Benign Prostatic Hyperplasia Samples Research Articles

MiR-1202 regulates BPH-1 cell proliferation, apoptosis, and epithelial-to-mesenchymal transition through targeting HMGCL.

Benign prostatic hyperplasia (BPH) is the expansion of the prostate gland that results in urinary symptoms. Both the epithelial-to-mesenchymal transition (EMT) and the Wnt signaling pathway are associated with BPH pathology. In this study, we find that miR-1202 is increased in BPH samples. Overexpression of miR-1202 in TGF-β-treated BPH-1 cells enhances cell survival and DNA synthesis and inhibits cell apoptosis, whereas miR-1202 inhibition partially abolishes the effects of TGF-β on BPH-1 cells. miR-1202 overexpression reduces E-cadherin level but elevates vimentin, N-cadherin, and snail levels, whereas miR-1202 inhibition partially attenuates the effects of TGF-β on EMT markers. Regarding the Wnt/β-catenin pathway, miR-1202 overexpression significantly enhances, whereas miR-1202 inhibition partially decreases, the promotive effects of TGF-β on Wnt1, c-Myc, and cyclin D1 proteins. 3-Hydroxy-3-methylglutaryl-CoA lyase (HMGCL) is a direct downstream target of miR-1202, and miR-1202 inhibits HMGCL expression through binding to its 3'UTR. Overexpression of HMGCL significantly reduces the effect of miR-1202 overexpression on the phenotypes of BPH-1 cells by inhibiting cell survival and promoting apoptosis. Similarly, HMGCL overexpression has the opposite effects on EMT markers and the Wnt/β-catenin signaling, and markedly alleviates the effects of miR-1202 overexpression. Finally, in the BPH rat model, Ki67 and vimentin levels are elevated, but E-cadherin and HMGCL levels are reduced. In conclusion, miR-1202 is upregulated in benign prostatic hyperplasia; miR-1202 enhances epithelial cell proliferation, suppresses cell apoptosis, and promotes EMT by targeting HMGCL. The Wnt/β-catenin pathway may participate in the miR-1202/HMGCL axis-mediated regulation of BPH-1 cell phenotypes.

Abstract 1839: Proteomic and glycoproteomic differences associated with prostate cancer in urine

Abstract Background and Aims: Prostate cancer is one of the most common cancers affecting men in the United States, with ~288,300 new cases and 34,700 deaths in 2023 alone. Prostate-specific antigen (PSA), the most widely used prostate cancer biomarker, lacks specificity and sensitivity, leading to unnecessary biopsies, overdiagnosis, and overtreatment. There is an urgent unmet clinical need to find new biomarkers that can distinguish patients with benign disease from those with prostate cancer. Urine is an attractive source for these biomarkers as prostate-derived proteins are more highly concentrated in urine than in blood. To better understand both global proteomic and glycoproteomic molecular signatures that could lead to improved diagnostics for prostate cancer, we analyzed urine samples from unaffected men, men with benign prostatic hyperplasia (BPH), and men with prostate cancer. Methods: Urine samples (N = 58 total) were collected from unaffected men (N = 17), men with BPH (N = 24), and men with prostate cancer (N = 17). Samples were digested with trypsin and analyzed with high-resolution liquid chromatography-tandem mass spectrometry (LC-MS/MS) for shotgun proteomics analysis. Association with cancer was determined through supervised analysis using Pearson correlation. For glycoproteomics analysis, intact glycopeptides were enriched using strong anion exchange-electrostatic repulsion hydrophilic interaction chromatography, fractionated using high pH reversed-phase chromatography, and analyzed with LC-MS/MS. Association with the three conditions was determined through several rounds of supervised analysis using Pearson correlation. Results: In total, 3542 human proteins were identified, and 78 proteins (p < 0.01) were significantly associated with prostate cancer. The glycolysis pathway and lysosome pathway were enriched in samples from men with prostate cancer. In the glycoproteomics analysis, 36 proteins (p < 0.05) had altered glycan diversity in one of the three conditions, and the complement and coagulation cascade pathway and the lysosome pathway were highly enriched. Six proteins (p < 0.05) had significantly increased glycan diversity in the cancerous samples than in the BPH and normal samples. Conclusions: This study identifies a set of interesting proteomic and glycoproteomic differences in urine from men with prostate cancer compared to BPH and non-cancer samples, which warrant further investigation in additional sample cohorts as potential novel biomarkers. Citation Format: Nikhiya Shamsher, Fernando Garcia-Marques, Abel Bermudez, Mark R. Flory, Sharon J. Pitteri. Proteomic and glycoproteomic differences associated with prostate cancer in urine [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1839.

