Androgen Receptor Pathway-Independent Prostate Cancer Is Sustained through FGF Signaling
Androgen receptor (AR) signaling is a distinctive feature of prostate carcinoma (PC) and represents the major therapeutic target for treating metastatic prostate cancer (mPC). Though highly effective, AR antagonism can produce tumors that bypass a functional requirement for AR, often through neuroendocrine (NE) transdifferentiation. Through the molecular assessment of mPCs over two decades, we find a phenotypic shift has occurred in mPC with the emergence of an AR-null NE-null phenotype. These "double-negative" PCs are notable for elevated FGF and MAPK pathway activity, which can bypass AR dependence. Pharmacological inhibitors of MAPK or FGFR repressed the growth of double-negative PCs in vitro and in vivo. Our results indicate that FGF/MAPK blockade may be particularly efficacious against mPCs with an AR-null phenotype.
Myc regulates a transcriptional program that stimulates mitochondrial glutaminolysis and leads to glutamine addiction
Mammalian cells fuel their growth and proliferation through the catabolism of two main substrates: glucose and glutamine. Most of the remaining metabolites taken up by proliferating cells are not catabolized, but instead are used as building blocks during anabolic macromolecular synthesis. Investigations of phosphoinositol 3-kinase (PI3K) and its downstream effector AKT have confirmed that these oncogenes play a direct role in stimulating glucose uptake and metabolism, rendering the transformed cell addicted to glucose for the maintenance of survival. In contrast, less is known about the regulation of glutamine uptake and metabolism. Here, we report that the transcriptional regulatory properties of the oncogene Myc coordinate the expression of genes necessary for cells to engage in glutamine catabolism that exceeds the cellular requirement for protein and nucleotide biosynthesis. A consequence of this Myc-dependent glutaminolysis is the reprogramming of mitochondrial metabolism to depend on glutamine catabolism to sustain cellular viability and TCA cycle anapleurosis. The ability of Myc-expressing cells to engage in glutaminolysis does not depend on concomitant activation of PI3K or AKT. The stimulation of mitochondrial glutamine metabolism resulted in reduced glucose carbon entering the TCA cycle and a decreased contribution of glucose to the mitochondrial-dependent synthesis of phospholipids. These data suggest that oncogenic levels of Myc induce a transcriptional program that promotes glutaminolysis and triggers cellular addiction to glutamine as a bioenergetic substrate.
Glutamine addiction: a new therapeutic target in cancer
Most cancers depend on a high rate of aerobic glycolysis for their continued growth and survival. Paradoxically, some cancer cell lines also display addiction to glutamine despite the fact that glutamine is a nonessential amino acid that can be synthesized from glucose. The high rate of glutamine uptake exhibited by glutamine-dependent cells does not appear to result solely from its role as a nitrogen donor in nucleotide and amino acid biosynthesis. Instead, glutamine plays a required role in the uptake of essential amino acids and in maintaining activation of TOR (target of rapamycin) kinase. Moreover, in many cancer cells, glutamine is the primary mitochondrial substrate and is required for maintenance of mitochondrial membrane potential and integrity and for support of the NADPH production needed for redox control and macromolecular synthesis.
