WNT signalling in prostate cancer

Understanding and overcoming resistance to immunotherapy in genitourinary cancers

The introduction of novel immunotherapies has significantly transformed the treatment landscape of genitourinary (GU) cancers, even becoming the standard of care in some settings. One such type of immunotherapy, immune checkpoint inhibitors (ICIs) like nivolumab, ipilimumab, pembrolizumab, and atezolizumab play a pivotal role by disturbing signaling pathways that limit the immune system's ability to fight tumor cells. Despite the profound impact of these treatments, not all tumors are responsive. Recent research efforts have been focused on understanding how cancer cells manage to evade the immune response and identifying the possible mechanisms behind resistance to immunotherapy. In response, ICIs are being combined with other treatments to reduce resistance and attack cancer cells through multiple cellular pathways. Additionally, novel, targeted strategies are currently being investigated to develop innovative methods of overcoming resistance and treatment failure. This article presents a comprehensive overview of the mechanisms of immunotherapy resistance in GU cancers as currently described in the literature. It explores studies that have identified genetic markers, cytokines, and proteins that may predict resistance or response to immunotherapy. Additionally, we review current efforts to overcome this resistance, which include combination ICIs and sequential therapies, novel insights into the host immune profile, and new targeted therapies. Various approaches that combine immunotherapy with chemotherapy, targeted therapy, vaccines, and radiation have been studied in an effort to more effectively overcome resistance to immunotherapy. While each of these combination therapies has shown some efficacy in clinical trials, a deeper understanding of the immune system's role underscores the potential of novel targeted therapies as a particularly promising area of current research. Currently, several targeted agents are in development, along with the identification of key immune mediators involved in immunotherapy resistance. Further research is necessary to identify predictors of response.

Progress in the development of Modulators targeting Frizzleds

The Frizzleds (FZDs) receptors on the cell surface belong to the class F of G protein-coupled receptors (GPCRs) which are the major receptors of WNT protein that mediates the classical WNT signaling pathway and other non-classical pathways. Besides, the FZDs also play a core role in tissue regeneration and tumor occurrence. With the structure and mechanism of FZDs activation becoming clearer, a series of FZDs modulators (inhibitors and agonists) have been developed, with the hope of bringing benefits to the treatment of cancer and degenerative diseases. Most of the FZDs inhibitors (small molecules, antibodies or designed protein inhibitors) block WNT signaling through binding to the cysteine-rich domain (CRD) of FZDs. Several small molecules impede FZDs activation by targeting to the third intracellular domain or the transmembrane domain of FZDs. However, three small molecules (FZM1.8, SAG1.3 and purmorphamine) activate the FZDs through direct interaction with the transmembrane domain. Another type of FZDs agonists are bivalent or tetravalent antibodies which activate the WNT signaling via inducing FZD-LRP5/6 heterodimerization. In this article, we reviewed the FZDs modulators reported in recent years, summarized the critical molecules' discovery processes and the elucidated relevant structural and pharmacological mechanisms. We believe the summaried molecular mechanisms of the relevant modulators could provide important guidance and reference for the future development of FZD modulators.

Hippo signaling modulation and its biological implications in urological malignancies

Although cancer diagnosis and treatment have rapidly advanced in recent decades, urological malignancies, which have high morbidity and mortality rates, are among the most difficult diseases to treat. The Hippo signaling is an evolutionarily conserved pathway in organ size control and tissue homeostasis maintenance. Its downstream effectors, Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ), are key modulators of numerous physiological and pathological processes. Recent work clearly indicates that Hippo signaling is frequently altered in human urological malignancies. In this review, we discuss the disparate viewpoints on the upstream regulators of YAP/TAZ and their downstream targets and systematically summarize the biological implications. More importantly, we highlight the molecular mechanisms involved in Hippo-YAP signaling to improve our understanding of its role in every stage of prostate cancer, bladder cancer and kidney cancer progression. A better understanding of the biological outcomes of YAP/TAZ modulation will contribute to the establishment of future therapeutic approaches.

Mortalin promotes the evolution of androgen-independent prostate cancer through Wnt/β-catenin signaling pathway

Prostate cancer (PC) is a major global health concern affecting male individuals. Among its variants, androgen-independent prostate cancer exhibits slow progression and lacks effective treatment targets, rendering it insensitive to hormone therapy. Recent reports have highlighted the significance of Mortalin, an important oncogene, in tumor migration and invasion through various signaling pathways. Experimental evidence from in-vivo and in-vitro studies indicate upregulated expression of Mortalin in prostate cancer tissues. Moreover, it has been shown to regulate the epithelial-mesenchymal transition (EMT) process via the Wnt/β-catenin signaling pathway, thereby promoting prostate cancer proliferation and metastasis. These findings suggest that Mortalin may serve as a promising novel immunotherapeutic target for prostate cancer.

Analysis of factors associated with positive surgical margins and the five-year survival rate after prostate cancer resection and predictive modeling

Background

This study analyzed the risk factors associated with positive surgical margins (PSM) and five-year survival after prostate cancer resection to construct a positive margin prediction model.

Methods

We retrospectively analyzed the clinical data of 148 patients treated with prostatectomy. The patients were divided into PSM group and Negative surgical margins (NSM) group. Several parameters were compared between the groups. All patients were followed up for 60 months. The risk factors for PSM and five-year survival were evaluated by univariate analysis, followed by multifactorial dichotomous logistic regression analysis. Finally, ROC curves were plotted for the risk factors to establish a predictive model for PSM after prostate cancer resection.

Results

(1) Serum PSA, percentage of positive puncture stitches, clinical stage, surgical approach, Gleason score on puncture biopsy, and perineural invasion were significantly associated with the risk of PSM (P < 0.05). Serum PSA, perineural invasion, Gleason score on puncture biopsy, and percentage of positive puncture stitches were independent risk factors for PSM. (2) Total prostate-specific antigen (tPSA) by puncture, nutritional status, lymph node metastasis, bone metastasis, and seminal vesicle invasion may be risk factors for five-year survival. Lymph node metastasis and nutritional status were the main risk factors for the five-year survival of patients with prostate cancer. (3) After plotting the ROC curve, the area under the curve (AUC) [AUC: 0.776, 95%, confidence interval (CI): 0.725 to 0.854] was found to be a valid predictor of PSM; the AUC [AUC: 0.664, 95%, confidence interval (CI): 0.576 to 0.753] was also a valid predictor of five-year survival (P < 0.05). (4) The scoring system had a standard error of 0.02 and a cut-off value of 6. It predicted PSM after prostate cancer resection with moderate efficacy.

Conclusions

Serum PSA, perineural invasion, puncture biopsy Gleason score, and percentage of positive puncture stitches were independent risk factors for positive surgical margins (PSM). Also, lymph node metastasis and nutritional status were the main risk factors for the five-year survival of patients with prostate cancer. Overall, the prediction efficacy of this scoring system concerning the risk of PSM after prostate cancer resection was moderate.

Molecular Pathology of Prostate Cancer

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

Bisphenol S enhances the cell proliferation ability of prostate cancer cells by regulating the expression of SDS

Recent times have witnessed an increase in both incidence and mortality rates of prostate cancer. While some individuals with localized or metastatic cancer may progress slowly with a lower mortality risk, those with intermediate or high-risk cancer often face a higher likelihood of death, despite treatment. Bisphenol A (BPA) has been linked to various cancers, including prostate and breast cancer, yet the relationship between bisphenol S (BPS) and human health remains underexplored. In our study, we employed ssGSEA analysis to evaluate the BPS-associated score in a prostate cancer cohort. Additionally, differential expression analysis identified BPS-related genes within the same group. Through COX and LASSO regression analyses, we developed and validated a BPS-related risk model using ROC curve and survival analyses. A nomogram, integrating clinical characteristics with this risk model, was established for improved predictive accuracy, further substantiated by calibration curve validation. Molecular docking analysis suggested potential binding between SDS and BPS. We also conducted cell proliferation assays on C4-2 and LNCaP prostate cancer cells, revealing increased cell growth at a BPS concentration of 10-7 M, as evidenced by CCK8 and EdU assays. In summary, our findings shed light on the BPS-prostate cancer linkage, identifying BPS-associated genes, establishing a validated risk model, exploring SDS-BPS binding potential, and assessing BPS's effect on prostate cancer cell growth. These insights underscore the need for further investigation into BPS and its impact on human diseases.

UBE2N promotes cell viability and glycolysis by promoting Axin1 ubiquitination in prostate cancer cells

BACKGROUND

Ubiquitin-conjugating enzyme E2 N (UBE2N) is recognized in the progression of some cancers; however, little research has been conducted to describe its role in prostate cancer. The purpose of this paper is to explore the function and mechanism of UBE2N in prostate cancer cells.

