Future directions and targeted therapies in bladder cancer

Anti-tumoral effect of beta-blockers on prostate and bladder cancer cells via mitogen-activated protein kinase pathways

The incidence of prostate cancer in the world is increasing every year. Death caused by prostate cancer is increased by 13% in men between 1980 and 2005. It is the second leading cause of cancer death in men after lung cancer. Bladder cancer is the second most common of urological malignancies. Most of the bladder cancers are treated with transurethral resection. Even great efforts have been made in the treatment of bladder cancer over the past years, it still remains as a major health problem. New therapeutic approaches are required to prevent the development and metastasis of these diseases. Experimental and clinical studies have shown potential beneficial effects of co-administration of beta-adrenergic receptor antagonists (beta-blockers) during cancer therapy. This study aimed to investigate the anti-tumor activity of beta-blockers on prostate and bladder cancer. Prostate and bladder cancer cell lines were cultured and treated with beta-blocker (propranolol). Then, protein levels and activity of apoptotic pathway mediators and mitogen-activated protein kinase (MAPK) pathway mediators were analyzed by ELISA. Propranolol treatment elevated the activity of caspase-3 and expression of bax, Wee1, GADD153 and apoptosis-inducing factor, but decreased bcl-2 which is an antiapoptotic protein. Propranolol treatment also inhibited ERK and JNK activity. This study showed that propranolol will help to inhibit prostate and bladder cancer by activating apoptotic pathway and by inhibiting MAPK pathway. This is the first study investigating the apoptotic effect of propranolol via MAPK on prostate and bladder cancer.

Therapeutically actionable PAK4 is amplified, overexpressed, and involved in bladder cancer progression

Muscle-invasive bladder carcinomas (MIBCs) are aggressive genitourinary malignancies. Metastatic urothelial carcinoma of the bladder is generally incurable by current chemotherapy and leads to early mortality. Recent studies have identified molecular subtypes of MIBCs with different sensitivities to frontline therapy, suggesting tumor heterogeneity. We have performed multi-omic profiling of the kinome in bladder cancer patients with the goal of identify therapeutic targets. Our analyses revealed amplification, overexpression, and elevated kinase activity of P21 (RAC1) activated kinase 4 (PAK4) in a subset of Bladder cancer (BLCA). Using bladder cancer cells, we confirmed the role of PAK4 in BLCA cell proliferation and invasion. Furthermore, we observed that a PAK4 inhibitor was effective in curtailing growth of BLCA cells. Transcriptomic analyses identified elevated expression of another kinase, protein tyrosine kinase 6 (PTK6), upon treatment with a PAK4 inhibitor and RNA interference of PAK4. Treatment with a combination of kinase inhibitors (vandetanib and dasatinib) showed enhanced sensitivity compared with either drug alone. Thus, PAK4 may be therapeutically actionable for a subset of MIBC patients with amplified and/or overexpressed PAK4 in their tumors. Our results also indicate that combined inhibition of PAK4 and PTK6 may overcome resistance to PAK4. These observations warrant clinical investigations with selected BLCA patients.

Epidemiology and unmet needs of bladder cancer in Italy: a critical review

Bladder cancer is one of the most frequent cancers in high-income countries. Information on bladder cancer in Italy is scattered across scientific literature and institutional and educational resources and no attempt has been made yet to organize and summarize this information across various sources of available data. We, therefore, present herein a critical literature review of recent epidemiological and healthcare data, including patients' unmet needs. We undertook a critical review of the scientific and grey literature by exploring several different databases and search browsers. Available official statistics indicate a high burden of bladder cancer in Italy, where this neoplasm has one of the highest incidences worldwide and, in consideration of its relatively high survival, it ranks 4th in cancer prevalence. The limited therapeutic options for muscle-invasive and advanced/metastatic urothelial cancer are one of the major unmet needs for patients with this neoplasm, in Italy and worldwide. Advances in cancer immunotherapy and in understanding molecular biology of bladder cancer are, however, rapidly altering the therapeutic landscape for targeted subgroups of patients with advanced/metastatic disease. Other unmet needs include the low quality of life after radical cystectomy, the lack of widespread clinical pathway schemes to improve and standardize the quality of care and low Italian patients empowerment. Bladder cancer represents a health burden in Italy, with high incidence and prevalence rates, and important unmet needs for patients, including the limited therapeutic options for advanced/metastatic cancers, the low quality of life after radical cystectomy, the lack of widespread clinical pathway schemes, and the low patients empowerment.