PRL-mediated STAT5B/ARRB2 pathway promotes the progression of prostate cancer through the activation of MAPK signaling

Previous study showed that higher expression of prolactin (PRL) was found in CRPC samples compared with hormone-naive prostate cancer (HNPC) and benign prostatic hyperplasia (BPH) samples. We further investigate the function of PRL in prostate cancer (PCa) and explored its downstream effects. We found heterogeneous expression of the PRLR in clinical prostate samples. The VCaP and 22Rv1 cells exhibited PRLR expression. Among the downstream proteins, STAT5B was the dominant subtype in clinical samples and cell lines. Human recombinant PRL stimulation of PCa cells with PRLR expression resulted in increased phosphorylation of STAT5B(pSTAT5B) and progression of PCa in vitro and in vivo, and STAT5B knockdown can suppress the malignant behavior of PCa. To understand the mechanism further, we performed Bioinformatic analysis, ChIP qPCR, and luciferase reporter gene assay. The results revealed that ARRB2 was the transcription target gene of STAT5B, and higher expression of ARRB2 was related to higher aggression and poorer prognosis of PCa. Additionally, Gene set enrichment analysis indicated that higher expression of ARRB2 was significantly enriched in the MAPK signaling pathway. Immunohistochemistry (IHC) demonstrated elevated pSTAT5B, ARRB2, and pERK1/2 expression levels in CRPC tissues compared to HNPC and BPH. Mechanically, ARRB2 enhanced the activation of the MAPK pathway by binding to ERK1/2, thereby promoting the phosphorylation of ERK1/2 (pERK1/2). In conclusion, our study demonstrated that PRL stimulation can promote the progression of PCa through STAT5B/ARRB2 pathway and activation of MAPK signaling, which can be suppressed by intervention targeting STAT5B. Blockade of the STAT5B can be a potential therapeutic target for PCa.

Whole-exome sequencing of Nigerian benign prostatic hyperplasia reveals increased alterations in apoptotic pathways.

Through whole-exome sequencing of 60 formalin-fixed paraffin-embedded Nigerian (NGRn) benign prostatic hyperplasia (BPH) samples, we identified germline and somatic alterations in apoptotic pathways impacting BPH development and progression. Prostate enlargement is a common occurrence in male aging; however, this enlargement can lead to lower urinary tract symptoms that negatively impact quality of life. This impact is disproportionately present in men of African ancestry. BPH pathophysiology is poorly understood and studies examining non-European populations are lacking. In this study, NGRn BPH, normal prostate, and prostate cancer (PCa) tumor samples were sequenced and compared to characterize genetic alterations in NGRn BPH. Two hundred and two nonbenign, ClinVar-annotated germline variants were present in NGRn BPH samples. Six genes [BRCA1 (92%), HSD3B1 (85%), TP53 (37%), PMS2 (23%), BARD1 (20%), and BRCA2 (17%)] were altered in at least 10% of samples; however, compared to NGRn normal and tumor, the frequency of alterations in BPH samples showed no significant differences at the gene or variant level. BRCA2_rs11571831 and TP53_rs1042522 germline alterations had a statistically significant co-occurrence interaction in BPH samples. In at least two BPH samples, 173 genes harbored somatic variants known to be clinically actionable. Three genes (COL18A1, KIF16B, and LRP1) showed a statistically significant (p < 0.05) higher frequency in BPH. NGRn BPH also had five gene pairs (PKD1/KIAA0100, PKHD1/PKD1, DNAH9/LRP1B, NWD1/DCHS2, and TCERG1/LMTK2) with statistically significant co-occurring interactions. Two hundred and seventy-nine genes contained novel somatic variants in NGRn BPH. Three genes (CABP1, FKBP1C, and RP11-595B24.2) had a statistically significant (p < 0.05) higher alteration frequency in NGRn BPH and three were significantly higher in NGRn tumor (CACNA1A, DMKN, and CACNA2D2). Pairwise Fisher's exact tests showed 14 gene pairs with statistically significant (p < 0.05) interactions and four interactions approaching significance (p < 0.10). Mutational patterns in NGRn BPH were similar to COSMIC (Catalog of Somatic Mutations in Cancer) signatures associated with aging and dysfunctional DNA damage repair. NGRn BPH contained significant germline alteration interactions (BRCA2_rs11571831 and TP53_rs1042522) and increased somatic alteration frequencies (LMTK2, LRP1, COL18A1, CABP1, and FKBP1C) that impact apoptosis. Normal prostate development is maintained by balancing apoptotic and proliferative activity. Dysfunction in either mechanism can lead to abnormal prostate growth. This work is the first to examine genomic sequencing in NGRn BPH and provides data that fill known gaps in the understanding BPH and how it impacts men of African ancestry.

