Initial hormonal management of androgen-sensitive metastatic, recurrent, or progressive prostate cancer: 2006 update of an American Society of Clinical Oncology practice guideline

Assessing the effects of prostate cancer therapies on cardiovascular health

Contemporary advances in prostate cancer treatments have markedly improved patient outcomes, yet concerns persist regarding the increased cardiovascular toxicity of prostate cancer treatments, which is multifaceted. Local therapies entail non-negligible cardiovascular risks. The effects of androgen deprivation therapy, which is pivotal in disease management, on cardiovascular health remains contentious, with gonadotropin-releasing hormone agonists and antagonists showing varying cardiovascular outcomes. Despite the ongoing controversy over the cardiovascular risks of gonadotropin-releasing hormone antagonists versus agonists, current evidence does not support favouring one over the other based solely on cardiovascular risk. Combination therapy with androgen receptor pathway inhibitors and androgen deprivation therapy shows additive cardiovascular risks, but robust comparative data are lacking. Chemotherapies such as docetaxel and cabazitaxel, along with emerging targeted therapies and radiopharmaceuticals, are associated with varied cardiovascular risks, necessitating personalized patient assessment. Clinicians should adhere to cardio-oncology guidelines when prescribing therapeutic agents, especially for patients with pre-existing cardiovascular conditions. Optimal monitoring and management strategies are essential to mitigate cardiovascular morbidity and mortality.

Advances in ferroptosis for castration-resistant prostate cancer treatment: novel drug targets and combination therapy strategies

BACKGROUND

Metastatic prostate cancer (PCa) has much lower survival and ultimately develops castration resistance, which expects novel targets and therapeutic approaches. As a result of iron-dependent lipid peroxidation, ferroptosis triggers programmed cell death and has been associated with castration-resistant prostate cancer (CRPC).

SUBJECTS

To better understand how ferroptosis can be used to treat CRPC, we reviewed the following: First, ferroptosis mechanisms and characteristics. We then pay attention to ferroptosis effects on CRPC, and the relationship between ferroptosis and CRPC treatment. Finally, we'd like to figure out if ferroptosis could predict the prognosis of CRPC thus screening early for populations that may benefit from appropriate therapies.

RESULTS

The review demonstrated that ferroptosis regulators like PI3K/AKT/mTOR, DECR1 et al., have a significant role in the development of CRPC and that several inducers of ferroptosis, such as erastin, BSO, RSL3, and FIN56, have already demonstrated their effects in that area. What's more, ferroptosis is crucial for radiation-induced anticancer effects by inducing lipid peroxidation and regulating p53, AMPK, and others. Additionally, it has been discovered that certain GPX4 and SLC7A11 inhibitors can increase radiosensitivity, which brings new combination strategies. Finally, among the genes associated with ferroptosis, which may be excellent predictors of prostate cancer prognosis, several risk models have been developed and shown promising predictive capabilities.

CONCLUSIONS

Ferroptosis can serve as a potential therapeutic target for CRPC, and could be a new strategy for combination therapy. Moreover, ferroptosis-related genes may be great indicators of PCa prognosis. Further research on ferroptosis in CRPC therapy can benefit from the frameworks provided by this review.

The effect of SP/NK1R on expression and activity of glutaredoxin and thioredoxin proteins in prostate cancer cells

Substance P (SP), an important neuropeptide, has a crucial role in the progression of several cancers, including prostate cancer, through interacting with the neurokinin-1 receptor (NK1R). Oxidative stress is also involved in the onset and progression of prostate cancer. However, no studies have been performed on the cross-talk between the SP/NK1R system and cellular redox balance in prostate cancer, and how it is involved in tumorogenesis. We aimed to investigate the effect of the SP/NK1R system and the blockage of NK1R with its specific antagonist (aprepitant) on the cellular redox status of the prostate cancer cell line (PC3 and LNCaP). We performed the resazurin assay to evaluate the toxicity of the aprepitant on the PC3 and LNCaP cell lines. The intracellular reactive oxygen species (ROS) level was measured after SP and aprepitant treatment. The alterations of expression and activity of two crucial cellular oxidoreductases, glutaredoxin, and thioredoxin were evaluated by qRT-PCR and commercial kits (ZellBio GmbH), respectively. Our results revealed that SP increased ROS production and decreased the expression and activity of glutaredoxin and thioredoxin. On the other hand, treatment of cells with aprepitant showed reverse results. In conclusion, we found that the SP/NK1R system could promote prostate cancer progression by inducing oxidative stress. In addition, the inhibition of NK1R by aprepitant modulated the effect of the SP/NK1R system on the cellular redox system. Aprepitant might therefore be introduced as a candidate for the treatment of prostate cancer; however, more studies are required to confirm the validation of this hypothesis.

Cancer drug indication approvals in China and the United States: a comparison of approval times and clinical benefit, 2001-2020

Background

Perceived delays in cancer drug approvals have been a major concern for policymakers in China. Policies have been implemented to accelerate the launch of new cancer drugs and indications. This study aimed to assess similarities and differences between China and the United States in the approvals, timing, and clinical benefit evidence of cancer drug indications between 2001 and 2020.

Methods

This study retrospectively identified all cancer drugs and indications approved in both China and the United States from January 1st, 2001 to December 31, 2020, and described differences in approval times as well as in submission and review times. Information on the availability of overall survival benefit evidence by December 31, 2020, was collected. Univariate and multiple logistic regression analyses were used to assess whether evidence of benefit and other factors affected the propensity and timing of approvals of cancer drug indications in China.

Findings

Between 2001 and 2020, 229 indications corresponding to 145 cancer drugs approved in the United States were identified. Of those, 80 indications (34.9%) were also approved in China by the end of 2020. Cancer drug indications were approved in China at a median of 1273.5 days after approval in the United States. The median submission and review time differences for cancer drug indications in China were 1198.0 days and 180.0 days respectively. Submission time differences accounted for most of the approval time differences (p < 0.001). Indications supported by overall survival benefit evidence had shorter median review time differences (145.0 days) than those without such evidence (235.0 days, p = 0.008). Indications with overall survival benefit evidence were 3.94 times more likely to be approved in China compared to those without such evidence (p = 0.001), controlling for approval year, cancer type, and the prevalence of cancer by site.

Interpretation

FDA-approved cancer drug indications demonstrating a survival benefit were more likely to receive approvals in China with shorter regulatory review times compared to indications without such evidence. Given that manufacturer submission times were the main driver of cancer drug approval times in China, factors influencing submission timing should be explored.

Funding

No funding.

Immediate radiotherapy versus observation in patients with node-positive prostate cancer after radical prostatectomy

BACKGROUND

The optimal management of node-positive (pN1) prostate cancer following radical prostatectomy (RP) remains uncertain. Despite randomized evidence, utilization of immediate, life-long androgen deprivation therapy (ADT) remains poor, and recent trials of early salvage radiotherapy included only a minority of pN1 patients. We therefore emulated a hypothetical pragmatic trial of adjuvant radiotherapy versus observation in men with pN1 prostate cancer.

METHODS

Using the RADICALS-RT trial to inform the design of a hypothetical trial, we identified men aged 50-69 years with pT2-3 Rany pN1 M0, pre-treatment PSA < 50 ng/mL prostate cancer in the NCDB from 2006 to 2015 treated with 60-72 Gy of adjuvant RT (aRT) ± ADT within 26 weeks of RP or observation. After estimating a propensity score for receipt of aRT, we estimated absolute and relative treatment effects using stabilized inverse probability of treatment (sIPW) re-weighting.

RESULTS

In total, 3510 patients were included in the study, of whom 587 (17%) received aRT (73% with concurrent ADT). Median follow-up was 40.0 -months, during which 333 deaths occurred. After sIPW re-weighting, baseline characteristics were well-balanced. Adjusted overall survival (OS) was 93% versus 89% at 5-years and 82% versus 79% at 7-years for aRT versus observation (p = 0.11). In IPW-reweighted Cox regression, aRT was associated with a lower risk of all-cause mortality (ACM) than observation, but this did not reach statistical significance (HR 0.70 p = 0.06). In analyses examining heterogeneity of treatment effects, aRT was associated with improved ACM only for men with Gleason 8-10 disease (HR 0.59, p = 0.01), ≥2 positive LNs (HR 0.49, p = 0.04 for 2 positive LNs; HR 0.42, p = 0.01 for ≥3 positive LNs), or negative surgical margins (HR 0.50, p = 0.02).

CONCLUSIONS

In observational analyses designed to emulate a hypothetical target trial of aRT versus observation in pN1 prostate cancer, aRT was associated with improved OS only for men with Gleason 8-10 disease, ≥2 positive LNs, or negative surgical margins.

