Treatment escalation and de-escalation of de-novo metastatic castration-sensitive prostate cancer.

Androgen receptor signaling inhibitors combined with androgen deprivation therapy have become the standard of care for metastatic castration-sensitive prostate cancer (mCSPC), regardless of tumor volume or risk. However, survival of approximately one-third of these patients has not improved, necessitating further treatment escalation. On the other hand, for patients with oligometastatic mCSPC, there is an emerging role for local radiation therapy. Although data remain scarce, it is expected that treatment of both primary tumor as well as metastasis-directed therapy may improve survival outcomes. In these patients, systemic therapy may be de-escalated to intermittent therapy. However, precise risk stratification is necessary for risk-based treatment escalation or de-escalation. In addition to risk stratification based on clinical parameters, research has been conducted to incorporate genomic and/or transcriptomic data into risk stratification. In future, an integrated risk model is expected to precisely stratify patients and guide treatment strategies. Here, we first review the transition of the standard treatment for mCSPC over the last decade and further discuss the newest concept of escalating or de-escalating treatment using a multi-modal approach based on the currently available literature.

[A Case of Metastatic Prostate Cancer with Neuroendocrine Differentiation with Long-Term Survival after Multidisciplinary Therapy].

A 74-year-old man visited the urology clinic with the chief complaint of urinary retention in December 2014. Serum level of initial prostate specific antigen (PSA) was 50 ng/ml and he was diagnosed with Gleason Score 4＋4 prostate adenocarcinoma with regional lymphadenopathy (cT3aN1M0). PSA level had declined after the treatment with combined androgen blockade. In November 2018, he was diagnosed with castration resistant prostate cancer (CRPC) as local progression was detected by computed tomography (CT) while PSA level did not increase. Since local symptoms worsened, resulting in repeated hematuria after the treatment with enzalutamide, palliative radiation therapy to the prostate (45 Gy) was performed. Five months later, follow-up CT showed multiple metastasis in bilateral lung and left testicle. Serum level of neuron-specific enolase (NSE) was 24.4 ng/ml without an elevated in serum PSA level. He received rebiopsy of the prostate, but no malignant findings were observed. Consequently, bilateral orchiectomy was performed for diagnosis of left testicular tumor. Pathological examination revealed metastasis of neuroendocrine prostate cancer (NEPC). Chemotherapy using cisplatin and irinotecan was administered after orchiectomy. Complete response of lung lesions was achieved and serum level of NSE decreased within normal range. No recurrence has been confirmed for 4 years after the completion of chemotherapy.

Co-delivery of oncolytic virus and chemotherapeutic modality: Vincristine against prostate cancer treatment: A potent viro-chemotherapeutic approach.

Prostate cancer is a prevalent carcinoma among males, and conventional treatment options are often limited. Cytotoxic chemotherapy, despite its drawbacks, remains a mainstay. We propose a targeted co-delivery approach using nanoscale delivery units for Oncolytic measles virus (OMV) and vincristine (VC) to enhance treatment efficacy. The HA-coated OMV + VC-loaded TCs nanoformulation is designed for targeted oncolytic activity in prostate cancer. The CD44 expression analysis in prostate cancer cell lines indicates a significantly high expression in PC3 cells. The optimization of nanoformulations using Design of Expert (DOE) is performed, and the preparation and characterization of HA-coated OMV + VC-loaded TCs nanoformulations are detailed showing average particle size 397.2 ± 0.01 nm and polydispersity index 0.122 with zeta potential 19.7 + 0.01 mV. Results demonstrate successful encapsulation efficiency with 2.4 × 106 TCID50/Ml and sustained release of OMV and VC from the nanoformulation for up to 72 h. In vitro, assays reveal potent anticancer activity at 10 ± 0.71% cell viability in PC3 cells compared to 73 ± 0.66% in HPrEC and significant morphological changes at 90 µg/ml in dose and time-dependent manner. The co-formulation showed positive cell death 49.5 ± 0.02% at 50 µg PI/ml in PBS and 54.3% cell cycle arrest at the G2/M phase, 8.1% G0/G1 and 5.7% at S phase, with significant mitochondrial membrane potential (MMP) at 50 µg/ml, as assessed by flow cytometry (FACS). The surface-integrating ligand approach enhances the targeted delivery of the oncolytic virus and chemotherapeutic drug, presenting a potential alternative for prostate cancer treatment and suggested that co-administering VC and OMV in a nanoformulation could improve therapeutic outcomes while reducing chemotherapeutic drug doses.

