Aggressive Forms Of Prostate Cancer Research Articles

Curcumin synergistically augments the chemotherapeutic activity of Doxorubicin in prostate cancer cells

Objective Prostate cancer is one of the most commonly diagnosed cancer types in men and many people die every year due to recurring or acquiring aggressive forms of prostate cancer. Numerous chemotherapeutics such as paclitaxel and doxorubicin are commonly used in the treatment of prostate cancer. However, acquired resistance to chemotherapeutics and broad systemic side effects substantially limit their efficacy. Curcumin is one of the most examined phytochemicals of the herbal remedy turmeric. Herein, we aimed to investigate the synergistic capability of curcumin on doxorubicin in prostate cancer cells. Method The human adenocarcinoma cell line LNCaP was used in cell culture studies. Cell viability was examined by WST-1 assay. The protein expression levels of Beclin1, p62/SQSTM1, LC3-I/II, Hrd1, gp78, polyubiquitin, PERK, eIF2, phospho-(Ser51) eIF2, IRE1, XBP-1s, PARP-1, caspase-3, AR, PSA, c-Myc, E-cadherin, N-cadherin and VEGF-A were investigated by immunoblotting assay. Results Our data indicated that co-administration of curcumin with doxorubicin significantly improved the cytotoxic effect of doxorubicin in LNCaP cells. Also, the combination of curcumin and doxorubicin reduced the autophagic flux and remarkably induced endoplasmic reticulum-associated-degradation (ERAD) and unfolded protein response (UPR) signaling. Also, activation of apoptotic proteins PARP-1 and caspase-3 were strongly enhanced by combined treatment in a dose-dependent manner. Moreover, combined treatment markedly decreased AR, PSA, c-Myc and VEGF-A levels. Additionally, the epithelial-mesenchymal transition (EMT) was reduced by decreasing N-cadherin and increasing E-cadherin protein levels. Conclusion Present data strongly suggest that curcumin synergistically improves the anti-cancer features of doxorubicin in prostate cancer cells.

Dietary Fiber Intake and Risk of Advanced and Aggressive Forms of Prostate Cancer: A Pooled Analysis of 15 Prospective Cohort Studies

BackgroundEvidence of an association between dietary fiber intake and risk of advanced and aggressive forms of prostate cancer (PC) and PC mortality is limited. ObjectiveThe aim of this study was to examine associations between intakes of dietary fiber overall and by food source and risk of advanced and aggressive forms of PC. DesignThe study design was a pooled analysis of the primary data from 15 cohorts in 3 continents. Baseline dietary fiber intake was assessed using a validated food frequency questionnaire or diet history in each study. Participants/settingThere were 842,149 men followed for 9 to 22 years between 1985 and 2009 across studies. Main outcome measuresThe primary outcome measures were advanced (stage T4, N1, or M1 or PC mortality), advanced restricted (excluded men with missing stage and those with localized PC who died of PC), and high-grade PC (Gleason score ≥8 or poorly differentiated/undifferentiated) and PC mortality. Statistical analysis performedStudy-specific multivariable hazard ratios (MVHR) were calculated using Cox proportional hazards regression and pooled using random effects models. ResultsIntake of dietary fiber overall, from fruits, and from vegetables was not associated with risk of advanced (n = 4,863), advanced restricted (n = 2,978), or high-grade PC (n = 9,673) or PC mortality (n = 3,097). Dietary fiber intake from grains was inversely associated with advanced PC (comparing the highest vs lowest quintile, MVHR 0.84; 95% CI 0.76-0.93), advanced restricted PC (MVHR 0.85; 95% CI 0.74-0.97), and PC mortality (MVHR 0.78; 95% CI 0.68-0.89); statistically significant trends were noted for each of these associations (P ≤ .03), and a null association was observed for high-grade PC for the same comparison (MVHR 1.00; 95% CI 0.93-1.07). The comparable results were 1.06 (95% CI 1.01-1.10; P value, test for trend = .002) for localized PC (n = 35,199) and 1.05 (95% CI 0.99-1.11; P value, test for trend = .04) for low/intermediate grade PC (n = 34,366). ConclusionsWeak nonsignificant associations were observed between total dietary fiber intake and risk of advanced forms of PC, high-grade PC, and PC mortality. High dietary fiber intake from grains was associated with a modestly lower risk of advanced forms of PC and PC mortality.

