A Phase II Study of the Central European Society of Anticancer-Drug Research (CESAR) Group: Results of an Open-Label Study of Gemcitabine plus Cisplatin with or without Concomitant or Sequential Gefitinib in Patients with Advanced or Metastatic Transitional Cell Carcinoma of the Urothelium

Landscape of targeted therapies for advanced urothelial carcinoma

Bladder cancer (BC) is the tenth most common malignancy globally. Urothelial carcinoma (UC) is a major type of BC, and advanced UC (aUC) is associated with poor clinical outcomes and limited survival rates. Current options for aUC treatment mainly include chemotherapy and immunotherapy. These options have moderate efficacy and modest impact on overall survival and thus highlight the need for novel therapeutic approaches. aUC patients harbor a high tumor mutation burden and abundant molecular alterations, which are the basis for targeted therapies. Erdafitinib is currently the only Food and Drug Administration (FDA)-approved targeted therapy for aUC. Many potential targeted therapeutics aiming at other molecular alterations are under investigation. This review summarizes the current understanding of molecular alterations associated with aUC targeted therapy. It also comprehensively discusses the related interventions for treatment in clinical research and the potential of using novel targeted drugs in combination therapy.

Small-molecule nanoprodrug with high drug loading and EGFR, PI3K/AKT dual-inhibiting properties for bladder cancer treatment

Bladder cancer (BCa) is one of the most common malignancies worldwide. Although multiple efforts have been made, the 5-year survival rate of patients with BCa remains unchanged in recent years. Overexpression of the epidermal growth factor receptor (EGFR) is found in ≈74% of BCa tissue specimens; however, current EGFR-based targeted therapies show little benefit for BCa patients, as the EGFR downstream pathways appear to be circumvented by other receptor tyrosine kinases (RTKs). In this study, two natural products are identified, namely triptolide (TPL) and hesperidin (HSP), that target and inhibit the EGFR and its downstream PI3K/AKT pathway in BCa. To synergistically combine triptolide and hesperidin, a succinic acid linker was employed to conjugate them and formed an amphiphilic TPL-HSP EGFR-targeting prodrug (THE), which further self-assembled to generate nanoparticles (THE NPs). These NPs allowed the EGFR-targeted delivery of the triptolide and hesperidin, and simultaneous inhibition of the EGFR and PI3K/AKT both in vitro and in vivo. This study provides a promising EGFR-targeted delivery approach with the dual inhibition of the EGFR and PI3K/AKT, while also exhibiting a high drug loading and low toxicity. Our formulation may be a suitable option to deliver natural products for BCa treatment by EGFR-targeted therapy.

Epigenetic Priming and Development of New Combination Therapy Approaches

Muscle-invasive urothelial carcinoma of the bladder (MIBC) has been treated with cisplatin-based chemotherapy for over 30 years. With the advent of immune checkpoint inhibitors, antibody drug conjugates and FGFR3 inhibitors new therapeutic options have been approved for patients with urothelial carcinoma (UC) and are still under investigation regarding association between patients' response and recently defined molecular subtypes. Unfortunately, similar to chemotherapy, only a fraction of UC patients responds to these new treatment approaches. Thus, either further new efficacious therapeutic options for treatment of individual subtypes or new approaches to overcome treatment resistance and to increase patients' response to standard of care treatment are needed.Epigenetic modifications of DNA and chromatin are known to mediate cellular plasticity or treatment resistance, and the responsible epigenetic regulators are frequently mutated or aberrantly expressed in UC. Thus, these enzymes provide targets for novel drug combination therapies to "episensitize" toward approved standard therapies by epigenetic priming. In general, these epigenetic regulators comprise writers and erasers like DNA methyltransferases and DNA demethylases (for DNA methylation), histone methyltransferases and histone demethylases (for histone methylation), as well as acetyl transferases and histone deacetylases (for histone and nonhistone acetylation). Such modifications, e.g., acetyl groups, are recognized by further epigenetic reader proteins, e.g., like the bromodomain and extra-terminal domain (BET) family proteins that often interact in multi-protein complexes and finally regulate chromatin conformation and transcriptional activity.Concurringly, epigenetic regulators target a plethora of cellular functions. Their pharmaceutical inhibitors often inhibit enzymatic activity of more than one isoenzyme or may have further noncanonical cytotoxic effects. Thus, analysis of their functions in UC pathogenesis as well as of the antineoplastic capacity of corresponding inhibitors alone or in combination with other approved drugs should follow a multidimensional approach. Here, we present our standard approach to analyze cellular effects of new epigenetic inhibitors on UC cells alone to define their potency and to conclude on putative reasonable combination therapy partners. We further describe our approach to identify efficacious synergistic combination therapies (e.g., with cisplatin or PARP inhibitors) that may have reduced normal toxicity through dose reduction, which can then be further analyzed in animal experiments. This approach may also serve as prototype for the preclinical evaluation of other epigenetic treatment approaches.