Myeloid differentiation factor-2/LY96, a potential predictive biomarker of metastasis and poor outcomes in prostate cancer: clinical implications as a potential therapeutic target

Prostate cancer (CaP) is the most diagnosed cancer in males and the second leading cause of cancer deaths. Patients with localized tumors are generally curable. However, no curative treatment exists for patients with advanced and metastatic disease. Therefore, identifying critical proteins involved in the metastatic process would help to develop new therapeutic options for patients with advanced and aggressive CaP. We provide strong evidence that Myeloid differentiation factor-2 (MD2) plays a critical role in metastasis and CaP progression. Analysis of tumor genomic data showed that amplifications of MD2 and increased expression are associated with poor outcomes in patients. Immunohistochemistry analysis of tumor tissues showed a correlation between the expression of MD2 and cancer progression. The Decipher-genomic test validated the potential of MD2 in predicting metastasis. In vitro studies demonstrated that MD2 confers invasiveness by activating MAPK and NF-kB signaling pathways and inducing epithelial-mesenchymal transition. Furthermore, we show that metastatic cells release MD2 (sMD2). We measured serum-sMD2 in patients and found that the level is correlated to disease extent. We determined the significance of MD2 in metastasis in vivo and as a therapeutic target, showing that the molecular and pharmacological targeting of MD2 significantly inhibited metastasis in murine models. We conclude that MD2 predicts metastatic behavior, and serum-MD2 could be studied as a potential non-invasive biomarker for metastasis, whereas MD2 presence on prostate biopsy predicts adverse disease outcome. We suggest MD2-targeted therapies could be developed as potential treatments for aggressive metastatic disease.

[Guidelines for Evaluating Treatment Response Based on Bone Scan for Metastatic Castration-Resistant Prostate Cancer: Prostate Cancer Clinical Trial Working Group 3 Recommendations]

In prostate cancer, the bone is the most common site of metastasis, and it is essential to evaluate metastatic bone lesions to assess the tumor burden and treatment response. Castration-resistant prostate cancer refers to the state wherein the cancer continues to progress despite a significant reduction of the sex hormone level and is associated with frequent distant metastasis. The Prostate Cancer Working Group 3 (PCWG3) released guidelines that aimed to standardize the assessment of treatment effects in castration-resistant prostate cancer using bone scintigraphy. However, these guidelines can be challenging to comprehend and implement in practical settings. The purpose of this review was to provide an overview of a specific image acquisition method and treatment response assessment for bone scintigraphy-based evaluation of bone lesions in metastatic castration-resistant prostate cancer, in accordance with the PCWG3 guidelines.

Lineage plasticity and treatment resistance in prostate cancer: the intersection of genetics, epigenetics, and evolution

Androgen deprivation therapy is a cornerstone of treatment for advanced prostate cancer, and the development of castrate-resistant prostate cancer (CRPC) is the primary cause of prostate cancer-related mortality. While CRPC typically develops through a gain in androgen receptor (AR) signaling, a subset of CRPC will lose reliance on the AR. This process involves genetic, epigenetic, and hormonal changes that promote cellular plasticity, leading to AR-indifferent disease, with neuroendocrine prostate cancer (NEPC) being the quintessential example. NEPC is enriched following treatment with second-generation anti-androgens and exhibits resistance to endocrine therapy. Loss of RB1, TP53, and PTEN expression and MYCN and AURKA amplification appear to be key drivers for NEPC differentiation. Epigenetic modifications also play an important role in the transition to a neuroendocrine phenotype. DNA methylation of specific gene promoters can regulate lineage commitment and differentiation. Histone methylation can suppress AR expression and promote neuroendocrine-specific gene expression. Emerging data suggest that EZH2 is a key regulator of this epigenetic rewiring. Several mechanisms drive AR-dependent castration resistance, notably AR splice variant expression, expression of the adrenal-permissive 3βHSD1 allele, and glucocorticoid receptor expression. Aberrant epigenetic regulation also promotes radioresistance by altering the expression of DNA repair- and cell cycle-related genes. Novel therapies are currently being developed to target these diverse genetic, epigenetic, and hormonal mechanisms promoting lineage plasticity-driven NEPC.

Utilizing metformin to prevent metabolic syndrome due to androgen deprivation therapy (ADT): a randomized phase II study of metformin in non-diabetic men initiating ADT for advanced prostate cancer

BACKGROUND

Androgen deprivation therapy (ADT) can lead to metabolic syndrome (MS) and is implicated in ADT-resistance. Metformin showed antineoplastic activity through mTOR inhibition secondary AMPK-activation.

MATERIALS AND METHODS

To investigate whether metformin mitigated ADT-related MS, we conducted a randomized double-blind phase II trial of metformin 500 mg TID or placebo in non-diabetic patients with biochemically-relapsed or advanced PC due for ADT. Fasting serum glucose, insulin, PSA, metformin, weight and waist circumference (WC) were measured at baseline, week 12 and 28. The primary endpoint was a group of MS metrics. Secondary endpoints include PSA response, safety, serum metformin concentrations and analysis of downstream an mTOR target, phospho-S6-kinase.

RESULTS

36 men were randomized to either metformin or placebo. Mean age was 68.4. Mean weight, WC and insulin levels increased in both arms. At week 12 and 28, no statistical differences in weight, WC or insulin were observed in either arm. No significant difference in percentage of patients with PSA <0.2 at week 28 between metformin (45.5%) vs. placebo (46.7%). Analysis in the metformin-arm showed variable down-regulation of phospho-S6 kinase.

CONCLUSIONS

In our small study, metformin added to ADT did not show a reduced risk of ADT-related MS or differences in PSA response.

Myeloid differentiation factor-2/LY96, a new predictive biomarker of metastasis in prostate cancer: Clinical implications as a potential therapeutic target

Relapsed prostate cancer (CaP), usually treated with androgen deprivation therapy, acquires resistance to develop into lethal metastatic castration-resistant CaP. The cause of resistance remains elusive, and the lack of biomarkers predictive of castration-resistance emergence is a stumbling block in managing the disease. We provide strong evidence that Myeloid differentiation factor-2 (MD2) plays a critical role in metastasis and CaP progression. Analysis of tumor genomic data and IHC of tumors showed a high frequency of MD2 amplification and association with poor overall survival in patients. The Decipher-genomic test validated the potential of MD2 in predicting metastasis. In vitro studies demonstrated that MD2 confers invasiveness by activating MAPK and NF-kB signaling pathways. Furthermore, we show that metastatic cells release MD2 (sMD2). We measured serum-sMD2 in patients and found that the level is correlated to disease extent. We determined the significance of MD2 as a therapeutic target and found that targeting MD2 significantly inhibited metastasis in a murine model. We conclude that MD2 predicts metastatic behavior and serum-MD2 is a non-invasive biomarker for tumor burden, whereas MD2 presence on prostate biopsy predicts adverse disease outcome. We suggest MD2-targeted therapies could be developed as potential treatments for aggressive metastatic disease.

Impact of 18F-fluciclovine PET/CT on plans for androgen deprivation therapy in patients with biochemical recurrence of prostate cancer: data analysis from two prospective clinical trials

INTRODUCTION

Despite early detection and primary therapy improvements, biochemical recurrence (BCR) of prostate cancer remains common. The advent of highly sensitive molecular imaging has facilitated identification of men with limited metastatic disease burden that might be more optimally treated with metastases-directed therapy than with androgen deprivation therapy (ADT). The LOCATE (NCT02680041) and FALCON (NCT02578940) trials assessed the impact of 18F-fluciclovine PET/CT on the management of patients with BCR after curative-intent primary therapy. We performed a secondary analysis of LOCATE and FALCON data to characterize sites of recurrence and management decisions for BCR patients who had an intended management plan including ADT prior to undergoing 18F-fluciclovine PET/CT.

METHODS

Data from 317 LOCATE/FALCON patients who underwent 18F-fluciclovine PET/CT were analyzed and those with a prescan plan for ADT (± another treatment) were selected. 18F-Fluciclovine detection rates were determined at the patient level and for the prostate/prostate bed region, pelvic and extra-pelvic lymph nodes (LN), soft tissues, and bones. The patients' pre- and postscan treatment plans were compared and were stratified by imaging results.

RESULTS

A total of 146 patients had a prescan plan for ADT (60 as monotherapy and 86 in combination with another modality). 18F-Fluciclovine detected lesions in 85 of 146 (58%) patients planned for ADT. Detection rates in the prostate/bed, pelvic LN, extra-pelvic LN, soft tissues and bone were 30%, 25%, 13%, 2.1%, and 13%, respectively. Twenty-five (17%) patients had positivity confined to the prostate/bed, 21 (14%) had 18F-fluciclovine-positive pelvic LN (±prostate/bed) but no other involvement and 39 (27%) had involvement outside the prostate/bed and pelvic LN. Postscan, 93 of 146 (64%) patients had a management change, 55 (59%) of which were to abort ADT. Only 25% of the patients originally planned for ADT monotherapy still had an unaltered plan for ADT monotherapy postscan. Patients with a postscan plan for ADT monotherapy had the most disseminated disease. Disease in the prostate/bed only was most common in those whose plan was altered to abort ADT.

