Advanced Prostate Cancer: Treatment Advances and Future Directions

Development and Validation of a Clinic Machine Learning Classifier for the Prediction of Risk Stratifications of Prostate Cancer Bone Metastasis Progression to Castration Resistance

Objective

To explore the predictive factors and predictive model construction for the progression of prostate cancer bone metastasis to castration resistance.

Methods

Clinical data of 286 patients diagnosed with prostate cancer with bone metastasis, initially treated with endocrine therapy, and progressing to metastatic castration resistant prostate cancer (mCRPC) were collected. By comparing the differences in various factors between different groups with fast and slow occurrence of castration-resistant prostate cancer (CRPC). Kaplan-Meier survival analysis and COX multivariate risk proportional regression model were used to compare the differences in the time to progression to CRPC in different groups. The COX multivariate risk proportional regression model was used to evaluate the impact of candidate factors on the time to progression to CRPC and establish a predictive model. The accuracy of the model was then tested using receiver operating characteristic (ROC) curves and decision curve analysis (DCA).

Results

The median time for 286 mCRPC patients to progress to CRPC was 17 (9.5-28.0) months. Multivariate analysis showed that the lowest value of PSA (PSA nadir), the time when PSA dropped to its lowest value (timePSA), and the number of BM, and LDH were independent risk factors for rapid progression to CRPC. Based on the four independent risk factors mentioned above, a prediction model was established, with the optimal prediction model being a random forest with area under curve (AUC) of 0.946[95% CI: 0.901-0.991] and 0.927[95% CI: 0.864-0.990] in the training and validation cohort, respectively.

Conclusion

After endocrine therapy, the PSA nadir, timePSA, the number of BM, and LDH are the main risk factors for rapid progression to mCRPC in patients with prostate cancer bone metastases. Establishing a CRPC prediction model is helpful for early clinical intervention decision-making.

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.

Development of a Novel Patient-Reported Outcome Measure to Assess Symptoms and Impacts of Androgen Deprivation Therapy for Advanced Prostate Cancer

INTRODUCTION

This qualitative research study was conducted to develop a novel, comprehensive, patient-reported outcome measure (PRO), the "Symptoms and Impacts of Androgen Deprivation Therapy (ADT) for Prostate Cancer" (SIADT-PC), assessing hormonal therapy-related symptoms and their impacts on men with advanced prostate cancer.

METHODS

Concept elicitation (CE) interviews were conducted among adult men with prostate cancer to evaluate their experiences with ADT. Based on key symptom and impact concepts mentioned, an initial PRO measure was developed. The draft measure was further assessed in cognitive debriefing (CD) interviews with men with prostate cancer, in which participants reviewed items, response options, and recall periods. Initial item-based psychometric analyses were conducted using interview data. The draft questionnaire was revised on the basis of participant feedback, quantitative psychometric results, and consultation with clinical experts.

RESULTS

A total of 21 participants were interviewed (CE concept elicitation, n = 12; CD cognitive debriefing, n = 17; n = 8 completed both). Mean participant age (SD) was 59.7 (8.7) years and 76.2% were white. The de novo SIADT-PC measure consists of 27 items: 11 symptoms (e.g., fatigue, hot flashes, and erectile dysfunction), 2 long-term symptoms (e.g., weight gain), 10 impacts (e.g., impacts on physical activities and relationships), and 4 related to mode of administration (i.e., injection-site reactions). Items were assessed with a 5-point verbal rating scale, with answer choices that capture frequency or severity.

CONCLUSIONS

Once fully validated, this de novo measure may be used in clinical studies and clinical practice to assess hormone therapy-related symptoms and impacts, enabling physicians to identify timely and appropriate interventions.

Preclinical Efficacy of a PSMA-Targeted Actinium-225 Conjugate (225Ac-Macropa-Pelgifatamab): A Targeted Alpha Therapy for Prostate Cancer

PURPOSE

Initially, prostate cancer responds to hormone therapy, but eventually resistance develops. Beta emitter-based prostate-specific membrane antigen (PSMA)-targeted radionuclide therapy is approved for the treatment of metastatic castration-resistant prostate cancer. Here we introduce a targeted alpha therapy (TAT) consisting of the PSMA antibody pelgifatamab covalently linked to a macropa chelator and labeled with actinium-225 and compare its efficacy and tolerability with other TATs.

EXPERIMENTAL DESIGN

The in vitro characteristics and in vivo biodistribution, antitumor efficacy, and tolerability of 225Ac-macropa-pelgifatamab (225Ac-pelgi) and other TATs were investigated in cell line- and patient-derived prostate cancer xenograft models. The antitumor efficacy of 225Ac-pelgi was also investigated in combination with the androgen receptor inhibitor darolutamide.

RESULTS

Actinium-225-labeling of 225Ac-pelgi was efficient already at room temperature. Potent in vitro cytotoxicity was seen in PSMA-expressing (LNCaP, MDA-PCa-2b, and C4-2) but not in PSMA-negative (PC-3 and DU-145) cell lines. High tumor accumulation was seen for both 225Ac-pelgi and 225Ac-DOTA-pelgi in the MDA-PCa-2b xenograft model. In the C4-2 xenograft model, 225Ac-pelgi showed enhanced antitumor efficacy with a T/Cvolume (treatment/control) ratio of 0.10 compared with 225Ac-DOTA-pelgi, 225Ac-DOTA-J591, and 227Th-HOPO-pelgifatamab (227Th-pelgi; all at 300 kBq/kg) with T/Cvolume ratios of 0.37, 0.39, and 0.33, respectively. 225Ac-pelgi was less myelosuppressive than 227Th-pelgi. 225Ac-pelgi showed dose-dependent treatment efficacy in the patient-derived KuCaP-1 model and strong combination potential with darolutamide in both cell line- (22Rv1) and patient-derived (ST1273) xenograft models.

CONCLUSIONS

These results provide a strong rationale to investigate 225Ac-pelgi in patients with prostate cancer. A clinical phase I study has been initiated (NCT06052306).

Advancements in nanomedicine: Precision delivery strategies for male pelvic malignancies - Spotlight on prostate and colorectal cancer

BACKGROUND

Pelvic malignancies consistently pose significant global health challenges, adversely affecting the well-being of the male population. It is anticipated that clinicians will continue to confront these cancers in their practice. Nanomedicine offers promising strategies that revolutionize the treatment of male pelvic malignancies by providing precise delivery methods that aim to improve the efficacy of therapeutic outcomes while minimizing side effects. Nanoparticles are designed to encapsulate therapeutic agents and selectively target cancer cells. They can also be loaded with theragnostic agents, enabling multifunctional capabilities.

OBJECTIVE

This review aims to summarize the latest nanomedicine research into clinical applications, focusing on nanotechnology-based treatment strategies for male pelvic malignancies, encompassing chemotherapy, radiotherapy, immunotherapy, and other cutting-edge therapies. The review is structured to assist physicians, particularly those with limited knowledge of biochemistry and bioengineering, in comprehending the functionalities and applications of nanomaterials.

METHODS

Multiple databases, including PubMed, the National Library of Medicine, and Embase, were utilized to locate and review recently published articles on advancements in nano-drug delivery for prostate and colorectal cancers.

CONCLUSION

Nanomedicine possesses considerable potential in improving therapeutic outcomes and reducing adverse effects for male pelvic malignancies. Through precision delivery methods, this emerging field presents innovative treatment modalities to address these challenging diseases. Nevertheless, the majority of current studies are in the preclinical phase, with a lack of sufficient evidence to fully understand the precise mechanisms of action, absence of comprehensive pharmacotoxicity profiles, and uncertainty surrounding long-term consequences.

Role of N6‑methyladenosine in the pathogenesis, diagnosis and treatment of prostate cancer (Review)

Prostate cancer (PCa) affects males of all racial and ethnic groups, and leads to higher rates of mortality in those belonging to a lower socioeconomic status due to the late detection of the disease. PCa affects middle‑aged males between the ages of 45 and 60 years, and is the highest cause of cancer‑associated mortality in Western countries. As the most abundant and common mRNA modification in higher eukaryotes, N6‑methyladenosine (m6A) is widely distributed in mammalian cells and influences various aspects of mRNA metabolism. Recent studies have found that abnormal expression levels of various m6A regulators significantly affect the development and progression of various types of cancer, including PCa. The present review discusses the influence of m6A regulatory factors on the pathogenesis and progression of PCa through mRNA modification based on the current state of research on m6A methylation modification in PCa. It is considered that the treatment of PCa with micro‑molecular drugs that target the epigenetics of the m6A regulator to correct abnormal m6A modifications is a direction for future research into current diagnostic and therapeutic approaches for PCa.

Cancer on motors: How kinesins drive prostate cancer progression?

Prostate cancer causes numerous male deaths annually. Although great progress has been made in the diagnosis and treatment of prostate cancer during the past several decades, much about this disease remains unknown, especially its pathobiology. The kinesin superfamily is a pivotal group of motor proteins, that contains a microtubule-based motor domain and features an adenosine triphosphatase activity and motility characteristics. Large-scale sequencing analyses based on clinical samples and animal models have shown that several members of the kinesin family are dysregulated in prostate cancer. Abnormal expression of kinesins could be linked to uncontrolled cell growth, inhibited apoptosis and increased metastasis ability. Additionally, kinesins may be implicated in chemotherapy resistance and escape immunologic cytotoxicity, which creates a barrier to cancer treatment. Here we cover the recent advances in understanding how kinesins may drive prostate cancer progression and how targeting their function may be a therapeutic strategy. A better understanding of kinesins in prostate cancer tumorigenesis may be pivotal for improving disease outcomes in prostate cancer patients.

