Modulation of androgen receptor by FOXA1 and FOXO1 factors in prostate cancer

The clock gene BHLHE40 and atypical CCNG2 control androgen-induced cellular senescence as a novel tumor suppressive pathway in prostate cancer

BACKGROUND

The androgen receptor (AR) is a drug target used to inhibit AR and prostate cancer (PCa) growth. Surprisingly, treatment with supraphysiological androgen level (SAL), used in bipolar androgen therapy, inhibits growth of PCa suggesting a tumor-suppressive activity by SAL. SAL was shown to induce cellular senescence in PCa.

METHODS

RNA-seq and transcriptome analysis, ChIP-seq, human 3D PCa spheroids, mouse xenografted castration-resistant PCa, knockdown and overexpression, Co-immunoprecipitation (Co-IP), translocation analysis, immune detection, qRT-PCR, protein-protein interaction modelling.

RESULTS

Here, mice xenografts with castration-resistant PCa tumors show that SAL inhibits cancer growth in vivo suggesting that SAL activates a tumor-suppressive mechanism. RNA-seq and ChIP-seq revealed the clock gene BHLHE40 is a novel direct AR target. Compared to adjacent human prostate tissues, the expression of BHLHE40 is reduced in PCa tumors and associated with reduced survival. Knockdown suggests that BHLHE40 mediates SAL-induced cellular senescence including tumor spheroids. Interestingly, a large overlap of differentially expressed gene sets was identified between BHLHE40 and SAL leading to the identification of four classes of SAL-BHLHE40 transcriptome landscapes. Co-IP and modelling suggest binding of BHLHE40 to AR and their co-translocation into nucleus by SAL treatment. Further, RNA-seq and ChIP-seq analysis indicate that the atypical tumor suppressive cyclin G2 emerged as a novel downstream target of BHLHE40 and a mediator of SAL-induced cellular senescence.

CONCLUSIONS

The data provide evidence of the tumor suppressive activity of SAL and a novel signaling by the AR-BHLHE40-CCNG2 axis for androgen-induced cellular senescence, linking circadian rhythm factor to androgen signaling as a novel tumor suppressive pathway.

CAPN2 promotes apalutamide resistance in metastatic hormone-sensitive prostate cancer by activating protective autophagy

Apalutamide, a novel endocrine therapy agent, has been shown to significantly improve the prognosis of patients with metastatic hormone-sensitive prostate cancer (mHSPC). However, resistance to apalutamide has also been reported, and the underlying mechanism for this response has yet to be clearly elucidated. First, this study established apalutamide-resistant prostate cancer (PCa) cells, and confirmed that apalutamide activated the release of calcium ions (Ca2+) and endoplasmic reticulum stress (ERS) to enhance autophagy. Second, RNA sequencing, western blotting, and immunohistochemistry revealed significantly decreased Calpain 2 (CAPN2) expression in the apalutamide-resistant PCa cells and tissues. Furthermore, immunofluorescence and transmission electron microscopy (TEM) showed that CAPN2 promoted apalutamide resistance by activating protective autophagy. CAPN2 promoted autophagy by reducing Forkhead Box O1 (FOXO1) degradation while increasing nuclear translocation via nucleoplasmic protein isolation and immunofluorescence. In addition, FOXO1 promoted protective autophagy through the transcriptional regulation of autophagy-related gene 5 (ATG5). Furthermore, a dual-fluorescence assay confirmed that transcription factor 3 (ATF3) stimulation promoted CAPN2-mediated autophagy activation via transcriptional regulation. In summary, CAPN2 activated protective autophagy by inhibiting FOXO1 degradation and promoting its nuclear translocation via transcriptional ATG5 regulation. ATF3 activation and transcriptional CAPN2 regulation jointly promoted this bioeffect. Thus, our findings have not only revealed the mechanism underlying apalutamide resistance, but also provided a promising new target for the treatment of metastatic PCa.

Emerging proteins involved in castration‑resistant prostate cancer via the AR‑dependent and AR‑independent pathways (Review)

Despite achieving optimal initial responses to androgen deprivation therapy, most patients with prostate cancer eventually progress to a poor prognosis state known as castration‑resistant prostate cancer (CRPC). Currently, there is a notable absence of reliable early warning biomarkers and effective treatment strategies for these patients. Although androgen receptor (AR)‑independent pathways have been discovered and acknowledged in recent years, the AR signaling pathway continues to play a pivotal role in the progression of CRPC. The present review focuses on newly identified proteins within human CRPC tissues. These proteins encompass both those involved in AR‑dependent and AR‑independent pathways. Specifically, the present review provides an in‑depth summary and analysis of the emerging proteins within AR bypass pathways. Furthermore, the significance of these proteins as potential biomarkers and therapeutic targets for treating CRPC is discussed. Therefore, the present review offers valuable theoretical insights and clinical perspectives to comprehensively enhance the understanding of CRPC.

Enzalutamide-induced signatures revealed by epigenetic plasticity using single-cell multi-omics sequencing in prostate cancer

Prostate cancer is morphologically and molecularly heterogeneous, which poses obstacles for early diagnosis and treatment. Advancements in understanding the heterogeneity of prostate cancer will help navigate through these challenges and ultimately benefit patients. In this study, we integrated single-cell sequencing for transposase-accessible chromatin and whole transcriptome in prostate cancer cell lines, aiming to decode the epigenetic plasticity upon enzalutamide (ENZ) treatment. By comparing the cell populations representing early-treatment response or resistance to the initial tumor cells, we identified seven signature gene sets; they present consistent trends of chromatin closing co-occurred with down-regulated genes during early response and chromatin opening with up-regulated genes upon maintaining drug resistance. In the molecular signatures, we found genes ZNF337, MAPK15, and ESRRG are favorable in progression-free prognosis during early response, while genes CCDC150, CCDC18, and POC1A marked poor prognosis underpinning the pre-existing drug resistance in The Cancer Genome Atlas prostate adenocarcinoma cohort. Ultimately, drug-target analyses nominated combinatory drug candidates to either enhance early-treatment response or potentially overcome ENZ resistance. Together, our integrative, single-cell multi-omics approach in pre-clinical models is effective in identifying informative signatures from complex molecular events, illustrating diverse drug responses in prostate cancer, and invoking novel combinatory drug strategies to inform clinical decision making.

The molecular consequences of androgen activity in the human breast

Estrogen and progesterone have been extensively studied in the mammary gland, but the molecular effects of androgen remain largely unexplored. Transgender men are recorded as female at birth but identify as male and may undergo gender-affirming androgen therapy to align their physical characteristics and gender identity. Here we perform single-cell-resolution transcriptome, chromatin, and spatial profiling of breast tissues from transgender men following androgen therapy. We find canonical androgen receptor gene targets are upregulated in cells expressing the androgen receptor and that paracrine signaling likely drives sex-relevant androgenic effects in other cell types. We also observe involution of the epithelium and a spatial reconfiguration of immune, fibroblast, and vascular cells, and identify a gene regulatory network associated with androgen-induced fat loss. This work elucidates the molecular consequences of androgen activity in the human breast at single-cell resolution.

DETECTION OF DISEASE‐CAUSING MUTATIONS IN PROSTATE CANCER BY NGS SEQUENCING

Gene mutations may affect the fate of many tumors including prostate cancer (PCa); therefore, the research of specific mutations associated with tumor outcomes might help the urologist to identify the best therapy for PCa patients such as surgical resection, adjuvant therapy or active surveillance. Genomic DNA (gDNA) was extracted from 48 paraffin‐embedded PCa samples and normal paired tissues. Next, gDNA was amplified and analyzed by next‐generation sequencing (NGS) using a specific gene panel for PCa. Raw data were refined to exclude false‐positive mutations; thus, variants with coverage and frequency lower than 100× and 5%, respectively were removed. Mutation significance was processed by Genomic Evolutionary Rate Profiling, ClinVar, and Varsome tools. Most of 3000 mutations (80%) were single nucleotide variants and the remaining 20% indels. After raw data elaboration, 312 variants were selected. Most mutated genes were KMT2D (26.45%), FOXA1 (16.13%), ATM (15.81%), ZFHX3 (9.35%), TP53 (8.06%), and APC (5.48%). Hot spot mutations in FOXA1, ATM, ZFHX3, SPOP, and MED12 were also found. Truncating mutations of ATM, lesions lying in hot spot regions of SPOP and FOXA1 as well as mutations of TP53 correlated with poor prognosis. Importantly, we have also found some germline mutations associated with hereditary cancer‐predisposing syndrome. gDNA sequencing of 48 cancer tissues by NGS allowed to detect new tumor variants as well as confirmed lesions in genes linked to prostate cancer. Overall, somatic and germline mutations linked to good/poor prognosis could represent new prognostic tools to improve the management of PCa patients.

