Evolution of the Androgen Receptor Pathway during Progression of Prostate Cancer

1H-NMR-based urine metabolomics of prostate cancer and benign prostatic hyperplasia

Background

Prostate cancer (PCa) and benign prostatic hyperplasia (BPH) are prevalent conditions affecting a significant portion of the male population, particularly with advancing age. Traditional diagnostic methods, such as digital rectal examination (DRE) and prostate-specific antigen (PSA) tests, have limitations in specificity and sensitivity, leading to potential overdiagnosis and unnecessary biopsies.

Significance

This study explores the effectiveness of 1H NMR urine metabolomics in distinguishing PCa from BPH and in differentiating various PCa grades, presenting a non-invasive diagnostic alternative with the potential to enhance early detection and patient-specific treatment strategies.

Results

The study demonstrated the capability of 1H NMR urine metabolomics in detecting distinct metabolic profiles between PCa and BPH, as well as among different Gleason grade groups. Notably, this method surpassed the PSA test in distinguishing PCa from BPH. Untargeted metabolomics analysis also revealed several metabolites with varying relative concentrations between PCa and BPH cases, suggesting potential biomarkers for these conditions.

DHCR24 in Tumor Diagnosis and Treatment: A Comprehensive Review

As an important nutrient in the human body, cholesterol can not only provide structural components for the body's cells, but also can be transformed into a variety of active substances to regulate cell signaling pathways. As an important cholesterol synthase, DHCR24 participates in important regulatory processes in the body. The application of DHCR24 in tumor clinical diagnosis and treatment also attracts much attention. This article reviews the structure and regulatory characteristics of DHCR24, and the research of DHCR24 on tumor progression. We summarize the possible mechanisms of DHCR24 promoting tumor progression through reactive oxygen species (ROS), p53, Ras and PI3K-AKT pathways. Through our review, we hope to provide more research ideas and reference value for the application of DHCR24 in tumor prevention and treatment.

The mutational landscape of a US Midwestern breast cancer cohort reveals subtype-specific cancer drivers and prognostic markers

BACKGROUND

Female breast cancer remains the second leading cause of cancer-related death in the USA. The heterogeneity in the tumor morphology across the cohort and within patients can lead to unpredictable therapy resistance, metastasis, and clinical outcome. Hence, supplementing classic pathological markers with intrinsic tumor molecular markers can help identify novel molecular subtypes and the discovery of actionable biomarkers.

METHODS

We conducted a large multi-institutional genomic analysis of paired normal and tumor samples from breast cancer patients to profile the complex genomic architecture of breast tumors. Long-term patient follow-up, therapeutic regimens, and treatment response for this cohort are documented using the Breast Cancer Collaborative Registry. The majority of the patients in this study were at tumor stage 1 (51.4%) and stage 2 (36.3%) at the time of diagnosis. Whole-exome sequencing data from 554 patients were used for mutational profiling and identifying cancer drivers.

RESULTS

We identified 54 tumors having at least 1000 mutations and 185 tumors with less than 100 mutations. Tumor mutational burden varied across the classified subtypes, and the top ten mutated genes include MUC4, MUC16, PIK3CA, TTN, TP53, NBPF10, NBPF1, CDC27, AHNAK2, and MUC2. Patients were classified based on seven biological and tumor-specific parameters, including grade, stage, hormone receptor status, histological subtype, Ki67 expression, lymph node status, race, and mutational profiles compared across different subtypes. Mutual exclusion of mutations in PIK3CA and TP53 was pronounced across different tumor grades. Cancer drivers specific to each subtype include TP53, PIK3CA, CDC27, CDH1, STK39, CBFB, MAP3K1, and GATA3, and mutations associated with patient survival were identified in our cohort.

CONCLUSIONS

This extensive study has revealed tumor burden, driver genes, co-occurrence, mutual exclusivity, and survival effects of mutations on a US Midwestern breast cancer cohort, paving the way for developing personalized therapeutic strategies.

Identification of a m6A-related ferroptosis signature as a potential predictive biomarker for lung adenocarcinoma

BACKGROUND

Both N6-methyladenosine (m⁶A) and ferroptosis-related genes are associated with the prognosis of lung adenocarcinoma. However, the predictive value of m⁶A-related ferroptosis genes remains unclear. Here, we aimed to identify the prognostic value of m⁶A-related ferroptosis genes in lung adenocarcinoma.

METHODS

Lung adenocarcinoma sample data were downloaded from the University of California Santa Cruz Xena and Gene Expression Omnibus databases. Spearman's correlation analysis was used to screen for m⁶A-related ferroptosis genes. Univariate Cox regression, Kaplan-Meier, and Lasso analyses were conducted to identify prognostic m⁶A-related ferroptosis genes, and stepwise regression was used to construct a prognostic gene signature. The predictive value of the gene signature was assessed using a multivariate Cox analysis. In the validation cohort, survival analysis was performed to verify gene signature stability. The training cohort was divided into high- and low-risk groups according to the median risk score to assess differences between the two groups in terms of gene set variation analysis, somatic mutations, and tumor immune infiltration cells.