Unmet informational and supportive care needs of patients with muscle invasive bladder cancer: A systematic review of the evidence

BACKGROUND

Little is known about the unmet supportive care needs of patients affected by muscle invasive bladder cancer (MIBC). We set out to determine the different domains of unmet supportive care needs for patients affected by MIBC.

LITERATURE SEARCH

A systematic review was conducted according to the PRISMA Statement Guidelines. A sensitive search was performed in electronic databases (DARE, Cochrane, MEDLINE, BNI, PsychINFO, EMBASE and CIHAHL) from the earliest date available to January 2017.

DATA EVALUATION

1405 references were retrieved, 8 articles met the eligibility criteria and were appraised and ranked by strength using the levels of evidence.

SYNTHESIS

Individual unmet needs were classified into the following domains: patient-clinician communication, daily living needs, health system/information needs, practical needs, family-related needs, social needs, psychological needs, physical needs and intimacy needs. Patients reported high unmet needs at diagnosis and into survivorship.

CONCLUSIONS

This review contributes to a greater understanding of the unmet supportive care needs of patients affected by MIBC. Findings reflect a paucity of research, but existing studies indicated needs commonly related to intimacy, informational, physical and psychological needs. Despite the emerging evidence-base, the current within study limitations precludes our understanding about how the needs of patients evolve over time.

Knockdown of fibrous sheath interacting protein 1 expression reduces bladder urothelial carcinoma cell proliferation and induces apoptosis via inhibition of the PI3K/AKT pathway

Background

FSIP1 plays a vital role in tumorigenesis and cancer progression. In bladder cancer, FSIP1 overexpression was associated with poor prognosis of bladder urothelial carcinoma. In this study, we investigated whether FSIP1 is essential in the progression of bladder cancer and the mechanism by which it mediates this effect.

Methods

FSIP1 expression was knocked down in bladder cancer cells using lentiviral-mediated short hairpin RNA (shRNA). FSIP1 expression was detected using Western blotting, immunohistochemistry (IHC), and quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). The effects of FSIP1 knockdown on tumor cells were assessed using colony formation, 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), and flow cytometry (FCM) apoptosis assays in vitro and BALB/c nude mouse xenograft model in vivo.

Results

The findings suggested that FSIP1 protein was highly expressed in bladder cancer cell lines. Knockdown of FSIP1 resulted in reduced tumor cell viability, cell cycle arrest at G₀/G₁ phase and apoptosis of bladder cancer cell lines (P<0.05). Moreover, knockdown of FSIP1 expression suppressed the tumor formation and growth of bladder cancer xenografts (P<0.05). At the gene level, knockdown of FSIP1 expression downregulated the activity of the PI3K/AKT signaling pathway.

Conclusion

This study demonstrated that knockdown of FSIP1 suppressed bladder cancer cell malignant behaviors in vitro and in vivo through the inhibition of the PI3K/AKT signaling pathway, suggesting that targeting FSIP1 could be further evaluated as a potential therapeutic strategy in bladder cancer.