Regulatory mechanism of androgen receptor on NCAPD3 gene expression in prostate cancer

BACKGROUND

Androgen receptor (AR) is an essential transcriptional factor that contributes to the development and progression of prostate cancer (PCa). NCAPD3 is a component of the condensin II complex and plays a critical role in cell mitosis by regulating chromosome condensation; however, the relationship between NCAPD3 and AR remains unknown.

METHODS

Transcriptome sequencing assay is carried out to analyze the expression of the NCAP family in clinic samples. Chromatin immunoprecipitation (ChIP) sequencing, ChIP assay, and dual-luciferase assay are used to identify the androgen-responsive element in NCAPD3 enhancer. Immunohistochemistry, quantitative reverse transcription-polymerase chain reaction, and western-blot assay are employed to check the expression of genes in PCa tissues and in PCa cells. Confocal immunofluorescence microscopy analysis is used for identifying the regulation of AR on NCAPD3-mediated chromosome condensation. Colony formation, cell cycle assay, wound healing assay, and transwell experiments are used to explore the regulation of AR on the functions of NCAPD3. In vivo experiment is employed to identify in vitro experimental results.

RESULTS

NCAPD3 is an androgen/AR axis-targeted gene and is involved in AR-induced PCa cell proliferation, migration, and invasion in vitro and in vivo. Androgen treatment and AR overexpression increase the expression of NCAPD3 in PCa cell lines. The canonical exist in the enhancer region of NCAPD3. Androgen/AR axis regulates NCAPD3-invovled chromosome condensation during cell mitosis.

CONCLUSIONS

Our report demonstrated that NCAPD3 is an androgen-responsive gene and upregulated by androgen/AR axis and involved in AR-promoted progression of PCa, suggesting a potential role of NCAPD3 in the PCa development.

MicroRNA-629 promotes the tumorigenesis of non-small-cell lung cancer by targeting FOXO1 and activating PI3K/AKT pathway

OBJECTIVE

MicroRNA-629 (miR-629) has been found to play an important role in the pathogenesis of human cancers. However, the function of miR-629 is still unknown in non-small-cell lung cancer (NSCLC). The purpose of this study is to preliminarily elucidate the regulatory mechanism of miR-629 in NSCLC.

MATERIALS AND METHODS

The mRNA and protein expression was measured by real-time quantitative polymerase chain reaction (RT-qPCR) and western blot analysis. The function of miR-629 was investigated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) and Transwell assays. The relationship between miR-629 and FOXO1 was confirmed by dual luciferase assay.

RESULTS

MiR-629 was upregulated in NSCLC tissues and cells. High expression of miR-629 predicted poor prognosis in patients with NSCLC. Moreover, miR-629 promoted cell proliferation, migration and invasion in NSCLC cells. In addition, FOXO1 was confirmed as a direct target of miR-629 in NSCLC. Furthermore, knockdown of FOXO1 also promoted proliferation, migration and invasion of NSCLC cells. More importantly, overexpression of FOXO1 weakened the carcinogenesis of miR-629 in NSCLC. Besides that, miR-629 promoted EMT and activated the PI3K/AKT pathway in NSCLC.

CONCLUSIONS

MiR-629 promotes the progression of NSCLC by targeting FOXO1 and regulating EMT/PI3K/AKT pathway.

Characterization of Novel Progression Factors in Castration-Resistant Prostate Cancer Based on Global Comparative Proteome Analysis

Simple Summary

Here, we investigated prostate cancer (PCa) tissues at each stage of progression, from benign prostatic hyperplasia to castration-resistant prostate cancer (CRPC), based on quantitative proteomic technology, including tissues after androgen deprivation therapy (ADT). In total, we identified 4768 proteins, and 4069 of them were quantified. We performed a systematic bioinformatics analysis of 865 differentially expressed proteins (DEPs) in the combined PCa tissues. We found 15 DEPs, including FOXA1 and HMGN1–3, as novel factors were significantly involved in the progression to CRPC after ADT in T3G3. All targets were verified to have increased levels of FOXA1 and HMGN1–3 in CRPC by immunoblotting and indirect enzyme-linked immunosorbent assay. The FOXA1 and HMGN1–3 proteins could be used as CRPC-related factors in clinical therapeutic agents.

Abstract

Identifying the biological change from hormone-naïve prostate cancer to castration-resistant prostate cancer (CRPC) is a major clinical challenge for developing therapeutic agents. Although the pathways that lead to CRPC are not fully completely understood, recent evidence demonstrates that androgen signaling is often maintained through varied mechanisms. Androgen deprivation therapy (ADT) is used as a primary treatment for preventing the progression of prostate cancer (PCa). Here we investigated PCa tissues at each stage of progression, from benign prostatic hyperplasia (BPH) to CRPC, based on quantitative proteomic technology, including tissues after ADT. In total, 4768 proteins were identified in this study, of which 4069 were quantified in the combined PCa tissues. Among the quantified proteins, 865 were differentially expressed proteins (21.2%). Based on the quantitative protein results, we performed systematic bioinformatics analysis and found that the levels of 15 proteins, including FOXA1 and HMGN1–3, increased among T3G3, T3GX, and CRPC, despite the ADT. Among all targets, we verified the increased levels of FOXA1 and HMGN1–3 in CRPC by immunoblotting and indirect enzyme-linked immunosorbent assay. In summary, we discuss the changes in intracellular factors involved in the progression of CRPC PCa despite ADT. Moreover, we suggest that FOXA1 and HMGN1–3 proteins could be used as potential CRPC-related factors in clinical therapeutic agents.

A Machine Learning Approach to Differentiate Two Specific Breast Cancer Subtypes Using Androgen Receptor Pathway Genes

Triple-negative breast cancer is a heterogeneous disease with different molecular and histological subtypes. The Androgen receptor is expressed in a portion of triple-negative breast cancer cases and the activation of the androgen receptor pathway is thought to be a molecular subtyping signature as well as a therapeutic target for triple-negative breast cancer. Thus, identification of the androgen receptor pathway status is important for both molecular characterization andclinical management. In this study, we investigate the expression of the androgen receptor pathway in metaplastic breast cancer and luminal androgen receptor subtypes of triple-negative breast cancer and found that the androgen receptor pathway was downregulated in metaplastic breast cancer compared to luminal androgen receptor subtype. Using random forest, we found that the two subtypes of breast cancer can be molecularly classified with the gene expression of the androgen receptor pathway.

The Influence of Anti-Diabetic Drugs on Prostate Cancer

The incidences of prostate cancer (PC) and diabetes are increasing, with a sustained trend. The occurrence of PC and type 2 diabetes mellitus (T2DM) is growing with aging. The correlation between PC occurrence and diabetes is noteworthy, as T2DM is correlated with a reduced risk of incidence of prostate cancer. Despite this reduction, diabetes mellitus increases the mortality in many cancer types, including prostate cancer. The treatment of T2DM is based on lifestyle changes and pharmacological management. Current available drugs, except insulin, are aimed at increasing insulin secretion (sulfonylureas, incretin drugs), improving insulin sensitivity (biguanides, thiazolidinediones), or increasing urinary glucose excretion (gliflozin). Comorbidities should be taken into consideration during the treatment of T2DM. This review describes currently known information about the mechanism and impact of commonly used antidiabetic drugs on the incidence and progression of PC. Outcomes of pre-clinical studies are briefly presented and their correlations with available clinical trials have also been observed. Available reports and meta-analyses demonstrate that most anti-diabetic drugs do not increase the risk during the treatment of patients with PC. However, some reports show a potential advantage of treatment of T2DM with specific drugs. Based on clinical reports, use of metformin should be considered as a therapeutic option. Moreover, anticancer properties of metformin were augmented while combined with GLP-1 analogs.

