Prostate cancer

Molecular Pathology of Prostate Cancer

Molecular profiling studies have shed new light on the complex biology of prostate cancer. Genomic studies have highlighted that structural rearrangements are among the most common recurrent alterations. In addition, both germline and somatic mutations in DNA repair genes are enriched in patients with advanced disease. Primary prostate cancer has long been known to be multifocal, but recent studies demonstrate that a large fraction of prostate cancer shows evidence of multiclonality, suggesting that genetically distinct, independently arising tumor clones coexist. Metastatic prostate cancer shows a high level of morphologic and molecular diversity, which is associated with resistance to systemic therapies. The resulting high level of intratumoral heterogeneity has important implications for diagnosis and poses major challenges for the implementation of molecular studies. Here we provide a concise review of the molecular pathology of prostate cancer, highlight clinically relevant alterations, and discuss opportunities for molecular testing.

A pictorial essay of PI-RADS pearls and pitfalls: toward less ambiguity and better practice

Prostate Imaging Reporting and Data System (PI-RADS) was designed to standardize the interpretation of multiparametric magnetic resonance imaging (MRI) of the prostate, aiding in assessing the probability of clinically significant prostate cancer. By providing a structured scoring system, it enables better risk stratification, guiding decisions regarding the need for biopsy and subsequent treatment options. In this article, we explore both the strengths and weaknesses of PI-RADS, offering insights into its updated diagnostic performance and clinical applications, while also addressing potential pitfalls using diverse, representative MRI cases.

Risk factors for prostate cancer: An umbrella review of prospective observational studies and mendelian randomization analyses

BACKGROUND

The incidence of prostate cancer is increasing in older males globally. Age, ethnicity, and family history are identified as the well-known risk factors for prostate cancer, but few modifiable factors have been firmly established. The objective of this study was to identify and evaluate various factors modifying the risk of prostate cancer reported in meta-analyses of prospective observational studies and mendelian randomization (MR) analyses.

METHODS AND FINDINGS

We searched PubMed, Embase, and Web of Science from the inception to January 10, 2022, updated on September 9, 2023, to identify meta-analyses and MR studies on prostate cancer. Eligibility criteria for meta-analyses were (1) meta-analyses including prospective observational studies or studies that declared outcome-free at baseline; (2) evaluating the factors of any category associated with prostate cancer incidence; and (3) providing effect estimates for further data synthesis. Similar criteria were applied to MR studies. Meta-analysis was repeated using the random-effects inverse-variance model with DerSimonian-Laird method. Quality assessment was then conducted for included meta-analyses using AMSTAR-2 tool and for MR studies using STROBE-MR and assumption evaluation. Subsequent evidence grading criteria for significant associations in meta-analyses contained sample size, P values and 95% confidence intervals, 95% prediction intervals, heterogeneity, and publication bias, assigning 4 evidence grades (convincing, highly suggestive, suggestive, or weak). Significant associations in MR studies were graded as robust, probable, suggestive, or insufficient considering P values and concordance of effect directions. Finally, 92 selected from 411 meta-analyses and 64 selected from 118 MR studies were included after excluding the overlapping and outdated studies which were published earlier and contained fewer participants or fewer instrument variables for the same exposure. In total, 123 observational associations (45 significant and 78 null) and 145 causal associations (55 significant and 90 null) were categorized into lifestyle; diet and nutrition; anthropometric indices; biomarkers; clinical variables, diseases, and treatments; and environmental factors. Concerning evidence grading on significant associations, there were 5 highly suggestive, 36 suggestive, and 4 weak associations in meta-analyses, and 10 robust, 24 probable, 4 suggestive, and 17 insufficient causal associations in MR studies. Twenty-six overlapping factors between meta-analyses and MR studies were identified, with consistent significant effects found for physical activity (PA) (occupational PA in meta: OR = 0.87, 95% CI: 0.80, 0.94; accelerator-measured PA in MR: OR = 0.49, 95% CI: 0.33, 0.72), height (meta: OR = 1.09, 95% CI: 1.06, 1.12; MR: OR = 1.07, 95% CI: 1.01, 1.15, for aggressive prostate cancer), and smoking (current smoking in meta: OR = 0.74, 95% CI: 0.68, 0.80; smoking initiation in MR: OR = 0.91, 95% CI: 0.86, 0.97). Methodological limitation is that the evidence grading criteria could be expanded by considering more indices.

CONCLUSIONS

In this large-scale study, we summarized the associations of various factors with prostate cancer risk and provided comparisons between observational associations by meta-analysis and genetically estimated causality by MR analyses. In the absence of convincing overlapping evidence based on the existing literature, no robust associations were identified, but some effects were observed for height, physical activity, and smoking.

Improving the identification of high-risk non-metastatic castration-resistant prostate cancer patients in clinical practice

Non-metastatic castration-resistant prostate cancer (nmCRPC) represents a challenging disease state in prostate cancer care. nmCRPC patients with a high risk of progression to metastatic disease who are identified by a prostate-specific antigen doubling time (PSADT) ≤10 months are eligible for treatment with the novel androgen receptor inhibitors (ARIs), shown to delay disease progression and extend survival. However, nmCRPC is often unexploited in clinical practice due to a lack of standardization in the methodology and in the tools used for its identification. In this article, a group of Urology and Oncology specialists with acknowledged expertise in prostate cancer reviews the state of the art in the management of high-risk nmCRPC patients, identifies gaps and unmet needs, and proposes strategies to optimize the identification of this patient subgroup in the clinical practice and improve their health outcomes.

Histone methyltransferase SUV39H2 regulates apoptosis and chemosensitivity in prostate cancer through AKT/FOXO signaling pathway

Prostate cancer (PCa) is one of the most common malignant tumors that exhibit both chemoresistance and recurrence. SUV39H2 is highly expressed in many types of human tumors, but its role in the development and progression of PCa has never been clarified. The aim of this study is to elucidate the role of SUV39H2 in the development and progression of PCa, its association with the AKT/FOXO signaling pathway, and its potential implications for PCa diagnosis and treatment. SUV39H2 expression was analyzed in The Cancer Genome Atlas (TCGA) and genotype tissue expression pan-cancer data. The TCGA database was evaluated for SUV39H2 enrichment and its correlation to immune cell infiltration. SUV39H2 levels in PCa tissues and control tissues were determined in 30 patients using qPCR and IHC. Clinical relevance was assessed via The Cancer Genome Atlas (TCGA). In vitro assessments including colony formation assays, Western Blot analysis, CCK-8 assays, and flow cytometry were utilized to establish SUV39H2's contribution to PCa cell growth. The influence of SUV39H2 on PC3 and DU145 cell proliferation was assessed through a cell line-derived xenograft model. Sphere formation assays and qPCR were employed to delineate SUV39H2's role in PCa stemness and chemosensitivity. In vitro macrophage polarization assays provided insights into SUV39H2's association with M2 macrophages, while enrichment analysis shed light on its role in FOXO signaling. PCa tissues expressed higher levels of SUV39H2 than normal tissues. By knocking down SUV39H2, PCa cells were made more chemosensitive to docetaxel and cell proliferation and stemness were inhibited. Additionally, SUV39H2 knockdown significantly inhibited in vivo PCa cell growth and inhibited the polarization of macrophages. Furthermore, SUV39H2 was found to regulate AKT/FOXO signaling by increasing Akt and FOXO3a phosphorylation. Our findings highlight SUV39H2's role in PCa cell apoptosis and chemosensitivity mainly by regulating the AKT/FOXO signaling pathway and suggest that SUV39H2 could be a potential target for PCa diagnosis and treatment.