Transcriptomic analysis of benign prostatic hyperplasia identifies critical pathways in prostatic overgrowth and 5-alpha reductase inhibitor resistance.

The medical therapy of prostatic symptoms (MTOPS) trial randomized men with symptoms of benign prostatic hyperplasia (BPH) and followed response of treatment with a 5α-reductase inhibitor (5ARI), an alpha-adrenergic receptor antagonist (α-blocker), the combination of 5ARI and α-blocker or no medical therapy (none). Medical therapy reduced risk of clinical progression by 66% but the reasons for nonresponse or loss of therapeutic response in some patients remains unresolved. Our previous work showed that prostatic glucocorticoid levels are increased in 5ARI-treated patients and that glucocorticoids can increased branching of prostate epithelia in vitro. To understand the transcriptomic changes associated with 5ARI treatment, we performed bulk RNA sequencing of BPH and control samples from patients who received 5ARI versus those that did not. Deconvolution analysis was performed to estimate cellular composition. Bulk RNA sequencing was also performed on control versus glucocorticoid-treated prostate epithelia in 3D culture to determine underlying transcriptomic changes associated with branching morphogenesis. Surgical BPH (S-BPH) tissue was defined as benign prostatic tissue collected from the transition zone (TZ) of patients who failed medical therapy while control tissue termed Incidental BPH (I-BPH) was obtained from the TZ of men undergoing radical prostatectomy for low-volume/grade prostatic adenocarcinoma confined to the peripheral zone. S-BPH patients were divided into four subgroups: men on no medical therapy (none: n = 7), α-blocker alone (n = 10), 5ARI alone (n = 6) or combination therapy (α-blocker and 5ARI: n = 7). Control I-BPH tissue was from men on no medical therapy (none: n = 8) or on α-blocker (n = 6). A human prostatic cell line in 3D culture that buds and branches was used to identify genes involved in early prostatic growth. Snap-frozen prostatic tissue taken at the time of surgery and 3D organoids were used for RNA-seq analysis. Bulk RNAseq data were deconvoluted using CIBERSORTx. Differentially expressed genes (DEG) that were statistically significant among S-BPH, I-BPH, and during budding and branching of organoids were used for pathway analysis. Transcriptomic analysis between S-BPH (n = 30) and I-BPH (n = 14) using a twofold cutoff (p < 0.05) identified 377 DEG (termed BPH377) and a cutoff < 0.05 identified 3377 DEG (termed BPH3377). Within the S-BPH, the subgroups none and α-blocker were compared to patients on 5ARI to reveal 361 DEG (termed 5ARI361) that were significantly changed. Deconvolution analysis of bulk RNA seq data with a human prostate single cell data set demonstrated increased levels of mast cells, NK cells, interstitial fibroblasts, and prostate luminal cells in S-BPH versus I-BPH. Glucocorticoid (GC)-induced budding and branching of benign prostatic cells in 3D culture was compared to control organoids to identify early events in prostatic morphogenesis. GC induced 369 DEG (termed GC359) in 3D culture. STRING analysis divided the large datasets into 20-80 genes centered around a hub. In general, biological processes induced in BPH supported growth and differentiation such as chromatin modification and DNA repair, transcription, cytoskeleton, mitochondrial electron transport, ubiquitination, protein folding, and cholesterol synthesis. Identified signaling pathways were pooled to create a list of DEG that fell into seven hubs/clusters. The hub gene centrality was used to name the network including AP-1, interleukin (IL)-6, NOTCH1 and NOTCH3, NEO1, IL-13, and HDAC/KDM. All hubs showed connections to inflammation, chromatin structure, and development. The same approach was applied to 5ARI361 giving multiple networks, but the EGF and sonic hedgehog (SHH) hub was of particular interest as a developmental pathway. The BPH3377, 5ARI363, and GC359 lists were compared and 67 significantly changed DEG were identified. Common genes to the 3D culture included an IL-6 hub that connected to genes identified in BPH hubs that defined AP1, IL-6, NOTCH, NEO1, IL-13, and HDAC/KDM. Reduction analysis of BPH and 3D organoid culture uncovered networks previously identified in prostatic development as being reinitiated in BPH. Identification of these pathways provides insight into the failure of medical therapy for BPH and new therapeutic targets for BPH/LUTS.

