Antibody-drug conjugates for urothelial carcinoma

Nectin-4 Expression in Prostatic Adenocarcinoma: An Immunohistochemical Study

BACKGROUND

The Nectin-4 directed antibody drug conjugate enfortumab vedotin (EV) has emerged as frontline systemic therapy in combination with immune checkpoint blockade for urothelial carcinoma (UC), capitalizing on the ubiquitous expression of this protein in UC. There is limited data available regarding expression of Nectin-4 by immunohistochemistry in prostate cancer, but this is of interest as a substantial number of UC patients likely to receive EV have concomitant prostate cancer.

METHODS

Nectin-4 protein expression was evaluated by immunohistochemistry in tissue microarrays encompassing a cohort of 302 prostatic adenocarcinomas spanning Grade Groups 1-5. Intensity of expression was scored from 1 (weak) to 3 (intense staining readily apparent at low magnification). H-scores were calculated by multiplying the percentage of cells staining by the intensity of expression.

RESULTS

Nectin-4 expression was frequently observed in benign prostate tissue (86% of cases, mean H-score of 40, median 20, interquartile range [IQR]: 10-60) and in prostatic adenocarcinoma (91% of cases, mean H-score of 90, median 70, IQR: 20-150). Significant differences in Nectin-4 expression among prostatic adenocarcinoma Grade Groups 1-5 were not observed. Across all prostatic adenocarcinomas evaluated, the mean Nectin-4 H-score of 90 was statistically significantly higher than the mean H-score of 40 observed in benign prostate tissue (p < 0.001). Three of four prostatic ductal adenocarcinomas showed Nectin-4 expression, with a median H-score of 250 (IQR: 152-300).

CONCLUSIONS

Nectin-4 protein expression is common in benign prostate tissue and prostatic adenocarcinoma. These findings provide a rationale for future studies investigating potential activity of EV in prostate cancer.

Immunoproteasome subunits are novel signatures for predicting efficacy of immunotherapy in muscle invasive bladder cancer

BACKGROUND

How to select muscle-invasive bladder cancer (MIBC) patients who are sensitive to immunotherapy is an unmet medical need. This study aimed to explore the role of immunoproteasome subunits as a novel signature for predicting efficacy of immunotherapy in MIBC.

METHODS

The expression profile of immunoproteasome subunits of MIBC and normal tissues was evaluated from data of The Cancer Genome Atlas (TCGA) and of the Chongqing University Cancer Hospital (CQUCH) cohort. Survival analysis and response to immunotherapy was further explored and compared between immunoproteasome subunitshigh and immunoproteasome subunitslow MIBC patients in the TCGA, the CQUCH and the IMvigor210 cohort. The association of the expression of immunoproteasome subunits with immune checkpoint molecules and the tumor immune microenvironment was explored by immunohistochemistry staining and bioinformatic analysis in MIBC of these three cohorts.

RESULTS

The expression of the immunoproteasome subunits PSMB8, PSMB9 and PSMB10 was significantly upregulated in MIBC. MIBC patients with high expression of immunoproteasome subunits, especially high expression of PSMB9, showed a trend of prolonged overall and progression free survival, which was further significantly improved in response to immunotherapy. Bioinformatics and immunohistochemistry staining revealed a positive correlation of the expression of immunoproteasome subunits with the expression of immune checkpoint molecules, with T cell activation and with T cell-mediated cytotoxicity.

CONCLUSIONS

Immunoproteasome subunits, in particular PSMB9, are immune microenvironment-related molecules of MIBC and are promising signatures for survival prediction in response to immunotherapy of MIBC.

Organ-Specific Tumor Response to Enfortumab Vedotin for Metastatic Urothelial Carcinoma: A Multicenter Retrospective Study

INTRODUCTION

To evaluate the organ-specific therapeutic effect of enfortumab vedotin (EV) after chemotherapy and immunotherapy failed for advanced urothelial carcinoma.

MATERIALS METHODS

At 6 institutions between December 2021 and July 2023, we retrospectively analyzed patients with metastatic upper and lower urinary tract cancer who received EV monotherapy after platinum-based chemotherapy and immune checkpoint blockade therapy. Objective response rate (ORR) and organ-specific response rate (OSRR) were evaluated according to the Response Evaluation Criteria in Solid Tumors, version 1.1.