METHODS

UBE2N expression was detected in Cancer Genome Atlas Prostate Adenocarcinoma (TCGA-PRAD) data, prostate cancer tissue microarrays, and prostate cancer cell lines, respectively. UBE2N knockdown or overexpression was used to analyze its role in cell viability and glycolysis of prostate cancer cells and tumor growth. XAV939 or Axin1 overexpression was co-treated with UBE2N overexpression to detect the involvement of the Wnt/β-catenin signaling and Axin1 in the UBE2N function. UBE2N interacting with Axin1 was analyzed by co-immunoprecipitation assay.

RESULTS

UBE2N was upregulated in prostate cancer and the UBE2N-high expression correlated with the poor prognosis of prostate cancer. UBE2N knockdown inhibited cell viability and glycolysis in prostate cancer cells and restricted tumor formation in tumor-bearing mice. Wnt/β-catenin inhibition and Axin1 overexpression reversed the promoting viability and glycolysis function of UBE2N. UBE2N promoted Axin1 ubiquitination and decreased Axin1 protein level.

MiR26a reverses enzalutamide resistance in a bone-tumor targeted system with an enhanced effect on bone metastatic CRPC

Resistance to androgen receptor (AR) inhibitors, including enzalutamide (Enz), as well as bone metastasis, are major challenges for castration-resistant prostate cancer (CRPC) treatment. In this study, we identified that miR26a can restore Enz sensitivity and inhibit bone metastatic CRPC. To achieve the highest combination effect of miR26a and Enz, we developed a cancer-targeted nano-system (Bm@PT/Enz-miR26a) using bone marrow mesenchymal stem cell (BMSC) membrane and T140 peptide to co-deliver Enz and miR26a. The in vitro/in vivo results demonstrated that miR26a can reverse Enz resistance and synergistically shrink tumor growth, invasion, and metastasis (especially secondary metastasis) in both subcutaneous and bone metastatic CRPC mouse models. We also found that the EZH2/SFRP1/WNT5A axis may be involved in this role. These findings open new avenues for treating bone metastatic and Enz-resistant CRPC.

Nuclear receptor NURR1 functions to promote stemness and epithelial-mesenchymal transition in prostate cancer via its targeting of Wnt/β-catenin signaling pathway

Dysregulated activation of Wnt/β-catenin signaling pathway is a frequent or common event during advanced progression of multiple cancers. With this signaling activation, it enhances their tumorigenic growth and facilitates metastasis and therapy resistance. Advances show that this signaling pathway can play dual regulatory roles in the control of cellular processes epithelial-mesenchymal transition (EMT) and cancer stemness in cancer progression. Aberrant activation of Wnt/β-catenin signaling pathway is shown to be common in prostate cancer and also castration-resistant prostate cancer (CRPC). However, the transcriptional regulators of this pathway in prostate cancer are still not well characterized. NURR1 (NR4A2) is an orphan nuclear receptor and plays an important role in the development of dopaminergic neurons. Previously, we have shown that NURR1 exhibits an upregulation in isolated prostate cancer stem-like cells (PCSCs) and a xenograft model of CRPC. In this study, we further confirmed that NURR1 exhibited an upregulation in prostate cancer and also enhanced expression in prostate cancer cell lines. Functional and molecular analyses showed that NURR1 could act to promote both in vitro (cancer stemness and EMT) and also in vivo oncogenic growth of prostate cancer cells (metastasis and castration resistance) via its direct transactivation of CTNNB1 (β-catenin) and activation of β-catenin to mediate the activation of Wnt/β-catenin signaling pathway. Moreover, we also demonstrated that NURR1 activity in prostate cancer cells could be modulated by small molecules, implicating that NURR1 could be a potential therapeutic target for advanced prostate cancer management.

Deciphering cellular and molecular mechanism of MUC13 mucin involved in cancer cell plasticity and drug resistance

There has been a surge of interest in recent years in understanding the intricate mechanisms underlying cancer progression and treatment resistance. One molecule that has recently emerged in these mechanisms is MUC13 mucin, a transmembrane glycoprotein. Researchers have begun to unravel the molecular complexity of MUC13 and its impact on cancer biology. Studies have shown that MUC13 overexpression can disrupt normal cellular polarity, leading to the acquisition of malignant traits. Furthermore, MUC13 has been associated with increased cancer plasticity, allowing cells to undergo epithelial-mesenchymal transition (EMT) and metastasize. Notably, MUC13 has also been implicated in the development of chemoresistance, rendering cancer cells less responsive to traditional treatment options. Understanding the precise role of MUC13 in cellular plasticity, and chemoresistance could pave the way for the development of targeted therapies to combat cancer progression and enhance treatment efficacy.

Inhibition of the Cyclin K-CDK12 complex induces DNA damage and increases the effect of androgen deprivation therapy in prostate cancer

Androgen deprivation therapy (ADT) is the mainstay of the current first-line treatment concepts for patients with advanced prostate carcinoma (PCa). However, due to treatment failure and recurrence investigation of new targeted therapeutics is urgently needed. In this study, we investigated the suitability of the Cyclin K-CDK12 complex as a novel therapeutic approach in PCa using the new covalent CDK12/13 inhibitor THZ531. Here we show that THZ531 impairs cellular proliferation, induces apoptosis, and decreases the expression of selected DNA repair genes in PCa cell lines, which is associated with an increasing extent of DNA damage. Furthermore, combination of THZ531 and ADT leads to an increase in these anti-tumoral effects in androgen-sensitive PCa cells. The anti-proliferative and pro-apoptotic activity of THZ531 in combination with ADT was validated in an ex vivo PCa tissue culture model. In a retrospective immunohistochemical analysis of 300 clinical tissue samples we show that Cyclin K (CycK) but not CDK12 expression correlates with a more aggressive type of PCa. In conclusion, this study demonstrates the clinical relevance of the CycK-CDK12 complex as a promising target for combinational therapy with ADT in PCa and its importance as a prognostic biomarker for patients with PCa.

Investigation of iso-propylchaetominine anticancer activity on apoptosis, cell cycle and Wnt signaling pathway in different cancer models

Dysregulation of the Wnt signaling pathway contributes to the development of many cancer types. Natural compounds produced with biotechnological systems have been the focus of research for being a new drug candidate both with unlimited resources and cost-effective production. In this study, it was aimed to reveal the effects of isopropylchaetominine on cytotoxic, cytostatic, apoptotic and Wnt signaling pathways in brain, pancreatic and prostate cancer. The IC50 values of isopropylchaetominine in U-87 MG, PANC1, PC3 and LNCaP cells were calculated as 91.94 μM, 41.68 μM, 54.54 μM and 7.86 μM in 72nd h, respectively. The metabolite arrests the cell cycle in G0/G1 phase in each cancer cells. Iso-propylchaetominine induced a 4.3-fold and 1.9-fold increase in apoptosis in PC3 and PANC1 cells, respectively. The toxicity of isopropylchaetominine in healthy fibroblast cells was assessed using the annexin V method, and no significant apoptotic activity was observed between the groups treated with the active substance and untreated. In U-87 MG, PANC1, PC3, and LNCaP cells under treatment with isopropylchaetominin, the expression levels of DKK3, TLE1, AES, DKK1, FRZB, DAB2, AXIN1/2, PPARD, SFRP4, APC and SOX17 tumor suppressor genes increased significantly. Decreases in expression of Wnt1, Wnt2, Wnt3, Wnt4, Wnt5, Wnt6, Wnt10, Wnt11, FRZ2, FRZ3, FRZ7, TCF7L1, BCL9, PYGO, CCND2, c-MYC, WISP1 and CTNNB1 oncogenic genes were detected. All these result shows that isopropylchaetominine can present promising new treatment strategy in different cancer types.

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.

Molecular biomarkers in prostate cancer tumorigenesis and clinical relevance

Prostate cancer (PCa) is the second most frequent type of cancer in men and assessing circulating tumor cells (CTCs) by liquid biopsy is a promising tool to help in cancer early detection, staging, risk of recurrence evaluation, treatment prediction and monitoring. Blood-based liquid biopsy approaches enable the enrichment, detection and characterization of CTCs by biomarker analysis. Hence, comprehending the molecular markers, their role on each stage of cancer development and progression is essential to provide information that can help in future implementation of these biomarkers in clinical assistance. In this review, we studied the molecular markers most associated with PCa CTCs to better understand their function on tumorigenesis and metastatic cascade, the methodologies utilized to analyze these biomarkers and their clinical significance, in order to summarize the available information to guide researchers in their investigations, new hypothesis formulation and target choice for the development of new diagnostic and treatment tools.

Case Series of Men with the Germline APC I1307K variant and Treatment-Emergent Neuroendocrine Prostate Cancer

INTRODUCTION

Somatic mutations in the Wnt signaling gene Adenomatous Polyposis Coli (APC) promote metastatic prostate cancer (PCa) progression. Less is known regarding the impact of germline APC mutations on PCa outcomes. We sought to investigate the prevalence of aggressive variant PCa (AVPC) and treatment-emergent neuroendocrine PCa (t-NEPC) in patients with the germline APC I1307K variant, an alteration found in 7% of Ashkenazi Jewish men.