A new gold(I) phosphine complex induces apoptosis in prostate cancer cells by increasing reactive oxygen species

Thioredoxin reductase (TrxR) is a pivotal regulator of redox homeostasis. It is frequently overexpressed in various cancer cells, including prostate cancer, making it a promising target for the development of anti-cancer drugs. In this study, we screened a series of newly designed complexes of gold(I) phosphine. Specifically, Compound 5 exhibited the highest cytotoxicity against prostate cancer cells and demonstrated stronger antitumor effects than commonly used drugs, such as cisplatin and auranofin. Importantly, our mechanistic study revealed that Compound 5 effectively inhibits the TrxR system in vitro. Additionally, Compound 5 promoted intracellular accumulation of reactive oxygen species (ROS), leading to mitochondrial dysfunction and irreversible apoptosis in prostate cancer cells. Our in vivo xenograft study further demonstrated that Compound 5 has excellent antitumor activity against prostate cancer cells, but does not cause severe side effects. These findings provide a promising lead Compound for the development of novel antitumor agents targeting prostate cancer and offer a valuable tool for investigating biological pathways involving TrxR and ROS modulation.

Cost-Effectiveness Analysis of Systemic Therapy for Intensification of Treatment in Metastatic Hormone-Sensitive Prostate Cancer in India

BACKGROUND AND OBJECTIVE

Androgen-deprivation therapy is the mainstay of treatment for patients with newly diagnosed metastatic hormone-sensitive prostate cancer (mHSPC). However, the intensification of treatment with either docetaxel or novel anti-androgens (abiraterone-acetate plus prednisone [AAP], enzalutamide, and apalutamide) is being recommended based on the improved clinical outcomes and quality of life among patients. This study aimed to determine the most cost-effective drug for treatment intensification for patients with mHSPC in India.

METHODS

A Markov model was developed with four health states: progression-free survival, progressive disease, best supportive care, and death. Lifetime costs and consequences were estimated for four treatment sequences: AAP-first, enzalutamide-first, apalutamide-first, and docetaxel-first. Incremental cost per quality-adjusted life-year (QALY) gained with a given treatment option was compared against the next best alternative and assessed for cost effectiveness using a willingness to pay threshold of 1 × per capita gross domestic product in India.

RESULTS

We estimated that the total lifetime cost per patient was ₹1,367,454 (US$17,487), ₹2,168,885 (US$27,735), ₹7,678,501 (US$98,190), and ₹1,358,746 (US$17,375) in the AAP-first, enzalutamide-first, apalutamide-first, and docetaxel-first treatment sequence, respectively. The mean quality-adjusted life-years lived per patient were 4.78, 5.03, 3.22, and 2.61, respectively. The AAP-first sequence incurs an incremental cost of ₹4014 (US$51) per quality-adjusted life-year gained as compared with the docetaxel-first sequence, with a 87% probability of being cost effective at the willingness-to-pay threshold of 1 × per-capita gross domestic product of India. The use of AAP-first also incurs an incremental net monetary benefit of ₹396,491 (US$5070) as compared with the docetaxel-first treatment sequence. Nearly a 48% reduction in the price of enzalutamide is required to make it a cost-effective treatment sequence as compared with AAP-first in India.

CONCLUSIONS

We concur with the inclusion of standard-dose AAP in India's publicly financed health insurance scheme for the intensification of treatment in mHSPC as it is the only cost-effective sequence among the various novel anti-androgens when compared with the docetaxel-first treatment sequence. Furthermore, a systematic reduction in the price of enzalutamide would further help to improve clinical outcomes among patients with mHSPC.

DHODH inhibition represents a therapeutic strategy and improves abiraterone treatment in castration-resistant prostate cancer

Castration-resistant prostate cancer (CRPC) is an aggressive disease with poor prognosis, and there is an urgent need for more effective therapeutic targets to address this challenge. Here, we showed that dihydroorotate dehydrogenase (DHODH), an enzyme crucial in the pyrimidine biosynthesis pathway, is a promising therapeutic target for CRPC. The transcript levels of DHODH were significantly elevated in prostate tumors and were negatively correlated with the prognosis of patients with prostate cancer. DHODH inhibition effectively suppressed CRPC progression by blocking cell cycle progression and inducing apoptosis. Notably, treatment with DHODH inhibitor BAY2402234 activated androgen biosynthesis signaling in CRPC cells. However, the combination treatment with BAY2402234 and abiraterone decreased intratumoral testosterone levels and induced apoptosis, which inhibited the growth of CWR22Rv1 xenograft tumors and patient-derived xenograft organoids. Taken together, these results establish DHODH as a key player in CRPC and as a potential therapeutic target for advanced prostate cancer.

EP300/CREBBP acetyltransferase inhibition limits steroid receptor and FOXA1 signaling in prostate cancer cells

The androgen receptor (AR) is a primary target for treating prostate cancer (PCa), forming the bedrock of its clinical management. Despite their efficacy, resistance often hampers AR-targeted therapies, necessitating new strategies against therapy-resistant PCa. These resistances involve various mechanisms, including AR splice variant overexpression and altered activities of transcription factors like the glucocorticoid receptor (GR) and FOXA1. These factors rely on common coregulators, such as EP300/CREBBP, suggesting a rationale for coregulator-targeted therapies. Our study explores EP300/CREBBP acetyltransferase inhibition's impact on steroid receptor and FOXA1 signaling in PCa cells using genome-wide techniques. Results reveal that EP300/CREBBP inhibition significantly disrupts the AR-regulated transcriptome and receptor chromatin binding by reducing the AR-gene expression. Similarly, GR's regulated transcriptome and receptor binding were hindered, not linked to reduced GR expression but to diminished FOXA1 chromatin binding, restricting GR signaling. Overall, our findings highlight how EP300/CREBBP inhibition distinctively curtails oncogenic transcription factors' signaling, suggesting the potential of coregulatory-targeted therapies in PCa.

Exploration of vitamin D metabolic activity-related biological effects and corresponding therapeutic targets in prostate cancer

BACKGROUND

Previous studies have unequivocally demonstrated that the vitamin D (VD) metabolism pathway significantly influences prognosis and sensitivity to hormone therapy in prostate cancer (PCa). However, the precise underlying mechanism remains unclear.

METHODS

We performed molecular profiling of 1045 PCa patients, leveraging genes linked to VD synthesis and VD receptors. We then identified highly variable gene modules with substantial associations with patient stratification. Subsequently, we intersected these modules with differentially expressed genes between PCa and adjacent paracancerous tissues. Following a meticulous process involving single-factor regression and LASSO regression to eliminate extraneous variables and construct a prognostic model. Within the high-risk subgroup defined by the calculated risk score, we analyzed their differences in cell infiltration, immune status, mutation landscape, and drug sensitivity. Finally, we selected Apolipoprotein E (APOE), which featured prominently in this model for further experimental exploration to evaluate its potential as a therapeutic target.

RESULTS

The prognostic model established in this study had commendable predictive efficacy. We observed diminished infiltration of various T-cell subtypes and reduced expression of co-stimulatory signals from antigen-presenting cells. Mutation analysis revealed that the high-risk cohort harbored a higher frequency of mutations in the TP53 and FOXA genes. Notably, drug sensitivity analysis suggested the heightened responsiveness of high-risk patients to molecular inhibitors targeting the Bcl-2 and MAPK pathways. Finally, our investigation also confirmed that APOE upregulates the proliferative and invasive capacity of PCa cells and concurrently enhances resistance to androgen receptor antagonist therapy.

CONCLUSION

This comprehensive study elucidated the potential mechanisms through which this metabolic pathway orchestrates the biological behavior of PCa and findings hold promise in advancing the development of combination therapies in PCa.

Targeting glutamine dependence with DRP-104 inhibits proliferation and tumor growth of castration-resistant prostate cancer

BACKGROUND

Prostate cancer (PCa) continues to be one of the leading causes of cancer deaths in men. While androgen deprivation therapy is initially effective, castration-resistant PCa (CRPC) often recurs and has limited treatment options. Our previous study identified glutamine metabolism to be critical for CRPC growth. The glutamine antagonist 6-diazo-5-oxo-l-norleucine (DON) blocks both carbon and nitrogen pathways but has dose-limiting toxicity. The prodrug DRP-104 is expected to be preferentially converted to DON in tumor cells to inhibit glutamine utilization with minimal toxicity. However, CRPC cells' susceptibility to DRP-104 remains unclear.

METHODS

Human PCa cell lines (LNCaP, LAPC4, C4-2/MDVR, PC-3, 22RV1, NCI-H660) were treated with DRP-104, and effects on proliferation and cell death were assessed. Unbiased metabolic profiling and isotope tracing evaluated the effects of DRP-104 on glutamine pathways. Efficacy of DRP-104 in vivo was evaluated in a mouse xenograft model of neuroendocrine PCa, NCI-H660.