Technology-enhanced AcceleRation of Germline Evaluation for Therapy (TARGET): A randomized controlled trial of a pretest patient-driven webtool vs. genetic counseling for prostate cancer germline testing
BACKGROUND:Germline testing has an increasingly important role in prostate cancer care. However, a relative shortage of genetic counselors necessitates alternate strategies for delivery of pre-test education for germline testing. This study, funded by the Prostate Cancer Foundation, seeks to address the need for novel methods of delivery of pre-test germline education beyond traditional germline counseling to facilitate informed patient decision-making for germline testing. METHODS:This is a two-armed randomized controlled trial (RCT) with a target enrollment of 173 participants with prostate cancer per study arm (total anticipated nâ€¯=â€¯346). Patients who meet criteria for germline testing based on tumor features, family history or Ashkenazi Jewish ancestry are being recruited from 5 US sites including academic, private practice and Veterans healthcare settings. Consenting participants are randomized to the interactive pretest webtool or germline counseling with assessment of key patient-reported outcomes involved in informed decision-making for germline testing. RESULTS:Participants complete surveys at baseline, after pretest education/counseling, and following disclosure of germline results. The primary outcome of the study is decisional conflict for germline testing. Secondary outcomes include genetic knowledge, satisfaction, uptake of germline testing, and understanding of results. CONCLUSION/CONCLUSIONS:Our hypothesis is that the web-based genetic education tool is non-inferior to traditional genetic counseling regarding key patient-reported outcomes involved in informed decision-making for germline testing. If proven, the results would support deploying the webtool across various practice settings to facilitate pre-test genetic education for individuals with prostate cancer and developing collaborative care strategies with genetic counseling. CLINICALTRIALS/RESULTS:gov Identifier: NCT04447703.
The Impact of Androgen Deprivation Therapy on COVID-19 Illness in Men With Prostate Cancer
BACKGROUND:TMPRSS2, a cell surface protease regulated by androgens and commonly upregulated in prostate cancer (PCa), is a necessary component for SARS-CoV-2 viral entry into respiratory epithelial cells. Previous reports suggested a lower risk of SARS-CoV-2 among PCa patients on androgen deprivation therapy (ADT). However, the impact of ADT on severe COVID-19 illness is poorly understood. METHODS:We performed a multicenter study across 7 US medical centers and evaluated patients with PCa and SARS-CoV-2 detected by polymerase-chain-reaction between March 1, 2020, and May 31, 2020. PCa patients were considered on ADT if they had received appropriate ADT treatment within 6 months of COVID-19 diagnosis. We used multivariable logistic and Cox proportional-hazard regression models for analysis. All statistical tests were 2-sided. RESULTS:We identified 465 PCa patients (median age = 71â€‰years) with a median follow-up of 60â€‰days. Age, body mass index, cardiovascular comorbidity, and PCa clinical disease state adjusted overall survival (hazard ratio [HR] = 1.16, 95% confidence interval [CI] = 0.68 to 1.98, Pâ€‰=â€‰.59), hospitalization status (HR = 0.96, 95% CI = 0.52 to 1.77, Pâ€‰=â€‰.90), supplemental oxygenation (HR 1.14, 95% CI = 0.66 to 1.99, Pâ€‰=â€‰.64), and use of mechanical ventilation (HR = 0.81, 95% CI = 0.25 to 2.66, Pâ€‰=â€‰.73) were similar between ADT and non-ADT cohorts. Similarly, the addition of androgen receptor-directed therapy within 30 days of COVID-19 diagnosis to ADT vs ADT alone did not statistically significantly affect overall survival (androgen receptor-directed therapy: HR = 1.27, 95% CI = 0.69 to 2.32, Pâ€‰=â€‰.44). CONCLUSIONS:In this retrospective cohort of PCa patients, the use of ADT was not demonstrated to influence severe COVID-19 outcomes, as defined by hospitalization, supplemental oxygen use, or death. Age 70â€‰years and older was statistically significantly associated with a higher risk of developing severe COVID-19 disease.
Germline APC (I1307K) mutation and clinical outcomes in prostate cancer [Meeting Abstract]
Background: The germline I1307K mutation in the adenomatous polyposis coli (APC) gene is a well known alteration identified in approximately 6% of the Ashkenazi Jewish population. Individuals with this mutation have an increased risk of developing colorectal and other cancers. The implications of the APC (I1307K) mutation in patients with prostate cancer are unknown. We sought to determine the clinical outcomes of patients with prostate cancer and the germline APC (I1307K) mutation.