Molecularly Targeted Therapy towards Genetic Alterations in Advanced Bladder Cancer

Despite the introduction of immune checkpoint inhibitors and antibody-drug conjugates to the management of advanced urothelial carcinoma, the disease is generally incurable. The increasing incorporation of next-generation sequencing of tumor tissue into the characterization of bladder cancer has led to a better understanding of the somatic genetic aberrations potentially involved in its pathogenesis. Genetic alterations have been observed in kinases, such as FGFRs, ErbBs, PI3K/Akt/mTOR, and Ras-MAPK, and genetic alterations in critical cellular processes, such as chromatin remodeling, cell cycle regulation, and DNA damage repair. However, activating mutations or fusions of FGFR2 and FGFR3 remains the only validated therapeutically actionable alteration, with erdafitinib as the only targeted agent currently approved for this group. Bladder cancer is characterized by genomic heterogeneity and a high tumor mutation burden. This review highlights the potential relevance of aberrations and discusses the current status of targeted therapies directed at them.

Proteomics as a Complementary Technique to Characterize Bladder Cancer

Simple Summary

Although immunohistochemistry is a routine technique in clinics, and genomics has been rapidly incorporated, proteomics is a step behind. This general situation is also the norm in bladder cancer research. This review shows the contributions of proteomics to the molecular classification of bladder cancer, and to the study of histopathology due to tissue insults caused by tumors. Furthermore, the importance of proteomics for understanding the cellular and molecular changes as a consequence of the therapy of bladder cancer cannot be neglected.

Abstract

Bladder cancer (BC) is the most common tumor of the urinary tract and is conventionally classified as either non-muscle invasive or muscle invasive. In addition, histological variants exist, as organized by the WHO-2016 classification. However, innovations in next-generation sequencing have led to molecular classifications of BC. These innovations have also allowed for the tracing of major tumorigenic pathways and, therefore, are positioned as strong supporters of precision medicine. In parallel, immunohistochemistry is still the clinical reference to discriminate histological layers and to stage BC. Key contributions have been made to enlarge the panel of protein immunomarkers. Moreover, the analysis of proteins in liquid biopsy has also provided potential markers. Notwithstanding, their clinical adoption is still low, with very few approved tests. In this context, mass spectrometry-based proteomics has remained a step behind; hence, we aimed to develop them in the community. Herein, the authors introduce the epidemiology and the conventional classifications to review the molecular classification of BC, highlighting the contributions of proteomics. Then, the advances in mass spectrometry techniques focusing on maintaining the integrity of the biological structures are presented, a milestone for the emergence of histoproteomics. Within this field, the review then discusses selected proteins for the comprehension of the pathophysiological mechanisms of BC. Finally, because there is still insufficient knowledge, this review considers proteomics as an important source for the development of BC therapies.

Emerging agents for the treatment of metastatic urothelial cancer

Over the past few decades, platinum-based combination chemotherapy (PBCC) has been the preferred initial therapy for metastatic urothelial cancer (mUC). However, despite a response rate of approximately 50%, a small proportion of patients with distant metastases may be cured by cisplatin-based combination chemotherapy (CBCC). In addition, up to 50% of patients are not eligible for CBCC due to age or comorbidities. Furthermore, adverse effects from PBCC are a major concern. The emergence of check-point inhibitors (CPIs), particularly those with antibodies directed against programmed cell death 1 protein (PD-1) or its ligand (PD-L1), advanced the treatment of mUC. Avelumab switch-maintenance therapy is recommended in patients with locally advanced or mUC who did not progress on initial PBCC. With the recent advances in tumor molecular biology and the discovery of actionable therapeutic targets, the clinical application of targeted therapy is now being explored for mUC. Erdafitinib, a tyrosine kinase inhibitor of FGFR1-4, has shown positive outcomes in patients with advanced UC with FGFR alterations. Another recent technological development is antibody-drug conjugates (ADCs), which are complex molecules composed of an antibody linked to a biologically active cytotoxic drug (payload) that targets and kills tumor cells while sparing healthy cells. Enfortumab vedotin, a monoclonal antibody targeting nectin-4 conjugated to monomethyl auristatin E, has demonstrated clinically significant efficacy in patients who do not respond to both cytotoxic chemotherapy and CPIs. In this review, we describe switch-maintenance therapies using CPI, various targeted agents, and ADCs that have been investigated for mUC treatment.