RESULTS

Six m⁶A-related ferroptosis genes were used to construct a gene signature in the training cohort and a multivariate Cox analysis was conducted to determine the independent prognostic value of these genes in lung adenocarcinoma. In the validation cohort, Kaplan-Meier and receiver operating characteristic analyses confirmed the strong predictive power of this signature for the prognosis of lung adenocarcinoma. Gene set variation analysis showed that the low-risk group was mainly related to immunity, and the high-risk group was mainly related to DNA replication. Somatic mutation analysis revealed that the TP53 gene had the highest mutation rate in the high-risk group. Tumor immune infiltration cell analysis showed that the low-risk group had higher levels of resting CD4 memory T cells and lower levels of M0 macrophages.

CONCLUSION

Our study identified a novel m⁶A-related ferroptosis-associated six-gene signature (comprising SLC2A1, HERPUD1, EIF2S1, ACSL3, NCOA4, and CISD1) for predicting lung adenocarcinoma prognosis, yielding a useful prognostic biomarker and potential therapeutic target.

HERPUD1 promotes ovarian cancer cell survival by sustaining autophagy and inhibit apoptosis via PI3K/AKT/mTOR and p38 MAPK signaling pathways

HERPUD1 is an important early marker of endoplasmic reticulum stress (ERS) and is involved in the ubiquitination and degradation of several unfolded proteins. However, its role in tumorigenesis is seldom studied, and its role in ovarian cancer is unclear. Lewis y antigen is a tumor-associated sugar antigen that acts as an 'antenna' on the cell surface to receive signals from both inside and outside the cell. We previously reported that Lewis y can promote ovarian cancer by promoting autophagy and inhibiting apoptosis. In this study, we detect the expression of HERPUD1 and Lewis y antigens in 119 different ovarian cancer tissues, determine their relationship with clinicopathological parameters, analyze the correlation between these two proteins, and explore the related cancer-promoting mechanisms through MTT, flow cytometry, western blotting, and bioinformatics. HERPUD1 is highly expressed in ovarian cancer, especially in the early stage, and the expression of HERPUD1 and Lewis y antigen was positively correlated. After overexpression of Lewis y antigen, the expression level of HERPUD1 increased. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathways (KEGG) analysis showed that HERPUD1 and its related genes are enriched in regulating immunity, endoplasmic reticulum stress, ubiquitin-dependent degradation, ERS-induced apoptosis, and other key signaling pathways. We also clarified the HERPUD1 network of kinases, microRNA and transcription factor targets, and the impact of HERPUD1 mutations on prognosis. In addition, HERPUD1 promotes the proliferation of ovarian cancer cells, inhibits apoptosis, affects the cell cycle, promotes the occurrence of autophagy, and inhibits EMT and PI3K/AKT/mTOR and p38MAPK pathways. Overall, HERPUD1, regulated by the expression of tumor-associated protein Lewis y, promotes cell survival in the early stages of tumors, suggesting that HERPUD1 may play an important role in the development of ovarian cancer.

Progression of prostate cancer reprograms MYC-mediated lipid metabolism via lysine methyltransferase 2A

BACKGROUND

The activities of MYC, the androgen receptor, and its associated pioneer factors demonstrate substantial reprogramming between early and advanced prostate cancer. Although previous studies have shown a shift in cellular metabolic requirements associated with prostate cancer progression, the epigenetic regulation of these processes is incompletely described. Here, we have integrated chromatin immunoprecipitation sequencing (ChIP-seq) and whole-transcriptome sequencing to identify novel regulators of metabolism in advanced prostate tumors characterized by elevated MYC activity.

RESULTS

Using ChIP-seq against MYC, HOXB13, and AR in LNCaP cells, we observed redistribution of co-bound sites suggestive of differential KMT2A activity as a function of MYC expression. In a cohort of 177 laser-capture microdissected foci of prostate tumors, KMT2A expression was positively correlated with MYC activity, AR activity, and HOXB13 expression, but decreased with tumor grade severity. However, KMT2A expression was negatively correlated with these factors in 25 LuCaP patient-derived xenograft models of advanced prostate cancer and 99 laser-capture microdissected foci of metastatic castration-resistant prostate cancer. Stratified by KMT2A expression, ChIP-seq against AR and HOXB13 in 15 LuCaP patient-derived xenografts showed an inverse association with sites involving genes implicated in lipid metabolism, including the arachidonic acid metabolic enzyme PLA2G4F. LuCaP patient-derived xenograft models grown as organoids recapitulated the inverse association between KMT2A expression and fluorine-18 labeled arachidonic acid uptake in vitro.

CONCLUSIONS

Our study demonstrates that the epigenetic activity of transcription factor oncogenes exhibits a shift during prostate cancer progression with distinctive phenotypic effects on metabolism. These epigenetically driven changes in lipid metabolism may serve as novel targets for the development of novel imaging agents and therapeutics.