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.

Fascin-1 expression is associated with neuroendocrine prostate cancer and directly suppressed by androgen receptor

BackgroundNeuroendocrine prostate cancer (NEPC) is an aggressive form of prostate cancer, arising from resistance to androgen-deprivation therapies. However, the molecular mechanisms associated with NEPC development and invasiveness are still poorly understood. Here we investigated the expression and functional significance of Fascin-1 (FSCN1), a pro-metastasis actin-bundling protein associated with poor prognosis of several cancers, in neuroendocrine differentiation of prostate cancer.MethodsDifferential expression analyses using Genome Expression Omnibus (GEO) database, clinical samples and cell lines were performed. Androgen or antagonist’s cellular treatments and knockdown experiments were used to detect changes in cell morphology, molecular markers, migration properties and in vivo tumour growth. Chromatin immunoprecipitation-sequencing (ChIP-Seq) data and ChIP assays were analysed to decipher androgen receptor (AR) binding.ResultsWe demonstrated that FSCN1 is upregulated during neuroendocrine differentiation of prostate cancer in vitro, leading to phenotypic changes and NEPC marker expression. In human prostate cancer samples, FSCN1 expression is restricted to NEPC tumours. We showed that the androgen-activated AR downregulates FSCN1 expression and works as a transcriptional repressor to directly suppress FSCN1 expression. AR antagonists alleviate this repression. In addition, FSCN1 silencing further impairs in vivo tumour growth.ConclusionCollectively, our findings identify FSCN1 as an AR-repressed gene. Particularly, it is involved in NEPC aggressiveness. Our results provide the rationale for the future clinical development of FSCN1 inhibitors in NEPC patients.

Prostate Cancer Screening Uptake in Transgender Females.

Transgender females (TF) can experience aggressive forms of prostate cancer, but their uptake of prostate-specific antigen (PSA) screening for prostate cancer is not well-known. Although national guidelines recommend PSA screening based on age, they do not specify recommendations based on gender identity. We evaluate and compare factors associated with recent PSA screening between cisgender men (CM) and TF using Behavioral Risk Factor Surveillance System (BRFSS) survey data. BRFSS 2018-2020 data was queried to identify CM and TF older than 40 who provided responses to BRFSS questions asking time since last PSA test and whether a provider discussed PSA advantages and disadvantages. Rates of recent screening, defined as receiving a PSA test in the last 2 years with no current or past history of prostate cancer, were calculated for CM and TF. Ages were grouped as younger than 55, 55-69, and 70 years and older based on national PSA screening guidelines, and a 1:4 age-matched cohort between CM and TF was created. Weighted multivariable logistic regressions to measure effects of gender identity, sociodemographic variables, and healthcare access on the odds of recent screening and were calculated and presented as odds ratios (ORs) [95% confidence intervals]. The age-matched cohort had 1,252 CM and 313 TF; TF had a lower overall screening rate than CM (24% vs. 42.3%). TF and CM had similar rates of primary care visits within the last year (85% vs. 86%), but TF were less likely to report that a PSA screen was recommended to them by a provider (33% vs. 49%, p<0.001). Even among all patients with this PSA screening recommendation, fewer TF were recently screened than CM (63% vs. 78%, p = 0.002). In a multivariable regression model, TF had lower odds of recent screening (OR = 0.5 [0.32-0.76], p<0.001) when compared to CM. Discussion of PSA advantages with a provider had higher odds (OR = 15 [10.6-21.5], p<0.001) while discussion of PSA disadvantages was not significantly associated with screening (OR = 0.84 [0.6-1.2], p = 0.3). A college education had higher odds of recent screening (OR = 2.66 [1.2-6.3], p = 0.02) than no high school education. In a multivariable regression model of TF patients, TF aged 70 years and older had higher odds of recent screening (OR = 2.8 [1.1-7.1], p = 0.002) than TF aged 55-69, with screening rates of 14%, 21% and 60% for the under 55, 55-69, and 70+ age groups, respectively. Similarly, to the overall cohort, provider-led discussion of PSA advantages had the strongest association with recent screening (OR = 15.4 [6.15-43.1], p < 0.001), followed by being college educated (OR = 5.7 [1.5-24.9], p = 0.01). TF patients were screened with PSA at a lower rate than CM. Discussing PSA screening benefits with a provider had the largest effect on recent screening among TF patients, highlighting the provider's role in screening uptake. Future studies should continue to evaluate the effects of provider perceptions and barriers to healthcare access on PSA screening in TF.