Seminal Papers in Urology: Darolutamide and survival in metastatic, hormone-sensitive prostate cancer.

The ARASENS trial recruited 1306 men with metastatic hormone sensitive prostate cancer. It investigated the effect of androgen deprivation therapy (ADT) and systemic therapy docetaxel in combination with a third novel drug - daralutamide, compared with placebo on overall survival. Triple therapy with ADT, docetaxel and darolutamide resulted in improved overall survival rates as compared with ADT, docetaxel and placebo (HR 0.68; 95% CI, 0.57-0.80; p < 0.001). The side effect profile for both treatments was similar. This randomised, double blinded, placebo controlled study, was assessed to have a low risk of bias using the Cochrane Risk of Bias 2 tool.

Prostate tissue ablation and drug delivery by an image-guided injectable ionic liquid in ex vivo and in vivo models.

Benign prostatic hyperplasia and prostate cancer are often associated with lower urinary tract symptoms, which can severely affect patient quality of life. To address this challenge, we developed and optimized an injectable compound, prostate ablation and drug delivery agent (PADA), for percutaneous prostate tissue ablation and concurrently delivered therapeutic agents. PADA is an ionic liquid composed of choline and geranic acid mixed with anticancer therapeutics and a contrast agent. The PADA formulation was optimized for mechanical properties compatible with hand injection, diffusion capability, cytotoxicity against prostate cells, and visibility of an x-ray contrast agent. PADA also exhibited antibacterial properties against highly resistant clinically isolated bacteria in vitro. Ultrasound-guided injection, dispersion of PADA in the tissue, and tissue ablation were tested ex vivo in healthy porcine, canine, and human prostates and in freshly resected human tumors. In vivo testing was conducted in a murine subcutaneous tumor model and in the canine prostate. In all models, PADA decreased the number of viable cells in the region of dispersion and supported the delivery of nivolumab throughout a portion of the tissue. In canine survival experiments, there were no adverse events and no impact on urination. The injection approach was easy to perform under ultrasound guidance and produced a localized effect with a favorable safety profile. These findings suggest that PADA is a promising therapeutic prostate ablation strategy to treat lower urinary tract symptoms.

Discovery of a peptide proteolysis-targeting chimera (PROTAC) drug of p300 for prostate cancer therapy.

BACKGROUND: The E1A-associated protein p300 (p300) has emerged as a promising target for cancer therapy due to its crucial role in promoting oncogenic signaling pathways in various cancers, including prostate cancer. This need is particularly significant in prostate cancer. While androgen deprivation therapy (ADT) has demonstrated promising efficacy in prostate cancer, its long-term use can eventually lead to the development of castration-resistant prostate cancer (CRPC) and neuroendocrine prostate cancer (NEPC). Notably, p300 has been identified as an important co-activator of the androgen receptor (AR), highlighting its significance in prostate cancer progression. Moreover, recent studies have revealed the involvement of p300 in AR-independent oncogenes associated with NEPC. Therefore, the blockade of p300 may emerge as an effective therapeutic strategy to address the challenges posed by both CRPC and NEPC. METHODS: We employed AI-assisted design to develop a peptide-based PROTAC (proteolysis-targeting chimera) drug that targets p300, effectively degrading p300 in vitro and in vivo utilizing nano-selenium as a peptide drug delivery system. FINDINGS: Our p300-targeting peptide PROTAC drug demonstrated effective p300 degradation and cancer cell-killing capabilities in both CRPC, AR-negative, and NEPC cells. This study demonstrated the efficacy of a p300-targeting drug in NEPC cells. In both AR-positive and AR-negative mouse models, the p300 PROTAC drug showed potent p300 degradation and tumor suppression. INTERPRETATION: The design of peptide PROTAC drug targeting p300 is feasible and represents an efficient therapeutic strategy for CRPC, AR-negative prostate cancer, and NEPC. FUNDING: The funding details can be found in the Acknowledgements section.