Establishment of a five-enzalutamide-resistance-related-gene-based classifier for recurrence-free survival predicting of prostate cancer

To identify prostate cancer (PCa) patients with a high risk of recurrence is critical before delivering adjuvant treatment. We developed a classifier based on the Enzalutamide treatment resistance‐related genes to assist the currently available staging system in predicting the recurrence‐free survival (RFS) prognosis of PCa patients. We overlapped the DEGs from two datasets to obtain a more convincing Enzalutamide‐resistance‐related‐gene (ERRG) cluster. The five‐ERRG‐based classifier obtained good predictive values in both the training and validation cohorts. The classifier precisely predicted RFS of patients in four cohorts, independent of patient age, pathological tumour stage, Gleason score and PSA levels. The classifier and the clinicopathological factors were combined to construct a nomogram, which had an increased predictive accuracy than that of each variable alone. Besides, we also compared the differences between high‐ and low‐risk subgroups and found their differences were enriched in cancer progression‐related pathways. The five‐ERRG‐based classifier is a practical and reliable predictor, which adds value to the existing staging system for predicting the RFS prognosis of PCa after radical prostatectomy, enabling physicians to make more informed treatment decisions concerning adjuvant therapy.

DAB2IP regulates intratumoral testosterone synthesis and CRPC tumor growth by ETS1/AKR1C3 signaling

The intratumoral androgen synthesis is one of the mechanisms by which androgen receptor (AR) is aberrantly re-activated in castration-resistant prostate cancer (CRPC) after androgen ablation. However, pathways controlling steroidogenic enzyme expression and de novo androgen synthesis in prostate cancer (PCa) cells are largely unknown. In this study, we explored the potential roles of DAB2IP in testosterone synthesis and CRPC tumor growth. Indeed, DAB2IP loss could maintain AR transcriptional activity, PSA re-expression and tumor growth under castrated condition in vitro and in vivo, and reprogram the expression profiles of steroidogenic enzymes, including AKR1C3. Mechanistically, DAB2IP could dramatically inhibit the AKR1C3 promoter activity and the conversion from androgen precursors (i.e., DHEA) to testosterone through PI3K/AKT/mTOR/ETS1 signaling. Consistently, there was a high co-expression of ETS1 and AKR1C3 in PCa tissues and xenografts, and their expression in prostate tissues could also restore AR nuclear staining in castrated DAB2IP-/- mice after DHEA supplement. Together, this study reveals a novel regulation of intratumoral de novo androgen synthesis in CRPC, and provides the DAB2IP/ETS1/AKR1C3 signaling as a potential therapeutic target.

Patterns of indolence in prostate cancer (Review)

Although prostate cancer is a major cause of cancer-related mortality worldwide, most patients will have a relatively indolent clinical course. Contrary to most other types of cancer, even the diagnosis of locally advanced or metastatic disease is not always lethal. The present review aimed to summarize what is known regarding the underlying mechanisms related to the indolent course of subsets of prostate cancer, at various stages. The data suggested that no specific gene alteration by itself was responsible for carcinogenesis or disease aggressiveness. However, pathway analysis identified genetic aberrations in multiple critical pathways that tend to accumulate over the course of the disease. The progression from indolence into aggressive disease is associated with a complex interplay in which genetic and epigenetic factors are involved. The effect of the immune tumor microenvironment is also very important. Emerging evidence has suggested that the upregulation of pathways related to cellular aging and senescence can identify patients with indolent disease. In addition, a number of tumors enter a long-lasting quiescent state. Further research will determine whether halting tumor evolution is a feasible option, and whether the life of patients can be markedly prolonged by inducing tumor senescence or long-term dormancy.

Cellular specificity of androgen receptor, coregulators, and pioneer factors in prostate cancer

Androgen signalling, through the transcription factor androgen receptor (AR), is vital to all stages of prostate development and most prostate cancer progression. AR signalling controls differentiation, morphogenesis, and function of the prostate. It also drives proliferation and survival in prostate cancer cells as the tumour progresses; given this importance, it is the main therapeutic target for disseminated disease. AR is also essential in the surrounding stroma, for the embryonic development of the prostate and controlling epithelial glandular development. Stromal AR is also important in cancer initiation, regulating paracrine factors that excite cancer cell proliferation, but lower stromal AR expression correlates with shorter time to progression/worse outcomes. The profile of AR target genes is different between benign and cancerous epithelial cells, between castrate-resistant prostate cancer cells and treatment-naïve cancer cells, between metastatic and primary cancer cells, and between epithelial cells and fibroblasts. This is also true of AR DNA-binding profiles. Potentially regulating the cellular specificity of AR binding and action are pioneer factors and coregulators, which control and influence the ability of AR to bind to chromatin and regulate gene expression. The expression of these factors differs between benign and cancerous cells, as well as throughout disease progression. The expression profile is also different between fibroblast and mesenchymal cell types. The functional importance of coregulators and pioneer factors in androgen signalling makes them attractive therapeutic targets, but given the contextual expression of these factors, it is essential to understand their roles in different cancerous and cell-lineage states.

Fusion transcripts and their genomic breakpoints in polyadenylated and ribosomal RNA-minus RNA sequencing data

BACKGROUND

Fusion genes are typically identified by RNA sequencing (RNA-seq) without elucidating the causal genomic breakpoints. However, non-poly(A)-enriched RNA-seq contains large proportions of intronic reads that also span genomic breakpoints.