Second-Line Systemic Therapy for Highly Aggressive Neuroendocrine Prostate Cancer.

Neuroendocrine prostate cancer (NEPC) is generally an aggressive form of prostate cancer that can arise de novo or develop as a castration-resistant mechanism. While first-line platinum-based chemotherapy is effective against NEPC, its limited response duration and subsequent treatments pose significant clinical challenges. Standard second-line treatments have not been established due to the limited data available. The aim of this review was to reveal the current status of second-line therapy for NEPC. A literature search was conducted using PubMed and Web of Science and a total of 13 articles were included in this review. Prospective and retrospective studies demonstrated that treatment outcome of second-line therapy using platinum with etoposide or docetaxel was unfavorable and progression-free survival was 3 months or shorter. Amrubicin and irinotecan were also frequently used as second-line therapy, however, efficacy of these agents was modest and response duration was less than 6 months. NEPC patients with homologous recombination repair gene alterations may benefit from treatment with poly (ADP-ribose) polymerase (PARP) inhibitors. Ongoing clinical studies investigate various agents, including immune checkpoint inhibitors, molecularly targeted agents, and PARP inhibitors. With the increasing recognition and active biopsy of NEPC lesions, the number of NEPC patients is anticipated to rise. Accumulating more knowledge and experience is crucial in developing novel treatment strategies to combat this disease.

A compendium of Androgen Receptor Variant 7 target genes and their role in Castration Resistant Prostate Cancer.

Persistent androgen receptor (AR) signalling is the main driver of prostate cancer (PCa). Truncated isoforms of the AR called androgen receptor variants (AR-Vs) lacking the ligand binding domain often emerge during treatment resistance against AR pathway inhibitors such as Enzalutamide. This review discusses how AR-Vs drive a more aggressive form of PCa through the regulation of some of their target genes involved in oncogenic pathways, enabling disease progression. There is a pressing need for the development of a new generation of AR inhibitors which can repress the activity of both the full-length AR and AR-Vs, for which the knowledge of differentially expressed target genes will allow evaluation of inhibition efficacy. This review provides a detailed account of the most common variant, AR-V7, the AR-V7 regulated genes which have been experimentally validated, endeavours to understand their relevance in aggressive AR-V driven PCa and discusses the utility of the downstream protein products as potential drug targets for PCa treatment.

Abstract C012: The expression of E-cadherin, B-catenin, N-cadherin, and phospho-Rb S249 as clinical informative biomarkers for the discrimination between indolent and aggressive forms of prostate cancer

Abstract Prostate cancer (PCa) is the second most frequent malignancy in men worldwide1. However, a patient outcome depends on the type of tumor, which can be indolent or aggressive. The indolent PCa is characterized by slow tumor growth and favorable prognosis, whereas the aggressive form is rapidly spread and has high mortality3. However, after a positive biopsy, many of the patients undergo surgery or radiation because the doctor cannot be sure how quickly cancer might grow and spread6. This problem of discriminating between indolent and aggressive PCa has resulted in a significant problem of overtreating those patients with the indolent form of the disease. Thus, biomarkers that aid in the decision-making process and criteria regarding active surveillance in very low-, low-, and favorable intermediate-risk PCa face a large unmet need7. We aim to minimize the overtreatment of patients with indolent disease that will not require significant treatment and qualify for active surveillance as a long-term goal. For this purpose, we evaluated the clinical relevance of identified biomarkers that could be used in the clinic for the risk classification of indolent and aggressive PCa. We hypothesize that the combination of phospho-Rb S249, N-cadherin, E-cadherin, and β-catenin expression on PCa adenocarcinoma will serve as a clinical tool for the classification of aggressive tumors that induces metastasis or as indolent tumors that may qualify for active surveillance. As part of our methodology, we have conducted immunohistochemistry (N=182) against the expression of these biomarkers on PCa tumor microarrays (TMA’s). To assess if the expression of these biomarkers could correlate with any of the patient’s clinical parameters (stage, grade, tumor size, lymph nodes metastasis, metastasis to distant sites, Gleason score, and Gleason grade), we conducted correlation coefficient analyses. In addition, we created a linear regression model to determine if the combined proteins could precisely predict the patients' staging, grade, or Gleason score. Results have shown that the combination of phospho-Rb S249, N-cadherin, E-cadherin, and β-catenin had a precision of correctly predicting the staging of the patients by a 53.83%, and adding the TNM increases the accuracy to an 83.21% (N=413). Additionally, we identified that E-cadherin and β-catenin negatively correlated with the tumor size, grade, stage, Gleason grade, and Gleason score of the patients. N-cadherin and phospho-Rb S249 positively correlate with the tumor size, stage, and Gleason grade, and phospho-Rb S249 positively correlates with tumor size and stage. These results suggest that the expression of phospho-Rb S249, N-cadherin, E-cadherin, and β-catenin could potentially create a Prostate Proteomic Score (PPS) for the risk classification of indolent and aggressive PCa tumors. These findings will enhance the clinical decision of which patients should be treated or undergo active surveillance. Citation Format: Sheila Marie Valle-Cortes, Pedro Santiago, Gilberto Ruiz-Deya, Carlos Diaz-Osterman, Jaileene Perez-Morales. The expression of E-cadherin, B-catenin, N-cadherin, and phospho-Rb S249 as clinical informative biomarkers for the discrimination between indolent and aggressive forms of prostate cancer [abstract]. In: Proceedings of the 15th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2022 Sep 16-19; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr C012.