A Comprehensive Review of US FDA-Approved Immune Checkpoint Inhibitors in Urothelial Carcinoma

Few effective treatment options are available for patients with advanced or metastatic urothelial carcinoma (UC) after unsuccessful first-line platinum-based chemotherapy. To date, immune checkpoint inhibitors are novel therapeutic agents for UC treatment. From May 2016 to May 2017, five anti-PD-1/PD-L1 monoclonal antibodies received accelerated or regular approval from the US Food and Drug Administration (FDA) for the treatment of patients with locally advanced or metastatic UC. The present comprehensive review presents the background information of these five US FDA-approved anticancer agents to provide a basic but concise understanding of these agents for advanced studies. We summarize their immune checkpoint mechanisms, clinical efficacy, recommended usage protocols, adverse events, and the limitations of the PD-L1 biomarker assays.

Emerging role of Hippo signalling pathway in bladder cancer

Bladder cancer (BC) is one of the most common cancers worldwide with a high progression rate and poor prognosis. The Hippo signalling pathway is a conserved pathway that plays a crucial role in cellular proliferation, differentiation and apoptosis. Furthermore, dysregulation and/or malfunction of the Hippo pathway is common in various human tumours, including BC. In this review, an overview of the Hippo pathway in BC and other cancers is presented. We focus on recent data regarding the Hippo pathway, its network and the regulation of the downstream co-effectors YAP1/TAZ. The core components of the Hippo pathway, which induce BC stemness acquisition, metastasis and chemoresistance, will be emphasized. Additional research on the Hippo pathway will advance our understanding of the mechanism of BC as well as the development and progression of other cancers and may be exploited therapeutically.

Contemporary update on neoadjuvant therapy for bladder cancer

Administration of neoadjuvant chemotherapy preceding radical cystectomy in patients with bladder cancer remains a matter of debate. Results of prospective, randomized studies have demonstrated an overall absolute survival benefit of 5% at 5 years, provided cisplatin-based combination regimens are used. Owing to the perception of a modest survival benefit, the medical community has been slow to adopt the use of neoadjuvant chemotherapy. Other reasons for the underuse of neoadjuvant chemotherapy range from patient ineligibility to fear of delaying potentially curative surgery in nonresponders. Instead, several institutions have adopted an individualized, risk-adapted approach, in which the decision to administer chemotherapy is based on clinical stage and patient comorbidity profile. The development of new cytotoxic and targeted therapies, in particular immune checkpoint inhibitors, warrants well-designed prospective studies to test their efficacy alone or in combination in the neoadjuvant setting. Moving forward, genomic characterization of muscle-invasive bladder cancer could offer information that aids clinicians in selecting the appropriate chemotherapy regimen. Following neoadjuvant therapy, every effort should be made to ensure optimal surgery, as surgical margins and the number of removed lymph nodes are prognostic factors; thus, radical cystectomy and a meticulous extended pelvic lymph node dissection should be performed by expert surgeons.

Nomogram-based Prediction of Overall Survival in Patients with Metastatic Urothelial Carcinoma Receiving First-line Platinum-based Chemotherapy: Retrospective International Study of Invasive/Advanced Cancer of the Urothelium (RISC)

BACKGROUND

The available prognostic models for overall survival (OS) in patients with metastatic urothelial carcinoma (UC) have been derived from clinical trial populations of cisplatin-treated patients.

OBJECTIVE

To develop a new model based on real-world patients.

DESIGN, SETTING, AND PARTICIPANTS

Individual patient-level data from 29 centers were collected, including metastatic UC and first-line cisplatin- or carboplatin-based chemotherapy administered between January 2006 and January 2011.

INTERVENTION

First-line, platinum-based, combination chemotherapy.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The population was randomly split into a development and a validation cohort. Generalized boosted regression modelling was used to screen out irrelevant variables and address multivariable analyses. Two nomograms were built to estimate OS probability, the first based on baseline factors and platinum agent, the second incorporating objective response (OR). The performance of the above nomograms and that of other available models was assessed. We plotted decision curves to evaluate the clinical usefulness of the two nomograms.