CONCLUSIONS

18F-Fluciclovine-PET/CT influenced management plans for the majority of patients with a prescan plan for ADT. Plans were commonly amended to target salvage therapy for lesions identified with 18F-fluciclovine PET/CT, and consequently likely spared/delayed patients the morbidity associated with ADT.

The Small Molecule Antagonist KCI807 Disrupts Association of the Amino-Terminal Domain of the Androgen Receptor with ELK1 by Modulating the Adjacent DNA Binding Domain

The androgen receptor (AR) is a crucial coactivator of ELK1 for prostate cancer (PCa) growth, associating with ELK1 through two peptide segments (358-457 and 514-557) within the amino-terminal domain (NTD) of AR. The small-molecule antagonist 5-hydroxy-2-(3-hydroxyphenyl)chromen-4-one (KCI807) binds to AR, blocking ELK1 binding and inhibiting PCa growth. We investigated the mode of interaction of KCI807 with AR using systematic mutagenesis coupled with ELK1 coactivation assays, testing polypeptide binding and Raman spectroscopy. In full-length AR, deletion of neither ELK1 binding segment affected sensitivity of residual ELK1 coactivation to KCI807. Although the NTD is sufficient for association of AR with ELK1, interaction of the isolated NTD with ELK1 was insensitive to KCI807. In contrast, coactivation of ELK1 by the AR-V7 splice variant, comprising the NTD and the DNA binding domain (DBD), was sensitive to KCI807. Deletions and point mutations within DBD segment 558-595, adjacent to the NTD, interfered with coactivation of ELK1, and residual ELK1 coactivation by the mutants was insensitive to KCI807. In a glutathione S-transferase pull-down assay, KCI807 inhibited ELK1 binding to an AR polypeptide that included the two ELK1 binding segments and the DBD but did not affect ELK1 binding to a similar AR segment that lacked the sequence downstream of residue 566. Raman spectroscopy detected KCI807-induced conformational change in the DBD. The data point to a putative KCI807 binding pocket within the crystal structure of the DBD and indicate that either mutations or binding of KCI807 at this site will induce conformational changes that disrupt ELK1 binding to the NTD. SIGNIFICANCE STATEMENT: The small-molecule antagonist KCI807 disrupts association of the androgen receptor (AR) with ELK1, serving as a prototype for the development of small molecules for a novel type of therapeutic intervention in drug-resistant prostate cancer. This study provides basic information needed for rational KCI807-based drug design by identifying a putative binding pocket in the DNA binding domain of AR through which KCI807 modulates the amino-terminal domain to inhibit ELK1 binding.

Conventional and new proposals of GnRH therapy for ovarian, breast, and prostatic cancers

For many years, luteinizing hormone-releasing hormone or gonadotropin-releasing hormone (GnRH) analogs have been used to treat androgen or estrogen-dependent tumors. However, emerging evidence shows that the GnRH receptor (GnRH-R) is overexpressed in several cancer cells, including ovarian, endometrial, and prostate cancer cells, suggesting that GnRH analogs could exert direct antitumoral actions in tumoral tissues that express GnRH-R. Another recent approach based on this knowledge was the use of GnRH peptides for developing specific targeted therapies, improving the delivery and accumulation of drugs in tumoral cells, and decreasing most side effects of current treatments. In this review, we discuss the conventional uses of GnRH analogs, together with the recent advances in GnRH-based drug delivery for ovarian, breast, and prostatic cancer cells.

Anti-Cancer Stem-Cell-Targeted Therapies in Prostate Cancer

Prostate cancer (PCa) is the second-most commonly diagnosed cancer in men around the world. It is treated using a risk stratification approach in accordance with the National Comprehensive Cancer Network (NCCN) in the United States. The main treatment options for early PCa include external beam radiation therapy (EBRT), brachytherapy, radical prostatectomy, active surveillance, or a combination approach. In those with advanced disease, androgen deprivation therapy (ADT) is considered as a first-line therapy. However, the majority of cases eventually progress while receiving ADT, leading to castration-resistant prostate cancer (CRPC). The near inevitable progression to CRPC has spurred the recent development of many novel medical treatments using targeted therapies. In this review, we outline the current landscape of stem-cell-targeted therapies for PCa, summarize their mechanisms of action, and discuss avenues of future development.

Urolithin A analog inhibits castration-resistant prostate cancer by targeting the androgen receptor and its variant, androgen receptor-variant 7

We investigated the efficacy of a small molecule ASR-600, an analog of Urolithin A (Uro A), on blocking androgen receptor (AR) and its splice variant AR-variant 7 (AR-V7) signaling in castration-resistant prostate cancer (CRPC). ASR-600 effectively suppressed the growth of AR+ CRPC cells by inhibiting AR and AR-V7 expressions; no effect was seen in AR- CRPC and normal prostate epithelial cells. Biomolecular interaction assays revealed ASR-600 binds to the N-terminal domain of AR, which was further confirmed by immunoblot and subcellular localization studies. Molecular studies suggested that ASR-600 promotes the ubiquitination of AR and AR-V7 resulting in the inhibition of AR signaling. Microsomal and plasma stability studies suggest that ASR-600 is stable, and its oral administration inhibits tumor growth in CRPC xenografted castrated and non-castrated mice. In conclusion, our data suggest that ASR-600 enhances AR ubiquitination in both AR+ and AR-V7 CRPC cells and inhibits their growth in vitro and in vivo models.

Role of multidisciplinary team meetings in implementation of chemohormonal therapy in metastatic prostate cancer in daily practice

BACKGROUND

The recommended treatment for a subset of patients with metastatic prostate cancer (mPC) changed from androgen deprivation therapy (ADT) to combinations with chemotherapy such as docetaxel. Implementation of new evidence from trials is however complex and challenging. We investigated the effect of multidisciplinary team meetings (MDTs) on adopting the newest emerging combination therapy in patients with mPC and assessed the overall survival of chemohormonal therapy in a real-world setting.

METHODS

All mPC patients diagnosed between October 2015 and April 2016 in the Netherlands were identified from the population-based Netherlands Cancer Registry (n = 962). Logistic regression analyses were performed to examine the role of patient- and tumor characteristics, with special emphasis on MDTs, on receiving chemohormonal therapy versus ADT monotherapy. Kaplan-Meier survival curves were used to assess overall survival (OS).

RESULTS

As many patients received ADT monotherapy as chemohormonal therapy (both n = 452). Being discussed in a MDT as patient, younger age, less comorbidities, a better performance status and high-volume disease were significantly associated with receiving chemohormonal therapy compared to ADT monotherapy. After adjustment for these factors, the presence of a MDT was independently associated with the administration of chemohormonal therapy (OR 2.77, 95% CI 1.68-4.59). The 2-year OS was 82.1% (95% CI: 78.5-85.6%) for patients receiving chemohormonal therapy and 59.9% (95% CI: 55.4-64.4%) for patients receiving ADT monotherapy.

CONCLUSION

Being discussed in a MDT is independently associated with the administration of chemohormonal therapy in this group of patients with mPC. This supports the hypothesis that implementation of innovative treatment options is facilitated by an organizational structure with MDTs.

Multifocal glioblastoma and hormone replacement therapy in a transgender female

Background

Glioblastoma multiforme represents approximately 60% of all brain tumors in adults. This malignancy shows a high level of biological and genetic heterogeneity associated with exceptional aggressiveness, leading to poor patient survival. One of the less common presentations is the appearance of primary multifocal lesions, which are linked with a worse prognosis. Among the multiple triggering factors in glioma progression, the administration of sex steroids and their analogs has been studied, but their role remains unclear to date.

Case Description

A 43-year-old transgender woman who has a personal pathological history of receiving intramuscular (IM) hormone treatment for 27 years based on algestone/estradiol 150 mg/10 mg/mL. Three months ago, the patient suddenly experienced hemiplegia and hemiparesis in her right lower extremity, followed by a myoclonic focal epileptic seizure, vertigo, and a right frontal headache with a visual analog scale of 10/10. Magnetic resonance imaging images revealed an intra-axial mass with poorly defined, heterogeneous borders, and thick borders with perilesional edema in the left parietal lobe, as well as a rounded hypodense image with well-defined walls in the right internal capsule. The tumor was resected, and samples were sent to the pathology department, which confirmed the diagnosis of wild-type glioblastoma.

Conclusion

This report identifies prolonged use of steroid-based hormone replacement therapy as the only predisposing factor in the oncogenesis of multifocal glioblastoma. It is an example that highlights the importance for physicians not to consider pathologies related to the human immunodeficiency virus rather than neoplasms in transgender patients in view of progressive neurological deterioration.