[A Case of Granulocyte Colony-Stimulating Factor-Related Aortitis that Developed during the Treatment of Advanced Prostate Cancer with Neuroendocrine Differentiation].

An 81-year-old man with prostate cancer (cT3aN0M0), who had been undergoing hormonal therapy for 4 years and had maintained low prostate specific antigen levels, developed metastasized pelvic lymph nodes. A tissue biopsy revealed neuroendocrine differentiation of prostate cancer in the metastatic lymph nodes. Consequently, chemotherapy with carboplatin＋etoposide was initiated. During the first course, filgrastim was administered for 2 days due to a drop in his neutrophil count to 230/µl. During the second course, pegfilgrastim was administered as prophylaxis on day 4. However, on day 10 of the second course, he started to develop a fever and fatigue. Suspecting infection, antibiotics were administered, but failed to ameliorate his symptoms. On day 14, plain computed tomography revealed signs of aortic inflammation. Given the lack of improvement even after one week of antibiotic therapy, steroid treatment was initiated on the suspicion of granulocyte colony-stimulating factor (G-CSF) -induced aortitis, which rapidly improved his symptoms. Therefore, when encountering a case in which a fever remains unresponsive to antibiotics during chemotherapy with G-CSF agents, a differential diagnosis of aortic inflammation caused by G-CSF agents needs to be considered.

The marine-derived HIF-1α inhibitor, Yardenone 2, reduces prostate cancer cell proliferation by targeting HIF-1 target genes.

BACKGROUND: Prostate cancer (PCa) ranks as the second most prevalent cancer in men, with advanced stages posing significant treatment challenges. Given its solid tumor nature, PCa is highly susceptible to hypoxia, a condition associated with resistance to radiation and chemotherapy, metastasis, and unfavorable patient outcomes. Hypoxia-inducible factors (HIFs) play a pivotal role in cancer cell adaptation to hypoxic environments, contributing to treatment resistance. Consequently, inhibitors targeting HIFs hold promise for cancer therapy. METHODS: In this study, we aimed to characterize novel HIF-1α inhibitors including Sodwanones A (1), B (2), C (3), G (4) and Yardenone 2 (5) isolated from marine sponges belonging to the Axinella genus. Our investigation evaluated the impact of these compounds on various aspects of HIF-1α regulation, including stabilization, nuclear localization, expression of HIF-1 target genes (while sparing HIF-2 target genes), cellular metabolism, as well as cell proliferation and viability in prostate cells under hypoxic conditions. RESULTS: Our findings revealed that among the compounds tested, Yardenone 2 exhibited notable effects in hypoxia: it destabilized HIF-1α at the protein level, decreased its nuclear localization, selectively altered the expression of HIF-1 target genes, and restrained cell proliferation in aggressive PC3 prostate cancer cells as well as in an MSK-PCa3 patient-derived organoid line. Moreover, it affected the morphology of these organoid. Yardenone 2 was also compared to Docetaxel, a specific microtubule inhibitor and a drug used in the treatment of prostate cancer. The comparison between the two compounds revealed notable differences, such as a lack of specificity to hypoxic cells of Docetaxel. CONCLUSION: These results mark the first demonstration that Yardenone 2 functions as a cytostatic-like inhibitor impacting microtubules, specifically targeting hypoxic cancer cells. This discovery suggests a promising avenue for novel therapeutic interventions in prostate cancer.

Bone Pain and Survival Among Patients With Metastatic, Hormone-Sensitive Prostate Cancer: A Secondary Analysis of the SWOG-1216 Trial.