Method(s): We retrospectively reviewed records from New York University and Johns Hopkins University to identify patients with the APC (I1307K) mutation. Eligibility criteria included the identification of the mutation either on germline or somatic tissue testing (when germline testing was not available). Aggressive variant prostate cancer (AVPC) was defined using previously established criteria including: presence of small cell histology, presence of exclusively visceral metastases, bulky prostate mass or lymphadenopathy, low PSA with high-volume ( > 20) bone metastases, neuroendocrine marker positivity or short interval ( < 6 months) to castration resistance. Combined somatic alterations in two or more of following genes were assessed: RB1, TP53, PTEN. These somatic alterations have been previously associated with AVPC. Descriptive statistics were used to summarize patient data.
Result(s): From 2016-2021, 13 patients with the germline APC (I1307K) mutation were identified. At the time of analysis 9 (69%) patients were alive. Most patients (7; 54%) had metastatic disease at presentation. Median PSA at diagnosis was 0.4 ng/mL (range: 0.4-20 ng/mL). The median time to castration resistance among those receiving hormonal therapy was 9 months (range: 3-13 months). Presence of small cell histology was found on initial biopsy in 3 patients and on subsequent biopsy in 1 additional patient (31% overall). Bulky prostate mass or lymphadenopathy was found in 3 (23%) patients. There were 2 (15%) patients who had low PSA with high-volume bone metastases. Four (31%) patients had radiographic progression with no concordant PSA increase. Clinically-defined AVPC was found in 7 (54%) patients and in 100% of those patients with metastatic disease. Combined somatic alterations in two or more of RB1, TP53 or PTEN were identified in 3 (23%) patients.
Conclusion(s): Prostate cancers that develop in the presence of the germline APC (I1307K) mutation appear to be enriched for clinically-defined and molecularly-defined AVPC. Several of these patients demonstrated small cell histology and PSA-independent progression, higher than the expected background rate. This raises the hypothesis that the germline APC (I1307K) mutation influences the somatic genomic and/or epigenomic landscape of prostate cancer. Larger studies to validate the increased risk of AVPC in APC (I1307K) carriers, and to elucidate the somatic alteration landscape in these patients, are ongoing
History of cancer is associated with increased platelet activity and atherothrombosis in patients with peripheral arterydisease [Meeting Abstract]
Background : Cancer and peripheral artery disease (PAD) share common risk factors and are frequently coprevalent. Platelets are culprits in the pathogenesis of PAD and mediators of arterial cardiovascular events. The association between platelet activity and cardiovascular events in patients with versus without cancer is uncertain. Aims : To investigate if cancer history is associated with platelet activity and incident cardiovascular events in a cohort of patients with PAD. Methods : 289 patients with PAD undergoing lower extremity revascularization enrolled in the Platelet Activity and Cardiovascular Events (PACE) study were followed longitudinally for a median of 18 months. Prior to revascularization, patients had platelet activity measured via light transmission aggregometry in response to ADP, collagen, epinephrine, and serotonin. The primary clinical outcome was myocardial infarction (MI). Other endpoints were MI/stroke and major adverse cardiovascular event (MACE; MI/stroke/death). Results : 64 patients (22.1%) reported a cancer history, 10 (15.6%) with metastatic and 10 (15.6%) with active cancer. Patients with (versus without) cancer history were older, less often Hispanic, and less frequently current smokers ( P < 0.05 for each). There was no difference in prevalent diabetes, coronary artery disease, hypertension, or antiplatelet therapy between groups. Platelet aggregation in response to submaximal ADP (0.4 muM, 1.0 muM), collagen (0.2 mug/ml, 1.0 ug/ml), and serotonin (10 muM) was higher in patients with versus without cancer history. Consistently, patients with cancer history experienced more incident MI (18.8% vs. 7.6%, P = 0.02), MI/stroke (25.0% vs. 9.3%, P = 0.002), and MACE (35.9% vs. 22.2%, P = 0.04). After adjustment for age, sex, race/ethnicity, smoking, diabetes, prior stroke, CAD, revascularization procedure, and antiplatelet therapy, patients with cancer history were at higher hazard for MI, MI/stroke, and MACE (Figure). The association between cancer and thrombotic events was most apparent in patients with metastatic and active cancer (Figure). Conclusions : In patients with PAD, cancer history was associated with increased platelet aggregation and risk for arterial thrombotic events
The role of androgen deprivation therapy on the clinical course of COVID-19 infection in men with prostate cancer [Meeting Abstract]
Background: TMPRSS2, a cell surface protease which is commonly upregulated in prostate cancer (PC) and regulated by androgens, is a necessary component for SARS-CoV2 cellular entry into respiratory epithelial cells. PC patients receiving ADT were reported to have a lower risk of SARSCoV- 2 infection. However, whether ADT may have an impact on the severity of COVID-19 illness in this population is poorly understood.