RESULTS

We have developed an algorithm, Dr. Disco, that searches for fusion transcripts by taking an entire reference genome into account as search space. This includes exons but also introns, intergenic regions, and sequences that do not meet splice junction motifs. Using 1,275 RNA-seq samples, we investigated to what extent genomic breakpoints can be extracted from RNA-seq data and their implications regarding poly(A)-enriched and ribosomal RNA-minus RNA-seq data. Comparison with whole-genome sequencing data revealed that most genomic breakpoints are not, or minimally, transcribed while, in contrast, the genomic breakpoints of all 32 TMPRSS2-ERG-positive tumours were present at RNA level. We also revealed tumours in which the ERG breakpoint was located before ERG, which co-existed with additional deletions and messenger RNA that incorporated intergenic cryptic exons. In breast cancer we identified rearrangement hot spots near CCND1 and in glioma near CDK4 and MDM2 and could directly associate this with increased expression. Furthermore, in all datasets we find fusions to intergenic regions, often spanning multiple cryptic exons that potentially encode neo-antigens. Thus, fusion transcripts other than classical gene-to-gene fusions are prominently present and can be identified using RNA-seq.

CONCLUSION

By using the full potential of non-poly(A)-enriched RNA-seq data, sophisticated analysis can reliably identify expressed genomic breakpoints and their transcriptional effects.

Transcription factor specificity protein 1-mediated Serine/threonine kinase 39 upregulation promotes the proliferation, migration, invasion and epithelial-mesenchymal transition of hepatocellular carcinoma cells by activating the transforming growth factor-β1 /Smad2/3 pathway

Bioinformatics analysis showed that Serine/threonine kinase 39 (STK39), which was testified to play an important role in human cancers, may be a hub gene in diagnosing hepatocellular carcinoma (HCC). This study aimed to explore whether STK39 could be regulated by specificity protein 1 (SP1) to affect HCC cells malignant processes. Firstly, STK39 expression in tissues of HCC patients and several cell lines was analyzed. After STK39 silencing, cell proliferation was evaluated by methyl thiazolyl tetrazolium and colony formation assay. Tunel staining was used to detect cell apoptosis. Then, the abilities of cell migration and invasion were determined with wound healing and transwell assays. The expression of epithelial-mesenchymal transition (EMT)-related proteins and transforming growth factor-β1 (TGF-β1)/Smad2/3 pathway proteins was tested by western blot analysis. Thereafter, cells were overexpressed with SP1 under the circumstance of STK39 knockdown, and then the above cellular processes were under observation. Results revealed that the increased expression of STK39, which was found in both HHC patients and HCC cell lines, exhibited poor HCC prognosis. STK39 silencing inhibited Hep3b cell proliferation, migration, invasion, EMT and TGF-β1/Smad2/3 expression but promoted cell apoptosis. Additionally, SP1 could bind to the STK39 promoter and facilitate STK39 expression. Further studies revealed that the effects of STK39 silencing on Hep3b cells were blocked by SP1 overexpression. In conclusion, SP1-mediated STK39 up-regulation leads to the increased proliferation, migration, invasion and EMT of HCC cells via activating TGF-β1/Smad2/3 pathway. Therapies that target SP1 to knockdown STK39 expression may contribute to the inhibition of HCC progression.

Gene Regulation Network Analysis on Human Prostate Orthografts Highlights a Potential Role for the JMJD6 Regulon in Clinical Prostate Cancer

Simple Summary

Prostate cancer is a very common malignancy worldwide. Treatment resistant prostate cancer poses a big challenge to clinicians and is the second most common cause of premature death in men with cancer. Gene expression analysis has been performed on clinical tumours but to date none of the gene expression-based biomarkers for prostate cancer have been successfully integrated to into clinical practice to improve patient management and treatment choice. We applied a novel laboratory prostate cancer model to mimic clinical hormone responsive and resistant prostate cancer and tested whether a network of genes similarly regulated by transcription factors (gene products that control the expression of target genes) are associated with patient outcome. We identified regulons (networks of genes similarly regulated) from our preclinical prostate cancer models and further evaluated the top ranked JMJD6 gene related regulated network in three independent clinical patient cohorts.