Importance: The presence of bone pain is significantly associated with worse overall survival (OS) in patients with castration-resistant prostate cancer. However, there are few data regarding bone pain and survival outcomes in the context of metastatic, hormone-sensitive prostate cancer (MHSPC). Objective: To compare survival outcomes among patients with MHSPC by presence or absence of baseline bone pain at diagnosis. Design, Setting, and Participants: This post hoc secondary analysis, conducted from September 1 to December 31, 2023, used patient-level data from SWOG-1216, a phase 3, prospective randomized clinical trial that enrolled patients with newly diagnosed MHSPC from 248 academic and community centers across the US from March 1, 2013, to July 15, 2017. All patients in the intention-to-treat population who had available bone pain status were eligible and included in this secondary analysis. Interventions: In the SWOG-1216 trial, patients were randomized (1:1) to receive either androgen deprivation therapy (ADT) with orteronel, 300 mg orally twice daily (experimental group), or ADT with bicalutamide, 50 mg orally daily (control group), until disease progression, unacceptable toxic effects, or patient withdrawal. Main Outcomes and Measures: Overall survival was the primary end point; progression-free survival (PFS) and prostate-specific antigen (PSA) response were secondary end points. Cox proportional hazards regression models were used for both univariable and multivariable analyses adjusting for age, treatment type, Gleason score, disease volume, Zubrod performance status, and PSA level. Results: Of the 1279 male study participants, 301 (23.5%) had baseline bone pain at MHSPC diagnosis and 896 (70.1%) did not. Bone pain status was unavailable in 82 patients (6.4%). The median age of the 1197 patients eligible and included in this secondary analysis was 67.6 years (IQR, 61.8-73.6 years). Compared with patients who did not experience bone pain, those with baseline bone pain were younger (median age, 66.0 [IQR, 60.1-73.4] years vs 68.2 [IQR, 62.4-73.7] years; P = .02) and had a higher incidence of high-volume disease (212 [70.4%] vs 373 [41.6%]; P < .001). After adjustment, bone pain was associated with shorter PFS and OS. At a median follow-up of 4.0 years (IQR, 2.5-5.4 years), patients with bone pain had median PFS of 1.3 years (95% CI, 1.1-1.7 years) vs 3.7 years (95% CI, 3.3-4.2 years) in patients without initial bone pain (adjusted hazard ratio [AHR], 1.46; 95% CI, 1.22-1.74; P < .001) and OS of 3.9 years (95% CI, 3.3-4.8 years) vs not reached (NR) (95% CI, 6.6 years to NR) in patients without initial bone pain (AHR, 1.66; 95% CI, 1.34-2.05; P < .001). Conclusions and Relevance: In this post hoc secondary analysis of the SWOG-1216 randomized clinical trial, patients with baseline bone pain at MHSPC diagnosis had worse survival outcomes than those without bone pain. These data suggest prioritizing these patients for enrollment in clinical trials, may aid patient counseling, and indicate that the inclusion of bone pain in prognostic models of MHSPC may be warranted. Trial Registration: ClinicalTrials.gov Identifier: NCT01809691.

External validation of the barcelona magnetic resonance imaging predictive model for detecting significant prostate cancer including men receiving 5-alpha reductase inhibitors.

PURPOSE: To validate the Barcelona-magnetic resonance imaging predictive model (BCN-MRI PM) for clinically significant prostate cancer (csPCa) in Catalonia, a Spanish region with 7.9 million inhabitants. Additionally, the BCN-MRI PM is validated in men receiving 5-alpha reductase inhibitors (5-ARI). MATERIALS AND METHODS: A population of 2,212 men with prostate-specific antigen serum level > 3.0 ng/ml and/or a suspicious digital rectal examination who underwent multiparametric MRI and targeted and/or systematic biopsies in the year 2022, at ten participant centers of the Catalonian csPCa early detection program, were selected. 120 individuals (5.7%) were identified as receiving 5-ARI treatment for longer than a year. The risk of csPCa was retrospectively assessed with the Barcelona-risk calculator 2 (BCN-RC 2). Men undergoing 5-ARI treatment for less than a year were excluded. CsPCa was defined when the grade group was ≥ 2. RESULTS: The area under the curve of the BCN-MRI PM in 5-ARI naïve men was 0.824 (95% CI 0.783-0.842) and 0.849 (0.806-0.916) in those receiving 5-ARI treatment, p 0.475. Specificities at 100, 97.5, and 95% sensitivity thresholds were to 2.7, 29.3, and 39% in 5-ARI naïve men, while 43.5, 46.4, and 47.8%, respectively in 5-ARI users. The application of BCN-MRI PM would result in a reduction of 23.8% of prostate biopsies missing 5% of csPCa in 5-ARI naïve men, while reducing 25% of prostate biopsies without missing csPCa in 5-ARI users. CONCLUSIONS: The BCN-MRI PM has achieved successful validation in Catalonia and, notably, for the first time, in men undergoing 5-ARI treatment.