Method(s): In this study performed across 7 US medical centers, we retrospectively evaluated patients with active PC and SARS-COV-2 viral detection by PCR between 03/01/20 and 05/31/20. We collected information on demographics; medical comorbidities; medications; PC Gleason score at initial diagnosis; presence of active disease, metastases, and castration resistance; ADT use as defined by GnRH analog or antagonist within 3 months or castration levels of testosterone < 50 ng/dL within 6 months of COVID-19 diagnosis, or history of bilateral orchiectomy; active non-ADT systemic therapies including, but not limited to, androgen-receptor-targeted therapies and chemotherapy; and COVID-19-related outcomes including hospitalization, supplemental oxygen use, mechanical ventilation requirement, WHO COVID-19 ordinal scale for clinical improvement, follow-up duration, and vital status. Multivariable mixed-effect logistic regression was performed to evaluate any difference in COVID-19 clinical outcomes between patients on and not on ADT. Survival analysis was done using adjusted Cox proportion-hazards regression model. All tests were two-sided at 0.05 significance level.
Result(s): We identified 465 evaluable patients with median age of 71 (61-81) years. Median duration of follow-up was 60 (12-114.2) days. In this follow up period, there were 195 (41.9%) hospitalizations and 111 (23.9%) deaths. When adjusted for age, BMI, and PC clinical disease state, overall survival (HR 1.28 [95%CI 0.79-2.08], P = 0.32), hospitalization status (HR 1.07 [0.61-1.87], P = 0.82), supplemental oxygen use (HR 1.29 [0.77-2.17], P = 0.34), and use of mechanical ventilation (HR 1.07 [0.51-2.23], P = 0.87) were not statistically different between ADT and non-ADT cohorts. Similarly, in subgroup analysis, no statistical difference in overall survival was found between ADT and non-ADT cohorts for hospitalized patients (HR 1.42 [0.82-2.47], P = 0.21) and those receiving supplemental oxygen (HR 1.10 [0.65-1.85], P = 0.73).
Conclusion(s): In this retrospective cohort of PC patients, use of ADT prior to COVID-19 diagnosis does not protect against severe COVID-19 illness as defined by hospitalization, supplemental oxygen use, or death. Further preclinical work in understanding TMPRSS2 expression and androgen regulation in respiratory epithelial cells is needed. As well, longer clinical follow-up and additional clinical studies inclusive of prospective data are warranted to fully address this question
Knowledge and practice regarding prostate cancer germline testing among urologists: Gaps to address for optimal implementationâœ°,âœ°âœ°
BACKGROUND:Germline testing is recommended for all men with metastatic prostate cancer (PCa), and for some with localized PCa meeting specific histologic or family history criteria. Germline genetic evaluation has important implications for PCa prognosis and management, as well as implications for family members and cancer screening. Despite the importance of germline evaluation, its utilization in urologic practice is unknown. MATERIALS AND METHODS/METHODS:We conducted a 32-item survey of U.S. urologists to examine knowledge of germline testing guidelines and practice patterns. It was shared through email to 6 American Urological Association sections, the Veterans Affairs Urology Mailgroup, and social media. RESULTS:Among 132 total respondents from diverse practice settings across the U.S., 12% perform germline testing, 44% refer to a genetic counselor, 11% do both, and 33% do not test/refer. Only 4% had formal education in genetics. While 98% ask about PCa family history, only 76% and 52% ask about breast and ovarian cancer. When presented with hypothetical case scenarios where germline testing is indicated, many respondents indicated they would not offer genetic counseling or testing. Younger age (pÂ =Â 0,03), academic practice (pÂ =Â 0.04), and specializing in PCa/oncology (pÂ =Â 0.007) were significantly associated with performing or referring for germline testing. Specializing in PCa/oncology was significantly associated with recommending germline testing for all case scenarios involving metastatic PCa (pÂ =Â 0.0009) CONCLUSION: Our results suggest significant gaps in knowledge of germline testing and alignment of practice with national guidelines among urologists. Germline testing education and facilitation of genetic evaluation in urologic practice is warranted.
