Aggressive Prostate Cancer Research Articles

Lymphovascular Invasion at the Time of Radical Prostatectomy Adversely Impacts Oncological Outcomes.

Lymphovascular invasion, whereby tumour cells or cell clusters are identified in the lumen of lymphatic or blood vessels, is thought to be an essential step in disease dissemination. It has been established as an independent negative prognostic indicator in a range of cancers. We therefore aimed to assess the impact of lymphovascular invasion at the time of prostatectomy on oncological outcomes. We performed a multicentre, retrospective cohort study of 3495 men who underwent radical prostatectomy for localised prostate cancer. Only men with negative preoperative staging were included. We assessed the relationship between lymphovascular invasion and adverse pathological features using multivariable logistic regression models. Kaplan-Meier curves and Cox proportional hazard models were created to evaluate the impact of lymphovascular invasion on oncological outcomes. Lymphovascular invasion was identified in 19% (n = 653) of men undergoing prostatectomy. There was an increased incidence of lymphovascular invasion-positive disease in men with high International Society of Urological Pathology (ISUP) grade and non-organ-confined disease (p < 0.01). The presence of lymphovascular invasion significantly increased the likelihood of pathological node-positive disease on multivariable logistic regression analysis (OR 15, 95%CI 9.7-23.6). The presence of lymphovascular invasion at radical prostatectomy significantly increased the risk of biochemical recurrence (HR 2.0, 95%CI 1.6-2.4). Furthermore, lymphovascular invasion significantly increased the risk of metastasis in the whole cohort (HR 2.2, 95%CI 1.6-3.0). The same relationship was seen across D'Amico risk groups. The presence of lymphovascular invasion at the time of radical prostatectomy is associated with aggressive prostate cancer disease features and is an indicator of poor oncological prognosis.

Development and Optimization of a Subtraction-Normalized Immunocyte Profiling Signature for Prostate Cancer Active Surveillance Risk Stratification.

Less invasive decision support tools are desperately needed to identify occult high-risk disease in men with prostate cancer (PCa) on active surveillance (AS). For a variety of reasons, many men on AS with low- or intermediate-risk disease forgo the necessary repeat surveillance biopsies needed to identify potentially higher-risk PCa. Here, we describe the development of a blood-based immunocyte transcriptomic signature to identify men harboring occult aggressive PCa. We then validate it on a biopsy-positive population with the goal of identifying men who should not be on AS and confirm those men with indolent disease who can safely remain on AS. This model uses subtraction-normalized immunocyte transcriptomic profiles to risk-stratify men with PCa who could be candidates for AS. Men were eligible for enrollment in the study if they were determined by their physician to have a risk profile that warranted prostate biopsy. Both training (n = 1017) and validation cohort (n = 1198) populations had blood samples drawn coincident to their prostate biopsy. Purified CD2+ and CD14+ immune cells were obtained from peripheral blood mononuclear cells, and RNA was extracted and sequenced. To avoid overfitting and unnecessary complexity, a regularized regression model was built on the training cohort to predict PCa aggressiveness based on the National Comprehensive Cancer Network PCa guidelines. This model was then validated on an independent cohort of biopsy-positive men only, using National Comprehensive Cancer Network unfavorable intermediate risk and worse as an aggressiveness outcome, identifying patients who were not appropriate for AS. The best final model for the AS setting was obtained by combining an immunocyte transcriptomic profile based on 2 cell types with PSA density and age, reaching an AUC of 0.73 (95% CI: 0.69-0.77). The model significantly outperforms (P < .001) PSA density as a biomarker, which has an AUC of 0.69 (95% CI: 0.65-0.73). This model yields an individualized patient risk score with 90% negative predictive value and 50% positive predictive value. While further validation in an intended-use cohort is needed, the immunocyte transcriptomic model offers a promising tool for risk stratification of individual patients who are being considered for AS.

Anti-Müllerian hormone: a novel biomarker for aggressive prostate cancer? Emerging evidence from a prospective study of radical prostatectomies.