RESULTS

DRP-104 inhibited proliferation and induced apoptosis in CRPC cell lines. Metabolite profiling showed decreases in the tricarboxylic acid cycle and nucleotide synthesis metabolites. Glutamine isotope tracing confirmed the blockade of both carbon pathway and nitrogen pathways. DRP-104 treated CRPC cells were rescued by the addition of nucleosides. DRP-104 inhibited neuroendocrine PCa xenograft growth without detectable toxicity.

CONCLUSIONS

The prodrug DRP-104 blocks glutamine carbon and nitrogen utilization, thereby inhibiting CRPC growth and inducing apoptosis. Targeting glutamine metabolism pathways with DRP-104 represents a promising therapeutic strategy for CRPC.

Nanotherapeutics for prostate cancer treatment: A comprehensive review

Prostate cancer (PCa) is the most prevalent solid organ malignancy and seriously affects male health. The adverse effects of prostate cancer therapeutics can cause secondary damage to patients. Nanotherapeutics, which have special targeting abilities and controlled therapeutic release profiles, may serve as alternative agents for PCa treatment. At present, many nanotherapeutics have been developed to treat PCa and have shown better treatment effects in animals than traditional therapeutics. Although PCa nanotherapeutics are highly attractive, few successful cases have been reported in clinical practice. To help researchers design valuable nanotherapeutics for PCa treatment and avoid useless efforts, herein, we first reviewed the strategies and challenges involved in prostate cancer treatment. Subsequently, we presented a comprehensive review of nanotherapeutics for PCa treatment, including their targeting methods, controlled release strategies, therapeutic approaches and mechanisms. Finally, we proposed the future prospects of nanotherapeutics for PCa treatment.

Real-world progression in the survival of de novo Metastatic prostate cancer over the past decade

BACKGROUND

The impact of evolving treatment strategies for metastatic prostate cancer (mPCa) on real-world survival is not well understood. We analyzed changes in mPCa survival over the past decade and discussed the potential driving factors behind these changes.

METHODS

Our study involved 43,228 mPCa patients (2004-2020) from the SEER database, divided into 4 diagnostic periods. We used a multivariate Cox proportional hazards model to evaluate diagnostic periods' influence on overall mortality (OM) and prostate cancer-specific mortality (PSM), and calculated relative median survival improvements between adjacent periods. Subgroup analyses based on age and distant metastasis sites were conducted.

RESULTS

Patients diagnosed in 2016 to 2020 experienced significantly reduced mortality risk compared to those in 2004 to 2007 (HR 0.64 for OM, HR 0.62 for CSM, both P < 0.001). The study period witnessed an absolute improvement in median overall survival (OS) and prostate cancer-specific survival (PCSS), 17 months (54.8%) and 25 months (67.6%) respectively. The most rapid relative survival improvement occurred post-2016, with a 29.7% increase in median OS and a 37.8% increase in PCSS compared to 2012 to 2015. There was a significant reduction in mortality risk throughout the study period in both age groups (age <75 and ≥75), but absolute survival gains were smaller in the older group (24 months [68.6%] vs. 8 months [32%] for OS, 36 months [90.0%] vs. 11 months [33.3%] for PCSS), with lower relative survival improvements after 2016 (37.2% vs. 17.9% for OS, 49% vs. 22.2% for PCSS). All metastasis site subgroups (except M1a) exhibited a significant reduction in mortality risk (all P < 0.001). Absolute survival improvements were 58 months (134.9%) for M1a, 16 months (50.0%) for M1b, and 17 months (54.8%) for M1c.

CONCLUSION

The survival of mPCa have significantly improved over the past decade, although the progress is slower in elderly patients. Investigating the underlying reasons for survival differences among various patient profiles can further refine mPCa treatment strategies.

Prediction of plasma ctDNA fraction and prognostic implications of liquid biopsy in advanced prostate cancer

No consensus strategies exist for prognosticating metastatic castration-resistant prostate cancer (mCRPC). Circulating tumor DNA fraction (ctDNA%) is increasingly reported by commercial and laboratory tests but its utility for risk stratification is unclear. Here, we intersect ctDNA%, treatment outcomes, and clinical characteristics across 738 plasma samples from 491 male mCRPC patients from two randomized multicentre phase II trials and a prospective province-wide blood biobanking program. ctDNA% correlates with serum and radiographic metrics of disease burden and is highest in patients with liver metastases. ctDNA% strongly predicts overall survival, progression-free survival, and treatment response independent of therapeutic context and outperformed established prognostic clinical factors. Recognizing that ctDNA-based biomarker genotyping is limited by low ctDNA% in some patients, we leverage the relationship between clinical prognostic factors and ctDNA% to develop a clinically-interpretable machine-learning tool that predicts whether a patient has sufficient ctDNA% for informative ctDNA genotyping (available online: https://www.ctDNA.org ). Our results affirm ctDNA% as an actionable tool for patient risk stratification and provide a practical framework for optimized biomarker testing.

Sinularin stabilizes FOXO3 protein to trigger prostate cancer cell intrinsic apoptosis

Sinularin, a natural product that purified from soft coral, exhibits anti-tumor effects against various human cancers. However, the mechanisms are not well understood. In this study, we demonstrated that Sinularin inhibited the viability of human prostate cancer cells in a dose-dependent manner and displayed significant cytotoxicity only at high concentration against normal prostate epithelial cell RWPE-1. Flow cytometry assay demonstrated that Sinularin induced tumor cell apoptosis. Further investigations revealed that Sinularin exerted anti-tumor activity through intrinsic apoptotic pathway along with up-regulation of pro-apoptotic protein Bax and PUMA, inhibition of anti-apoptotic protein Bcl-2, mitochondrial membrane potential collapses, and release of mitochondrial proteins. Furthermore, we illustrated that Sinularin induced cell apoptosis via up-regulating PUMA through inhibition of FOXO3 degradation by the ubiquitin-proteasome pathway. To explore how Sinularin suppress FOXO3 ubiquitin-proteasome degradation, we tested two important protein kinases AKT and ERK that regulate FOXO3 stabilization. The results revealed that Sinularin stabilized and up-regulated FOXO3 via inhibition of AKT- and ERK1/2-mediated FOXO3 phosphorylation and subsequent ubiquitin-proteasome degradation. Our findings illustrated the potential mechanisms by which Sinularin induced cell apoptosis and Sinularin may be applied as a therapeutic agent for human prostate cancer.

From PROTAC to TPD: Advances and Opportunities in Targeted Protein Degradation

PROTAC is a rapidly developing engineering technology for targeted protein degradation using the ubiquitin-proteasome system, which has promising applications for inflammatory diseases, neurodegenerative diseases, and malignant tumors. This paper gives a brief overview of the development and design principles of PROTAC, with a special focus on PROTAC-based explorations in recent years aimed at achieving controlled protein degradation and improving the bioavailability of PROTAC, as well as TPD technologies that use other pathways such as autophagy and lysosomes to achieve targeted protein degradation.

LRP5 competes for SPOP binding to enhance tumorigenesis mediated by Daxx and PD-L1 in prostate cancer

Genetic factors coordinate with environmental factors to drive the pathogenesis of prostate adenocarcinoma (PRAD). SPOP is one of the most mutated genes and LRP5 mediates lipid metabolism that is abnormally altered in PRAD. Here, we investigated the potential cross-talk between SPOP and LRP5 in PRAD. We find a negative correlation between SPOP and LRP5 proteins in PRAD. SPOP knockdown increased LRP5 protein while SPOP overexpression resulted in LRP5 reduction that was fully rescued by proteasome inhibitors. LRP5 intracellular tail has SPOP binding site and the direct interaction between LRP5 and SPOP was confirmed by Co-IP and GST-pulldown. Moreover, LRP5 competed with Daxx for SPOP-mediated degradation, establishing a dynamic balance among SPOP, LRP5 and Daxx. Overexpression of LRP5 tail could shift this balance to enhance Daxx-mediated transcriptional inhibition, and inhibit T cell activity in a co-culture system. Further, we generated human and mouse prostate cancer cell lines expressing SPOP variants (F133V, A227V, R368H). SPOP-F133V and SPOP-A227V have specific effects in up-regulating the protein levels of PD-1 and PD-L1. Consistently, SPOP-F133V and SPOP-A227V show robust inhibitory effects on T cells compared to WT SPOP in co-culture. This is further supported by the mouse syngeneic model showing that SPOP-F133V and SPOP-A227V enhance tumorigenesis of prostate cancer in in-vivo condition. Taken together, our study provides evidence that SPOP-LRP5 crosstalk plays an essential role, and the genetic variants of SPOP differentially modulate the expression and activity of immune checkpoints in prostate cancer.