MATERIALS AND METHODS

We report a retrospective cohort study comparing patients with PCa and either APC I1307K germline mutation, APC somatic mutations, or unselected patients. Proportions of patients with AVPC among all the cases were estimated along with 95% Clopper-Pearson exact confidence intervals (CI). Odds ratios with 95% CI were provided for the prevalence of t-NEPC and AVPC in patients with germline APC I1307K compared to patients with frameshift alterations in APC.

RESULTS

From 2016-2022, 18 patients with PCa at 3 institutions with the germline APC (I1307K) mutation were identified. Clinically-defined AVPC was found in 8 of the 15 cases with metastatic disease (53%; 95% CI: 26%-79%). Combined somatic alterations in two or more of RB1, TP53 or PTEN (molecularly-defined AVPC) were found in 5/18 cases (28%; 95% CI: 10%-54%). When compared to 20 patients with APC somatic frameshift mutations, patients with the germline APC I1307K variant had a significantly increased risk of AVPC (OR 7.2; 95% CI 1.27, 40.68).

CONCLUSION

PCa that develops in the presence of the germline APC I1307K mutation appear to be enriched for clinically-defined and molecularly-defined AVPC and in particular, for t-NEPC.

Decoding the basis of histological variation in human cancer

Molecular abnormalities that shape human neoplasms dissociate their phenotypic landscape from that of the healthy counterpart. Through the lens of a microscope, tumour pathology optically captures such aberrations projected onto a tissue slide and has categorized human epithelial neoplasms into distinct histological subtypes based on the diverse morphogenetic and molecular programmes that they manifest. Tumour histology often reflects tumour aggressiveness, patient prognosis and therapeutic vulnerability, and thus has been used as a de facto diagnostic tool and for making clinical decisions. However, it remains elusive how the diverse histological subtypes arise and translate into pleiotropic biological phenotypes. Molecular analysis of clinical tumour tissues and their culture, including patient-derived organoids, and add-back genetic reconstruction of tumorigenic pathways using gene engineering in culture models and rodents further elucidated molecular mechanisms that underlie morphological variations. Such mechanisms include genetic mutations and epigenetic alterations in cellular identity codes that erode hard-wired morphological programmes and histologically digress tumours from the native tissues. Interestingly, tumours acquire the ability to grow independently of the niche-driven stem cell ecosystem along with these morphological alterations, providing a biological rationale for histological diversification during tumorigenesis. This Review comprehensively summarizes our current understanding of such plasticity in the histological and lineage commitment fostered cooperatively by molecular alterations and the tumour environment, and describes basic and clinical implications for future cancer therapy.

CCT6A dysregulation in surgical prostate cancer patients: association with disease features, treatment information, and prognosis

OBJECTIVE

Chaperonin-containing tailless complex polypeptide 1 subunit 6A (CCT6A) involves several solid cancers' development and progression, while its clinical utility in prostate cancer management is rarely revealed. Consequently, the present study intended to investigate the linkage of CCT6A with disease features, treatment information, and prognosis of surgical prostate cancer patients.

METHODS

CCT6A in 220 surgical prostate cancer patients was determined via immunohistochemistry. Additionally, survival analyses on data from the public databases were performed to validate the prognostic value of CCT6A further.

RESULTS

CCT6A expression was upregulated in tumor tissue than in adjacent tissue (P < 0.001). Increased CCT6A was related to elevated Gleason score (P < 0.001) and pathological T stage (P = 0.029). CCT6A was increased in patients with positive surgical margin status (vs. negative) (P = 0.029) and patients with adjuvant external-beam radiation therapy (vs. no) (P = 0.001). Concerning the prognostic value, high tumor CCT6A was linked with shortened disease-free survival (DFS) (P = 0.009), which was also validated through further Cox's proportional hazard regression model analyses (hazard ratio: 2.695, 95% CI: 1.086-6.683, P = 0.032), whereas CCT6A was not correlated with overall survival (OS) (P > 0.050). Additionally, the Gene Expression Profiling Interactive Analysis database indicated that high tumor CCT6A was related to shortened DFS (P = 0.036), but it was not associated with OS (P > 0.050); meanwhile, the Human Protein Atlas database suggested that high tumor CCT6A was linked with reduced OS (P = 0.048).

CONCLUSION

Tumor CCT6A high expression correlates with the elevated Gleason score, pathological T stage, and shortened DFS in surgical prostate cancer patients.

A plasma membrane-associated form of the androgen receptor enhances nuclear androgen signaling in osteoblasts and prostate cancer cells

Androgen binding to the androgen receptor (AR) in the cytoplasm induces the AR to translocate to the nucleus, where it regulates the expression of target genes. Here, we found that androgens rapidly activated a plasma membrane-associated signaling node that enhanced nuclear AR functions. In murine primary osteoblasts, dihydrotestosterone (DHT) binding to a membrane-associated form of AR stimulated plasma membrane-associated protein kinase G type 2 (PKG2), leading to the activation of multiple kinases, including ERK. Phosphorylation of AR at Ser515 by ERK increased the nuclear accumulation and binding of AR to the promoter of Ctnnb1, which encodes the transcription factor β-catenin. In male mouse osteoblasts and human prostate cancer cells, DHT induced the expression of Ctnnb1 and CTNN1B, respectively, as well as β-catenin target genes, stimulating the proliferation, survival, and differentiation of osteoblasts and the proliferation of prostate cancer cells in a PKG2-dependent fashion. Because β-catenin is a master regulator of skeletal homeostasis, these results explain the reported male-specific osteoporotic phenotype of mice lacking PKG2 in osteoblasts and imply that PKG2-dependent AR signaling is essential for maintaining bone mass in vivo. Our results suggest that widely used pharmacological PKG activators, such as sildenafil, could be beneficial for male and estrogen-deficient female patients with osteoporosis but detrimental in patients with prostate cancer.

Divergent immune microenvironments in two tumor nodules from a patient with mismatch repair-deficient prostate cancer

Patients with prostate cancer (PC) generally do not respond favorably to immune checkpoint inhibitors, which may be due to a low abundance of tumor-infiltrating lymphocytes even when mutational load is high. Here, we identified a patient who presented with high-grade primary prostate cancer with two adjacent tumor nodules. While both nodules were mismatch repair-deficient (MMRd), exhibited pathogenic MSH2 and MSH6 alterations, had a high tumor mutational burden (TMB), and demonstrated high microsatellite instability (MSI), they had markedly distinct immune phenotypes. The first displayed a dense infiltrate of lymphocytes ("hot nodule"), while the second displayed significantly fewer infiltrating lymphocytes ("cold nodule"). Whole-exome DNA analysis found that both nodules shared many identical mutations, indicating that they were derived from a single clone. However, the cold nodule appeared to be sub-clonal relative to the hot nodule, suggesting divergent evolution of the cold nodule from the hot nodule. Whole-transcriptome RNA analysis found that the cold nodule demonstrated lower expression of genes related to antigen presentation (HLA) and, paradoxically, classical tumor immune tolerance markers such as PD-L1 (CD274) and CTLA-4. Immune cell deconvolution suggested that the hot nodule was enriched not only in CD8+ and CD4 + T lymphocytes, but also in M1 macrophages, activated NK cells, and γδ T cells compared to the cold nodule. This case highlights that MMRd/TMB-high PC can evolve to minimize an anti-tumor immune response, and nominates downregulation of antigen presentation machinery (HLA loss) as a potential mechanism of adaptive immune evasion in PC.

m6A-Mediated Upregulation of lncRNA CHASERR Promotes the Progression of Glioma by Modulating the miR-6893-3p/TRIM14 Axis

Long noncoding RNAs (lncRNAs) play crucial roles in tumor progression and are dysregulated in glioma. However, the functional roles of lncRNAs in glioma remain largely unknown. In this study, we utilized the TCGA (the Cancer Genome Atlas database) and GEPIA2 (Gene Expression Profiling Interactive Analysis 2) databases and observed the overexpression of lncRNA CHASERR in glioma tissues. We subsequently investigated this phenomenon in glioma cell lines. The effects of lncRNA CHASERR on glioma proliferation, migration, and invasion were analyzed using in vitro and in vivo experiments. Additionally, the regulatory mechanisms among PTEN/p-Akt/mTOR and Wnt/β-catenin, lncRNA CHASERR, Micro-RNA-6893-3p(miR-6893-3p), and tripartite motif containing14 (TRIM14) were investigated via bioinformatics analyses, quantitative real-time PCR (qRT-PCR), western blot (WB), RNA immunoprecipitation (RIP), dual luciferase reporter assay, fluorescence in situ hybridization (FISH), and RNA sequencing assays. RIP and RT-qRCR were used to analyze the regulatory effect of N6-methyladenosine(m6A) on the aberrantly expressed lncRNA CHASERR. High lncRNA CHASERR expression was observed in glioma tissues and was associated with unfavorable prognosis in glioma patients. Further functional assays showed that lncRNA CHASERR regulates glioma growth and metastasis in vitro and in vivo. Mechanistically, lncRNA CHASERR sponged miR-6893-3p to upregulate TRIM14 expression, thereby facilitating glioma progression. Additionally, the activation of PTEN/p-Akt/mTOR and Wnt/β-catenin pathways by lncRNA CHASERR, miR-6893-3p, and TRIM14 was found to regulate glioma progression. Moreover, the upregulation of lncRNA CHASERR was observed in response to N6-methyladenosine modification, which was facilitated by METTL3/YTHDF1-mediated RNA transcripts. This study elucidates the m6A/lncRNACHASERR/miR-6893-3p/TRIM14 pathway that contributes to glioma progression and underscores the potential of lncRNA CHASERR as a novel prognostic indicator and therapeutic target for glioma.