Prostate cancer patients are a heterogeneous group as regards the aggressiveness of the disease. The relationship of steroid hormones with the aggressiveness of prostate cancer is unclear. It is known that the anti-Müllerian hormone (AMH) inhibits prostate cancer cell lines in vitro. The aim of this study is to investigate the relationship of AMH and steroid hormones with the aggressiveness of prostate cancer. This was a prospective study of consecutive radical prostatectomy patients. We measured the following hormones: total testosterone, sex hormone-binding globulin, albumin, luteinizing hormone, follicle-stimulating hormone, estradiol, dehydroepiandrosterone sulfate, androstenedione, and AMH. The minimum follow-up after radical prostatectomy was 5years. For the aggressiveness of prostate cancer, we considered the following three variables: post-operative Gleason score (GS) ≥ 8, TNM pΤ3 disease, and prostate-specific antigen (PSA) biochemical recurrence (BCR). In total, 91 patients were enrolled. The mean age and PSA were 64.8years and 9.3ng/dl, respectively. The median post-operative GS was 7. Low AMH blood levels were correlated with higher post-operative GS (p = 0.001), as well as with PSA BCR (p = 0.043). With pT3 disease, only albumin was (negatively) correlated (p = 0.008). ROC analysis showed that AMH is a good predictor of BCR (AUC 0.646, 95% CI 0.510-0.782, p = 0.043); a cutoff value of 3.06ng/dl had a positive prognostic value of 71.4% and a negative prognostic value of 63.3% for BCR. Cox regression analysis showed that AMH is a statistically significant and independent prognostic marker for BCR (p = 0.013). More precisely, for every 1ng/ml of AMH rise, the probability for PSA BCR decreases by 20.8% (HR = 0.792). Moreover, in Kaplan-Meier analysis, disease-free survival is more probable in patients with AMΗ ≥ 3.06ng/ml (p = 0.004). Low AMH blood levels were correlated with aggressive prostate cancer in this radical prostatectomy cohort of patients. Therefore, AMH could be a prognostic biomarker for the aggressiveness of the disease.

Receptor tyrosine kinase-like orphan receptor 1 inhibitor strictinin exhibits anti-cancer properties against highly aggressive androgen-independent prostate cancer

Aim: It is important to identify anti-cancer compounds that can inhibit specific molecular targets to eradicate androgen-receptor negative (ARneg), androgen-independent (AI) prostate cancer, which is an aggressive form of prostate cancer with limited treatment options. The goal of this study was to selectively target prostate cancer cells that have high levels of oncogenic protein Receptor tyrosine kinase-like orphan receptor 1 (ROR1) by using strictinin, a small molecule ROR1 inhibitor. Methods: The methods performed in this study include western blots, methyl thiazolyl tetrazolium (MTT) proliferation assays, phosphatidylserine apoptosis assays, apoptosis flow cytometry (Annexin V, caspase 3/7), migration scratch assays, Boyden chamber invasion assays, and cell cycle flow cytometry. Results: Strictinin was most lethal against PC3 [half-maximal drug inhibitory concentration (IC50) of 277.2 µmol/L], an ARneg-AI cell type that expresses the highest levels of ROR1. Strictinin inhibited ROR1 expression, downstream phosphatidylinositol 3-kinase (PI3K)-protein kinase B (AKT)-glycogen synthase kinase 3beta (GSK3β) pro-survival signaling, and epithelial-to-mesenchymal transition markers in PC3 cells. Additionally, strictinin decreased PC3 cell migration and invasion, while increasing S-phase cell cycle arrest. In ARneg-AI DU145 cells, strictinin inhibited ROR1 expression and modulated downstream AKT-GSK3β signaling. Furthermore, strictinin exhibited anti-migratory, anti-invasive, but minimal pro-apoptotic effects in DU145 cells likely due to DU145 having less ROR1 expression in comparison to PC3 cells. Throughout the study, strictinin minimally impacted the phenotype of normal prostatic epithelial cells RWPE-1 (IC50 of 658.5 µmol/L). Strictinin was further identified as synergistic with docetaxel [combination index (CI) = 0.311] and the combination therapy was found to reduce the IC50 of strictinin to 38.71 µmol/L in PC3 cells. Conclusions: ROR1 is an emerging molecular target that can be utilized for treating prostate cancer. The data from this study establishes strictinin as a potential therapeutic agent that targets ARneg-AI prostate cancer with elevated ROR1 expression to reduce the migration, invasion, cell cycle progression, and survival of prostate cancer.

Variable effects of periprostatic adipose tissue on prostate cancer cells: Role of adipose tissue lipid composition and cancer cells related factors.

Periprostatic adipose tissue (PPAT) is likely to modulate prostate cancer (PCa) progression. We analyzed the variations in the effect of PPAT on cancer cells, according to its fatty acid (FA) composition and tumor characteristics. The expression of markers of aggressiveness Ki67 and Zeb1, and epigenetic marks that could be modified during PCa progression, was analyzed by immunohistochemistry on a tissue-micro-array containing 59 pT3 PCa, including intra-prostatic areas and extra-prostatic foci in contact with PPAT belonging to the same tumor. In addition, we cocultivated PC3 and LNCaP cell lines with PPAT, which were then analyzed for FA composition. Although the contact between PPAT and cancer cells led overall to an increase in Ki67 and Zeb1, and a decrease in the epigenetic marks 5MC, 5HMC, and H3K27ac, these effects were highly heterogeneous. Increased proliferation in extra-prostatic areas was associated with the international society of uropathology score. PC3 and LNCaP cocultures with PPAT led to increased Ki67, Zeb1 and H3K27me3, but only for PPAT associated with aggressive PCa. PC3 proliferation was correlated with high 20.2 n-6 and low 20.5n-3 in PPAT. These results suggest that the effects of PPAT on cancer cells may depend on both PCa characteristics and PPAT composition, and could lead to propose nutritional supplementation.

