Apalutamide versus bicalutamide in combination with androgen deprivation therapy for metastatic hormone sensitive prostate cancer.

The objective of this study is to compare the efficacy of apalutamide and bicalutamide in combination with androgen deprivation therapy in patients with metastatic hormone-sensitive prostate cancer (mHSPC). We retrospectively collected the data of about 330 patients with metastatic hormone-sensitive prostate cancer at our hospital and affiliated hospitals between December 2013 and August 2023. Sixty-one patients were administered apalutamide (240 mg/day) with androgen deprivation therapy (group A), and 269 patients were administered bicalutamide (80 mg/day) with androgen deprivation therapy (group B). Propensity score matching was used to adjust for clinical background factors between the two groups. PSA progression-free survival and overall survival were significantly longer in group A than in group B among the matched patients. Apalutamide therapy was a significant independent factor for OS in matched patients. The second progression-free survival of group A was significantly longer than that of group B in matched patients. Patients treated with apalutamide achieved ≥ 90% PSA decline from baseline faster and in larger numbers than those with bicalutamide. Apalutamide combined with ADT may be superior to bicalutamide alone in terms of OS and PSA-PFS in patients with mHSPC.

Treatment impact of newly approved therapeutic agents for metastatic urothelial carcinoma in Japan: a single-center retrospective study.

Although recent clinical trials of new therapeutic agents for metastatic urothelial carcinoma have shown prolonged overall survival, there are few real-world evidence. To assess the impact of new therapeutic agents, we performed retrospective analysis for consecutive 158 metastatic urothelial carcinoma patients who performed systemic therapy in our institution between May 2008 and August 2023. We defined a period from May 2008 to December 2017, when pembrolizumab was first introduced to the clinical setting in the new therapeutic agents for metastatic urothelial carcinoma in Japan, as "pre new drug era" and a period from January 2018 to August 2023 as "post new drug era". We compared overall survival between pre- and post- new drug era using Kaplan-Meier method with log rank test. Median overall survival of pre- and post- new drug era were 14.5 months (95% confidence intervals: 11.6-16.7) and 23.1 months (95% confidence intervals: 14.5-NA), respectively (p < 0.001). Five-year survival rate of pre- and post- new drug era was 7.0% (95% confidence intervals: 2.3-15.3) and 36.3% (95% confidence intervals: 21.4-51.5), respectively. Multivariable Cox proportional hazards regression analysis of factors associated with overall survival showed that enfortumab vedotin administration, administration of second-line or more systemic therapy, best overall response of SD, PR and CR in first-line systemic therapy, higher serum albumin and lower CRP were factors for overall survival prolongation. Introduction of new therapeutic agents for metastatic urothelial carcinoma contributed to the improvement of overall survival in comparison with the era without these agents.

Predictive factors for the efficacy of abiraterone acetate therapy in high-risk metastatic hormone-sensitive prostate cancer patients.

PURPOSE: There is a discrepancy in the efficacy of abiraterone acetate for overall survival (OS) in patients with high-risk metastatic hormone-sensitive prostate cancer (mHSPC). This study aimed to identify predictive factors for the efficacy of abiraterone acetate for OS in high-risk mHSPC patients by analyzing them over a longer observation period. METHODS: Five hundred high-risk mHSPC patients were retrospectively identified at our hospital and affiliated hospitals in the Kindai Oncology Study Group and Kyoto Prefectural University of Medicine Oncology Study Group between December 2013 and March 2022. Two hundred patients were treated with abiraterone acetate (1000 mg/day) plus prednisolone (5 mg/day) combined with androgen deprivation therapy (ADT). A total of 300 patients were treated with bicalutamide (80 mg/day) in combination with ADT. RESULTS: OS was not significantly different between the two treatments in the overall cohort (p = 0.1643). In the subgroup without Gleason pattern 5 at the primary lesion, OS was significantly better in patients treated with abiraterone acetate than in those treated with bicalutamide (p = 0.0192). In the subgroup with Gleason pattern 5 at the primary lesion, no significant difference was found between the two treatments (p = 0.1799). Univariate and multivariate analyses in the subgroup without Gleason pattern 5 at the primary lesion suggested that abiraterone therapy may be an important and independent predictor of OS in high-risk mHSPC patients. CONCLUSION: The presence of Gleason pattern 5 at the primary lesion may be a predictor for high-risk mHSPC patients who could benefit from abiraterone acetate treatment.

Human Vγ9Vδ2 T cells exert anti-tumor activity independently of PD-L1 expression in tumor cells.

Human γδ T cells expressing Vγ9Vδ2 T cell receptors play a crucial role in the innate immune system and have an attracted interest as effector cells in adoptive cellular immunotherapy. However, the efficacy of adoptive cellular immunotherapy for the treatment of tumors requires overcoming the immunosuppressive microenvironment. αß T cell inhibition in the tumor microenvironment is associated with programmed death-ligand 1 (PD-L1) expression level. Vγ9Vδ2 T cells (abbreviated as γδ T cells here) exert potent cytotoxic effects in various cancers; however, γδ T cell activity in relation to the level of PD-L1 expression in cancer cells remains unclear, and the association between the PD-1/PD-L1 axis and γδ T cell cytotoxicity needs to be investigated. In this study, PD-1 blockade did not increase the cytotoxicity of γδ T cells against PD-L1high cancer cells. However, the anti-PD-L1 monoclonal antibody (mAb) enhanced the cytotoxicity of γδ T cells against a subset of cancer cells, whereas PD-L1 knockdown did not increase the cytotoxicity of γδ T cells. We also found that the expression levels of PD-L1 were positively correlated with the changes of γδ T cells cytotoxicity induced by anti-PD-L1 mAb. These observations suggest that anti-PD-L1 mAb treatment adds ADCC activity to the cytotoxicity of γδ T cells itself against PD-L1high cancer cells. The present results suggest that ex vivo expanded γδ T cells have antitumor activity independently of PD-L1 expression and may be promising effector cells for γδ T cell immunotherapy.

