Genetics and biology of prostate cancer

Alteration of the HIF-1α/VEGF Signaling Pathway and Disruption of the Cell Cycle by Second Generation Carbosilan Dendrimers

Current therapies against prostate cancer (PCa) disease, such as surgery, radiotherapy, or in last term chemical castration by androgen deprivation, have led to significant reduction of the incidence of PCa throughout the world. Worse prognosis is found in those patients which exhibit castration resistance, relapsing into the disease with even greater aggressiveness. Hypoxia cancer cell adaption has been observed to be closely connected to fatal prognostic tumor features. Therefore, hypoxia adaptive mechanisms of cancer cells have attracted large interest as a relevant biological target for treatment-resistant patients. Dendrimers have been established as a promising nanotechnological tool owing to their beneficial physicochemical features such as multivalency and monodispersity. Herein, we have completed a thorough study to better understand the effect within the cell of the already published ruthenium(II)-N-heterocyclic carbene metallodendrimer (G₂Ru) that was able to drastically reduce HIF-1α stabilization and exhibited antiproliferative capability against androgen-sensitive (LNCaP) and androgen-resistant prostate cancer cells (LNFLU) in vitro. G₂Ru, as well as its cationic imidazolium precursor (G₂P), displayed scavenging properties against intracellular and externally stimulated ROS levels, which would presumably hinder the stabilization of HIF-1α by prolyl hydroxylase (PHD) inhibition. Furthermore, these dendrimers have shown considerably beneficial properties against tumor progression capability in terms of apoptosis, cell cycle, CSCs expression, and epithelial phenotype promotion. Taken all together, in this study we could demonstrate the extraordinary anticancer properties of NHC-based carbosilane dendrimers against androgen-resistant prostate cancer cells in vitro.

The LINC00852/miR-29a-3p/JARID2 axis regulates the proliferation and invasion of prostate cancer cell

Long intergenic non-coding RNA 00852 (LINC00852) has been shown to promote the progression of many different cancers including prostate cancer. However, the involved mechanism in promoting the proliferation, migration and invasion of prostate cancer cells has not been reported. In this study, we found that LINC00852 was highly expressed in the tissue of prostate cancer using quantitative reverse transcription PCR (qRT-PCR). CCK-8 assay, colony formation experiment, Transwell migration and invasion experiments were performed to prove that the up-regulation of LINC00852 could promote the proliferation, migration and invasion of prostate cancer cells in vitro. Xenograft tumors experiments in nude mice confirmed that up-regulation of LINC00852 promoted the proliferation of prostate cancer cells in vivo. Bioinformatics predictions and dual-luciferase reporter gene assay showed that miR-29a-3p binds to the 3'-untranslated region of JARID2, and the enhancement of miR-29a-3p could reverse the effect of LINC00852 overexpression in vitro. Moreover, the results of qRT-PCR and western blot showed that LINC00852 could regulate the expression of JARID2 through miR-29a-3p induction. In summary, we demonstrated that LINC00852 played a key role in promoting the prostate cancer, and LINC00852/miR-29a-3p/JARID2 axis could be used as a target for prostate cancer treatment.

Liquid Biopsy in Diagnosis and Prognosis of Non-Metastatic Prostate Cancer

Currently, sensitive and specific methods for the detection and prognosis of early stage PCa are lacking. To establish the diagnosis and further identify an appropriate treatment strategy, prostate specific antigen (PSA) blood test followed by tissue biopsy have to be performed. The combination of tests is justified by the lack of a highly sensitive, specific, and safe single test. Tissue biopsy is specific but invasive and may have severe side effects, and therefore is inappropriate for screening of the disease. At the same time, the PSA blood test, which is conventionally used for PCa screening, has low specificity and may be elevated in the case of noncancerous prostate tumors and inflammatory conditions, including benign prostatic hyperplasia and prostatitis. Thus, diverse techniques of liquid biopsy have been investigated to supplement or replace the existing tests of prostate cancer early diagnosis and prognostics. Here, we provide a review on the advances in diagnosis and prognostics of non-metastatic prostate cancer by means of various biomarkers extracted via liquid biopsy, including circulating tumor cells, exosomal miRNAs, and circulating DNAs.

The DNA/RNA helicase DHX9 contributes to the transcriptional program of the androgen receptor in prostate cancer

Background

Prostate cancer (PC) is the most commonly diagnosed male malignancy and an important cause of mortality. Androgen deprivation therapy is the first line treatment but, unfortunately, a large part of patients evolves to a castration-resistant stage, for which no effective cure is currently available. The DNA/RNA helicase DHX9 is emerging as an important regulator of cellular processes that are often deregulated in cancer.

Methods

To investigate whether DHX9 modulates PC cell transcriptome we performed RNA-sequencing analyses upon DHX9 silencing in the androgen-responsive cell line LNCaP. Bioinformatics and functional analyses were carried out to elucidate the mechanism of gene expression regulation by DHX9. Data from The Cancer Genome Atlas were mined to evaluate the potential role of DHX9 in PC.

Results

We found that up-regulation of DHX9 correlates with advanced stage and is associated with poor prognosis of PC patients. High-throughput RNA-sequencing analysis revealed that depletion of DHX9 in androgen-sensitive LNCaP cells affects expression of hundreds of genes, which significantly overlap with known targets of the Androgen Receptor (AR). Notably, AR binds to the DHX9 promoter and induces its expression, while Enzalutamide-mediated inhibition of AR activity represses DHX9 expression. Moreover, DHX9 interacts with AR in LNCaP cells and its depletion significantly reduced the recruitment of AR to the promoter region of target genes and the ability of AR to promote their expression in response to 5α-dihydrotestosterone. Consistently, silencing of DXH9 negatively affected androgen-induced PC cell proliferation and migration.

Conclusions

Collectively, our data uncover a new role of DHX9 in the control of the AR transcriptional program and establish the existence of an oncogenic DHX9/AR axis, which may represent a new druggable target to counteract PC progression.

A lncRNA-immune checkpoint-related gene signature predicts metastasis-free survival in prostate adenocarcinoma

Background

The 5-year overall survival rate in metastatic prostate adenocarcinoma (PRAD) is extremely low. Genomic studies of PRAD have improved our understanding of disease biology. However, the role of immune checkpoint genes (ICGs) in PRAD remains unclear.

Methods

Univariate and multivariate analyses were used to analyze genes associated with metastasis-free survival (MFS) in The Cancer Genome Atlas (TCGA)-PRAD dataset. The expressions of ADORA2A and TNFRSF18 were detected via immunohistochemical assay and real-time fluorescence quantitative PCR (RT-PCR) assay in our in-house cohort. The expression of long non-coding RNAs (lncRNAs) AL139287.1, SLC9A3-AS1, and SNHG12 were detected via RT-PCR assay in our in-house cohort. Stepwise regression, Cox regression, and nomogram analyses were used to evaluate the prognostic role of these genes in both the TCGA dataset and in-house cohort. The "pRRophetic" R package was used to evaluate drug sensitivity in the TCGA cohort according to the gene mRNA expression level.

Results

In our study, univariate and multivariate analyses revealed that the mRNA expressions of two ICGs, ADORA2A and TNFRSF18, were independent factors affecting MFS in PRAD patients. A prognostic 2-ICG model predicted the MFS of PRAD patients with medium-to-high accuracy in the TCGA dataset and in-house cohort. The expressions of AL139287.1, SLC9A3-AS1, and SNHG12 were correlated with ADORA2A and TNFRSF18. A prognostic lncRNA-ICG model predicted the MFS of PRAD patients with medium-to-high accuracy in the TCGA dataset and in-house cohort. In addition, correlation analyses between the sensitivity of doxorubicin, erlotinib, gemcitabine, or vinorelbine and AL139287.1, SLC9A3-AS1, SNHG12, ADORA2A, and TNFRSF18 were conducted.

Conclusions

Our results provide new targets for predicting tumor metastasis in PRAD and treating patients with metastatic PRAD.