Abstract

Background: Prostate cancer (PCa) is the second most common tumour diagnosed in men. Tumoral heterogeneity in PCa creates a significant challenge to develop robust prognostic markers and novel targets for therapy. An analysis of gene regulatory networks (GRNs) in PCa may provide insight into progressive PCa. Herein, we exploited a graph-based enrichment score to integrate data from GRNs identified in preclinical prostate orthografts and differentially expressed genes in clinical resected PCa. We identified active regulons (transcriptional regulators and their targeted genes) associated with PCa recurrence following radical prostatectomy. Methods: The expression of known transcription factors and co-factors was analysed in a panel of prostate orthografts (n = 18). We searched for genes (as part of individual GRNs) predicted to be regulated by the highest number of transcriptional factors. Using differentially expressed gene analysis (on a per sample basis) coupled with gene graph enrichment analysis, we identified candidate genes and associated GRNs in PCa within the UTA cohort, with the most enriched regulon being JMJD6, which was further validated in two additional cohorts, namely EMC and ICGC cohorts. Cox regression analysis was performed to evaluate the association of the JMJD6 regulon activity with disease-free survival time in the three clinical cohorts as well as compared to three published prognostic gene signatures (TMCC11, BROMO-10 and HYPOXIA-28). Results: 1308 regulons were correlated to transcriptomic data from the three clinical prostatectomy cohorts. The JMJD6 regulon was identified as the top enriched regulon in the UTA cohort and again validated in the EMC cohort as the top-ranking regulon. In both UTA and EMC cohorts, the JMJD6 regulon was significantly associated with cancer recurrence. Active JMJD6 regulon also correlated with disease recurrence in the ICGC cohort. Furthermore, Kaplan–Meier analysis confirmed shorter time to recurrence in patients with active JMJD6 regulon for all three clinical cohorts (UTA, EMC and ICGC), which was not the case for three published prognostic gene signatures (TMCC11, BROMO-10 and HYPOXIA-28). In multivariate analysis, the JMJD6 regulon status significantly predicted disease recurrence in the UTA and EMC, but not ICGC datasets, while none of the three published signatures significantly prognosticate for cancer recurrence. Conclusions: We have characterised gene regulatory networks from preclinical prostate orthografts and applied transcriptomic data from three clinical cohorts to evaluate the prognostic potential of the JMJD6 regulon.

Role of Non-Coding Regulatory Elements in the Control of GR-Dependent Gene Expression

The glucocorticoid receptor (GR, also known as NR3C1) coordinates molecular responses to stress. It is a potent transcription activator and repressor that influences hundreds of genes. Enhancers are non-coding DNA regions outside of the core promoters that increase transcriptional activity via long-distance interactions. Active GR binds to pre-existing enhancer sites and recruits further factors, including EP300, a known transcriptional coactivator. However, it is not known how the timing of GR-binding-induced enhancer remodeling relates to transcriptional changes. Here we analyze data from the ENCODE project that provides ChIP-Seq and RNA-Seq data at distinct time points after dexamethasone exposure of human A549 epithelial-like cell line. This study aimed to investigate the temporal interplay between GR binding, enhancer remodeling, and gene expression. By investigating a single distal GR-binding site for each differentially upregulated gene, we show that transcriptional changes follow GR binding, and that the largest enhancer remodeling coincides in time with the highest gene expression changes. A detailed analysis of the time course showed that for upregulated genes, enhancer activation persists after gene expression changes settle. Moreover, genes with the largest change in EP300 binding showed the highest expression dynamics before the peak of EP300 recruitment. Overall, our results show that enhancer remodeling may not directly be driving gene expression dynamics but rather be a consequence of expression activation.

New Prognostic Biomarkers in Metastatic Castration-Resistant Prostate Cancer

Prostate cancer is one of the most frequent cancers in men and is a common cause of cancer-related death. Despite significant progress in the diagnosis and treatment of this tumor, patients who relapse after radical treatments inevitably develop metastatic disease. Patient stratification is therefore key in this type of cancer, and there is an urgent need for prognostic biomarkers that can define patients' risk of cancer-related death. In the last 10 years, multiple prognostic factors have been identified and studied. Here, we review the literature available and discuss the most common aberrant genomic pathways in metastatic castration-resistant prostate cancer shown to have a prognostic relevance in this setting.

Knockout of Akt1/2 suppresses the metastasis of human prostate cancer cells CWR22rv1 in vitro and in vivo

Although primary androgen deprivation therapy resulted in tumour regression, unfortunately, majority of prostate cancer progress to a lethal castration‐resistant prostate cancer, finally die to metastasis. The mutual feedback between AKT and AR pathways plays a vital role in the progression and metastasis of prostate cancer. Therefore, the treatment of a single factor will eventually inevitably lead to failure. Therefore, better understanding of the molecular mechanisms underlying metastasis is critical to the development of new and more effective therapeutic agents. In this study, we created prostate cancer CWR22rv1 cells with the double knockout of Akt1 and Akt2 genes through CRISPR/Cas9 method to investigate the effect of Akt in metastasis of prostate cancer. It was found that knockout of Akt1/2 resulted in markedly reduced metastasis in vitro and in vivo, and appeared to interfere AR nuclear translocation through regulating downstream regulatory factor, FOXO proteins. It suggests that some downstream regulatory factors in the AKT and AR interaction network play a vital role in prostate cancer metastasis and are potential targeting molecules for prostate cancer metastasis treatment.