Novel Tyrosine Kinase Targets in Urothelial Carcinoma

Urothelial carcinoma represents one of the most prevalent types of cancer worldwide, and its incidence is expected to grow. Although the treatment of the advanced disease was based on chemotherapy for decades, the developments of different therapies, such as immune checkpoint inhibitors, antibody drug conjugates and tyrosine kinase inhibitors, are revolutionizing the therapeutic landscape of this tumor. This development coincides with the increasing knowledge of the pathogenesis and genetic alterations in urothelial carcinoma, from the non-muscle invasive setting to the metastatic one. The purpose of this article is to provide a comprehensive review of the different tyrosine kinase targets and their roles in the therapeutic scene of urothelial carcinoma.

Salvage systemic therapy for metastatic urothelial carcinoma: an unmet clinical need

INTRODUCTION

Metastatic urothelial carcinoma (mUC) remains a fatal malignancy, despite the recent addition of immune check point inhibitors (ICIs), an FGFR inhibitor and an antibody-drug conjugate (ADC) to the therapeutic armamentarium. The survival rates are particularly dismal after first-line treatment failure, entailing an urgent need for more effective therapies. Advances in understanding biomarkers and identifying targetable molecules have broadened the pathways under investigation in mUC.

AREAS COVERED

This review summarizes mUC salvage therapy options, including chemotherapy, ICI, and novel promising agents, including targeted therapies, ADCs, cytotoxic agents and vaccines. For the literature review, a PubMed search and relevant data presented at international conferences were used.

EXPERT OPINION

The approval of ICIs, FGFR inhibitor erdafitinib and ADC enfortumab vedotin in the salvage setting has transformed the mUC landscape. Yet there are additional promising agents currently under study. Toxicities are observed with ADCs and FGFR inhibitors, but appear manageable in most patients. The molecular heterogeneity and complex tumor biology are challenging barriers for progress in the therapy of mUC. Advances in molecular profiling, defining validated predictive markers, rational combinations of agents and therapeutically actionable targets will help develop personalized compounds with higher efficacy and less toxicity with hopes to improve outcomes for mUC.

Clinical evidence for the first-line treatment of advanced urothelial carcinoma: Current paradigms and emerging treatment options

BACKGROUND

Patients with advanced urothelial carcinoma (UC) have poor outcomes, with 5-year survival rates of <5% for those with metastatic, stage IV disease. We have reviewed current treatment paradigms and emerging treatment options for these patients.

METHODS

The websites of seven national or international organizations were searched for metastatic UC treatment guidelines. Systematic literature reviews were conducted to identify evidence from randomized controlled trials (RCTs) of chemotherapy for patients with previously untreated, unresectable, stage IV UC. Searches included congress databases and articles published between 1990 and 2018. In order to align with the latest treatment paradigms in first-line advanced UC, a focused literature search was conducted to identify evidence supporting immuno-oncology (IO) agents.

RESULTS

For advanced UC, guidelines universally recommend cisplatin-based chemotherapy as first-line treatment for eligible patients and carboplatin-based regimens for those unfit to receive cisplatin. Despite the evaluation of a number of different cytotoxic regimens over the years, including triplet combinations, survival outcomes have not improved markedly with chemotherapy. Median overall survival with standard of care chemotherapy is ~13 months. Based on the results of single-arm, phase II studies, recent treatment guidelines have included atezolizumab (anti-PD-L1) and pembrolizumab (anti-PD-1) as first-line options for cisplatin-ineligible patients whose tumors express high levels of PD-L1. However, emerging evidence from RCTs of IO agents, including both cisplatin-eligible and cisplatin-ineligible patients, suggest that survival times exceeding 20 months are possible.

CONCLUSIONS

After having reached a plateau with chemotherapy, the treatment landscape for advanced UC is evolving. Survival outcomes for patients with advanced UC are improving with treatment modalities involving IO agents.

Efficacy and Safety of Chemotherapy Regimens in Advanced or Metastatic Bladder and Urothelial Carcinomas: An Updated Network Meta-Analysis

Background: Gemcitabine plus cisplatin (GC) and methotrexate, vinblastine, adriamycin, and cisplatin (MVAC) have been the first-line treatments for advanced or metastatic urothelial carcinoma (AMUC). However, their effects are unsatisfactory, and more drugs and regimens still need to be explored.