STEAP4 modulates cell proliferation and oxidative stress in benign prostatic hyperplasia

Benign prostatic hyperplasia (BPH) is a quite common chronic disease plagued elderly men and its etiology remains unclear. It was reported that the six-transmembrane epithelial antigen of prostate 4 (STEAP4) could modulate cell proliferation/apoptosis ratio and oxidative stress in cancers. Our current study aimed to explore the expression, biological function, and underlying mechanism of STEAP4 in BPH progress. Human prostate tissues and cell lines were utilized. qRT-PCR and immunofluorescence staining were employed. STEAP4 knockdown (STEAP4-KD) or STEAP4 overexpression (STEAP4-OE) cell models were established. Cell proliferation, cell cycle, apoptosis, and reactive oxygen species (ROS) were determined by cell counting kit-8 (CCK-8) assay and flow cytometry. Apoptosis-related proteins and antioxidant enzymes were identified by Western Blot. In addition, the epithelial-mesenchymal transition (EMT) process and fibrosis biomarker (collagen I and α-SMA) were analyzed. It was indicated that STEAP4 was mainly located in the prostate epithelium and upregulated in BPH tissues. STEAP4 deficiency induced apoptosis and inhibited cell survival, but had no effect on the cell cycle, fibrosis, and EMT process. In addition, ROS changes were observed in the STEAP4-KD model. Consistently, overproduction of STEAP4 suppressed apoptosis and promoted cell proliferation, as well as facilitated ROS production. We further examined AKT / mTOR, p38MAPK / p-p38MAPK, and WNT/ β-Catenin signaling pathway and demonstrated that STEAP4 regulated the proliferation and apoptosis of prostate cells through AKT / mTOR signaling, rather than p38MAPK / p-p38MAPK and WNT/ β-Catenin pathways. Furthermore, activating AKT / mTOR signaling with SC79 significantly reversed apoptosis triggered by STEAP4 deficiency, whereas suppressing AKT / mTOR signaling with MK2206 reduced the increase of cell viability triggered by STEAP4 overproduction. Our original data demonstrated that STEAP4 is crucial in the onset and progression of prostate hyperplasia and may become a new target for the treatment of BPH.

Androgen-repressed lncRNA LINC01126 drives castration-resistant prostate cancer by regulating the switch between O-GlcNAcylation and phosphorylation of androgen receptor

BACKGROUND

Prostate cancer (PCa) initially shows satisfactory response to therapies targeting the androgen receptor (AR). However, progression to a castration-resistant stage indicates poor prognosis in PCa patients. AR signalling still plays a central role in most castration-resistant prostate cancers (CRPC). Therefore, unveiling the mechanisms of AR reactivation under androgen-deprived conditions is imperative to discover novel therapeutic targets for CRPC.

METHODS

Using an integrative analysis of the transcriptomics of three independent PCa cohorts and a published landscape of AR-regulated long non-coding RNA (lncRNA), lncRNA LINC01126 was selected as a candidate gene that could drive CRPC progression for further study. Quantitative reverse transcription polymerase chain reaction, in situ hybridisation (ISH) and fluorescent ISH were performed to detect LINC01126 in PCa tissues and cells. The functional role and mechanism of LINC01126 were further investigated using in vitro and in vivo gain and loss of function assays.

RESULTS

LINC01126, identified as an AR-repressed lncRNA, was significantly upregulated after AR-targeted therapies. In addition, we found that LINC01126 was upregulated in CRPC and was associated with poor prognosis. We also proved that LINC01126 stabilised AR protein and enhanced AR nuclear translocation and transactivation by promoting the transition from O-GlcNAcylation at threonine 80 to phosphorylation at serine 81 (S81) within the AR protein. Mechanism analysis revealed that LINC01126 facilitates the interaction of CDK9 with AR and impedes the binding of O-linked N-acetylglucosamine (O-GlcNAc) transferase to AR. Consequently, LINC01126 expression was sufficient to activate AR signalling without androgen. LINC01126 overexpression increased, whereas LINC01126 knockdown decreased castration resistance traits in PCa cells in vitro and in vivo. Furthermore, our data showed that LINC01126-targeting antisense oligonucleotides (ASO) substantially inhibited CRPC cells in vitro.

CONCLUSIONS

Our research expands the functions of AR-regulated lncRNA in sustaining androgen-independent AR activity and promoting CRPC progression and reveals that LINC01126 may be a new therapeutic target for PCa.

Hyperoside Inhibits RNF8-mediated Nuclear Translocation of β-catenin to Repress PD-L1 Expression and Prostate Cancer

BACKGROUND

Hyperoside is a flavonol glycoside isolated from Hypericum perforatum L. that has inhibitory effects on cancer cells; however, its effects on prostate cancer (PCa) remain unclear. Therefore, we studied the anti-PCa effects of hyperoside and its underlying mechanisms in vitro and in vivo.

AIM

This study aimed to explore the mechanism of hyperoside in anti-PCa.

METHODS

3-(4,5-Dimethyl-2-Thiazolyl)-2,5-Diphenyl Tetrazolium Bromide (MTT), transwell, and flow cytometry assays were used to detect PCa cell growth, invasion, and cell apoptosis. Immunoblot analysis, immunofluorescence, immunoprecipitation, and quantitative real-time PCR (qRT-PCR) were used to analyze the antitumor mechanism of hyperoside.

RESULTS

Hyperoside inhibited PCa cell growth, invasion, and cell cycle and induced cell apoptosis. Furthermore, RING finger protein 8 (RNF8), an E3 ligase that assembles K63 polyubiquitination chains, was predicted to be a direct target of hyperoside and was downregulated by hyperoside. Downregulation of RNF8 by hyperoside impeded the nuclear translocation of β-catenin and disrupted the Wnt/β-catenin pathway, which reduced the expression of the target genes c-myc, cyclin D1, and programmed death ligand 1 (PD-L1). Decreased PD-L1 levels contributed to induced immunity in Jurkat cells in vitro. Finally, in vivo studies demonstrated that hyperoside significantly reduced tumor size, inhibited PD-L1 and RNF8 expression, and induced apoptosis in tumor tissues of a subcutaneous mouse model.

CONCLUSION

Hyperoside exerts its anti-PCa effect by reducing RNF8 protein, inhibiting nuclear translocation of β-catenin, and disrupting the Wnt/β-catenin pathway, in turn reducing the expression of PD-L1 and improving Jurkat cell immunity.

Resistin Induces Migration and Invasion in PC3 Prostate Cancer Cells: Role of Extracellular Vesicles

Resistin is an adipokine with metabolic and inflammatory functions. Epidemiological and translational studies report that an increase in plasma levels and tissue expression of resistin increases the aggressiveness of prostate tumor cells. Extracellular vesicles (EVs) are secreted constitutively and induced by cytokines, growth factors, and calcium and are found in multiple biological fluids such as saliva, serum, semen, and urine. In particular, EVs have been shown to promote tumor progression through the induction of proliferation, growth, angiogenesis, resistance to chemotherapy, and metastasis. However, the role of resistin in the migration, invasion, and secretion of EVs in invasive prostate tumor cells remains to be studied. In the present study, we demonstrate that resistin induces increased migration and invasion in PC3 cells. In addition, these phenomena are accompanied by increased p-FAK levels and increased secretion of MMP-2 and MMP-9 in resistin-treated PC3 cells. Interestingly, EVs isolated from supernatants of PC3 cells treated with resistin induce an increase in migration and invasion accompanied by high MMP-2 and MMP-9 secretion in an autocrine stimulation model. In summary, our data for the first time demonstrate that resistin induces migration and invasion, partly through the secretion of EVs with pro-invasive characteristics in PC3 cells.