The toxicity mechanism of glabridin in prostate cancer cells is involved in reactive oxygen species-dependent PI3K/Akt pathway: Integrated utilization of bioinformatic analysis and in vitro test validation

Glabridin is a prenylated isoflavonoid with considerable anticancer property. Reactive oxygen species (ROS) have evolved as regulators of many cellular signaling pathways in prostate cancer (PC). However, the role of ROS signaling in the anticancer activity of glabridin has not been investigated. Here, we attempted to evaluate the effect of glabridin on PC and the involvement of ROS signaling. Intracellular ROS and mitochondrial ROS (mitoROS) production in PC cell lines, DU-145 and LNCaP, were measured by H2DCFDA and MitoSOX Red staining, respectively. MTT assay was used to analyze the cellular viability. EdU staining assay was conducted to analyze the cell proliferation. To analyze apoptotic rate, TUNEL assay was performed. Caspase-3 activity was detected to reflect cell apoptosis. Western blot was carried out to detect the expression levels of Akt and p-Akt. We found that intracellular ROS and mitoROS levels were dose-dependently upregulated after glabridin treatment in both DU-145 and LNCaP cells, which was reversed by the treatment of ROS inhibitor, N-acetyl-L-cysteine (NAC). Glabridin inhibited the cell viability and reduced the number of EdU-positive DU-145 and LNCaP cells, which were respectively proved by MTT assay and EdU staining assay. Glabridin promoted cell death with increased apoptotic rate and caspase-3 activity in DU-145 and LNCaP cells. The effects of glabridin on cell proliferation and apoptosis were reversed by NAC. Moreover, glabridin suppressed the ratio of p-Akt/Akt, while NAC mitigated the decreased p-Akt/Akt ratio. In addition, the effects of glabridin on cell proliferation and apoptosis were also attenuated by Akt activator, SC79. Collectively, our results demonstrated that glabridin suppressed proliferation and induced apoptosis in PC cells via regulating ROS-mediated PI3K/Akt pathway. These findings suggested that glabridin might hold a promising prospective as a therapeutic agent against PC.

Understanding the Dual Roles of CircHIPK3 in Tumorigenesis and Tumor Progression

CircHIPK3 is a type of endogenous circular RNA, which contains a covalently closed circular structure and cannot encode protein or polypeptide. CircHIPK3 is unusually expressed in varieties of tumors and plays dual roles of tumor promotion or tumor inhibition in tumorigenesis and development of tumors by serving as the sponge for miRNA in multiple tumors. Here, we reviewed the differential expression, the dual functions, the regulation mechanism, and the network in a variety of tumors as well as the potential value for the diagnosis and treatment of tumors, which are of great significance for our comprehensive understanding of the roles and mechanisms of circHIPK3 in tumors.

The Clinical, Diagnostic, Therapeutic, and Prognostic Characteristics of Brain Metastases in Prostate Cancer: A Systematic Review

AIM

Prostate cancer (PCa) is the second most common nonskin malignancy and the second most common cause of cancer-related deaths in men. The most common site of metastasis in PCa is the axial skeleton which may lead to back pain or pathological fractures. Hematogenous spread to the brain and involvement of the central nervous system (CNS) are a rare occurrence. However, failed androgen deprivation therapy (ADT) may facilitate such a spread resulting in an advanced metastatic stage of PCa, which carries a poor prognosis.

METHODS

In this systematic review, we searched the PubMed, Scopus, and Web of Science online databases based on the PRISMA guideline and used all the medical subject headings (MeSH) in terms of the following search line: ("Brain Neoplasms" OR "Central Nervous System Neoplasms") and ("Prostatic Neoplasms" OR "Prostate"). Related studies were identified and reviewed.

RESULTS

A total of 59 eligible studies (902 patients) were included in this systematic review. In order to gain a deeper understanding, we extracted and presented the data from included articles based on clinical manifestations, diagnostic methods, therapeutic approaches, and prognostic status of PCa patients having BMs.

CONCLUSION

We have demonstrated the current knowledge regarding the mechanism, clinical manifestations, diagnostic methods, therapeutic approaches, and prognosis of BMs in PCa. These data shed more light on the way to help clinicians and physicians to understand, diagnose, and manage BMs in PCa patients better.

ARID1A loss induces polymorphonuclear myeloid-derived suppressor cell chemotaxis and promotes prostate cancer progression

Chronic inflammation and an immunosuppressive microenvironment promote prostate cancer (PCa) progression and diminish the response to immune checkpoint blockade (ICB) therapies. However, it remains unclear how and to what extent these two events are coordinated. Here, we show that ARID1A, a subunit of the SWI/SNF chromatin remodeling complex, functions downstream of inflammation-induced IKKβ activation to shape the immunosuppressive tumor microenvironment (TME). Prostate-specific deletion of Arid1a cooperates with Pten loss to accelerate prostate tumorigenesis. We identify polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) as the major infiltrating immune cell type that causes immune evasion and reveal that neutralization of PMN-MDSCs restricts the progression of Arid1a-deficient tumors. Mechanistically, inflammatory cues activate IKKβ to phosphorylate ARID1A, leading to its degradation via β-TRCP. ARID1A downregulation in turn silences the enhancer of A20 deubiquitinase, a critical negative regulator of NF-κB signaling, and thereby unleashes CXCR2 ligand-mediated MDSC chemotaxis. Importantly, our results support the therapeutic strategy of anti-NF-κB antibody or targeting CXCR2 combined with ICB for advanced PCa. Together, our findings highlight that the IKKβ/ARID1A/NF-κB feedback axis integrates inflammation and immunosuppression to promote PCa progression.

Grace-AKO: a novel and stable knockoff filter for variable selection incorporating gene network structures

Motivation

Variable selection is a common statistical approach to identifying genes associated with clinical outcomes of scientific interest. There are thousands of genes in genomic studies, while only a limited number of individual samples are available. Therefore, it is important to develop a method to identify genes associated with outcomes of interest that can control finite-sample false discovery rate (FDR) in high-dimensional data settings.

Results

This article proposes a novel method named Grace-AKO for graph-constrained estimation (Grace), which incorporates aggregation of multiple knockoffs (AKO) with the network-constrained penalty. Grace-AKO can control FDR in finite-sample settings and improve model stability simultaneously. Simulation studies show that Grace-AKO has better performance in finite-sample FDR control than the original Grace model. We apply Grace-AKO to the prostate cancer data in The Cancer Genome Atlas program by incorporating prostate-specific antigen (PSA) pathways in the Kyoto Encyclopedia of Genes and Genomes as the prior information. Grace-AKO finally identifies 47 candidate genes associated with PSA level, and more than 75% of the detected genes can be validated.

Integrated analysis to identify the AC005154.6/hsa-miR-29c-3p/CCNL2 axis as a novel prognostic biomarker associated with immune infiltration in prostate cancer

Background

Prostate cancer (PCa) is currently the major malignancy in men. It is becoming increasingly clear that competitive endogenous RNA (ceRNA) regulation networks are important in a wide variety of cancers. Nevertheless, there is still much to learn about the biological functions of the ceRNA network in prostate cancer.

Methods

The ceRNA network was constructed using the "GDCRNATools" package. Based on survival analysis, we obtained AC005154.6/hsa-miR-29c-3p/CCNL2 for further analysis. The prognostic model based on this ceRNA network was constructed by univariate and multivariate Cox regression methods. Furthermore, functional enrichment analysis, mutation landscape analysis, immune infiltration analysis, drug sensitivity analysis, methylation analysis, pan-cancer analysis, and molecular experiments of CCNL2 were carried out to investigate the role of CCNL2 in tumorigenesis.

Results

We identified the AC005154.6/CCNL2 axis as a risk factor that can promote the progression of prostate cancer by bioinformatics analysis and molecular experiments. Immune infiltration analysis suggested that CCNL2 may act as a novel biomarker for treatment decisions. The methylation level of CCNL2 was significantly decreased in tumor samples, possibly contributing to the upregulation of CCNL2 in prostate cancer. Moreover, CCNL2 is differentially expressed in multiple cancers and is tightly correlated with immune infiltration.

Conclusion

The current study constructed a ceRNA network, AC005154.6/hsa-miR-29c-3p/CCNL2. Potentially, this biomarker can be used for early diagnosis and decision-making about prostate cancer treatment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-022-02779-5.

Overexpression of Ubiquitin-Conjugating Enzyme E2C Is Associated with Worsened Prognosis in Prostate Cancer

To evaluate the role of ubiquitin-conjugating enzyme E2C (UBE2C) in prostate cancer (PCa) progression and prognosis, the TCGA and our PCa tissue microarray cohort were included in the study. Weighted gene co-expression network analysis (WGCNA) and non-negative matrix factorization were used to cluster patients and to screen genes that play a vital role in PCa progression (hub gene). Immunohistochemistry staining was used to evaluate the protein level of UBE2C in prostatic tissues. Through WGCNA, we found a gene co-expression module (named the purple module) that is strongly associated with the Gleason score, pathologic T stage, and biochemical recurrent status. Genes in the purple module are enriched in cell cycle and P53 signaling and help us to cluster patients into two groups with distinctive biochemical recurrent survival rates and TP53 mutation statuses. Further analysis showed UBE2C served as a hub gene in the purple module. The expression of UBE2C in PCa was significantly higher than that in paracancerous tissues and was remarkably associated with pathologic grade, Gleason score, and prognosis in PCa patients. To conclude, UBE2C is a PCa-progress-related gene and a biomarker for PCa patients. Therapy targeting UBE2C may serve as a promising treatment of PCa in the future.

