Hormone-naive Prostate Cancer Research Articles

PRL-mediated STAT5B/ARRB2 pathway promotes the progression of prostate cancer through the activation of MAPK signaling

Previous study showed that higher expression of prolactin (PRL) was found in CRPC samples compared with hormone-naive prostate cancer (HNPC) and benign prostatic hyperplasia (BPH) samples. We further investigate the function of PRL in prostate cancer (PCa) and explored its downstream effects. We found heterogeneous expression of the PRLR in clinical prostate samples. The VCaP and 22Rv1 cells exhibited PRLR expression. Among the downstream proteins, STAT5B was the dominant subtype in clinical samples and cell lines. Human recombinant PRL stimulation of PCa cells with PRLR expression resulted in increased phosphorylation of STAT5B(pSTAT5B) and progression of PCa in vitro and in vivo, and STAT5B knockdown can suppress the malignant behavior of PCa. To understand the mechanism further, we performed Bioinformatic analysis, ChIP qPCR, and luciferase reporter gene assay. The results revealed that ARRB2 was the transcription target gene of STAT5B, and higher expression of ARRB2 was related to higher aggression and poorer prognosis of PCa. Additionally, Gene set enrichment analysis indicated that higher expression of ARRB2 was significantly enriched in the MAPK signaling pathway. Immunohistochemistry (IHC) demonstrated elevated pSTAT5B, ARRB2, and pERK1/2 expression levels in CRPC tissues compared to HNPC and BPH. Mechanically, ARRB2 enhanced the activation of the MAPK pathway by binding to ERK1/2, thereby promoting the phosphorylation of ERK1/2 (pERK1/2). In conclusion, our study demonstrated that PRL stimulation can promote the progression of PCa through STAT5B/ARRB2 pathway and activation of MAPK signaling, which can be suppressed by intervention targeting STAT5B. Blockade of the STAT5B can be a potential therapeutic target for PCa.

Real-world experience on tolerability and safety of relugolix combined with androgen signaling inhibitors in patients with advanced prostate cancer.

85 Background: Relugolix is the first oral GNRH antagonist approved by the FDA in 2021 for the treatment of advanced prostate cancer (PCa). Approval was based on HERO study, which showed a rapid and sustained testosterone suppression superior to that of Leuprolide coupled with a significantly shorter time to eugonad state after discontinuation. Relugolix was associated with a 54% lower risk of major adverse cardiovascular events as compared with Leuprolide. There is very little data available regarding the tolerability safety of Relugolix in combination Enhanced Androgen Signaling Inhibitors (ASI). Here we provide real world experience on the combination of Relugolix and ASIs in patients(pts) with advanced PCa, focusing on safety, tolerability and pharmacodynamic outcome measures. Methods: Houston Methodist Genitourinary Oncology records were reviewed for identification of pts treated with combination Relugolix plus ASI for at least 1 month, from 09/21 to 07/23. Data collected included pts’ baseline and tumor characteristics, cardiovascular and metabolic comorbidities concomitant medication. We recorded Adverse Events, potential Drug Drug Interaction (DDI) and Testosterone (T) and PSA decline. Results: We report 152 advanced hormone-naive PCa pts with median age of 71 (range 48-96). 81% were White or/and Hispanic, 17 % black, 2 % Asian. Majority (90%) had at least 1 cardiovascular risk factor; hypertension (72%), hyperlipidemia (52%), obesity (41 %), diabetes mellitus (26%), coronary artery disease (30%) and atrial fibrillation (13%). ASIs combined with Relugolix included: Darolutamide (78%), Abiraterone (14%), Apalutamide (7%) and Enzalutamide (1%). All but one pt were compliant (99%). Median treatment exposure is 8 months (range 1 -21). All pts had baseline Testosterone >150ng/dL. All pts reached castrate T levels and 90% of patients achieved a T < 20 ng/dL. 55% pts reached PSA <0.1 at median of 4ms, 75% PSA decline > 90% and 91% PSA decline ≥50%. 7% pts discontinued Relugolix due to adverse events. Three pts (2%) had a major adverse cardiovascular event, including one sudden death, one with congestive heart failure, and one with myocardial infarction. Two pts (1%) reported grade 3 fatigue. G3 LFT elevations recorded in 2 pts (1%). No clinical signals of DDI reported. Conclusions: This is the first large original report of the combination of Relugolix with ASIs in real world practice. The combination has a favorable safety and tolerability profile with no new safety concerns. No new DDI concerns were raised. These findings in combination with pharmacodynamic outcome measures of T / PSA support the use of Relugolix in combination with ASIs as standard of care in advanced PCa.