Comprehensive Review on Recent Strategies for Management of Prostate Cancer: Therapeutic Targets and SAR

Prostate cancer is a disease that is affecting a large population worldwide. Androgen deprivation therapy (ADT) has become a foundation for the treatment of advanced prostate cancer, as used in most clinical settings from neo-adjuvant to metastatic stage. In spite of the success of ADT in managing the disease in the majority of men, hormonal manipulation fails eventually. New molecules are developed for patients with various hormone-refractory diseases. Advancements in molecular oncology have increased understanding of numerous cellular mechanisms which control cell death in the prostate and these insights can lead to the development of more efficacious and tolerable therapies for carcinoma of the prostate. This review is focused on numerous therapies that might be a boon for prostate therapy like signaling inhibitors, vaccines, and inhibitors of androgen receptors. Along with these, various bioactive molecules and their derivatives are highlighted, which act as potential antiprostate cancer agents. This article also emphasized the recent advances in the field of medicinal chemistry of prostate cancer agents.

Targeting tumor and bone microenvironment: Novel therapeutic opportunities for castration-resistant prostate cancer patients with bone metastasis

Despite standard hormonal therapy that targets the androgen receptor (AR) attenuates prostate cancer (PCa) effectively in the initial stage, the tumor ultimately converts to castration-resistant prostate cancer (CRPC), and the acquired resistance is still a great challenge for the management of advanced prostate cancer patients. The tumor microenvironment (TME) consists of multiple cellular and noncellular agents is well known as a vital role during the development and progression of CRPC by establishing communication between TME and tumor cells. Additionally, as primary prostate cancer progresses towards metastasis, and CRPC always experiences bone metastasis, the TME is conducive to the spread of tumors to the distant sits, particularly in bone. In addition, the bone microenvironment (BME) is also closely related to the survival, growth and colonization of metastatic tumor cells. The present review summarized the recent studies which mainly focused on the role of TME or BME in the CRPC patients with bone metastasis, and discussed the underlying mechanisms, as well as the potential therapeutic values of targeting TME and BME in the management of metastatic CRPC patients.

Molecular heterogeneity in prostate cancer and the role of targeted therapy

Data collected from large-scale studies has shown that the incidence of prostate cancer globally is on the rise, which could be attributed to an overall increase in lifespan. So, the question is how has modern science with all its new technologies and clinical breakthroughs mitigated or managed this disease? The answer is not a simple one as prostate cancer exhibits various subtypes, each with its unique characteristics or signatures which creates challenges in treatment. To understand the complexity of prostate cancer these signatures must be deciphered. Molecular studies of prostate cancer samples have identified certain genetic and epigenetic alterations, which are instrumental in tumorigenesis. Some of these candidates include the androgen receptor (AR), various oncogenes, tumor suppressor genes, and the tumor microenvironment, which serve as major drivers that lead to cancer progression. These aberrant genes and their products can give an insight into prostate cancer development and progression by acting as potent markers to guide future therapeutic approaches. Thus, understanding the complexity of prostate cancer is crucial for targeting specific markers and tailoring treatments accordingly.

Examining Exclusion Criteria in Advanced Prostate Cancer Clinical Trials: An Assessment of recommendations From the American Society Of Clinical Oncology and Friends of Cancer Research

PURPOSE

Eligibility criteria illustrate the characteristics of the study population and promote the safety of participants. However, overreliance on restrictive eligibility criteria may limit the generalizability of outcomes. As a result, the American Society of Clinical Oncology (ASCO) and Friends of Cancer Research (Friends) issued statements to curtail these challenges. In this study, we aimed to assess restrictiveness in eligibility criteria across advanced prostate cancer clinical trials.

MATERIALS AND METHODS

We identified all phase I, II, and III advanced prostate cancer clinical trials between June 30, 2012, and June 30, 2022, through Clinicaltrials.gov. We evaluated whether a clinical trial excluded, conditionally included, or did not report 4 common criteria: brain metastases, prior or concurrent malignancies, HIV infection, and hepatitis B virus (HBV)/hepatitis C virus (HCV) infection. Performance status (PS) criteria were recorded based on the Eastern Cooperative Oncology Group (ECOG) scale.

RESULTS

Out of 699 clinical trials within our search strategy, 265 (37.9%) trials possessed all the required data and were included in our analysis. The most common excluded condition of our interest was brain metastases (60.8%), followed by HIV positivity (46.4%), HBV/HCV positivity (46.0%), and concurrent malignancies (15.5%). Additionally, 50.9% of clinical trials only included patients with ECOG PS 0 to 1. HIV and HBV/HCV infection were exclusion criteria of 22 (80.8%) and 19 (73.1%) immunotherapy trials, respectively.

CONCLUSION

Patients with brain metastases, prior or concurrent malignancies, HIV infection, HBV/HCV infection, or low-functioning PS were overly restricted from participating in advanced prostate clinical trials. Advocating for broader criteria may ameliorate generalizability.

LMNB1 targets FOXD1 to promote progression of prostate cancer

Forkhead box D1 (FOXD1) expression is upregulated in various types of human cancer. To the best of our knowledge, the roles of FOXD1 in prostate cancer (PC) remain largely unknown. The Cancer Genome Atlas dataset was used for the bioinformatics analysis of FOXD1 in PC. FOXD1 expression levels in normal immortalized human prostate epithelial cells (RWPE-1) and prostate cancer cells were detected by reverse transcription-quantitative PCR. PC cell viability was detected using Cell Counting Kit-8 assay. Transwell assays were performed to assess the migration and invasion of PC cells. Luciferase reporter gene assay was used to validate the association between FOXD1 and lamin (LMN)B1. LMNB1 is an important part of the cytoskeleton, which serves an important role in the process of tumor occurrence and development, regulating apoptosis and DNA repair. FOXD1 expression was upregulated in PC tissues, with its high expression being associated with clinical stage and survival in PC. Knockdown of FOXD1 inhibited viability, migration and invasion of PC cells. FOXD1 positively regulated LMNB1 expression. The effect of FOXD1 knockdown on PC cells was reversed by LMNB1 overexpression. In conclusion, FOXD1, positively regulated by LMNB1, served as an oncogene in PC and may be a potential biomarker and treatment target for PC.

Molecular pathogenesis, mechanism and therapy of Cav1 in prostate cancer

Prostate cancer is the second incidence of malignant tumors in men worldwide. Its incidence and mortality are increasing year by year. Enhanced expression of Cav1 in prostate cancer has been linked to both proliferation and metastasis of cancer cells, influencing disease progression. Dysregulation of the Cav1 gene shows a notable association with prostate cancer. Nevertheless, there is no systematic review to report about molecular signal mechanism of Cav1 and drug treatment in prostate cancer. This article reviews the structure, physiological and pathological functions of Cav1, the pathogenic signaling pathways involved in prostate cancer, and the current drug treatment of prostate cancer. Cav1 mainly affects the occurrence of prostate cancer through AKT/mTOR, H-RAS/PLCε, CD147/MMPs and other pathways, as well as substance metabolism including lipid metabolism and aerobic glycolysis. Baicalein, simvastatin, triptolide and other drugs can effectively inhibit the growth of prostate cancer. As a biomarker of prostate cancer, Cav1 may provide a potential therapeutic target for the treatment of prostate cancer.

Antitumor activity of alkylphospholipid edelfosine in prostate cancer models and endoplasmic reticulum targeting

Prostate cancer is the second most frequent cancer and the fifth leading cause of cancer death among men worldwide. While the five-year survival in local and regional prostate cancer is higher than 99%, it falls to about 28% in advanced metastatic prostate cancer. The ether lipid edelfosine is considered the prototype of a family of promising antitumor drugs collectively named as alkylphospholipid analogs. Here, we found that edelfosine was the most potent alkylphospholipid analog in inducing apoptosis in three different human prostate cancer cell lines (LNCaP, PC3, and DU145) with distinct androgen dependency, and differing in tumor suppressor phosphatase and tensin homolog (PTEN) and p53 status. Edelfosine accumulated in the endoplasmic reticulum of prostate cancer cells, leading to endoplasmic reticulum stress and cell death in the three prostate cancer cells. Inhibition of autophagy potentiated the pro-apoptotic activity of edelfosine in LNCaP and PC3 cells, where autophagy was induced as a survival response. Edelfosine induced a slight and transient inhibition of AKT in PTEN-negative LNCaP and PC3 cells, but not in PTEN-positive DU145 cells. Daily oral administration of edelfosine in murine prostate restricted AKT kinase transgenic mice, expressing active AKT in a prostate-specific manner, and in a DU145 xenograft mouse model resulted in significant tumor regression and apoptosis in tumor cells. Taken together, these results show a significant in vitro and in vivo antitumor activity of edelfosine against prostate cancer, and highlight the endoplasmic reticulum as a novel and promising therapeutic target in prostate cancer.