Spatial architectures of somatic mutations in normal prostate, benign prostatic hyperplasia and coexisting prostate cancer

This study aimed to identify somatic mutations in nontumor cells (NSMs) in normal prostate and benign prostatic hyperplasia (BPH) and to determine their relatedness to prostate cancer (PCA). From 22 PCA patients, two prostates were sampled for 3-dimensional mapping (50 normal, 46 BPH and 1 PCA samples), and 20 prostates were trio-sampled (two normal or BPH samples and one PCA sample) and analyzed by whole-genome sequencing. Normal and BPH tissues harbored several driver NSMs and copy number alterations (CNAs), including in FOXA1, but the variations exhibited low incidence, rare recurrence, and rare overlap with PCAs. CNAs, structural variants, and mutation signatures were similar between normal and BPH samples, while BPHs harbored a higher mutation burden, shorter telomere length, larger clone size, and more private NSMs than normal prostates. We identified peripheral-zonal dominance and right-side asymmetry in NSMs, but the asymmetry was heterogeneous between samples. In one normal prostate, private oncogenic RAS-signaling NSMs were detected, suggesting convergence in clonal maintenance. Early embryonic mutations exhibited two distinct distributions, characterized as layered and mixed patterns. Our study identified that the BPH genome differed from the normal prostate genome but was still closer to the normal genome than to the PCA genome, suggesting that BPH might be more related to aging or environmental stress than to tumorigenic processes.

Human papillomavirus and prostate cancer: systematic review and meta-analysis

The involvement of human papillomavirus (HPV) in the prostate carcinogenesis is a controversial issue. The presented meta-analysis was carried out to systematize the currently available research results regarding this question. The meta-analysis includes case–control studies from 1991 to 2022, which were collected from publicly available bibliometric databases. The meta-analysis was performed using Meta-Essentials_1.5 software. We used Begg’s and Egger’s methods to assess publication bias. Cochran’s Q test was used to assess heterogeneity and the I2 index was employed for calculating the variation in the pooled estimations. The analysis was based on data from 27 case–control studies, which in total yielded 1607 tumour tissue samples of prostate and 1515 control samples (317 samples of normal tissue, 1198 samples of benign prostatic hyperplasia (BPH)). According to the data obtained, there was high risk of prostate cancer by HPV infection in both cases. HPV was found in prostate cancer in 25.8% of cases, while in normal tissue samples the virus was detected in 9.2% of cases and in 17.4% with BPH as a control. In particular, more studies on the association of HPV and prostate cancer are needed to prove the role of HPV in the development of prostate cancer. In addition to the controversial question of whether HPV infection is associated with prostate cancer risk, it is worth considering whether the samples used as a control have an impact on the results. The impact of HPV in prostate tumour tissue samples on outcome should also be investigated.

Cocaine and amphetamine regulated transcript (CART): a newly characterized neuropeptide in human prostate

ABSTRACT Cocaine and amphetamine regulated transcript (CART) is a somatostatin-like polypeptide. CART has been localized in the CNS, hypothalamo-pituitary-adrenocortical (HPA) axis, pancreatic islets and enteric nervous system. We investigated the cellular localization of CART in normal human prostate, benign prostatic hyperplasia, prostatic intraepithelial neoplasia and acinar adenocarcinoma. CART was assessed using immunohistochemistry (IHC) and in situ hybridization (ISH), and its gene expression was identified by RTqPCR. We found cellular expression of CART in both normal prostatic luminal secretory epithelial cells neuroendocrine cells (NEC) of both ducts and acini. The cellular appearance indicated a cycle of neuropeptide synthesis and secretion as validated by ISH/IHC concordance. RTqPCR analysis also validated the immunohistochemical data and gene expression, which both indicated low to moderate expression in prostatic tissues. CART expression also was increased in both neuroendocrine and glandular epithelial cell populations from samples of benign prostatic hyperplasia as validated by IHC, ISH and RTqPCR. CART expression was markedly diminished and, in some cases, entirely absent in tissues of prostatic intraepithelial neoplasia and adenocarcinoma. Owing to loss of CART expression in adenocarcinoma and its increase in benign prostatic hyperplasia, CART may prove to be an important prostate marker.

Integrative analysis of the ST6GALNAC family identifies GATA2-upregulated ST6GALNAC5 as an adverse prognostic biomarker promoting prostate cancer cell invasion