BMP signaling in cancer stemness and differentiation

The BMP (Bone morphogenetic protein) signaling pathway plays a central role in metazoan biology, intricately shaping embryonic development, maintaining tissue homeostasis, and influencing disease progression. In the context of cancer, BMP signaling exhibits context-dependent dynamics, spanning from tumor suppression to promotion. Cancer stem cells (CSCs), a modest subset of neoplastic cells with stem-like attributes, exert substantial influence by steering tumor growth, orchestrating therapy resistance, and contributing to relapse. A comprehensive grasp of the intricate interplay between CSCs and their microenvironment is pivotal for effective therapeutic strategies. Among the web of signaling pathways orchestrating cellular dynamics within CSCs, BMP signaling emerges as a vital conductor, overseeing CSC self-renewal, differentiation dynamics, and the intricate symphony within the tumor microenvironment. Moreover, BMP signaling's influence in cancer extends beyond CSCs, intricately regulating cellular migration, invasion, and metastasis. This multifaceted role underscores the imperative of comprehending BMP signaling's contributions to cancer, serving as the foundation for crafting precise therapies to navigate multifaceted challenges posed not only by CSCs but also by various dimensions of cancer progression. This article succinctly encapsulates the diverse roles of the BMP signaling pathway across different cancers, spanning glioblastoma multiforme (GBM), diffuse intrinsic pontine glioma (DIPG), colorectal cancer, acute myeloid leukemia (AML), lung cancer, prostate cancer, and osteosarcoma. It underscores the necessity of unraveling underlying mechanisms and molecular interactions. By delving into the intricate tapestry of BMP signaling's engagement in cancers, researchers pave the way for meticulously tailored therapies, adroitly leveraging its dualistic aspects-whether as a suppressor or promoter-to effectively counter the relentless march of tumor progression.

Molecular Efficacy of Gnetin C as Dual-Targeted Therapy for Castrate-Resistant Prostate Cancer

SCOPE

Resistance of castrate-resistant prostate cancer (CRPC) to enzalutamide (Enz) involves the expression of constitutively active androgen receptor splice variant (AR-V7). In addition to altered AR pathways, CRPC is characterized by "non-AR-driven" signaling, which includes an overexpression of metastasis-associated protein 1 (MTA1). Combining natural compounds with anticancer drugs may enhance drug effectiveness while reducing adverse effects. In this study, the in vitro and in vivo anticancer effects of Gnetin C (GnC) alone and in combination with Enz against CRPC are examined.

METHODS AND RESULTS

The effects of GnC alone and in combination with Enz are assessed by cell viability, clonogenic survival, cell migration, and AR and MTA1 expression using 22Rv1 cells. The tumor growth in vivo is assessed by bioluminescent imaging, western blots, RT-PCR, and IHC. GnC alone and in combined treatment inhibit cell viability, clonogenic survival and migration, and AR and MTA1 expression in 22Rv1 cells. The underlying AR- and MTA1-targeted anticancer mechanisms of treatments in vivo involve inhibition of proliferation and angiogenesis, and induction of apoptosis.

CONCLUSION

The findings demonstrate that GnC alone and GnC combined with Enz effectively inhibits AR- and MTA1-promoted tumor-progression in advanced CRPC, which indicates its potential as a novel therapeutic approach for CRPC.

Repurposing synthetic and natural derivatives induces apoptosis in an orthotopic glioma-induced xenograft model by modulating WNT/β-catenin signaling

BACKGROUND

Glioblastomas arise from multistep tumorigenesis of the glial cells. Despite the current state-of-art treatment, tumor recurrence is inevitable. Among the innovations blooming up against glioblastoma, drug repurposing could provide profound premises for treatment enhancement. While considering this strategy, the efficacy of the repurposed drugs as monotherapies were not up to par; hence, the focus has now shifted to investigate the multidrug combinations.

AIM

To investigate the efficacy of a quadruple-combinatorial treatment comprising temozolomide along with chloroquine, naringenin, and phloroglucinol in an orthotopic glioma-induced xenograft model.

METHODS

Antiproliferative effect of the drugs was assessed by immunostaining. The expression profiles of WNT/β-catenin and apoptotic markers were evaluated by qRT-PCR, immunoblotting, and ELISA. Patterns of mitochondrial depolarization was determined by flow cytometry. TUNEL assay was performed to affirm apoptosis induction. In vivo drug detection study was carried out by ESI-Q-TOF MS analysis.

RESULTS

The quadruple-drug treatment had significantly hampered glioma proliferation and had induced apoptosis by modulating the WNT/β-catenin signaling. Interestingly, the induction of apoptosis was associated with mitochondrial depolarization. The quadruple-drug cocktail had breached the blood-brain barrier and was detected in the brain tissue and plasma samples.

CONCLUSION

The quadruple-drug combination served as a promising adjuvant therapy to combat glioblastoma lethality in vivo and can be probed for translation from bench to bedside.

Caspase-Linked Programmed Cell Death in Prostate Cancer: From Apoptosis, Necroptosis, and Pyroptosis to PANoptosis

Prostate cancer (PCa) is a complex disease and the cause of one of the highest cancer-related mortalities in men worldwide. Annually, more than 1.2 million new cases are diagnosed globally, accounting for 7% of newly diagnosed cancers in men. Programmed cell death (PCD) plays an essential role in removing infected, functionally dispensable, or potentially neoplastic cells. Apoptosis is the canonical form of PCD with no inflammatory responses elicited, and the close relationship between apoptosis and PCa has been well studied. Necroptosis and pyroptosis are two lytic forms of PCD that result in the release of intracellular contents, which induce inflammatory responses. An increasing number of studies have confirmed that necroptosis and pyroptosis are also closely related to the occurrence and progression of PCa. Recently, a novel form of PCD named PANoptosis, which is a combination of apoptosis, necroptosis, and pyroptosis, revealed the attached connection among them and may be a promising target for PCa. Apoptosis, necroptosis, pyroptosis, and PANoptosis are good examples to better understand the mechanism underlying PCD in PCa. This review aims to summarize the emerging roles and therapeutic potential of apoptosis, necroptosis, pyroptosis, and PANoptosis in PCa.

Effects of Dickkopf-1 (DKK-1) on Prostate Cancer Growth and Bone Metastasis

Osteoblastic bone metastases are commonly detected in patients with advanced prostate cancer (PCa) and are associated with an increased mortality rate. Dickkopf-1 (DKK-1) antagonizes canonical WNT/β-catenin signaling and plays a complex role in bone metastases. We explored the function of cancer cell-specific DKK-1 in PCa growth, metastasis, and cancer-bone interactions using the osteoblastic canine PCa cell line, Probasco. Probasco or Probasco + DKK-1 (cells transduced with human DKK-1) were injected into the tibia or left cardiac ventricle of athymic nude mice. Bone metastases were detected by bioluminescent imaging in vivo and evaluated by micro-computed tomography and histopathology. Cancer cell proliferation, migration, gene/protein expression, and their impact on primary murine osteoblasts and osteoclasts, were evaluated in vitro. DKK-1 increased cancer growth and stimulated cell migration independent of canonical WNT signaling. Enhanced cancer progression by DKK-1 was associated with increased cell proliferation, up-regulation of NF-kB/p65 signaling, inhibition of caspase-dependent apoptosis by down-regulation of non-canonical WNT/JNK signaling, and increased expression of epithelial-to-mesenchymal transition genes. In addition, DKK-1 attenuated the osteoblastic activity of Probasco cells, and bone metastases had decreased cancer-induced intramedullary woven bone formation. Decreased bone formation might be due to the inhibition of osteoblast differentiation and stimulation of osteoclast activity through a decrease in the OPG/RANKL ratio in the bone microenvironment. The present study indicated that the cancer-promoting role of DKK-1 in PCa bone metastases was associated with increased growth of bone metastases, reduced bone induction, and altered signaling through the canonical WNT-independent pathway. DKK-1 could be a promising therapeutic target for PCa.

HIRA-mediated loading of histone variant H3.3 controls androgen-induced transcription by regulation of AR/BRD4 complex assembly at enhancers

Incorporation of histone variant H3.3 comprises active territories of chromatin. Exploring the function of H3.3 in prostate cancer (PC), we found that knockout (KO) of H3.3 chaperone HIRA suppresses PC growth in vitro and in xenograft settings, deregulates androgen-induced gene expression and alters androgen receptor (AR) binding within enhancers of target genes. H3.3 affects transcription in multiple ways, including activation of p300 by phosphorylated H3.3 at Ser-31 (H3.3S31Ph), which results in H3K27 acetylation (H3K27Ac) at enhancers. In turn, H3K27Ac recruits bromodomain protein BRD4 for enhancer-promoter interaction and transcription activation. We observed that HIRA KO reduces H3.3 incorporation, diminishes H3.3S31Ph and H3K27Ac, modifies recruitment of BRD4. These results suggest that H3.3-enriched enhancer chromatin serves as a platform for H3K27Ac-mediated BRD4 recruitment, which interacts with and retains AR at enhancers, resulting in transcription reprogramming. In addition, HIRA KO deregulates glucocorticoid- (GR) driven transcription of genes co-regulated by AR and GR, suggesting a common H3.3/HIRA-dependent mechanism of nuclear receptors function. Expression of HIRA complex proteins is increased in PC compared with normal prostate tissue, especially in high-risk PC groups, and is associated with a negative prognosis. Collectively, our results demonstrate function of HIRA-dependent H3.3 pathway in regulation of nuclear receptors activity.