Long Non-Coding RNA Landscape in Prostate Cancer Molecular Subtypes: A Feature Selection Approach

Prostate cancer is one of the most common malignancies in men. It is characterized by a high molecular genomic heterogeneity and, thus, molecular subtypes, that, to date, have not been used in clinical practice. In the present paper, we aimed to better stratify prostate cancer patients through the selection of robust long non-coding RNAs. To fulfill the purpose of the study, a bioinformatic approach focused on feature selection applied to a TCGA dataset was used. In such a way, LINC00668 and long non-coding(lnc)-SAYSD1-1, able to discriminate ERG/not-ERG subtypes, were demonstrated to be positive prognostic biomarkers in ERG-positive patients. Furthermore, we performed a comparison between mutated prostate cancer, identified as "classified", and a group of patients with no peculiar genomic alteration, named "not-classified". Moreover, LINC00920 lncRNA overexpression has been linked to a better outcome of the hormone regimen. Through the feature selection approach, it was found that the overexpression of lnc-ZMAT3-3 is related to low-grade patients, and three lncRNAs: lnc-SNX10-87, lnc-AP1S2-2, and ADPGK-AS1 showed, through a co-expression analysis, significant correlation values with potentially druggable pathways. In conclusion, the data mining of publicly available data and robust bioinformatic analyses are able to explore the unknown biology of malignancies.

Fertility preservation in women with ovarian cancer: Finding new pathways: A case-control study

Background

Surgery and chemotherapy are the two most common treatments for cancers, including ovarian cancer. Although most ovarian cancers occur over the age of 45 yr, it may involve younger women and affect their reproductive ability.

Objective

To assess the expression of Leucine-rich repeat-containing G-protein coupled receptor 5 (LGR5), Forkhead Box O1 (FOXO1), and miR-340 genes in the ovarian cancer tissues as well as ovarian cancer cell lines.

Materials and Methods

In this case-control study, 30 ovarian cancer samples (with the average age of 37 ± 2.5 years) coupled with their non-tumor marginal tissue (as a control) were collected. Proliferated cell lines were treated with several concentrations of cisplatin, and the half maximal inhibitory concentration (IC50) of cisplatin was quantified by MTT-assay. After RNA extraction, cDNA synthesis and qRT-PCR were done. Finally, the results were analyzed.

Results

While the expression levels of miR-340 and FOXO1 genes in tumor samples displayed a significant reduction (p ≤ 0.001), the LGR5 gene presented a significant increase in expression (p ≤ 0.0001). However, conversely, the expression levels of miR-340 and FOXO1 genes in cisplatin-sensitive cell lines, after 24, 48, and 72 hr of cisplatin treatment, indicated a significant increase (p ≤ 0.001) while the expression of LGR5 gene showed a significant decrease in the cisplatin-sensitive cell line (p < 0.05).

Conclusion

The LGR5, FOXO1, and miR-340 genes can be targeted for early diagnosis and more accurate treatment of ovarian cancer and may prevent some of the ovarian cancer complications such as infertility.

Selective targeting of the androgen receptor-DNA binding domain by the novel antiandrogen SBF-1 and inhibition of the growth of prostate cancer cells

Prostate cancers are reliant on androgens for growth and survival. Clinicians and researchers are looking for potent treatments for the resistant forms of prostate cancer; however, a handful of small molecules used in the treatment of castration-resistant prostate cancer have not shown potent effects owing to the mutations in the AR (Androgen Receptor). We used SBF-1, a well-characterized antitumor agent with potent cytotoxic effects against different kinds of cancers and investigated its effect on human prostate cancer. SBF-1 substantially inhibited the proliferation, induced apoptosis, and caused cell cycle arrest in LNCaP and PC3/AR⁺ prostate cancer cell lines. SBF-1 inhibited the activation of the IGF-1-PNCA pathway, as demonstrated by decreased expression of IGF-1 (insulin-like growth factor 1), proliferating cell nuclear antigen (PCNA), and its downstream Bcl-2 protein. Using microscale thermophoresis (MST) and isothermal titration calorimetry (ITC) assays, we observed a direct binding of SBF-1 to the AR. SBF-1 binds to the AR-DBD (DNA-binding domain) and blocks the transcription of its target gene. SBF-1 demonstrated a potent antitumor effect in vivo; it inhibited AR signaling and suppressed tumor growth in animals. Our study suggests that SBF-1 is an inhibitor of the AR and might be used in the treatment of prostate cancer.

Small molecule JQ1 promotes prostate cancer invasion via BET-independent inactivation of FOXA1

Recent findings have shown that inhibitors targeting bromodomain and extraterminal domain (BET) proteins, such as the small molecule JQ1, are potent growth inhibitors of many cancers and hold promise for cancer therapy. However, some reports have also revealed that JQ1 can activate additional oncogenic pathways and may affect epithelial-to-mesenchymal transition (EMT). Therefore, it is important to address the potential unexpected effect of JQ1 treatment, such as cell invasion and metastasis. Here, we showed that in prostate cancer, JQ1 inhibited cancer cell growth but promoted invasion and metastasis in a BET protein-independent manner. Multiple invasion pathways including EMT, bone morphogenetic protein (BMP) signaling, chemokine signaling, and focal adhesion were activated by JQ1 to promote invasion. Notably, JQ1 induced upregulation of invasion genes through inhibition of Forkhead box protein A1 (FOXA1), an invasion suppressor in prostate cancer. JQ1 directly interacted with FOXA1 and inactivated FOXA1 binding to its interacting repressors TLE3, HDAC7, and NFIC, thereby blocking FOXA1-repressive function and activating the invasion genes. Our findings indicate that JQ1 has an unexpected effect of promoting invasion in prostate cancer. Thus, the ill effect of JQ1 or its derived therapeutic agents cannot be ignored during cancer treatment, especially in FOXA1-related cancers.

Protective Mechanism and Clinical Application of Hydrogen in Myocardial Ischemia-reperfusion Injury

Cardiovascular disease accounts for one-third of all deaths, with ischemic heart disease as the main cause of death. Under pathological conditions, ischemia-reperfusion injury (IRI) often occurs in tissues. Ischemic injury is mainly caused by anaerobic cell death and reperfusion which results in a wide range of inflammatory responses. These responses are able to increase tissue damage and even damage to the whole body. IRI can also aggravate the original cardiovascular disease during the treatment of cardiovascular disease. Therefore, it is particularly important to understand the mechanism of myocardial ischemia-reperfusion injury (MIRI) for clinical treatment and application. At the same time, it is necessary to find a safe, reliable and feasible method for treating MIRI to reduce the incidence of complications and mortality as well as improve the prognosis and quality of life of patients. As a selective antioxidant, hydrogen can neutralize excessive free radicals, has certain anti-apoptotic and anti-inflammatory effects and it has gradually become a focus and hotspot of preclinical and clinical research. Hydrogen has been shown to have a certain therapeutic effect on MIRI, which can provide a new therapeutic direction for the clinical treatment of myocardial ischemia-reperfusion injury. In this review, the protective mechanism and clinical application of hydrogen in myocardial ischemia-reperfusion injury is discussed.

Resistance to second generation antiandrogens in prostate cancer: pathways and mechanisms

Androgen deprivation therapy targeting the androgens/androgen receptor (AR) signaling continues to be the mainstay treatment of advanced-stage prostate cancer. The use of second-generation antiandrogens, such as abiraterone acetate and enzalutamide, has improved the survival of prostate cancer patients; however, a majority of these patients progress to castration-resistant prostate cancer (CRPC). The mechanisms of resistance to antiandrogen treatments are complex, including specific mutations, alternative splicing, and amplification of oncogenic proteins resulting in dysregulation of various signaling pathways. In this review, we focus on the major mechanisms of acquired resistance to second generation antiandrogens, including AR-dependent and AR-independent resistance mechanisms as well as other resistance mechanisms leading to CRPC emergence. Evolving knowledge of resistance mechanisms to AR targeted treatments will lead to additional research on designing more effective therapies for advanced-stage prostate cancer.