BackgroundST6GALNAC family members function as sialyltransferases and have been implicated in cancer progression. However, their aberrant expression levels, prognostic values and specific roles in metastatic prostate cancer (PCa) remain largely unclear.MethodsTwo independent public datasets (TCGA-PRAD and GSE21032), containing 648 PCa samples in total, were employed to comprehensively examine the mRNA expression changes of ST6GALNAC family members in PCa, as well as their associations with clinicopathological parameters and prognosis. The dysregulation of ST6GALNAC5 was further validated in a mouse PCa model and human PCa samples from our cohort (n = 64) by immunohistochemistry (IHC). Gene Set Enrichment Analysis, Gene Ontology, Kyoto Encyclopedia of Genes and Genomes and drug sensitivity analyses were performed to enrich the biological processes most related to ST6GALNAC5. Sulforhodamine B, transwell, luciferase reporter and chromatin immunoprecipitation (ChIP) assays were used to examine the PCa cell proliferation, invasion and transcriptional regulation, respectively.ResultsSystematical investigation of six ST6GALNAC family members in public datasets revealed that ST6GALNAC5 was the only gene consistently and significantly upregulated in metastatic PCa, and ST6GALNAC5 overexpression was also positively associated with Gleason score and predicted poor prognosis in PCa patients. IHC results showed that (1) ST6GALNAC5 protein expression was increased in prostatic intraepithelial neoplasia and further elevated in PCa from a PbCre;PtenF/F mouse model; (2) overexpressed ST6GALNAC5 protein was confirmed in human PCa samples comparing with benign prostatic hyperplasia samples from our cohort (p < 0.001); (3) ST6GALNAC5 overexpression was significantly correlated with perineural invasion of PCa. Moreover, we first found transcription factor GATA2 positively and directly regulated ST6GALNAC5 expression at transcriptional level. ST6GALNAC5 overexpression could partially reverse GATA2-depletion-induced inhibition of PCa cell invasion. The GATA2-ST6GALNAC5 signature exhibited better prediction on the poor prognosis in PCa patients than GATA2 or ST6GALNAC5 alone.ConclusionsOur results indicated that GATA2-upregulated ST6GALNAC5 might serve as an adverse prognostic biomarker promoting prostate cancer cell invasion.

Phenotype and Reactivity of Lymphocytes Expanded from Benign Prostate Hyperplasic Tissues and Prostate Cancer.

Benign prostate hyperplasia (BPH) is a frequent condition in aging men, which affects life quality, causing principally lower urinary tract symptoms. Epidemiologic studies suggest that BPH may raise the risk of developing prostate cancer (PCa), most likely promoting a chronic inflammatory environment. Studies aiming at elucidating the link and risk factors that connect BPH and PCa are urgently needed to develop prevention strategies. The BPH microenvironment, similar to the PCa one, increases immune infiltration of the prostate, but, in contrast to PCa, immunosuppression may not be established yet. In this study, we found that prostate-infiltrating lymphocytes (PILs) expanded from hyperplastic prostate tissue recognized tumor-associated antigens (TAA) and autologous tissue, regardless of the presence of tumor cells. PILs expanded from BPH samples of patients with PCa, however, seem to respond more strongly to autologous tissue. Phenotypic characterization of the infiltrating PILs revealed a trend towards better expanding CD4+ T cells in infiltrates derived from PCa, but no significant differences were found. These findings suggest that T cell tolerance is compromised in BPH-affected prostates, likely due to qualitative or quantitative alterations of the antigenic landscape. Our data support the hypothesis that BPH increases the risk of PCa and may pave the way for new personalized preventive vaccine strategies for these patients.

Fabrication of Antibody Conjugated Super Magnetic Oxide Nanoparticles for Early Detection of Prostate Cancer.

Prostate cancer is one of the most widespread cancers in the world. Early diagnosis is the most important factor in treatment efficiency. Furthermore, new methods for early diagnosis and treatment play an important role. In this study, we designed targeted conjugation of antibodies with iron nanoparticles and evaluated the binding properties of antibodies to prostate cancers and benign tissues. This method in addition to having a lower cost has high sensitivity and specificity. Anti- PSCA antibodies were purified and conjugated to super magnetic oxide nanoparticles (SPION). Then, iron staining on prostate adenocarcinoma tissues was performed. At the same time, immunohistochemically staining was performed on similar tissues to compare the results. In addition, benign prostatic hyperplasia (BPH) samples were used as a control sample. In adenocarcinoma tissues with iron staining, many blue spots are seen compared to benign tissues, and the number of these spots increases with increasing tumor grade. These findings indicate the characteristic of iron staining as a conjugate antibody to iron can be an appropriate approach to specific staining of tumor markers in cancer tissues and can be used to diagnose prostate cancer due to its safety, low cost, sensitivity, and specificity.