Development of machine learning classifiers to predict compound activity on prostate cancer cell lines

Prostate cancer is the most common type of cancer in men. The disease presents good survival rates if treated at the early stages. However, the evolution of the disease in its most aggressive variant remains without effective therapeutic answers. Therefore, the identification of novel effective therapeutics is urgently needed. On these premises, we developed a series of machine learning models, based on compounds with reported highly homogeneous cell-based antiproliferative assay data, able to predict the activity of ligands towards the PC-3 and DU-145 prostate cancer cell lines. The data employed in the development of the computational models was finely-tuned according to a series of thresholds for the classification of active/inactive compounds, to the number of features to be implemented, and by using 10 different machine learning algorithms. Models’ evaluation allowed us to identify the best combination of activity thresholds and ML algorithms for the classification of active compounds, achieving prediction performances with MCC values above 0.60 for PC-3 and DU-145 cells. Moreover, in silico models based on the combination of PC-3 and DU-145 data were also developed, demonstrating excellent precision performances. Finally, an analysis of the activity annotations reported for the ligands in the curated datasets were conducted, suggesting associations between cellular activity and biological targets that might be explored in the future for the design of more effective prostate cancer antiproliferative agents.

PROTEIN KINASE C ALPHA IS A CENTRAL NODE FOR TUMORIGENIC TRANSCRIPTIONAL NETWORKS IN HUMAN PROSTATE CANCER

Aberrant expression of protein kinase C (PKC) isozymes is a hallmark of cancer. The different members of the PKC family control cellular events associated with cancer development and progression. Whereas the classical/conventional PKCα isozyme has been linked to tumor suppression in most cancer types, here we demonstrate that this kinase is required for the mitogenic activity of aggressive human prostate cancer cells displaying aberrantly high PKCα expression. Immunohistochemical analysis showed abnormal up-regulation of PKCα in human primary prostate tumors. Interestingly, silencing PKCα expression from aggressive prostate cancer cells impairs cell cycle progression, proliferation and invasion, as well as their tumorigenic activity in a mouse xenograft model. Mechanistic analysis revealed that PKCα exerts a profound control of gene expression, particularly over genes and transcriptional networks associated with cell cycle progression and E2F transcription factors. PKCα RNAi depletion from PC3 prostate cancer cells led to a reduction in the expression of pro-inflammatory cytokine and epithelial-to-mesenchymal transition (EMT) genes, as well as a prominent down-regulation of the immune checkpoint ligand PD-L1. This PKCα-dependent gene expression profile was corroborated in silico using human prostate cancer databases. Our studies established PKCα as a multifunctional kinase that plays pleiotropic roles in prostate cancer, particularly by controlling genetic networks associated with tumor growth and progression. The identification of PKCα as a pro-tumorigenic kinase in human prostate cancer provides strong rationale for the development of therapeutic approaches towards targeting PKCα or its effectors.

Role of Rucaparib in the Treatment of Prostate Cancer: Clinical Perspectives and Considerations

Prostate cancer is one of the most common types of cancer worldwide and has strong genetic associations. This is important for the development of therapeutics for the condition, as metastatic castrate-resistant prostate cancer (mCRPC) is resistant to standard androgen deprivation therapy (ADT) and has a relatively poor prognosis. We conducted a literature review on rucaparib, a poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitor that is currently indicated for the treatment of patients with mCRPC who harbor mutations in BRCA1/2 (homologous recombination repair [HRR] genes) and who have already tried androgen receptor-axis-targeted therapies (ARAT) and a taxane chemotherapy. We describe rucaparib’s FDA approval, which was based on the results of the single-arm, open-label, Phase II TRITON2 clinical trial, which found an objective response rate (ORR) of 43.5%, a duration of response (DOR) of over six months in length and an acceptable safety profile. Rucaparib’s dosage and clinical considerations for use were also discussed. We also compared rucaparib’s use and safety profile with Olaparib, niraparib and talazoparib, three other PARP inhibitors tested for the treatment of mCRPC. Overall, initial results show that the safety profile of all four drugs in mCRPC was relatively similar, and further testing is currently indicated for all four. Differences in their metabolism, however, also warrant further research. The clinical validity of rucaparib will be tested by the follow-up TRITON3 clinical trial, which is comparing the effect of rucaparib compared to standard therapies for mCRPC harboring BRCA1/2 or ATM mutations. Other than TRITON3, other clinical trials are testing rucaparib’s ability against other cancers (prostate or otherwise) with HRR mutations, and also the efficacy of combination therapies involving rucaparib. Finally, more research is needed to elucidate rucaparib’s effect on HRR mutations other than BRCA1/2. Advancements in understanding the genetic landscape of mCRPC will also assist in understanding rucaparib’s full therapeutic potential.

Microbiota and prostate cancer

Prostate cancer remains the most frequently diagnosed non-skin malignancy in male patients, still representing one of the main causes of cancer-related death worldwide. Evidence is mounting that suggests the putative role of microbiota in the carcinogenesis as well as in modulating the efficacy and activity of anticancer treatments (e.g., chemotherapy, immune checkpoint inhibitors, targeted therapies) in a large number of hematological and solid tumors. However, few data are available regarding the interactions between prostate cancer and microbiome so far, in particular in terms of the impact of microbiota on disease development, pathogenesis, and response to medical treatments in this genitourinary malignancy. Herein, we provide an overview of current knowledge, novel insights and emerging therapeutic approaches related to gastrointestinal and genitourinary microbiome in prostate cancer patients, especially focusing on available evidence and published trials on this topic.

The long non-sacoding RNA TMEM147-AS1/miR-133b/ZNF587 axis regulates the Warburg effect and promotes prostatic carcinoma invasion and proliferation

BACKGROUND

The Warburg effect is a characteristic tumor cell behavior regarded as one of the cancer hallmarks and promotes tumor progression by promoting glucose uptake and lactate production. Long non-coding RNAs (lncRNAs) had been reported to emerge as a vital function in cancer development. The present research is designed to investigate the underlying molecular mechanism of lncRNA TMEM147 antisense RNA 1 (TMEM147-AS1) on aerobic glycolysis in prostatic carcinoma.

METHODS

lncRNA TMEM147-AS1, miR-133b and ZNF587 levels in prostatic carcinoma tissues and cells were detected by a polymerase chain reaction or western blot assays. Cell viability or invasion was determined by Edu (i.e. 5-ethynyl-2'-deoxyuridine), MTT (i.e. 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) or transwell assays. Hematoxylin and eosin and immunohistochemical staining were applied for histopathological examination. Tumor xenograft model was employed to investigate tumor growth in vivo. The combinative relationship between TMEM147-AS1 or ZNF587 and miR-133b was confirmed by a luciferase reporter assay.

RESULTS

TMEM147-AS1 and ZNF587 were up-regulated in prostatic carcinoma tissues and cells. Knockdown of TMEM147-AS1 or ZNF587 within prostate cancer cells significantly restrained cell viability, invasion and aerobic glycolysis in vitro and suppressed the neoplasia of prostatic carcinoma in vivo. miR-133b was directly targeted in both TMEM147-AS1 and ZNF587. Overexpression of miR-133b restrained prostate cancer cell viability, invasion and aerobic glycolysis. TMEM147-AS1 competitively targeted miR-133b, therefore counteracting miR-133b-mediated repression on ZNF587.

CONCLUSIONS

TMEM147-AS1 plays a tumor-promoting action in prostatic carcinoma aerobic glycolysis via affecting the miR-133b/ZNF587 axis, therefore regulating prostatic carcinoma cells invasion and proliferation. These outcomes implied that TMEM147-AS1 could be an effective treatment strategy for further study of prostatic carcinoma.