New 1H-pyrazolo[3,4-d]pyrimidin-1-yl)ethyl)-2-phenylisoquinoline-1(2H)-ones as Phosphoinositide 3-kinase Inhibitors for Treating Cancer and Other Diseases

The patent describes novel useful compounds, such as PI3K protein kinase inhibitors, in particular as PI3K delta (δ) and/or gamma (γ) protein kinase modulators. The present disclosure also provides methods for preparing PI3K protein kinase inhibitors, pharmaceutical compositions containing them, and methods of treatment, prevention, and amelioration of PI3K kinase-mediated diseases, and disorders.

Incidence of Prostate Cancer in Transgender Women Undergoing Androgen Deprivation Therapy: A Review

Transwomen frequently undergo androgen deprivation therapy (ADT) incorporated with oestrogen, but they are still prone to the occurrence of prostatic cancer since the prostate remains intact. The probability of this clinical condition reduces as compared with the general male population. This study aimed to study the occurrence of prostatic malignancy under hormonal therapy such as ADT in transwomen. An extensive literature search was performed using online searches on transgender health, centring on the incidence, diagnosis, treatment and management of prostate cancer in transgender women. Original articles from 1975 to 2022 were searched using PubMed, Scopus, EMBASE, DOAJ and Cochrane databases. Physical, mental and communal deliberation of health development is the major constituent of trans-health. It exhibits a fivefold reduction in prostatic malignancies in transwomen undergoing hormonal therapy contrasted with the extensive male community of indistinguishable age.

Identification of senescence-related lncRNA prognostic index correlating with prognosis and radiosensitivity in prostate cancer patients

BACKGROUND

An increasing number of studies are shown how crucial a role cellular senescence plays in tumor development. In this study, we developed a senescence-related lncRNA prognostic index (SRLPI) to forecast radiosensitivity and the probability of biochemical recurrence (BCR) in patients with prostate cancer (PCa).

METHODS

PCa cohorts in TCGA and GEO databases were downloaded. Senescence-and prognosis-related lncRNA with differential expression in tumor and normal samples were identified and used to establish the SRLPI score. Mutation landscape, function pathway, tumor stemness and heterogeneity and tumor immune microenvironment were also analyzed. We performed the analysis using R 3.6.3 and the appropriate tools.

RESULTS

A SRLPI score was constructed based on SNHG1 and MIAT in the TCGA cohort. Our classification of PCa patients into high- and low-risk groups was based on the median SRLPI score. When compared to the low-SRLPI group, the high-SRLPI group was more vulnerable to BCR (HR: 3.33). In terms of BCR-free survival and metastasis-free survival, the GSE116918 showed similar findings. Surprisingly, the SRLPI score demonstrated a high level of radiosensitivity for diagnosis (AUC: 0.98). Age, Gleason score, T stage, N stage, positive lymph nodes, and residual tumor were all significantly greater in patients with high SRLPI scores. Furthermore, this score was significantly related to markers of senescence. Protein secretion and androgen response were found to be substantially enriched in the low-SRLPI group, whereas E2F targets were found to be strongly enriched in the high-SRLPI group for pathway analysis. For the tumor microenvironment assessment, B cells, CD8+ T cells, immune score and TIDE score were positively related to SRLPI score while endothelial level was negatively associated with SRLPI score with statistical significance.

CONCLUSIONS

We developed a SRLPI score that was related to prognosis and radiosensitivity and might be helpful in clinical practice.

NKX3.1 Expression Contributes to Epithelial-Mesenchymal Transition of Prostate Cancer Cells

Studies demonstrate that inflammation synergizes with high-grade aggressive prostate tumor development and ultimately metastatic spread, in which a lot of work has been done in recent years. However, the clear mechanism of inflammation inciting prostate cancer remains largely uncharacterized. Our previous study has shown that the conditioned media (CM)-mediated LNCaP cell migration is partially correlated with the loss of expression of the tumor suppressor NKX3.1. Here, we continue to investigate the inflammation-mediated migration of prostate cancer cells, and the role of NKX3.1 in this process to gain insights into cell migration-related changes comprehensively. Earlier, the model of inflammation in the tumor microenvironment have been optimized by our research group; here, we continue to investigate the time-dependent effect of CM exposure together with NKX3.1 changes, in which we observed that these changes play important roles in gaining heterogeneous epithelial-to-mesenchymal transition (EMT) phenotype. Hence, this is an important parameter of tumor progression; we depleted NKX3.1 expression using the CRISPR/Cas9 system and examined the migrating cell clusters after exposure to inflammatory cytokines. We found that the migrated cells clearly demonstrate reversible loss of E-cadherin expression, which is consistent with subsequent vimentin expression alterations in comparison to control cells. Moreover, the data suggest that the AR-mediated transcriptional program also contributes to mesenchymal-to-epithelial transition (MET) in prostate cancer progression. Furthermore, the quantitative proteomic analysis showed that migrated subpopulations from the same cell line presented different phenotypes in which the proteins overexpressed are involved in cell metabolism and RNA processing. According to KEGG pathway analysis, the ABC transporters were found to be the most significant. Thus, the dynamic process of cellular migration favors diverse genetic compositions under changing tumor microenvironments. The different levels of invasiveness are supported by shifting the cells in between these EMT and MET phenotypes.

The DACH1 gene is frequently deleted in prostate cancer, restrains prostatic intraepithelial neoplasia, decreases DNA damage repair, and predicts therapy responses

Prostate cancer (PCa), the second leading cause of death in American men, includes distinct genetic subtypes with distinct therapeutic vulnerabilities. The DACH1 gene encodes a winged helix/Forkhead DNA-binding protein that competes for binding to FOXM1 sites. Herein, DACH1 gene deletion within the 13q21.31-q21.33 region occurs in up to 18% of human PCa and was associated with increased AR activity and poor prognosis. In prostate OncoMice, prostate-specific deletion of the Dach1 gene enhanced prostatic intraepithelial neoplasia (PIN), and was associated with increased TGFβ activity and DNA damage. Reduced Dach1 increased DNA damage in response to genotoxic stresses. DACH1 was recruited to sites of DNA damage, augmenting recruitment of Ku70/Ku80. Reduced Dach1 expression was associated with increased homology directed repair and resistance to PARP inhibitors and TGFβ kinase inhibitors. Reduced Dach1 expression may define a subclass of PCa that warrants specific therapies.

Epithelial-to-Mesenchymal Transition-Related Markers in Prostate Cancer: From Bench to Bedside

Prostate cancer (PCa) is the second most frequent type of cancer in men worldwide, with 288,300 new cases and 34,700 deaths estimated in the United States in 2023. Treatment options for early-stage disease include external beam radiation therapy, brachytherapy, radical prostatectomy, active surveillance, or a combination of these. In advanced cases, androgen-deprivation therapy (ADT) is considered the first-line therapy; however, PCa in most patients eventually progresses to castration-resistant prostate cancer (CRPC) despite ADT. Nonetheless, the transition from androgen-dependent to androgen-independent tumors is not yet fully understood. The physiological processes of epithelial-to-non-epithelial ("mesenchymal") transition (EMT) and mesenchymal-to-epithelial transition (MET) are essential for normal embryonic development; however, they have also been linked to higher tumor grade, metastatic progression, and treatment resistance. Due to this association, EMT and MET have been identified as important targets for novel cancer therapies, including CRPC. Here, we discuss the transcriptional factors and signaling pathways involved in EMT, in addition to the diagnostic and prognostic biomarkers that have been identified in these processes. We also tackle the various studies that have been conducted from bench to bedside and the current landscape of EMT-targeted therapies.

