RFS was 53% (SE:6.8) and 35% (SE:6.9), respectively. The CR for patients with CIS was 70% (21/30) at 6 months. Overall, 80% of the population developed an AE, only 1 was classified as CTCAE ≥3. Limitation of this study was the small sample size. CONCLUSION: HIVEC resulted in a 2-year HG-RFS of 35% for BCG-unresponsive NMIBC patients without severe side-effects and therefore HIVEC seems to be an alternative treatment option for patients who refuse or are unfit for RC.

Role of Bladder Cancer Metabolic Reprogramming in the Effectiveness of Immunotherapy.

Metabolic reprogramming (MR) is an upregulation of biosynthetic and bioenergetic pathways to satisfy increased energy and metabolic building block demands of tumors. This includes glycolytic activity, which deprives the tumor microenvironment (TME) of nutrients while increasing extracellular lactic acid. This inhibits cytotoxic immune activity either via direct metabolic competition between cancer cells and cytotoxic host cells or by the production of immune-suppressive metabolites such as lactate or kynurenine. Since immunotherapy is a major treatment option in patients with metastatic urothelial carcinoma (UC), MR may have profound implications for the success of such therapy. Here, we review how MR impacts host immune response to UC and the impact on immunotherapy response (including checkpoint inhibitors, adaptive T cell therapy, T cell activation, antigen presentation, and changes in the tumor microenvironment). Articles were identified by literature searches on the keywords or references to "UC" and "MR". We found several promising therapeutic approaches emerging from preclinical models that can circumvent suppressive MR effects on the immune system. A select summary of active clinical trials is provided with examples of possible options to enhance the effectiveness of immunotherapy. In conclusion, the literature suggests manipulating the MR is feasible and may improve immunotherapy effectiveness in UC.

Molecular Biomarkers of Response to PD-1/ PD-L1 Immune Checkpoint Blockade in Advanced Bladder Cancer.

BACKGROUND: The activity of PD-1/PD-L1 inhibitors in the treatment of advanced bladder cancer (BC) is promising for many patients. However, a subset of patients do not benefit from treatment, thus leading to an effort to better identify predictive molecular biomarkers of response. OBJECTIVE: To conduct a systematic review of the literature on predictive molecular biomarkers associated with response to PD-1 and PD-L1 inhibitors in advanced bladder cancer, defined as locally-advanced, unresectable, or metastatic (mBC) disease. METHODS: A search of the literature was performed using Embase (1947 - January 2019), Medline (1946 - January 2019), and EBM Reviews for Cochrane Central Register of Controlled Trials (as of December 2018). Studies examining the association of molecular biomarkers with clinical outcome in BC treated with PD-1 or PD-L1 monotherapy were included. Outcomes of interest were overall survival (OS), cancer-specific survival (CSS), progression-free survival (PFS), duration of response, and objective response rate (ORR). RESULTS: Using the study search criteria, 899 unique abstract citations were found, of which 834 did not meet the eligibility criteria. Full text of the remaining 65 citations were screened, and 50 studies excluded, including 18 review articles. Eight additional studies from the bibliography of the review papers were included, making a total of 23 studies. Five PD-1 / PD-L1 antibodies have been tested in BC immunohistochemistry (IHC). These studies used different expression scoring criteria and generally had poor ability to discriminate likelihood for response. Overall, the data suggests CD8+ T cell infiltration is necessary to mediate an antitumor immune response, but other immune cell populations, such as neutrophils may suppress T cell-mediated immunity and efficacy of PD-1/PD-L1 blockade. An IFNγ signature is a promising predictor, but there needs to be consensus on the optimal gene panel composition, and prospective validation. Tumor mutation burden (TMB) is a promising predictor in six studies reporting on 1200 patients, but there is not a consensus on the optimal definition of "high TMB". Detection of T cell receptor (TCR) clonal expansion has only been conducted in small studies and so its predictive value remains inconclusive. Epithelial-mesenchymal transformation (EMT) and transforming growth factor ß (TGFß) are associated with poor prognosis and possibly intrinsic resistance to PD-1/PD-L1 checkpoint blockade, but more work needs to be done to build upon and confirm the initial findings. CONCLUSIONS: Currently no molecular biomarker is sufficiently mature for routine clinical use, while some candidates, or a combination show great promise and need further study.

Systematic Review: Characteristics and Preclinical Uses of Bladder Cancer Cell Lines.

BACKGROUND: Bladder cancer (BC) cell lines are indispensable in basic and preclinical research. Currently, an up-to-date and comprehensive overview of available BC cell lines is not available. OBJECTIVE: To provide an overview and resources on the origin, pathological and molecular characteristics of commonly used human, murine and canine BC cell lines. METHODS: A PubMed search was performed for relevant articles published between 1980 and 2017 according to the following MeSH terms: cell line; cell line, tumor; urinary bladder neoplasms; carcinoma, transitional cell. The Cellosaurus database was searched, using the term "bladder" and/or "urothelial carcinoma". We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. RESULTS: We provide information on 157 human, murine and canine BC cell lines. 103 human BC cell lines have molecular data available, of which 69 have been profiled by at least one "omic" technology. We outline how these cell lines are currently being used for in vitro and in vivo experimental models. These results allow direct comparison of BC cell lines to patient samples, providing information needed to make informed decisions on the most genomically appropriate cell line to answer research questions. Furthermore, we show that cross-contamination remains an issue and describe guidelines for prevention. CONCLUSIONS: In the BC field, multiple human, murine and canine BC cell lines have been developed and many have become indispensable for in vitro and in vivo research. High-throughput -omic technologies have dramatically increased the amount of molecular data on these cell lines. We synthesized a comprehensive overview of these data as a resource for the BC scientific community.