Letter to the editor: Aggressive variant prostate cancer: An exemplary case study and comprehensive literature survey.

This article enthusiastically explores the study of highly aggressive variant prostate cancer (AVPC), acknowledging its relatively rare yet highly menacing presence within the realm of prostate cancer. The paper delves into the pathological characteristics of AVPC, diagnostic and therapeutic challenges, and the potential applications of precision medicine and molecular imaging in the future.

Apparent Diffusion Coefficient of Variation (ADC&lt;sub&gt;cv&lt;/sub&gt;): A New Biomarker for Aggressiveness in Prostate Cancer?

Apparent Diffusion Coefficient of Variation (ADC&lt;sub&gt;cv&lt;/sub&gt;): A New Biomarker for Aggressiveness in Prostate Cancer?

Active DHEA uptake in the prostate gland correlates with aggressive prostate cancer.

Strategies for patient stratification and early intervention are required to improve clinical benefits for patients with prostate cancer. Here, we found that active DHEA utilization in the prostate gland correlated with tumor aggressiveness at early disease stages, and 3βHSD1 inhibitors were promising for early intervention. [3H]-labeled DHEA consumption was traced in fresh prostatic biopsies ex vivo. Active DHEA utilization was more frequently found in patients with metastatic disease or therapy-resistant disease. Genetic and transcriptomic features associated with the potency of prostatic DHEA utilization were analyzed to generate clinically accessible approaches for patient stratification. UBE3D, by regulating 3βHSD1 homeostasis, was discovered to be a regulator of patient metabolic heterogeneity. Equilin suppressed DHEA utilization and inhibited tumor growth as a potent 3βHSD1 antagonist, providing a promising strategy for the early treatment of aggressive prostate cancer. Overall, our findings indicate that patients with active prostatic DHEA utilization might benefit from 3βHSD1 inhibitors as early intervention.

Biological and clinical significance of the AGE-RAGE axis in the aggressiveness and prognosis of prostate cancer.

Dietary factors and chronic hyperglycemia are linked to the formation of advanced glycation end products (AGEs) and prostate cancer (PCa) risk. The activation of the receptor for AGEs (RAGE) acts as a bridge between various RAGE ligands and certain malignancies. This study showed that the interaction of AGEs and RAGE promoted PCa cell proliferation, invasion, and autophagy-mediated survival in response to chemotherapeutic agents. RAGE-overexpressed PCa cells underwent epithelial-mesenchymal transition and showed increased cancer stem cell-like properties. In mouse xenograft models, RAGE-overexpressed cells showed more substantial tumorigenic capacity than parental cells, whereas RAGE knockdown decreased tumorigenicity. The clinical data validated a positive correlation between high AGE and RAGE expressions with poor clinical outcomes. Our findings suggest that the AGE-RAGE axis facilitates PCa progression and aggressiveness. Prostatic AGEs and RAGE expression levels are associated with PCa prognosis. Adherence to a reduced-AGE diet and targeting RAGE are potential approaches to complement and synergize with the current PCa therapies.

Improving Predictive Ability of Prostate Cancer Aggressiveness Using Multi-Modal Radiomic Features and Feature-Level Correlations in Multi-parametric MRI

Improving Predictive Ability of Prostate Cancer Aggressiveness Using Multi-Modal Radiomic Features and Feature-Level Correlations in Multi-parametric MRI

Abstract B096: Cigarette smoking and prostate cancer aggressiveness among African and European American men