State-of-the-art therapeutic strategies for targeting cancer stem cells in prostate cancer

The development of new therapeutic strategies is on the increase for prostate cancer stem cells, owing to current standardized therapies for prostate cancer, including chemotherapy, androgen deprivation therapy (ADT), radiotherapy, and surgery, often failing because of tumor relapse ability. Ultimately, tumor relapse develops into advanced castration-resistant prostate cancer (CRPC), which becomes an irreversible and systemic disease. Hence, early identification of the intracellular components and molecular networks that promote prostate cancer is crucial for disease management and therapeutic intervention. One of the potential therapeutic methods for aggressive prostate cancer is to target prostate cancer stem cells (PCSCs), which appear to be a primary focal point of cancer metastasis and recurrence and are resistant to standardized therapies. PCSCs have also been documented to play a major role in regulating tumorigenesis, sphere formation, and the metastasis ability of prostate cancer with their stemness features. Therefore, the current review highlights the origin and identification of PCSCs and their role in anti-androgen resistance, as well as stemness-related signaling pathways. In addition, the review focuses on the current advanced therapeutic strategies for targeting PCSCs that are helping to prevent prostate cancer initiation and progression, such as microRNAs (miRNAs), nanotechnology, chemotherapy, immunotherapy, the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) gene-editing system, and photothermal ablation (PTA) therapy.

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

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

Advances in Molecular Regulation of Prostate Cancer Cells by Top Natural Products of Malaysia

Prostate cancer (PCa) remains both a global health burden and a scientific challenge. We present a review of the molecular targets driving current drug discovery to fight this disease. Moreover, the preventable nature of most PCa cases represents an opportunity for phytochemicals as chemopreventive when adequately integrated into nutritional interventions. With a renovated interest in natural remedies as a commodity and their essential role in cancer drug discovery, Malaysia is looking towards capitalizing on its mega biodiversity, which includes the oldest rainforest in the world and an estimated 1200 medicinal plants. We here explore whether the list of top Malay plants prioritized by the Malaysian government may fulfill the potential of becoming newer, sustainable sources of prostate cancer chemotherapy. These include Andrographis paniculate, Centella asiatica, Clinacanthus nutans, Eurycoma longifolia, Ficus deltoidea, Hibiscus sabdariffa, Marantodes pumilum (syn. Labisia pumila), Morinda citrifolia, Orthosiphon aristatus, and Phyllanthus niruri. Our review highlights the importance of resistance factors such as Smac/DIABLO in cancer progression, the role of the CXCL12/CXCR4 axis in cancer metastasis, and the regulation of PCa cells by some promising terpenes (andrographolide, Asiatic acid, rosmarinic acid), flavonoids (isovitexin, gossypin, sinensetin), and alkylresorcinols (labisiaquinones) among others.

Bacterial RNA virus MS2 exposure increases the expression of cancer progression genes in the LNCaP prostate cancer cell line

Bacteriophages effectively counteract diverse bacterial infections, and their ability to treat most types of cancer has been explored using phage engineering or phage-virus hybrid platforms. In the present study, it was demonstrated that the bacteriophage MS2 can affect the expression of genes associated with the proliferation and survival of LNCaP prostate epithelial cells. LNCaP cells were exposed to bacteriophage MS2 at a concentration of 1×10⁷ plaque forming units/ml for 24-48 h. After exposure, various cellular parameters, including cell viability, morphology, and changes in gene expression, were examined. MS2 affected cell viability adversely, reducing viability by 25% in the first 4 h of treatment; however, cell viability recovered within 24-48 h. Similarly, the AKT, androgen receptor, integrin α5, integrin β1, MAPK1, MAPK3, STAT3, and peroxisome proliferator-activated receptor-γ coactivator 1α genes, which are involved in various normal cellular processes and tumor progression, were significantly upregulated, whereas the expression levels of HSP90, ITGB5, ITGB3, HSP27, ITGAV, and PI3K genes were unchanged. Therefore, based on viability and gene expression changes, bacteriophage MS2 severely impaired LNCaP cells by reducing anchorage-dependent survival and androgen signaling. A caveolin-mediated endocytosis mechanism for MS2-mediated signaling in prostate cancer cells was proposed based on reports involving bacteriophages T4, M13, and MS2, and their interactions with LNCaP and PC3 cell lines.

Physical Inactivity, Metabolic Syndrome and Prostate Cancer Diagnosis: Development of a Predicting Nomogram

Insufficient physical activity (PA) may be a shared risk factor for the development of both metabolic syndrome (MetS) and prostate cancer (PCa). To investigate this correlation and to develop a nomogram able to predict tumor diagnosis. Between 2016 and 2018, a consecutive series of men who underwent prostate biopsy at three institutions were prospectively enrolled. PA was self-assessed by patients through the Physical Activity Scale for the Elderly (PASE) questionnaire; MetS was assessed according to Adult Treatment Panel III criteria. A logistic regression analyses was used to identify predictors of PCa diagnosis and high-grade disease (defined as International Society of Uro-Pathology grade >2 tumors). A nomogram was then computed to estimate the risk of tumor diagnosis. A total of 291 patients were enrolled; 17.5% of them (n = 51) presented with MetS. PCa was diagnosed in 110 (38%) patients overall while 51 presented high-grade disease. At multivariable analysis, age (OR 1.04; 95%CI: 1.00−1.08; p = 0.048), prostate volume (PV) (OR 0.98; 95%CI: 0.79−0.99; p = 0.004), suspicious digital rectal examination (OR 2.35; 95%CI: 1.11−4.98; p = 0.02), total PSA value (OR 1.12; 95%CI: 1.05−1.2; p < 0.001), and PASE score (OR 0.99; 95%CI: 0.98−0.99; p = 0.01) were independent predictors of tumor diagnosis. The latter two also predicted high-grade PCa. MetS was not associated with PCa diagnosis and aggressiveness. The novel nomogram displayed fair discrimination for PCa diagnosis (AUC = 0.76), adequate calibration (p > 0.05) and provided a net benefit in the range of probabilities between 20% and 90%. reduced PA was associated with an increased risk of PCa diagnosis and high-grade disease. Our nomogram could improve the selection of patients scheduled for prostate biopsy at increased risk of PCa.

The CIC-ERF co-deletion underlies fusion-independent activation of ETS family member, ETV1, to drive prostate cancer progression

Human prostate cancer can result from chromosomal rearrangements that lead to aberrant ETS gene expression. The mechanisms that lead to fusion-independent ETS factor upregulation and prostate oncogenesis remain relatively unknown. Here, we show that two neighboring transcription factors, Capicua (CIC) and ETS2 repressor factor (ERF), which are co-deleted in human prostate tumors can drive prostate oncogenesis. Concurrent CIC and ERF loss commonly occur through focal genomic deletions at chromosome 19q13.2. Mechanistically, CIC and ERF co-bind the proximal regulatory element and mutually repress the ETS transcription factor, ETV1. Targeting ETV1 in CIC and ERF-deficient prostate cancer limits tumor growth. Thus, we have uncovered a fusion-independent mode of ETS transcriptional activation defined by concurrent loss of CIC and ERF.

Trabectedin (ET-743) in prostate cancer: Endoplasmic reticulum stress-induced apoptotic effect

Trabectedin is a chemotherapy agent originating from a tunicate, Ecteinascidia turbinata. In this study, DNA-independent action mechanisms of trabectedin are investigated in prostate cancer (PCa) cells. Cell viability was assessed via XTT assay. Apoptosis was evaluated via flow cytometry. Tetramethylrodamine ethyl ester (TMRE) dye was utilized to determine mitochondrial membrane potential (MMP). Cell cycle distribution was investigated via flow cytometric analysis. Reactive oxygen species (ROS) were monitored using fluorescence CM-H2DCFDA dye. Changes in CHOP, p-eIF2α, GRP78 and p-PERK which are endoplasmic reticulum (ER) stress-involved proteins were investigated via western blot. Trabectedin induced cytotoxicity and cell cycle arrest at the G2/M phase. Trabectedin decreased MMP via ROS generation in PCa cells. ER stress-related proteins CHOP, p-eIF2α, GRP78 and p-PERK were also elevated by trabectedin treatment indicating the induction of ER stress-induced apoptosis. The results of this study show that trabectedin may be an effective chemotherapeutic for PCa.