Cell-Free DNA Genomic Profiling and Its Clinical Implementation in Advanced Prostate Cancer.

Most men with prostate cancer (PCa), despite potentially curable localized disease at initial diagnosis, progress to metastatic disease. Despite numerous treatment options, choosing the optimal treatment for individual patients remains challenging. Biomarkers guiding treatment sequences in an advanced setting are lacking. To estimate the diagnostic potential of liquid biopsies in guiding personalized treatment of PCa, we evaluated the utility of a custom-targeted next-generation sequencing (NGS) panel based on the AmpliSeq HD Technology. Ultra-deep sequencing on plasma circulating free DNA (cfDNA) samples of 40 metastatic castration-resistant PCa (mCRPC) and 28 metastatic hormone-naive PCa (mCSPC) was performed. CfDNA somatic mutations were detected in 48/68 (71%) patients. Of those 68 patients, 42 had matched tumor and cfDNA samples. In 21/42 (50%) patients, mutations from the primary tumor tissue were detected in the plasma cfDNA. In 7/42 (17%) patients, mutations found in the primary tumor were not detected in the cfDNA. Mutations from primary tumors were detected in all tested mCRPC patients (17/17), but only in 4/11 with mCSPC. AR amplifications were detected in 12/39 (31%) mCRPC patients. These results indicate that our targeted NGS approach has high sensitivity and specificity for detecting clinically relevant mutations in PCa.

Prognostic impact of serum testosterone in metastatic hormone-naive prostate cancer: a systematic review and meta-analysis.

In daily practice, there is an unmet medical need for biomarkers that facilitate therapeutic decision-making in the metastatic hormone sensitive prostate cancer (mHSPC) scenario. Although recent studies have highlighted the potential of testosterone as a prognostic and predictive marker in prostate cancer, the evidence is controversial. The objective of this review was to summarize and analyze the scientific evidence regarding the prognostic role of basal testosterone levels in patients with mHSPC. A systematic review was performed. Three authors selected the articles from Web of Science, PubMed, Scopus, and Cochrane Library electronic databases. Risk of bias was assessed by the Newcastle Ottawa Scale. Most of the selected articles suggest that low testosterone levels before starting hormonal blockade imply a worse prognosis for patients with mHSPC. However, the quality of the evidence is poor, the studies are heterogeneous, and it is not possible to meta-analyze most of the published results. Testosterone is an accessible and affordable biomarker. If it were correctly demonstrated that it harbors a prognostic and/or predictive role in the mHSPC setting, it could represent an advance in decision-making in these patients. Well designed prospective studies are needed to correctly answer this question.

A phase 2, randomized, open-label study comparing the effects of darolutamide versus enzalutamide monotherapy on serum testosterone levels in patients with hormone-naive prostate cancer: ARAMON study.

TPS5111 Background: Darolutamide is a structurally distinct and highly potent androgen receptor inhibitor with low blood–brain barrier penetration. In the phase 3 ARAMIS study (NCT02200614) of patients with nonmetastatic castration-resistant prostate cancer, treatment with darolutamide significantly improved metastasis-free survival and overall survival versus placebo, with a favorable safety profile. The incidences of central nervous system adverse events (AEs; e.g. falls, memory impairment, and depression) showed a ≤2% difference between the darolutamide and placebo groups. Fatigue was the only AE with an incidence of > 10% for darolutamide (13.2% vs 8.3% for placebo). In a separate neuroimaging study of healthy volunteers, cerebral blood flow was not altered in patients treated with darolutamide but was significantly reduced in brain areas related to cognition in patients treated with enzalutamide. Furthermore, it is postulated that the low blood–brain barrier penetration of darolutamide may result in lower serum testosterone elevations than those seen with enzalutamide, with the potential of leading to fewer associated feminizing AEs. The objective of ARAMON (NCT05526248) is to compare the effect of darolutamide and enzalutamide monotherapy on post-treatment testosterone levels in patients with hormone-naive prostate cancer experiencing biochemical recurrence after definitive treatment for localized disease. Methods: ARAMON is a two-stage, open-label, phase 2 study of patients with histologically or cytologically confirmed adenocarcinoma of the prostate who have biochemical recurrence after radical primary prostatectomy or radiation therapy, with a prostate-specific antigen (PSA) doubling time of ≤20 months, baseline serum testosterone > 150 ng/dL, and Eastern Cooperative Oncology Group performance status 0/1. During a 52-week lead-in phase, 25 patients will receive darolutamide 600 mg twice daily. If criteria based on serum testosterone increase from baseline to Week 12 are met, the study will proceed to a 52-week randomized phase in which the effects of darolutamide (600 mg twice daily, n = 20) will be compared with the effects of enzalutamide (160 mg once daily, n = 20). The primary endpoint of both phases is the change in serum testosterone level from baseline to Week 12. Secondary endpoints of the randomized phase include the change in serum testosterone levels from baseline to Weeks 24 and 52; PSA at Weeks 4, 12, 24, 36, and 52; changes in blood levels of markers for glucose, lipid metabolism, and endocrine function related to sex hormones; safety; and quality of life. Safety will be assessed through AE monitoring. The first of the 25 planned patients in the lead-in phase was enrolled on January 13, 2023. Clinical trial information: NCT05526248 .