FADS2 function at the major cancer hotspot 11q13 locus alters fatty acid metabolism in cancer

Dysregulation of fatty acid metabolism and de novo lipogenesis is a key driver of several cancer types through highly unsaturated fatty acid (HUFA) signaling precursors such as arachidonic acid. The human chromosome 11q13 locus has long been established as the most frequently amplified in a variety of human cancers. The fatty acid desaturase genes (FADS1, FADS2 and FADS3) responsible for HUFA biosynthesis localize to the 11q12-13.1 region. FADS2 activity is promiscuous, catalyzing biosynthesis of several unsaturated fatty acids by Δ6, Δ8, and Δ4 desaturation. Our main aim here is to review known and putative consequences of FADS2 dysregulation due to effects on the 11q13 locus potentially driving various cancer types. FADS2 silencing causes synthesis of sciadonic acid (5Z,11Z,14Z-20:3) in MCF7 cells and breast cancer in vivo. 5Z,11Z,14Z-20:3 is structurally identical to arachidonic acid (5Z,8Z,11Z,14Z-20:4) except it lacks the internal Δ8 double bond required for prostaglandin and leukotriene synthesis, among other eicosanoids. Palmitic acid has substrate specificity for both SCD and FADS2. Melanoma, prostate, liver and lung cancer cells insensitive to SCD inhibition show increased FADS2 activity and sapienic acid biosynthesis. Elevated serum mead acid levels found in hepatocellular carcinoma patients suggest an unsatisfied demand for arachidonic acid. FADS2 circular RNAs are at high levels in colorectal and lung cancer tissues. FADS2 circular RNAs are associated with shorter overall survival in colorectal cancer patients. The evidence thusfar supports an effort for future research on the role of FADS2 as a tumor suppressor in a range of neoplastic disorders.

Analysis of genetic biomarkers, polymorphisms in ADME-related genes and their impact on pharmacotherapy for prostate cancer

Prostate cancer (PCa) is a non-cutaneous malignancy in males with wide variation in incidence rates across the globe. It is the second most reported cause of cancer death. Its etiology may have been linked to genetic polymorphisms, which are not only dominating cause of malignancy casualties but also exerts significant effects on pharmacotherapy outcomes. Although many therapeutic options are available, but suitable candidates identified by useful biomarkers can exhibit maximum therapeutic efficacy. The single-nucleotide polymorphisms (SNPs) reported in androgen receptor signaling genes influence the effectiveness of androgen receptor pathway inhibitors and androgen deprivation therapy. Furthermore, SNPs located in genes involved in transport, drug metabolism, and efflux pumps also influence the efficacy of pharmacotherapy. Hence, SNPs biomarkers provide the basis for individualized pharmacotherapy. The pharmacotherapeutic options for PCa include hormonal therapy, chemotherapy (Docetaxel, Mitoxantrone, Cabazitaxel, and Estramustine, etc.), and radiotherapy. Here, we overview the impact of SNPs reported in various genes on the pharmacotherapy for PCa and evaluate current genetic biomarkers with an emphasis on early diagnosis and individualized treatment strategy in PCa.

Advances in the treatment of metastatic prostate cancer

The field of metastatic prostate cancer (mPCa) has seen unprecedented therapeutic advances in the past decade. In the past 2 years, recent approvals include the triplet therapy regimens of androgen deprivation therapy (ADT), docetaxel, and an androgen receptor (AR) pathway inhibitor (ARPI) in the castration-sensitive setting and lutetium-177 vipivotide tetraxetan (177Lu-PSMA-617) and the combination of poly(ADP) ribose polymerase (PARP) inhibitors (PARPis) and ARPIs in the castration-resistant setting. With many agents currently undergoing investigation in registration trials, the therapeutic armamentarium will expand rapidly, making treatment selection and sequencing challenging. Herein, we review the landmark clinical trials ongoing or reported in the past 2 years, discuss the optimal approach to treatment selection, and provide insight into future directions.

Characterization of allosteric modulators that disrupt androgen receptor co-activator protein-protein interactions to alter transactivation-Drug leads for metastatic castration resistant prostate cancer

Three series of compounds were prioritized from a high content screening campaign that identified molecules that blocked dihydrotestosterone (DHT) induced formation of Androgen Receptor (AR) protein-protein interactions (PPIs) with the Transcriptional Intermediary Factor 2 (TIF2) coactivator and also disrupted preformed AR-TIF2 PPI complexes; the hydrobenzo-oxazepins (S1), thiadiazol-5-piperidine-carboxamides (S2), and phenyl-methyl-indoles (S3). Compounds from these series inhibited AR PPIs with TIF2 and SRC-1, another p160 coactivator, in mammalian 2-hybrid assays and blocked transcriptional activation in reporter assays driven by full length AR or AR-V7 splice variants. Compounds inhibited the growth of five prostate cancer cell lines, with many exhibiting differential cytotoxicity towards AR positive cell lines. Representative compounds from the 3 series substantially reduced both endogenous and DHT-enhanced expression and secretion of the prostate specific antigen (PSA) cancer biomarker in the C4-2 castration resistant prostate cancer (CRPC) cell line. The comparatively weak activities of series compounds in the H3-DHT and/or TIF2 box 3 LXXLL-peptide binding assays to the recombinant ligand binding domain of AR suggest that direct antagonism at the orthosteric ligand binding site or AF-2 surface respectively are unlikely mechanisms of action. Cellular enhanced thermal stability assays (CETSA) indicated that compounds engaged AR and reduced the maximum efficacy and right shifted the EC50 of DHT-enhanced AR thermal stabilization consistent with the effects of negative allosteric modulators. Molecular docking of potent representative hits from each series to AR structures suggest that S1-1 and S2-6 engage a novel binding pocket (BP-1) adjacent to the orthosteric ligand binding site, while S3-11 occupies the AR binding function 3 (BF-3) allosteric pocket. Hit binding poses indicate spaces and residues adjacent to the BP-1 and BF-3 pockets that will be exploited in future medicinal chemistry optimization studies. Small molecule allosteric modulators that prevent/disrupt AR PPIs with coactivators like TIF2 to alter transcriptional activation in the presence of orthosteric agonists might evade the resistance mechanisms to existing prostate cancer drugs and provide novel starting points for medicinal chemistry lead optimization and future development into therapies for metastatic CRPC.

The second docetaxel rechallenge for metastatic castration-resistant prostate cancer: a case report

Background

Docetaxel combined with prednisone plus androgen deprivation therapy (ADT) is the preferred treatment option for metastatic hormone-sensitive prostate cancer (mHSPC) or metastatic castration-resistant prostate cancer (mCRPC). With the development of next-generation hormonal agents (NHAs) and poly (ADP-ribose) polymerase (PARP) inhibitors, more aggressive first-line or later-line treatment strategies have been added to the treatment of mHSPC and mCRPC. However, docetaxel rechallenge (DR) has special clinical significance in patients with "docetaxel-sensitive" prostate cancer. There are no reports on the efficacy and safety of the second DR in mCRPC patients.

Case presentation

We report one patient diagnosed with mCRPC who showed progression-free survival (PFS) and overall survival (OS) benefits and safety and good lower urinary tract function after the second DR.

Conclusion

The second DR as a potential alternative later-line treatment strategy should be considered for patients with mCRPC who worry about the high economic burden of multigene molecular testing and PARP inhibitors as well as repeated prostate needle biopsy.

New insights into molecular signaling pathways and current advancements in prostate cancer diagnostics & therapeutics

Prostate adenocarcinoma accounts for more than 20% of deaths among males due to cancer. It is the fifth-leading cancer diagnosed in males across the globe. The mortality rate is quite high due to prostate cancer. Despite the fact that advancements in diagnostics and therapeutics have been made, there is a lack of effective drugs. Metabolic pathways are altered due to the triggering of androgen receptor (AR) signaling pathways, and elevated levels of dihydrotestosterone are produced due to defects in AR signaling that accelerate the growth of prostate cancer cells. Further, PI3K/AKT/mTOR pathways interact with AR signaling pathway and act as precursors to promote prostate cancer. Prostate cancer therapy has been classified into luminal A, luminal B, and basal subtypes. Therapeutic drugs inhibiting dihydrotestosterone and PI3K have shown to give promising results to combat prostate cancer. Many second-generation Androgen receptor signaling antagonists are given either as single agent or with the combination of other drugs. In order to develop a cure for metastasized prostate cancer cells, Androgen deprivation therapy (ADT) is applied by using surgical or chemical methods. In many cases, Prostatectomy or local radiotherapy are used to control metastasized prostate cancer. However, it has been observed that after 1.5 years to 2 years of Prostatectomy or castration, there is reoccurrence of prostate cancer and high incidence of castration resistant prostate cancer is seen in population undergone ADT. It has been observed that Androgen derivation therapy combined with drugs like abiraterone acetate or docetaxel improve overall survival rate in metastatic hormone sensitive prostate cancer (mHSPC) patients. Scientific investigations have revealed that drugs inhibiting poly ADP Ribose polymerase (PARP) are showing promising results in clinical trials in the prostate cancer population with mCRPC and DNA repair abnormalities. Recently, RISUG adv (reversible inhibition of sperm under guidance) has shown significant results against prostate cancer cell lines and MTT assay has validated substantial effects of this drug against PC3 cell lines. Current review paper highlights the advancements in prostate cancer therapeutics and new drug molecules against prostate cancer. It will provide detailed insights on the signaling pathways which need to be targeted to combat metastasized prostate cancer and castration resistant prostate cancer.

