Bladder sparing landscape for bacillus Calmette-Guérin unresponsive bladder cancer

Identification of New Prognostic Markers and Therapeutic Targets for Non-Muscle Invasive Bladder Cancer: HER2 as a Potential Target Antigen

Bacillus Calmette–Guérin (BCG) is the gold standard adjuvant treatment for non-muscle-invasive bladder cancer (NMIBC). However, given the current global shortage of BCG, new treatments are needed. We evaluated tumor microenvironment markers as potential BCG alternatives for NMIBC treatment. Programmed death-ligand 1, human epidermal growth factor receptor-2 (HER2), programmed cell death-1 (PD1), CD8, and Ki67 levels were measured in treatment-naïve NMIBC and MIBC patients (pTa, pT1, and pT2 stages). Univariate and multivariate Cox proportional hazard models were used to determine the impact of these markers and other clinicopathological factors on survival, recurrence, and progression. EP263, IM142, PD1, and Ki67 levels were the highest in the T2 stage, followed by the T1 and Ta stages. HER2 and IM263 expressions were higher in the T1 and T2 stages than in the Ta stage. In NMIBC, the significant prognostic factors for recurrence-free survival were adjuvant therapy, tumor grade, and HER2 positivity, whereas those for progression-free survival included age, T-stage, and IM263. Age, T-stage, EP263, PD1, CD8, and Ki67 levels were significant factors associated with overall survival. IM263 and HER2 are potential biomarkers for progression and recurrence, respectively. Therefore, we propose HER2 as a potential target antigen for intravesical therapeutics as a BCG alternative.

Checkpoint Inhibition in Bladder Cancer: Clinical Expectations, Current Evidence, and Proposal of Future Strategies Based on a Tumor-Specific Immunobiological Approach

Simple Summary

In contrast with other strategies, immunotherapy is a treatment aimed at empowering the patient’s immune system in order to increase immunity and the response against cancer. Recently, a new class of drugs, immune checkpoint inhibitors, has shown potential in increasing treatment chances for patients with bladder cancers, improving their survival. However, predicting the response to immune checkpoint inhibition is important, since only a group of patients develop a good response. Biomarkers to predict the response to checkpoint inhibition must identify tumors’ and patients’ specific profiles. This study reviews the current knowledge on this most relevant clinical topic, focusing on bladder cancer, going from basic science to ongoing clinical trials and available clinical evidence. Finally, a critical analysis of published data is provided, and an original panel of biomarkers, able to select the right patients for treatments, based on patient-specific immune profiling, is proposed.

Abstract

In contrast with other strategies, immunotherapy is the only treatment aimed at empowering the immune system to increase the response against tumor growth. Immunotherapy has a role in the treatment of bladder cancer (BC) due to these tumors’ high tumor mutational burden (TMB) and mostly prominent immune infiltrate. The therapy or combination has to be adjusted to the tumor’s immunobiology. Recently, a new class of immunotherapeutic agents, immune checkpoint inhibitors (ICI), has shown potential in increasing treatment chances for patients with genitourinary cancers, improving their oncological outcomes. The clinical efficacy of ICI has been shown in both the first-line treatment of cisplatin-ineligible patients, with programmed death ligand 1 (PD-L1)-positive tumors (atezolizumab, pembrolizumab), and in second-line settings, for progression after platinum-based chemotherapy (atezolizumab, pembrolizumab, and nivolumab for FDA and EMA; durvalumab and avelumab for FDA alone). Predicting the response to ICI is important since only a subset of patients undergoing ICI therapy develop a concrete and lasting response. Most of the patients require a different therapy or therapy combination to achieve tumor control. The cancer immunity cycle provides a conceptual framework to assist therapy selection. Biomarkers to predict response to ICI must identify where the cancer immunity cycle is disrupted. We reviewed the current knowledge on ICI treatment in BC, going from basic science to current data and available clinical evidence. Secondly, a critical analysis of published data is provided, and an original panel of biomarkers able to predict response to ICI treatment, based on tumor-specific immune profiling, is proposed.

Impact of prior intravesical bacillus Calmette-Guerin therapy on the effectiveness of pembrolizumab for patients with metastatic urothelial carcinoma

OBJECTIVE

The aim of this study was to determine whether a history of treatment for non-muscle invasive bladder cancer (NMIBC), including intravesical bacillus Calmette-Guerin (BCG) therapy, affects the treatment outcomes of pembrolizumab in patients with metastatic, chemo-resistant urothelial carcinoma (UC).

MATERIALS AND METHODS

The clinicopathological data of 755 patients with metastatic, chemo-resistant UC who received pembrolizumab were retrospectively reviewed. Best overall response and overall survival (OS) from the initiation of pembrolizumab were analyzed with regard to the history of NMIBC treatment and BCG usage using propensity score matching (PSM).