A comparison of the sarcopenic effect of androgen receptor-axis-targeted agents vs. androgen deprivation alone in patients with metastatic prostate cancer.

Androgen deprivation therapy (ADT) with androgen receptor axis-targeted (ARAT) therapy is the standard of care provided to patients with metastatic prostate cancer. While effective, it results in sequelae, such as loss of skeletal muscle mass. In this study, we compared the sarcopenic effects of abiraterone and enzalutamide, two ARATs used to treat metastatic prostate cancer. Our cohort was comprised of 55 patients diagnosed with metastatic hormonenaive prostate cancer from 2014-2019. Patients were divided into three treatment groups: gonadotropin-releasing hormone (GnRH ) agonist alone; GnRH agonist combined with abiraterone acetate; and GnRH agonist combined with enzalutamide. We then compared axial computed tomographic (CT) scans at the L3 level before and after the initiation of hormone therapy for each patient. A skeletal muscle index (SMI) was calculated for each patient, and alongside clinical data, was compared between the three groups. One-way analysis of variance (ANOVA) and Fisher's exact test were used to compare means and proportions, respectively. Baseline clinical characteristics were not significantly different between the three groups. The percent SMI change and number of newly sarcopenic patients were not found to be significantly different between the groups. The only variable that was significantly different across the three groups was time between CT scans. Although we found no significant difference in the sarcopenic effects of GnRH alone, GnRH with abiraterone, or GnRH with enzalutamide in our cohort of 55 hormone-naive metastatic prostate cancer patients, overall decreases in muscle mass were observed for all three groups. This highlights the importance of muscle-retaining strategies for patients undergoing ADT for metastatic prostate cancer, regardless of therapeutic regimen.

A phase 2 randomized open-label study of oral darolutamide monotherapy vs. androgen deprivation therapy in men with hormone-naive prostate cancer (EORTC-GUCG 1532).

160 Background: Darolutamide is androgen-receptor (AR) inhibitor with low blood–brain barrier penetration and limited potential for clinically relevant drug–drug interactions. Darolutamide has been shown to increase overall survival in combination with androgen deprivation therapy (ADT) in patients with newly diagnosed metastatic hormone sensitive prostate cancer (PC) and, in combination with docetaxel, in men with non-metastatic castration resistant PC. This phase 2 study assessed the efficacy and safety of DARO as a monotherapy without ADT in patients with non-castrate testosterone (T) levels (≥230 ng/dL). Methods: This was a 24-wk, open-label, randomized study of patients with hormone-naïve, histologically confirmed prostate cancer (all stages, with a max of 4 metastatic lesions) requiring hormonal treatment, an ECOG PS score of 0, and a life expectancy >1 y. All patients received DARO 600 mg bid or commercially available LHRH analogue. The primary endpoint is PSA response defined as a ≥ 80% decline at week 24 relative to baseline, in the DARO study arm. The ADT arm is used as an internal control. Secondary endpoints included changes in T levels, safety/tolerability, and quality of life. Results: Among 61 men enrolled, the median (range) age was 72 y (53-86y); 49.2% had metastases; 14.8% and 62.3% had undergone prostatectomy or radiotherapy before study entry. The median (range) of PSA at baseline was 8.9 ng/mL (2.2-333.8). In the DARO arm, the evaluable population with available PSA values at baseline and week 24 consisted of 21 patients. The PSA response rate (>80% PSA decline at wk 24) was 100%, with a median (range) decrease of -99.6% (-94.3, -100) at wk 24 in the DARO arm. Serum T levels increased by a median (range) of 43.4% (5.7-144.0) at wk 24, compared with baseline. In the DARO arm, 45.2% of men reported drug-related AEs (mostly Grade 1 or 2). Most frequent treatment-emergent AEs included gynaecomastia (19.4%), fatigue (12.9%), and hot flush (12.9%). 3.1% of men experienced SAEs, none of which were drug related. HR-QoL measures and ADT arm results will be presented as internal reference. Conclusions: DARO monotherapy (600 mg bid) was associated with significant PSA response in nearly all men with hormone-naïve prostate cancer. Testosterone level changes and most common AEs (gynecomastica, fatigue and hot flush) were consistent with potent AR inhibition. Clinical trial information: NCT02972060 .