Dissecting Microbiome-Derived SCFAs in Prostate Cancer: Analyzing Gut Microbiota, Racial Disparities, and Epigenetic Mechanisms

Prostate cancer (PCa) continues to be the most diagnosed cancer and the second primary cause of fatalities in men globally. There is an abundance of scientific evidence suggesting that the human microbiome, together with its metabolites, plays a crucial role in carcinogenesis and has a significant impact on the efficacy of anticancer interventions in solid and hematological cancers. These anticancer interventions include chemotherapy, immune checkpoint inhibitors, and targeted therapies. Furthermore, the microbiome can influence systemic and local immune responses using numerous metabolites such as short-chain fatty acids (SCFAs). Despite the lack of scientific data in terms of the role of SCFAs in PCa pathogenesis, recent studies show that SCFAs have a profound impact on PCa progression. Several studies have reported racial/ethnic disparities in terms of bacterial content in the gut microbiome and SCFA composition. These studies explored microbiome and SCFA racial/ethnic disparities in cancers such as colorectal, colon, cervical, breast, and endometrial cancer. Notably, there are currently no published studies exploring microbiome/SCFA composition racial disparities and their role in PCa carcinogenesis. This review discusses the potential role of the microbiome in PCa development and progression. The involvement of microbiome-derived SCFAs in facilitating PCa carcinogenesis and their effect on PCa therapeutic response, particularly immunotherapy, are discussed. Racial/ethnic differences in microbiome composition and SCFA content in various cancers are also discussed. Lastly, the effects of SCFAs on PCa progression via epigenetic modifications is also discussed.

Modified Citrus Pectin Treatment in Non-Metastatic Biochemically Relapsed Prostate Cancer: Long-Term Results of a Prospective Phase II Study

The optimal therapy for patients with non-metastatic biochemically relapsed prostate cancer (BRPC-M0) after local therapy is elusive. Thus, the evaluation of new non-toxic compounds in BRPC-M0 patients is warranted. PectaSol®-Modified citrus pectin (P-MCP) is a food supplement categorized as GRAS (Generally Recognized As Safe) by the FDA. It is a competitive inhibitor of the galectin-3 protein, which is involved in cancer pathogenesis. In an early report of the present phase 2 study, P-MCP treatment for 6 months led to prostate-specific antigen doubling time (PSADT) improvement in 75% of patients with BRPC-M0. Herein, we report the second long-term treatment phase of an additional 12 months of P-MCP therapy (4.8 g × 3/day orally) in patients without disease progression after the initial 6 months of therapy. Of the 46 patients that entered the second treatment phase, 7 patients withdrew consent and decided to continue therapy out of pocket, and 39 initiated the second treatment phase. After a total of 18 months of P-MCP treatment, 85% (n = 33) had a durable long-term response, with 62% (n = 24) showing decreased/stable PSA, 90% (n = 35) PSADT improvement, and all with negative scans. No patient had grade 3/4 toxicity. In conclusion, P-MCP may have long-term durable efficacy and is safe in BRPC-M0.

Improving Overall Survival and Quality of Life in Patients with Prostate Cancer and Neuroendocrine Tumors Using 177Lu-iPSMA and 177Lu-DOTATOC: Experience after 905 Treatment Doses

¹⁷⁷Lu-iPSMA is a novel radioligand developed at ININ-Mexico with a high affinity for the PSMA protein heavily expressed in cancer cells of approximately 95% of patients with metastatic castration-resistant prostate cancer (mCRPC). ¹⁷⁷Lu-DOTATOC is a patent-free radioligand, molecularly recognized by somatostatin receptors (SSTR-2) overexpressed in cancer cells of about 80% of patients with metastatic gastroenteropancreatic neuroendocrine tumors (GEP-NET). This translational research aimed to determine the efficacy and safety of ¹⁷⁷Lu-iPSMA and ¹⁷⁷Lu-DOTATOC developed as GMP pharmaceutical formulations for treating progressive and advanced mCRPC and NET. One hundred and forty-five patients with mCRPC and one hundred and eighty-seven subjects with progressive NET (83% GEP-NET and 17% other NET), treated with ¹⁷⁷Lu-iPSMA and ¹⁷⁷Lu-DOTATOC, respectively, were evaluated. Patients received a mean dose of 7.4 GBq per administration of ¹⁷⁷Lu-iPSMA (range 1-5 administrations; 394 treatment doses) or ¹⁷⁷Lu-DOTATOC (range 2-8 administrations; 511 treatment doses) at intervals of 1.5-2.5 months. Efficacy was assessed by SPECT/CT or PET/CT. Results were stratified by primary tumor origin and number of doses administered. Patients with mCRPC showed overall survival (OS) of 21.7 months with decreased radiotracer tumor uptake (SUV) and PSA level in 80% and 73% of patients, respectively. In addition, a significant reduction in pain (numerical scale from 10-7 to 3-1) was observed in 88% of patients with bone metastases between one and two weeks after the second injection. In the GEP-NET population, the median progression-free survival was 34.7 months, with an OS of >44.2 months. The treatments were well tolerated. Only ten patients experienced grade ≥ 3 myelosuppression (3% of all patients). The observed safety profiles and favorable therapeutic responses demonstrated the potential of ¹⁷⁷Lu-iPSMA and ¹⁷⁷Lu-DOTATOC to improve overall survival and quality of life in patients with progressive and advanced mCRPC and NET.

Integrative analysis of the ST6GALNAC family identifies GATA2-upregulated ST6GALNAC5 as an adverse prognostic biomarker promoting prostate cancer cell invasion

BACKGROUND

ST6GALNAC family members function as sialyltransferases and have been implicated in cancer progression. However, their aberrant expression levels, prognostic values and specific roles in metastatic prostate cancer (PCa) remain largely unclear.

METHODS

Two independent public datasets (TCGA-PRAD and GSE21032), containing 648 PCa samples in total, were employed to comprehensively examine the mRNA expression changes of ST6GALNAC family members in PCa, as well as their associations with clinicopathological parameters and prognosis. The dysregulation of ST6GALNAC5 was further validated in a mouse PCa model and human PCa samples from our cohort (n = 64) by immunohistochemistry (IHC). Gene Set Enrichment Analysis, Gene Ontology, Kyoto Encyclopedia of Genes and Genomes and drug sensitivity analyses were performed to enrich the biological processes most related to ST6GALNAC5. Sulforhodamine B, transwell, luciferase reporter and chromatin immunoprecipitation (ChIP) assays were used to examine the PCa cell proliferation, invasion and transcriptional regulation, respectively.

RESULTS

Systematical investigation of six ST6GALNAC family members in public datasets revealed that ST6GALNAC5 was the only gene consistently and significantly upregulated in metastatic PCa, and ST6GALNAC5 overexpression was also positively associated with Gleason score and predicted poor prognosis in PCa patients. IHC results showed that (1) ST6GALNAC5 protein expression was increased in prostatic intraepithelial neoplasia and further elevated in PCa from a PbCre;Pten^F/F mouse model; (2) overexpressed ST6GALNAC5 protein was confirmed in human PCa samples comparing with benign prostatic hyperplasia samples from our cohort (p < 0.001); (3) ST6GALNAC5 overexpression was significantly correlated with perineural invasion of PCa. Moreover, we first found transcription factor GATA2 positively and directly regulated ST6GALNAC5 expression at transcriptional level. ST6GALNAC5 overexpression could partially reverse GATA2-depletion-induced inhibition of PCa cell invasion. The GATA2-ST6GALNAC5 signature exhibited better prediction on the poor prognosis in PCa patients than GATA2 or ST6GALNAC5 alone.

CONCLUSIONS

Our results indicated that GATA2-upregulated ST6GALNAC5 might serve as an adverse prognostic biomarker promoting prostate cancer cell invasion.

MiR-138-5p inhibits prostate cancer cell proliferation and chemoresistance by targeting APOBEC3B

Docetaxel is one of the most commonly used drugs in prostate cancer (PCa) chemotherapy, but its therapeutic effect in PCa is usually limited due to its drug resistance. APOBEC3B is a DNA cytosine deaminase that can alter biological processes, including chemoresistance. APOBEC3B is upregulated in various cancers. However, the biological function and underlying regulation of APOBEC3B in PCa remain unclear. In this study, we explored the role of APOBEC3B in PCa chemoresistance and the molecular mechanism of its dysregulated expression. Our results revealed that APOBEC3B was upregulated in PCa docetaxel-resistant cells, while its knockdown significantly repressed cell proliferation and docetaxel resistance of PCa cells. Bioinformatics and luciferase report analysis showed that miR-138-5p targeted APOBEC3B. In addition, miR-138-5p overexpression impeded cell proliferation and docetaxel resistance in PCa, while miR-138-5p inhibitors reversed this process. Further studies showed that upregulation of APOBEC3B expression in docetaxel-resistant cells overexpressing miR-138-5p could desensitize PCa cells to docetaxel treatment. Taken together, miR-138-5p regulates PCa cell proliferation and chemoresistance by targeting the 3'-UTR of APOBEC3B, which may provide novel insights and therapeutic targets for the treatment of PCa.

Uncommon Manifestation of Oligometastatic Prostate Cancer: Sister Mary Joseph Nodule

ABSTRACT

A 76-year-old man with a history of prostate cancer diagnosed in 2008 developed biochemical recurrence in 2010 and started intermittent androgen deprivation therapy. In 2021, due to rising prostate-specific antigen, an 18 F-piflufolastat PSMA PET/CT was performed. It showed a radiotracer-avid sclerotic lesion in the right iliac bone and an indeterminate radiotracer-avid nodule in the umbilical region, demonstrating progressive enlargement and increased uptake on subsequent imaging. Pathologic analysis of the umbilical nodule revealed metastatic prostate cancer-a finding eponymically referred to as a Sister Mary Joseph nodule.