Mechanism of RhoA regulating benign prostatic hyperplasia: RhoA-ROCK-β-catenin signaling axis and static & dynamic dual roles

BACKGROUND

The pathogenesis of benign prostatic hyperplasia (BPH) has not been fully elucidated. Ras homology family member A (RhoA) plays an important role in regulating cell cytoskeleton, growth and fibrosis. The role of RhoA in BPH remains unclear.

METHODS

This study aimed to clarify the expression, functional activity and mechanism of RhoA in BPH. Human prostate tissues, human prostate cell lines, BPH rat model were used. Cell models of RhoA knockdown and overexpression were generated. Immunofluorescence staining, quantitative real time PCR (qRT-PCR), Western blotting, cell counting kit-8 (CCK-8), flow cytometry, phalloidine staining, organ bath study, gel contraction assay, protein stability analysis, isolation and extraction of nuclear protein and cytoplasmic protein were performed.

RESULTS

In this study we found that RhoA was localized in prostate stroma and epithelial compartments and was up-regulated in both BPH patients and BPH rats. Functionally, RhoA knockdown induced cell apoptosis and inhibited cell proliferation, fibrosis, epithelial-mesenchymal transformation (EMT) and contraction. Consistently, overexpression of RhoA reversed all aforementioned processes. More importantly, we found that β-catenin and the downstream of Wnt/β-catenin signaling, including C-MYC, Survivin and Snail were up-regulated in BPH rats. Downregulation of RhoA significantly reduced the expression of these proteins. Rho kinase inhibitor Y-27632 also down-regulated β-catenin protein in a concentration-dependent manner. However, overexpression of β-catenin did not affect RhoA-ROCK levels, suggesting that β-catenin was the downstream of RhoA-ROCK regulation. Further data suggested that RhoA increased nuclear translocation of β-catenin and up-regulated β-catenin expression by inhibiting its proteasomal degradation, thereby activating Wnt/β-catenin signaling. Overexpression of β-catenin partially reversed the changes in cell growth, fibrosis and EMT except cell contraction caused by RhoA downregulation. Finally, Y-27632 partially reversed prostatic hyperplasia in vivo, further suggesting the potential of RhoA-ROCK signaling in BPH treatment.

CONCLUSION

Our novel data demonstrated that RhoA regulated both static and dynamic factors of BPH, RhoA-ROCK-β-catenin signaling axis played an important role in the development of BPH and might provide more possibilities for the formulation of subsequent clinical treatment strategies.

Targeting BRD4 attenuates the stemness and aggressiveness of ameloblastoma

BACKGROUND

BRD4, belonging to the bromodomain extra-terminal (BET) protein family, plays a unique role in tumor progression. However, the potential impact of BRD4 in ameloblastoma (AM) remains largely unknown. Herein, we aimed to assess the expression and functional role of BRD4 in AM.

METHODS

The expression level of BRD4 was assessed by immunohistochemistry. The proliferation, migration, invasion, and tumorigenic abilities of AM cells were assessed by a series of assays. To explore the molecular expression profile of BRD4-depleted AM cells, RNA sequencing (RNA-seq) was performed. Bioinformatic analysis was performed on AM expression matrices obtained from the Gene Expression Omnibus (GEO). The therapeutic efficacy of BET-inhibitors (BETi) was assessed with AM patient-derived organoids.

RESULTS

Upregulation of BRD4 was observed in conventional AMs, recurrent AMs, and ameloblastic carcinomas. Depletion of BRD4 inhibited proliferation, invasion, migration, and tumorigenesis in AM. Administration of BETi attenuated the aggressiveness of AM and the growth of AM patient-derived organoids. Bioinformatic analysis indicated that BRD4 may promote AM progression by regulating the Wnt pathway and stemness-associated pathways.

CONCLUSION

BRD4 increases the aggressiveness and promotes the recurrence of ameloblastoma by regulating the Wnt pathway and stemness-associated pathways. These findings highlight BRD4 as a promising therapeutic target in AM management.

Prostate Cancer Stem Cells: Biology and Treatment Implications

Stem cells differentiate into mature organ/tissue-specific cells at a steady pace under normal conditions, but their growth can be accelerated during the process of tissue healing or in the context of certain diseases. It is postulated that the proliferation and growth of carcinomas are sustained by the presence of a vital cellular compartment resembling stem cells residing in normal tissues: 'stem-like cancer cells' or cancer stem cells (CSCs). Mutations in prostate stem cells can lead to the formation of prostate cancer. Prostate CSCs (PCSCs) have been identified and partially characterized. These express surface markers include CD44, CD133, integrin α2β1, and pluripotency factors like OCT4, NANOG, and SOX2. Several signaling pathways are also over-activated, including Notch, PTEN/Akt/PI3K, RAS-RAF-MEK-ERK and HH. Moreover, PCSCs appear to induce resistance to radiotherapy and chemotherapy, while their presence has been linked to aggressive cancer behavior and higher relapse rates. The development of treatment policies to target PCSCs in tumors is appealing as radiotherapy and chemotherapy, through cancer cell killing, trigger tumor repopulation via activated stem cells. Thus, blocking this reactive stem cell mobilization may facilitate a positive outcome through cytotoxic treatment.

Recent advances and future perspectives in the therapeutics of prostate cancer

Prostate cancer (PC) is one of the most common cancers in males and the fifth leading reason of death. Age, ethnicity, family history, and genetic defects are major factors that determine the aggressiveness and lethality of PC. The African population is at the highest risk of developing high-grade PC. It can be challenging to distinguish between low-risk and high-risk patients due to the slow progression of PC. Prostate-specific antigen (PSA) is a revolutionary discovery for the identification of PC. However, it has led to an increase in over diagnosis and over treatment of PC in the past few decades. Even if modifications are made to the standard PSA testing, the specificity has not been found to be significant. Our understanding of PC genetics and proteomics has improved due to advances in different fields. New serum, urine, and tissue biomarkers, such as PC antigen 3 (PCA3), have led to various new diagnostic tests, such as the prostate health index, 4K score, and PCA3. These tests significantly reduce the number of unnecessary and repeat biopsies performed. Chemotherapy, radiotherapy, and prostatectomy are standard treatment options. However, newer novel hormone therapy drugs with a better response have been identified. Androgen deprivation and hormonal therapy are evolving as new and better options for managing hormone-sensitive and castration-resistant PC. This review aimed to highlight and discuss epidemiology, various risk factors, and developments in PC diagnosis and treatment regimens.

ALDOC promotes non-small cell lung cancer through affecting MYC-mediated UBE2N transcription and regulating Wnt/β-catenin pathway

Despite advancements in therapeutic options, the overall prognosis for non-small cell lung cancer (NSCLC) remains poor. Therefore, it is crucial to further explore the etiology and targets for novel treatments to effectively manage NSCLC. In this study, immunohistochemistry was used to analyze the expression of aldolase, fructose-bisphosphate C (ALDOC) protein in tumor tissues and adjacent non-malignant tissues from 79 NSCLC patients. Our findings revealed that ALDOC was overexpressed in NSCLC tissues. ALDOC expression was associated with lymph node metastasis, lymphatic metastasis and pathological stage. In addition, Kaplan-Meier analysis showed that higher ALDOC levels were indicative of a poorer prognosis. Additionally, we observed elevated ALDOC mRNA levels in NSCLC cell lines relative to normal cells. To investigate the functional roles of ALDOC, we infected cells with small interfering RNA against ALDOC, which led to attenuated proliferation and migration, as well as ameliorated apoptosis. Furthermore, through our investigations, we discovered that ubiquitin-conjugating enzyme E2N (UBE2N) acts as a downstream factor of ALDOC. ALDOC promoted NSCLC through affecting MYC-mediated UBE2N transcription and regulating the Wnt pathway. More importantly, we found that downregulation of UBE2N or the use of Wnt pathway inhibitor could reverse the promoting effects of ALDOC elevation on NSCLC development in vitro and in vivo. Based on these findings, our study highlights the potential of ALDOC as a future therapeutic target for NSCLC.