Abstract Background: Smoking is a modifiable lifestyle factor linked to prostate cancer (PCa) risk, but its association with PCa aggressiveness is unclear. Further, African-American men are likelier to smoke and be at risk for PCa. Therefore, we examined racial disparities in the association between cigarette smoking and PCa aggressiveness. Methods: Data for this study came from the North Carolina-Louisiana Prostate Cancer Project, a registry-based cohort study of incident PCa cases from 2004-2009 (n = 1,457). We defined PCa aggressiveness as high (Gleason score ≥ 8, Gleason score = 7 and TNM T3-T4, or prostate-specific antigen (PSA) score &amp;gt; 20 ng/mL) or low (Gleason score &amp;lt; 7, TNM T1-T2, and PSA &amp;lt; 10 ng/mL). We classified cigarette smoking as current, former, or never. Our analyses used multivariable logistic regression to estimate adjusted odds ratios (OR) and 95% confidence intervals (CI). Results: One-third (35%) of PCa cases were high-aggressive. Half (48%) of the study sample was African-American. Current smoking, but not former smoking, was associated with high-aggressive PCa compared to never (OR = 2.2; 95% CI [1.5, 3.3]). African-Americans who currently smoked had higher odds of high-aggressive PCa than those who never smoked (OR = 3.2; 95% CI [1.9, 5.4]), as did those who formerly smoked (OR = 1.8; 95% CI [1.2, 2.3]). However, smoking did not significantly predict PCa aggressiveness in European-Americans. Conclusion: Cigarette smoking is associated with PCa aggressiveness, an association moderated by race. Future research should investigate the biological and social effects of smoking and PCa aggressiveness between racial groups. Citation Format: Edgar T. Ellis, Brian J. Fairman, Shelbie D. Stahr, L. Joseph Su, Ping-Ching Hsu. Cigarette smoking and prostate cancer aggressiveness among African and European American men [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr B096.

Abstract C087: Association of serum lipid profile with prostate cancer risk and aggressiveness in Nigerian men

Abstract OBJECTIVE Though prostate cancer (PCa) is the most common cancer and cause of cancer death among Nigerian men, its relationship with serum lipid profiles, a biochemical measurement of dietary fat, has not been explored among Nigerian men. The study aimed to determine the association of serum lipid profile with prostate cancer risk and aggressiveness. METHODS The study was a case-control conducted at University College Hospital, Ibadan, Nigeria. The cases were newly diagnosed prostate cancer patients ages 50-75 years, while the controls were age-matched healthy men with confirmed normal PSA. Participants with uncontrolled comorbidities, poor performance status (ECOG ≥3), and weight loss in the past month were not eligible. The patient characteristics (age, marital status, employment status, highest level of education, high-fat diet, lack of exercise, tobacco smoking, alcohol intake, family history of prostate cancer, comorbidities, and tumor characteristics [PSA at presentation, histology, Gleason score, and stage at presentation] in the cases alone) were collected using an interviewer-administered questionnaire. A serum lipid profile test (including total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) was done in all participants. Analysis of the variables was on SPSS version 23.0, with a t-test to compare the serum lipid profile between the case and control groups, a chi-square to compare the sociodemographic and patient characteristics between both groups and an ANOVA test to determine the association between serum lipid profile and Gleason's score (disease grade) or stage of prostate cancer. RESULTS Enrolled in each group were seventy-four participants. The mean age ± standard deviation was 65.0 ± 5.9 years for cases and 63.0 ± 6.5 years for controls. Participants with a high-fat diet (p = 0.006), physical inactivity (p = 0.046), alcohol consumption (p = 0.005), and family history (p = 0.002) were significantly higher in the case group than the controls. A high proportion of the cases had high-grade disease (GS ≥ 8) [39.2%] and stage 4 disease (35.2%). The mean levels of TC (p&amp;lt;0.001) and HDL-C (p&amp;lt;0.001) were significantly higher in the cases. The mean TG increased while HDL-C decreased as the disease stage advanced but with no statistical significance. While the mean TC (p = 0.001) increased significantly with worsening prostate cancer grade, the mean HDL-C was highest in low-grade disease (p &amp;lt;0.001). CONCLUSION Elevated total cholesterol and high-density lipoprotein cholesterol were associated with increased prostate cancer risk. While elevated total cholesterol was associated with high-grade prostate cancer, a high level of high-density lipoprotein cholesterol was associated with the low-grade disease. Hence, regular serum lipid profile tests may be encouraged among Nigerian men for early detection and treatment of any cholesterol derangement to avoid its predisposition to prostate cancer. Citation Format: Kehinde Oluwatosin Adeyinka, Adeniyi Adenipekun, Atara Ntekim, Augustine Oghenewveyin Takure, Rotimi Solomon. Association of serum lipid profile with prostate cancer risk and aggressiveness in Nigerian men [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr C087.