FOXO transcription factor family in cancer and metastasis

Forkhead box O (FOXO) transcription factors regulate diverse biological processes, affecting development, metabolism, stem cell maintenance and longevity. They have also been increasingly recognised as tumour suppressors through their ability to regulate genes essential for cell proliferation, cell death, senescence, angiogenesis, cell migration and metastasis. Mechanistically, FOXO proteins serve as key connection points to allow diverse proliferative, nutrient and stress signals to converge and integrate with distinct gene networks to control cell fate, metabolism and cancer development. In consequence, deregulation of FOXO expression and function can promote genetic disorders, metabolic diseases, deregulated ageing and cancer. Metastasis is the process by which cancer cells spread from the primary tumour often via the bloodstream or the lymphatic system and is the major cause of cancer death. The regulation and deregulation of FOXO transcription factors occur predominantly at the post-transcriptional and post-translational levels mediated by regulatory non-coding RNAs, their interactions with other protein partners and co-factors and a combination of post-translational modifications (PTMs), including phosphorylation, acetylation, methylation and ubiquitination. This review discusses the role and regulation of FOXO proteins in tumour initiation and progression, with a particular emphasis on cancer metastasis. An understanding of how signalling networks integrate with the FOXO transcription factors to modulate their developmental, metabolic and tumour-suppressive functions in normal tissues and in cancer will offer a new perspective on tumorigenesis and metastasis, and open up therapeutic opportunities for malignant diseases.

Darolutamide antagonizes androgen signaling by blocking enhancer and super-enhancer activation

Prostate cancer (PCa) is one of the most frequent tumor types in the male Western population. Early-stage PCa and late-stage PCa are dependent on androgen signaling, and inhibitors of the androgen receptor (AR) axis represent the standard therapy. Here, we studied in detail the global impact of darolutamide, a newly approved AR antagonist, on the transcriptome and AR-bound cistrome in two PCa cell models. Darolutamide strongly depleted the AR from gene regulatory regions and abolished AR-driven transcriptional signaling. Enhancer activation was blocked at the chromatin level as evaluated by H3K27 acetylation (H3K27ac), H3K4 monomethylation (H3K4me1), and FOXA1, MED1, and BRD4 binding. We identified genomic regions with high affinities for the AR in androgen-stimulated, but also in androgen-depleted conditions. A similar AR affinity pattern was observed in healthy and PCa tissue samples. High FOXA1, BRD4, H3K27ac, and H3K4me1 levels were found to mark regions showing AR binding in the hormone-depleted setting. Conversely, low FOXA1, BRD4, and H3K27ac levels were observed at regulatory sites that responded strongly to androgen stimulation, and AR interactions at these sites were blocked by darolutamide. Beside marked loss of AR occupancy, FOXA1 recruitment to chromatin was also clearly reduced after darolutamide treatment. We furthermore identified numerous androgen-regulated super-enhancers (SEs) that were associated with hallmark androgen and cell proliferation-associated gene sets. Importantly, these SEs are also active in PCa tissues and sensitive to darolutamide treatment in our models. Our findings demonstrate that darolutamide is a potent AR antagonist blocking genome-wide AR enhancer and SE activation, and downstream transcription. We also show the existence of a dynamic AR cistrome that depends on the androgen levels and on high AR affinity regions present in PCa cell lines and also in tissue samples.

The role of the androgen receptor in prostate development and benign prostatic hyperplasia: A review

Benign prostatic hyperplasia (BPH) is a benign enlargement of the prostate in which incidence increases linearly with age, beginning at about 50 years old. BPH is a significant source of morbidity in aging men by causing lower urinary tract symptoms and acute urinary retention. Unfortunately, the etiology of BPH incidence and progression is not clear. This review highlights the role of the androgen receptor (AR) in prostate development and the evidence for its involvement in BPH. The AR is essential for normal prostate development, and individuals with defective AR signaling, such as after castration, do not experience prostate enlargement with age. Furthermore, decreasing dihydrotestosterone availability through therapeutic targeting with 5α-reductase inhibitors diminishes AR activity and results in reduced prostate size and symptoms in some BPH patients. While there is some evidence that AR expression is elevated in certain cellular compartments, how exactly AR is involved in BPH progression has yet to be elucidated. It is possible that AR signaling within stromal cells alters intercellular signaling and a "reawakening" of the embryonic mesenchyme, loss of epithelial AR leads to changes in paracrine signaling interactions, and/or chronic inflammation aids in stromal or epithelial proliferation evident in BPH. Unfortunately, a subset of patients fails to respond to current medical approaches, forcing surgical treatment even though age or associated co-morbidities make surgery less attractive. Fundamentally, new therapeutic approaches to treat BPH are not currently forthcoming, so a more complete molecular understanding of BPH etiology is necessary to identify new treatment options.

TCF19 contributes to cell proliferation of non-small cell lung cancer by inhibiting FOXO1

Transcription factor 19 (TCF19) harbors a forkhead association (FHA) domain, a proline-rich region, a PHD or RING finger region, suggesting that TCF19 possesses a powerful function. However, its expression and function remains unknown in non-small-cell lung cancer (NSCLC). The function cluster analysis was carried out using Metascape website. 3-(4,5-Dimethyl-2-thiazolyl)2,5-diphenyl-2H-tetrazolium bromide (MTT), colony formation, and anchorage-independent growth ability assay were carried out to detect the effect of TCF19 on cell proliferation. Bromodeoxyuridine (Brdu) labeling and flow cytometry assay were used to evaluate the effect of TCF19 on cell-cycle progression. Quantitative polymerase chain reaction and chromatin immunoprecipitation assay were performed to investigate the mechanism by which TCF19 is involved in cell-cycle transition. By analyzing the publicly available dataset, The Cancer Genome Atlas (TCGA), we found that TCF19 is significantly increased in the lung adenocarcinoma (LAC) and squamous cell carcinoma (SCC), two primary histological subtype of NSCLC. Besides, further function cluster analysis exhibited that TCF19 may mainly participate in cell cycle. MTT, colony formation, and anchorage-independent growth ability assay confirmed that overexpression of TCF19 enhances the proliferation of both LAC and SCC cells. Besides, further experiments revealed that TCF19 contributes to cell cycle G1/S transition. Not only that, upregulation of TCF19 can inhibit the expression of p21, p27, and p57, while promote the expression of cyclin D1 by inhibiting FOXO1. Our research offers important evidence that TCF19 can promote cell-cycle progression of NSCLC cells, and TCF19 may served as novel therapeutic targets.

Identification of potential biomarkers and pivotal biological pathways for prostate cancer using bioinformatics analysis methods

Background

Prostate cancer (PCa) is a common urinary malignancy, whose molecular mechanism has not been fully elucidated. We aimed to screen for key genes and biological pathways related to PCa using bioinformatics method.

Methods

Differentially expressed genes (DEGs) were filtered out from the GSE103512 dataset and subjected to the gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. The protein–protein interactions (PPI) network was constructed, following by the identification of hub genes. The results of former studies were compared with ours. The relative expression levels of hub genes were examined in The Cancer Genome Atlas (TCGA) and Oncomine public databases. The University of California Santa Cruz Xena online tools were used to study whether the expression of hub genes was correlated with the survival of PCa patients from TCGA cohorts.

Results

Totally, 252 (186 upregulated and 66 downregulated) DEGs were identified. GO analysis enriched mainly in “oxidation-reduction process” and “positive regulation of transcription from RNA polymerase II promoter”; KEGG pathway analysis enriched mostly in “metabolic pathways” and “protein digestion and absorption.” Kallikrein-related peptidase 3, cadherin 1 (CDH1), Kallikrein-related peptidase 2 (KLK2), forkhead box A1 (FOXA1), and epithelial cell adhesion molecule (EPCAM) were identified as hub genes from the PPI network. CDH1, FOXA1, and EPCAM were validated by other relevant gene expression omnibus datasets. All hub genes were validated by both TCGA and Oncomine except KLK2. Two additional top DEGs (ABCC4 and SLPI) were found to be associated with the prognosis of PCa patients.

Conclusions

This study excavated the key genes and pathways in PCa, which might be biomarkers for diagnosis, prognosis, and potential therapeutic targets.