Targeting aldehyde dehydrogenase for prostate cancer therapies

Prostate cancer (PCa) is the most common cancer in men in the United States. About 10 – 20% of PCa progress to castration-resistant PCa (CRPC), which is accompanied by metastasis and therapeutic resistance. Aldehyde dehydrogenase (ALDH) is famous as a marker of cancer stem-like cells in different cancer types, including PCa. Generally, ALDHs catalyze aldehyde oxidation into less toxic carboxylic acids and give cancers a survival advantage by reducing oxidative stress caused by aldehyde accumulation. In PCa, the expression of ALDHs is associated with a higher tumor stage and more lymph node metastasis. Functionally, increased ALDH activity makes PCa cells gain more capabilities in self-renewal and metastasis and reduces the sensitivity to castration and radiotherapy. Therefore, it is promising to target ALDH or ALDH^high cells to eradicate PCa. However, challenges remain in moving the ALDH inhibitors to PCa therapy, potentially due to the toxicity of pan-ALDH inhibitors, the redundancy of ALDH isoforms, and the lack of explicit understanding of the metabolic signaling transduction details. For targeting PCa stem-like cells (PCSCs), different regulators have been revealed in ALDH^high cells to control cell proliferation and tumorigenicity. ALDH rewires essential signaling transduction in PCa cells. It has been shown that ALDHs produce retinoic acid (RA), bind with androgen, and modulate diverse signaling. This review summarizes and discusses the pathways directly modulated by ALDHs, the crucial regulators that control the activities of ALDH^high PCSCs, and the recent progress of ALDH targeted therapies in PCa. These efforts will provide insight into improving ALDH-targeted treatment.

Impact of treatment on elder-relevant physical function and quality of life outcomes in older adults with metastatic castration-resistant prostate cancer

INTRODUCTION

Understanding physical function (PF) and quality of life (QoL) treatment effects are important in treatment decision-making for older adults with cancer. However, data are limited for older men with metastatic castration-resistant prostate cancer (mCRPC). We evaluated the effects of treatment on PF and QoL in older men with mCRPC.

MATERIALS AND METHODS

Men aged 65+ with mCRPC were enrolled in this multicenter prospective observational study. PF measures included instrumental activities of daily living, grip strength, chair stands, and gait speed. QoL measures included fatigue, pain, mood, and Functional Assessment of Cancer Therapy (FACT)-General total and sub-scale scores. Outcomes were collected at baseline, three, and six months. Linear mixed effects regression models were used to examine PF and QoL differences over time across various treatment cohorts.

RESULTS

We enrolled 198 men starting chemotherapy (n = 71), abiraterone (n = 37), enzalutamide (n = 67), or radium-223 (n = 23). At baseline, men starting chemotherapy had worse measures of PF, QoL, pain, and mood than the other groups. Over time, all PF measures remained stable, pain improved, but functional wellbeing (FWB) and mood worsened significantly for all cohorts. However, change over time in all outcomes was not appreciably different between treatment cohorts. Worst-case sensitivity analyses identified attrition (ranging from 22 to 42% by six months) as a major limitation of our study, particularly for the radium-223 cohort.

DISCUSSION

FWB and mood were most prone to deterioration over time, whereas pain improved with treatment. Although patients initiating chemotherapy had worse baseline PF and QoL, chemotherapy was not associated with significantly greater worsening over time compared to other common therapies for mCRPC. These findings may assist in treatment discussions with patients. However, given the modest sample size, attrition, and timeframe of follow-up, the impact of treatment on PF and QoL outcomes in this setting requires further study, particularly for radium-223.

Bone Health Management in the Continuum of Prostate Cancer Disease

Prostate cancer (PCa) is the second-leading cause of cancer-related deaths in men. PCa cells require androgen receptor (AR) signaling for their growth and survival. Androgen deprivation therapy (ADT) is the preferred treatment for patients with locally advanced and metastatic PCa disease. Despite their initial response to androgen blockade, most patients eventually will develop metastatic castration-resistant prostate cancer (mCRPC). Bone metastases are common in men with mCRPC, occurring in 30% of patients within 2 years of castration resistance and in >90% of patients over the course of the disease. Patients with mCRPC-induced bone metastasis develop lesions throughout their skeleton; the 5-year survival rate for these patients is 47%. Bone-metastasis-induced early changes in the bone that proceed the osteoblastic response in the bone matrix are monitored and detected via modern magnetic resonance and PET/CT imaging technologies. Various treatment options, such as targeting osteolytic metastasis with bisphosphonates, prednisone, dexamethasone, denosumab, immunotherapy, external beam radiation therapy, radiopharmaceuticals, surgery, and pain medications are employed to treat prostate-cancer-induced bone metastasis and manage bone health. However, these diagnostics and treatment options are not very accurate nor efficient enough to treat bone metastases and manage bone health. In this review, we present the pathogenesis of PCa-induced bone metastasis, its deleterious impacts on vital organs, the impact of metastatic PCa on bone health, treatment interventions for bone metastasis and management of bone- and skeletal-related events, and possible current and future therapeutic options for bone management in the continuum of prostate cancer disease.

Emerging Biomarker-Guided Therapies in Prostate Cancer

Prostate cancer remains one of the leading causes of cancer death in men worldwide. In the past decade, several new treatments for advanced prostate cancer have been approved. With a wide variety of available drugs, including cytotoxic agents, androgen receptor axis-targeted therapies, and alpha-emitting radiation therapy, identifying their optimal sequencing remains a challenge. Progress in the understanding of the biology of prostate cancer has provided an opportunity for a more refined and personalized treatment selection process. With the advancement of molecular sequencing techniques, genomic precision through the identification of potential treatment targets and predictive biomarkers has been rapidly evolving. In this review, we discussed biomarker-driven treatments for advanced prostate cancer. First, we presented predictive biomarkers for established, global standard treatments for advanced diseases, such as chemotherapy and androgen receptor axis-targeted agents. We also discussed targeted agents with recent approval for special populations, such as poly ADP ribose polymerase (PARP) inhibitors in patients with metastatic castrate-resistant prostate cancer with homologous recombination repair-deficient tumors, pembrolizumab in patients with high levels of microsatellite instability or high tumor mutational burden, and prostate-specific membrane antigen (PSMA) directed radioligand theragnostic treatment for PSMA expressing tumors. Additionally, we discussed evolving treatments, such as cancer vaccines, chimeric antigen receptor T-cells (CAR-T), Bispecific T-cell engagers (BiTEs), other targeted agents such as AKT inhibitors, and various combination treatments. In summary, advances in molecular genetics have begun to propel personalized medicine forward in the management of advanced prostate cancer, allowing for a more precise, biomarker-driven treatment selection with the goal of improving overall efficacy.

Identification of ELK1 interacting peptide segments in the androgen receptor

Prostate cancer (PCa) growth requires tethering of the androgen receptor (AR) to chromatin by the ETS domain transcription factor ELK1 to coactivate critical cell proliferation genes. Disruption of the ELK1-AR complex is a validated potential means of therapeutic intervention in PCa. AR associates with ELK1 by co-opting its two ERK docking sites, through the amino-terminal domain (A/B domain) of AR. Using a mammalian two-hybrid assay, we have now functionally mapped amino acids within the peptide segments 358-457 and 514-557 in the A/B domain as required for association with ELK1. The mapping data was validated by GST (glutathione S-transferase)-pulldown and BRET (bioluminescence resonance energy transfer) assays. Comparison of the relative contributions of the interacting motifs/segments in ELK1 and AR to coactivation of ELK1 by AR suggested a parallel mode of binding of AR and ELK1 polypeptides. Growth of PCa cells was partially inhibited by deletion of the upstream segment in AR and nearly fully inhibited by deletion of the downstream segment. Our studies have identified two peptide segments in AR that mediate functional association of AR with its two docking sites in ELK1. Identification of the ELK1 recognition sites in AR should enable further structural studies of the ELK1-AR interaction and rational design of small molecule drugs to disrupt this interaction.

Androgen-targeting therapeutics mitigate the adverse effect of GnRH agonist on the risk of neurodegenerative disease in men treated for prostate cancer

BACKGROUND

Prostate cancer and multiple neurodegenerative diseases (NDD) share an age-associated pattern of onset. Therapy of prostate cancer is known to impact cognitive function. The objective of this study was to determine the impact of multiple classes of androgen-targeting therapeutics (ATT) on the risk of NDD.

METHODS

A retrospective cohort study of men aged 45 and older with prostate within the US-based Mariner claims data set between January 1 and 27, 2021. A propensity score approach was used to minimize measured and unmeasured selection bias. Disease risk was determined using Kaplan-Meier survival analyses.

RESULTS

Of the 1,798,648 men with prostate cancer, 209,722 met inclusion criteria. Mean (SD) follow-up was 6.4 (1.8) years. In the propensity score-matched population, exposure to ATT was associated with a minimal increase in NDD incidence (relative risk [RR], 1.07; 95% CI, 1.05-1.10; p < 0.001). However, GnRH agonists alone were associated with significantly increased NDD risk (RR, 1.47; 95% CI, 1.30-1.66; p <0.001). Abiraterone, commonly administered with GnRH agonists and low-dose prednisone, was associated with a significantly decreased risk (RR, 0.77; 95% CI, 0.68-0.87; p < 0.001) of any NDD.