Cost-effectiveness analysis of rezvilutamide versus bicalutamide in the treatment of metastatic hormone-sensitive prostate cancer.

OBJECTIVES: The economic implications of combining rezvilutamide with androgen deprivation therapy (ADT) remain uncertain, despite the observed survival advantages compared with bicalutamide plus ADT. Therefore, this study evaluates the cost-effectiveness of rezvilutamide plus ADT as the first-line treatment of metastatic hormone-sensitive prostate cancer (mHSPC) from the perspective of the Chinese healthcare system. DESIGN: A partitioned survival model was developed to assess the cost-effectiveness of rezvilutamide combined with ADT. Clinical data were obtained from the CHART trial. Costs and utility values were obtained from local estimate and published literature. Only direct medical costs were included in the model. INTERVENTIONS: Rezvilutamide was administered at 240 mg daily or bicalutamide at 50 mg daily until progression. OUTCOME MEASURES: The main outputs of the model included costs and quality-adjusted life years (QALYs), which were used to determine the incremental cost-effectiveness ratio (ICER). One-way and probabilistic sensitivity analysis (PSA) were used to explore model uncertainties. RESULTS: The rezvilutamide group showed an expected gain of 2.28 QALYs and an incremental cost of US$60 758.82 compared with the bicalutamide group. The ICER for rezvilutamide group versus bicalutamide group was US$26 656.94 per QALY. The variables with the greatest impact on the model results were the utility for progression-free survival state and the price of rezvilutamide. PSA revealed that rezvilutamide group had 100% probability of being cost-effective at a willingness-to-pay threshold of US$35707.5 per QALY. CONCLUSION: Rezvilutamide in combination with ADT is more cost-effective compared with bicalutamide plus ADT as the first-line treatment of mHSPC from the perspective of the Chinese healthcare system.

Magnetic resonance imaging-based radiomics nomogram for the evaluation of therapeutic responses to neoadjuvant chemohormonal therapy in high-risk non-metastatic prostate cancer.

PURPOSE: The aim of this study was to assess the potential application of a radiomics features-based nomogram for predicting therapeutic responses to neoadjuvant chemohormonal therapy (NCHT) in patients with high-risk non-metastatic prostate cancer (PCa). METHODS: Clinicopathologic information was retrospectively collected from 162 patients with high-risk non-metastatic PCa receiving NCHT and radical prostatectomy at our center. The postoperative pathological findings were used as the gold standard for evaluating the efficacy of NCHT. The least absolute shrinkage and selection operator (LASSO) was conducted to develop radiomics signature. Multivariate logistic regression analyses were conducted to identify the predictors of a positive pathological response to NCHT, and a nomogram was constructed based on these predictors. RESULTS: Sixty-three patients (38.89%) experienced positive pathological response to NCHT. Receiver operating characteristic analyses showed that the area under the curve (AUC) of periprostatic fat (PPF) radiomics signature was 0.835 (95% CI, 0.754-0.898), while the AUC of intratumoral radiomics signature was 0.822 (95% CI, 0.739-0.888). Multivariate logistic regression analysis revealed that PSA level, PPF radiomics signature and intratumoral radiomics signature were independent predictors of positive pathological response. A nomogram based on these three predictors was constructed. The AUC was 0.908 (95% CI, 0.839-0.954). The Hosmer-Lemeshow goodness-of-fit test showed that the nomogram was well calibrated. Decision curve analysis revealed the favorable clinical practicability of the nomogram. The nomogram was successfully validated in the validation cohort. Kaplan-Meier analyses showed that nomogram and positive pathological response were significantly related with survival of PCa. CONCLUSION: The radiomics-clinical nomogram based on mpMRI radiomics features exhibited superior predictive ability for positive pathological response to NCHT in high-risk non-metastatic PCa.