Systematically understanding the immunity leading to CRPC progression

Prostate cancer (PCa) is the most commonly diagnosed malignancy and the second leading cause of cancer-related death in American men. Androgen deprivation therapy (ADT) has become a standard treatment strategy for advanced PCa. Although a majority of patients initially respond to ADT well, most of them will eventually develop castration-resistant PCa (CRPC). Previous studies suggest that ADT-induced changes in the immune microenvironment (mE) in PCa might be responsible for the failures of various therapies. However, the role of the immune system in CRPC development remains unclear. To systematically understand the immunity leading to CRPC progression and predict the optimal treatment strategy in silico, we developed a 3D Hybrid Multi-scale Model (HMSM), consisting of an ODE system and an agent-based model (ABM), to manipulate the tumor growth in a defined immune system. Based on our analysis, we revealed that the key factors (e.g. WNT5A, TRAIL, CSF1, etc.) mediated the activation of PC-Treg and PC-TAM interaction pathways, which induced the immunosuppression during CRPC progression. Our HMSM model also provided an optimal therapeutic strategy for improving the outcomes of PCa treatment.

Osteoprotegerin promotes islet β cell proliferation in intrauterine growth retardation rats through the PI3K/AKT/FoxO1 pathway

Osteoprotegerin (OPG) is a critical factor involved in bone metabolism. The level of OPG is increased in the serum of diabetic patients; however, there is no consensus in prior studies on the role of OPG in regulating the function of islet β cells. A rat model of intrauterine growth retardation (IUGR) was established in the present study to investigate whether OPG could enhance the proliferation of β cells; and an in vitro culture model of rat islet β cell line INS-1 was used, to confirm the effect of OPG supplementation and reveal the possible mechanism. The results showed that endogenous OPG expression was reduced and normal proliferation of β cells was impaired in the IUGR islets. Exogenous supplement of OPG restored β cell proliferation to an extent in the IUGR rats, possibly associated with regulation of the PI3K/AKT/FoxO1 signalling, as evidenced by the changes of protein expression in the pathway. Furthermore, treating rat islet INS-1 cells with a PI3K inhibitor, LY294002, blunted the effects of OPG supplement in promoting cell cycle and suppressing cell apoptosis. Taken together, the present work demonstrated that OPG supplementation could improve the proliferation of islet β cells in IUGR, and the PI3K/AKT/FoxO1 pathway is involved in the underlying mechanism.

Lineage plasticity-mediated therapy resistance in prostate cancer

Therapy resistance is a significant challenge for prostate cancer treatment in clinic. Although targeted therapies such as androgen deprivation and androgen receptor (AR) inhibition are effective initially, tumor cells eventually evade these strategies through multiple mechanisms. Lineage reprogramming in response to hormone therapy represents a key mechanism that is increasingly observed. The studies in this area have revealed specific combinations of alterations present in adenocarcinomas that provide cells with the ability to transdifferentiate and perpetuate AR-independent tumor growth after androgen-based therapies. Interestingly, several master regulators have been identified that drive plasticity, some of which also play key roles during development and differentiation of the cell lineages in the normal prostate. Thus, further study of each AR-independent tumor type and understanding underlying mechanisms are warranted to develop combinational therapies that combat lineage plasticity in prostate cancer.

A review on the interactions between the tumor microenvironment and androgen receptor signaling in prostate cancer

Prostate cancer growth is controlled by androgen receptor signaling via both androgen-dependent and androgen-independent pathways. Furthermore, the prostate is an immune competent organ with inflammatory changes both within the systemic and local environment contributing to the reprogramming of the prostatic epithelium with consistently elevated lymphocyte infiltration and proinflammatory cytokines being found in prostate cancer. The crosstalk between the tumor microenvironment and androgen receptor signaling is complex with both protumorigenic and antitumorigenic roles observed. However, despite an increase in immune checkpoint inhibitors and inflammatory signaling blockades available for a range of cancer types, we are yet to see substantial progress in the treatment of prostate cancer. Therefore, this review aims to summarize the tumor microenvironment and its impact on androgen receptor signaling in prostate cancer.

Androgen receptor moonlighting in the prostate cancer microenvironment

Androgen receptor (AR) signaling is vital for the normal development of the prostate and is critically involved in prostate cancer (PCa). AR is not only found in epithelial prostate cells but is also expressed in various cells in the PCa-associated stroma, which constitute the tumor microenvironment (TME). In the TME, AR is expressed in fibroblasts, macrophages, lymphocytes and neutrophils. AR expression in the TME was shown to be decreased in higher-grade and metastatic PCa, suggesting that stromal AR plays a protective role against PCa progression. With that, the functionality of AR in stromal cells appears to deviate from the receptor's classical function as described in PCa cells. However, the biological action of AR in these cells and its effect on cancer progression remains to be fully understood. Here, we systematically review the pathological, genomic and biological literature on AR actions in various subsets of prostate stromal cells and aim to better understand the consequences of AR signaling in the TME in relation to PCa development and progression.

Effect of miR-182 on hepatic fibrosis induced by Schistosomiasis japonica by targeting FOXO1 through PI3K/AKT signaling pathway

The study aimed to investigate the impact of miR-182 and FOXO1 on S. japonica-induced hepatic fibrosis. Microarray analysis was performed to screen out differential expressed miRNAs and mRNAs. Rat hepatic fibrosis model and human hepatocellular cell line LX-2 were used to study the effect of miR-182 and FOXO1. qRT-PCR and Western blot were used to detect the expression of miR-182, FOXO1 or other fibrosis markers. The targeting relationship between FOXO1 and miR-182 was verified by luciferase reporter assay. Immunohistochemistry or immunofluorescence staining was conducted to detect FOXO1 or α-SMA in rat hepatic tissues. Cell viability and apoptosis were detected by MTT assay and flow cytometry. The expression of PI3K/AKT pathway-related proteins was detected by Western blot. miR-182 was highly expressed in liver fibrosis samples, and FOXO1 expression was negatively correlated with miR-182 expression. After transfection of miR-182, FOXO1 expression was down-regulated, with the results of LX-2 cells proliferation inhibition and apoptosis induction, as well as the aggravation of rat hepatic fibrosis. The expression of p-AKT/AKT and p-S6/S6 was increased, meaning that the PI3K/AKT signal pathway was activated. The results were reversed when treated with Wortmannin (PI3K inhibitor). After transfection of miR-182 inhibitor, FOXO1 expression was up-regulated, LX-2 cell proliferation was inhibited, and apoptosis rate was increased. High-expressed miR-182 and low-expressed FOXO1 promoted proliferation and inhibiting apoptosis on liver fibrosis cells, stimulating the development of S. japonica-induced hepatic fibrosis through feeding back to PI3K/AKT signaling pathway.

Genome-Wide Identification and Characterization of Fox Genes in the Honeybee, Apis cerana, and Comparative Analysis with Other Bee Fox Genes

The forkhead box (Fox) gene family, one of the most important families of transcription factors, participates in various biological processes. However, Fox genes in Hymenoptera are still poorly known. In this study, 14 Fox genes were identified in the genome of Apis cerana. In addition, 16 (Apis mellifera), 13 (Apis dorsata), 16 (Apis florea), 17 (Bombus terrestris), 16 (Bombus impatiens), and 18 (Megachile rotundata) Fox genes were identified in their genomes, respectively. Phylogenetic analyses suggest that FoxA is absent in the genome of A. dorsata genome. Similarly, FoxG is missing in the genomes A. cerana and A. dorsata. Temporal expression profiles obtained by quantitative real-time PCR revealed that Fox genes have distinct expression patterns in A. cerana, especially for three genes ACSNU03719T0 (AcFoxN4), ACSNU05765T0 (AcFoxB), and ACSNU07465T0 (AcFoxL2), which displayed high expression at the egg stage. Tissue expression patterns showed that FoxJ1 is significantly higher in the antennae of A. cerana and A. mellifera compared to other tissues. These results may facilitate a better understanding of the potential physiological functions of the Fox gene family in A. cerana and provide valuable information for a comprehensive functional analysis of the Fox gene family in Hymenopterans.