Retrospective validation of bone risk stratification criteria for men with de novo metastatic hormone-naive prostate cancer in China.

Bone metastasis has been suggested to be a significant impactor on the prognosis of newly diagnosed de novo metastatic hormone-sensitive prostate cancer (mHSPC), and some risk stratification models have been proposed on the basis of this hypothesis. However, the effectiveness of these risk stratification criteria has not been fully evaluated in China. This study aimed to evaluate the effectiveness of the risk stratification models in China. A total of 140 patients who were newly diagnosed with metastatic prostate cancer followed by primary androgen deprivation-based therapy from January 2008 to June 2021 at our institution were enrolled in this study. The patients were divided into different groups on the basis of high- and low-volume disease (H/LVD) criteria, high-and low-risk disease (H/LRD) criteria, extremity bone metastasis criteria (EBM), and extent of disease (EOD) criteria. The area under the receiver operating characteristic (ROC) curve (AUC) and decision curve analysis (DCA) were used to compare the validity and net benefit of these models. Using the Cox proportional hazards model, we performed univariable and multivariable analyses of the factors influencing overall survival (OS) and the time of progression to metastatic castration-resistant prostate cancer (CRPC). The median patient age was 72 years. Most patients had a Gleason score ≥8 (102 cases, 72.9%) and clinical T stage >2 (75 cases, 53.6%). The median follow-up time was 25 months (range, 2-95 months). Ninety-two patients progressed to CRPC and fifty-seven patients died during the follow-up. The AUC of OS and CRPC showed that the EOD model had higher validity than the other risk stratification models. DCA shows that the net benefit of the EOD model on OS was better than that of the other risk stratification models. As for CRPC, the net benefit of the EOD model was second only to that of the H/LRD model when the threshold was <0.5; however, when the threshold was >0.5, the EOD model outperformed the other models. The effectiveness of EOD as an independent prognostic variable was verified through univariable and multivariable analyses. The EOD model yields reasonable risk stratification for use in Chinese mHSPC patients, providing further evidence supporting its role in clinical decision-making.

The Neuropilin-1/PKC axis promotes neuroendocrine differentiation and drug resistance of prostate cancer

BackgroundNeuroendocrine prostate cancer (NEPC) is a multi-resistant variant of prostate cancer (PCa) that has become a major challenge in clinics. Understanding the neuroendocrine differentiation (NED) process at the molecular level is therefore critical to define therapeutic strategies that can prevent multi-drug resistance.MethodsUsing RNA expression profiling and immunohistochemistry, we have identified and characterised a gene expression signature associated with the emergence of NED in a large PCa cohort, including 169 hormone-naïve PCa (HNPC) and 48 castration-resistance PCa (CRPC) patients. In vitro and preclinical in vivo NED models were used to explore the cellular mechanism and to characterise the effects of castration on PCa progression.ResultsWe show for the first time that Neuropilin-1 (NRP1) is a key component of NED in PCa cells. NRP1 is upregulated in response to androgen deprivation therapies (ADT) and elicits cell survival through induction of the PKC pathway. Downmodulation of either NRP1 protein expression or PKC activation suppresses NED, prevents tumour evolution toward castration resistance and increases the efficacy of docetaxel-based chemotherapy in preclinical models in vivo.ConclusionsThis study reveals the NRP1/PKC axis as a promising therapeutic target for the prevention of neuroendocrine castration-resistant variants of PCa and indicates NRP1 as an early transitional biomarker.

Prospects of Treating Prostate Cancer through Apalutamide: A Mini-Review.