RESULTS

A total of 155 (20.5%) patients had a history of NMIBC treatment, of which 97 (12.8%) had received intravesical BCG therapy. When compared to patients without a NMIBC history (median 10.0 months), the OS from the initiation of pembrolizumab for patients with a NMIBC history (13.3 months, HR [95% CI] 0.79 [0.62-1.02], P = 0.073), those with a NMIBC history and BCG (12.1 months, HR 0.87 [0.64-1.17], P = 0.356), or those with a NMIBC history but not BCG (14.5 months, HR 0.68 [0.45-1.12], P = 0.061) were not significantly different. This tendency was robust after 1:1 or 1:2 PSMs. The objective response rate (ORR, 24.5% vs. 31.0%, P = 0.222) and disease control rate (DCR, 56.1% vs. 52.1%, P = 0.501) of the 155 patients with an NMIBC history did not differ from those of 155 matched patients without an NMIBC history. Among those with an NMIBC history, the prior use of BCG did not affect OS (with vs. without BCG, 12.1 vs. 14.5 months, HR 1.29 [0.80-2.09], P = 0.295), ORR (24.5% vs. 34.0%, P = 0.298) or DCR (57.1% vs. 56.0%, P = 0.908). The ORR in BCG-treated patients was significantly lower than that in those without a NMIBC history (19.8% vs. 33.3%, P = 0.042), whereas DCR between the 2 groups did not differ significantly (55.8% vs. 54.4%, P = 0.855).

CONCLUSIONS

Our risk-adjusted analyses revealed that a history of prior NMIBC treatment, including intravesical BCG therapy, did not affect the treatment outcomes of pembrolizumab in metastatic UC patients.

Checkpoint inhibitors in BCG-unresponsive nonmuscle invasive bladder cancer: can they help spare the bladder?

Intravesical BCG therapy has been for years, the standard of care in nonmuscle-invasive bladder cancer. But upon recurrence/relapse, radical cystectomy is imposed, due to the paucity of other therapeutic options. Immunotherapy has been revolutionizing cancer treatment, and its indications continue to broaden. It has been approved for the treatment of advanced urothelial cancer of the bladder, mainly as a second-line therapy. Its activity is being studied in nonmuscle-invasive bladder cancer that is not responsive to BCG; we herein report the trials investigating these checkpoint inhibitors (pembrolizumab, nivolumab, atezolizumab, durvalumab and avelumab) in this particular setting.

NFκB-Activated COX2/PGE2/EP4 Axis Controls the Magnitude and Selectivity of BCG-Induced Inflammation in Human Bladder Cancer Tissues

Simple Summary

The clinical effectiveness of Bacillus Calmette-Guérin (BCG) is limited to patients with early stages of bladder cancer (BlCa) and its effects are often transient. To understand the mechanisms limiting the effectiveness of BCG, we evaluated its impact on the human BlCa tumor microenvironment (TME) and the feasibility of its pharmacologic modulation. We observed that BCG non-selectively induces both CTL-attracting chemokines and Treg/MDSC attractants and suppressive factors in human BlCa tissue explants, in a mechanism involving NFκB-induced PGE₂ synthesis and EP4 signaling. In contrast to non-selective impact of NFκB blockade on BCG-induced inflammation, the PGE₂ antagonism selectively enhanced the BCG-driven production of CTL attractants but eliminated the induction of Treg/MDSC attractants and suppressive factors, enhancing the CTL migration but reducing Treg attraction to BCG-treated BlCa. Since intratumoral CTL accumulation predicts long term patient outcomes and the effectiveness of cancer immunotherapies, our data indicates the feasibility of targeting the PGE₂-chemokine interplay to enhance the therapeutic effects of BCG.

Abstract

Bacillus Calmette-Guérin (BCG) is commonly used in the immunotherapy of bladder cancer (BlCa) but its effectiveness is limited to only a fraction of patients. To identify the factors that regulate the response of human BlCa tumor microenvironment (TME) to BCG, we used the ex vivo whole-tissue explant model. The levels of COX2 in the BCG-activated explants closely correlated with the local production of Treg- and MDSCS attractants and suppressive factors, while the baseline COX2 levels did not have predictive value. Accordingly, we observed that BCG induced high levels of MDSC- and Treg-attracting chemokines (CCL22, CXCL8, CXCL12) and suppressive factors (IDO1, IL-10, NOS2). These undesirable effects were associated with the nuclear translocation of phosphorylated NFκB, induction of COX2, the key enzyme controlling PGE₂ synthesis, and elevation of a PGE₂ receptor, EP4. While NFκB blockade suppressed both the desirable and undesirable components of BCG-driven inflammation, the inhibitors of PGE₂ synthesis (Celecoxib or Indomethacin) or signaling (EP4-selective blocker, ARY-007), selectively eliminated the induction of MDSC/Treg attractants and immunosuppressive factors but enhanced the production of CTL attractants, CCL5, CXCL9 and CXCL10. PGE₂ blockade allowed for the selectively enhanced migration of CTLs to the BCG-treated BlCa samples and eliminated the enhanced migration of Tregs. Since the balance between the CTLs and suppressive cells in the TME predicts the outcomes in patients with BlCa and other diseases, our data help to elucidate the mechanisms which limit the effectiveness of BCG therapies and identify new targets to enhance their therapeutic effects.