Combinatorial Effect of Abiraterone Acetate and NVP-BEZ235 on Prostate Tumor Progression in Rats

Use of drug combinations that target different pathways involved in the development and progression of prostate cancer (PCa) has emerged as an alternative to overcome the resistance caused by drug monotherapies. The antiandrogen abiraterone acetate and the PI3K/Akt inhibitor NVP-BEZ235 (BEZ235) may be suitable options for the prevention of drug resistance and the inhibition of PCa progression. The aim of the present study was to evaluate whether abiraterone acetate and BEZ235 achieve superior therapeutic effects to either drug administered as monotherapy, in the early stages of PCa in an androgen-dependent system. Our study showed that each drug might impair tumor growth by reducing proliferation and increasing cell death when administered as monotherapy. However, tumor growth continued to progress with each drug monotherapy and some important side effects were related to BEZ. Conversely, when used in combination, the drugs impaired the inflammatory response, decreased hyperplastic lesions, and blocked tumor progression from premalignant to a malignant stage. Our data showed that the strategy to block the androgenic and PI3K/AKT/mTOR pathway is an effective therapeutic option and should be investigated including distinct PI3K pathway inhibitors.

Multiplicity of acquired cross-resistance in paclitaxel-resistant cancer cells is associated with feedback control of TUBB3 via FOXO3a-mediated ABCB1 regulation

Acquired drug resistance is a primary obstacle for effective cancer therapy. The correlation of point mutations in class III β-tubulin (TUBB3) and the prominent overexpression of ATP-binding cassette P-glycoprotein (ABCB1), a multidrug resistance gene, have been protruding mechanisms of resistance to microtubule disruptors such as paclitaxel (PTX) for many cancers. However, the precise underlying mechanism of the rapid onset of cross-resistance to an array of structurally and functionally unrelated drugs in PTX-resistant cancers has been poorly understood. We determined that our established PTX-resistant cancer cells display ABCB1/ABCC1-associated cross-resistance to chemically different drugs such as 5-fluorouracil, docetaxel, and cisplatin. We found that feedback activation of TUBB3 can be triggered through the FOXO3a-dependent regulation of ABCB1, which resulted in the accentuation of induced PTX resistance and encouraged multiplicity in acquired cross-resistance. FOXO3a-directed regulation of P-glycoprotein (P-gp) function suggests that control of ABCB1 involves methylation-dependent activation. Consistently, transcriptional overexpression or downregulation of FOXO3a directs inhibitor-controlled protease-degradation of TUBB3. The functional PI3K/Akt signaling is tightly responsive to FOXO3a activation alongside doxorubicin treatment, which directs FOXO3a arginine hypermethylation. In addition, we found that secretome factors from PTX-resistant cancer cells with acquired cross-resistance support a P-gp-dependent association in multidrug resistance (MDR) development, which assisted the FOXO3a-mediated control of TUBB3 feedback. The direct silencing of TUBB3 reverses induced multiple cross-resistance, reduces drug-resistant tumor mass, and suppresses the impaired microtubule stability status of PTX-resistant cells with transient cross-resistance. These findings highlight the control of the TUBB3 response to ABCB1 genetic suppressors as a mechanism to reverse the profuse development of multidrug resistance in cancer.

FOXA1 expression is a strong independent predictor of early PSA recurrence in ERG negative prostate cancers treated by radical prostatectomy

FOXA1 (Fork-head box protein A1, HNF-3a) is a transcription factor involved in androgen signaling with relevance for lineage-specific gene expression of the prostate. The expression was analyzed by immunohistochemistry on a tissue microarray containing 11152 prostate cancer specimens. Results were compared with tumor phenotype, biochemical recurrence, androgen receptor expression, ETS-related gene (ERG) status and other recurrent genomic alterations. FOXA1 expression was detectable in 97.6% of 8227 interpretable cancers and considered strong in 28.5%, moderate in 46.2% and weak in 22.9% of cases. High FOXA1 expression was associated with TMPRSS2:ERG rearrangement and ERG expression (P < 0.0001). High FOXA1 expression was linked to high Gleason grade, advanced pathological tumor (pT) stage and early PSA recurrence in ERG negative cancers (P < 0.0001), while these associations were either weak or absent in ERG positive cancers. In ERG negative cancers, the prognostic role of FOXA1 expression was independent of Gleason grade, pathological tumor stage, lymph node stage, surgical margin status and preoperative PSA. Independent prognostic value became even more evident if the analysis was limited to preoperatively available features such as biopsy Gleason grade, preoperative PSA, cT stage and FOXA1 expression (P < 0.0001). Within ERG negative cancers, FOXA1 expression was also strongly associated with PTEN and 5q21 deletions (P < 0.0001). High expression of FOXA1 is an independent prognostic parameter in ERG negative prostate cancer. Thus, FOXA1 measurement might provide clinically useful information in prostate cancer.

Androgen Signaling in Prostate Cancer

The androgen-signaling axis plays a pivotal role in the pathogenesis of prostate cancer. Since the landmark discovery by Huggins and Hodges, gonadal depletion of androgens has remained a mainstay of therapy for advanced disease. However, progression to castration-resistant prostate cancer (CRPC) typically follows and is largely the result of restored androgen signaling. Efforts to understand the mechanisms behind CRPC have revealed new insights into dysregulated androgen signaling and intratumoral androgen synthesis, which has ultimately led to the development of several novel androgen receptor (AR)-directed therapies for CRPC. However, emergence of resistance to these newer agents has also galvanized new directions in investigations of prereceptor and postreceptor AR regulation. Here, we review our current understanding of AR signaling as it pertains to the biology and natural history of prostate cancer.

Milk disrupts p53 and DNMT1, the guardians of the genome: implications for acne vulgaris and prostate cancer

There is accumulating evidence that milk shapes the postnatal metabolic environment of the newborn infant. Based on translational research, this perspective article provides a novel mechanistic link between milk intake and milk miRNA-regulated gene expression of the transcription factor p53 and DNA methyltransferase 1 (DNMT1), two guardians of the human genome, that control transcriptional activity, cell survival, and apoptosis. Major miRNAs of milk, especially miRNA-125b, directly target TP53 and complex p53-dependent gene regulatory networks. TP53 regulates the expression of key genes involved in cell homeostasis such as FOXO1, PTEN, SESN1, SESN2, AR, IGF1R, BAK1, BIRC5, and TNFSF10. Nuclear interaction of p53 with DNMT1 controls gene silencing. The most abundant miRNA of milk and milk fat, miRNA-148a, directly targets DNMT1. Reduced DNMT1 expression further attenuates the activity of histone deacetylase 1 (HDAC1) involved in the regulation of chromatin structure and access to transcription. The presented milk-mediated miRNA-p53-DNMT1 pathway exemplified at the promoter regulation of survivin (BIRC5) provides a novel explanation for the epidemiological association between milk consumption and acne vulgaris and prostate cancer. Notably, p53- and DNMT1-targeting miRNAs of bovine and human milk survive pasteurization and share identical seed sequences, which theoretically allows the interaction of bovine miRNAs with the human genome. Persistent intake of milk-derived miRNAs that attenuate p53- and DNMT1 signaling of the human milk consumer may thus present an overlooked risk factor promoting acne vulgaris, prostate cancer, and other p53/DNMT1-related Western diseases. Therefore, bioactive miRNAs of commercial milk should be eliminated from the human food chain.