CONCLUSIONS

Among patients with prostate cancer, GnRH agonist exposure was associated with an increased NDD risk. Abiraterone acetate reduced the risks of Alzheimer's disease and Parkinson's disease conferred by GnRH agonists, whereas the risk for ALS was reduced by androgen receptor inhibitors. Outcomes of these analyses contribute to addressing controversies in the field and indicate that GnRH agonism may be a predictable instigator of risk for NDD with opportunities for risk mitigation in combination with another ATT.

Targeting the androgen receptor signaling pathway in advanced prostate cancer

DISCLAIMER

In an effort to expedite the publication of articles related to the COVID-19 pandemic, AJHP is posting these manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time.

PURPOSE

This article summarizes current androgen receptor (AR)-directed therapies that have received regulatory approval for the treatment of advanced prostate adenocarcinoma (herein referred to as prostate cancer, PC).

SUMMARY

PC is an androgen-dependent malignancy in which ligands including testosterone and dihydrotestosterone bind to AR, initiating androgen-AR complex translocation to the nucleus followed by AR-mediated transcription of target genes. Androgen deprivation therapy (ADT), including gonadotropin hormone-releasing hormone (GnRH) agonists with or without AR antagonists (antiandrogens), GnRH antagonists, or bilateral orchiectomy, forms the backbone of treatment for patients with metastatic castration-naive PC and/or castration-resistant PC (CRPC). ADT is also an option for high-risk, early-stage PC after prostatectomy and/or radiation. While ADT is often very effective as initial therapy, resistance ultimately develops despite suppression of gonadal and/or adrenal androgens, leading to CRCPC, which is characterized by mechanisms such as reactivation of the AR signaling pathway, AR overexpression, and gene mutations in the ligand-binding domain of AR that lead to disease progression, resulting in increased symptom burden and ultimately death. However, disease in patients with CRPC is still dependent on androgen signaling, and these patients continue on ADT to maintain a castrate level of serum testosterone. Novel hormonal therapies including agents that target AR directly (eg, AR antagonists) are often added to ADT in this setting. Targeting the AR signaling pathway led to the development of second-generation AR antagonists, examples of which include enzalutamide, apalutamide, and darolutamide. These agents do not exhibit partial agonism or possess a higher affinity for AR and are not postulated to improve survival outcomes relative to their first-generation counterparts for patients with CRPC. Lastly, the emergence of ADT, including second-generation AR antagonists, has led to the development of supportive care for treatment-related adverse effects.

CONCLUSION

Major advances have been made in targeting the AR signaling pathway in patients with advanced PC. Further studies are warranted to identify the optimal sequencing of therapies to maximize treatment benefit. Mitigation of treatment-related adverse effects presents new opportunities to advance clinical pharmacy practice.

A radiologist’s guide to novel anticancer therapies in the era of precision medicine

Novel anticancer agents have replaced conventional chemotherapy as first line agents for many cancers, with continued new and expanding indications. Small molecule inhibitors act on cell surface or intracellular targets and prevent the downstream signaling that would otherwise permit tumor growth and spread. Anticancer antibodies can be directed against growth factors or may be immunotherapeutic agents. The latter act by inhibiting mechanisms that cancer cells use to evade the immune system. Hormonal agents act by decreasing levels of hormones that are necessary for the growth of certain cancer cells. Cancer therapy protocols often include novel anticancer agents and conventional chemotherapy used successively or in combination, in order to maximize survival and minimize morbidity. A working knowledge of anti-cancer drug classification will aid the radiologist in assessing response on imaging.

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Novel anticancer agents include small molecule inhibitors, antibodies and hormones.

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These agents are predominantly cytostatic and inhibit factors that provide a survival advantage to tumor cells.

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Modern cancer therapy employs a combination of novel anticancer agents and conventional chemotherapy.

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It is essential for radiologists to have a broad understanding of these agents and their mechanisms of action.

Risk of Fatigue and Anemia in Patients With Prostate Cancer Treated With Novel Oral Anti-androgens: A Meta-Analysis of Randomized Controlled Trials

Novel oral anti-androgens (NOAAs) represent a new class of drugs that are being approved for prostate cancer. However, fatigue and anemia are among the most common treatment-related symptoms. Hence, we conducted a meta-analysis of randomized controlled trials (RCTs) to investigate the relative risks (RRs) of fatigue and anemia associated with NOAAs. PubMed, Cochrane, EMBASE, and abstracts presented at the annual meeting of the American Society of Clinical Oncology and European Society of Clinical Oncology were searched for phase III and V RCTs of NOAAs from January 2000 to March 2020. Safety profile from each selected study was evaluated for all-grade and high-grade fatigue and anemia adverse events. The RRs with 95% confidence intervals (95% CIs) were calculated using random-effects for all-grade and high-grade events. Our analysis involved 15 RCTs, including 16,795 patients. Overall, 9,177 patients were treated with NOAAs in the experimental arm, whereas 7,095 received a standard of care in the control arm. The RR of all-grade and high-grade fatigue was 1.26 (95% CI 1.15-1.38) and 1.24 (95% CI 0.83-1.84), and that of all-grade and high-grade anemia was 0.81 (95% CI 0.77-1.19) and 0.81 (95% CI 0.61-1.06), respectively. Our findings suggest that NOAAs are associated with an increased risk of fatigue but decreased risk of anemia. Patients should be frequently monitored to identify adverse events to improve oncological outcomes and optimize the overall treatment efficacy and safety. Not all the RCTs addressed fatigue and anemia simultaneously as side effects of NOAA treatment.

Biomarkers for Treatment Response in Advanced Prostate Cancer

Simple Summary

Prostate cancer is a leading cause of cancer-related death among males. Many treatments are available to manage the disease, but despite this, ultimately advanced prostate cancer is incurable and fatal. In order to improve survival and minimize side effects from these various treatments, the treatments need to be given in an optimal sequence or combination. This optimal use of therapies must be individualized, and biomarkers can be used for these decisions. Biomarkers can be useful in predicting whether a patient will respond to a treatment option and may help avoid use of therapies that are not expected to be effective. Many biomarkers are already in clinical use while many others are currently being investigated and may become part of clinical practice in future. In this review, we discuss both established and novel biomarkers with a role in management of advanced prostate cancer.

Abstract

Multiple treatment options with different mechanisms of action are currently available for the management of metastatic prostate cancer. However, the optimal use of these therapies—specifically, the sequencing of therapies—is not well defined. In order to obtain the best clinical outcomes, patients need to be treated with the therapies that are most likely to provide benefit and avoid toxic therapies that are unlikely to be effective. Ideally, predictive biomarkers that allow for the selection of the therapies most likely to be of benefit would be employed for each treatment decision. In practice, biomarkers including tumor molecular sequencing, circulating tumor DNA, circulating tumor cell enumeration and androgen receptor characteristics, and tumor cell surface expression (PSMA), all may have a role in therapy selection. In this review, we define the established prognostic and predictive biomarkers for therapy in advanced prostate cancer and explore emerging biomarkers.

Radiomics for Identification and Prediction in Metastatic Prostate Cancer: A Review of Studies

Metastatic Prostate Cancer (mPCa) is associated with a poor patient prognosis. mPCa spreads throughout the body, often to bones, with spatial and temporal variations that make the clinical management of the disease difficult. The evolution of the disease leads to spatial heterogeneity that is extremely difficult to characterise with solid biopsies. Imaging provides the opportunity to quantify disease spread. Advanced image analytics methods, including radiomics, offer the opportunity to characterise heterogeneity beyond what can be achieved with simple assessment. Radiomics analysis has the potential to yield useful quantitative imaging biomarkers that can improve the early detection of mPCa, predict disease progression, assess response, and potentially inform the choice of treatment procedures. Traditional radiomics analysis involves modelling with hand-crafted features designed using significant domain knowledge. On the other hand, artificial intelligence techniques such as deep learning can facilitate end-to-end automated feature extraction and model generation with minimal human intervention. Radiomics models have the potential to become vital pieces in the oncology workflow, however, the current limitations of the field, such as limited reproducibility, are impeding their translation into clinical practice. This review provides an overview of the radiomics methodology, detailing critical aspects affecting the reproducibility of features, and providing examples of how artificial intelligence techniques can be incorporated into the workflow. The current landscape of publications utilising radiomics methods in the assessment and treatment of mPCa are surveyed and reviewed. Associated studies have incorporated information from multiple imaging modalities, including bone scintigraphy, CT, PET with varying tracers, multiparametric MRI together with clinical covariates, spanning the prediction of progression through to overall survival in varying cohorts. The methodological quality of each study is quantified using the radiomics quality score. Multiple deficits were identified, with the lack of prospective design and external validation highlighted as major impediments to clinical translation. These results inform some recommendations for future directions of the field.

Case report: A rare occurrence of a huge mediastinal mass from disseminated prostate carcinoma

Background

Prostatic carcinoma is the commonest malignancy among men. It usually metastasizes to the spine and regional lymph nodes. However, it is extremely rare for it to metastasize to the mediastinum.