Epigenetic regulation of androgen dependent and independent prostate cancer.

Prostate cancer is one of the most common malignancies among men worldwide. Besides genetic alterations, epigenetic modulations including DNA methylation, histone modifications and miRNA mediated alteration of gene expression are the key driving forces for the prostate tumor development and cancer progression. Aberrant expression and/or the activity of the epigenetic modifiers/enzymes, results in aberrant expression of genes involved in DNA repair, cell cycle regulation, cell adhesion, apoptosis, autophagy, tumor suppression and hormone response and thereby disease progression. Altered epigenome is associated with prostate cancer recurrence, progression, aggressiveness and transition from androgen-dependent to androgen-independent phenotype. These epigenetic modifications are reversible and various compounds/drugs targeting the epigenetic enzymes have been developed that are effective in cancer treatment. This chapter focuses on the epigenetic alterations in prostate cancer initiation and progression, listing different epigenetic biomarkers for diagnosis and prognosis of the disease and their potential as therapeutic targets. This chapter also summarizes different epigenetic drugs approved for prostate cancer therapy and the drugs available for clinical trials.

Systemic therapy landscape of advanced prostate cancer.

Prostate cancer is the most commonly diagnosed cancer in American men and 2nd leading cause of cancer-related deaths in the United States. Androgen deprivation therapy (ADT) is the backbone of treatment for advanced prostate cancer. Over the past several decades a number of new therapeutics, such as novel androgen receptor pathway inhibitors, targeted agents and radionuclide therapies, have been introduced for the treatment of prostate cancers. These agents have been demonstrated to improve clinical outcomes of prostate cancer patients in randomized clinical trials. In addition, new therapeutic strategies, such as early intensification of ADT, novel treatment combinations, and treatment sequencing, are expected to improve outcomes further. In this clinical review, we discuss the changing treatment landscape for advanced prostate cancer with a focus on new therapeutics.

Single-cell analysis of treatment-resistant prostate cancer: Implications of cell state changes for cell surface antigen-targeted therapies.

Targeting cell surface molecules using radioligand and antibody-based therapies has yielded considerable success across cancers. However, it remains unclear how the expression of putative lineage markers, particularly cell surface molecules, varies in the process of lineage plasticity, wherein tumor cells alter their identity and acquire new oncogenic properties. A notable example of lineage plasticity is the transformation of prostate adenocarcinoma (PRAD) to neuroendocrine prostate cancer (NEPC)-a growing resistance mechanism that results in the loss of responsiveness to androgen blockade and portends dismal patient survival. To understand how lineage markers vary across the evolution of lineage plasticity in prostate cancer, we applied single-cell analyses to 21 human prostate tumor biopsies and two genetically engineered mouse models, together with tissue microarray analysis on 131 tumor samples. Not only did we observe a higher degree of phenotypic heterogeneity in castrate-resistant PRAD and NEPC than previously anticipated but also found that the expression of molecules targeted therapeutically, namely PSMA, STEAP1, STEAP2, TROP2, CEACAM5, and DLL3, varied within a subset of gene-regulatory networks (GRNs). We also noted that NEPC and small cell lung cancer subtypes shared a set of GRNs, indicative of conserved biologic pathways that may be exploited therapeutically across tumor types. While this extreme level of transcriptional heterogeneity, particularly in cell surface marker expression, may mitigate the durability of clinical responses to current and future antigen-directed therapies, its delineation may yield signatures for patient selection in clinical trials, potentially across distinct cancer types.

A Synergistic Strategy Combining Chemotherapy and Photodynamic Therapy to Eradicate Prostate Cancer.