RESULTS AND LIMITATIONS

A total of 1020 patients were analyzed (development: 687, validation: 333). In a platinum-stratified Cox model, significant variables for OS were performance status (p<0.001), white blood cell count (p=0.013), body mass index (p=0.003), ethnicity (p=0.012), lung, liver, or bone metastases (p<0.001), and prior perioperative chemotherapy (p=0.012). The c-index was 0.660. The distribution of the nomogram scores was associated with OR (p<0.001), and incorporating OR into the model further improved the c-index in the validation cohort (0.670).

CONCLUSIONS

We developed and validated two nomograms for OS to be used before and after completion of first-line chemotherapy for metastatic UC.

PATIENT SUMMARY

We proposed two models for estimating overall survival of patients with metastatic urothelial carcinoma receiving first-line, platinum-based chemotherapy. These nomograms have been developed on real-world patients who were treated outside of clinical trials and may be used irrespective of the chemotherapeutic platinum agent used.

Molecular targets in urothelial cancer: detection, treatment, and animal models of bladder cancer

Bladder cancer remains one of the most expensive cancers to treat in the United States due to the length of required treatment and degree of recurrence. In order to treat bladder cancer more effectively, targeted therapies are being investigated. In order to use targeted therapy in a patient, it is important to provide a genetic background of the patient. Recent advances in genome sequencing, as well as transcriptome analysis, have identified major pathway components altered in bladder cancer. The purpose of this review is to provide a broad background on bladder cancer, including its causes, diagnosis, stages, treatments, animal models, as well as signaling pathways in bladder cancer. The major focus is given to the PI3K/AKT pathway, p53/pRb signaling pathways, and the histone modification machinery. Because several promising immunological therapies are also emerging in the treatment of bladder cancer, focus is also given on general activation of the immune system for the treatment of bladder cancer.

Systemic therapy in muscle-invasive and metastatic bladder cancer: current trends and future promises

Bladder urothelial cancers remain an important urologic cancer with limited treatment options in the locally advanced and metastatic setting. While neoadjuvant chemotherapy for locally advanced muscle-invasive cancers has shown overall survival benefit, clinical uptake in practice have lagged behind. Controversies surrounding adjuvant chemotherapy use are also ongoing. Systemic therapies for metastatic bladder cancer have largely used platinum-based therapies without effective standard second-line therapy options for those who fail, although vinflunine is approved in Europe as a second-line therapy based on a Phase III trial, and most recently, atezolizumab, a checkpoint inhibitor, was approved by the US FDA. Given increasing recognition of mutational signatures expressed in urothelial carcinomas, several promising agents with use of VEGF-targeted therapies, HER2-directed agents and immunotherapies with PD-1/PD-L1 antibodies in various settings are discussed herein.

Invasive Bladder Cancer: Genomic Insights and Therapeutic Promise

Invasive bladder cancer, for which there have been few therapeutic advances in the past 20 years, is a significant medical problem associated with metastatic disease and frequent mortality. Although previous studies had identified many genetic alterations in invasive bladder cancer, recent genome-wide studies have provided a more comprehensive view. Here, we review those recent findings and suggest therapeutic strategies. Bladder cancer has a high mutation rate, exceeded only by lung cancer and melanoma. About 65% of all mutations are due to APOBEC-mediated mutagenesis. There is a high frequency of mutations and/or genomic amplification or deletion events that affect many of the canonical signaling pathways involved in cancer development: cell cycle, receptor tyrosine kinase, RAS, and PI-3-kinase/mTOR. In addition, mutations in chromatin-modifying genes are unusually frequent in comparison with other cancers, and mutation or amplification of transcription factors is also common. Expression clustering analyses organize bladder cancers into four principal groups, which can be characterized as luminal, immune undifferentiated, luminal immune, and basal. The four groups show markedly different expression patterns for urothelial differentiation (keratins and uroplakins) and immunity genes (CD274 and CTLA4), among others. These observations suggest numerous therapeutic opportunities, including kinase inhibitors and antibody therapies for genes in the canonical signaling pathways, histone deacetylase inhibitors and novel molecules for chromatin gene mutations, and immune therapies, which should be targeted to specific patients based on genomic profiling of their cancers.