Apelin Promotes Prostate Cancer Metastasis by Downregulating TIMP2 via Increases in miR-106a-5p Expression

Prostate cancer commonly affects the urinary tract of men and metastatic prostate cancer has a very low survival rate. Apelin belongs to the family of adipokines and is associated with cancer development and metastasis. However, the effects of apelin in prostate cancer metastasis is undetermined. Analysis of the database revealed a positive correlation between apelin level with the progression and metastasis of prostate cancer patients. Apelin treatment facilitates cell migration and invasion through inhibiting tissue inhibitor of metalloproteinase 2 (TIMP2) expression. The increasing miR-106a-5p synthesis via c-Src/PI3K/Akt signaling pathway is controlled in apelin-regulated TIMP2 production and cell motility. Importantly, apelin blockade inhibits prostate cancer metastasis in the orthotopic mouse model. Thus, apelin is a promising therapeutic target for curing metastatic prostate cancer.

CRISPR/Cas9-mediated deletion of Interleukin-30 suppresses IGF1 and CXCL5 and boosts SOCS3 reducing prostate cancer growth and mortality

BACKGROUND

Metastatic prostate cancer (PC) is a leading cause of cancer death in men worldwide. Targeting of the culprits of disease progression is an unmet need. Interleukin (IL)-30 promotes PC onset and development, but whether it can be a suitable therapeutic target remains to be investigated. Here, we shed light on the relationship between IL30 and canonical PC driver genes and explored the anti-tumor potential of CRISPR/Cas9-mediated deletion of IL30.

METHODS

PC cell production of, and response to, IL30 was tested by flow cytometry, immunoelectron microscopy, invasion and migration assays and PCR arrays. Syngeneic and xenograft models were used to investigate the effects of IL30, and its deletion by CRISPR/Cas9 genome editing, on tumor growth. Bioinformatics of transcriptional data and immunopathology of PC samples were used to assess the translational value of the experimental findings.

RESULTS

Human membrane-bound IL30 promoted PC cell proliferation, invasion and migration in association with STAT1/STAT3 phosphorylation, similarly to its murine, but secreted, counterpart. Both human and murine IL30 regulated PC driver and immunity genes and shared the upregulation of oncogenes, BCL2 and NFKB1, immunoregulatory mediators, IL1A, TNF, TLR4, PTGS2, PD-L1, STAT3, and chemokine receptors, CCR2, CCR4, CXCR5. In human PC cells, IL30 improved the release of IGF1 and CXCL5, which mediated, via autocrine loops, its potent proliferative effect. Deletion of IL30 dramatically downregulated BCL2, NFKB1, STAT3, IGF1 and CXCL5, whereas tumor suppressors, primarily SOCS3, were upregulated. Syngeneic and xenograft PC models demonstrated IL30's ability to boost cancer proliferation, vascularization and myeloid-derived cell infiltration, which were hindered, along with tumor growth and metastasis, by IL30 deletion, with improved host survival. RNA-Seq data from the PanCancer collection and immunohistochemistry of high-grade locally advanced PCs demonstrated an inverse association (chi-squared test, p = 0.0242) between IL30 and SOCS3 expression and a longer progression-free survival of patients with IL30^NegSOCS3^PosPC, when compared to patients with IL30^PosSOCS3^NegPC.

CONCLUSIONS

Membrane-anchored IL30 expressed by human PC cells shares a tumor progression programs with its murine homolog and, via juxtacrine signals, steers a complex network of PC driver and immunity genes promoting prostate oncogenesis. The efficacy of CRISPR/Cas9-mediated targeting of IL30 in curbing PC progression paves the way for its clinical use.

An unusual delayed rectal metastasis from prostate cancer masquerading as primary rectal cancer

Introduction and importance

Rectal metastasis of prostate cancer origin is exceedingly rare. Its clinical presentation, endoscopic morphology, and histopathology are similar to primary rectal cancer. Misdiagnosis may lead to inappropriate treatment.

Case presentation

We report a case of a gentleman in his 80's with a history of treated prostate cancer T3aN0M0 with radical prostatectomy sixteen years ago. He presented with one-year complaints of altered bowel habits and weight loss. Physical and rectal examination was unremarkable. Colonoscopy manifested some inflammatory changes in the rectum. The pelvis magnetic resonance imaging (MRI) showed an abnormal posterior rectal wall thickening 2 cm above the anal canal. Biopsy confirmed poorly differentiated adenocarcinoma of prostate origin. The staging workup was negative for other distant metastasis. After a multidisciplinary decision, the patient was started on androgen deprivation therapy and given palliative radiotherapy to the rectum. Six weeks later, the patient was stable with mild radiation proctitis.

Clinical discussion

Management of rectal metastasis varies depending on the patient's choice, the extent of metastatic burden, symptoms, age, life expectancy, quality of life and comorbidities. While surgery remains the standard of care, other option including radiotherapy, hormonal therapy and chemotherapy has been documented in the literature with survival of few weeks to 2 years.

Conclusion

Delayed rectal metastasis of prostate cancer after radical prostatectomy is a rare entity. Its clinical presentation and endoscopic and histopathological findings of rectal metastasis are similar to primary colorectal cancer, making diagnosis more demanding.

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Rectum is a rare isolated site of metastasis from prostate cancer.

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Symptoms and endoscopic morphology of rectal metastasis are similar to primary rectal cancer.

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Prostate-specific antigen is not always raised in rectal metastasis.

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Emergent lower gastrointestinal symptoms in patients with a history of prostate cancer warrants a multidisciplinary approach to reach an accurate diagnosis and prompt treatment.

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Management of rectal metastasis depends on patient desire, the severity of symptoms, age, quality of life, life expectancy and comorbidities.

Review of prostate cancer genomic studies in Africa

Prostate cancer (PCa) is the second most commonly diagnosed in men worldwide and one of the most frequent cancers in men in Africa. The heterogeneity of this cancer fosters the need to identify potential genetic risk factors/biomarkers. Omics variations may significantly contribute to early diagnosis and personalized treatment. However, there are few genomic studies of this disease in African populations. This review sheds light on the status of genomics research on PCa in Africa and outlines the common variants identified thus far. The allele frequencies of the most significant SNPs in Afro-native, Afro-descendants, and European populations were compared. We advocate how these few but promising data will aid in understanding, better diagnosing, and precisely treating this cancer and the need for further collaborative research on the genomics of PCa in the African continent.

Xenografts on nude mouse diaphragm of human DU145 prostate carcinoma cells: mesothelium removal by outgrowths and angiogenesis

Human prostate carcinoma DU145 cells, androgen-independent malignant cells, implanted in the athymic nu/nu male mouse, developed numerous tumors on peritoneal and retro-peritoneal organs whose growth aspects and vascular supply have yet to be investigated with fine structure techniques. A series of necropsies from moribund implanted mice diaphragms were examined with light, scanning, and transmission electron microscopy. DU145 xenografts installations, far away from the implanted site, were described as the smallest installation to large diaphragm outgrowths in moribund mice. Carcinomas did not show extracellular matrix and, reaching more than 0.15 mm in thickness, they revealed new structures in these outgrowths. Voids to be gland-like structures with mediocre secretion and, unexpectedly, intercellular spaces connected with fascicles of elongated DU145 cells that merged with a vascular supply originated from either the tumor cells and/or some perimysium vessels. In the largest carcinomas, most important vascular invasions coincidently accompanied the mouse lethality, similarly to human cancers. This androgen-independent model would be useful to study tumor outgrowth's changes related to testing anticancer strategy, including anti-angiogenic therapies involving toxicity, simultaneously with those of other vital organs with combined biomolecular and fine structure techniques.

Heat Shock Protein 70 and 90 Family in Prostate Cancer

Prostate cancer (PCa) is the second most frequent cancer that affects aging men worldwide. However, its exact pathogenesis has not been fully elucidated. The heat shock protein (HSP) family has cell-protective properties that may promote tumor growth and protect cancer cells from death. On a cellular level, HSP molecules have a strong relationship with multiple important biological processes, such as cell differentiation, epithelial-mesenchymal transition (EMT), and fibrosis. Because of the facilitation of HSP family molecules on tumorigenesis, a number of agents and inhibitors are being developed with potent antitumor effects whose target site is the critical structure of HSP molecules. Among all target molecules, HSP70 family and HSP90 are two groups that have been well studied, and therefore, the development of their inhibitors makes great progress. Only a small number of agents, however, have been clinically tested in recruited patients. As a result, more clinical studies are warranted for the establishment of the relationship between the HSP70 family, alongside the HSP90 molecule, and prostate cancer treatment.

