Immune checkpoint inhibitors in genitourinary malignancies

The combination of immune checkpoint inhibitors and antibody-drug conjugates in the treatment of urogenital tumors: a review insights from phase 2 and 3 studies

With the high incidence of urogenital tumors worldwide, urinary system tumors are among the top 10 most common tumors in men, with prostate cancer ranking first and bladder cancer fourth. Patients with resistant urogenital tumors often have poor prognosis. In recent years, researchers have discovered numerous specific cancer antigens, which has led to the development of several new anti-cancer drugs. Using protein analysis techniques, researchers developed immune checkpoint inhibitors (ICIs) and antibody-conjugated drugs (ADCs) for the treatment of advanced urogenital tumors. However, tumor resistance often leads to the failure of monotherapy. Therefore, clinical trials of the combination of ICIs and ADCs have been carried out in numerous centers around the world. This article reviewed phase 2 and 3 clinical studies of ICIs, ADCs, and their combination in the treatment of urogenital tumors to highlight safe and effective methods for selecting individualized therapeutic strategies for patients. ICIs activate the immune system, whereas ADCs link monoclonal antibodies to toxins, which can achieve a synergistic effect when the two drugs are combined. This synergistic effect provides multiple advantages for the treatment of urogenital tumors.

The Variations' in Genes Encoding TIM-3 and Its Ligand, Galectin-9, Influence on ccRCC Risk and Prognosis

Renal cell cancer is the most common type of kidney cancer in adults, and clear cell renal cell carcinoma (ccRCC) is the most diagnosed type. T cell immunoglobulin and mucin-domain-containing-3 (TIM-3) belongs to immunological checkpoints that are key regulators of the immune response. One of the known TIM-3 ligands is galectin-9 (LGALS9). A limited number of studies have shown an association between TIM-3 polymorphisms and cancer risk in the Asian population; however, there is no study on the role of LGALS9 polymorphisms in cancer. The present study aimed to analyze the influence of TIM-3 and LGALS9 polymorphisms on susceptibility to ccRCC and patient overall survival (OS), with over ten years of observations. Using TaqMan probes, ARMS-PCR, and RFPL-PCR, we genotyped two TIM-3 single-nucleotide polymorphisms (SNPs): rs1036199 and rs10057302, and four LGALS9 SNPs: rs361497, rs3751093, rs4239242, and rs4794976. We found that the presence of the rs10057302 A allele (AC + AA genotypes) as well as the rs4794976 T allele (GT + TT genotypes) decreased susceptibility to ccRCC by two-fold compared to corresponding homozygotes. A subgroup analysis showed the association of some SNPs with clinical features. Moreover, TIM-3 rs1036199 significantly influenced OS. Our results indicate that variations within TIM-3 and LGALS9 genes are associated with ccRCC risk and OS.

Immunotherapy in Genitourinary Malignancy: Evolution in Revolution or Revolution in Evolution

Immunotherapy, the 5th pillar of cancer care after surgery, radiotherapy, cytotoxic chemotherapy, and precision therapy (molecular targeted therapy), is revolutionizing the standard of care in certain patients with genitourinary malignancies. As modest clinical benefits of IL-2 for metastatic renal cell carcinoma and Bacillus Calmette-Guerin therapy for early-stage bladder cancers in the past years, immune checkpoint inhibitors therapies demonstrate meaningful survival benefit and durable clinical response in renal cell carcinoma, urothelial carcinoma, and some prostate cancer. Despite best efforts, the benefits are limited to a minority of unselected patients due to the complexities of biomarker development. Now come the next hurdles: figuring out which patients best respond to immune checkpoint inhibitors and which patients won't respond to immune checkpoint inhibitors? How best to approach immune checkpoint inhibitors therapies to extend/maximize the treatment response as long as possible? How to overcome therapeutic resistance by specific concurrent immunomodulators or targeted therapy or chemotherapy? The role of immune checkpoint inhibitors in combination or sequencing with chemotherapy or other targeted therapies or other immunomodulating therapeutics in the early disease, neoadjuvant, adjuvant, and metastatic setting is actively under exploration. Ideal strategy for cancer care is to provide not just more time, but more quality time: there remain unmet needs for novel therapies that exploit molecular or genetic pathways to extend survival without compromising health-related quality of life for patients with advanced genitourinary malignancies. Further research is needed to discover new therapeutic strategies, and validate efficacy and effectiveness in real-world settings.