Combinatorial approaches of nanotherapeutics for inflammatory pathway targeted therapy of prostate cancer

Prostate cancer (PC) is the most prevalent male urogenital cancer worldwide. PC patients presenting an advanced or metastatic cancer succumb to the disease, even after therapeutic interventions including radiotherapy, surgery, androgen deprivation therapy (ADT), and chemotherapy. One of the hallmarks of PC is evading immune surveillance and chronic inflammation, which is a major challenge towards designing effective therapeutic formulations against PC. Chronic inflammation in PC is often characterized by tumor microenvironment alterations, epithelial-mesenchymal transition and extracellular matrix modifications. The inflammatory events are modulated by reactive nitrogen and oxygen species, inflammatory cytokines and chemokines. Major signaling pathways in PC includes androgen receptor, PI3K and NF-κB pathways and targeting these inter-linked pathways poses a major therapeutic challenge. Notably, many conventional treatments are clinically unsuccessful, due to lack of targetability and poor bioavailability of the therapeutics, untoward toxicity and multidrug resistance. The past decade witnessed an advancement of nanotechnology as an excellent therapeutic paradigm for PC therapy. Modern nanovectorization strategies such as stimuli-responsive and active PC targeting carriers offer controlled release patterns and superior anti-cancer effects. The current review initially describes the classification, inflammatory triggers and major inflammatory pathways of PC, various PC treatment strategies and their limitations. Subsequently, recent advancement in combinatorial nanotherapeutic approaches, which target PC inflammatory pathways, and the mechanism of action are discussed. Besides, the current clinical status and prospects of PC homing nanovectorization, and major challenges to be addressed towards the advancement PC therapy are also addressed.

Functional mechanism and clinical implications of miR-141 in human cancers

Cancer is caused by the abnormal proliferation of local tissue cells under the control of many oncogenic factors. MicroRNAs (miRNAs) are a class of evolutionarily conserved, approximately 22-nucleotide noncoding small RNAs that influence transcriptional regulationby binding to the 3'-untranslated region of target messenger RNA. As a member of the miRNA family, miR-141 acts as a suppressor or an oncomiR in various cancers and regulates cancer cell proliferation, apoptosis, invasion, and metastasis through a variety of signaling pathways, such as phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT) and constitutive activation of nuclear factor-κB (NF-κB). Target gene validation and pathway analysis have provided mechanistic insight into the role of this miRNA in different tissues. This review also outlines novel findings that suggest miR-141 may be useful as a noninvasive biomarker and as a therapeutic target in several cancers.

Multiplex immunohistochemical phenotyping of T cells in primary prostate cancer

BACKGROUND

Most prostate cancers are "immune cold" and poorly responsive to immune checkpoint inhibitors. However, the mechanisms responsible for the lack of a robust antitumor adaptive immune response in the prostate are poorly understood, which hinders the development of novel immunotherapeutic approaches.

AIMS

Most inflammatory infiltrates in the prostate are centered around benign glands and stroma, which can confound the molecular characterization of the antitumor immune response. We sought to analytically validate a chromogenic-based multiplex immunohistochemistry (IHC) approach applicable to whole slide digital image analysis to quantify T cell subsets from the tumor microenvironment of primary prostatic adenocarcinomas. As an initial application, we tested the hypothesis that PTEN loss leads to an altered antitumor immune response by comparing matched regions of tumors within the same individual with and without PTEN loss.

MATERIALS & METHODS

Using the HALO Image Analysis Platform (Indica Labs), we trained a classifier to quantify the densities of eight T cell phenotypes separately in the tumor epithelial and stromal subcompartments.

RESULTS

The iterative chromogenic approach using 7 different antibodies on the same slide provides highly similar findings to results using individually stained slides with single antibodies. Our main findings in carcinomas (benign removed) include the following: i) CD4+ T cells are present at higher density than CD8+ T cells; ii) all T cell subsets are present at higher densities in the stromal compartment compared to the epithelial tumor compartment; iii) most CD4+ and CD8+ T cells are PD1+; iv) cancer foci with PTEN loss harbored increased numbers of T cells compared to regions without PTEN loss, in both stromal and epithelial compartments; and v) the increases in T cells in PTEN loss regions were associated with ERG gene fusion status.

DISCUSSION

This modular approach can apply to any IHC-validated antibody combination and sets the groundwork for more detailed spatial analyses.

CONCLUSION

Iterative chromogenic IHC can be used for whole slide analysis of prostate tissue samples and can complement transcriptomic results including those using single cell and spatial genomic approaches.

Additional activation of the AR gene may be involved in the development of the castration resistance phenotype in prostate cancer

INTRODUCTION

Several studies have already shown that changes in the AR gene may be associated with a more aggressive disease phenotype and even castration-resistant prostate cancer. Thus, we investigated cytogenetic and molecular alterations linked to AR.

MATERIALS AND METHODS

To evaluate AR methylation, we performed a cytogenetic-molecular analysis using fluorescence in situ hybridization that uses specific probes for the AR gene (Xq11.12) and the X chromosome centromere. For AR activity, we performed a qualitative analysis of human androgen receptor activity. To analyze the expression of AR in PC3 and LNCaP cell lines, we used qPCR assays.

RESULTS

In the qPCR assay, we found downregulation of AR in the PC3 cell line compared with the LNCaP. We found the presence of X chromosome polysomy in PC-3 and LNCaP cell lines by FISH assay. In the HUMARA-Q assay, we found two X chromosomes/cell and the activity of both AR in the PC-3 cell line. In LNCaP cells, we found two X chromosomes/cell and methylation of only one AR.

CONCLUSION

Castration-resistant prostate cancer phenotype represents a significant challenge in the setting of urological management. The X chromosomes and AR-linked alterations may contribute to a better understanding of the disease. However, further studies should be performed in an attempt to elucidate as much as possible the role of AR in the castration-resistant prostate cancer phenotype.

Metabolic Syndrome and Physical Inactivity May Be Shared Etiological Agents of Prostate Cancer and Coronary Heart Diseases

Simple Summary

As metabolic syndrome (MetS) and a sedentary lifestyle are associated with an increased risk of prostate cancer (PCa) and cardiovascular diseases (CVDs), the 2 conditions may share common causes. We investigated the association between CVDs and PCa. Clinical data from patients undergone prostate biopsy were collected, physical activity (PA) was assessed and coronary heart diseases (CHDs) recorded. PCa was diagnosed in 395/955 men and 238 were aggressive tumors. Although CHDs were more common among PCa-patients (9.4% vs. 7.5%) the difference was not statistically significant and no difference was observed between low- and high-grade subgroups (9.5% vs. 9.2%). PA significantly reduced the risk of PCa diagnosis and aggressiveness while MetS only increased the risk of being diagnosed with cancer. CHDs were associated neither with tumor diagnosis nor aggressiveness. MetS and PA are strong predictors of PCa. We failed to prove a significant association between PCa and CHDs.

Abstract

As metabolic syndrome (MetS) and a sedentary lifestyle have been associated with an increased risk of developing both prostate cancer (PCa) and cardiovascular diseases (CVDs), the 2 conditions may share a common etiology. We aimed at investigating the association between CVDs and PCa. A retrospective analysis was performed. Our dataset on patients undergone systematic prostate biopsy was searched for histopathologic and clinical data. The physical activity (PA) scale for the elderly (PASE) was collected. Coronary heart diseases (CHDs) were recorded. Prognostic Grade Group ≥3 tumors were defined as high-grade (HG). The association between MetS, PA, CHDs and PCa was assessed using logistic regression analyses. Data on 955 patients were collected; 209 (22%) presented with MetS, 79 (8%) with CHDs. PCa was diagnosed in 395 (41.3%) men and 60% (n = 238) presented with an high-grade tumor. CHDs were more common among PCa-patients (9.4% vs. 7.5%; p = 0.302) but the difference was not statistically significant. No difference was observed between low- and high-grade subgroups (9.5% vs. 9.2%; p = 0.874). PASE independently predicted PCa diagnosis (OR: 0.287; p = 0.001) and HG-PCa (OR: 0.165; p = 0.001). MetS was an independent predictor of HG-PCa only (OR: 1.50; 95% CI: 1.100–2.560; p = 0.023). CHDs were not associated with tumor diagnosis and aggressiveness.