Association of epithelial-mesenchymal transition and nuclear cofilin with advanced urothelial cancer

Tumor epithelial cells undergo a morphologic shift through the process of EMT with characteristic loss of cell polarity, conferring invasive and metastatic properties during cancer progression. Signaling by transforming growth factor-β mediates EMT programming and its phenotypic reversal to mesenchymal-epithelial transition. The role of EMT in bladder cancer progression to advanced disease is poorly understood. In this study, we conducted a retrospective analysis of the EMT landscape and actin cytoskeleton remodeling in a series of human bladder cancer specimens. Immunoreactivity for E-cadherin, N-cadherin, and vimentin protein expression was performed toward establishing an EMT signature in human bladder cancer. Serial sections were assessed for the primary regulator of the actin cytoskeleton remodeling and transforming growth factor-β signaling effector, cofilin. Our results demonstrate that EMT induction in clinical bladder cancer specimens is significantly associated with bladder cancer progression to high-grade, invasive disease. Evaluation of expression and cellular localization of the cytoskeleton regulator cofilin revealed a significant association between overexpression of nuclear cofilin with bladder cancer progression. This study is of translational significance in defining the value of EMT signature and cytoskeletal cofilin as potential tumor markers and targetable platforms for the treatment of invasive bladder cancer.

Vinflunine treatment in patients with metastatic urothelial cancer: A Nordic retrospective multicenter analysis

In 2009, vinflunine was introduced as a second-line treatment to be used after the failure of platinum therapy in patients with metastatic urothelial carcinoma (mUC). The present study investigated the administered vinflunine to patients with mUC in standard clinical practice with the aim of evaluating treatment patterns, response, survival parameters and side-effects. Data were collected retrospectively from the first 100 mUC patients treated with vinflunine at three Nordic cancer centers associated with the Nordic Urothelial Cancer Oncology Group. The overall response rate was 23% and complete response was observed in one patient. The median progression-free survival (mPFS) and median overall survival (mOS) were 2.8 (range, 0.5–34.3) and 6.3 (range, 0.3–39.7) months, respectively. An Eastern Cooperative Oncology Group performance status (ECOG PS) of 2 was present in 20% of the patients, and those patients exhibited significantly shorter mOS (4.1 vs. 7.0 months, P=0.001) and a significantly higher degree of grade 3/4 toxicity (P=0.026) compared with ECOG PS 0–1 patients. Furthermore, patients without visceral metastases had significantly longer mOS than patients with visceral metastases (10.6 vs. 6.0 months, P=0.008). The median number of cycles of vinflunine was 3 (range, 1–28). The current data confirms that vinflunine is an active agent for second-line treatment in an unselected clinical cohort of patients with mUC. ECOG PS and presence of visceral metastases were significant prognostic parameters. In particular, patients with ECOG PS 2 receiving vinflunine had a shorter mOS and a higher frequency of severe toxicity, and, thus, should be treated with caution. Furthermore, the present study observed large inter-individual differences in radiological response and OS, indicating the need for further development of improved patient selection tools to optimize vinflunine treatment in platinum-refractory mUC patients.

An open-label, single-arm, phase 2 study of the Aurora kinase A inhibitor alisertib in patients with advanced urothelial cancer

BACKGROUND

Progress in developing effective salvage therapies for UC is warranted. Alisertib is an orally available, selective inhibitor of the aurora kinase A.

METHODS

A single-group, phase 2 trial was conducted with alisertib 50 mg orally BID for 7 days, with 14d rest until disease progression (PD) (NCT02109328). The primary endpoint (EP) was RECIST 1.1 objective response-rate (ORR, H0 ≤ 5%, H1 ≥ 20%, α = 10% and β = 20%). Eligibility included failure of at least one platinum-based regimen.