Prostate cancer cells of increasing metastatic potential exhibit diverse contractile forces, cell stiffness, and motility in a microenvironment stiffness-dependent manner

During metastasis, all cancer types must migrate through crowded multicellular environments. Simultaneously, cancers appear to change their biophysical properties. Indeed, cell softening and increased contractility are emerging as seemingly ubiquitous biomarkers of metastatic progression which may facilitate metastasis. Cell stiffness and contractility are also influenced by the microenvironment. Stiffer matrices resembling the tumor microenvironment cause metastatic cells to contract more strongly, further promoting contractile tumorigenic phenotypes. Prostate cancer (PCa), however, appears to deviate from these common cancer biophysics trends; aggressive metastatic PCa cells appear stiffer, rather than softer, to their lowly metastatic PCa counterparts. Although metastatic PCa cells have been reported to be more contractile than healthy cells, how cell contractility changes with increasing PCa metastatic potential has remained unknown. Here, we characterize the biophysical changes of PCa cells of various metastatic potential as a function of microenvironment stiffness. Using a panel of progressively increasing metastatic potential cell lines (22RV1, LNCaP, DU145, and PC3), we quantified their contractility using traction force microscopy (TFM), and measured their cortical stiffness using optical magnetic twisting cytometry (OMTC) and their motility using time-lapse microscopy. We found that PCa contractility, cell stiffness, and motility do not universally scale with metastatic potential. Rather, PCa cells of various metastatic efficiencies exhibit unique biophysical responses that are differentially influenced by substrate stiffness. Despite this biophysical diversity, this work concludes that mechanical microenvironment is a key determinant in the biophysical response of PCa with variable metastatic potentials. The mechanics-oriented focus and methodology of the study is unique and complementary to conventional biochemical and genetic strategies typically used to understand this disease, and thus may usher in new perspectives and approaches.

Prostate cancer as a dedifferentiated organ: androgen receptor, cancer stem cells, and cancer stemness

Cancer progression is characterized and driven by gradual loss of a differentiated phenotype and gain of stem cell-like features. In prostate cancer (PCa), androgen receptor (AR) signaling is important for cancer growth, progression, and emergence of therapy resistance. Targeting the AR signaling axis has been, over the decades, the mainstay of PCa therapy. However, AR signaling at the transcription level is reduced in high-grade cancer relative to low-grade PCa and loss of AR expression promotes a stem cell-like phenotype, suggesting that emergence of resistance to AR-targeted therapy may be associated with loss of AR signaling and gain of stemness. In the present mini-review, we first discuss PCa from the perspective of an abnormal organ with increasingly deregulated differentiation, and discuss the role of AR signaling during PCa progression. We then focus on the relationship between prostate cancer stem cells (PCSCs) and AR signaling. We further elaborate on the current methods of using transcriptome-based stemness-enriched signature to evaluate the degree of oncogenic dedifferentiation (cancer stemness) in pan-cancer datasets, and present the clinical significance of scoring transcriptome-based stemness across the spectrum of PCa development. Our discussions highlight the importance to evaluate the dynamic changes in both stem cell-like features (stemness score) and AR signaling activity across the PCa spectrum.

Boosting the Immune Response—Combining Local and Immune Therapy for Prostate Cancer Treatment

Due to its slow progression and susceptibility to radical forms of treatment, low-grade PC is associated with high overall survival (OS). With the clinical progression of PC, the therapy is becoming more complex. The immunosuppressive tumor microenvironment (TME) makes PC a difficult target for most immunotherapeutics. Its general immune resistance is established by e.g., immune evasion through Treg cells, synthesis of immunosuppressive mediators, and the defective expression of surface neoantigens. The success of sipuleucel-T in clinical trials initiated several other clinical studies that specifically target the immune escape of tumors and eliminate the immunosuppressive properties of the TME. In the settings of PC treatment, this can be commonly achieved with radiation therapy (RT). In addition, focal therapies usually applied for localized PC, such as high-intensity focused ultrasound (HIFU) therapy, cryotherapy, photodynamic therapy (PDT), and irreversible electroporation (IRE) were shown to boost the anti-cancer response. Nevertheless, the present guidelines restrict their application to the context of a clinical trial or a prospective cohort study. This review explains how RT and focal therapies enhance the immune response. We also provide data supporting the combination of RT and focal treatments with immune therapies.

Prostate cancer in omics era

Recent advances in omics technology have prompted extraordinary attempts to define the molecular changes underlying the onset and progression of a variety of complex human diseases, including cancer. Since the advent of sequencing technology, cancer biology has become increasingly reliant on the generation and integration of data generated at these levels. The availability of multi-omic data has transformed medicine and biology by enabling integrated systems-level approaches. Multivariate signatures are expected to play a role in cancer detection, screening, patient classification, assessment of treatment response, and biomarker identification. This review reports current findings and highlights a number of studies that are both novel and groundbreaking in their application of multi Omics to prostate cancer.

Bovine Lactoferrin Induces Cell Death in Human Prostate Cancer Cells

Bovine lactoferrin (bLf) is a multifunctional protein widely associated with anticancer activity. Prostate cancer is the second most frequent type of cancer worldwide. This study was aimed at evaluating the influence of bLf on cell viability, cell cycle progression, reactive oxygen species (ROS) production, and rate of apoptosis in the human prostate cancer cell line (DU-145). MTT assay and trypan blue exclusion were used to analyze cell viability. Morphological changes were analyzed through optical microscopy after 24 h and 48 h of bLf treatment. FITC-bLf internalization and cellular damage were observed within 24 h by confocal fluorescence microscopy. Cell cycle analyses were performed by flow cytometry and propidium iodide. For caspases 3/7 activation and reactive oxygen species production evaluation, cells were live-imaged using the high-throughput system Operetta. The cell viability assays demonstrated that bLf induces cell death and morphological changes after 24 h and 48 h of treatment compared to control on DU-145 cells. The bLf internalization was detected in DU-145 cells, G₁-phase arrest of the cell cycle, caspase 3/7 activation, and increased oxidative stress on bLf-treated cells. Our data support that bLf has an important anticancer activity, thus offering new perspectives in preventing and treating prostate cancer.

Functions and mechanisms of N6‑methyladenosine in prostate cancer (Review)

Prostate cancer (PCa) has long been a major public health problem affecting men worldwide. Even with treatment, it can develop into castration-resistant PCa. With the continuous advancement in epigenetics, researchers have explored N6-methyladenosine (m⁶A) in search of a more effective and lasting treatment for PCa. m⁶A is widely distributed in mammalian cells and influences various aspects of mRNA metabolism. Recently, it has been associated with the development or suppression of various types of cancer, including PCa. This review summarizes the recent findings on m⁶A regulation and its functions and mechanisms in cells, focusing on the various functional proteins operating within m⁶A in PCa cells. Moreover, the potential clinical value of exploiting m⁶A modification as an early diagnostic marker in PCa diagnosis and therapeutics was discussed. m⁶A may also be used as an indicator to evaluate treatment outcome and prognosis.

The impact of genetic aberrations on response to radium-223 treatment for castration-resistant prostate cancer with bone metastases

BACKGROUND

Radium (Ra)-223 is an established treatment option for patients with metastatic castrate-resistant prostate cancer (mCRPC) who have symptomatic bone metastases without soft tissue disease. Studies have indicated genetic aberrations that regulate DNA damage response (DDR) in prostate cancer can increase susceptibility to treatments such as poly ADP-ribose polymerase inhibitors and platinum-based therapies. This study aims to evaluate mCRPC response to Ra-223 stratified by tumor genomics.

METHODS

This is a retrospective study of mCRPC patients who received Ra-223 and genetic testing within the Mayo Clinic database (Arizona, Florida, and Minnesota) and Tulane Cancer Center. Patient demographics, genetic aberrations, treatment responses in terms of alkaline phosphatase (ALP) and prostate-specific antigen (PSA), and survival were assessed. Primary end points were ALP and PSA response. Secondary end points were progression-free survival (PFS) and overall survival (OS) from time of first radium treatment.

RESULTS

One hundred and twenty-seven mCRPC patients treated with Ra-223 had germline and/or somatic genetic sequencing. The median age at time of diagnosis and Ra-223 treatment was 61.0 and 68.6 years, respectively. Seventy-nine (62.2%) had Gleason score ≥ 8 at time of diagnosis. 50.4% received prior docetaxel, and 12.6% received prior cabazitaxel. Notable alterations include TP53 (51.7%), BRCA 1/2 (15.0%), PTEN (13.4%), ATM (11.7%), TMPRSS2-ERG (8.2%), RB deletion (3.4%), and CDK12 (1.9%). There was no significant difference in ALP or PSA response among the different genetic aberrations. Patients with a TMPRSS2-ERG mutation exhibited a trend toward lower OS 15.4 months (95% confidence interval [CI] 10.0-NR) versus 26.8 months (95% CI 20.9-35.1). Patients with an RB deletion had a lower PFS 6.0 months (95% CI 1.28-NR) versus 9.0 months (95% CI 7.3-11.1) and a lower OS 13.9 months (95% CI 5.2-NR) versus 26.5 months (95% CI 19.8-33.8).