Unveiling genetic variant-level biomarkers for aggressive prostate cancer

Prostate cancer (PCa) represents the second most frequently diagnosed malignancy among males in the United States and ranks fourth in terms of general cancer prevalence on a global scale. A critical assessment of existing literature indicates a notable deficiency in the identification of biomarkers that are uniquely associated with aggressive forms of PCa. The principal objective of this paper is to discover biomarkers at the genetic variant level by deploying statistical methodologies to determine associations between such variants and the aggressive and lethal form of the disease. Employing the multiple comparisons technique, we identified four variants that were statistically significant at the 5 % significance level. Furthermore, we utilized Over-representation analysis (ORA) to identify the biological pathways linked with these genetic variants. To validate our findings, we employed a decision tree algorithm on an independent dataset comparing the proposed biomarkers with random subsets of variants. Results have shown that the predictive accuracy of aggressive samples was 97 % for the proposed biomarkers, while this figure dropped to 67 % when randomly selected variants were considered.

Androgen-Independent Prostate Cancer Is Sensitive to CDC42-PAK7 Kinase Inhibition.

Prostate cancer is a common form of cancer in men, and androgen-deprivation therapy (ADT) is often used as a first-line treatment. However, some patients develop resistance to ADT, and their disease is called castration-resistant prostate cancer (CRPC). Identifying potential therapeutic targets for this aggressive subtype of prostate cancer is crucial. In this study, we show that statins can selectively inhibit the growth of these CRPC tumors that have lost their androgen receptor (AR) and have overexpressed the RNA-binding protein QKI. We found that the repression of microRNA-200 by QKI overexpression promotes the rise of AR-low mesenchymal-like CRPC cells. Using in silico drug/gene perturbation combined screening, we discovered that QKI-overexpressing cancer cells are selectively vulnerable to CDC42-PAK7 inhibition by statins. We also confirmed that PAK7 overexpression is present in prostate cancer that coexists with hyperlipidemia. Our results demonstrate a previously unseen mechanism of action for statins in these QKI-expressing AR-lost CRPCs. This may explain the clinical benefits of the drug and support the development of a biology-driven drug-repurposing clinical trial. This is an important finding that could help improve treatment options for patients with this aggressive form of prostate cancer.