Isorhapontigenin induced cell growth inhibition and apoptosis by targeting EGFR-related pathways in prostate cancer

Isorhapontigenin (ISO), a naturally phytopolyphenol compound existing in Chinese herb, apples, and various vegetables, has attracted extensive interest in recent years for its diverse pharmacological characteristics. Increasing evidences reveal that ISO can inhibit cancer cell growth by induced apoptosis, however, the molecular mechanisms is not fully understood. In this study, we found for the first time that ISO apparently induced cell growth inhibition and apoptosis by targeting EGFR and its downstream signal pathways in prostate cancer (PCa) cells both in vitro and in vivo, whereas no obviously effect on normal prostate cells. From the results, we found that ISO competitively targeted EGFR with EGF and inhibited EGFR auto-phosphorylation, and then decreased the levels of p-Erk1/2, p-PI3 K, and p-AKT, and further induced down-regulation of p-FOXO1 and promoted FOXO1 nuclear translocation; and finally resulted in a significantly up-regulation of Bim/p21/27/Bax/cleaved Caspase-3/cleaved PARP-1 and a markedly down-regulation of Sp1/Bcl-2/XIAP/Cyclin D1. Moreover, our experimental data demonstrated that treatment of ISO decreased protein level of AR via both inhibiting the expression of AR gene and promoting the ubiquitination/degradation of AR proteins in proteasome. In vivo, we also found that ISO inhibited the growth of subcutaneous xenotransplanted tumor in nude mice by inducing PCa cell growth inhibition and apoptosis. Taken together, all findings here clearly implicated that EGFR-related signal pathways, including EGFR-PI3K-Akt and EGFR-Erk1/2 pathways, were involved in ISO-induced cell growth inhibition and apoptosis in PCa cells, providing a more solid theoretical basis for the application of ISO to treat patients with prostate cancer in clinic.

Cooperation among heterogeneous prostate cancer cells in the bone metastatic niche

The growth of disseminated tumor cells into metastatic lesions depends on the establishment of a favorable microenvironment in the stroma of the target organs. Here we show that mice treated with anakinra, an antagonist of the interleukin (IL)-1β receptor (IL-1R), or harboring a targeted deletion of IL-1R are significantly less prone to develop bone tumors when inoculated in the arterial circulation with human prostate cancer (PCa) cells expressing IL-1β. Interestingly, human mesenchymal stem cells exposed in vitro to medium conditioned by IL-1β-expressing cancer cells responded by upregulating S100A4, a marker of cancer-associated fibroblasts (CAFs), and this effect was blocked by anakinra. Analogously, the stroma adjacent to skeletal metastases generated in mice by IL-1β-expressing cancer cells showed a dramatic increase in S100A4, COX-2 and the alteration of 30 tumor-related genes as measured by Nanostring analysis. These effects were not observed in the stroma associated with the rare and much smaller metastases generated by the same cells in IL-1R knockout animals, confirming that tumor-secreted IL-1β generates skeletal CAFs and conditions the surrounding bone microenvironment. In skeletal lesions from patients with metastatic PCa, histological and molecular analyses revealed that IL-1β is highly expressed in cancer cells in which the androgen receptor (AR) is not detected (AR-), whereas this cytokine is uniformly absent in the AR-positive (AR+) metastatic cells. The stroma conditioned by IL-1β-expressing cancer cells served as a supportive niche also for coexisting IL-1β-lacking cancer cells, which are otherwise unable to generate tumors after independently seeding the skeleton of mice. This niche is established very early following tumor seeding and hints to a role of IL-1β in promoting early colonization of PCa at the skeletal level.

Src promotes castration-recurrent prostate cancer through androgen receptor-dependent canonical and non-canonical transcriptional signatures

Progression of prostate cancer (PC) to castration-recurrent growth (CRPC) remains dependent on sustained expression and transcriptional activity of the androgen receptor (AR). A major mechanism contributing to CRPC progression is through the direct phosphorylation and activation of AR by Src-family (SFK) and ACK1 tyrosine kinases. However, the AR-dependent transcriptional networks activated by Src during CRPC progression have not been elucidated. Here, we show that activated Src (Src527F) induces androgen-independent growth in human LNCaP cells, concomitant with its ability to induce proliferation/survival genes normally induced by dihydrotestosterone (DHT) in androgen-dependent LNCaP and VCaP cells. Src induces additional gene signatures unique to CRPC cell lines, LNCaP-C4-2 and CWR22Rv1, and to CRPC LuCaP35.1 xenografts. By comparing the Src-induced AR-cistrome and/or transcriptome in LNCaP to those in CRPC and LuCaP35.1 tumors, we identified an 11-gene Src-regulated CRPC signature consisting of AR-dependent, AR binding site (ARBS)-associated genes whose expression is altered by DHT in LNCaP[Src527F] but not in LNCaP cells. The differential expression of a subset (DPP4, BCAT1, CNTNAP4, CDH3) correlates with earlier PC metastasis onset and poorer survival, with the expression of BCAT1 required for Src-induced androgen-independent proliferation. Lastly, Src enhances AR binding to non-canonical ARBS enriched for FOXO1, TOP2B and ZNF217 binding motifs; cooperative AR/TOP2B binding to a non-canonical ARBS was both Src- and DHT-sensitive and correlated with increased levels of Src-induced phosphotyrosyl-TOP2B. These data suggest that CRPC progression is facilitated via Src-induced sensitization of AR to intracrine androgen levels, resulting in the engagement of canonical and non-canonical ARBS-dependent gene signatures.

Differential expression of miR-34b and androgen receptor pathway regulate prostate cancer aggressiveness between African-Americans and Caucasians

African-Americans are diagnosed with more aggressive prostate cancers and have worse survival than Caucasians, however a comprehensive understanding of this health disparity remains unclear. To clarify the mechanisms leading to this disparity, we analyzed the potential involvement of miR-34b expression in African-Americans and Caucasians. miR-34b functions as a tumor suppressor and has a multi-functional role, through regulation of cell proliferation, cell cycle and apoptosis. We found that miR-34b expression is lower in human prostate cancer tissues from African-Americans compared to Caucasians. DNA hypermethylation of the miR-34b-3p promoter region showed significantly higher methylation in prostate cancer compared to normal samples. We then sequenced the promoter region of miR-34b-3p and found a chromosomal deletion in miR-34b in African-American prostate cancer cell line (MDA-PCA-2b) and not in Caucasian cell line (DU-145). We found that AR and ETV1 genes are differentially expressed in MDA-PCa-2b and DU-145 cells after overexpression of miR-34b. Direct interaction of miR-34b with the 3' untranslated region of AR and ETV1 was validated by luciferase reporter assay. We found that miR-34b downregulation in African-Americans is inversely correlated with high AR levels that lead to increased cell proliferation. Overexpression of miR-34b in cell lines showed higher inhibition of cell proliferation, apoptosis and G1 arrest in the African-American cells (MDA-PCa-2b) compared to Caucasian cell line (DU-145). Taken together, our results show that differential expression of miR-34b and AR are associated with prostate cancer aggressiveness in African-Americans.

Forkhead transcription factor 1 inhibits endometrial cancer cell proliferation via sterol regulatory element-binding protein 1

The morbidity and mortality associated with endometrial cancer (EC) has increased in recent years. Regarded as a tumor suppressor, forkhead transcription factor 1 (FOXO1) has various biological activities and participates in cell cycle progression, apoptosis and differentiation. Notably, FOXO1 also functions in the regulation of lipogenesis and energy metabolism. Lipogenesis is a feature of cancer and is upregulated in EC. Sterol regulatory element-binding protein 1 (SREBP1) is a transcription factor that is also able to regulate lipogenesis. Increased expression of SREBP1 is directly correlated with malignant transformation of tumors. A previous study demonstrated that SREBP1 was highly expressed in EC and directly resulted in tumorigenesis. However, the association between FOXO1 and SREBP1 in EC is not clear. In the present study, lentiviruses overexpressing FOXO1 were used in cell transfection and transduction. Cell viability assays demonstrated that the overexpression of FOXO1 was able to suppress cell proliferation significantly in Ishikawa and AN3 CA cell lines. In addition, FOXO1 overexpression significantly inhibited cell migration and invasion ability in vitro. In xenograft models, overexpression of FOXO1 suppressed cell tumorigenesis, and western blot analysis demonstrated that SREBP1 expression was markedly reduced in the FOXO1-overexpressing cells. It may therefore be concluded that FOXO1 is able to inhibit the proliferative capacity of cells in vitro and in vivo, in addition to the migratory and invasive capacities in vitro by directly targeting SREBP1.