Health inequity drives disease biology to create disparities in prostate cancer outcomes

Prostate cancer exerts a greater toll on African American men than on White men of European descent (hereafter referred to as European American men): the disparity in incidence and mortality is greater than that of any other common cancer. The disproportionate impact of prostate cancer on Black men has been attributed to the genetics of African ancestry, to diet and lifestyle risk factors, and to unequal access to quality health care. In this Review, all of these influences are considered in the context of the evolving understanding that chronic or recurrent inflammatory processes drive prostatic carcinogenesis. Studies of inherited susceptibility highlight the contributions of genes involved in prostate cell and tissue repair (BRCA1/2, ATM) and regeneration (HOXB13 and MYC). Social determinants of health appear to accentuate these genetic influences by fueling prostate inflammation and associated cell and genome damage. Molecular characterization of the prostate cancers that arise in Black versus White men further implicates this inflammatory microenvironment in disease behavior. Yet, when Black and White men with similar grade and stage of prostate cancer are treated equally, they exhibit equivalent outcomes. The central role of prostate inflammation in prostate cancer development and progression augments the impact of the social determinants of health on disease pathogenesis. And, when coupled with poorer access to high-quality treatment, these inequities result in a disparate burden of prostate cancer on African American men.

What Do We Have to Know about PD-L1 Expression in Prostate Cancer? A Systematic Literature Review (Part 6): Correlation of PD-L1 Expression with the Status of Mismatch Repair System, BRCA, PTEN, and Other Genes

Pembrolizumab (anti-PD-1) is allowed in selected metastatic castration-resistant prostate cancer (PC) patients showing microsatellite instability/mismatch repair system deficiency (MSI-H/dMMR). BRCA1/2 loss-of-function is linked to hereditary PCs and homologous recombination DNA-repair system deficiency: poly-ADP-ribose-polymerase inhibitors can be administered to BRCA-mutated PC patients. Recently, docetaxel-refractory metastatic castration-resistant PC patients with BRCA1/2 or ATM somatic mutations had higher response rates to pembrolizumab. PTEN regulates cell cycle/proliferation/apoptosis through pathways including the AKT/mTOR, which upregulates PD-L1 expression in PC. Our systematic literature review (PRISMA guidelines) investigated the potential correlations between PD-L1 and MMR/MSI/BRCA/PTEN statuses in PC, discussing few other relevant genes. Excluding selection biases, 74/677 (11%) PCs showed dMMR/MSI; 8/67 (12%) of dMMR/MSI cases were PD-L1+. dMMR-PCs included ductal (3%) and acinar (14%) PCs (all cases tested for MSI were acinar-PCs). In total, 15/39 (39%) PCs harbored BRCA1/2 aberrations: limited data are available for PD-L1 expression in these patients. 13/137 (10%) PTEN- PCs were PD-L1+; 10/29 (35%) PD-L1+ PCs showed PTEN negativity. SPOP mutations may increase PD-L1 levels, while the potential correlation between PD-L1 and ERG expression in PC should be clarified. Further research should verify how the efficacy of PD-1 inhibitors in metastatic castration-resistant PCs is related to dMMR/MSI, DNA-damage repair genes defects, or PD-L1 expression.

Endocrine and paracrine characteristics of neuroendocrine prostate cancer

Prostate cancer is a common malignancy affecting men worldwide. While the vast majority of newly diagnosed prostate cancers are categorized as adenocarcinomas, a spectrum of uncommon tumor types occur including those with small cell and neuroendocrine cell features. Benign neuroendocrine cells exist in the normal prostate microenvironment, and these cells may give rise to primary neuroendocrine carcinomas. However, the more common development of neuroendocrine prostate cancer is observed after therapeutics designed to repress the signaling program regulated by the androgen receptor which is active in the majority of localized and metastatic adenocarcinomas. Neuroendocrine tumors are identified through immunohistochemical staining for common markers including chromogranin A/B, synaptophysin and neuron specific enolase (NSE). These markers are also common to neuroendocrine tumors that arise in other tissues and organs such as the gastrointestinal tract, pancreas, lung and skin. Notably, neuroendocrine prostate cancer shares biochemical features with nerve cells, particularly functions involving the secretion of a variety of peptides and proteins. These secreted factors have the potential to exert local paracrine effects, and distant endocrine effects that may modulate tumor progression, invasion, and resistance to therapy. This review discusses the spectrum of factors derived from neuroendocrine prostate cancers and their potential to influence the pathophysiology of localized and metastatic prostate cancer.

hsa_circ_0001275 Is One of a Number of circRNAs Dysregulated in Enzalutamide Resistant Prostate Cancer and Confers Enzalutamide Resistance In Vitro

Simple Summary

Although newer generations of androgen deprivation therapy such as enzalutamide are providing hope, it is clinically challenging to deliver effective therapy to individuals with metastatic castrate-resistant prostate cancer. Between 20–40% of patients have intrinsic resistance to therapy and all patients will ultimately experience disease progression due to acquired resistance, which is a significant clinical dilemma. The aim of our study was to evaluate the role of circular RNAs (circRNAs) in enzalutamide-resistant prostate cancer as part of the effort to identify useful biomarkers for patient selection and potential new therapeutic targets. We confirmed that hsa_circ_0001275 was highly upregulated in an enzalutamide resistant cell line and demonstrated that its overexpression resulted in increased enzalutamide resistance. Our data showed that hsa_circ_0001275 was not expressed abundantly in patient plasma samples, however, a trend of expression was evident which paralleled disease activity indicating a possible association with enzalutamide resistance. Overall, we have provided evidence that hsa_circ_0001275 promotes enzalutamide resistance and thus may serve as a potential therapeutic target.

Abstract

Background: Enzalutamide is part of the treatment regimen for metastatic castration-resistant prostate cancer (MCRPC). However, both intrinsic and acquired resistance to the drug remain substantial clinical quandaries. circRNAs, a novel type of non-coding RNA, have been identified in a number of cancers including prostate cancer and have been associated with cancer development and progression. circRNAs have shown great potential as clinically useful blood-based ‘liquid biopsies’ and as therapeutic targets in prostate cancer. The aim of this study was to examine the role of circRNA transcripts in enzalutamide-resistant prostate cancer cells and assess their utility as biomarkers. Methods: An isogenic cell line model of enzalutamide resistance was subjected to circRNA microarray profiling. Several differentially expressed circRNAs, along with their putative parental genes were validated using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). circRNAs of interest were stably overexpressed in the control cell line and drug sensitivity was assessed using an ELISA-based proliferation assay. The candidate circRNA, hsa_circ_0001275, was measured in patient plasma samples using RT-droplet digital PCR (RT-ddPCR). Results: hsa_circ_0001275 and its parental gene, PLCL2, were significantly up-regulated in strongly resistant clones vs. control (p < 0.05). Overexpression of hsa_circ_0001275 in the control cell line resulted in increased resistance to enzalutamide (p < 0.05). While RT-ddPCR analysis of hsa_circ_0001275 expression in plasma samples of 44 clinical trial participants showed a trend that mirrored the stages of disease activity (as defined by PSA level), the association did not reach statistical significance. Conclusions: Our data suggest that increased levels of hsa_circ_0001275 contribute to enzalutamide resistance. hsa_circ_0001275 plasma expression showed a trend that mirrors the PSA level at specific disease time points, indicating that circRNAs mirror disease recurrence and burden and may be associated with enzalutamide resistance.