Radiotherapy after radical prostatectomy

Local treatment following radical prostatectomy used in prostate cancer patients with risk factors of recurrence or with biochemical recurrence and/or local recurrence consists of adjuvant and salvage radiotherapy. The postprostatectomy biochemical failure, according to some studies based on ten years of follow-up, is estimated at one-third of patients. It remains challenging to extract those patients who may benefit from implementing radiotherapy while minimizing the risk of overtreatment. Adjuvant radiotherapy is considered in a situation of the absence of biochemical recurrence with the presence of high-risk features in pathological staging defined as positive surgical margins (R1), extraprostatic extension (pT3a), or seminal vesicle invasion (pT3b) and Gleason score 8-10. Failure rate after RP is found approximately in 50% of men diagnosed with adverse pathologic features. It is recommended to implement adjuvant radiotherapy in case of very aggressive form of prostate cancer (pT3b, Gleason 8-10) without awaiting biochemical recurrence. However, salvage radiotherapy represents a therapeutic option for patients experiencing biochemical recurrence in case of no distant metastasis. Monitoring of serum PSA levels in each individual is crucial in deciding whether salvage radiotherapy is needed. The effectiveness of treatment increases along with early initiation of radiation therapy. Current guidelines developed by NCCN and EAU regard conversion of PSA from undetectable to detectable level as a sign of cancers’ recurrence. In addition, prostate-specific membrane antigen (PSMA) PET should be used as a part of modern imaging diagnostics for a precise determination of disease extent.

Testing the generalizability of ancestry-specific polygenic risk scores to predict prostate cancer in sub-Saharan Africa

BackgroundGenome-wide association studies do not always replicate well across populations, limiting the generalizability of polygenic risk scores (PRS). Despite higher incidence and mortality rates of prostate cancer in men of African descent, much of what is known about cancer genetics comes from populations of European descent. To understand how well genetic predictions perform in different populations, we evaluated test characteristics of PRS from three previous studies using data from the UK Biobank and a novel dataset of 1298 prostate cancer cases and 1333 controls from Ghana, Nigeria, Senegal, and South Africa.ResultsAllele frequency differences cause predicted risks of prostate cancer to vary across populations. However, natural selection is not the primary driver of these differences. Comparing continental datasets, we find that polygenic predictions of case vs. control status are more effective for European individuals (AUC 0.608–0.707, OR 2.37–5.71) than for African individuals (AUC 0.502–0.585, OR 0.95–2.01). Furthermore, PRS that leverage information from African Americans yield modest AUC and odds ratio improvements for sub-Saharan African individuals. These improvements were larger for West Africans than for South Africans. Finally, we find that existing PRS are largely unable to predict whether African individuals develop aggressive forms of prostate cancer, as specified by higher tumor stages or Gleason scores.ConclusionsGenetic predictions of prostate cancer perform poorly if the study sample does not match the ancestry of the original GWAS. PRS built from European GWAS may be inadequate for application in non-European populations and perpetuate existing health disparities.

Immunoarray Measurements of Parathyroid Hormone-Related Peptides Combined with Other Biomarkers to Diagnose Aggressive Prostate Cancer.

Parathyroid hormone-related peptide (PTHrP) is related to bone metastasis and hypercalcemia in prostate and breast cancers and should be an excellent biomarker for aggressive forms of these cancers. Current clinical detection protocols for PTHrP are immunoradiometric assay and radioimmunoassay but are not sensitive enough to detect PTHrPs at early stages. We recently evaluated a prostate cancer biomarker panel, including serum monocyte differentiation antigen (CD-14), ETS-related gene protein, pigment epithelial-derived factor, and insulin-like growth factor-1, with promise for identifying aggressive prostate cancers. This panel predicted the need for patient biopsy better than PSA alone. In the present paper, we report an ultrasensitive microfluidic assay for PTHrPs and evaluate their diagnostic value and the value of including them with our prior biomarker panel to diagnose aggressive forms of prostate cancer. The immunoarray features screen-printed carbon sensor electrodes coated with 5 nm glutathione gold nanoparticles with capture antibodies attached. PTHrPs are bound to a secondary antibody attached to a polyhorseradish peroxidase label and delivered to the sensors to provide high sensitivity when activated by H2O2 and a mediator. We obtained an unprecedented 0.3 fg mL-1 limit of detection for PTHrP bioactive moieties PTHrP 1-173 and PTHrP 1-86. We also report the first study of PTHrPs in a large serum pool to identify aggressive malignancies. In assays of 130 human patient serum samples, PTHrP levels distinguished between aggressive and indolent prostate cancers with 83-91% clinical sensitivity and 78-96% specificity. Logistic regression identified the best predictive model as a combination of PTHrP 1-86 and vascular endothelial growth factor-D. PTHrP 1-173 alone also showed a high ability to differentiate aggressive and indolent cancers.

Role of monocarboxylate transporters and glucose transporters in prostate cancer.