Identification of Hub Genes Associated With Development and Microenvironment of Hepatocellular Carcinoma by Weighted Gene Co-expression Network Analysis and Differential Gene Expression Analysis

A further understanding of the molecular mechanism of hepatocellular carcinoma (HCC) is necessary to predict a patient's prognosis and develop new targeted gene drugs. This study aims to identify essential genes related to HCC. We used the Weighted Gene Co-expression Network Analysis (WGCNA) and differential gene expression analysis to analyze the gene expression profile of GSE45114 in the Gene Expression Omnibus (GEO) database and The Cancer Genome Atlas database (TCGA). A total of 37 overlapping genes were extracted from four groups of results. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) enrichment analyses were performed on the 37 overlapping genes. Then, we used the STRING database to map the protein interaction (PPI) network of 37 overlapping genes. Ten hub genes were screened according to the Maximal Clique Centrality (MCC) score using the Cytohubba plugin of Cytoscape (including FOS, EGR1, EPHA2, DUSP1, IGFBP3, SOCS2, ID1, DUSP6, MT1G, and MT1H). Most hub genes show a significant association with immune infiltration types and tumor stemness of microenvironment in HCC. According to Univariate Cox regression analysis and Kaplan-Meier survival estimation, SOCS2 was positively correlated with overall survival (OS), and IGFBP3 was negatively correlated with OS. Moreover, the expression of IGFBP3 increased with the increase of the clinical stage, while the expression of SOCS2 decreased with the increase of the clinical stage. In conclusion, our findings suggest that SOCS2 and IGFBP3 may play an essential role in the development of HCC and may serve as a potential biomarker for future diagnosis and treatment.

The cyclin-dependent kinases pathway as a target for prostate cancer treatment: rationale and future perspectives

The rapidly expanding scenario of treatment options for patients affected by prostate cancer (PC) is leading to improved outcomes; however, PC still represents one of the most frequent causes of male mortality. Thus, while translational research is trying to unravel the molecular landscape underlying carcinogenesis, disease progression and treatment resistance, several clinical trials are evaluating novel options to further expand therapeutic options. The cyclin-dependent kinases (CDK)-pathway represents a promising therapeutic target for different cancer types; due to the pivotal role of this pathway in the regulation of PC cell cycle, three CDK4/6-inhibitors (abemaciclib, palbociclib and ribociclib) are currently being investigated in several clinical trials. In this paper, we review the current knowledge on CDK-pathway and the mechanism of action of CDK-inhibitors; we discuss the biological rationale for their use in PC and the state of the art of clinical trials focused on the demonstration of their potential role in early or advanced stage, in hormone-sensitive and castration-resistant state. Finally, the potential application of precision oncology for treatment selection in PC is discussed.

Long-Chain Acyl-CoA Synthetase 4-Mediated Fatty Acid Metabolism Sustains Androgen Receptor Pathway-Independent Prostate Cancer

Androgen deprivation therapy has led to elevated cases of androgen receptor (AR) pathway-independent prostate cancer with dysregulated fatty acid metabolism. However, it is unclear how prostate cancer cells sustain dysregulated fatty acid metabolism to drive AR-independent prostate cancer. Long-chain acyl-CoA synthetases (ACSL) catalyze the conversion of fatty acids into fatty acyl-CoAs that are required for fatty acid metabolism. In this study, we demonstrate that expression levels of ACSL3 and 4 were oppositely regulated by androgen-AR signaling in prostate cancer cells. AR served as a transcription suppressor to bind at the ACSL4 promoter region and inhibited its transcription. Inhibition of androgen-AR signaling significantly downregulated ACSL3 and PSA, but elevated ACSL4 levels. ACSL4 regulated a broad spectrum of fatty acyl-CoA levels, and its catalytic efficiency in fatty acyl-CoAs biosynthesis was about 1.9- to 4.3-fold higher than ACSL3. In addition, in contrast to ACSL3, ACSL4 significantly regulated global protein myristoylation or myristoylation of Src kinase in prostate cancer cells. Knockdown of ACSL4 inhibited the proliferation, migration, invasion, and xenograft growth of AR-independent prostate cancer cells. Our results suggest that the surge of ACSL4 levels by targeting AR signaling increases fatty acyl-CoAs biosynthesis and protein myristoylation, indicating the opposite, yet complementary or Yin-Yang regulation of ACSL3 and 4 levels in sustaining fatty acid metabolism when targeting androgen-AR signaling. This study reveals a mechanistic understanding of ACSL4 as a potential therapeutic target for treatment of AR-independent prostate cancer. IMPLICATIONS: AR coordinately regulates the expression of ACSL3 and ACSL4, such that AR pathway-independent prostate tumors become dependent on ACSL4-mediated fatty acid metabolism.

Attenuation of benign prostatic hyperplasia by hydrophilic active compounds from pigmented rice in a testosterone implanted rat model

Benign prostatic hyperplasia (BPH) is a common chronic disease in aging men. The present study aimed to identify the active fraction of a purple rice extract and determine its anti-prostatic hyperplasia effect in a testosterone implanted rat model. The hexane insoluble fraction (HIF) which mainly contains hydrophilic phytochemicals from the purple rice crude ethanolic extract was defined as the active fraction, due to a potent effect on the downregulation of androgen receptor (AR) expression in malignant prostate cells, in addition to low toxicity for normal fibroblast cells. To induce BPH, subcutaneous implanting of a testosterone containing tube was performed in the castrated rats. Oral administration of HIF of at least 0.1 g kg-1 retarded prostate enlargement and improved histological changes induced by testosterone, without any effects on the serum testosterone levels. A lower proliferating cell nuclear antigen (PCNA) labelling index and the downregulated expression of AR, cyclinD1, and fatty acid synthase were clearly observed in the prostates of HIF-fed rats. Additionally, the mRNA levels of inflammation-related cytokines and enzymes in the prostate tissues significantly decreased after HIF treatment. Taken together, these findings demonstrate molecular mechanisms underlying the potential protective effects of the purple rice active fraction against testosterone-induced BPH in rats.