CONCLUSIONS

Among mCRPC patients treated with Ra-223 at Mayo Clinic and Tulane Cancer Center, we did not find any clear negative predictors of biochemical response or survival to treatment. TMPRSS2-ERG and RB mutations were associated with a worse OS. Prospective studies and larger sample sizes are needed to determine the impact of genetic aberrations in response to Ra-223.

The androgen receptor couples promoter recruitment of RNA processing factors to regulation of alternative polyadenylation at the 3' end of transcripts

Prostate cancer (PC) relies on androgen receptor (AR) signaling. While hormonal therapy (HT) is efficacious, most patients evolve to an incurable castration-resistant stage (CRPC). To date, most proposed mechanisms of acquired resistance to HT have focused on AR transcriptional activity. Herein, we uncover a new role for the AR in alternative cleavage and polyadenylation (APA). Inhibition of the AR by Enzalutamide globally regulates APA in PC cells, with specific enrichment in genes related to transcription and DNA topology, suggesting their involvement in transcriptome reprogramming. AR inhibition selects promoter-distal polyadenylation sites (pAs) enriched in cis-elements recognized by the cleavage and polyadenylation specificity factor (CPSF) complex. Conversely, promoter-proximal intronic pAs relying on the cleavage stimulation factor (CSTF) complex are repressed. Mechanistically, Enzalutamide induces rearrangement of APA subcomplexes and impairs the interaction between CPSF and CSTF. AR inhibition also induces co-transcriptional CPSF recruitment to gene promoters, predisposing the selection of pAs depending on this complex. Importantly, the scaffold CPSF160 protein is up-regulated in CRPC cells and its depletion represses HT-induced APA patterns. These findings uncover an unexpected role for the AR in APA regulation and suggest that APA-mediated transcriptome reprogramming represents an adaptive response of PC cells to HT.

Dual contribution of the mTOR pathway and of the metabolism of amino acids in prostate cancer

BACKGROUND

Prostate cancer is the leading cause of cancer in men, and its incidence increases with age. Among other risk factors, pre-existing metabolic diseases have been recently linked with prostate cancer, and our current knowledge recognizes prostate cancer as a condition with important metabolic anomalies as well. In malignancies, metabolic disorders are commonly associated with aberrations in mTOR, which is the master regulator of protein synthesis and energetic homeostasis. Although there are reports demonstrating the high dependency of prostate cancer cells for lipid derivatives and even for carbohydrates, the understanding regarding amino acids, and the relationship with the mTOR pathway ultimately resulting in metabolic aberrations, is still scarce.

CONCLUSIONS AND PERSPECTIVES

In this review, we briefly provide evidence supporting prostate cancer as a metabolic disease, and discuss what is known about mTOR signaling and prostate cancer. Next, we emphasized on the amino acids glutamine, leucine, serine, glycine, sarcosine, proline and arginine, commonly related to prostate cancer, to explore the alterations in their regulatory pathways and to link them with the associated metabolic reprogramming events seen in prostate cancer. Finally, we display potential therapeutic strategies for targeting mTOR and the referred amino acids, as experimental approaches to selectively attack prostate cancer cells.

Cancer associated fibroblasts secreted exosomal miR-1290 contributes to prostate cancer cell growth and metastasis via targeting GSK3β

Cancer-associated fibroblasts (CAFs) play crucial roles in mediating tumor growth and metastasis via transferring exosomes to neighboring cells, whereas the mechanisms by which CAFs regulate the tumorgenesis of prostate cancer (PC) remain largely unknown. In this study, CAFs and normal fibroblasts (NFs) were isolated from PC tissues and adjacent normal tissues, respectively. Exosomes (NFs-Exo and CAFs-Exo) were then isolated from the supernatant of NFs and CAFs. Next, the differentially expressed miRNAs (DEMs) between NFs-Exo and CAFs-Exo were identified using RNA-sequencing. Cell viability, migration and invasion were detected with CCK-8 and Transwell assays. Protein expression was measured with western blot. We found that CAFs-Exo remarkably enhanced PC cell migration, invasion, stemness, epithelial-mesenchymal transition (EMT) and metastasis. Significantly, miR-1290 level was upregulated in CAFs-Exo compared to NFs-Exo. In addition, CAFs could transfer exosomes to PC cells, resulting in a marked increase of miR-1290 level in cells. Moreover, exosomal miR-1290 could inhibit GSK3β/β-catenin signaling by binding with the downstream target GSK3β mRNA. Meanwhile, miR-1290 antagomir notably reversed the effects of CAFs-Exo on PC cells through activating GSK3β/β-catenin signaling. Collectively, exosomal miR-1290 from CAFs could promote PC cell growth and metastasis via inhibiting GSK3β/β-catenin signaling, suggesting that miR-1290 may serve as potential therapeutic target for the treatment of PC.

Mental Health in Urologic Oncology

This article is a systematic review of mental health in urologic oncology patients with prostate cancer (PCa), bladder cancer (BC), renal cell carcinoma (RCC), testicular cancer (TC), or penile cancer (PeCa). For all pathologies, a focus on increasing quality of life post-treatment demonstrated a positive impact in reducing Mental Health Illness (MHI) prevalence. Cancer specific mental health care may be given to patients to reduce suicide risk in BC patients and sexual identify and masculinity counseling may improve mental health for TC or PeCa patients. In order to better accommodate patient’s mental health needs when undergoing GU cancer treatment, we recommend incorporation of mental health metrics such as questionnaires to assess early treatment of MHI, a greater emphasis on psychosocial support with the patient’s loved ones, peers, and healthcare team, alongside advising healthy habits such as exercise which has been shown to drastically reduce MHI incidence across all pathologies. We hope that these measures conducted by urologists and oncologists, alongside possible coordination with psychiatrists and psychologists for psychotherapy, psychopharmacology, and neuro-stimulation treatment modems may be helpful in the long term to reduce MHI incidence in urology oncology patients. Given the higher incidence of MHI in oncology patients and in the patient population after the Covid-19 pandemic, MHI awareness in the sphere of urologic oncologic treatment continues to be crucial when creating a collaborative treatment platform for patients.

Single-cell RNA sequencing reveals the cellular and molecular changes that contribute to the progression of lung adenocarcinoma

Pure ground glass nodules (GGNs) and solid nodules (SNs) represent early and relatively late stages of lung adenocarcinoma (LUAD) in radiology, respectively. The cellular and molecular characteristics of pure GGNs and SNs have not been comprehensively elucidated. Additionally, the mechanism driving the progression of lung adenocarcinoma from pure GGN to SN in radiology is also elusive. In this study, by analyzing the single-cell transcriptomic profiles of 76,762 cells from four pure GGNs, four SNs, and four normal tissues, we found that anti-tumor immunity mediated by NK and CD8+T cells gradually weakened with the progression of LUAD and humoral immunity mediated by plasma B cells was more active in SNs. Additionally, the proliferation ability of some special epithelial cell increased during the progression process from pure GGN to SN. Furthermore, stromal cells and M2 macrophages could assist the progression of LUAD. Through comprehensive analyses, we revealed dynamic changes in cellular components and intercellular interactions during the progression of LUAD. These findings could facilitate our understanding of LUAD and discovery of novel therapeutic targets.

Androgen receptor variant-7 regulation by tenascin-c induced src activation

BACKGROUND

Bone metastatic prostate cancer does not completely respond to androgen-targeted therapy and generally evolves into lethal castration resistant prostate cancer (CRPC). Expression of AR-V7- a constitutively active, ligand independent splice variant of AR is one of the critical resistant mechanisms regulating metastatic CRPC. TNC is an extracellular matrix glycoprotein, crucial for prostate cancer progression, and associated with prostate cancer bone metastases. In this study, we investigated the mechanisms that regulate AR-V7 expression in prostate cancer cells interacting with osteogenic microenvironment including TNC.