Currently, research of new diagnostic approaches to detect clinically significant prostate cancer is relevant because of the importance of early detection of aggressive forms of the disease, often challenging, even when using modern diagnostic tools. The aim of this review is to present the current knowledge regarding monocarboxylate transporters' and glucose transporters' expression as a component of glycolytic phenotype definition in prostate cancer cells. We searched PubMed and Scopus databases. Twenty-six articles from 2003 to 2022 were included. Literature research and selection were carried out based on the recommendations of the PRISMA statement. The presence of "lactate shuttle" in the tumor tissue is associated with a worse prognosis. Increased expression of MCT2, MCT4, GLUT1, and down-regulation of GLUT3 are associated with prostate adenocarcinoma. MCT4 expression level correlates with the grade of tumor malignancy and disease prognosis. Up-regulation of GLUT1 and MCT4 is typical for hormone-resistant prostate cancer. Inhibition of MCT1 and MCT4 and GLUT1 in prostate cancer cells reduces their metabolic activity and growth rate, a suitable novel approach for targeted therapy. Review of the current studies showed that expression of certain MCTs and GLUTs types are associated with prostate cancer and some of them correlate with high malignancy and poor prognosis. Detection by immunohistochemistry of these transporters could represent a new diagnostic tool to identify aggressive forms of prostate cancer, and a novel therapeutic target for selective drugs.

Abstract 6001: Phosphorylation of the retinoblastoma protein at Serine 249 and the cadherin switch as clinically informative biomarkers for the discrimination between indolent and aggressive forms of prostate cancer

Abstract Prostate cancer (PCa) is the second most frequent malignancy in men worldwide. This disease is the cause of most cancer death among Puerto Rican men, representing 18.9% of overall cancer deaths. However, a patient outcome depends on the type of tumor, which can be indolent or aggressive. The indolent PCa is of slow tumor growth and favorable prognosis, whereas the aggressive form is of rapid tumor spread and high mortality. The discrimination between the indolent and aggressive forms of PCa has resulted in a significant problem of overtreating those patients with the indolent form of the disease. Thus, biomarkers that aid in the decision-making process regarding active surveillance in very low-, low-, and favorable intermediate-risk PCa face a large unmet need. For this purpose, we evaluate the expression of phospho-Rb S249 and epithelial to mesenchymal transition markers (E-cadherin, N-cadherin, B-catenin) to create a combination that can help distinguish between the indolent and aggressive forms of PCa. We hypothesize that the biomarkers E-cadherin, and B-catenin could be useful to identify indolence among PCa patients, whereas phospho-Rb S249 and N-cadherin could identify the aggressive form of the disease. As part of our methodology, we have conducted immunohistochemistry (N=182) against the expression of these biomarkers on PCa tumor microarrays (TMA’s). Correlation coefficient analyses were conducted to assess if the expression of these biomarkers could correlate with any of the patient’s clinical parameters (stage, grade, tumor size, lymph nodes metastasis, metastasis to distant sites, Gleason score, and Gleason grade). In addition, we created a linear regression analysis to determine if the combined proteins could precisely predict the staging, grade, or Gleason score of the patients. Results have shown that the combination of phospho-Rb S249, N-cadherin, E-cadherin, and B-catenin had a precision of 68% correctly predicting the staging of the patients, and adding the tumor size, lymph nodes metastasis, and metastasis to distant sites to the equation increased the prediction to a 96%. Additionally, we identified that E-cadherin and B-catenin negatively correlated with the tumor size, grade, stage, Gleason grade, and Gleason score of the patients. Whereas N-cadherin and phospho-Rb S249 positively correlate with the tumor size, stage, and Gleason grade. These results suggest that the expression of phospho-Rb S249, N-cadherin, E-cadherin, and B-catenin could be used as a potential tool to discriminate between the indolent and aggressive forms of PCa. This will contribute to enhancing the clinical decision of which patients should be treated or undergo active surveillance. Citation Format: Sheila M. Valle Cortes, Pedro Santiago Cardona, Carlos Diaz Osterman, Harold Saavedra, Shannalee R. Martinez, Gilberto Ruiz Deya, Jaileene Perez Morales, Adam B. Murphy. Phosphorylation of the retinoblastoma protein at Serine 249 and the cadherin switch as clinically informative biomarkers for the discrimination between indolent and aggressive forms of prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 6001.