Prostate cancer is the most prevalent cancer among men in the United States and is a leading cause of cancer-related death. Prostate specific membrane antigen (PSMA) has been established as a biomarker for prostate cancer diagnosis and treatment. This study aimed to develop a novel theranostic agent, PSMA-1-MMAE-Pc413, which integrates a PSMA-targeting ligand, the photosensitizer Pc413, and the microtubular inhibitor monomethyl auristatin E (MMAE) for synergistic therapeutic efficacy. In vitro uptake studies revealed that PSMA-1-MMAE-Pc413 demonstrated selective and specific uptake in PSMA-positive PC3pip cells but not in PSMA-negative PC3flu cells, with the uptake in PC3pip cells being approximately three times higher. In vitro cytotoxicity assays showed that, when exposed to light, PSMA-1-MMAE-Pc413 had a synergistic effect, leading to significantly greater cytotoxicity in PSMA-positive cells (IC50 = 2.2 nM) compared to PSMA-1-Pc413 with light irradiation (IC50 = 164.9 nM) or PSMA-1-MMAE-Pc413 without light irradiation (IC50 = 12.6 nM). In vivo imaging studies further demonstrated the selective uptake of PSMA-1-MMAE-Pc413 in PC3pip tumors. In in vivo studies, PSMA-1-MMAE-Pc413 dramatically improves the therapeutic outcome for prostate cancer by providing a synergistic effect that surpasses the efficacy of each treatment modality alone in PC3pip tumors. These findings suggest that PSMA-1-MMAE-Pc413 has strong potential for clinical application in improving prostate cancer treatment.

Mitochondrial Elongation and ROS-Mediated Apoptosis in Prostate Cancer Cells under Therapy with Apalutamide and Complex I Inhibitor.

Metabolic reprogramming and mitochondrial dynamics are pivotal in prostate cancer (PCa) progression and treatment resistance, making them essential targets for therapeutic intervention. In this study, we investigated the effects of the androgen receptor antagonist apalutamide (ARN) and the mitochondrial electron transport chain complex I inhibitor IACS-010759 (IACS) on the mitochondrial network architecture and dynamics in PCa cells. Treatment with ARN and/or IACS induced significant changes in mitochondrial morphology, particularly elongation, in androgen-sensitive PCa cells. Additionally, ARN and IACS modulated the mitochondrial fission and fusion processes, indicating a convergence of metabolic and androgen-signaling pathways in shaping mitochondrial function. Notably, the combination treatment with ARN and IACS resulted in increased apoptotic cell death and mitochondrial oxidative stress selectively in the androgen-sensitive PCa cells. Our findings highlight the therapeutic potential of targeting mitochondrial metabolism in prostate cancer and emphasize the need for further mechanistic understanding to optimize treatment strategies and improve patient outcomes.

Feasibility study of ADCs targeting TROP-2, HER2, and CD46 in Ductal Adenocarcinoma and Intraductal Carcinoma of the prostate.

BACKGROUND: Ductal Adenocarcinoma (DAC) and Intraductal Carcinoma of the Prostate (IDC-P) respond poorly to all the currently available conventional therapies. Given their accurate and efficient elimination of cancer cells, Antibody-Drug Conjugates (ADCs) have become one of the most promising anticancer treatments. However, no ADCs have so far been approved for Prostate Cancer (PCa) treatment. This study investigated TROP-2, HER2, and CD46 expression in DAC/IDC-P samples, indirectly analyzing their preliminary feasibility as therapeutic targets for future treatment of the two conditions. PATIENTS AND METHODS: We conducted a retrospective study involving 184 participants (87 DAC/IDC-P patients and 97 Prostatic Acinar Adenocarcinoma (PAC) patients with a Gleason score ≥ 8) without prior treatment between August 2017 and August 2022. Immunohistochemical staining was employed to detect the differential protein expressions of TROP-2, HER2, and CD46 in DAC/IDC-P, PAC, and normal prostate tissues. RESULTS: Compared to pure PAC tissues, TROP-2 expression was significantly higher in DAC/IDC-P and DAC/IDC-P-adjacent PAC tissues (H-score 68.8 vs. 43.8, p < 0.001, and 59.8 vs. 43.8, p = 0.022, respectively). No significant differences in HER2 expression were observed across different cancer tissues. Compared to both DAC/IDC-P-adjacent PAC and pure PAC tissues, CD46 expression was significantly higher in DAC/IDC-P tissues (42.3 vs. 28.6, p = 0.041, and 42.3 vs. 24.3, p = 0.0035, respectively). CONCLUSIONS: Herein, TROP-2 and CD46 expression was higher in DAC/IDC-P tissues than in pure PAC and normal prostate tissues. This finding implies that ADCs targeting the two proteins hold significant promise as potential future treatments for DAC/IDC-P.