Strategies to Improve the Antitumor Effect of γδ T Cell Immunotherapy for Clinical Application.

Human γδ T cells show potent cytotoxicity against various types of cancer cells in a major histocompatibility complex unrestricted manner. Phosphoantigens and nitrogen-containing bisphosphonates (N-bis) stimulate γδ T cells via interaction between the γδ T cell receptor (TCR) and butyrophilin subfamily 3 member A1 (BTN3A1) expressed on target cells. γδ T cell immunotherapy is classified as either in vivo or ex vivo according to the method of activation. Immunotherapy with activated γδ T cells is well tolerated; however, the clinical benefits are unsatisfactory. Therefore, the antitumor effects need to be increased. Administration of γδ T cells into local cavities might improve antitumor effects by increasing the effector-to-target cell ratio. Some anticancer and molecularly targeted agents increase the cytotoxicity of γδ T cells via mechanisms involving natural killer group 2 member D (NKG2D)-mediated recognition of target cells. Both the tumor microenvironment and cancer stem cells exert immunosuppressive effects via mechanisms that include inhibitory immune checkpoint molecules. Therefore, co-immunotherapy with γδ T cells plus immune checkpoint inhibitors is a strategy that may improve cytotoxicity. The use of a bispecific antibody and chimeric antigen receptor might be effective to overcome current therapeutic limitations. Such strategies should be tested in a clinical research setting.

Sphere-derived Prostate Cancer Stem Cells Are Resistant to γδ T Cell Cytotoxicity.

BACKGROUND/AIM: γδ T cells mediate cytotoxicity against prostate cancer (PCa) cells in vitro; however, the clinical efficacy of γδ T cell-targeted immunotherapy for recurrent and metastatic PCa is unsatisfactory. We hypothesized that the resistance of recurrent and metastatic PCa to γδ T cells is related to the presence of prostate cancer stem cells (PCSCs), and we examined their relationship. MATERIALS AND METHODS: PCa spheres (prostaspheres) were generated from five PCa cell lines, and their susceptibility to cytotoxicity by γδ T cells was investigated. Expression of stemness-related markers was evaluated by qRT-PCR. RESULTS: Prostasphere-derived cancer cells were resistant to lysis by γδ T cells and expressed higher levels of several stemness markers, including CD133, NANOG, SOX2, and OCT4, than the parental PCa cell lines. CONCLUSION: Ex vivo-expanded γδ T cells are not effective against PCSCs.

Low dose gemcitabine increases the cytotoxicity of human Vγ9Vδ2 T cells in bladder cancer cells in vitro and in an orthotopic xenograft model.

Human γδT cell immunotherapy is well tolerated and has shown promising results in clinical trials; however, its antitumor efficacy is limited, including results in solid tumors. Ex-vivo expanded γδT cell stimulated by zoledronic acid (ZOL) activates the γδT cell subpopulation of so called Vγ9Vδ2 T cells. To improve the clinical outcomes of Vγ9Vδ2 T cell (abbreviated as γδT cell here) immunotherapy, we aimed to increase the cytotoxicity of γδT cells by focusing on two issues: recognition of tumor cells by γδT cells and the effector (γδT cell)-to-target (tumor cell) (E/T) ratio. Ex vivo-expanded γδT cells showed potent cytotoxicity against urinary bladder cancer (UBC) cells in in vitro assays. Combination treatment with standard anticancer agents showed that low dose gemcitabine pretreatment significantly enhanced the cytotoxicity of γδT cells by upregulating the expression of MICA and MICB (MICA/B), which are tumor-associated antigens recognized by γδT cells. These effects were abrogated by small interfering RNA-mediated knockdown of MICA/B in UBC cells, suggesting that pre-exposing cancer cells to anticancer agents could be a promising strategy. A bladder instillation approach was used to increase the E/T ratio. The efficacy of ex vivo-expanded γδT cell immunotherapy was examined in an orthotopic xenograft model. In Vivo Imaging System analysis revealed the potent cytotoxicity of weekly intravesical administration of γδT cells, and weekly gemcitabine pretreatment enhanced the cytotoxicity of γδT cells in vivo. In conclusion, intravesical γδT cell immunotherapy and combination therapy with low dose gemcitabine may be a promising strategy in UBC.

[Spontaneous Subcapsular Renal Hemorrhage of Papillary Renal Cell Carcinoma].

A 75-year-old man with a history of chronic kidney disease (CKD) visited our emergency room after the sudden onset of severe right lower abdominal pain and nausea. Computed tomography (CT) showed right perirenal hematoma and renal tumor, which was diagnosed as a spontaneous rupture of the right renal tumor. It was difficult to correctly diagnose the tumor as benign or malignant with magnetic resonance imaging (MRI). Because of CKD, a shunt was implanted, and dynamic enhanced CT was performed. Dynamic enhanced CT showed a slightly enhanced area of the tumor, and it was diagnosed as renal cell carcinoma (RCC). Radical nephrectomy was performed, and he has not experienced recurrence within 7 months after the surgery. Pathological diagnosis was papillary renal carcinoma. Spontaneous renal hemorrhage is relatively uncommon, but the most common cause of spontaneous renal hemorrhage is renal cell carcinoma (26.1%). CT is useful for diagnosis, but it is not highly accurate. Therefore, it is necessary to discuss surgical indication carefully.