Case presentation

An elderly man presented to us with progressive onset of bilateral lower limb weakness which was associated with thoracic radiculopathy and urinary incontinence. An urgent magnetic resonance imaging (MRI) of the spine showed severe cord compression with enlarged prostate and superior mediastinal mass. A computed tomography (CT) guided biopsy of the mediastinal mass was suggestive of prostatic malignancy. An emergency posterior instrumentation and fusion (PSIF) in prone position was successfully done. Histopathological examination of the spine showed malignant glandular tissues, suggestive of prostate.

Discussion

A huge mediastinal mass can compromise the cardiorespiratory system and is very challenging for the anaesthetist to safely secure the airway for surgical procedures. Androgen deprivation therapy (ADT) for patients with metastatic prostatic carcinoma can be achieved either by medical castration or with bilateral orchidectomy.

Conclusion

It is extremely uncommon for a prostatic carcinoma to metastasize to the mediastinum. Patients with a huge mediastinal mass possess risks of cardiorespiratory collapse perioperatively. Chemoradiotherapy and androgen deprivation therapy (ADT) can be utilized for metastatic prostatic carcinoma with good outcomes.

Real-world Cardiovascular Outcomes Associated With Degarelix vs Leuprolide for Prostate Cancer Treatment

IMPORTANCE

With a growing interest in the use of real-world evidence for regulatory decision-making, it is important to understand whether real-world data can be used to emulate the results of randomized clinical trials.

OBJECTIVE

To use electronic health record and administrative claims data to emulate the ongoing PRONOUNCE trial (A Trial Comparing Cardiovascular Safety of Degarelix Versus Leuprolide in Patients With Advanced Prostate Cancer and Cardiovascular Disease).

DESIGN, SETTING, AND PARTICIPANTS

This retrospective, propensity-matched cohort study included adult men with a diagnosis of prostate cancer and cardiovascular disease who initiated either degarelix or leuprolide between December 24, 2008, and June 30, 2019. Participants were commercially insured individuals and Medicare Advantage beneficiaries included in a large US administrative claims database.

EXPOSURES

Degarelix or leuprolide.

MAIN OUTCOMES AND MEASURES

The primary end point was time to first occurrence of a major adverse cardiovascular event (MACE), defined as death due to any cause, myocardial infarction, or stroke, analogous to the PRONOUNCE trial. Secondary end points were time to death due to any cause, myocardial infarction, stroke, and angina. Cox proportional hazards regression was used to evaluate primary and secondary end points.

RESULTS

A total of 32 172 men initiated degarelix or leuprolide for prostate cancer; of them, 9490 (29.5%) had cardiovascular disease, and 7800 (24.2%) met the PRONOUNCE trial eligibility criteria and were included in this study. Overall, 165 participants (2.1%) were Asian, 1390 (17.8%) were Black, 663 (8.5%) were Hispanic, and 5258 (67.4%) were White. The mean (SD) age was 74.4 (7.4) years. Among 2226 propensity score-matched patients, no significant difference was observed in the risk of MACE for patients taking degarelix vs those taking leuprolide (10.18 vs 8.60 events per 100 person-years; hazard ratio [HR], 1.18; 95% CI, 0.86-1.61). Degarelix was associated with a higher risk of death from any cause (HR, 1.48; 95% CI, 1.01-2.18) but not of myocardial infarction (HR, 1.16; 95% CI, 0.60-2.25), stroke (HR, 0.92; 95% CI, 0.45-1.85), or angina (HR, 1.36; 95% CI, 0.43-4.27).

CONCLUSIONS AND RELEVANCE

In this emulation of a clinical trial of men with cardiovascular disease undergoing treatment for prostate cancer, degarelix was not associated with a lower risk of cardiovascular events than leuprolide. Comparison of these data with PRONOUNCE trial results, when published, will help enhance our understanding of the appropriate role of using real-world data to emulate clinical trials.

Combination Therapy of Metastatic Castration-Recurrent Prostate Cancer: Hyaluronic Acid Decorated, Cabazitaxel-Prodrug and Orlistat Co-Loaded Nano-System

Purpose

Prostate cancer (PCa) is the second leading cause of cancer-related death among men in developed countries. Cabazitaxel (CBZ) is recommended as one of the most active chemotherapy agents for PCa. This study aimed to develop a hyaluronic acid (HA) decorated, cabazitaxel-prodrug (HA-CBZ) and orlistat (ORL) co-loaded nano-system against the prostate cancer in vitro and in vivo.

Methods

Cabazitaxel-prodrug was firstly synthesized by conjugating HA with CBZ through the formation of ester bonds. HA contained ORL and CBZ prodrug co-loaded lipid-polymer hybrid nanoparticles (ORL/HA-CBZ/LPNs) were constructed and characterized in terms of particle size, zeta potential, drug loading capacity and stability. The antitumor efficiency and systemic toxicity of LPNs were evaluated in vitro and in vivo.

Results

The resulting ORL/HA-CBZ/LPNs were 150.9 nm in particle size with narrow distribution and high entrapment efficiency. The minimum combination index of 0.57 was found at a drug ratio of 1:2 (ORL:HA-CBZ, w/w) in the drug co-loaded formulations, indicating the strongest synergism effect. ORL/HA-CBZ/LPNs demonstrated an enhanced in vitro and in vivo antitumor effect compared with single drug loaded LPNs and free drug formulations.

Conclusion

ORL/HA-CBZ/LPNs showed remarkable synergism cytotoxicity and the best tumor inhibition efficiency in mice with negligible systemic toxicity. ORL/HA-CBZ/LPNs can be highly useful for targeted prostate cancer therapy.

A phase 3 randomised study of enzalutamide plus leuprolide and enzalutamide monotherapy in high-risk non-metastatic hormone-sensitive prostate cancer with rising PSA after local therapy: EMBARK study design

INTRODUCTION

Limited data from controlled clinical trials are available for men who experience biochemical recurrence after definitive therapy for prostate cancer. In the absence of overt metastases, patients with non-metastatic castration-sensitive prostate cancer (nmCSPC) often receive androgen deprivation therapy (ADT). There is no standard-of-care consensus on optimal ADT timing, although most men are treated prior to metastases, especially those with high-risk features (Gleason score 8-10 or prostate-specific antigen doubling time (PSADT) <9-12 months). Given data that ADT plus novel hormonal agents improve survival in men with metastatic CSPC, there is a desire to evaluate these agents earlier in the disease course. The main objective of EMBARK is the comparative assessment of enzalutamide plus leuprolide (luteinising hormone-releasing hormone agonist (LHRHa)) or enzalutamide monotherapy versus monotherapy LHRHa to improve metastasis-free survival (MFS) in patients with high-risk nmCSPC PSA recurrence after definitive therapy.

METHODS AND ANALYSIS

EMBARK is a randomised, phase 3 study of high-risk patients with nmCSPC, a PSADT of ≤9 months and a screening PSA of ≥2 ng/mL above the nadir after radiotherapy (RT) or ≥1 ng/mL after radical prostatectomy (RP) with or without postoperative RT. Men (n=1050) are randomised 1:1:1 to enzalutamide 160 mg/day plus LHRHa or placebo plus LHRHa (double-blind arms) or enzalutamide monotherapy (open-label arm). Treatment is suspended at week 37 if PSA concentrations are <0.2 ng/mL and reinstated if levels rise to ≥2.0 ng/mL with RP or ≥5.0 ng/mL without RP. Patients with PSA ≥0.2 ng/mL at week 37 continue until treatment discontinuation criteria are met. The primary endpoint is MFS comparing enzalutamide plus LHRHa versus placebo plus LHRHa.

ETHICS AND DISSEMINATION

The study is conducted under the guiding principles of the World Medical Association Declaration of Helsinki. The results will be disseminated at research conferences and in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT02319837.

Local Therapies in Oligometastatic and Oligoprogressive Prostate Cancer

Oligometastatic disease was originally defined by Hellman and Weichselbaum as an intermediate-state existing between locally confined and widely disseminated malignancy, whose natural history could be positively impacted with systemic and importantly local therapies such as radiation. Currently oligometastatic prostate cancer (OPCa) is defined clinically by lesion enumeration and several subgroups exist: de novo (synchronous) oligometastatic disease present at initial diagnosis, oligorecurrent (metachronous) disease arising after definitive therapy to the prostate, and oligoprogressive disease where isolated lesions progress in a background of otherwise stable disease. In this review we highlight current knowledge and the potential future of local therapies, such as radiation to the primary prostate and metastasis-directed therapy (MDT), in the disease management of OPCa for all 3 subgroups. In addition, we examine more recent studies classifying the patterns of failure and natural history of OPCa following treatment with local therapies. Finally, while current clinical definitions of OPCa dominate, we introduce studies attempting to elucidate a more biological definition of OPCa to allow for improved selection of patients to treat with local therapies and to better inform precision combination approaches with systemic therapy.