Circular RNAs and Drug Resistance in Genitourinary Cancers: A Literature Review

Simple Summary

Drug resistance to systematic treatment in genitourinary tumors severely aggravated the burden on patients and society. Multiple mechanisms were involved in drug resistance. As typical non-coding RNAs, circRNAs play a critical role in the onset and development of cancers and several studies implied their function in the regulation of drug resistance. Here, we reviewed the investigations of circRNAs’ behavior in drug resistance of genitourinary cancers and summarized the underlying mechanisms. This review emphasized the essential role of circRNAs in drug resistance development and also pointed out the potential topics that need further investigations in the future.

Abstract

In recent years, systematic treatment has made great progress in genitourinary tumors. However, some patients develop resistance to the treatments, resulting in an increase in mortality. Circular RNAs (circRNAs) form a class of non-coding RNAs with high stability and significant clinical relevance. Accumulating evidence indicates that circRNAs play a vital role in cancer development and tumor chemotherapy resistance. This review summarizes the molecular and cellular mechanisms of drug resistance mediated by circRNAs to common drugs used in the treatment of genitourinary tumors. Several circRNAs were identified to regulate the responsiveness to systemic treatments in genitourinary tumors, including chemotherapies such as cisplatin and targeted therapies such as enzalutamide. Canonically, cicrRNAs participate in the competing endogenous RNA (ceRNA) network, or in some cases directly interact with proteins, regulate downstream pathways, and even some circRNAs have the potential to produce proteins or polypeptides. Several cellular mechanisms were involved in circRNA-dependent drug resistance, including autophagy, cancer stem cells, epithelial-mesenchymal transition, and exosomes. The potential clinical prospect of circRNAs in regulating tumor drug resistance was also discussed.

Development of Incidence and Surgical Treatment of Penile Cancer in Germany from 2006 to 2016: Potential Implications for Future Management

BACKGROUND

Penile cancer is a rare disease and surgical treatment often entails a significant impact on quality of life. The aim of this study was to analyze trends in surgical treatment patterns in Germany.

METHODS

We analyzed data from the nationwide German hospital billing database and the German cancer registry from 2006 to 2016. All penile cancer cases with penile surgery or lymph node dissection (LND) were included. We also analyzed the distribution of cases, extent of surgery, and length of hospital stay, stratified for annual caseload. The geographical distribution of centers for 2016 was presented.

RESULTS

During the investigated timespan, tumor incidences increased from 748 to 971 (p = 0.001). We identified 11,353 penile surgery cases, increasing from 886 to 1196 (p < 0.001), and 5173 cases of LND, increasing from 332 to 590 (p < 0.001). Cases of partial amputation increased from 45.8 to 53.8% (p < 0.001), while total amputation remained stable at 11.2%. Caseload in high-volume hospitals increased from 9.0 to 18.8% for penile surgery (p < 0.001) and from 0 to 13.1% for LND (p < 0.001). The increase in LND caseload was caused by an increase in inguinal LND, from 297 to 505 (p < 0.001), with increasing sentinel LND, from 14.2 to 21.9% (p = 0.098). The assessment of geographical distribution of cases in Germany revealed extensive areas without sufficient coverage by experienced centers.

CONCLUSIONS

We saw consistent increases in penile surgery and LND, with a growing number of cases in high-volume hospitals, and, accordingly, an increase in tumor incidence. The increasing use of inguinal LND and organ-preserving surgery reflect the adaptation of current guidelines; however, geographical distribution of experienced centers could be improved.

Basal and Luminal Molecular Subtypes in Naturally-Occurring Canine Urothelial Carcinoma are Associated with Tumor Immune Signatures and Dog Breed

BACKGROUND

Improved therapies are needed for patients with invasive urothelial carcinoma (InvUC). Tailoring treatment to molecular subtypes holds promise, but requires further study, including studies in pre-clinical animal models. Naturally-occurring canine InvUC harbors luminal and basal subtypes, mimicking those observed in humans, and could offer a relevant model for the disease in people.

OBJECTIVE

To further validate the canine InvUC model, clinical and tumor characteristics associated with luminal and basal subtypes in dogs were determined, with comparison to findings from humans.