METHODS

Prostate cancer/preosteoblast heterotypical organoids were evaluated via immunofluorescence imaging and gene expression analysis using RT-qPCR to assess cellular compartmentalization, TNC localization, and to investigate regulation of AR-V7 in prostate cancer cells by preosteoblasts and hormone or antiandrogen action. Prostate cancer cells cultured on TNC were assessed using RT-qPCR, Western blotting, cycloheximide chase assay, and immunofluorescence imaging to evaluate (1) regulation of AR-V7, and (2) signaling pathways activated by TNC. Identified signaling pathway induced by TNC was targeted using siRNA and a small molecular inhibitor to investigate the role of TNC-induced signaling activation in regulation of AR-V7. Both AR-V7- and TNC-induced signaling effectors were targeted using siRNA, and TNC expression assessed to evaluate potential feedback regulation.

RESULTS

Utilizing heterotypical organoids, we show that TNC is an integral component of prostate cancer interaction with preosteoblasts. Interaction with preosteoblasts upregulated both TNC and AR-V7 expression in prostate cancer cells which was suppressed by testosterone but elevated by antiandrogen enzalutamide. Interestingly, the results demonstrate that TNC-induced Src activation regulated AR-V7 expression, post-translational stability, and nuclear localization in prostate cancer cells. Treatment with TNC neutralizing antibody, Src knockdown, and inhibition of Src kinase activity repressed AR-V7 transcript and protein. Reciprocally, both activated Src and AR-V7 were observed to upregulate autocrine TNC gene expression in prostate cancer cells.

CONCLUSION

Overall, the findings reveal that prostate cancer cell interactions with the cellular and ECM components in the osteogenic microenvironment plays critical role in regulating AR-V7 associated with metastatic CRPC. Video Abstract.

Prostate Infiltration by Treg and Th17 Cells as an Immune Response to Propionibacterium acnes Infection in the Course of Benign Prostatic Hyperplasia and Prostate Cancer

Benign prostatic hyperplasia (BPH) and prostate cancer (PCa) belong to the most frequent diseases in ageing men. It has been proposed that prostate chronic inflammation is a risk factor for the development of both BPH and PCa. However, potential stimuli that cause or maintain inflammation in the prostate gland are still poorly characterized. Bacterial infections seems to be one of the potential sources of prostatitis. Recent studies show that Propionibacterium acnes (P. acnes) is the most prevalent microorganism in the prostate gland and may be a predisposing factor for inflammation of prostatic tissue. It indicates that P. acnes may contribute to cancer development by enhancing proinflammatory responses, as well as by modifying the prostate extracellular environment. In this review, we discuss the potential role of P. acnes in the development of BPH and PCa and highlight the importance of regulatory T CD4(+)FoxP3(+) (Treg) and Th17 cells in response to P. acnes infection in the context of both prostate diseases.

The potential of cell-free and exosomal microRNAs as biomarkers in liquid biopsy in patients with prostate cancer

PURPOSE

Prostate cancer (PCa) is the 4th most diagnosed cancer and the 8th leading cause of cancer-related death worldwide. Currently, clinical risk stratification models including factors like PSA levels, Gleason score, and digital rectal examination are used for this purpose. There is a need for novel biomarkers that can distinguish between indolent and aggressive pathology and reduce the risk of overdiagnosis/overtreatment. Liquid biopsy has a non-invasive character, can lead to less morbidity and provide new biomarkers, such as miRNAs, that regulate diverse important cellular processes. Here, we report an extended revision about the role of cell-free and exosomal miRNAs (exomiRNAs) as biomarkers for screening, diagnosis, prognosis, or treatment of PCa.

METHODS

A comprehensive review of the published literature was conducted focusing on the usefulness, advantages, and clinical applications of cell-free and exomiRNAs in serum and plasma. Using PubMed database 53 articles published between 2012 and 2021 were selected and discussed from the perspective of their use as diagnostic, prognostic and therapeutic biomarkers for PCa.

RESULTS

We identify 119 miRNAs associated with PCa development and the cell-free and exosomal miR-21, miR-141, miR-200c, and miR-375 were consistently associated with progression in multiple cohorts/studies. However, standardized experimental procedures, and well-defined and clinically relevant cohort studies are urgently needed to confirm the biomarker potential of cell-free and exomiRNAs in serum or plasma.

CONCLUSION

Cell-free and exomiRNAs in serum or plasma are promising tools for be used as non-invasive biomarkers for diagnostic, prognosis, therapy improvement and clinical outcome prediction in PCa patients.

Curcumol Inhibits the Development of Prostate Cancer by miR-125a/STAT3 Axis

Aim

This study aimed to learn the antineoplastic activity of curcumol (Cur) on prostate cancer (PCa) and elucidate its potential molecular mechanism.

Methods

The proliferation, invasion, and migration of PCa cells (PC3 and 22RV1) were detected by the cell counting kit 8 (CCK8), transwell, and wound healing assay, respectively. The expression of genes and proteins was analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting (WB), respectively. The protein expression in tissues and cells was tested through immunohistochemistry (IHC) and immunocytochemistry (ICC). Enzyme-linked immunosorbent assay (ELISA) was utilized to quantify the level of epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF). The interaction between microRNA125a (miR-125a) and the signal transducer and activator of transcription 3 (STAT3) was confirmed via dual-luciferase reporter assay.

Results

Cur effectively restrained the proliferation, invasion, and migration of PC3 and 22RV1 cells. After Cur intervention, miR-125a, miR-375, miR-149, miR-183, and miR-106b were all upregulated in PC3 cells, among which miR-125a was the most significantly upregulated. Dual-luciferase reporter assay combined with qRT-PCR and WB experiments confirmed that miR-125a targeted STAT3. Both in vitro and in vivo, Cur enhanced miR-125a expression and suppressed the activation of the STAT3 pathway in PCa. Also, Cur effectively inhibited the growth of PCa.

Conclusion

Cur inhibited the development of PCa by miR-125a/STAT3 axis. This may provide a potential agent for treating PCa.

Androgen receptor signaling and spatial chromatin organization in castration-resistant prostate cancer

Prostate cancer is one of the leading causes of cancer death and affects millions of men in the world. The American Cancer Society estimated about 34,500 deaths from prostate cancer in the United States in year 2022. The Androgen receptor (AR) signaling is a major pathway that sustains local and metastatic prostate tumor growth. Androgen-deprivation therapy (ADT) is the standard of care for metastatic prostate cancer patient and can suppress the tumor growth for a median of 2–3 years. Unfortunately, the malignancy inevitably progresses to castration-resistant prostate cancer (CRPC) which is more aggressive and no longer responsive to ADT. Surprisingly, for most of the CPRC patients, cancer growth still depends on androgen receptor signaling. Accumulating evidence suggests that CRPC cells have rewired their transcriptional program to retain AR signaling in the absence of androgens. Besides AR, other transcription factors also contribute to the resistance mechanism through multiple pathways including enhancing AR signaling pathway and activating other complementary signaling pathways for the favor of AR downstream genes expression. More recent studies have shown the role of transcription factors in reconfiguring chromatin 3D structure and regulating topologically associating domains (TADs). Pioneer factors, transcription factors and coactivators form liquid-liquid phase separation compartment that can modulate transcriptional events along with configuring TADs. The role of AR and other transcription factors on chromatin structure change and formation of condensate compartment in prostate cancer cells has only been recently investigated and appreciated. This review intends to provide an overview of transcription factors that contribute to AR signaling through activation of gene expression, governing 3D chromatin structure and establishing phase to phase separation. A more detailed understanding of the spatial role of transcription factors in CRPC might provide novel therapeutic targets for the treatment of CRPC.

Integrated analysis of mRNA-single nucleotide polymorphism-microRNA interaction network to identify biomarkers associated with prostate cancer

Background: Prostate cancer is one of the most common malignancies among men worldwide currently. However, specific mechanisms of prostate cancer were still not fully understood due to lack of integrated molecular analyses. We performed this study to establish an mRNA-single nucleotide polymorphism (SNP)-microRNA (miRNA) interaction network by comprehensive bioinformatics analysis, and search for novel biomarkers for prostate cancer.

Materials and methods: mRNA, miRNA, and SNP data were acquired from Gene Expression Omnibus (GEO) database. Differential expression analysis was performed to identify differentially expressed genes (DEGs) and miRNAs (DEMs). Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses, protein-protein interaction (PPI) analysis and expression quantitative trait loci (eQTL) analysis of DEGs were conducted. SNPs related to DEMs (miRSNPs) were downloaded from the open-source website MirSNP and PolymiRTS 3.0. TargetScan and miRDB databases were used for the target mRNA prediction of miRNA. The mRNA-SNP-miRNA interaction network was then constructed and visualized by Cytoscape 3.9.0. Selected key biomarkers were further validated using the Cancer Genome Atlas (TCGA) database. A nomogram model was constructed to predict the risk of prostate cancer.