Multifunctionality of prostatic acid phosphatase in prostate cancer pathogenesis

The role of human prostatic acid phosphatase (PAcP, P15309|PPAP_HUMAN) in prostate cancer was investigated using a new proteomics tool termed signal sequence swapping (replacement of domains from the native cleaved amino terminal signal sequence of secretory/membrane proteins with corresponding regions of functionally distinct signal sequence subtypes). This manipulation preferentially redirects proteins to different pathways of biogenesis at the endoplasmic reticulum (ER), magnifying normally difficult to detect subsets of the protein of interest. For PAcP, this technique reveals three forms identical in amino acid sequence but profoundly different in physiological functions, subcellular location, and biochemical properties. These three forms of PAcP can also occur with the wildtype PAcP signal sequence. Clinical specimens from patients with prostate cancer demonstrate that one form, termed ^PLPAcP, correlates with early prostate cancer. These findings confirm the analytical power of this method, implicate ^PLPAcP in prostate cancer pathogenesis, and suggest novel anticancer therapeutic strategies.

ARRDC4 and UBXN1: Novel Target Genes Correlated with Prostate Cancer Gleason Score

To investigate potential markers of the prostate cancer (PCa) Gleason score (GS), genetic arrays in 841 PCa patients were conducted followed by functional validation in PCa cell lines. A total of 841 PCa patients who received radical prostatectomy (RP) from November 2003 to July 2019 were enrolled. HumanExome BeadChip 12v1-1 (Illumina, Inc.; San Diego, CA, USA) exomic arrays were performed on RP tissue samples. Unconditional logistic regression was used to calculate odds ratios to generate estimates of the relative risk of pathologic GS (≥8); SNPs with the highest association were selected and validated using PCa cell lines (PC3, LNCaP, 22Rv1 and DU145). Following transfection with target-gene siRNA, assays for cell viability, wound healing, and transwell invasion were performed. Mean age of enrolled subjects was 66.34 years and median PSA was 8.43 ng/mL. After RP, 122 patients (14.5%) had pathological Gleason scores ≥8. The results from genotyping with 242,186 SNPs by exomic array revealed that 4 SNPs (rs200944490, rs117555780, rs34625170, and rs61754877) were significantly associated with high pathological GS (≥8) within cut-off level to p < 10^-5. The most highly associated rs200944490 in ARRDC4 (p = 1.39 × 10^-6) and rs117555780 in UBXN1 (p = 2.92 × 10^-5) were selected for further validation. The knockdown of UBXN1 and ARRDC4 led to significantly reduced cell proliferation and suppressed migration and invasiveness in PCa cell lines. Epithelial mesenchymal transition (EMT) markers were significantly down-regulated in si-ARRDC4 and si-UBXN1-transfected cells. The expression levels of PI3K-phosphorylation and Akt phosphorylation and NF-κB were also suppressed following knockdown of UBXN1 and ARRDC4. The rs200944490 (ARRDC4) and rs117555780 (UBXN1) were identified as candidate markers predictive of PCa Gleason score which is strongly associated with cancer aggressiveness. Additional validation in future studies is warranted.

Dietary polyphenol and microbiota interactions in the context of prostate health

Recent data strongly indicate a relationship between prostate health and gut microbiota, in which composition and physiological function strictly depend on dietary patterns. The bidirectional interplay of foods containing polyphenols, such as ellagitannins, condensed tannins, lignans, isoflavones, and prenylated flavonoids with human gut microbiota, has been proven to contribute to their impact on prostate health. Considering the attributed role of dietary polyphenols in the prevention of prostate diseases, this paper aims to critically review the studies concerning the influence of polyphenols' postbiotic metabolites on processes associated with the pathophysiology of prostate diseases. Clinical, in vivo, and in vitro studies on polyphenols have been juxtaposed with the current knowledge regarding their pharmacokinetics, microbial metabolism, and potential interactions with microbiota harboring different niches of the human organism. Directions of future research on dietary polyphenols regarding their interaction with microbiota and prostate health have been indicated.

METTL3-mediated m6A modification of KIF3C-mRNA promotes prostate cancer progression and is negatively regulated by miR-320d

The occurrence of distant metastasis is one of the leading causes of death in patients with prostate cancer (PCa). It is confirmed that kinesin protein is associated with a variety of malignancies, and the KIF3 family is related to cancer, but the relationship between KIF3C and prostate cancer is not clear. Our experiments have confirmed that KIF3C is highly expressed in prostate cancer tissues and cell lines. Further, functional tests have proven that KIF3C can promote the growth migration and invasion of PCa. We used Starbase 3.0 to discover that methyltransferase like 3 (METTL3) interacts with KIF3C. Our hypothesis and experiments concluded that METTL3 induced m6A modification on KIF3C, promoting the stabilization of KIF3C-mRNA by IGF2 binding protein 1 (IGF2BP1). The prediction that miR-320d inhibits KIF3C expression by targeting METTL3 using the miRmap website, was later confirmed experimentally. Further, a recovery experiment was used to confirm that miR-320d inhibited the progression of prostate cancer. KIF3C was overexpressed in prostate cancer, promoting its growth migration and invasion was induced by miR-320d/METTL3 in an m6A dependent process.

Bacteriophages M13 and T4 Increase the Expression of Anchorage-Dependent Survival Pathway Genes and Down Regulate Androgen Receptor Expression in LNCaP Prostate Cell Line

Wild-type or engineered bacteriophages have been reported as therapeutic agents in the treatment of several types of diseases, including cancer. They might be used either as naked phages or as carriers of antitumor molecules. Here, we evaluate the role of bacteriophages M13 and T4 in modulating the expression of genes related to cell adhesion, growth, and survival in the androgen-responsive LNCaP prostatic adenocarcinoma-derived epithelial cell line. LNCaP cells were exposed to either bacteriophage M13 or T4 at a concentration of 1 × 10⁵ pfu/mL, 1 × 10⁶ pfu/mL, and 1 × 10⁷ pfu/mL for 24, 48, and 72 h. After exposure, cells were processed for general morphology, cell viability assay, and gene expression analyses. Neither M13 nor T4 exposure altered cellular morphology, but both decreased the MTT reduction capacity of LNCaP cells at different times of treatment. In addition, genes AKT, ITGA5, ITGB1, ITGB3, ITGB5, MAPK3, and PI3K were significantly up-regulated, whilst the genes AR, HSPB1, ITGAV, and PGC1A were down-regulated. Our results show that bacteriophage M13 and T4 interact with LNCaP cells and effectively promote gene expression changes related to anchorage-dependent survival and androgen signaling. In conclusion, phage therapy may increase the response of PCa treatment with PI3K/AKT pathway inhibitors.

miR‑367‑3p downregulates Rab23 expression and inhibits Hedgehog signaling resulting in the inhibition of the proliferation, migration, and invasion of prostate cancer cells

MicroRNAs play an important role in tumor cell proliferation, invasion, and Rab23 is a member of the Ras-related small GTPase family and plays a critical role in the progression of may types of tumors. The present study was designed to investigate the inhibitory effect of microRNA (miR)-367-3p on the proliferation, invasion, and metastasis of prostate cancer cells. qRT-PCR was used to detect the expression of miR-367-3p in prostate cancer and adjacent tissues. Cell proliferation, scratch, and Transwell assays were performed to verify the inhibitory effect of miR-367-3p overexpression or Ras-related protein Rab 23 (Rab23) knockdown on prostate cancer. Double luciferase reporter assay was utilized to verify whether miR-367-3p could target the Rab23 3′-untranslated region (UTR). The expression levels of Rab23, Gli1, and Gli2 in prostate cancer cells transfected with the miR-367-3p mimic were detected via qRT-PCR analysis. miR-367-3p expression in the prostate cancer tissues was downregulated compared with that in the para-cancer control tissues. miR-367-3p expression in DU145 and PC3 cells was also downregulated compared with that in the human prostate epithelial cell line RWPE-1. The overexpression of miR-367-3p or the knockdown of Rab23 inhibited the proliferation, invasion, and metastasis of prostate cancer cells. The results of the luciferase reporter assay confirmed that Rab23 was a target gene that was regulated by miR-367-3p. miR-367-3p specifically bound to the 3′-UTR of Rab23 mRNA. The overexpression of miR-367-3p inhibited Rab23 expression and the Hedgehog pathway. Cell function experiments confirmed that the overexpression of Rab23 reversed the anticancer effect of miR-367-3p. miR-367-3p was able to inhibit the Hedgehog pathway by targeting the expression of the Rab23 gene, thus inhibiting the proliferation, invasion, and metastasis of prostate cancer cells.