Objective: We aimed to comprehensively compare all possible regimens with GC or MVAC in randomized controlled trials (RCTs) by network meta-analysis.

Methods: We searched the PubMed, Embase, and Cochrane databases for RCTs that evaluated regimens compared to GC or MVAC on AMUC patients. The major outcomes were progression-free survival (PFS), overall survival (OS), and objective response rate (ORR). A network meta-analysis was used to assess the effectiveness and safety of the included treatment regimens, and the regimens were then clustered by the average linkage method.

Results: A total of 19 trials that assessed 3,363 AMUC patients were included. For PFS, paclitaxel plus GC (PGC) was significantly superior to GC (log hazard ratio (HR): −0.16; 95% confidence interval (CI): −0.32, 0.00) with a moderate level of reliability. However, there was no significant difference between PGC and MVAC (log HR: −0.03; 95% CI: −0.27, 0.20). For OS, PGC was significantly superior to GC (log HR:−0.17; 95% CI: −0.33, −0.00) with a moderate reliability level but not significantly different from MVAC (log HR: −0.10; 95% CI: −0.35, 0.15). Analysis of ORR showed that PGC was superior to MVAC (log odds ratio (OR): 0.59; 95% CI: 0.02, 1.16) with a low reliability level and GC (log OR: 0.41; 95% CI: 0.12, 0.71) with a moderate reliability level. In the cluster results, PGC and sorafenib plus GC (GCS) exhibited relative advantages in efficiency, followed by MVAC and apatorsen plus GC (GCA); however, PGC, gemcitabine plus carboplatin (GP), and MVAC had more serious side effects.

Conclusions: In our analysis, PGC was superior to MVAC and GC in only the ORR results and superior to GC in the OS and PFS results but was not significantly different from MVAC. More individualized therapies with targeted drugs need to be studied.

Targeted therapies in urothelial bladder cancer: a disappointing past preceding a bright future?

Bladder cancer (BC) is the most frequent cancer affecting the urinary tract. With the growing era of targeted therapies around the 2000s, many trials evaluated the efficacy of targeted therapy in advanced BC. However, no approval was given yet to any form of targeted therapy when it comes to BC. The aim of this paper was to report the most pivotal trials that evaluated different families of targeted therapy in the treatment of BC, according to their biomarkers (FGFR3, EGFR, HER2, VEGF and PI3K/AKT/mTOR). The ongoing trials testing targeted therapies in advanced BC were then summarized. Finally, the different immunotherapies approved for this disease and their potential combination with targeted therapy were addressed.

Epigenetic Treatment Options in Urothelial Carcinoma

Mutations, dysregulation, and dysbalance of epigenetic regulators are especially frequent in urothelial carcinoma (UC) compared to other malignancies. Accordingly, targeting epigenetic regulators may provide a window of opportunity particularly in anticancer therapy of UC. In general, these epigenetic regulators comprise DNA methyltransferases and DNA demethylases (for DNA methylation), histone methyltransferases, and histone demethylases (for histone methylation) as well as acetyl transferases and histone deacetylases (for histone and non-histone acetylation).As epigenetic regulators target a plethora of cellular functions and available inhibitors often inhibit enzymatic activity of more than one isoenzyme or may have further off-target effects, analysis of their functions in UC pathogenesis as well as of the antineoplastic capacity of according inhibitors should follow a multidimensional approach.Here, we present our standard approach for the analysis of the cellular and molecular functions of individual HDAC enzymes, their suitability as treatment targets and for the evaluation of isoenzyme-specific HDAC inhibitors regarding their antineoplastic efficacy. This approach may also serve as prototype for the preclinical evaluation of other epigenetic treatment approaches.

Effectiveness of capecitabine with or without docetaxel therapy for the treatment of patients with advanced urothelial carcinoma: a single-institution experience

PURPOSE

The purpose of this study was to evaluate the effectiveness and toxicity of capecitabine (C) chemotherapy regimen with or without (w/o) docetaxel (D) in patients with advanced urothelial carcinoma (UC).