Prostate cancer is considered the second most diagnosed cancer, and one of the most common causes of death from cancer in men. Apalutamide is an effective, safe, and well-tolerated agent used for the treatment of men with non-metastatic Castration-Resistant Prostate Cancer (nmCRPC) and metastatic Hormone-Naive Prostate Cancer (mHNPC). Androgen receptor signaling is a leading factor that drives these prostate tumors. USFDA has approved apalutamide on 14 February 2018 as an agent that targets androgen receptor signaling through inhibition causing significant improvement in metastasis-free survival in patients with prostate cancer. In this review, various aspects related to apalutamide have been summarized which involve the mechanism of action, chemistry, synthesis, pharmacokinetics, pharmacodynamics, adverse reactions, and safety parameters. The literature was thoroughly searched in the relevant databases to identify studies published in this field during recent years. Special attention has been given to apalutamide clinical trials phases and its promising future as one of the first-line agents for the treatment of patients with advanced prostate cancer. Ongoing trials are progressing for apalutamide monotherapy and also for its combinations in other disease settings. The expected results of such trials will shape the future scenario of prostate cancer therapy. This review article has highlighted different aspects of Apalutamide like its mechanism of action, adverse effects, pharmacokinetics, pharmacodynamics, clinical trials among others. The contents of this article should make an excellent read for prospective researchers in this field.

Impact of Progressive Site-Directed Therapy in Oligometastatic Castration-Resistant Prostate Cancer on Subsequent Treatment Response.

Simple SummaryLocal treatment for oligometastatic hormone-naive prostate cancer has been shown to be effective in phase II trials. As for the efficacy of targeted therapy for oligometastatic castration-resistant prostate cancer, the results of the phase trial are not yet available, but the number of reports showing efficacy by retrospective analysis is increasing. Progressive site-directed therapy has been shown to delay the next intervention and prolong progression-free survival, but its impact on subsequent treatment efficacy and contribution to overall survival has not been reported. The purpose of this retrospective study is to evaluate the impact of progressive site-directed therapy for oligometastatic castration-resistant prostate cancer on the subsequent treatment outcomes. We found that progressive site-directed therapy was associated with better response to subsequent androgen receptor axis-targeted drugs and better overall survival. Progressive site-directed therapy for oligometastatic castration-resistant prostate cancer may improve subsequent oncological outcomes.The purpose of this study was to evaluate the impact of progressive site-directed therapy (PSDT) for oligometastatic castration-resistant prostate cancer (OM-CRPC) on the efficacy of subsequent androgen receptor axis-targeted (ARAT) drugs, and to demonstrate the possibility of prolonging overall survival (OS). We performed a retrospective analysis of 15 OM-CRPC patients who underwent PSDT and subsequently received first-line ARAT drugs (PSDT group) and 13 OM-CRPC patients who were treated with first-line ARAT drugs without PSDT (non-PSDT group). PSDT was performed with the intention of treating all progressing sites detected by whole-body diffusion-weighted MRI with radiotherapy. Thirteen patients (86.7%) treated with PSDT had a decrease in PSA levels, which was at least 50% in 10 (66.7%) patients. The median PSA progression-free survival (PFS) for PSDT was 7.4 months. The median PSA-PFS for ARAT was 27.2 months in patients in the PSDT group and 11.7 months in the non-PSDT group, with a significant difference between the two groups (hazard ratio [HR], 0.28; p = 0.010). The median OS was not reached in the PSDT group and was significantly longer than 44.5 months in the non-PSDT group (HR, 0.11; p = 0.014). In OM-CRPC, PSDT may improve the efficacy of subsequent ARAT and OS.

Prevalence of skeletal-related events in hormone-naive prostate cancer in a low resource setting

Presentation with symptoms of advanced prostate cancer is prevalent in developing societies. The objective of this study was to determine the rate of and factors associated with skeletal-related events (SREs) at presentation with hormone-naïve prostate cancer. Records of 331 consecutive prostate cancer patients from January 2009 to April 2018 were reviewed. The prevalence of SRE at the presentation was determined. In addition, the relationships between SRE and age of patient, duration of clinical features, serum total prostate-specific antigen (tPSA) and biopsy Gleason score (GS) at presentation were evaluated. Analyses were done with IBM SPSS® version 25. Mean age was 69.8 ± 8.0 years. While 43.8% of patients had lower urinary tract symptoms (LUTS) only, 51.4% had LUTS and other features of disease progression. Only 2.1% of the cases were confirmed from screen detection of elevated serum tPSA. SREs were observed in 11.8% at first presentations with hormone-naïve prostate cancer. Symptom duration (odds ratio [OR] 0.94; 95% confidence interval [CI] 0.90-0.99; P = 0.02), anaemia that could not be attributed to gross haematuria or external blood loss (OR 9.6; 95% CI 3.12-29.52; P < 0.001) and transrectal biopsy GS (OR 1.61; 95% CI 1.17-2.22; P = 0.003 ) were significantly associated with SREs at presentation with hormone-naïve prostate cancer. Evidence exists that patients who present with SREs from more aggressive prostate cancers may have had more rapid symptom progression, but not a longer delay before presentation.