Urine Extracellular Vesicle GATA2 mRNA Discriminates Biopsy Result in Men with Suspicion of Prostate Cancer

PURPOSE

Prostate specific antigen has limited performance in detecting prostate cancer. The transcription factor GATA2 is expressed in aggressive prostate cancer. We analyzed the predictive value of urine extracellular vesicle GATA2 mRNA alone and in combination with a multigene panel to improve detection of prostate cancer and high risk disease.

MATERIALS AND METHODS

GATA2 mRNA was analyzed in matched extracellular vesicles isolated from urines before and after prostatectomy (16) and paired urine and tissue prostatectomy samples (19). Extracellular vesicle GATA2 mRNA performance to distinguish prostate cancer and high grade disease was tested in training (52) and validation (165) cohorts. The predictive value of a multigene score including GATA2, PCA3 and TMPRSS2-ERG (GAPT-E) was tested in both cohorts.

RESULTS

Confirming its prostate origin, urine extracellular vesicle GATA2 mRNA levels decreased significantly after prostatectomy and correlated with prostate cancer tissue GATA2 mRNA levels. In the training and validation cohort GATA2 discriminated prostate cancer (AUC 0.74 and 0.66) and high grade disease (AUC 0.78 and 0.65), respectively. Notably, the GAPT-E score improved discrimination of prostate cancer (AUC 0.84 and 0.72) and high grade cancer (AUC 0.85 and 0.71) in both cohorts when compared with each biomarker alone and PT-E (PCA3 and TMPRSS2-ERG). A GAPT-E score for high grade prostate cancer would avoid 92.1% of unnecessary prostate biopsies, compared to 61.9% when a PT-E score is used.

CONCLUSIONS

Urine extracellular vesicle GATA2 mRNA analysis improves the detection of high risk prostate cancer and may reduce the number of unnecessary biopsies.

LINC00675 activates androgen receptor axis signaling pathway to promote castration-resistant prostate cancer progression

The development of prostate cancer (PCa) from androgen-deprivation therapy (ADT) sensitive to castration resistant (CRPC) seriously impacts life quality and survival of PCa patients. Emerging evidence shows that long noncoding RNAs (lncRNAs) play vital roles in cancer initiation and progression. However, the inherited mechanisms of how lncRNAs participate in PCa progression and treatment resistance remain unclear. Here, we found that a long noncoding RNA LINC00675 was upregulated in androgen-insensitive PCa cell lines and CRPC patients, which promoted PCa progression both in vitro and in vivo. Knockdown of LINC00675 markedly suppressed tumor formation and attenuated enzalutamide resistance of PCa cells. Mechanistically, LINC00675 could directly modulate androgen receptor's (AR) interaction with mouse double minute-2 (MDM2) and block AR's ubiquitination by binding to it. Meanwhile, LINC00675 could bind to GATA2 mRNA and stabilize its expression level, in which GATA2 could act as a co-activator in the AR signaling pathway. Notably, we treated subcutaneous xenografts models with enzalutamide and antisense oligonucleotides (ASO) targeting LINC00675 in vivo and found that targeting LINC00675 would benefit androgen-deprivation-insensitive models. Our findings disclose that the LINC00675/MDM2/GATA2/AR signaling axis is a potential therapeutic target for CRPC patients.

Enzalutamide for the treatment of nonmetastatic castration-resistant prostate cancer

INTRODUCTION

Enzalutamide is the first characterized second-generation nonsteroidal androgen receptor inhibitor (ARi). Its efficacy has been established in several clinical trials evaluating its role in different settings of prostate cancer. Recently, enzalutamide has been approved for the treatment of nonmetastatic castration-resistant prostate cancer (nmCRPC).

AREAS COVERED

In this paper, the authors describe the chemical structure and pharmacologic characteristics of enzalutamide, providing a summary of clinical trials evaluating its efficacy and safety in prostate cancer patients.

EXPERT OPINION

Enzalutamide adds to the growing arsenal of ARi used in nmCRPC. An improvement in metastasis-free survival was observed with the use of these new treatment options; recently released preliminary data report also an OS benefit. These novel agents are generally well tolerated, but their safety profiles differ slightly. Since head-to-head comparisons between ARi in nmCRPC are lacking, the adverse events profile, as well as drug availability, costs, and considerations on treatment-sequencing, would most likely influence the selection of the individual agent in this setting. Further research is needed to improve treatment selection and clarify many unsolved issues. Abbreviations ARi: nonsteroidal androgen receptor inhibitor; nmCRPC: nonmetastatic castration resistant prostate cancer; ADT: androgen deprivation therapy; OS: overall survival; PSA: prostate specific antigen; FDA: Food and Drug Administration; AR: Androgen Receptor; MFS: metastasis free survival; PSA-DT: PSA doubling time; HR: hazard ratio; CI: confidence interval; AEs: adverse events; mCRPC: metastatic castration resistant prostate cancer; mHSPC: metastatic hormone-sensitive prostate cancer; rPFS: radiographic progression-free survival; OR: odds ratio.