RESULTS

From 10/2014 to 04/2015, 22 patients were enrolled (20 evaluable for response), 8 (36.4%) in second-line and 14 (63.6 %) beyond the second-line. Eight (36.4%) had an ECOG-performance status 1-2. Two partial responses (PR, ORR: 9.1%), 7 stable disease (SD) and 11 PD were obtained. Median follow-up was 8.3 months (IQR: 7-10.3), 6-month progression-free survival (PFS) was 13.6% (95%CI: 4.8-39.0). Two SD are still receiving treatment after 11.5 and 6.3 months. Median overall survival (OS) was not reached (6-month OS: 59.1%, 95%CI: 41.7-83.7). Hb < 10 g/dl was significantly associated with shorter PFS and OS multivariably (p = 0.031 and p = 0.033). Tissue of the case with 11.5 month SD harbored a missense mutation of mTOR (E1813D), the nonsense mutation Q527STOP of TSC1, HER3 and TAF1L missense mutations. Grade 3-4 adverse events (AE) were: 40.9% mucositis, 36.4% fatigue, 18.2% neutropenia (13.6% febrile neutropenia). There were 2 treatment-related deaths.

CONCLUSIONS

The study did not meet the primary EP, yet sustained disease control was obtained in about 14% of patients. The incidence of AE and the issue of patient selection are two major concerns.

Muscle-invasive urothelial bladder cancer: an update on systemic therapy

Urothelial carcinoma is a common malignancy that carries a poor prognosis when the disease includes muscle invasion. Metastatic urothelial carcinoma is almost uniformly fatal. The evidence behind treatment options in the neoadjuvant, adjuvant and metastatic settings are discussed in this manuscript, with a focused review of standard and investigational cytotoxic, targeted, and immunotherapy approaches. We have focused especially on neoadjuvant cisplatin-based therapy (supported by level one evidence) and on novel immunotherapy agents such as checkpoint inhibitors, which have shown great promise in early clinical studies.

Second-line single-agent versus doublet chemotherapy as salvage therapy for metastatic urothelial cancer: a systematic review and meta-analysis

BACKGROUND

The efficacy and safety of a combination of chemotherapeutic agent compared with single-agent chemotherapy in the second-line setting of advanced urothelial carcinoma (UC) are unclear. We aimed to study the survival impact of single-agent compared with doublet chemotherapy as second-line chemotherapy of advanced UC.

PATIENTS AND METHODS

Literature was searched for studies including single-agent or doublet chemotherapy in the second-line setting after platinum-based chemotherapy. Random-effects models were used to pool trial-level data according to treatment arm, including median progression-free survival (PFS), overall survival (OS), objective response rate (ORR) probability, and grade 3-4 toxicity. Univariable and multivariable analyses, including sensitivity analyses, were carried out, adjusting for the percent of patients with ECOG performance status ≥1 and hepatic metastases.

RESULTS

Forty-six arms of trials including 1910 patients were selected: 22 arms with single agent (n = 1202) and 24 arms with doublets (n = 708). The pooled ORR with single agents was 14.2% [95% confidence interval (CI) 11.1-17.9] versus 31.9% [95% CI 27.3-36.9] with doublet chemotherapy. Pooled median PFS was 2.69 and 4.05 months, respectively. The pooled median OS was 6.98 and 8.50 months, respectively. Multivariably, the odds ratio for ORR and the pooled median difference of PFS were statistically significant (P < 0.001 and P = 0.002) whereas the median difference in OS was not (P = 0.284). When including single-agent vinflunine or taxanes only, differences were significant only for ORR (P < 0.001) favoring doublet chemotherapy. No statistically significant differences in grade 3-4 toxicity were seen between the two groups.

CONCLUSIONS

Despite significant improvements in ORR and PFS, doublet regimens did not extend OS compared with single agents for the second-line chemotherapy of UC. Prospective trials are necessary to elucidate the role of combination chemotherapy, with or without targeted agents, in the salvage setting. Currently, improvements in this field should be pursued considering single-agent chemotherapy as the foundation for new more active combinations.