MicroRNA 138 upregulation is associated with decreasing levels of CCND1 gene expression and promoting cell death in human prostate cancer cell lines

This research intended to discover the significance of miR-138 on the espression profile, proliferation, and the associated regulatory mechanisms in prostate cancer (PCa). RT-qPCR was applied to compare the expression of miR-138 in the PCa cells with a non-cancer cell line, as well as PCa tissue samples with benign prostatic hyperplasia (BPH) samples. The expression of miR-138 notably diminished in PCa tissues and cell lines. Afterward, formerly documented genes, along with bioinformatics analysis, suggested seven possible target genes of miR-138. Among them, CCND1 seemed to have higher expression in the PCa cell lines and tissues. Also, the negative correlation of miR-138 and CCND1 in PCa cell line and tissues was validated using Pearson correlation. CCDN1 was revealed to be the target gene of miR138 in the PC3 cell line based on the results of the luciferase reporter gene assay. Over-expression of miR138-5p suppressed the expression of CCDN1 in PCa cell lines as exhibited by RT-qPCR. Finally, the results of the MTT assay exhibited the inhibitory impact of miR-138 on the proliferative capacities in PCa cell lines. Our research introduces miR-138 as a negative regulator of CCDN1 in the progression of PCa with an inhibitory impact on the proliferation rate of prostate cancer (PCa) cell lines. This regulatory mechanism could be utilized for the design and target selection of remedial miRNA-based approaches.

A prognostic signature consisting of N6-methyladenosine modified mRNAs demonstrates clinical potential in prediction of biochemical recurrence and guidance on precision therapy in prostate cancer

Novel biomarkers are urgently needed to improve the prediction of clinical outcomes and guide personalized treatment for prostate cancer (PCa) patients. However, the role of N6-methyladenosine (m6A) modifications in PCa initiation and progression remains largely elusive. In our study, we collected benign Prostate Hyperplasia (BPH), localized PCa, and metastatic PCa samples from patients and performed methylated RNA immunoprecipitation sequencing (MeRIP-Seq) to map m6A-methylated mRNAs. Furthermore, we developed a prognostic signature based on 239 differentially methylated RNAs and the TCGA-PRAD dataset, which can be used to calculate an m6A-modified mRNA (MMM) score for a PCa patient, validated by independent multi-center cohorts. Our findings revealed that differential m6A modifications were positively correlated with altered expressions of mapped m6A-modified mRNAs. Higher MMM scores were associated with shorter times to biochemical recurrence (BCR) in PCa patients, and the MMM scoring system outperformed three well-established signatures in nine independent validation cohorts, as demonstrated by Kaplan-Meier survival analysis, C-index and ROC. Patients who did not respond to androgen receptor signaling inhibitor (ARSI) therapy and immunotherapy were found to have high MMM scores. Two hub genes, TLE1 and PFKL, were confirmed to have m6A sites through MeRIP-qPCR, and their knockdown promoted PCa cell invasion. Bioinformatics analysis of single-cell databases identified cell types with high transcript abundance levels of these two genes. In summary, our study is the first to perform transcriptome-wide m6A mapping in prostate tissues. The translational potential of a prognostic signature, comprising m6A-methylated mRNAs, in predicting clinical outcomes and therapy responses for PCa patients, is demonstrated.

Abstract 4720: Chromatin conformation alterations in prostate cancer progression and formation of castration resistance

Abstract Introduction: Prostate cancer (PC) is the most common cancer in men and second in cancer related deaths. Aggressive prostate cancer is typically treated with androgen depletion therapy which often results in the formation of castration resistant prostate cancer (CRPC). Androgen receptor (AR) is a transcription factor that regulates hundreds of target genes and is responsible for the differentiation and function of normal prostate epithelial cells. In addition to AR, multiple other TFs that bind to distal enhancers have been implicated in PC, such as FOXA1, MYC and HOXB13. Understanding the role of these distal regulators is paramount in PC. Methods: To study the changes in chromatin conformation in prostate cancer progression, we have sequenced clinical benign prostatic hyperplasia (BPH), PC and CRPC samples using Hi-C sequencing. From each group 6 samples were sequenced with a total of 18 samples in the cohort. In addition, we have combined a multi omics cohort consisting of chromatin accessibility, transcriptome and methylome sequencing data from matching samples. Together these data types allow us to map out the regulatory networks in PC and CRPC by probing the distal active regulatory sites and their interactions. To account for artifacts caused by genomic aberrations in cancer samples we have established a pipeline for normalizing these effects in HiC-data. Results: Overall topologically associated domains (TADs) and A/B-compartments remain stable between the groups. However, local changes of compartments in loci of key genes, such as AKR1C3 and FOXA1 correlate with their gene expression. We detect differential loops between sample groups and these changes are associated with gene expression alterations in PCs. Distal enhancers of PC up-regulated genes are enriched for FOXA1 and HOXB13. Interestingly, up-regulated loops in CRPC are enriched for FOXA1 and HOXB13, while no systematic effect on gene expression is seen on a genome wide scale, apart from genes such as AR and CENPE whose expression correlates strongly with their association to distal enhancers. We also detect enhancer hijacking events in driver genes. One example is the recurrent ETV1-MIPOL1 fusion, where promoter of ETV1 forms contacts with FOXA1 enhancer regions. Conclusions: Alterations in loop structures are strongly associated with regulatory programs that have been previously implicated in PC, including regulation by FOXA1, HOXB13 and other transcription factors. This highlights the importance of chromatin conformation in facilitating the effects of regulatory programs that rely on distal enhancers in PC. These changes appear more systematic in untreated PCs, whilst CRPCs exhibit more heterogeneity in chromatin conformation across the samples. Citation Format: Tuomo Virtanen, Ebrahim Afyounian, Riikka Nurminen, Teuvo Tammela, Tapio Visakorpi, Juha Kesseli, Kirsi Rautajoki, Matti Nykter. Chromatin conformation alterations in prostate cancer progression and formation of castration resistance. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4720.