A phase Ib/II, open-label, randomized platform study evaluating the efficacy and safety of AB928-based treatment combinations in patients with metastatic castrate resistant prostate cancer [Meeting Abstract]
Background: Standard of care (SOC) regimens may contribute to immunosuppression by elevating intratumoral levels of adenosine, which activates the A2a and A2b receptors (R) on immune cells. Extracellular adenosine is primarily produced by the enzyme CD73. In prostate cancer, the activity of the highly expressed protein, prostatic acid phosphatase, produces additional adenosine. AB928, which is the first clinical-stage small molecule dual antagonist of both A2aR and A2bR, is highly potent, pharmacodynamically active, and well tolerated in dose escalation studies in combination with chemo/immunotherapy. Targeting the adenosine axis in combination with SOC regimens or immunotherapy may have a more profound effect on activating and inducing sustained antitumor immunity in patients (pts) with metastatic castrate-resistant prostate cancer (mCRPC). Trial design: This is a phase (Ph) 1b/2, open-label, multicenter platform trial to evaluate the antitumor activity and safety of AB928-based combination therapy in pts with mCRPC. Eligibility for a specific treatment arm will be informed by prior anticancer therapy. Treatment arms will independently evaluate AB928 + zimberelimab (AB122; anti-PD-1 antibody) alone or in combination with an SOC backbone (enzalutamide or docetaxel) in earlier-line pts or AB928 + AB680 (CD73 inhibitor) +/- zimberelimab in later-line pts. Treatment arms will be conducted in 2 stages: Stage 1 (Ph1b) and Stage 2 (Ph2). In Ph1b, up to 15 pts will receive investigational product(s) at the single agent recommended dose with SOC per label guidance. Provided safety and futility stopping criteria are not met, further accrual in the earlier-line arms will involve randomization to SOC alone; in the later-line arms, upfront randomization to the all-experimental regimens will continue in Ph2. Investigator-assessed antitumor response (radiologic, prostate specific antigen [PSA]) will follow PCWG3 criteria. New treatment arms may be added via protocol amendment. ARC-6 is actively recruiting in the United States, and results will be shared in upcoming scientific conferences (NCT04381832). Clinical trial identification: NCT04381832. Legal entity responsible for the study: Arcus Biosciences.