Prostate cancer histopathology using label-free multispectral deep-UV microscopy quantifies phenotypes of tumor aggressiveness and enables multiple diagnostic virtual stains

Identifying prostate cancer patients that are harboring aggressive forms of prostate cancer remains a significant clinical challenge. Here we develop an approach based on multispectral deep-ultraviolet (UV) microscopy that provides novel quantitative insight into the aggressiveness and grade of this disease, thus providing a new tool to help address this important challenge. We find that UV spectral signatures from endogenous molecules give rise to a phenotypical continuum that provides unique structural insight (i.e., molecular maps or “optical stains") of thin tissue sections with subcellular (nanoscale) resolution. We show that this phenotypical continuum can also be applied as a surrogate biomarker of prostate cancer malignancy, where patients with the most aggressive tumors show a ubiquitous glandular phenotypical shift. In addition to providing several novel “optical stains” with contrast for disease, we also adapt a two-part Cycle-consistent Generative Adversarial Network to translate the label-free deep-UV images into virtual hematoxylin and eosin (H&E) stained images, thus providing multiple stains (including the gold-standard H&E) from the same unlabeled specimen. Agreement between the virtual H&E images and the H&E-stained tissue sections is evaluated by a panel of pathologists who find that the two modalities are in excellent agreement. This work has significant implications towards improving our ability to objectively quantify prostate cancer grade and aggressiveness, thus improving the management and clinical outcomes of prostate cancer patients. This same approach can also be applied broadly in other tumor types to achieve low-cost, stain-free, quantitative histopathological analysis.

Association of RB1 mutational status with overall genomic landscape in neuroendocrine prostate cancer (NEPC).

5063 Background: NEPC is a high-grade aggressive form of prostate cancer. We queried whether RB1 mutation status would impact the genomic features of NEPC in RB1 mutated vs non-mutated cases. Methods: From a series of 13,496 cases of clinically advanced PC, we identified 415 cases (3.1%) with a diagnosis of small cell PC or NEPC as determined by the submitting physician. They were sequenced using a hybrid capture-based FDA-approved clinical genomic profiling (CGP) assay to detect all classes of genomic alterations (GA). Tumor mutational burden (TMB) was determined on 0.8 Mbp of sequenced DNA and microsatellite instability (MSI) was determined on 95 loci. PD-L1 expression was determined by IHC (Dako 22C3) with low tumor cell positive staining 1-49% and high staining ≥50% expression. Results: 253 (61%) of NEPC feature GA in RB1 (RB1 mut+). This contrasts with a 5.8% frequency of RB1 GA in the non-NEPC (P &lt;.0001). The RB1 mut+ NEPC featured a slightly greater number of pathogenic GA/tumor than the RB1 mut- NEPC (5.1 vs 4.2). Age and TMPRSS2-ERG fusion frequency were similar between the groups. RB1 Mut- NEPC was associated with significantly higher amplifications (amp) and total GA in AR compared to RB1 mut+ NEPC. RB1 mut+ NEPC featured significantly greater frequency of PTEN GA. GA frequencies in targetable kinases and DNA repair GA including BRCA1/2 and ATM linked to PARP inhibitor (PARPi) response were similar in both groups. For potential immune-oncology (IO) biomarkers, RB1 Mut+ NEPC featured significantly greater frequency of positive PD-L1 expression and lower frequencies of MDM2 and CDK12 GA. CD274 ( PD-L1) amplification, MSI-high status and cases with TMB ≥10 mut/Mb were uncommon in both groups. gLOH was higher in RB1 mut+ than RB1 mut- (P =.005). There were more cases of non-European ancestry in the RB1 mut- group. APC I1307K mut were found in 3/162 (1.9%) RB1 mut- NEPC only. Conclusions: In NEPC, the presence of RB1 mutation is associated with various GA that may have clinical relevance. Further study of RB1 status as a guide in trial designs on therapy selection for men with NEPC appears warranted. [Table: see text]

New TRPM8 blockers exert anticancer activity over castration-resistant prostate cancer models