Pentagalloyl Glucose (PGG) Exhibits Anti-Cancer Activity against Aggressive Prostate Cancer by Modulating the ROR1 Mediated AKT-GSK3ß Pathway.

Androgen-receptor-negative, androgen-independent (ARneg-AI) prostate cancer aggressively proliferates and metastasizes, which makes treatment difficult. Hence, it is necessary to continue exploring cancer-associated markers, such as oncofetal Receptor Tyrosine Kinase like Orphan Receptor 1 (ROR1), which may serve as a form of targeted prostate cancer therapy. In this study, we identify that Penta-O-galloyl-ß-D-glucose (PGG), a plant-derived gallotannin small molecule inhibitor, modulates ROR1-mediated oncogenic signaling and mitigates prostate cancer phenotypes. Results indicate that ROR1 protein levels were elevated in the highly aggressive ARneg-AI PC3 cancer cell line. PGG was selectively cytotoxic to PC3 cells and induced apoptosis of PC3 (IC50 of 31.64 µM) in comparison to normal prostate epithelial RWPE-1 cells (IC50 of 74.55 µM). PGG was found to suppress ROR1 and downstream oncogenic pathways in PC3 cells. These molecular phenomena were corroborated by reduced migration, invasion, and cell cycle progression of PC3 cells. PGG minimally and moderately affected RWPE-1 and ARneg-AI DU145, respectively, which may be due to these cells having lower levels of ROR1 expression in comparison to PC3 cells. Additionally, PGG acted synergistically with the standard chemotherapeutic agent docetaxel to lower the IC50 of both compounds about five-fold (combination index = 0.402) in PC3 cells. These results suggest that ROR1 is a key oncogenic driver and a promising target in aggressive prostate cancers that lack a targetable androgen receptor. Furthermore, PGG may be a selective and potent anti-cancer agent capable of treating ROR1-expressing prostate cancers.

Polydopamine-Based Nanoparticles for Synergistic Chemotherapy of Prostate Cancer.

Introduction: Immune regulatory small molecule JQ1 can block its downstream effector PD-L1 pathway and effectively reverse the PD-L1 upregulation induced by doxorubicin (DOX). So the synergistic administration of chemotherapeutic drug DOX and JQ1 is expected to increase the sensitivity of tumors to immune checkpoint therapy and jointly enhance the body's own immunity, thus effectively killing tumor cells. Therefore, a drug delivery system loaded with DOX and JQ1 was devised in this study. Methods: Polydopamine nanoparticles (PDA NPs) were synthesized through spontaneous polymerization. Under appropriate pH conditions, DOX and JQ1 were loaded onto the surface of PDA NPs, and the release of DOX and JQ1 were measured using UV-Vis or high performance liquid chromatography (HPLC). The mechanism of fabricated nanocomplex in vitro was investigated by cell uptake experiment, cell viability assays, apoptosis assays, and Western blot analysis. Finally, the tumor-bearing mouse model was used to evaluate the tumor-inhibiting efficacy and the biosafety in vivo. Results: JQ1 and DOX were successfully loaded onto PDA NPs. PDA-DOX/JQ1 NPs inhibited the growth of prostate cancer cells, reduced the expression of apoptosis related proteins and induced apoptosis in vitro. The in vivo biodistribution indicated that PDA-DOX/JQ1 NPs could accumulated at the tumor sites through the EPR effect. In tumor-bearing mice, JQ1 delivered with PDA-DOX/JQ1 NPs reduced PD-L1 expression at tumor sites, generating significant tumor suppression. Furthermore, PDA-DOX/JQ1 NPs could reduce the side effects, and produce good synergistic treatment effect in vivo. Conclusion: We have successfully prepared a multifunctional platform for synergistic prostate cancer therapy.