Basic Science and Molecular Genetics of Prostate Cancer Aggressiveness

Androgen receptor function, tumor cell plasticity, loss of tumor suppressors, and defects in DNA repair genes affect aggressive features of prostate cancer. Prostate cancer development, progression, and aggressive behavior are often attributable to function of the androgen receptor. Tumor cell plasticity, neuroendocrine features, and loss of tumor suppressors lend aggressive behavior to prostate cancer cells. DNA repair defects have ramifications for prostate cancer cell behavior.

Stunning Response with Low-Dose Enzalutamide after Abiraterone Acetate Failure in a Patient Diagnosed with Metastatic Castration-Resistant Prostate Cancer: A Case Report

We report a case of an elderly patient with metastatic castration-resistant prostate cancer, initially treated with abiraterone acetate (1,000 mg/day) combined with LH-RH antagonist, prednisone (10 mg/day), and zoledronic acid to manage bone metastases. In consideration of his poor performance status, radiological and biochemical progression of the disease, we decided to switch abiraterone to enzalutamide (160 mg/day). Due to adverse events, we reduced enzalutamide to a dose of 80 mg/day. Currently, the disease is under control despite the use of a low dose of enzalutamide.

Radiotherapy in the Management of Metastatic Hormone-Sensitive Prostate Cancer: What Is the Standard of Care?

Systemic therapy has historically been the backbone of treatment for patients with metastatic disease. However, recent evidence suggests metastasis-directed therapy in those with oligometastatic disease (≤5 lesions) may improve progression-free and overall survival. Within prostate cancer-specific cohorts, metastasis-directed therapy also appears to delay the time to initiation of androgen deprivation therapy while also generally being associated with a mild toxicity profile and has thus garnered interest as a means to delay systemic therapy. Here we review the evidence surrounding the use of radiation therapy to metastatic sites in patients with metastatic hormone-sensitive prostate cancer.

Oligometastatic and Oligoprogression Disease and Local Therapies in Prostate Cancer

Our understanding of metastatic disease is rapidly advancing, with recent evidence supporting an oligometastatic state currently defined by patients having a limited (typically ≤5) number of metastatic deposits. The optimal management of these patients is also shifting toward increased integration of local therapies, with emerging evidence suggesting metastasis-directed therapy can improve overall survival. Additionally, the use of stereotactic ablative radiation therapy within castration-sensitive oligometastatic prostate cancer cohorts appears to forestall the need to initiate systemic therapy, which has unfavorable side effect profiles, such as androgen deprivation therapy, while itself being associated with little toxicity. We review the literature surrounding the use of metastasis-directed therapy in the treatment of oligometastatic prostate cancer by reviewing the evidence for its use within 3 subgroups: de novo synchronous, oligorecurrent, and oligoprogressive disease.

Overall Survival After Systemic Treatment in High-volume Versus Low-volume Metastatic Hormone-sensitive Prostate Cancer: Systematic Review and Network Meta-analysis

CONTEXT

Novel prospective randomized controlled observations addressing combination therapy in metastatic hormone-sensitive prostate cancer (mHSPC) have demonstrated promising overall survival (OS) outcomes.

OBJECTIVE

To compare these novel findings and systematically review and address them within formal network meta-analyses (NMAs) that include observations from other prospective randomized controlled trials (RCTs).

EVIDENCE ACQUISITION

First, we focused on abiraterone, enzalutamide, apalutamide, and docetaxel effects on OS in mHSPC using the PRISMA methodology. PubMed and abstracts identified prospective RCTs in first-line mHSPC. Second, we focused on mature studies that reached median OS and tested OS between abiraterone and docetaxel with tumor burden stratification.

EVIDENCE SYNTHESIS

The first part included seven studies (n = 6639) and the second part, five studies (n = 4462). In the first part, abiraterone ranked first for high-volume mHSPC. Conversely, enzalutamide ranked first for low-volume mHSPC. In the second part, abiraterone treatment in high-volume mHSPC resulted in median OS of 50.1 mo and exceeded that with docetaxel (45.9 mo) and ADT alone (34.0 mo). Docetaxel treatment in low volume mHSPC resulted in median OS of 69.5 mo versus 67.7 mo with ADT alone.

CONCLUSIONS

In conventional NMA that relied on conventional hazard ratios, differences were identified with respect to the relative efficacy of the combination therapies examined; abiraterone dominated the alternatives in high-volume mHSPC. In part two, which relied on trials for which median OS is available, comparison of abiraterone versus docetaxel revealed a 4-mo difference in OS in high-volume mHSPC. Conventional NMA may have overestimated the importance of treatment efficacy instead of focusing on median OS duration, which might represent a more important clinical endpoint.

PATIENT SUMMARY

We reviewed studies on hormonal treatments and chemotherapy used for prostate cancer that has spread outside the prostate gland (metastatic prostate cancer, mPC). We found that the best overall survival was with the hormone agents abiraterone in high-volume mPC and enzalutamide in low-volume mPC. In comparison to the chemotherapy drug docetaxel, median overall survival with abiraterone was 4 months longer among patients with mPC.

Initial Management of Noncastrate Advanced, Recurrent, or Metastatic Prostate Cancer: ASCO Guideline Update

PURPOSE

Update all preceding ASCO guidelines on initial hormonal management of noncastrate advanced, recurrent, or metastatic prostate cancer.

METHODS

The Expert Panel based recommendations on a systematic literature review. Recommendations were approved by the Expert Panel and the ASCO Clinical Practice Guidelines Committee.

RESULTS

Four clinical practice guidelines, one clinical practice guidelines endorsement, 19 systematic reviews with or without meta-analyses, 47 phase III randomized controlled trials, nine cohort studies, and two review papers informed the guideline update.

RECOMMENDATIONS

Docetaxel, abiraterone, enzalutamide, or apalutamide, each when administered with androgen deprivation therapy (ADT), represent four separate standards of care for noncastrate metastatic prostate cancer. Currently, the use of any of these agents in any particular combination or series cannot be recommended. ADT plus docetaxel, abiraterone, enzalutamide, or apalutamide should be offered to men with metastatic noncastrate prostate cancer, including those who received prior therapies, but have not yet progressed. The combination of ADT plus abiraterone and prednisolone should be considered for men with noncastrate locally advanced nonmetastatic prostate cancer who have undergone radiotherapy, rather than castration monotherapy. Immediate ADT may be offered to men who initially present with noncastrate locally advanced nonmetastatic disease who have not undergone previous local treatment and are unwilling or unable to undergo radiotherapy. Intermittent ADT may be offered to men with high-risk biochemically recurrent nonmetastatic prostate cancer. Active surveillance may be offered to men with low-risk biochemically recurrent nonmetastatic prostate cancer. The panel does not support use of either micronized abiraterone acetate or the 250 mg dose of abiraterone with a low-fat breakfast in the noncastrate setting at this time.Additional information is available at www.asco.org/genitourinary-cancer-guidelines.

The circadian cryptochrome, CRY1, is a pro-tumorigenic factor that rhythmically modulates DNA repair

Mechanisms regulating DNA repair processes remain incompletely defined. Here, the circadian factor CRY1, an evolutionally conserved transcriptional coregulator, is identified as a tumor specific regulator of DNA repair. Key findings demonstrate that CRY1 expression is androgen-responsive and associates with poor outcome in prostate cancer. Functional studies and first-in-field mapping of the CRY1 cistrome and transcriptome reveal that CRY1 regulates DNA repair and the G2/M transition. DNA damage stabilizes CRY1 in cancer (in vitro, in vivo, and human tumors ex vivo), which proves critical for efficient DNA repair. Further mechanistic investigation shows that stabilized CRY1 temporally regulates expression of genes required for homologous recombination. Collectively, these findings reveal that CRY1 is hormone-induced in tumors, is further stabilized by genomic insult, and promotes DNA repair and cell survival through temporal transcriptional regulation. These studies identify the circadian factor CRY1 as pro-tumorigenic and nominate CRY1 as a new therapeutic target.

Cryptochrome 1 (CRY1) is a transcriptional coregulator associated with the circadian clock. Here the authors reveal that CRY1 is hormone-regulated, stabilized by genomic insult, and promotes DNA repair and cell survival through temporal transcriptional regulation.

Long-term follow-up comparing salvage radiation therapy and androgen-deprivation therapy for biochemical recurrence after radical prostatectomy

BACKGROUND

The salvage treatments for biochemical recurrence (BCR) include local external beam radiation therapy (RT) and systemic androgen-deprivation therapy (ADT).

METHODS

We reviewed patients who underwent radical prostatectomy (RP) and developed BCR at three institutions. After excluding patients whose nadir prostate-specific antigen (PSA) was higher than 0.2 ng/mL, those who received neoadjuvant/adjuvant therapy, and those whose BCR was not treated until their PSA exceeded 4.0 ng/mL, the remaining 335 patients comprised the cohort of this study. Salvage RT and ADT were performed for 154 and 181 patients, respectively. After the failure of salvage RT, all patients received subsequent ADT. The starting point of this study was the timing of BCR and the endpoint was the development of castration-resistant prostate cancer (CRPC).