The Apoptotic and Anti-Warburg Effects of Brassinin in PC-3 Cells via Reactive Oxygen Species Production and the Inhibition of the c-Myc, SIRT1, and β-Catenin Signaling Axis

Though Brassinin is known to have antiangiogenic, anti-inflammatory, and antitumor effects in colon, prostate, breast, lung, and liver cancers, the underlying antitumor mechanism of Brassinin is not fully understood so far. Hence, in the current study, the apoptotic mechanism of Brassinin was explored in prostate cancer. Herein, Brassinin significantly increased the cytotoxicity and reduced the expressions of pro-Poly ADP-ribose polymerase (PARP), pro-caspase 3, and B-cell lymphoma 2 (Bcl-2) in PC-3 cells compared to DU145 and LNCaP cells. Consistently, Brassinin reduced the number of colonies and increased the sub-G1 population and terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling (TUNEL)-positive cells in the PC-3 cells. Of note, Brassinin suppressed the expressions of pyruvate kinase-M2 (PKM2), glucose transporter 1 (GLUT1), hexokinase 2 (HK2), and lactate dehydrogenase (LDH) as glycolytic proteins in the PC-3 cells. Furthermore, Brassinin significantly reduced the expressions of SIRT1, c-Myc, and β-catenin in the PC-3 cells and also disrupted the binding of SIRT1 with β-catenin, along with a protein-protein interaction (PPI) score of 0.879 and spearman's correlation coefficient of 0.47 being observed between SIRT1 and β-catenin. Of note, Brassinin significantly increased the reactive oxygen species (ROS) generation in the PC-3 cells. Conversely, ROS scavenger NAC reversed the ability of Brassinin to attenuate pro-PARP, pro-Caspase3, SIRT1, and β-catenin in the PC-3 cells. Taken together, these findings support evidence that Brassinin induces apoptosis via the ROS-mediated inhibition of SIRT1, c-Myc, β-catenin, and glycolysis proteins as a potent anticancer candidate.

siRNA-based approaches for castration-resistant prostate cancer therapy targeting the androgen receptor signaling pathway

Androgen deprivation therapy is a common treatment method for metastatic prostate cancer through lowering androgen levels; however, this therapy frequently leads to the development of castration-resistant prostate cancer (CRPC). This is attributed to the activation of the androgen receptor (AR) signaling pathway. Current treatments targeting AR are often ineffective mostly due to AR gene overexpression and mutations, as well as the presence of splice variants that accelerate CRPC progression. Thus there is a critical need for more specific medication to treat CRPC. Small interfering RNAs have shown great potential as a targeted therapy. This review discusses prostate cancer progression and the role of AR signaling in CRPC, and proposes siRNA-based targeted therapy as a promising strategy for CRPC.

PRPF19 promotes the proliferation, migration, and inhibits autophagy in prostate cancer by suppressing SLC40A1

Prostate cancer (PCa) is a common cancer and the leading cause of cancer-related death in men. To investigate the role of pre-mRNA processing factor 19 (PRPF19) in proliferation, migration of PCa, and evaluate the potential ability of PRPF19 as a therapeutic target. PRPF19 expression was analyzed from The Cancer Genome Atlas and GEPIA databank. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to evaluate the transcription of PRPF9 and solute carrier family 40 member 1 (SLC40A1). Immunohistochemistry (IHC) was used to test PRPF9 expression in PCa tissues. The cell viability and 5-ethynyl-2'-deoxyuridine incorporation analysis were performed to assess cell proliferation. Transwell assay was performed to investigate the migration and invasion of cancer cells. Western blot was used to measure the expression level of PRPF9, E-cadherin, Vimentin and α-smooth muscle actin (α-SMA), SLC40A1, LC3, Beclin-1 and ATG7. Immunofluorescence assay was performed to measure LC3 expression in PCa cells. The bioinformatic analysis revealed PRPF19 was highly expressed in PCa which was certified by qRT-PCR, western blot and IHC detection in PCa tissues. The proliferation of PCa cells could be promoted by PRPF19 overexpression and suppressed by PRPF19 knockdown. Moreover, the migration and invasion of PCa cells could be positively regulated by PRPF19 which promoted the expression of E-cadherin, Vimentin, and α-SMA. Furthermore, the expression of LC3, Beclin-1, and ATG7 was negatively regulated by PRPF19, indicating that PRPF19 inhibited autophagy in PCa cells. In the double knockdown of PRPF19 and SLC40A1, PRPF19 repressed the mRNA and reduced protein level of SLC40A1, and SLC40A1 antagonized effects of PRPF19 on proliferation, migration and autophagy of PCa cells. PRPF19 promoted proliferation and migration, and inhibited autophagy in PCa by attenuating SLC40A1 expression, indicating PRPF19 was a potential therapeutic target for PCa treatment.

Malignant function of nuclear factor-kappaB axis in prostate cancer: Molecular interactions and regulation by non-coding RNAs

Prostate carcinoma is a malignant situation that arises from genomic alterations in the prostate, leading to changes in tumorigenesis. The NF-κB pathway modulates various biological mechanisms, including inflammation and immune responses. Dysregulation of NF-κB promotes carcinogenesis, including increased proliferation, invasion, and therapy resistance. As an incurable disease globally, prostate cancer is a significant health concern, and research into genetic mutations and NF-κB function has the efficacy to facilitate the introduction of novel therapies. NF-κB upregulation is observed during prostate cancer progression, resulting in increased cell cycle progression and proliferation rates. Additionally, NF-κB endorses resistance to cell death and enhances the capacity for metastasis, particularly bone metastasis. Overexpression of NF-κB triggers chemoresistance and radio-resistance, and inhibition of NF-κB by anti-tumor compounds can reduce cancer progression. Interestingly, non-coding RNA transcripts can regulate NF-κB level and its nuclear transfer, offering a potential avenue for modulating prostate cancer progression.

ESS2 controls prostate cancer progression through recruitment of chromodomain helicase DNA binding protein 1

Molecular targeted therapy using poly (ADP-ribose) polymerase inhibitors has improved survival in patients with castration-resistant prostate cancer (CRPC). However, this approach is only effective in patients with specific genetic mutations, and additional drug discovery targeting epigenetic modulators is required. Here, we evaluated the involvement of the transcriptional coregulator ESS2 in prostate cancer. ESS2-knockdown PC3 cells dramatically inhibited proliferation in tumor xenografts in nude mice. Microarray analysis revealed that ESS2 regulated mRNA levels of chromodomain helicase DNA binding protein 1 (CHD1)-related genes and other cancer-related genes, such as PPAR-γ, WNT5A, and TGF-β, in prostate cancer. ESS2 knockdown reduced nuclear factor (NF)-κB/CHD1 recruitment and histone H3K36me3 levels on the promoters of target genes (TNF and CCL2). In addition, we found that the transcriptional activities of NF-κB, NFAT and SMAD2/3 were enhanced by ESS2. Tamoxifen-inducible Ess2-knockout mice showed delayed prostate development with hypoplasia and disruption of luminal cells in the ventral prostate. Overall, these findings identified ESS2 acts as a transcriptional coregulator in prostate cancer and ESS2 can be novel epigenetic therapeutic target for CRPC.

WDR3 promotes stem cell-like properties in prostate cancer by inhibiting USF2-mediated transcription of RASSF1A

BACKGROUND

WD repeat domain 3 (WDR3) is involved in tumor growth and proliferation, but its role in the pathological mechanism of prostate cancer (PCa) is still unclear.

METHODS

WDR3 gene expression levels were obtained by analyzing databases and our clinical specimens. The expression levels of genes and proteins were determined by a real-time polymerase chain reaction, western blotting and immunohistochemistry, respectively. Cell-counting kit-8 assays were used to measure the proliferation of PCa cells. Cell transfection was used to investigate the role of WDR3 and USF2 in PCa. Fluorescence reporter and chromatin immunoprecipitation assays were used to detect USF2 binding to the promoter region of RASSF1A. Mouse experiments were used to confirm the mechanism in vivo.

RESULTS

By analyzing the database and our clinical specimens, we found that WDR3 expression was significantly increased in PCa tissues. Overexpression of WDR3 enhanced PCa cell proliferation, decreased cell apoptosis rate, increased spherical cell number and increased indicators of stem cell-like properties. However, these effects were reversed by WDR3 knockdown. WDR3 was negatively correlated with USF2, which was degraded by promoting ubiquitination of USF2, and USF2 interacted with promoter region-binding elements of RASSF1A to depress PCa stemness and growth. In vivo studies showed that WDR3 knockdown reduced tumor size and weight, reduced cell proliferation and enhanced cell apoptosis.

CONCLUSIONS

WDR3 ubiquitinated USF2 and inhibited its stability, whereas USF2 interacted with promoter region-binding elements of RASSF1A. USF2 transcriptionally activated RASSF1A, which inhibited the carcinogenic effect of WDR3 overexpression.

Novel signatures of prostate cancer progression and therapeutic resistance

INTRODUCTION

The extensive heterogeneity of prostate cancer (PCa) and multilayered complexity of progression to castration-resistant prostate cancer (CRPC) have contributed to the challenges of accurately monitoring advanced disease. Profiling of the tumor microenvironment with large-scale transcriptomic studies have identified gene signatures that predict biochemical recurrence, lymph node invasion, metastases, and development of therapeutic resistance through critical determinants driving CRPC.

AREAS COVERED

This review encompasses understanding of the role of different molecular determinants of PCa progression to lethal disease including the phenotypic dynamic of cell plasticity, EMT-MET interconversion, and signaling-pathways driving PCa cells to advance and metastasize. The value of liquid biopsies encompassing circulating tumor cells and extracellular vesicles to detect disease progression and emergence of therapeutic resistance in patients progressing to lethal disease is discussed. Relevant literature was added from PubMed portal.