Funding(s): Arcus Biosciences. Disclosure: S.K. Subudhi: Advisory/Consultancy, Research grant/Funding (self): Janssen Oncology; Advisory/Consultancy: Polaris; Advisory/Consultancy: Dendreon; Advisory/Consultancy, Shareholder/Stockholder/Stock options: Apricity Health; Advisory/Consultancy: Amgen; Advisory/Consultancy: Bayer; Advisory/Consultancy: Exelixis; Advisory/Consultancy, Research grant/Funding (self): AstraZeneca; Advisory/Consultancy: Bristol-Myers Squibb; Advisory/Consultancy: Dava Oncology; Advisory/Consultancy: Cancer Now; Advisory/Consultancy: MEDACorp; Honoraria (self): Parker Institute of Cancer Immunotherapy; Honoraria (self): SITC. D. Wise: Advisory/Consultancy: ScientiaCME; Advisory/Consultancy: OncLIve; Advisory/Consultancy: Foundation Medicine; Honoraria (self), Advisory/Consultancy: Best Doctors; Advisory/Consultancy: Leap Therapeutics; Advisory/Consultancy: Guidepoint Consulting; Advisory/Consultancy: GLG Consulting; Advisory/Consultancy: Silverlight; Advisory/Consultancy: Alphasights; Advisory/Consultancy: Pfizer. S.T. Liu: Advisory/Consultancy: Merck; Advisory/Consultancy: Exelixis; Advisory/Consultancy: Esai; Advisory/Consultancy: Seattle Genetics. A. Chaudhry: Speaker Bureau/Expert testimony, Research grant/Funding (institution): Bayer; Advisory/Consultancy, Research grant/Funding (institution): Exelixis; Advisory/Consultancy: Astellas Pharma; Shareholder/Stockholder/Stock options: Novartis; Research grant/Funding (institution): Arcus Biosciences; Research grant/Funding (institution): Merck; Research grant/Funding (institution): Abbvie; Research grant/Funding (institution): AstraZeneca; Research grant/Funding (institution): BMS; Research grant/Funding (institution): Eli Lilly; Research grant/Funding (institution): Pfizer; Research grant/Funding (institution): Beigene; Research grant/Funding (institution): BerGenBio; Research grant/Funding (institution): Blueprint; Research grant/Funding (institution): Alkermes; Research grant/Funding (institution): Genentech; Research grant/Funding (institution): Gilead; Research grant/Funding (institution): Janssen; Research grant/Funding (institution): Millennium; Research grant/Funding (institution): Basilea; Research grant/Funding (institution): IunoCare; Research grant/Funding (institution): Amgen; Research grant/Funding (institution): Novartis. J. Kim: Advisory/Consultancy: Sanofi; Advisory/Consultancy: EMD Serono; Advisory/Consultancy: Voluntis; Research grant/Funding (self): Immune Design. O. Gardner: Shareholder/Stockholder/Stock options, Full/Part-time employment: Arcus Biosciences; Shareholder/Stockholder/Stock options, Full/Part-time employment: Bellicum Pharmaceuticals; Full/Part-time employment: Aduro Biotech; Shareholder/Stockholder/Stock options, Full/Part-time employment: Janssen. H. Gilbert: Shareholder/Stockholder/Stock options, Full/Part-time employment: Arcus Biosciences; Advisory/Consultancy, Full/Part-time employment: Bellicum; Shareholder/Stockholder/Stock options, Full/Part-time employment: Roche/Genentech; Shareholder/Stockholder/Stock options: Denali; Shareholder/Stockholder/Stock options: Celgene; Shareholder/Stockholder/Stock options: BMS. M. Grady: Shareholder/Stockholder/Stock options, Full/Part-time employment: Arcus Biosciences; Full/Part-time employment: Bellicum; Full/Part-time employment: Biothera. M. Paoloni: Leadership role, Shareholder/Stockholder/Stock options, Full/Part-time employment: Arcus Biosciences; Advisory/Consultancy: Eli Lilly; Advisory/Consultancy: Janssen Oncology; Advisory/Consultancy: Amgen. K. Krishnan: Leadership role, Shareholder/Stockholder/Stock options, Full/Part-time employment: Arcus Biosciences; Full/Part-time employment: Astex; Full/Part-time employment: Roche/Genentech; Full/Part-time employment: Five Prime. M. Carducci: Advisory/Consultancy, Research grant/Funding (institution): Pfizer; Advisory/Consultancy: Medivation; Advisory/Consultancy: Astellas; Advisory/Consultancy: Roche; Advisory/Consultancy: Abbvie; Advisory/Consultancy: Foundation Medicine; Advisory/Consultancy: Merck; Research grant/Funding (institution): EMD Serono; Research grant/Funding (institution): Exelixis; Research grant/Funding (institution): Gilead; Research grant/Funding (institution): Effector; Non-remunerated activity/ies: ECOG-ACRIN.