A transcriptional biosensor to monitor single cancer cell therapeutic responses by bioluminescence microscopy.

When several life-prolonging drugs are indicated for cancer treatment, predictive drug-response tumor biomarkers are essential to guide management. Most conventional biomarkers are based on bulk tissue analysis, which cannot address the complexity of single-cell heterogeneity responsible for drug resistance. Therefore, there is a need to develop alternative drug response predictive biomarker approaches that could directly interrogate single-cell and whole population cancer cell drug sensitivity. In this study, we report a novel method exploiting bioluminescence microscopy to detect single prostate cancer (PCa) cell response to androgen receptor (AR)-axis-targeted therapies (ARAT) and predict cell population sensitivity.Methods: We have generated a new adenovirus-delivered biosensor, PCA3-Cre-PSEBC-ITSTA, which combines an integrated two-step transcriptional amplification system (ITSTA) and the activities of the prostate cancer antigen 3 (PCA3) and modified prostate-specific antigen (PSEBC) gene promoters as a single output driving the firefly luciferase reporter gene. This system was tested on PCa cell lines and on primary PCa cells. Single cells, exposed or not to ARAT, were dynamically imaged by bioluminescence microscopy. A linear discriminant analysis (LDA)-based method was used to determine cell population sensitivities to ARAT.Results: We show that the PCA3-Cre-PSEBC-ITSTA biosensor is PCa-specific and can dynamically monitor single-cell AR transcriptional activity before and after ARAT by bioluminescence microscopy. After biosensor transduction and bioluminescence microscopy single-cell luminescence dynamic quantification, LDA analysis could discriminate the cell populations overall ARAT sensitivity despite heterogeneous single-cell responses. Indeed, the biosensor could detect a significant decrease in AR activity following exposure to conventional ARAT in hormone-naive primary PCa cells, while in castration-resistant PCa patients, treatment response correlated with the observed clinical ARAT resistance.Conclusion: The exploitation of bioluminescence microscopy and multi-promoter transcriptionally-regulated biosensors can aptly define the overall treatment response of patients by monitoring live single cell drug response from primary cancer tissue. This approach can be used to develop predictive biomarkers for drug response in order to help clinicians select the best drug combinations or sequences for each patient.

The treatment landscape of metastatic prostate cancer.

The treatment landscape of metastatic prostate cancer has evolved significantly over the past two decades. Several landmark phase 3 trials led to new drug approvals and rapid changes in therapy options for patients, including drugs with distinct mechanisms of action (e.g., hormonal, chemotherapy, radionuclide, immunotherapy, and targeted therapies). Therapies initially developed in later stages of the disease (metastatic castration resistant prostate cancer) have started to move earlier in the prostate cancer continuum, with new standards of care for metastatic hormone naive prostate cancer and non-metastatic castration resistant prostate cancer. Overall, patients are living longer with a better quality of life. However, despite these significant advances, prostate cancer remains a leading cause of cancer death globally. Disease heterogeneity and the emergence of therapy resistance remain significant barriers, and the identification and application of molecular biomarkers to guide the choice and sequencing of systemic agents are still in early stages. Here we discuss the current treatment landscape of metastatic prostate cancer, clinical challenges, and the emerging role of molecular biomarkers for targeting biologic subsets of advanced disease and co-targeting heterogenous resistance patterns.

Bone Health in Patients With Prostate Cancer: An Evidence-Based Algorithm.

The veteran population has an increasingly high number of patients who have either survived, are currently living with, or are being treated for prostate cancer. Survivorship concerns related to the treatment of this disease is a relevant topic in the Veterans Health Administration, given the longevity of life with localized disease treatment and the fairly durable therapies for metastatic disease. Long-term androgen deprivation therapy (ADT) forms the backbone of treatment for advanced and metastatic castration-sensitive prostate cancer. The potential bone-health complications resulting from treatment with ADT should be recognized as many patients live for prolonged periods with stable or controlled disease. It is well established that prolonged ADT can lead to significant bone loss and increased fracture risk, which increases all-cause mortality and disability. Bone-remodeling agents, such as bisphosphonates and receptor-activated nuclear factor κ-B ligand inhibitors, are recommended to reduce the risk of fragility fractures in patients at high risk due to diminished bone density while on hormone deprivation therapy for hormone-naive prostate cancer. These agents are also indicated at a higher dose to prevent complications from bone metastases in castration-resistant prostate cancer with bone metastases. This article reviews recent studies on bone health in men with prostate cancer and presents an evidence-based algorithm for bone-health monitoring during treatment and recommended interventions.