Androgen-glucocorticoid interactions in the era of novel prostate cancer therapy

Great strides have been made in the treatment of castration-resistant prostate cancer (CRPC) with the development of new antiandrogens (enzalutamide) and more potent androgen synthesis inhibitors (abiraterone) that have both improved patient outcomes. These new drugs have also helped unravel the complex biology of androgen-androgen receptor driven prostate cancer and brought into prominence various mechanisms triggering the development of drug resistance and tumour cell survival despite use of androgen deprivation therapy (ADT). The complex role of glucocorticoids in the treatment, management and progression of patients with CRPC is integral to these advances. Historically, glucocorticoid treatment has resulted in both subjective and objective responses in patients with advanced-stage prostate cancer. With the use of these new therapeutic agents, however, unexpected glucocorticoid-related mechanisms that can cause iatrogenic stimulation of prostate cancer growth have emerged, which might contribute to drug resistance and disease progression despite optimal ADT. For example, the upregulation of glucocorticoid receptors (GRs) during enzalutamide therapy results in glucocorticoid-GR-mediated regulation of androgen target genes, leading to escape from enzalutamide blockade. Thus, understanding the biological role of glucocorticoids in patients with prostate cancer is of major importance in the era of new and evolving antiandrogen therapies.

Deep sequencing of small RNA libraries from human prostate epithelial and stromal cells reveal distinct pattern of microRNAs primarily predicted to target growth factors

Complex epithelial and stromal cell interactions are required during the development and progression of prostate cancer. Regulatory small non-coding microRNAs (miRNAs) participate in the spatiotemporal regulation of messenger RNA (mRNA) and regulation of translation affecting a large number of genes involved in prostate carcinogenesis. In this study, through deep-sequencing of size fractionated small RNA libraries we profiled the miRNAs of prostate epithelial (PrEC) and stromal (PrSC) cells. Over 50 million reads were obtained for PrEC in which 860,468 were unique sequences. Similarly, nearly 76 million reads for PrSC were obtained in which over 1 million were unique reads. Expression of many miRNAs of broadly conserved and poorly conserved miRNA families were identified. Sixteen highly expressed miRNAs with significant change in expression in PrSC than PrEC were further analyzed in silico. ConsensusPathDB showed the target genes of these miRNAs were significantly involved in adherence junction, cell adhesion, EGRF, TGF-β and androgen signaling. Let-7 family of tumor-suppressor miRNAs expression was highly pervasive in both, PrEC and PrSC cells. In addition, we have also identified several miRNAs that are unique to PrEC or PrSC cells and their predicted putative targets are a group of transcription factors. This study provides perspective on the miRNA expression in PrEC and PrSC, and reveals a global trend in miRNA interactome. We conclude that the most abundant miRNAs are potential regulators of development and differentiation of the prostate gland by targeting a set of growth factors. Additionally, high level expression of the most members of let-7 family miRNAs suggests their role in the fine tuning of the growth and proliferation of prostate epithelial and stromal cells.

Benzyl isothiocyanate inhibits breast cancer cell tumorigenesis via repression of the FoxH1-Mediated Wnt/β-catenin pathway

The mechanisms underlying the growth inhibitory effect of Benzyl isothiocyanate (BITC) against breast cancer are still not fully understood. Therefore, we further investigated the mechanism in BITC triggering breast cancer. In the present study, we found that the overexpression of FOXH1 in breast cancers tissues and cells, and FOXH1 significantly promoted cell proliferation, invasion and tumorigenesis in vitro. FOXH1 significantly increased the expression levels of β-catenin, cyclinD1, and c-myc proteins in breast cancer cells. Furthermore, siβ-catenin reduced FOXH1 promotion of cell proliferation and invasion in breast cancer cells. Taken together, these results suggest that FOXH1 promoted breast cancer cell growth and invasion by potentiating the Wnt/β-catenin pathway, suggesting that FOXH1 may be a potential molecular target for breast cancer prevention and therapy. Furthermore, BITC treatment has remarkable effect on the expression level of FOXH1 and β-catenin mRNA and protein in MCF-7 cells, MDA-MB-231 cells and SUM 159 cells. BITC treatment has an obvious significance on transcriptional activity of FOXH1. Cell growth and invasion inhibition resulting from BITC exposure were significantly augmented by FoxH1 knockdown. In conclusion, the present study provides novel insights into the molecular circuitry of BITC-induced cell death involving FoxH1-mediated tumorigenesis. Thus, the present study provides a novel insight into the underlying mechanism of tumorigenesis in BITC triggering breast cancer, indicating the therapeutic potential of FOXH1 in the treatment of breast cancer.

FOXA1 regulates androgen receptor variant activity in models of castrate-resistant prostate cancer

Retention of androgen receptor (AR) signalling in castrate-resistant prostate cancer (CRPC) highlights the requirement for the development of more effective AR targeting therapies. A key mechanism of resistance to anti-androgens is through expression of constitutively active AR variants (AR-Vs) that are refractory to next-generation therapies, including Enzalutamide and Abiraterone. By maintaining an androgenic gene signature, AR-Vs drive tumour survival and progression in castrate conditions. Critically, however, our understanding of the mechanics of AR-V-driven transcription is limited, particularly with respect to dependency on pioneer factor function. Here we show that depletion of FOXA1 in the CWR22Rv1 CRPC cell line abrogates the oncogenic potential of AR-Vs. Gene expression profiling reveals that approximately 41% of the AR-V transcriptome requires FOXA1 and that depletion of FOXA1 attenuates AR-V binding at a sub-set of analysed co-regulated genes. Interestingly, AR-V levels are elevated in cells depleted of FOXA1 as a consequence of attenuated negative feedback on the AR gene, but is insufficient to maintain cell growth as evidenced by marked anti-proliferative effects in FOXA1 knockdown cells. In all, our data suggests that AR-Vs are dependent on FOXA1 for sustaining a pro-proliferative gene signature and agents targeting FOXA1 may represent novel therapeutic options for CRPC patients.

Linking diet to acne metabolomics, inflammation, and comedogenesis: an update

Acne vulgaris, an epidemic inflammatory skin disease of adolescence, is closely related to Western diet. Three major food classes that promote acne are: 1) hyperglycemic carbohydrates, 2) milk and dairy products, 3) saturated fats including trans-fats and deficient ω-3 polyunsaturated fatty acids (PUFAs). Diet-induced insulin/insulin-like growth factor (IGF-1)-signaling is superimposed on elevated IGF-1 levels during puberty, thereby unmasking the impact of aberrant nutrigenomics on sebaceous gland homeostasis. Western diet provides abundant branched-chain amino acids (BCAAs), glutamine, and palmitic acid. Insulin and IGF-1 suppress the activity of the metabolic transcription factor forkhead box O1 (FoxO1). Insulin, IGF-1, BCAAs, glutamine, and palmitate activate the nutrient-sensitive kinase mechanistic target of rapamycin complex 1 (mTORC1), the key regulator of anabolism and lipogenesis. FoxO1 is a negative coregulator of androgen receptor, peroxisome proliferator-activated receptor-γ (PPARγ), liver X receptor-α, and sterol response element binding protein-1c (SREBP-1c), crucial transcription factors of sebaceous lipogenesis. mTORC1 stimulates the expression of PPARγ and SREBP-1c, promoting sebum production. SREBP-1c upregulates stearoyl-CoA- and Δ6-desaturase, enhancing the proportion of monounsaturated fatty acids in sebum triglycerides. Diet-mediated aberrations in sebum quantity (hyperseborrhea) and composition (dysseborrhea) promote Propionibacterium acnes overgrowth and biofilm formation with overexpression of the virulence factor triglyceride lipase increasing follicular levels of free palmitate and oleate. Free palmitate functions as a "danger signal," stimulating toll-like receptor-2-mediated inflammasome activation with interleukin-1β release, Th17 differentiation, and interleukin-17-mediated keratinocyte proliferation. Oleate stimulates P. acnes adhesion, keratinocyte proliferation, and comedogenesis via interleukin-1α release. Thus, diet-induced metabolomic alterations promote the visible sebofollicular inflammasomopathy acne vulgaris. Nutrition therapy of acne has to increase FoxO1 and to attenuate mTORC1/SREBP-1c signaling. Patients should balance total calorie uptake and restrict refined carbohydrates, milk, dairy protein supplements, saturated fats, and trans-fats. A paleolithic-like diet enriched in vegetables and fish is recommended. Plant-derived mTORC1 inhibitors and ω-3-PUFAs are promising dietary supplements supporting nutrition therapy of acne vulgaris.