A kinome-wide CRISPR screen identifies CK1α as a target to overcome enzalutamide resistance of prostate cancer

Enzalutamide (ENZA), a second-generation androgen receptor antagonist, has significantly increased progression-free and overall survival of patients with metastatic prostate cancer (PCa). However, resistance remains a prominent obstacle in treatment. Utilizing a kinome-wide CRISPR-Cas9 knockout screen, we identified casein kinase 1α (CK1α) as a therapeutic target to overcome ENZA resistance. Depletion or pharmacologic inhibition of CK1α enhanced ENZA efficacy in ENZA-resistant cells and patient-derived xenografts. Mechanistically, CK1α phosphorylates the serine residue S1270 and modulates the protein abundance of ataxia telangiectasia mutated (ATM), a primary initiator of DNA double-strand break (DSB)-response signaling, which is compromised in ENZA-resistant cells and patients. Inhibition of CK1α stabilizes ATM, resulting in the restoration of DSB signaling, and thus increases ENZA-induced cell death and growth arrest. Our study details a therapeutic approach for ENZA-resistant PCa and characterizes a particular perspective for the function of CK1α in the regulation of DNA-damage response.

Pharmacokinetics and Bioequivalence of Abiraterone Acetate Tablets in Healthy Chinese Volunteers: An Open, Randomized, Single-Dose, Three-Period, Three-Sequence Crossover Study

BACKGROUND AND OBJECTIVE

Abiraterone acetate tablet is an inhibitor of androgen synthesis, primarily for the treatment of metastatic castration-resistant prostate cancer (mCRPC). This study evaluated the bioequivalence and pharmacokinetics of the reference and test formulations of abiraterone acetate tablets in healthy Chinese volunteers.

METHODS

A single-center, open, single-dose, randomized, three-period, three-sequence, semi-repeat (only repeated reference formulations), and reference formulation-corrected fasting reference-scaled average bioequivalence test was conducted in 36 healthy volunteers included in this study. Volunteers were randomly assigned to one of three groups in a 1:1:1 ratio. There was a minimum 7-day washout period between each dose. Blood samples were collected at prescribed time intervals, the plasma concentration of abiraterone acetate tablets was determined by liquid chromatography-tandem mass spectrometry, and adverse events were recorded.

RESULTS

Under fasting conditions, the maximum plasma concentration (C_max) was 27.02 ± 14.21 ng/mL, area under the concentration-time curve from time zero to time t (AUC_t) was 125.30 ± 82.41 h·ng/mL, and AUC from time zero to infinity (AUC_∞) was 133.70 ± 83.99 h·ng/mL. The 90% confidence intervals (CIs) of the geometric mean ratio (GMR) of AUC_t and AUC_∞ were in the range of 0.8000-1.2500, and the coefficient of variation (CV_WR) of C_max was more than 30%. The Critbound result was - 0.0522, and the GMR was between 0.8000 and 1.2500.

CONCLUSION

Both test and reference formulations of abiraterone acetate tablets were bioequivalent in healthy Chinese subjects under fasting conditions.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT04863105, registered 26 April 2021-retrospectively registered ( https://register.

CLINICALTRIALS

gov/prs/app/action/SelectProtocol?sid=S000ARAA&selectaction=Edit&uid=U00050YQ&ts=2&cx=-vbtjri.

Efficacy and safety of apalutamide in patients with metastatic castration-resistant prostate cancer (GENESIS): protocol for a multicentre, open-label, single-arm clinical trial

INTRODUCTION

This is a multicentre, open-label, single-arm clinical trial to evaluate the efficacy and safety of apalutamide in patients with metastatic castration-resistant prostate cancer.

METHODS AND ANALYSIS

The trial will be performed at 4 university hospitals and 14 city hospitals in Japan. The target number of patients will be 110. The patients will be orally administered 240 mg apalutamide once daily during the treatment period. The primary outcome is the prostate-specific antigen (PSA) response rate. PSA response is defined as ≥50% decline from baseline at 12 weeks. Secondary outcomes are time to PSA progression, progression-free survival, overall survival, progression-free survival during second therapy, ≥50% decline in PSA from baseline at 24 and 48 weeks, ≥90% decline in PSA from baseline or lower PSA detection sensitivity after the initial dose at 12, 24 and 48 weeks, PSA maximal changes, accumulated PSA response from screening to 24 and 48 weeks, and grade 3 or 4 adverse events according to the Common Terminology Criteria for Adverse Events version 4.0.

ETHICS AND DISSEMINATION

This study has been approved by the Certified Research Review Board of Kobe University (No. CRB5180009). All participants will be required to provide written informed consent. Findings will be disseminated through scientific and professional conferences and peer-reviewed journal publications. The datasets generated during the study will be available from the corresponding author on reasonable request.

TRIAL REGISTRATION NUMBER

jRCTs051220077.

KIF14 mediates cabazitaxel-docetaxel cross-resistance in advanced prostate cancer by promoting AKT phosphorylation

Docetaxel is a first-line chemotherapy drug for castration-resistant prostate cancer (CRPC); yet, some CRPC patients develop docetaxel drug resistance. Cabazitaxel is approved in the post-docetaxel treatment setting. However, recent studies suggested cross-resistance between the development of drug resistance and current treatments. In this study, we used docetaxel-resistant cell lines DU145/DTX50 and PC-3/DTX30 to measure the responses to cabazitaxel. Our findings demonstrated that docetaxel resistance could lead to cross-resistance to cabazitaxel. After docetaxel-resistant cells were treated with cabazitaxel, transcriptome analysis was performed, and the results were analyzed in combination with survival analysis and correlation analysis with Gleason score to screen the cross-resistance genes. The continuously increased expression of kinesin family member 14 (KIF14) was identified as the main cause of cross-resistance to cabazitaxel in docetaxel-resistant cells. Silencing the expression of KIF14 could restore the sensitivity of resistant PCa cells to docetaxel and cabazitaxel, attenuate proliferation and promote apoptosis of the resistant PCa cells. Notably, the depressed expression of KIF14 inhibited the phosphorylation of Akt located downstream. In summary, KIF14 mediates the cross-resistance between docetaxel and cabazitaxel, and targeting KIF14 could be an effective measurement for reversing docetaxel or cabazitaxel chemotherapy failure or enhancing the anti-tumor effects of docetaxel or cabazitaxel.

ARPC5 is transcriptionally activated by KLF4, and promotes cell migration and invasion in prostate cancer via up-regulating ADAM17 : ARPC5 serves as an oncogene in prostate cancer

BACKGROUND

Prostate cancer (PCa) is one of the most common cancers in men worldwide. Actin-related protein 2/3 complex subunit 5 (ARPC5) has been validated as a critical regulator in several kinds of human tumors. However, whether ARPC5 is implicated in PCa progression remains largely unknown.

METHODS

PCa specimens and PCa cell lines were obtained for detecting gene expressions using western blot and quantitative reverse transcriptase PCR (qRT-PCR). PCa cells transfected with ARPC5 shRNA or a disintegrin and metalloprotease 17 (ADAM17) overexpressed plasmids were harvested for assessing cell proliferation, migration and invasion by using cell counting kit-8 (CCK-8), colony formation and transwell assays, respectively. The interaction relationship between molecules was testified with chromatin immunoprecipitation and luciferase reporter assay. Xenograft mice model was conducted for confirming the role of ARPC5/ADAM17 axis in vivo.

RESULTS

Upregulated ARPC5 was observed in PCa tissues and cells, as well as forecasted poor prognosis of PCa patients. Depletion of ARPC5 inhibited PCa cell proliferation, migration and invasion. Krüppel-like factor 4 (KLF4) was identified to be a transcriptional activator of ARPC5 via binding with its promoter region. Furthermore, ADAM17 served as a downstream effector of ARPC5. ADAM17 overexpression overturned ARPC5 knockdown-induced repressive impacts on PCa progression in vitro and in vivo.

CONCLUSION

Collectively, ARPC5 was activated by KLF4 and upregulated ADAM17 to promote PCa progression, which might act as a promising therapeutic target and prognostic biomarker for PCa.

Prevalence and Causes of Discontinuation of Androgen Receptor Inhibitors in Advanced Prostate Cancer Patients and Analysis of Physician Management to Increase Duration of Therapy

OBJECTIVE

To investigate the prevalence and cause of early discontinuation (DC) of androgen receptor inhibitor (ARi) in advanced prostate cancer (PCa) patients. Additionally, to study the effect of changing ARi vs dose reduction on duration of treatment (DOT).

MATERIALS AND METHODS

A retrospective cohort study of 333 patients with advanced PCa who started ARi between 2016 and 2020 was performed. ARi medication, treatment duration, reason for DC, stage of PCa, prostate specific antigen, Gleason score, and prior PCa treatments were collected. The cohort was divided into 2 subgroups, patients that stayed on one medication (Group A) vs patients who changed ARi medication (Group B). Student's t test, chi-square test, and Kaplan-Meier survival analysis were performed.