Results: In our study, 266 DEGs and 11 DEMs were identified. KEGG pathway analysis showed that DEGs were strikingly enriched in focal adhesion and PI3K-Akt signaling pathway. A total of 60 mRNA-SNP-miRNAs trios were identified to establish the mRNA-SNP-miRNA interaction network. Seven mRNAs in mRNA-SNP-miRNA network were consistent with the predicted target mRNAs of miRNA. These results were largely validated by the TCGA database analysis. A nomogram was constructed that contained four variables (ITGB8, hsa-miR-21, hsa-miR-30b and prostate-specific antigen (PSA) value) for predicting the risk of prostate cancer.

Conclusion: Our study established the mRNA-SNP-miRNA interaction network in prostate cancer. The interaction network showed that hsa-miR-21, hsa-miR-30b, and ITGB8 may be utilized as new biomarkers for prostate cancer.

RET signaling pathway and RET inhibitors in human cancer

Rearranged during transfection (RET) receptor tyrosine kinase was first identified over thirty years ago as a novel transforming gene. Since its discovery and subsequent pathway characterization, RET alterations have been identified in numerous cancer types and are most prevalent in thyroid carcinomas and non-small cell lung cancer (NSCLC). In other tumor types such as breast cancer and salivary gland carcinomas, RET alterations can be found at lower frequencies. Aberrant RET activity is associated with poor prognosis of thyroid and lung carcinoma patients, and is strongly correlated with increased risk of distant metastases. RET aberrations encompass a variety of genomic or proteomic alterations, most of which confer constitutive activation of RET. Activating RET alterations, such as point mutations or gene fusions, enhance activity of signaling pathways downstream of RET, namely PI3K/AKT, RAS/RAF, MAPK, and PLCγ pathways, to promote cell proliferation, growth, and survival. Given the important role that mutant RET plays in metastatic cancers, significant efforts have been made in developing inhibitors against RET kinase activity. These efforts have led to FDA approval of Selpercatinib and Pralsetinib for NSCLC, as well as, additional selective RET inhibitors in preclinical and clinical testing. This review covers the current biological understanding of RET signaling, the impact of RET hyperactivity on tumor progression in multiple tumor types, and RET inhibitors with promising preclinical and clinical efficacy.

Hypoxia-mediated stabilization of HIF1A in prostatic intraepithelial neoplasia promotes cell plasticity and malignant progression

Prostate cancer (PCa) is a leading cause of cancer-related deaths. The slow evolution of precancerous lesions to malignant tumors provides a broad time frame for preventing PCa. To characterize prostatic intraepithelial neoplasia (PIN) progression, we conducted longitudinal studies on Pten^(i)pe-/- mice that recapitulate prostate carcinogenesis in humans. We found that early PINs are hypoxic and that hypoxia-inducible factor 1 alpha (HIF1A) signaling is activated in luminal cells, thus enhancing malignant progression. Luminal HIF1A dampens immune surveillance and drives luminal plasticity, leading to the emergence of cells that overexpress Transglutaminase 2 (TGM2) and have impaired androgen signaling. Elevated TGM2 levels in patients with PCa are associated with shortened progression-free survival after prostatectomy. Last, we show that pharmacologically inhibiting HIF1A impairs cell proliferation and induces apoptosis in PINs. Therefore, our study demonstrates that HIF1A is a target for PCa prevention and that TGM2 is a promising prognostic biomarker of early relapse after prostatectomy.

lncRNA HAGLR modulates myocardial ischemia–reperfusion injury in mice through regulating miR-133a-3p/MAPK1 axis

Acute myocardial infarction is one of the leading causes of morbidity worldwide, but the underlying mechanism responsible for myocardial ischemia–reperfusion (I/R) injury remains elusive. lncRNA plays roles in inflammatory response, cell apoptosis and regulation of myocardial ischemia. However, whether lncRNA HAGLR could regulate myocardial I/R injury and the molecular mechanism need to be further investigated. lncRNA has been shown to bind to miRNAs and compete with endogenous RNAs. miR-133a-3p has been shown to regulate cardiomyocyte apoptosis and ischemic myocardial injury. In this work, it has shown that knockdown of HAGLR could suppress inflammatory response and cell apoptosis induced by I/R and, thus, alleviate myocardial I/R injury. HAGLR promoted myocardial I/R injury by inhibiting miR-133a-3p to promote MAPK1 expression.

Docetaxel resistance-derived LINC01085 contributes to the immunotherapy of hormone-independent prostate cancer by activating the STING/MAVS signaling pathway

Acquired docetaxel (doc) resistance, one of the major reasons for unfavorable prognosis in patients with aggressive hormone-independent prostate cancer (HIPC), is a major obstacle for patient treatment. Dysregulation of long non-coding RNAs promotes or suppresses chemoresistance in multiple cancers; however, the specific molecular mechanisms underlying HIPC remain unknown. In this study, we found that the LINC01085, as a tumor-suppressor, which showed significant clinically relevant in HIPC patients with doc-resistance. Mechanistically, in docetaxel-sensitive cells, LINC01085 could specifically bind to both TANK-binding kinase 1 (TBK1) and glycogen synthase kinase 3β (GSK3β), and higher LINC01085 RNA levels could inhibit TBK1 dimerization. Whereas, in doc-resistant cells, lower LINC01085 RNA level lost the strong binding with both, meanwhile, the interaction between TBK1 and GSK3β enhanced which accelerated TBK1 phosphorylation at the Ser-172 site, resulting in decreased expression levels of PD-L1 and NF-κB as well as the secretion of type I/III interferons. Thus, Overexpression of LINC01085 combined with immune checkpoint blockade is an effective strategy for the treatment of HIPC patients.

Hypoxia-Reoxygenation Couples 3βHSD1 Enzyme and Cofactor Upregulation to Facilitate Androgen Biosynthesis and Hormone Therapy Resistance in Prostate Cancer

Androgen deprivation therapy suppresses tumor androgen receptor (AR) signaling by depleting circulating testosterone and is a mainstay treatment for advanced prostate cancer. Despite initial treatment response, castration-resistant prostate cancer nearly always develops and remains driven primarily by the androgen axis. Here we investigated how changes in oxygenation affect androgen synthesis. In prostate cancer cells, chronic hypoxia coupled to reoxygenation resulted in efficient metabolism of androgen precursors to produce androgens and activate AR. Hypoxia induced 3βHSD1, the rate-limiting androgen synthesis regulator, and reoxygenation replenished necessary cofactors, suggesting that hypoxia and reoxygenation both facilitate potent androgen synthesis. The EGLN1/VHL/HIF2α pathway induced 3βHSD1 expression through direct binding of HIF2α to the 5' regulatory region of HSD3B1 to promote transcription. Overexpression of HIF2α facilitated prostate cancer progression, which largely depended on 3βHSD1. Inhibition of HIF2α with the small-molecule PT2399 prevented prostate cancer cell proliferation. These results thus identify HIF2α as a regulator of androgen synthesis and potential therapeutic target in prostate cancer.

SIGNIFICANCE

Hypoxia followed by reoxygenation in prostate cancer drives androgen deprivation therapy resistance via increasing the rate-limiting enzyme and cofactors for androgen synthesis, revealing HIF2α as a therapeutic target to subvert resistance.

LMX1B Activated Circular RNA GFRA1 Modulates the Tumorigenic Properties and Immune Escape of Prostate Cancer

Prostate cancer (PCa) is the most common cancer affecting men, with increasing global mortality and morbidity rates. Despite the progress in the diagnosis and treatment of PCa, patient outcomes remain poor, and novel therapeutic targets for PCa are urgently needed. Recently, circular RNAs (circRNAs) have been studied in-depth as potential biomarkers for many diseases. In this study, circRNA microarrays using four pairs of PCa tissues were utilized to show that circGFRA1 was upregulated in PCa tumor tissues. CircGFRA1 is suggested to play an oncogene role in PCa progression as the silencing of circGFRA1 inhibited the proliferation, migration, and immune escape activity of PCa cells. Furthermore, by utilizing bioinformatics analysis, RIP, RNA pull-down, and luciferase reporter assays, our results showed that LMX1B could bind to the GFRA1 promoter and regulate circGFRA1 expression in PCa cells and circGFRA1 upregulated HECTD1 expression through sponging miR-3064-5p. This novel LMX1B/circGFRA1/miR-3064-5p/HECTD1 axis identified in PCa provides new insights for developing novel therapeutic strategies for PCa.