Commentary on "Integrative multiplatform molecular profiling of benign prostatic hyperplasia identifies distinct subtypes".

Commentary on "Integrative multiplatform molecular profiling of benign prostatic hyperplasia identifies distinct subtypes".

Human BKV large T genome detection in prostate cancer and benign prostatic hyperplasia tissue samples by nested PCR: A case-control study.

Human BK polyomavirus (BKPyV) is a latent infectious agent in the genitourinary tract associated with hemorrhagic cystitis and nephropathy. This virus can be a risk factor for various human malignancies, including prostate cancer (PCa). It may contribute to prostate cancer development, as it demonstrates oncogenic properties by encoding oncoproteins. This study assessed the prevalence of this virus in benign and malignant prostate tissues. Between 2009 and 2019, 49 formalin-fixed paraffin-embedded (FFPE) PCa and 49 benign prostatic hyperplasia (BPH) samples were gathered from the pathology department of a tertiary care university hospital. They were used as cases and controls, respectively. After deparaffinization and DNA extraction, nested PCR was applied to identify the BKPyVgp5 gene (LTAg) using inner and outer primers. The nested PCR showed a 278-bp bond corresponding to the BKPyVgp5 genome (LTAg) in 53.1% (26/49) of PCa and 14.3% (7/49) of BPH (p<0.001). The presence of BKV was significantly associated with an increased risk of PCa development (OR=6.78, 95% CI=2.55-18.02, p<0.001). The BKV LTAg gene was significantly more prevalent in PCa samples than in BPH samples. These results demonstrate the presence of the virus in prostate cancer tissues.

POLYAMINES AS NEW POTENTIAL BIOMARKERS FORDIFFERENTIAL DIAGNOSIS OF PROSTATE CANCER ANDESTIMATION OF ITS AGGRESSIVENESS.

Prostate cancer (PCa) is one of the most common malignancies in older men. The study of tissue markers of PCa can provide information about the state of proliferation and apoptosis in tumors, the susceptibility of tumor cells to metastasis and the mechanisms of resistance to therapy, which, in turn, can help predict the course of the disease and develop personalized treatment. Polyamines (PAs) spermine, spermidine, putrescine are of particular interest in terms of PCa tissue markers. To investigate the levels of basic and acetylated forms of PAs in the postoperative samples of malignant and benign tumors of the human prostate and evaluate the possibility of their use for differential diagnosis and assessment of the PCa aggressiveness. 57postoperative tumor samples from patients with prostate adenocarcinoma of different Gleason score (GS) and clinical stage (T1-T4) and 20samples of tumors from patients with benign prostate hyperplasia (BPH) were studied. The content of PAs was determined by high performance liquid chromatography. Among the studied PAs, the most significant difference between PCa and BPH was observed for spermine (Spm). The level of Spm in PCa samples was 16times lower than in BPH samples (p<0.01). We did not find a significant dependence of PAs levels, including Spm, on the clinical stage. The association between the Spm level and the GS was established. The indolent (GS6) tumors were characterized by the highest Spm level while in the most aggressive (GS9and GS10) tumors Spm content was the lowest. A sharp decrease in Spm levels is probably a characteristic feature of prostate malignant tumors. The obtained results indicate an association of Spm levels in tumors with the GS. This may indicate Spm involvement in the formation of the aggressiveness of PCa. The results of the study can be further used for differential diagnosis of prostate tumors and for assessing the aggressiveness of PCa.