TRPM8 has recently emerged as a druggable target in prostate cancer (PC) and TRPM8 modulators have been proposed as potential anticancer agents in this pathology. We have recently demonstrated their effectiveness in a castration-resistant prostate cancer (CRPC) model that is usually resistant to androgen deprivation therapy (ADT) and is considered the most aggressive form of PC. This is why the discovery of selective, effective, and potent TRPM8 modulators would improve the molecular arsenal in support of PC standard-of-care treatments. In the present paper we describe the design and the synthesis of a new series of TRPM8 antagonists, preliminarily characterized in vitro for their potency and selectivity by fluorimetric calcium assays. The preliminary screening allowed the identification of several potent (0.11 μM < IC50 < 0.49 μM) and selective compounds. The most potent derivatives were further characterized by patch-clamp electrophysiology assays, confirming their noteworthy activity. Moreover, the behavior of these compounds was investigated in 2D and 3D models of PC. These TRPM8 antagonists showed remarkable efficacy in inhibiting the growth induced by androgen in various PC cells as well as in CRPC models, confirming their potential as anticancer agents.

High eEF1A1 Protein Levels Mark Aggressive Prostate Cancers and the In Vitro Targeting of eEF1A1 Reveals the eEF1A1-actin Complex as a New Potential Target for Therapy.

Although the eukaryotic elongation factor eEF1A1 plays a role in various tumours, there is little information on its prognosis/therapeutic value in prostate carcinoma. In high-grade and castration-resistant prostate carcinoma (CRPC), the identification of novel therapeutic markers/targets remains a priority. The expression of eEF1A1 protein was determined in formalin-fixed, paraffin-embedded prostate cancer and hyperplasia tissue by IHC. The role of eEF1A1 was investigated in a cellular model using a DNA aptamer (GT75) we previously developed. We used the aggressive CRPC cancer PC-3 and non-tumourigenic PZHPV-7 lines. Cytotoxicity was measured by the MTS assay and eEF1A1 protein levels by in-cell Western assays. The mRNA levels of eEF1A1 were measured by qPCR and ddPCR. Higher expression of eEF1A1 was found in Gleason 7–8 compared with 4–6 tissues (Gleason ≥ 7, 87% versus Gleason ≤ 6, 54%; p = 0.033). Patients with a high expression of eEF1A1 had a worse clinical outcome. In PC-3, but not in PZHPV-7, GT75 decreased cell viability and increased autophagy and cell detachment. In PC-3 cells, but not in PZHPV-7, GT75 mainly co-localised with the fraction of eEF1A1 bound to actin. Overexpression of the eEF1A1 protein can identify aggressive forms of prostate cancer. The targeting of eEF1A1 by GT75 impaired cell viability in PC-3 cancer cells but not in PZHPV-7 non-tumourigenic cells, indicating a specific role for the protein in cancer survival. The eEF1A1–actin complexes appear to be critical for the viability of PC-3 cancer cells, suggesting that eEF1A1 may be an attractive target for therapeutic strategies in advanced forms of prostate cancer.

Raloxifene Suppresses Tumor Growth and Metastasis in an Orthotopic Model of Castration-Resistant Prostate Cancer.

Androgen receptor (AR)-castrate-resistant prostate cancer (CRPC) is an aggressive form of prostate cancer that does not have clinically approved targeted treatment options. To this end, the cytotoxic potential of raloxifene and the synthetic curcumin derivative 2,6-bis (pyridin-4-ylmethylene)-cyclohexanone (RL91) was examined in AR-(PC3 and DU145) cells and AR+ (LnCaP) CRPC cells. The results showed that both raloxifene and RL91 elicited significant cytotoxicity across three cell lines with the lowest EC50 values in PC3 cells. Additionally, the two drugs were synergistically cytotoxic toward the PC3, DU-145 and LNCaP cell lines. To determine the effect of the drug combination in vivo, an orthotopic model of CRPC was used. Male mice were injected with PC3 prostate cancer cells and then treated with vehicle (5 mL/kg), raloxifene (8.5 mg/kg, po), RL91 (8.5 mg/kg, po) or a combination of raloxifene and RL91 for six weeks. Sham animals were subjected to the surgical procedure but were not implanted with PC3 cells. The results showed that raloxifene decreased tumor size and weight as well as metastasis to renal lymph nodes. However, combination treatment reversed the efficacy of raloxifene as tumor volume and metastasis returned to control levels. The results suggest that raloxifene has tumor suppressive and anti-metastatic effects and has potential for further clinical use in AR-CRPC.