RESULTS

During the mean follow-up period of 8.5 years after BCR, CRPC was observed in 13 patients administered RT and 24 patients administered ADT. Kaplan-Meier curves demonstrated no significant difference in CRPC-free survival between the RT and ADT groups (10-year CRPC-free survival 89.9 vs. 86.3%, p = 0.199). On the other hand, we found a significant difference in CRPC-free survival between the RT and ADT groups in 50 high-risk patients with two risk factors of Grade Group ≥ 4 and PSA-doubling time  < 6 months (10-year CRPC-free survival 73.4 vs. 40.3%, p = 0.040).

CONCLUSION

This study revealed that salvage RT increases the CRPC-free survival rate compared with salvage ADT in high-risk patients with Grade Group ≥ 4 and PSA-doubling time < 6 months.

Landscape of Immunotherapy in Genitourinary Malignancies

The past decade has witnessed a revolution in the development of immune checkpoint inhibitors for the treatment of multiple tumor types, including genitourinary cancers. Immune checkpoint inhibitors have notably improved the treatment outcomes of patients with metastatic renal cell carcinoma and metastatic urothelial carcinoma. In prostate cancer, the role of immunotherapy with checkpoint inhibitors is not yet established except for microsatellite instability high (MSI-H) tumors. Other immunotherapeutic approaches that have been explored in these malignancies include cytokines, vaccines, and cellular therapy. Ongoing studies are exploring the use of immunotherapy combinations as well as combination with chemotherapy and targeted therapy in these types of tumors. The use of immunotherapy beyond the metastatic setting is an active area of research. Moreover, there is great interest in biomarker development to predict response to immunotherapy and risk of toxicity. This book chapter is a comprehensive review of immunotherapeutic approaches, both approved and investigational, for the treatment of renal cell carcinoma, urothelial carcinoma, and prostate cancer.

Cardiovascular Toxicities of Androgen Deprivation Therapy

OPINION STATEMENT

Prostate cancer is the second leading cause of cancer death in men, and cardiovascular disease is the number one cause of death in patients with prostate cancer. Androgen deprivation therapy, the cornerstone of prostate cancer treatment, has been associated with adverse cardiovascular events. Emerging data supports decreased cardiovascular risk of gonadotropin releasing hormone (GnRH) antagonists compared to agonists. Ongoing clinical trials are assessing the relative safety of different modalities of androgen deprivation therapy. Racial disparities in cardiovascular outcomes in prostate cancer patients are starting to be explored. An intriguing inquiry connects androgen deprivation therapy with reduced risk of COVID-19 infection susceptibility and severity. Recognition of the cardiotoxicity of androgen deprivation therapy and aggressive risk factor modification are crucial for optimal patient care.

Liquid chromatography-mass spectrometry applications for quantification of endogenous sex hormones

Liquid chromatography, coupled with tandem mass spectrometry, presents a powerful tool for the quantification of the sex steroid hormones 17-β estradiol, progesterone and testosterone from biological matrices. The importance of accurate quantification with these hormones, even at endogenous levels, has evolved with our understanding of the role these regulators play in human development, fertility and disease risk and manifestation. Routine monitoring of these analytes can be accomplished by immunoassay techniques, which face limitations on specificity and sensitivity, or using gas chromatography-mass spectrometry. LC-MS/MS is growing in capability and acceptance for clinically relevant quantification of sex steroid hormones in biological matrices and is able to overcome many of the limitations of immunoassays. Analyte specificity has improved through the use of novel derivatizing agents, and sensitivity has been refined through the use of high-resolution chromatography and mass spectrometric technology. This review highlights these innovations, among others, in LC-MS/MS steroid hormone analysis captured in the literature over the last decade.

LncRNA AFAP1-AS1 modulates the sensitivity of paclitaxel-resistant prostate cancer cells to paclitaxel via miR-195-5p/FKBP1A axis

LncRNA AFAP1-AS1 has been corroborated to function in diverse cancers. Our aim was to investigate the molecular mechanism of AFAP1-AS1 in PTX resistance in PCa. The levels of AFAP1-AS1, miR-195-5p, and FKBP1A were checked by qRT-PCR. 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-Diphenyltetrazolium Bromide (MTT) assay was employed to assess the resistance of PTX-resistant PCa cells to PTX. Flow cytometry was introduced to evaluate cell apoptosis. The protein levels of C-caspase 3 were determined by western blot. The starBase was used to predict the interaction between miR-195-5p and AFAP1-AS1. Xenograft tumor model was established to investigate the biological role of AFAP1-AS1 in PTX resistance in vivo. The levels of AFAP1-AS1 and FKBP1A were upregulated in PCa tissues and cells, as well as PTX-resistant PCa cells, while the expression of miR-195-5p was declined. Knockdown of AFAP1-AS1 promoted the sensitivity of PTX-resistant PCa cells to PTX, induced apoptosis of PTX-resistant PCa cells, whereas the impacts could be reversed by reducing the expression of miR-195-5p. FKBP1A overexpression could rescue the effects of miR-195-5p-mediated enhancement on the sensitivity of PTX-resistant PCa cells to PTX, promotion on apoptosis of PTX-resistant PCa cells. AFAP1-AS1 interacted with miR-195-5p and miR-195-5p could bind to the 3'UTR of FKBP1A. AFAP1-AS1 silencing inhibited the tumor growth in mice implanted with PC3-TXR cell. The protein level of PCNA was decreased in PC3-TXR cells transfected with sh-AFAP1-AS1, while the expression of C-caspase 3 was upregulated. AFAP1-AS1 silencing attenuated the resistance of PTX-resistant PCa cells to PTX by downregulating FKBP1A via sponging miR-195-5p.

The Potential Role for Immunotherapy in Biochemically Recurrent Prostate Cancer

Biochemically recurrent prostate cancer represents a stage of prostate cancer where conventional (continued on next page) computed tomography and technetium Tc 99m bone scan imaging are unable to detect disease after curative intervention despite rising prostate-specific antigen. There is no clear standard of care and no systemic therapy has been shown to improve survival. Immunotherapy-based treatments potentially are attractive options relative to androgen deprivation therapy due to the generally more favorable side-effect profile. Biochemically recurrent prostate cancer patients have a low tumor burden and likely lymph node-based disease, which may make them more likely to respond to immunotherapy.

Clinical Outcomes of Combined Prostate- and Metastasis-Directed Radiation Therapy for the Treatment of De Novo Oligometastatic Prostate Cancer

PURPOSE

The Systemic Therapy in Advancing or Metastatic Prostate Cancer: Evaluation of Drug Efficacy (STAMPEDE) trial reported overall survival benefits for prostate-directed radiation therapy (PDRT) in low-burden metastatic prostate cancer. Oligometastasis-directed radiation therapy (ORT) improves androgen deprivation therapy (ADT)-free and progression-free survivals. Comprehensive PDRT + ORT to all detectable metastases may offer benefit for de novo oligometastatic prostate cancer (DNOPC) and is under prospective study; given few available benchmarks, we reviewed our institutional experience.

METHODS AND MATERIALS

Forty-seven patients with DNOPC with predominantly M1b disease received neoadjuvant, concurrent, and adjuvant ADT plus PDRT + ORT to 1 to 6 oligometastases. Gross pelvic (N1) nodes were not considered oligometastases unless focally targeted without broader nodal coverage. Outcomes were analyzed from radiation therapy (RT) start using Kaplan-Meier, competing risks, and Cox regression. Median follow-up was 27 (95% confidence interval, 16-42) months.

RESULTS

At 1- and 2-years post-RT, cumulative incidence of distant metastatic progression (DMP) was 21% and 32%, whereas overall survival was 90% and 87%, respectively. Neuroendocrine/intraductal histology, prostate-specific antigen (PSA) < 20, and detectable PSA after PDRT + ORT were associated with increased DMP risk; number and location of oligometastases were not. Local failure was rare, with 3 prostate recurrences and progression of 10 treated oligometastases during follow-up. After neoadjuvant ADT, 9 (19%) patients had undetectable PSA (<0.05 ng/mL), which increased to 32 (68%) after PDRT + ORT. Overall 2-year incidence of biochemical recurrence (BCR) and development of castrate resistance were 23% and 36%, respectively. Undetectable PSA post-RT was associated with lower risk of BCR (hazard ratio, 0.19; P = .004) and DMP (hazard ratio, 0.26; P = .025). Overall, 23 (49%) patients were trialed off ADT; 16 (70%) had testosterone recovery (>150 ng/dL) and, of these, 5 had subsequent PSA rise and restarted ADT 2 to 21 months postrecovery. The remaining 11 were maintained off ADT without BCR. Median noncastrate duration was 8 months; 7 patients had normalized testosterone for >1 year.

CONCLUSIONS

A comprehensive, radiotherapeutic-based treatment strategy has favorable clinical outcomes and can produce prolonged noncastrate remissions in a subset with DNOPC.