A polymorphism in the promoter of FRAS1 is a candidate SNP associated with metastatic prostate cancer

BACKGROUND

Inflammation and one of its mediators, NF-kappa B (NFκB), have been implicated in prostate cancer carcinogenesis. We assessed whether germline polymorphisms associated with NFκB are associated with the risk of developing lethal disease (metastases or death from prostate cancer).

METHODS

Using a Bayesian approach leveraging NFκB biology with integration of publicly available datasets we used a previously defined genome-wide functional association network specific to NFκB and lethal prostate cancer. A dense-module-searching method identified modules enriched with significant genes from a genome-wide association study (GWAS) study in a discovery data set, Physicians' Health Study and Health Professionals Follow-up Study (PHS/HPFS). The top 48 candidate single nucleotide polymorphisms (SNPs) from the dense-module-searching method were then assessed in an independent prostate cancer cohort and the one SNP reproducibly associated with lethality was tested in a third cohort. Logistic regression models evaluated the association between each SNP and lethal prostate cancer. The candidate SNP was assessed for association with lethal prostate cancer in 6 of 28 studies in the prostate cancer association group to investigate cancer associated alterations in the genome (PRACTICAL) Consortium where there was some medical record review for death ascertainment which also had SNP data from the ONCOARRAY platform. All men self-identified as Caucasian.

RESULTS

The rs1910301 SNP which was reproducibly associated with lethal disease was nominally associated with lethal disease (odds ratio [OR] = 1.40; p = .02) in the discovery cohort and the minor allele was also associated with lethal disease in two independent cohorts (OR = 1.35; p = .04 and OR = 1.35; p = .07). Fixed effects meta-analysis of all three cohorts found an association: OR = 1.37 (95% confidence interval [CI]: 1.15-1.62, p = .0003). This SNP is in the promoter region of FRAS1, a gene involved in epidermal-basement membrane adhesion and is present at a higher frequency in men with African ancestry. No association was found in the subset of studies from the PRACTICAL consortium studies which had a total of 106 deaths out total of 3263 patients and a median follow-up of 4.4 years.

CONCLUSIONS

Through its connection with the NFκB pathway, a candidate SNP with a higher frequency in men of African ancestry without cancer was found to be associated with lethal prostate cancer across three well-annotated independent cohorts of Caucasian men.

Increased SPC24 in prostatic diseases and diagnostic value of SPC24 and its interacting partners in prostate cancer

SPC24 is a crucial component of the mitotic checkpoint machinery in tumorigenesis. High levels of SPC24 have been found in various cancers, including breast cancer, lung cancer, liver cancer, osteosarcoma and thyroid cancer. However, to the best of our knowledge, the impact of SPC24 on prostate cancer (PCa) and other prostate diseases remains unclear. In the present study expression of global SPC24 messenger RNA (mRNA) was assessed in a subset of patients with PCa included in The Cancer Genome Atlas (TCGA) database. Increased levels of SPC24 expression were found in PCa patients >60 years old compared to patients <60 and increased SPC24 expression was also associated with higher levels of prostate specific antigen (P<0.05) and lymph node metastasis (P<0.05). Higher levels of SPC24 expression were associated with negative outcomes in PCa patients (P<0.05). Furthermore, in Chinese patients with prostatitis, benign prostatic hypertrophy (BPH) and PCa, SPC24 was expressed at significantly higher levels than that in adjacent/normal tissues, as assessed by reverse transcription-quantitative polymerase chain reaction, immunohistochemistry and western blotting. High expression of SPC24 was associated with high Gleason stages (IV and V; P<0.05). Further analysis, based on Gene Ontology and pathway functional enrichment analysis, suggested that nuclear division cycle 80 (NDC80), an SPC24 protein interaction partner, and mitotic spindle checkpoint serine/threonine-protein kinase BUB1 (BUB1), a core subunit of the spindle assembly checkpoint, may be associated with SPC24 in PCa development. Finally, using binary logistic regression, algorithms combining the receiver operating characteristic between SPC24 and BUB1 or NDC80 indicated that a combination of these markers may provide better PCa diagnosis ability than other PCa diagnosis markers. Taken together, these findings suggest that SPC24 may be a promising prostate disease biomarker.

Progress in gene therapy treatments for prostate cancer

Prostate cancer is one of the predominant cancers affecting men and has been widely reported. In the past, various therapies and drugs have been proposed to treat prostate cancer. Among these treatments, gene therapy has been considered to be an optimal and widely applicable treatment. Furthermore, due to the increased specificity of gene sequence complementation, the targeted delivery of complementary gene sequences may represent a useful treatment in certain instances. Various gene therapies, including tumor-suppressor gene therapy, suicide gene therapy, immunomodulation gene therapy and anti-oncogene therapies, have been established to treat a wide range of diseases, such as cardiac disease, cystic fibrosis, HIV/AIDS, diabetes, hemophilia, and cancers. To this end, several gene therapy clinical trials at various phases are underway. This overview describes the developments and progress in gene therapy, with a special focus being placed on prostate cancer.

NKX3.1 Localization to Mitochondria Suppresses Prostate Cancer Initiation

Mitochondria provide the first line of defense against the tumor-promoting effects of oxidative stress. Here we show that the prostate-specific homeoprotein NKX3.1 suppresses prostate cancer initiation by protecting mitochondria from oxidative stress. Integrating analyses of genetically engineered mouse models, human prostate cancer cells, and human prostate cancer organotypic cultures, we find that, in response to oxidative stress, NKX3.1 is imported to mitochondria via the chaperone protein HSPA9, where it regulates transcription of mitochondrial-encoded electron transport chain (ETC) genes, thereby restoring oxidative phosphorylation and preventing cancer initiation. Germline polymorphisms of NKX3.1 associated with increased cancer risk fail to protect from oxidative stress or suppress tumorigenicity. Low expression levels of NKX3.1 combined with low expression of mitochondrial ETC genes are associated with adverse clinical outcome, whereas high levels of mitochondrial NKX3.1 protein are associated with favorable outcome. This work reveals an extranuclear role for NKX3.1 in suppression of prostate cancer by protecting mitochondrial function. SIGNIFICANCE: Our findings uncover a nonnuclear function for NKX3.1 that is a key mechanism for suppression of prostate cancer. Analyses of the expression levels and subcellular localization of NKX3.1 in patients at risk of cancer progression may improve risk assessment in a precision prevention paradigm, particularly for men undergoing active surveillance.See related commentary by Finch and Baena, p. 2132.This article is highlighted in the In This Issue feature, p. 2113.