Abstract PR007: Neighborhood socioeconomic deprivation, racial segregation, and prostate tumor RNA expression of stress-related genes among African American and European American men

Abstract INTRODUCTION: African American (AA) men experience greater prostate cancer incidence and mortality compared to European American (EA) men. Growing literature supports associations of neighborhood social factors (NSF) including neighborhood socioeconomic deprivation and residential segregation with advanced or aggressive prostate cancer, and AA men may experience these factors to a greater extent than EA men. Here we tested associations of NSF with prostate tumor RNA expression of stress-related genes, hypothesizing that these factors would be related and contribute to prostate tumor aggressiveness. METHODS: We leveraged available transcriptomic data from prostate tumor tissue for AA and EA men with prostate cancer who received radical prostatectomy surgery at the University of Maryland Medical Center. We geocoded each participant’s address at diagnosis, determined the corresponding census tract, and assigned tract-based Area Deprivation Index (ADI) and Racial Isolation Index (RI) scores to each participant. Based on data availability, ADI analyses included men diagnosed in 2005 or later (118 AA men and 43 EA men), and RI analyses included those diagnosed in 2009 or later (110 AA men and 37 EA men). We evaluated 105 stress-related genes, including those in the Conserved Transcriptional Response to Adversity, among others. We fit separate linear regression models for expression of each gene in relation to ADI or RI, respectively. Models were adjusted for race and age and year at surgery. We obtained q-values (p-values adjusted for multiple comparisons) using the Benjamini-Hochberg method. RESULTS: Median (interquartile range) ADI scores were 116 (101-131) for AA men and 91 (83-103) for EA men, and RI scores were 0.68 (0.38-0.87) for AA men and 0.10 (0.05-0.14) for EA men, indicating greater neighborhood deprivation and Black residential segregation among AA participants. The greatest values for these scores were concentrated in central and west Baltimore. ADI scores were positively and significantly (p&amp;lt;0.05) associated with expression for 11 genes. One gene, HTR6 (serotonin pathway), remained significant after multiple comparison adjustment (beta=0.0029, 95% confidence interval: 0.0014-0.0043; p&amp;lt;0.001; q=0.02). RI scores were positively and significantly associated with expression for 7 genes (p&amp;lt;0.05), but findings did not remain significant after multiple comparison adjustment. Four genes, including HTR6, IFIT2 and MX2 (roles in Type I IFN response), and IGLL1 (antibody synthesis) were significantly associated with both ADI and RI (p&amp;lt;0.05). Top findings among AA men only were similar to the overall results (AA and EA men combined). CONCLUSIONS: We identified several genes in stress-related pathways whose expression in prostate tumor tissue was higher among men with higher neighborhood deprivation or higher racial segregation. Additional analyses will consider other neighborhood measures, including historical redlining, to further investigate the role of NSF in prostate tumor RNA expression, tumor aggressiveness, and prostate cancer disparities. Citation Format: Joseph Boyle, Jessica Yau, Jimmie L. Slade, Derrick Butts, Yuji Zhang, Teklu B. Legesse, Ashley Cellini, Kimberly Clark, Jessica Wimbush, Nicholas Ambulos Jr., Jing Yin, Arif Hussain, Eberechukwu Onukwugha, Cheryl L. Knott, David C. Wheeler, Kathryn Hughes Barry. Neighborhood socioeconomic deprivation, racial segregation, and prostate tumor RNA expression of stress-related genes among African American and European American men [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr PR007.

Abstract A043: CDK8/19-regulated transcriptional reprogramming: a druggable driver of castration-resistant prostate cancer