EXPERT OPINION

Despite progress in the tumor-targeted therapeutics and biomarker discovery, distant metastasis and therapeutic resistance remain the major cause of mortality in patients with advanced CRPC. No single signature can encompass the tremendous phenotypic and genomic heterogeneity of PCa, but rather multi-threaded omics-derived and phenotypic markers tailored and validated into a multimodal signature.

Characterization of olfactomedin 4+ cells in prostate and urethral-tube epithelium during murine postnatal development and in adult mice

Olfactomedin4 (Olfm4) is expressed in normal mouse prostate. However, Olfm4+ cells in the murine prostate have not been well characterized. In this study, we generated an Olfm4^eGFP reporter mouse line with C57BL/6 mice and investigated the distribution of Olfm4/eGFP-expressing cells during postnatal development from P1, P7, P14, P20, P42, P56 to adult male mouse prostate and urethral tube. We observed Olfm4/eGFP expression in urogenital and prostatic epithelial cells during early postnatal development, which persisted into adulthood in urethral-tube and anterior-prostate (AP) epithelium. We found Olfm4+ cells are E-cadherin+/CD44+/Foxa1+ and some of subpopulation are Ck8+/Ck5+/Sca-1-/Ck4-/Syn- in the adult mouse AP epithelium. Functional studies of single-cell preparations of Olfm4/eGFP-expressing cells isolated from adult Olfm4^eGFP mouse prostate demonstrated that Olfm4+ cells can grow and form colonies, spheres, or organoids in culture. Bioinformatic analysis of Olfm4+ cells using single-cell RNA sequencing meta data in adult mouse urethra (GSE145865) identified upregulation of genes related to cell and tissue migration and development, as well as upregulation of xenobiotic metabolism signaling pathways. In conclusion, Olfm4^eGFP mouse is a novel model to further study Olfm4's biological functions and Olfm4+ cells may contribute importantly to cellular processes supporting development and homeostasis of the epithelium in murine prostate and urethral tube.

Hyperphosphorylated PTEN exerts oncogenic properties

PTEN is a multifaceted tumor suppressor that is highly sensitive to alterations in expression or function. The PTEN C-tail domain, which is rich in phosphorylation sites, has been implicated in PTEN stability, localization, catalytic activity, and protein interactions, but its role in tumorigenesis remains unclear. To address this, we utilized several mouse strains with nonlethal C-tail mutations. Mice homozygous for a deletion that includes S370, S380, T382 and T383 contain low PTEN levels and hyperactive AKT but are not tumor prone. Analysis of mice containing nonphosphorylatable or phosphomimetic versions of S380, a residue hyperphosphorylated in human gastric cancers, reveal that PTEN stability and ability to inhibit PI3K-AKT depends on dynamic phosphorylation-dephosphorylation of this residue. While phosphomimetic S380 drives neoplastic growth in prostate by promoting nuclear accumulation of β-catenin, nonphosphorylatable S380 is not tumorigenic. These data suggest that C-tail hyperphosphorylation creates oncogenic PTEN and is a potential target for anti-cancer therapy.

Eprinomectin: a derivative of ivermectin suppresses growth and metastatic phenotypes of prostate cancer cells by targeting the β-catenin signaling pathway

PURPOSE

Prostate cancer (PCa) is the second leading cause of cancer death among men in the USA. The emergence of resistance to androgen deprivation therapy gives rise to metastatic castration-resistant prostate cancer. Eprinomectin (EP) is a member of a family of drugs called avermectins with parasiticide and anticancer properties. The pupose of this study was to evaluate the anticancer effects of EP against metastatic PCa using cellular models.  METHODS: In this study, we have investigated the effect of EP's anticancer properties and delineated the underlying mechanisms in the DU145 cellular model using several assays such as cell viability assay, colony formation assay, wound-healing assay, immunofluorescence, apoptosis assay, cell cycle analysis, and immunoblotting.

RESULTS

Our results indicate that EP significantly inhibits the cell viability, colony formation, and migration capacities of DU145 cells. EP induces cell cycle arrest at the G0/G1 phase, apoptosis via the activation of different caspases, and autophagy through the increase in the generation of reactive oxygen species and endoplasmic reticulum stress. In addition, EP downregulates the expression of cancer stem cell markers and mediates the translocation of β-catenin from the nucleus to the cytoplasm, indicating its role in inhibiting downstream target genes such as c-Myc and cyclin D1.

CONCLUSION

Our study shows that EP has tremendous potential to target metastatic PCa cells and provides new avenues for therapeutic approaches for advanced PCa.

HIRA-mediated loading of histone variant H3.3 controls androgen-induced transcription by regulation of AR/BRD4 complex assembly at enhancers

Incorporation of histone variant H3.3 comprises active territories of chromatin. Exploring the function of H3.3 in prostate cancer (PC), we found that knockout (KO) of H3.3 chaperone HIRA suppresses PC growth in vitro and in xenograft settings, deregulates androgen-induced gene expression and alters androgen receptor (AR) binding within enhancers of target genes. H3.3 affects transcription in multiple ways, including activation of p300 by phosphorylated H3.3 at Ser-31 (H3.3S31Ph), which results in H3K27 acetylation (H3K27Ac) at enhancers. In turn, H3K27Ac recruits bromodomain protein BRD4 for enhancer-promoter interaction and transcription activation. We observed that HIRA KO reduces H3.3 incorporation, diminishes H3.3S31Ph and H3K27Ac, modifies recruitment of BRD4. These results suggest that H3.3-enriched enhancer chromatin serves as a platform for H3K27Ac-mediated BRD4 recruitment, which interacts with and retains AR at enhancers, resulting in transcription reprogramming. AR KO reduced levels of H3.3 at enhancers, indicating feedback mechanism. In addition, HIRA KO deregulates glucocorticoid-driven transcription, suggesting a common H3.3/HIRA-dependent mechanism of nuclear receptors function. Expression of HIRA complex proteins is increased in PC compared with normal prostate tissue, especially in high-risk PC groups, and is associated with a negative prognosis. Collectively, our results demonstrate function of HIRA-dependent H3.3 pathway in regulation of nuclear receptors activity.

Key points

*H3.3 at enhancers promotes acetylation of H3K27Ac and retention of AR/BRD4 complex for transcription regulation*Knockout of H3.3 chaperone HIRA suppresses PC cells growth and deregulates androgen-induced transcription*H3.3/HIRA pathway regulates both AR and GR, suggesting a common HIRA/H3.3 mechanism of nuclear receptors function.

Instrumental and transcriptome analysis reveals the chemotherapeutic effects of doxorubicin-loaded black phosphate nanosheets on abiraterone-resistant prostate cancer

Prostate cancer is the second most common cause of cancer-related deaths in men and is common in most developed countries. Androgen deprivation therapy (ADT) that uses abiraterone acetate (AA) is an effective second-line treatment for prostate cancer. However, approximately 20-40% of patients develop primary resistance to abiraterone post-treatment. In this study, we aimed to understand the molecular mechanisms underlying the development of abiraterone resistance in prostate cancer cells and the potential use of black phosphorus nanosheets (BPNS) for treating abiraterone-resistant prostate cancer. We first established abiraterone-resistant prostate cancer PC-3 cells and found that these cells have higher migration ability than normal prostate cancer cells. Using comparative transcriptomic and bioinformatics analyses between abiraterone-sensitive PC-3 and abiraterone-resistant PC-3 cells, we highlighted the differentially expressed genes (DEGs) involved in the biological processes related to prostate gland morphogenesis, drug response, immune response, angiogenesis. We further studied the therapeutic effects of BPNS. Our results show that BPNS reduced the proliferation and migration of abiraterone-resistant PC-3 cells. Bioinformatics analysis, including gene ontology, Kyoto encyclopedia of genes and genomes enrichment analysis, and ingenuity pathway analysis (IPA) of the DEGs, suggested that BPNS treatment controlled cancer cell proliferation, metastasis, and oncogenic signaling pathways. Furthermore, the IPA gene network highlighted the involvement of the MMP family, ATF, and notch families in the anti-prostate cancer function of BPNS. Our findings suggest that BPNS may have a chemotherapeutic function in treating abiraterone-resistant prostate cancer.

Scope of Wnt signaling in the precise diagnosis and treatment of breast cancer

Malignant breast cancers are responsible for a growing number of deaths among women globally. The latest research has demonstrated that Wnt signaling is pivotal in this disease, regulating a safe microenvironment for the growth and proliferation of cancer cells {AuQ: Edit OK?}, sustained stemness, resistance to therapy, and aggregate formation. The three highly conserved {AuQ: Edit OK?} Wnt signaling pathways, Wnt-planar cell polarity (PCP), Wnt/β-catenin signaling and Wnt-Ca²⁺ signaling, assume various roles in the maintenance and amelioration of breast cancer. In this review, we examine ongoing studies on the Wnt signaling pathways and discuss how dysregulation of these pathways promotes breast cancers. We also look at how Wnt dysregulation could be exploited to foster new treatments for malignant breast cancers.