The lncRNA PTTG3P promotes the progression of CRPC via upregulating PTTG1

Overexpression of certain long non-coding RNAs (lncRNAs) promotes the progression of castration-resistant prostate cancer (CRPC). The significance and potential role of the lncRNA designated pituitary tumour-transforming 3, pseudogene (PTTG3P) in CRPC is unknown. We detected PTTG3P expression by qPCR. Upregulated PTTG3P expression was performed to explore the role of PTTG3P in PCa cells resistant to ADT (androgen deprivation therapy). The relationship among PTTG3P, mir-146a-3p and PTTG1 were validated by qPCR, western blot and luciferase assay. PTTG3P levels were significantly increased in the androgen-independent PC cell lines, as well as in CRPC tissues compared with those of the androgen-dependent prostate cancer cell line LNCaP and tumour tissues of patients with hormone-naive prostate cancers. Enforced expression of PTTG3P in androgen-deprived LNCaP cells significantly enhanced survival, clonogenicity, and tumorigenicity. Further, PTTG3P acted as a competing endogenous RNA (ceRNA, natural miRNA sponge) to upregulate PTTG1 expression by competing for mir-146a-3p in the progression to CRPC. Our findings suggest that PTTG3P promotes the resistance of prostate cancer cells to androgen-deprivation therapy via upregulating PTTG1. PTTG3P may therefore represent a potential target for therapy of CRPC.

TP53 alterations of hormone-na\xefve prostate cancer in the Chinese population

BackgroundProstate cancer (PCa) shows racial disparity in clinical and genomic characteristics, and Asian patients with PCa often present with more aggressive phenotypes at diagnosis. The ability of TP53 to serve as a prognostic biomarker of PCa has been well studied in Western populations. However, no studies to date have examined the role of TP53 in the disparities of primary hormone-naïve prostate cancer (HNPC) between Chinese and Western populations.MethodsWe collected prostate tumors and matched normal tissues or blood samples to perform targeted next-generation sequencing of 94 Chinese primary localized HNPC samples, and correlated these genomic profiles with clinical outcomes. The OncoKB knowledge database was used to identify and classify actionable alterations.ResultsThe aberrations of PTEN, CDK12, and SPOP in Chinese HNPC samples were similar to those in the Western samples. However, we demonstrated an association of a high frequency of TP53 alterations (21/94) with a relatively higher percentage of alterations in the Wnt signaling pathway (15/94) in Chinese HNPC. Additionally, we highlighted alterations of LRP1B as accounting for a high proportion of PCa and found more frequent alterations in CDH1 in Chinese PCa. Of these, only CDH1 alteration was associated with rapid biochemical recurrence (BCR). However, we verified that TP53 status was at the core of the genomic alteration landscape in Chinese HNPC with putative driver mutations because of the strong connections with other signaling pathways. The mutually exclusive relationship between alterations in TP53 and Wnt/CTNNB1 further molecularly characterizes subsets of prostate cancers. Moreover, the alteration of KMT2C was more likely to co-occur with TP53 alteration, indicating a more aggressive phenotype of PCa, which was associated with sensitivity to treatment with poly ADT–ribose polymerase (PARP) inhibitors.ConclusionsDetection of TP53 alterations has clinical utility for guiding precision cancer therapy for HNPC, especially in the Chinese population.

Prognostic significance of p16 expression in high-grade prostate adenocarcinoma.

Management of advanced hormone-naïve prostate cancer (HNPC) is a critical public health issue. Useful prognostic markers are thus needed to select patients who will benefit from recently introduced upfront therapies. p16 expression is an adverse prognostic marker in prostate cancer. The present study aimed to determine whether p16 expression would serve as an adverse prognostic marker in advanced HNPC. A total of 79 patients diagnosed by needle biopsy with adenocarcinoma Gleason score ≥8 between 2010 and 2013 at Aichi Medical University were included in this study. The median patient age was 73 (range 52-87) years. The median follow-up was 62 months (range 2-98). Fourteen patients had p16-positive samples. Fifteen patients died from prostate cancer, 10 of whom were in the p16-positive group. p16 positivity was associated with clinical T stage (P < 0.001), presence of IDC-P (P < 0.001), distant metastasis (P < 0.001) and lymph node metastasis (P < 0.001). These results indicate that p16 expression is associated with adverse prognostic factor of prostate cancer and suggest that p16 expression may provide useful information for treatment planning and identifying suitable candidates for upfront chemotherapy or androgen receptor axis-targeted therapy.