Abstract Androgen deprivation therapy (ADT) is the mainstay of prostate cancer (PCa) treatment. However, most patients with aggressive PCa become resistant to ADT and develop castration-resistant prostate cancer (CRPC). Newer androgen receptor (AR)-targeting CRPC treatments extend survival by only a few months, and metastatic CRPC (mCRPC) remains an incurable disease. Multiple mechanisms of ADT resistance have been identified, among which non-genetic (transcriptional) mechanisms are prominent, due to the high transcriptomic plasticity of PCa and the role of tumor microenvironment (TME) as a determinant of ADT resistance. PCa progression involves changes in the expression of CDK8 and CDK19, enzymatic components of the cyclin-dependent kinase module (CKM), associated with the transcriptional Mediator complex and implicated in transcriptional reprogramming and immune surveillance. We have investigated the roles of CDK8/19 Mediator kinases in CRPC, through bioinformatic analysis of primary PCa and mCRPC and by analyzing the effects of genetic and pharmacological inhibition of CDK8 and CDK19 on tumor growth and gene expression. CDK8 and CDK19 were found to be differentially regulated by androgen, which downregulates CDK8 and upregulates CDK19. Accordingly, CDK8 is decreased and CDK19 increased in primary PCa, where CDK19 is expressed higher than in any other tissues or tumors. However, both CDK19 and CDK8, as well as the other components of the CKM, are upregulated in mCRPC, concordantly with the changes in AR-mediated transcriptional signaling. Selective Mediator kinase inhibitors did not suppress PCa models driven by canonical AR signaling but inhibited in vivo growth of cell line-based and patient-derived xenograft (PDX) models of CRPC. Genetic inactivation of CDK8 and CDK19 suppressed 22Rv1 CRPC tumors in surgically or chemically castrated (but not intact) male NSG mice, whereas the expression of CDK19 or CDK8 reversed this phenotype. Transcriptomic analysis revealed that Mediator kinase inhibition exerted the strongest effects on gene expression in tumors growing in castrated mice, increasing the transcriptomic effects of castration on most of the genes regulated by CDK8/19, while decreasing its effects on some of the genes implicated in PCa progression. A gene signature reflecting Mediator kinase activity in CRPC xenografts correlated with shorter overall survival among mCRPC patients. Systemic treatment with a CDK8/19 inhibitor also affected stromal gene expression; many of these effects were reproduced by Mediator kinase mutagenesis in tumor cells alone, suggesting that Mediator kinases of tumor cells are involved in shaping the TME. Prolonged (up to 300 days) CDK8/19 inhibition induced not only growth inhibition but also shrinkage of CRPC tumors in nude mice (which contain NK cells that are stimulated by CDK8/19 inhibition) and even produced cures in 18-27% of animals. These results warrant the exploration of CDK8/19 Mediator kinase inhibitors for the treatment of the presently incurable CRPC. Citation Format: Jing Li, Thomas Hilimire, Yueying Liu, Lili Wang, Jiaxin Liang, Balazs Gyorffy, Vitali Sikitzhytski, Hao Ji, Li Zhang, Chen Cheng, Xiaokai Ding, Kendall Kerr, Charles Dowling, Gary Schools, Chang-Uk Lim, Eugenia Broude, George Wilding, Michael Lilly, Igor Roninson, Mengqian Chen. CDK8/19-regulated transcriptional reprogramming: a druggable driver of castration-resistant prostate cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr A043.

Abstract C006: Identifying aggressive prostate cancer variants toward reducing cancer disparities

Abstract Background: Prostate cancer (PrCa) has a more detrimental impact on Black men than on men from other races, owing to factors such as limited screening, inadequate treatment received, low involvement in clinical research, and a history of unfair treatment in the healthcare system, among others. Patients with PrCa have a dismal prognosis and are often detected using biomarkers like the prostate-specific antigen (PSA) test and tumor staging. In localized PrCa, there are not enough biomarkers for diagnosis and prognosis. Genomic databases, such as the cBioPortal, may be utilized to conduct studies, evaluate information, discuss findings, and forecast next-generation solutions for effectively combating the increasing prevalence and mortality rates of PrCa. Method: The cBioPortal, containing around 10,366 samples from 22 studies, was explored to identify genomic alterations in genes. We filtered through the datasets and chose prostate adenocarcinoma (MSK, Clin Cancer Res. 2022) and race differences in prostate cancer (MSK, 2021). A total of 3,486 PrCa patients were included in our study but used 1,809 patients. Whereas 1,677 patients were eliminated due to sample types ("not available” NA), race (only black (n= 152) and white (n= 1,657) were included), and sex (males). Primary prostate cancers (n = 994) and metastatic prostate cancers (n = 815) were the two categories of PrCa samples studied. After merging the query results from the two datasets, we identified and estimated the numbers and percentages of overall gene alterations and individual categories of gene alterations. Results: We calculated the prevalence of reported alterations (i.e., mutations, copy number alterations (CNAs), and structural variants) in 10 genes: FOXA1 (AR pathway), TP53, ERG, TMPRSS2 (ETS signaling), PTEN (PI3K-AKT-mTOR signaling), CDK12, KMT2C and BRCA2 (DNA damage repair), SPOP, and MYC (down-regulated by androgen). MYC, FOXA1, SPOP, CDK12, KMT2C, and AR exhibit higher overexpression frequencies in black males than in white men in the profiled samples (P &amp;lt; 0.05). MYC overexpression was observed to be more prevalent in PrCa samples from black patients than samples from white patients, and statistical significance was achieved (9.2% vs 5.6%, p &amp;lt; 0.05). Similarly, black patients had higher levels of PTEN expression than white patients, albeit statistical significance was not achieved (24.0% vs 14.5%, p = 0.08). FOXA1 overexpression is higher in blacks than whites (17.7% vs 15.5%, p = 0.27). CDK12 and KMT2C genomic alterations are more prevalent in black patients than in white patients (60.8% vs 29.8%; 9.9% vs 5.7%, p &amp;lt; 0.05). Using the chi-square (for the racial category and smoking status) and Wilcoxon (for age at diagnosis) statistical tests, clinical factors varied significantly (p&amp;lt;0.001). Conclusion: It is important to understand the genetic underpinnings of disparities in prostate cancer. Our findings support a modest association between genomic alterations in PrCa genes and differential expression by race. Citation Format: Olumide Arigbede, Opeyemi Ogungbola, Sarah Buxbaum, Sara Falzarano, Suhn Rhie. Identifying aggressive prostate cancer variants toward reducing cancer disparities [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr C006.