The architecture of clonal expansions in morphologically normal tissue from cancerous and non-cancerous prostates

BackgroundUp to 80% of cases of prostate cancer present with multifocal independent tumour lesions leading to the concept of a field effect present in the normal prostate predisposing to cancer development. In the present study we applied Whole Genome DNA Sequencing (WGS) to a group of morphologically normal tissue (n = 51), including benign prostatic hyperplasia (BPH) and non-BPH samples, from men with and men without prostate cancer. We assess whether the observed genetic changes in morphologically normal tissue are linked to the development of cancer in the prostate.ResultsSingle nucleotide variants (P = 7.0 × 10–03, Wilcoxon rank sum test) and small insertions and deletions (indels, P = 8.7 × 10–06) were significantly higher in morphologically normal samples, including BPH, from men with prostate cancer compared to those without. The presence of subclonal expansions under selective pressure, supported by a high level of mutations, were significantly associated with samples from men with prostate cancer (P = 0.035, Fisher exact test). The clonal cell fraction of normal clones was always higher than the proportion of the prostate estimated as epithelial (P = 5.94 × 10–05, paired Wilcoxon signed rank test) which, along with analysis of primary fibroblasts prepared from BPH specimens, suggests a stromal origin. Constructed phylogenies revealed lineages associated with benign tissue that were completely distinct from adjacent tumour clones, but a common lineage between BPH and non-BPH morphologically normal tissues was often observed. Compared to tumours, normal samples have significantly less single nucleotide variants (P = 3.72 × 10–09, paired Wilcoxon signed rank test), have very few rearrangements and a complete lack of copy number alterations.ConclusionsCells within regions of morphologically normal tissue (both BPH and non-BPH) can expand under selective pressure by mechanisms that are distinct from those occurring in adjacent cancer, but that are allied to the presence of cancer. Expansions, which are probably stromal in origin, are characterised by lack of recurrent driver mutations, by almost complete absence of structural variants/copy number alterations, and mutational processes similar to malignant tissue. Our findings have implications for treatment (focal therapy) and early detection approaches.

METTL3 promotes prostatic hyperplasia by regulating PTEN expression in an m6A-YTHDF2-dependent manner

Uncontrolled epithelial cell proliferation in the prostate transition zone and the hyper-accumulation of mesenchymal-like cells derived from the epithelial-mesenchymal transition (EMT) of prostatic epithelium are two key processes in benign prostatic hyperplasia (BPH). m6A RNA modification affects multiple cellular processes, including cell proliferation, apoptosis, and differentiation. In this study, the aberrant up-regulation of methylase METTL3 in BPH samples suggests its potential role in BPH development. Elevated m6A modification in the prostate of the BPH rat was partially reduced by METTL3 knockdown. METTL3 knockdown also partially reduced the prostatic epithelial thickness and prostate weight, significantly improved the histological features of the prostate, inhibited epithelial proliferation and EMT, and promoted apoptosis. In vitro, METTL3 knockdown decreased TGF-β-stimulated BPH-1 cell proliferation, m6A modification, and EMT, whereas promoted cell apoptosis. METTL3 increased the m6A modification of PTEN and inhibited its expression through the reading protein YTHDF2. PTEN knockdown aggravated the molecular, cellular, and pathological alterations in the prostate of BPH rats and amplified TGF-β-induced changes in BPH-1 cells. More importantly, PTEN knockdown partially abolished the improving effects of METTL3 knockdown both in vivo and in vitro. In conclusion, the level of m6A modification is elevated in BPH; the METTL3/YTHDF2/PTEN axis disturbs the balance between epithelial proliferation and apoptosis, promotes EMT, and accelerates BPH development in an m6A modification-related manner.

Differential Microbial Signature Associated With Benign Prostatic Hyperplasia and Prostate Cancer.

Apart from other risk factors, chronic inflammation is also associated with the onset of Prostate Cancer (PCa), wherein pathogen infection and tissue microbiome dysbiosis are known to play a major role in both inflammatory response and cancer development. However, except for a few studies, the link between microbes and PCa remained poorly understood. To explore the potential microbiome signature associated with PCa in Indian patients, we investigated differential compositions of commensal bacteria among patients with benign prostatic hyperplasia (BPH) and PCa using 16S rRNA amplicon sequencing followed by qPCR analyses using two distinct primer sets. Using two independent cohorts, we show that Prevotella copri, Cupriavidus campinensis, and Propionibacterium acnes represent the three most abundant bacteria in diseased prostate lesions. LEfSe analyses identified that while Cupriavidus taiwanensis and Methylobacterium organophilum are distinctly elevated in PCa samples, Kocuria palustris and Cellvibrio mixtus are significantly enriched in BPH samples. Furthermore, we identify that a number of human tumor viruses, including Epstein-Barr virus (EBV) and hepatitis B virus (HBV), along with two high-risk human papillomaviruses - HPV-16 and HPV-18, are significantly associated with the PCa development and strongly correlated with PCa bacterial signature. The study may thus offer to develop a framework for exploiting this microbial signature for early diagnosis and prognosis of PCa development.