RESULTS

This study analyzed 58 patients with 210 tumor lesions, of which 24% were females and 48% had upper urinary tract cancer. The ORR and disease control rate were 53.5% and 74.1%. Moreover, we found 15 target lesions in the primary site, 7 in local recurrence, 93 in the lymph nodes, 46 in the lung, 29 in the liver, and 20 in the bone, with OSRRs of 40%, 71.4%, 61.1%, 70.6%, 90.9%, and 18.2%, respectively. Over time from baseline, the reduction rate (median) in tumor burden was 50% or more in the lymph node, lung, and liver metastases.

CONCLUSION

The organ-specific tumor response to EV in patients with metastatic urothelial carcinoma was almost favorable. The antitumor activity of EV monotherapy may be less in bone metastasis than in other organ sites. Conversely, EV showed remarkably high efficacy against liver metastasis.

Nectin-4: A promising prognostic marker and therapeutic target in cancer

Nectin cell adhesion protein 4 (Nectin-4), a calcium-independent immunoglobulin-like protein, has garnered significant attention in oncology due to its pronounced overexpression in malignant tumors and absence in healthy adult tissues. Elevated levels of Nectin-4 have been implicated in the pathogenesis of various cancers, including lung, breast, and urothelial carcinomas. Notably, Nectin-4 has emerged as a promising serological marker for these malignancies, facilitating early diagnosis and monitoring of disease progression. The clinical relevance of Nectin-4 is underscored by the Food and Drug Administration's approval of enfortumab vedotin (EV), the first antibody-drug conjugate targeting this protein, for the treatment of urothelial carcinoma. Ongoing clinical trials are expanding the therapeutic applications of EV, highlighting the critical role of Nectin-4 in targeted cancer therapy. Furthermore, novel therapeutic agents targeting Nectin-4 are under investigation, offering potential new avenues for cancer treatment. Despite these advancements, the precise molecular mechanisms by which Nectin-4 influences carcinogenesis and tumor progression remain inadequately understood. Challenges such as therapy-related adverse effects and the development of drug resistance further complicate the clinical management of Nectin-4-associated cancers. This review investigates the molecular functions of Nectin-4, emphasizing its diagnostic and prognostic value in cancer. We also explore the landscape of novel drug discoveries targeting Nectin-4 and provide an overview of current clinical trials aimed at utilizing this marker for therapeutic interventions. By elucidating the multifaceted role of Nectin-4 in malignancies, this article aims to advance our understanding and improve the clinical outcomes for patients with Nectin-4 overexpressing tumors.

New Advances in Metastatic Urothelial Cancer: A Narrative Review on Recent Developments and Future Perspectives

The standard of care for advanced or metastatic urothelial carcinoma (mUC) was historically identified with platinum-based chemotherapy. Thanks to the advances in biological and genetic knowledge and technologies, new therapeutic agents have emerged in this setting recently: the immune checkpoint inhibitors and the fibroblast growth factor receptor inhibitors as the target therapy for patients harboring alterations in the fibroblast growth factor receptor (FGFR) pathway. However, chasing a tumor's tendency to recur and progress, a new class of agents has more recently entered the scene, with promising results. Antibody-drug conjugates (ADCs) are in fact the latest addition, with enfortumab vedotin being the first to receive accelerated approval by the U.S. Food and Drug Administration in December 2019, followed by sacituzumab govitecan. Many other ADCs are still under investigation. ADCs undoubtedly represent the new frontier, with the potential of transforming the management of mUC treatment in the future. Therefore, we reviewed the landscape of mUC treatment options, giving an insight into the molecular basis and mechanisms, and evaluating new therapeutic strategies in the perspective of more and more personalized treatments.

Advances in preclinical assessment of therapeutic targets for bladder cancer precision medicine

PURPOSE OF REVIEW

Bladder cancer incidence is on the rise, and until recently, there has been little to no change in treatment regimens over the last 40 years. Hence, it is imperative to work on strategies and approaches to untangle the complexity of intra- and inter-tumour heterogeneity of bladder cancer with the aim of improving patient-specific care and treatment outcomes. The focus of this review is therefore to highlight novel targets, advances, and therapy approaches for bladder cancer patients.

RECENT FINDINGS

The success of combining an antibody-drug conjugate (ADC) with immunotherapy has been recently hailed as a game changer in treating bladder cancer patients. Hence, interest in other ADCs as a treatment option is also rife. Furthermore, strategies to overcome chemoresistance to standard therapy have been described recently. In addition, other studies showed that targeting genomic alterations (e.g. mutations in FGFR3 , DNA damage repair genes and loss of the Y chromosome) could also be helpful as prognostic and treatment stratification biomarkers. The use of single-cell RNA sequencing approaches has allowed better characterisation of the tumour microenvironment and subsequent identification of novel targets. Functional precision medicine could be another avenue to improve and guide personalized treatment options.