INPP4B protects from metabolic syndrome and associated disorders

A high fat diet and obesity have been linked to the development of metabolic dysfunction and the promotion of multiple cancers. The causative cellular signals are multifactorial and not yet completely understood. In this report, we show that Inositol Polyphosphate-4-Phosphatase Type II B (INPP4B) signaling protects mice from diet-induced metabolic dysfunction. INPP4B suppresses AKT and PKC signaling in the liver thereby improving insulin sensitivity. INPP4B loss results in the proteolytic cleavage and activation of a key regulator in de novo lipogenesis and lipid storage, SREBP1. In mice fed with the high fat diet, SREBP1 increases expression and activity of PPARG and other lipogenic pathways, leading to obesity and non-alcoholic fatty liver disease (NAFLD). Inpp4b-/- male mice have reduced energy expenditure and respiratory exchange ratio leading to increased adiposity and insulin resistance. When treated with high fat diet, Inpp4b-/- males develop type II diabetes and inflammation of adipose tissue and prostate. In turn, inflammation drives the development of high-grade prostatic intraepithelial neoplasia (PIN). Thus, INPP4B plays a crucial role in maintenance of overall metabolic health and protects from prostate neoplasms associated with metabolic dysfunction.

Dietary Factors and Prostate Cancer Development, Progression, and Reduction

Due to the constantly increasing number of cases, prostate cancer has become one of the most important health problems of modern societies. This review presents the current knowledge regarding the role of nutrients and foodstuff consumption in the etiology and development of prostate malignancies, including the potential mechanisms of action. The results of several in vivo and in vitro laboratory experiments as well as those reported by the clinical and epidemiological research studies carried out around the world were analyzed. The outcomes of these studies clearly show the influence of both nutrients and food products on the etiology and prevention of prostate cancer. Consumption of certain nutrients (saturated and trans fatty acids) and food products (e.g., processed meat products) leads to the disruption of prostate hormonal regulation, induction of oxidative stress and inflammation, and alteration of growth factor signaling and lipid metabolism, which all contribute to prostate carcinogenesis. On the other hand, a high consumption of vegetables, fruits, fish, and whole grain products exerts protective and/or therapeutic effects. Special bioactive functions are assigned to compounds such as flavonoids, stilbenes, and lycopene. Since the influence of nutrients and dietary pattern is a modifiable risk factor in the development and prevention of prostate cancer, awareness of the beneficial and harmful effects of individual food ingredients is of great importance in the global strategy against prostate cancer.

Genomic and phenotypic heterogeneity in prostate cancer

From a clinical, morphological and molecular perspective, prostate cancer is a heterogeneous disease. Primary prostate cancers are often multifocal, having topographically and morphologically distinct tumour foci. Sequencing studies have revealed that individual tumour foci can arise as clonally distinct lesions with no shared driver gene alterations. This finding demonstrates that multiple genomically and phenotypically distinct primary prostate cancers can be present in an individual patient. Lethal metastatic prostate cancer seems to arise from a single clone in the primary tumour but can exhibit subclonal heterogeneity at the genomic, epigenetic and phenotypic levels. Collectively, this complex heterogeneous constellation of molecular alterations poses obstacles for the diagnosis and treatment of prostate cancer. However, advances in our understanding of intra-tumoural heterogeneity and the development of novel technologies will allow us to navigate these challenges, refine approaches for translational research and ultimately improve patient care.

Biological Aspects of Cancer Health Disparities

Racial and ethnic disparities span the continuum of cancer care and are driven by a complex interplay among social, psychosocial, lifestyle, environmental, health system, and biological determinants of health. Research is needed to identify these determinants of cancer health disparities and to develop interventions to achieve cancer health equity. Herein, we focus on the overall burden of ancestry-related molecular alterations, the functional significance of the alterations in hallmarks of cancer, and the implications of the alterations for precision oncology and immuno-oncology. In conclusion, we reflect on the importance of estimating ancestry, improving diverse racial and ethnic participation in cancer clinical trials, and examining the intersection among determinants of cancer health disparities.

Monocyte counts and prostate cancer outcomes in white and black men: results from the SEARCH database

PURPOSE

Circulating inflammatory markers may predict prostate cancer (PC) outcomes. For example, a recent study showed that higher peripheral blood monocyte counts were associated with aggressive PC in Asian men undergoing radical prostatectomy (RP). Herein, we investigated whether peripheral monocyte count can predict long-term PC outcomes after RP in black and white men.

METHODS

We retrospectively reviewed data on 2345 men undergoing RP from 2000 to 2017 at eight Veterans Affairs hospitals. Data on monocyte count within 6 and 12 months prior to surgery were collected. The study outcomes were biochemical recurrence (BCR), castration-resistant PC (CRPC), metastasis, all-cause mortality (ACM), and PC-specific morality (PCSM). Cox-proportional hazard models were used to assess the associations between pre-operative monocyte count and the above-mentioned outcomes accounting for confounders.

RESULTS

Of 2345 RP patients, 972 (41%) were black and 1373 (59%) were white men. In multivariable analyses, we found no associations between monocyte count and BCR among all men (HR: 1.36, 95%CI 0.90-2.07) or when analyses were stratified by race (HR: 1.30, 95%CI 0.69-2.46, in black men; HR:1.33, 95%CI 0.76-02.33, in white men). Likewise, no overall or race-specific associations were found between monocyte count and CRPC, metastases, ACM, and PCSM, all p ≥ 0.15. Results were similar for monocyte count measured at 12 months prior to RP.

CONCLUSION

In black and white PC patients undergoing RP, peripheral monocyte count was not associated with long-term PC outcomes. Contrary to what was found in Asian populations, monocyte count was not associated with PC outcomes in this study.

[EFFECT OF NEW ANDROGEN RECEPTOR AXIS-TARGETED AGENTS ON SURVIVAL OF CASTRATION-RESISTANT PROSTATE CANCER]

(Background)The real world's effect of new androgen receptor axis-targeted agents (ARATs) on survival of castration-resistant prostate cancer (CRPC) remains unclear in Japan. (Aims)The primary aim was to determine the clinical benefit of ARATs on survival of CRPC patients. The secondary aim was to evaluate predictive factors affecting the survival of CRPC patients. (Patients and results)Among 236 patients treated with androgen deprivation therapy (ADT), 68 patients developed CRPC; two groups of 34 patients were treated with ARATs (A cases) or conventional ADT (V cases). In a median follow-up of 61.5 months, 20 A and 22 V cases died of cancer. Median survival time (MST) from diagnosis was 99 and 66 months for A and V cases, respectively, and MST from CRPC to death were 50.5 and 44.5 months, respectively. There were no significant differences between both cases. The hazard ratio for death from diagnosis or CRPC progression of the A cases to V cases was 0.711; 95% confidence interval (CI), 0.371 to 1.362; P = 0.3037, or 0.805; 95% CI, 0.434 to 1.491; P=0.4899, respectively. Multivariable analysis revealed that a unique and significant independent prognostic factor from diagnosis was time to CRPC. (Conclusions)In this small retrospective study, we could not determine the clinical benefit of new ARATs compared with conventional ADT on survival of CRPC patients, and a unique and significant independent prognostic factor from diagnosis was time to CRPC. We need to validate these results in a future multi-institutional study.

Microbes in Tumoral In Situ Tissues and in Tumorigenesis

Cancerous tumors are severe diseases affecting human health that have a complicated etiology and pathogenesis. Microbes have been considered to be related to the development and progression of numerous tumors through various pathogenic mechanisms in recent studies. Bacteria, which have so far remained the most studied microbes worldwide, have four major possible special pathogenic mechanisms (modulation of inflammation, immunity, DNA damage, and metabolism) that are related to carcinogenesis. This review aims to macroscopically summarize and verify the relationships between microbes and tumoral in situ tissues from cancers of four major different systems (urinary, respiratory, digestive, and reproductive); the abovementioned four microbial pathogenic mechanisms, as well as some synergistic pathogenic mechanisms, are also discussed. Once the etiologic role of microbes and their precise pathogenic mechanisms in carcinogenesis are known, the early prevention, diagnosis, and treatment of cancers would progress significantly.