RESULTS

Clinical benefit rate were similar in two arms (C arm vs DC arm: 38.9% vs 45.5%, p = 0.411). There were two cases achieved partial response in DC arm. In C arm, the median PFS was 3.0 months (95% CI 2.5-3.5 months) and median OS was 11.3 months (95% CI 8.6-14.1 months). In DC arm, the median PFS was 2.2 months (95% CI 1.7-2.7 months) and median OS was 18 months (95% CI 6.8-29.9 months). Adverse events were mostly acceptable, including myelosuppession, hand-foot syndrome and mucositis. Anemia and leukopenia was found more in the DC arm than in the C arm.

MATERIALS AND METHODS

This is a one-center, observational, retrospective study. From April 2009 to March 2015, a total of 29 patients with metastatic UC were included in the study. Survivals, response rates and toxicities were collected retrospectively.

CONCLUSIONS

The result showed the activity and toxicity of C w/o D. As DC treatment did not reveal better outcome, C or D single-agent might be an option in platinum-failed patients with advanced urothelial carcinoma. Further clinical trials are warranted.

Spectrum of genomic alterations in FGFR3: current appraisal of the potential role of FGFR3 in advanced urothelial carcinoma

Molecular analysis has identified subsets of urothelial carcinoma (UC) expressing distinct genetic signatures. Genomic alterations in the oncogenic fibroblast growth factor receptor 3 (FGFR3) pathway are among the most well described in UC and have led to extensive and ongoing investigation of FGFR3-targeted therapies in this disease, although no new drugs have yet been approved. Given the unmet need for effective treatments in advanced and metastatic UC, a better understanding of the known molecular alterations of FGFR3 and of the previous and ongoing clinical investigations of this promising target in UC deserves attention. The objective of the present review is to describe the landscape of alterations and biology of FGFR3 in UC, comprehensively summarize the current state of UC clinical trials of FGFR3 inhibitors, and discuss future therapeutic applications. Using the Pubmed and Clinicaltrials.gov databases, articles describing the spectrum and biological activity of FGFR3 genomic alterations and trials of FGFR3 inhibitors in UC were identified. Search terms included 'FGFR3 genomic alterations' and 'urothelial cancer' or 'bladder cancer'. Genomic alterations, including translocations and activating mutations, are increasingly described in advanced and metastatic UC. The majority of clinical trials have been performed in unselected populations; however, recent studies have reported encouraging preliminary data. We argue that routine use of molecular genomic tumour analysis in UC may inform selection of patients for appropriate trials and we further investigate the potential of FGFR3 as a meaningful clinical target for this difficult disease.

Platinum-based drugs: past, present and future

Platinum-based drugs cisplatin, carboplatin and oxaliplatin are widely used in the therapy of human neoplasms. Their clinical success is, however, limited due to severe side effects and intrinsic or acquired resistance to the treatment. Much effort has been put into the development of new platinum anticancer complexes, but none of them has reached worldwide clinical application so far. Nedaplatin, lobaplatin and heptaplatin received only regional approval. Some new platinum complexes and platinum drug formulations are undergoing clinical trials. Here, we review the main classes of new platinum drug candidates, such as sterically hindered complexes, monofunctional platinum drugs, complexes with biologically active ligands, trans-configured and polynuclear platinum complexes, platinum(IV) prodrugs and platinum-based drug delivery systems. For each class of compounds, a detailed overview of the mechanism of action is given, the cytotoxicity is compared to that of the clinically used platinum drugs, and the clinical perspectives are discussed. A critical analysis of lessons to be learned is presented. Finally, a general outlook regarding future directions in the field of new platinum drugs is given.

Ten Years of Complete Remission of Pulmonary Metastasis after Post-Cystectomy Palliative Cisplatin-Gemcitabine Chemotherapy with Gefitinib for Muscle Invasive Bladder Cancer: A Case Report

Muscle-invasive bladder cancer (MIBC) is considered one of the most lethal malignancies with high metastatic potential. Usually, metastatic bladder cancer carries worse prognosis with a median survival rate of approximately 6 months, which can be prolonged for up to 14 months with palliative systemic chemotherapy. We present the case of a 61-year-old male patient diagnosed with localized MIBC 10 years ago. He underwent nerve-sparing radical cystectomy with ileal neobladder, but developed pulmonary metastatic disease 7 months postoperatively. Six cycles of gemcitabine/cisplatin combination chemotherapy with an addition of gefitinib as daily oral medication were administered within a randomized phase II clinical trial; this resulted in complete remission of the pulmonary metastases. Until now, the patient is still on gefitinib daily without any side effects. Although, the addition of gefitinib to standard systemic chemotherapy has not been shown to improve the survival in metastatic urothelial cancer, this case represents a very pleasant albeit uncommon long-term outcome.