Use of bisphosphonates and other bone supportive agents in the management of prostate cancer-A UK perspective.

To explore the practice and views of uro-oncologists in the UK regarding their use of bone supportive agents in patients with prostate cancer. An expert-devised online questionnaire was completed by members of the British Uro-oncology Group (BUG). Of 160 uro-oncologists invited, 81 completed the questionnaire. Approximately 70% of respondents never use a bone supportive agent in patients with metastatic hormone-naïve prostate cancer on androgen deprivation therapy (ADT). However, use was more frequent in men with metastatic castration-resistant prostate cancer, from first-line treatment onwards. The majority of uro-oncologists do not use a bone supportive agent to prevent skeletal-related events in men with non-metastatic disease unless the individual patient is at an increased risk of osteoporosis. In men with more advanced disease, respondents would use an oral or intravenous (IV) bisphosphonate in 41% and 61% of patients, respectively. Zoledronic acid is the first-choice bone supportive treatment in 77% of cases, with the lack of clinical data cited as a barrier to use for other IV bisphosphonates. Local guidelines also have a significant influence on the use of bone supportive agents, especially with respect to denosumab. Bone mineral density measurement is conducted in approximately 40% of men with ADT exposure of 2 years or longer, or those with metastatic prostate cancer. Uro-oncologists in the UK generally do not use bone supportive agents for men with metastatic hormone-naïve prostate cancer or those with non-metastatic disease. However, increasing the duration of ADT and the presence of castration-resistant metastatic prostate cancer increases use.

Determining the prognostic significance of IKKα in prostate cancer.

As the survival of castration-resistant prostate cancer (CRPC) remains poor, and the nuclear factor-κB (NF-κB) pathways playkey roles in prostate cancer (PC) progression, several studies have focused on inhibiting the NF-κB pathway through generating inhibitory κB kinase subunitα (IKKα) small molecule inhibitors. However, the identification of prognostic markers able to discriminate which patients could benefit from IKKα inhibitors is urgently required. The present study investigated the prognostic value of IKKα, IKKα phosphorylated at serine 180 (p-IKKα S180) and threonine 23 (p-IKKα T23), and their relationship with the androgen receptor (AR) and Ki67 proliferation index to predict patient outcome. A cohort of 115 patients with hormone-naïve PC (HNPC) and CRPC specimens available were used to assess tumor cell expression of proteins within both the cytoplasm and the nucleus by immunohistochemistry. The expression levels were dichotomized (low vs high) to determine the associations between IKKα, AR, Ki67, and patients'Isurvival. In addition, an analysis was performed to assess potential IKKα associations with clinicopathological and inflammatory features, and potential IKKα correlations with other cancer pathways essential for CRPC growth. High levels of cytoplasmic IKKα were associated with a higher cancer-specific survival in HNPC patients with low AR expression (hazards ratio [HR], 0.33; 95% confidence interval [CI] log-rank, 0.11-0.98; P = .04). Furthermore, nuclear IKKα (HR, 2.60; 95% CI, 1.27-5.33; P = .01) and cytoplasmic p-IKKα S180 (HR, 2.10; 95% CI, 1.17-3.76; P = .01) were associated with a lower time to death from recurrence in patients with CRPC. In addition, high IKKα expression was associated with high levels of T-cells (CD3+ P = .01 and CD8+ P = .03) in HNPC; however, under castration conditions, high IKKα expression was associated with high levels of CD68+ macrophages (P = .04), higher Gleason score (P = .01) and more prostate-specific antigen concentration (P = .03). Finally, we identified crosstalk between IKKα and members of the canonical NF-κB pathway in the nucleus of HNPC. Otherwise, IKKα phosphorylated by noncanonical NF-κB and Akt pathways correlated with members of the canonical NF-κB pathway in CRPC. The present study reports that patients with CRPC expressing high levels of nuclear IKKα or cytoplasmic p-IKKα S180, which associated with a lower time to death from recurrence, may benefit from IKKα inhibitors.