SUMMARY

Several novel preclinical targets and treatment options have been described recently. The validation of these advances will lead to the development and implementation of robust personalized treatment regimens for bladder cancer patients.

Durable Response After Combination Therapy With Enfortumab Vedotin and Radiotherapy in Metastatic Urothelial Carcinoma: A Report of Two Cases

Enfortumab vedotin for urothelial carcinoma is a potentially effective anti-tumor drug that can be used in 3rd-line therapy or later, even in relatively advanced stages of the disease. Here, we present two cases of treatment using enfortumab vedotin with subsequent radiotherapy for primary lesions, and long-term disease control was achieved. The first case involved a 78-year-old man previously treated with pembrolizumab following gemcitabine plus carboplatin for lower ureteral carcinoma with multiple lung and lymph node metastases. Six months after the initiation of enfortumab vedotin, the primary tumor and metastases notably shrank. However, the primary tumor regrew, and radiotherapy was initiated along with enfortumab vedotin. The second case involved a 60-year-old man who was initially treated with avelumab following gemcitabine plus cisplatin for bladder cancer with multiple lymph node metastases. After two months of enfortumab vedotin, the primary and metastatic lesions shrunk. However, the primary tumor regrew, and radiotherapy was initiated. In both cases, the primary tumor and metastases recorded long-term shrinkage. The combination of radiotherapy and enfortumab vedotin may be an effective treatment option.

Precision Medicine in Urothelial Carcinoma: Current Markers to Guide Treatment and Promising Future Directions

OPINION STATEMENT

The treatment landscape for urothelial cancer has changed dramatically in the last 10 years, with the approval of several new treatments. At the same time, profiling of individual tumors has become more commonplace with widespread availability of molecular testing and immunohistochemistry. For urothelial cancer, this has led to current guidelines recommending that molecular testing be obtained in the metastatic setting, and that it be considered in the setting of locally advanced disease. Between molecular testing and immunohistochemistry testing of tumors, the only current guideline-directed application of these tests is in the identification of FGFR3 or FGFR2 alterations for use of FGFR inhibitors. While additional recurrent molecular alterations linked to the pathogenesis of urothelial cancer have been identified, the ability to successfully "drug" the pathways association with such alterations remains limited. There has been extensive research into whether expression of particular proteins might inform specific treatment approaches such as the use of PD-L1 testing to guide immune checkpoint blockade. With the integration of antibody-drug conjugates into the treatment armamentarium for urothelial cancer, ongoing research is seeking to determine whether expression of the targets of these therapies, such as Nectin 4, Trop-2, or HER2, could help to guide treatment.

A new era in the treatment of urothelial carcinoma

The advances in targeted therapies, immunotherapy, and the recent emergence of antibody-drug conjugates (ADCs) herald a potential paradigm shift in treating patients with metastatic urothelial cancer. Yet, there are inherent challenges in utilizing these therapies, including the management of treatment-related toxicities. In this special Urologic Oncology: Seminars and Original Investigations issue, we review the latest developments and discuss insights into future research needs.

Temporary Tumor Shrinkage Following Enfortumab Vedotin Therapy for Metastatic Urothelial Carcinoma After Radical Cystectomy With Neoadjuvant Chemotherapy: A Case Report

A 39-year-old Japanese male patient presented with a chief complaint of gross hematuria persistent for two months. However, no relevant findings in the patient's medical and family history were observed. He was diagnosed with muscle-invasive bladder cancer, clinical stage T2bN0M0. After four courses of neoadjuvant chemotherapy with gemcitabine and cisplatin, the tumor size reduced by approximately 30%. The patient underwent robot-assisted radical cystectomy with standard lymph node dissection followed by intracorporeal ileal conduit reconstruction. Histologically, the tumor was diagnosed as a high-grade urothelial carcinoma invading the fatty tissue surrounding the bladder and metastasizing to the lymph nodes, with a pathological stage of ypT3aypN2M0. Four months after surgery, multiple metastases were detected, and treatment with pembrolizumab was initiated immediately. However, the patient did not respond to pembrolizumab. Therefore, a third-line treatment with enfortumab vedotin (EV) was initiated. Thereafter, the metastatic lesion shrank quickly, and the metastatic lesions almost disappeared after two courses of EV administration. Although new metastases were observed at other sites, there has been no regrowth to date. EV-related adverse events were not observed during follow-up. Eighteen months after the surgery, the patient remains alive with multiple metastases. Therefore, the sequence of treatment should be considered to maximize the therapeutic effect of EV, and, consequently, administering EV as early as possible may be important.