RESULTS

At 1 year 28.8% of patient's had discontinued ARi. Reasons for DC were side effects (34.4%), death (34.4%), and cancer progression (18.8%). DOT was 13 months for enzalutamide, 13.7 months for abiraterone, 7.6 months for darolutamide, and 12.1 months for apalutamide. Average DOT for patients with a dose change was 13.4 months, similar to those without dose change at 13.9 months (P = .630). DOT was 12.7 months in Group A vs 19.8 months in Group B (P = .001).

CONCLUSION

In our study population DC of ARi is higher than reported in the published trials. Providing patients with an alternative ARi is associated with an increase in DOT while dose reduction is not. It is important for clinicians to understand the causes of early DC to develop strategies to maximize duration of therapy for management of advanced PCa patients.

Inhibition of nicotinamide dinucleotide salvage pathway counters acquired and intrinsic poly(ADP-ribose) polymerase inhibitor resistance in high-grade serous ovarian cancer

Epithelial ovarian cancer is the most lethal gynecological malignancy, owing notably to its high rate of therapy-resistant recurrence in spite of good initial response to chemotherapy. Although poly(ADP-ribose) polymerase inhibitors (PARPi) have shown promise for ovarian cancer treatment, extended therapy usually leads to acquired PARPi resistance. Here we explored a novel therapeutic option to counter this phenomenon, combining PARPi and inhibitors of nicotinamide phosphoribosyltransferase (NAMPT). Cell-based models of acquired PARPi resistance were created through an in vitro selection procedure. Using resistant cells, xenograft tumors were grown in immunodeficient mice, while organoid models were generated from primary patient tumor samples. Intrinsically PARPi-resistant cell lines were also selected for analysis. Our results show that treatment with NAMPT inhibitors effectively sensitized all in vitro models to PARPi. Adding nicotinamide mononucleotide, the resulting NAMPT metabolite, abrogated the therapy-induced cell growth inhibition, demonstrating the specificity of the synergy. Treatment with olaparib (PARPi) and daporinad (NAMPT inhibitor) depleted intracellular NAD+ , induced double-strand DNA breaks, and promoted apoptosis as monitored by caspase-3 cleavage. The two drugs were also synergistic in mouse xenograft models and clinically relevant patient-derived organoids. Therefore, in the context of PARPi resistance, NAMPT inhibition could offer a promising new option for ovarian cancer patients.

Couples coping with advanced prostate cancer: an explorative study on decision-making preferences, self-efficacy and fear of progression

PURPOSE

To date, there is a lack of understanding of the treatment/disease-related health behaviors of patients with advanced prostate cancer (PCa) and their spouses. The purpose of this study was to explore the characteristics of treatment decision-making (DM) preferences, general self-efficacy (SE) and fear of progression (FoP) among couples coping with advanced PCa.

METHODS

In this explorative study, 96 patients with advanced PCa and their spouses answered the multiple choice version of the Control Preferences Scale (CPS, regarding DM), General Self-Efficacy Short Scale (ASKU, regarding SE), and short form of the Fear of Progression Questionnaire (FoP-Q-SF, regarding FoP). Corresponding questionnaires were employed for patients' spouses were evaluated, and correlations were subsequently drawn.

RESULTS

More than half of the patients (61%) and spouses (62%) preferred active DM. Collaborative DM was preferred by 25% of patients and 32% of spouses, and 14% of patients and 5% of spouses preferred passive DM. FoP was significantly higher among spouses than among patients (p < 0.001). The difference in SE was not significant between patients and spouses (p = 0.064). FoP and SE negatively correlated among patients (r = - 0.42; p < 0.001) and among spouses (r = - 0.46; p < 0.001). DM preference did not correlate with SE and FoP.

CONCLUSIONS

High FoP and low general SE are related among both patients with advanced PCa and their spouses. FoP seems to be higher among female spouses than among patients. Couples seem to be largely in agreement when it comes to playing an active role in treatment DM.

TRIAL REGISTRATION

www.germanctr.de , number DRKS 00013045.

HMMR promotes prostate cancer proliferation and metastasis via AURKA/mTORC2/E2F1 positive feedback loop

Although dysregulated HMMR is linked to prostate cancer (PCa) prognosis, the precise mechanisms remain unclear. Here, we sought to elucidate the role of HMMR in PCa progression as well as underlying mechanism. Herein, we found that upregulation of HMMR frequently observed in PCa samples and was associated with poor prognosis. Additionally, HMMR significantly promoted PCa proliferation and metastasis through gain- and loss-of function approaches in vitro and in vivo. Mechanistically, HMMR may interact with AURKA and elevated AURKA protein level through inhibiting ubiquitination-mediated degradation, which subsequently activated mTORC2/AKT pathway to ensure the reinforcement of PCa progression. Moreover, upregulated E2F1 caused from sustained activation of mTORC2/AKT pathway in turn function as transcription factor to promote HMMR transcription, thereby forming a positive feedback loop to trigger PCa progression. Importantly, administration of the mTOR inhibitor partially antagonised HMMR-mediated PCa progression in vivo. In summary, we not only reveal a novel possible post-translation mechanism mediated by HMMR involved in AURKA regulation, but also describe a positive feedback loop that contributes to PCa deterioration, suggesting HMMR may serve as a potential promising therapeutic target in PCa.

Inhibition of castration-resistant prostate cancer growth by genistein through suppression of AKR1C3

Background

Prostate cancer is the second leading cause of cancer-related death among males in America. The patients' survival time is significantly reduced after prostate cancer develops into castration-resistant prostate cancer (CRPC). It has been reported that AKR1C3 is involved in this progression, and that its abnormal expression is directly correlated with the degree of CRPC malignancy. Genistein is one of the active components of soy isoflavones, and many studies have suggested that it has a better inhibitory effect on CRPC.

Objective

This study aimed to investigate the antitumor effect of genistein on CRPC and the potential mechanism of action.

Design

A xenograft tumor mouse model established with 22RV1 cells was divided into the experimental group and the control group, and the former was given 100 mg/kg.bw/day of genistein, with 22RV1, VCaP, and RWPE-1 cells cultured in a hormone-free serum environment and treated with different concentrations of genistein (0, 12.5, 25, 50, and 100 μmol/L) for 48 h. Molecular docking was used to elucidate the molecular interactions between genistein and AKR1C3.

Results

Genistein inhibits CRPC cell proliferation and in vivo tumorigenesis. The western blot analysis confirmed that the genistein significantly inhibited prostate-specific antigen production in a dose-dependent manner. In further results, AKR1C3 expression was decreased in both the xenograft tumor tissues and the CRPC cell lines following genistein gavage feeding compared to the control group, with the reduction becoming more obvious as the concentration of genistein was increased. When the genistein was combined with AKR1C3 small interfering ribonucleic acid and an AKR1C3 inhibitor (ASP-9521), the inhibitory effect on the AKR1C3 was more pronounced. In addition, the molecular docking results suggested that the genistein had a strong affinity with the AKR1C3, and that it could be a promising AKR1C3 inhibitor.

Conclusion

Genistein inhibits the progression of CRPC via the suppression of AKR1C3.

Semiautomated pelvic lymph node treatment response evaluation for patients with advanced prostate cancer: based on MET-RADS-P guidelines

BACKGROUND

The evaluation of treatment response according to METastasis Reporting and Data System for Prostate Cancer (MET-RADS-P) criteria is an important but time-consuming task for patients with advanced prostate cancer (APC). A deep learning-based algorithm has the potential to assist with this assessment.

OBJECTIVE

To develop and evaluate a deep learning-based algorithm for semiautomated treatment response assessment of pelvic lymph nodes.

METHODS

A total of 162 patients who had undergone at least two scans for follow-up assessment after APC metastasis treatment were enrolled. A previously reported deep learning model was used to perform automated segmentation of pelvic lymph nodes. The performance of the deep learning algorithm was evaluated using the Dice similarity coefficient (DSC) and volumetric similarity (VS). The consistency of the short diameter measurement with the radiologist was evaluated using Bland-Altman plotting. Based on the segmentation of lymph nodes, the treatment response was assessed automatically with a rule-based program according to the MET-RADS-P criteria. Kappa statistics were used to assess the accuracy and consistency of the treatment response assessment by the deep learning model and two radiologists [attending radiologist (R1) and fellow radiologist (R2)].

RESULTS

The mean DSC and VS of the pelvic lymph node segmentation were 0.82 ± 0.09 and 0.88 ± 0.12, respectively. Bland-Altman plotting showed that most of the lymph node measurements were within the upper and lower limits of agreement (LOA). The accuracies of automated segmentation-based assessment were 0.92 (95% CI: 0.85-0.96), 0.91 (95% CI: 0.86-0.95) and 75% (95% CI: 0.46-0.92) for target lesions, nontarget lesions and nonpathological lesions, respectively. The consistency of treatment response assessment based on automated segmentation and manual segmentation was excellent for target lesions [K value: 0.92 (0.86-0.98)], good for nontarget lesions [0.82 (0.74-0.90)] and moderate for nonpathological lesions [0.71 (0.50-0.92)].

CONCLUSION

The deep learning-based semiautomated algorithm showed high accuracy for the treatment response assessment of pelvic lymph nodes and demonstrated comparable performance with radiologists.