METHODS

RNA sequencing (RNA-seq) analyses were performed on 56 canine InvUC tissues and bladder mucosa from four normal dogs. Data were aligned to CanFam 3.1, and differentially expressed genes identified. Data were interrogated with panels of genes defining luminal and basal subtypes, immune signatures, and other tumor features. Subject and tumor characteristics, and outcome data were obtained from medical records.

RESULTS

Twenty-nine tumors were classified as luminal and 27 tumors as basal subtype. Basal tumors were strongly associated with immune infiltration (OR 52.22, 95%CI 4.68-582.38, P = 0.001) and cancer progression signatures in RNA-seq analyses, more advanced clinical stage, and earlier onset of distant metastases in exploratory analyses (P = 0.0113). Luminal tumors were strongly associated with breeds at high risk for InvUC (OR 0.06, 95%CI 0.01 -0.37, P = 0.002), non-immune infiltrative signatures, and less advanced clinical stage.

CONCLUSIONS

Dogs with InvUC could provide a valuable model for testing new treatment strategies in the context of molecular subtype and immune status, and the search for germline variants impacting InvUC onset and subtype.

Highlighting recent treatment advances in metastatic prostate cancer: expanding the treatment arsenal

PURPOSE OF REVIEW

Present highlights from recent research examining the treatment of advanced prostate cancer.

RECENT FINDINGS

Although debate remains about the optimal sequencing of docetaxel and novel androgen directed therapies in addition to androgen deprivation therapy (ADT) in the treatment of men with new metastatic prostate cancer, the novel LHRH antagonist relugolix seems poised to become an appealing option in a choice of initial ADT. Novel radioisotopes, genomically selected therapies, and immune therapy combinations show progress in opening up new treatment options for men with castration-resistant prostate cancer.

SUMMARY

Although no clear consensus has emerged, evolving data continue to refine the selection of systemic therapies in treatment naïve metastatic prostate cancer. With potentially less cardiotoxic androgen deprivation therapies, novel radioisotopes, targeted pharmaceuticals, and immune therapy combinations, progress appears to be on the horizon in improving outcomes for men with advanced prostate cancer.

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.

A Systematic Review of the Emerging Role of Immune Checkpoint Inhibitors in Metastatic Castration-resistant Prostate Cancer: Will Combination Strategies Improve Efficacy?

CONTEXT

The role of immune checkpoint inhibition (ICI) in the treatment of prostate cancer (PC) still remains elusive. It has been proposed that combination of ICI with other molecules increases the efficacy of immunotherapy in PC.

OBJECTIVE

To systematically review the literature to assess the potential role of ICI in combination with additional therapies for the management of metastatic castration-resistant PC (mCRPC).

EVIDENCE ACQUISITION

A systematic review using Medline and scientific meeting records was carried out in September 2020 according to the Preferred Reporting Items for Systematic Review and Meta-analyses guidelines. Ongoing trials of immunotherapy with standard mCRPC therapeutics were identified via a systematic search on ClinicalTrials.gov.

EVIDENCE SYNTHESIS

A total of five full-text papers, ten congress abstracts, and 15 trials on ClinicalTrials.gov were identified. Preclinical evidence suggests that combinational approaches might be considered to enhance the efficacy of ICI in PC patients. This led to the design of more than 50 immunotherapy-based clinical trials. The majority of the studies focus on ICI combinations with vaccines, androgen deprivation therapy, chemotherapy, PARP inhibition, radiotherapy, and prostate-specific membrane antigen-guided radioligand therapy. Preliminary analyses reported promising findings for the use of ICI in combination with other anticancer therapies. However, no phase 3 trial has yet reported final results, so no level 1 evidence with long-term outcomes currently supports the combination of ICI with mCRPC therapies.

CONCLUSIONS

Preclinical and clinical trials have demonstrated that combining immunotherapy with standard mCRPC treatment options has the potential to provide a synergistic effect. Nonetheless, a better understanding of the mechanism and of the optimal treatment approach is still needed.

PATIENT SUMMARY

We reviewed the literature on immunotherapy in combination with standard treatments for patients with metastatic castration-resistant prostate cancer (mCRPC). Current evidence supports the hypothesis that immunotherapeutic drugs might be effective in mCRPC if combined with other treatment options. However, results of ongoing trials are still awaited before this novel treatment approach can be implemented in the daily practice.