Examining the Relationship and Prognostic Significance of Cell-Free DNA Levels and the PSMA-Positive Tumor Volume in Men with Prostate Cancer: A Retrospective-Prospective [68Ga]Ga-PSMA-11 PET/CT Study.

Functional imaging with prostate-specific membrane antigen (PSMA) ligands has emerged as the standard imaging method for prostate cancer (PCA). In parallel, the analysis of blood-derived, cell-free DNA (cfDNA) has been shown to be a promising quantitative biomarker of PCA aggressiveness and patient outcome. This study aimed to evaluate the relationship and prognostic value of cfDNA concentrations and the PSMA-positive tumor volume (PSMA-TV) in men with PCA undergoing [68Ga]Ga-PSMA-11 PET/CT imaging. Methods: We recruited 148 men with histologically proven PCA (mean age, 70.7 ± 7.7 y) who underwent [68Ga]Ga-PSMA-11 PET/CT (184.9 ± 18.9 MBq) and blood sampling between March 2019 and August 2021. Among these, 74 (50.0%) had hormone-sensitive PCA and 74 (50.0%) had castration-resistant PCA (CRPC). All patients provided written informed consent before blood sample collection and imaging. The cfDNA was extracted and quantified, and PSMA-expressing tumor lesions were delineated to extract the PSMA-TVs. The Spearman coefficient assessed correlations between PSMA-TV and cfDNA concentrations and cfDNA's relation with clinical parameters. The Kruskal-Wallis test examined the mean cfDNA concentration differences based on PSMA-TV quartiles for significantly correlated patient groups. Log-rank and multivariate Cox regression analyses evaluated the prognostic significance of high and low cfDNA and PSMA-TV levels for overall survival. Results: Weak positive correlations were found between cfDNA concentration and PSMA-TV in the overall group (r = 0.16, P = 0.049) and the CRPC group (r = 0.31, P = 0.007) but not in hormone-sensitive PCA patients (r = -0.024, P = 0.837). In the CRPC cohort, cfDNA concentrations significantly differed between PSMA-TV quartiles 4 and 1 (P = 0.002) and between quartiles 4 and 2 (P = 0.016). Survival outcomes were associated with PSMA-TV (P < 0.0001, P = 0.004) but not cfDNA (P = 0.174, P = 0.12), as per the log-rank and Cox regression analysis. Conclusion: These findings suggest that cfDNA might serve as a biomarker of advanced, aggressive CRPC but does not reliably reflect total tumor burden or prognosis. In comparison, [68Ga]Ga-PSMA-11 PET/CT provides a highly granular and prognostic assessment of tumor burden across the spectrum of PCA disease progression.

Diagnostic role and prognostic impact of PSAP immunohistochemistry: A tissue microarray study on 31,358 cancer tissues from 127 different tumor types

Abstract Introduction/Objective Prostatic specific acid phosphatase (PSAP) protein is produced in prostate epithelial cells and it is used as an immunohistochemical marker for prostate cancer. However, studies have reported PSAP expression to occur in various other tumor entities as well. Methods/Case Report Prostatic specific acid phosphatase (PSAP) protein is produced in prostate epithelial cells and it is used as an immunohistochemical marker for prostate cancer. However, studies have reported PSAP expression to occur in various other tumor entities as well. Results (if a Case Study enter NA) In prostate cancer, PSAP staining was seen in 100% of Gleason 3 + 3, 95.5% Gleason 4 + 4, 93.8% recurrent prostate cancer under androgen deprivation therapy, 91.0% Gleason 5 + 5 and 31.2% small cell neuroendocrine prostate cancer. Reduced PSAP staining was strongly linked to high pT stage, high Gleason grade, lymph node metastasis, early PSA-recurrence (p&amp;lt;0.0001 each),high androgen receptor expression and TMPRSS2:ERG fusions. In multivariate analyses, low PSAP expression was able to predict PSA recurrence independent of pre- and postoperative prognostic markers in ERG negative cancers. In extra-prostatic cancers, PSAP immunostaining was only seen in 3 of 94 (3.2%) neuroendocrine tumors of the pancreas and in 1 of 129 (0.8%) diffuse type gastric adenocarcinomas. Conclusion A positive PSAP immunostaining is highly specific for prostate cancer and reduced PSAP expression is associated with an aggressive prostate cancer phenotype. The independent association of reduced PSAP expression with poor prognosis in ERG negative prostate cancer makes PSAP measurement a candidate marker for prognostic multiparameter panels for prostate cancer.

Temporal evolution reveals bifurcated lineages in aggressive neuroendocrine small cell prostate cancer trans-differentiation

Trans-differentiation from an adenocarcinoma to a small cell neuroendocrine state is associated with therapy resistance in multiple cancer types. To gain insight into the underlying molecular events of the trans-differentiation, we perform a multi-omics time course analysis of a pan-small cell neuroendocrine cancer model (termed PARCB), a forward genetic transformation using human prostate basal cells and identify a shared developmental, arc-like, and entropy-high trajectory among all transformation model replicates. Further mapping with single cell resolution reveals two distinct lineages defined by mutually exclusive expression of ASCL1 or ASCL2. Temporal regulation by groups of transcription factors across developmental stages reveals that cellular reprogramming precedes the induction of neuronal programs. TFAP4 and ASCL1/2 feedback are identified as potential regulators of ASCL1 and ASCL2 expression. Our study provides temporal transcriptional patterns and uncovers pan-tissue parallels between prostate and lung cancers, as well as connections to normal neuroendocrine cell states.

Intracellular Fate of Sub-Toxic Concentration of Functionalized Selenium Nanoparticles in Aggressive Prostate Cancer Cells

Selenium 0 (Se0) is a powerful anti-proliferative agent in cancer research. We investigated the impact of sub-toxic concentrations of Se0 functionalized nanoparticles (SeNPs) on prostate cancer PC-3 cells and determined their intracellular localization and fate. An in-depth characterization of functionalized selenium nanoparticles composition is proposed to certify that no chemical bias relative to synthesis issues might have impacted the study. Selenium is an extremely diluted element in the biological environment and therefore requires high-performance techniques with a very low detection limit and high spatial resolution for intracellular imaging. This was explored with state-of-the-art techniques, but also with cryopreparation to preserve the chemical and structural integrity of the cells for spatially resolved and speciation techniques. Monodisperse solutions of SeNPs capped with bovine serum albumin (BSA) were shown to slow down the migration capacity of aggressive prostate cancer cells compared to polydisperse solutions of SeNPs capped with chitosan. BSA coating could prevent interactions between the reactive surface of the nanoparticles and the plasma membrane, mitigating the generation of reactive oxygen species. The intracellular localization showed interaction with mitochondria and also a localization in the lysosome-related organelle. The SeNPs-BSA localization in mitochondria constitute a possible explanation for our result showing a very significant dampening of the PC-3 cell proliferation capabilities. The purpose of the use of sublethal compound concentrations was to limit adverse effects resulting from high cell death to best evaluate some cellular changes and the fate of these SeNPs on PC-3. Our findings provide new insight to further study the various mechanisms of cytotoxicity of SeNPs.

Uncovering prostate cancer aggressiveness signal in T2-weighted MRI through a three-reference tissues normalization technique.

Quantitative T2-weighted MRI (T2W) interpretation is impeded by the variability of acquisition-related features, such as field strength, coil type, signal amplification, and pulse sequence parameters. The main purpose of this work is to develop an automated method for prostate T2W intensity normalization. The procedure includes the following: (i) a deep learning-based network utilizing MASK R-CNN for automatic segmentation of three reference tissues: gluteus maximus muscle, femur, and bladder; (ii) fitting a spline function between average intensities in these structures and reference values; and (iii) using the function to transform all T2W intensities. The T2W distributions in the prostate cancer regions of interest (ROIs) and normal appearing prostate tissue (NAT) were compared before and after normalization using Student's t-test. The ROIs' T2W associations with the Gleason Score (GS), Decipher genomic score, and a three-tier prostate cancer risk were evaluated with Spearman's correlation coefficient (rS ). T2W differences in indolent and aggressive prostate cancer lesions were also assessed. The MASK R-CNN was trained with manual contours from 32 patients. The normalization procedure was applied to an independent MRI dataset from 83 patients. T2W differences between ROIs and NAT significantly increased after normalization. T2W intensities in 231 biopsy ROIs were significantly negatively correlated with GS (rS = -0.21, p = 0.001), Decipher (rS = -0.193, p = 0.003), and three-tier risk (rS = -0.235, p <0.001). The average T2W intensities in the aggressive ROIs were significantly lower than in the indolent ROIs after normalization. In conclusion, the automated triple-reference tissue normalization method significantly improved the discrimination between prostate cancer and normal prostate tissue. In addition, the normalized T2W intensities of cancer exhibited a significant association with tumor aggressiveness.By improving the quantitative utilization of the T2W in the assessment of prostate cancer on MRI, the new normalization method represents an important advance over clinical protocols that do not include sequences for the measurement of T2 relaxation times.