Cellular growth factors as prospective therapeutic targets for combination therapy in androgen independent prostate cancer (AIPC)

Cancer is the second leading cause of death worldwide, with prostate cancer, the second most commonly diagnosed cancer among men. Prostate cancer develops in the peripheral zone of the prostate gland, and the initial progression largely depends on androgens, the male reproductive hormone that regulates the growth and development of the prostate gland and testis. The currently available treatments for androgen dependent prostate cancer are, however, effective for a limited period, where the patients show disease relapse, and develop androgen-independent prostate cancer (AIPC). Studies have shown various intricate cellular processes such as, deregulation in multiple biochemical and signaling pathways, intra-tumoral androgen synthesis; AR over-expression and mutations and AR activation via alternative growth pathways are involved in progression of AIPC. The currently approved treatment strategies target a single cellular protein or pathway, where the cells slowly develop resistance and adapt to proliferate via other cellular pathways over a period of time. Therefore, an increased research aims to understand the efficacy of combination therapy, which targets multiple interlinked pathways responsible for acquisition of resistance and survival. The combination therapy is also shown to enhance efficacy as well as reduce toxicity of the drugs. Thus, the present review focuses on the signaling pathways involved in the progression of AIPC, comprising a heterogeneous population of cells and the advantages of combination therapy. Several clinical and pre-clinical studies on a variety of combination treatments have shown beneficial outcomes, yet further research is needed to understand the potential of combination therapy and its diverse strategies.

Biomarkers That Differentiate Benign Prostatic Hyperplasia from Prostate Cancer: A Literature Review

Prediction of prostate cancer in primary care is typically based upon serum total prostate-specific antigen (tPSA) and digital rectal examination results. However, these tests lack sensitivity and specificity, leading to over-diagnosis of disease and unnecessary, invasive biopsies. Therefore, there is a clinical need for diagnostic tests that can differentiate between benign conditions and early-stage malignant disease in the prostate. In this review, we evaluate research papers published from 2009 to 2019 reporting biomarkers that identified or differentiated benign prostatic hyperplasia (BPH) from prostate cancer. Our review identifies hundreds of potential biomarkers in urine, serum, tissue, and semen proposed as useful targets for differentiating between prostate cancer and BPH patients. However, it is still not apparent which of these candidate biomarkers are most useful, and many will not progress beyond the discovery stage unless they are properly validated for clinical practice. We conclude that this validation will come through the use of multivariate panels which can assess the value of biomarker candidates in combination with clinical parameters as part of a risk prediction calculator. Implementation of such a model will help clinicians stratify patients with prostate cancer symptoms in primary care, with tangible benefits for both the patient and the health service.

Simultaneous quantification of oestrogens and androgens in the serum of patients with benign prostatic hyperplasia by liquid chromatography-Tandem mass spectrometry

Benign prostate hyperplasia (BPH) is a common disease in elderly men. It has been found that the occurrence of BPH was closely related to dysregulated steroid hormones. Here, a rapid, sensitive, accurate and specific method for the quantitative profiling of five androgens in man serum was developed and validated by the use of liquid chromatography-tandem mass spectrometry (LC-MS/MS). Using this method, dehydroepiandrosterone (DHEA), androstenedione (A4), testosterone (T), androsterone (A), dihydrotestosterone (DHT), oestrone (E1) and oestradiol (E2) were quantified in serum from man with and without BPH. BPH patients were characterised by the decreases in DHEA, A4 and T as well as increases in DHT, E2 and E1 in serum. Meanwhile, DHEA and DHT in serum were screened as sensitive biomarkers of BPH patients. This study will provide a new perspective of dysregulated steroid hormones for the diagnosis and prevention of BPH.

Cellular rewiring in lethal prostate cancer: the architect of drug resistance

Over the past 5 years, the advent of combination therapeutic strategies has substantially reshaped the clinical management of patients with advanced prostate cancer. However, most of these combination regimens were developed empirically and, despite offering survival benefits, are not enough to halt disease progression. Thus, the development of effective therapeutic strategies that target the mechanisms involved in the acquisition of drug resistance and improve clinical trial design are an unmet clinical need. In this context, we hypothesize that the tumour engineers a dynamic response through the process of cellular rewiring, in which it adapts to the therapy used and develops mechanisms of drug resistance via downstream signalling of key regulatory cascades such as the androgen receptor, PI3K-AKT or GATA2-dependent pathways, as well as initiation of biological processes to revert tumour cells to undifferentiated aggressive states via phenotype switching towards a neuroendocrine phenotype or acquisition of stem-like properties. These dynamic responses are specific for each patient and could be responsible for treatment failure despite multi-target approaches. Understanding the common stages of these cellular rewiring mechanisms to gain a new perspective on the molecular underpinnings of drug resistance might help formulate novel combination therapeutic regimens.

Impact of Benign Prostatic Hyperplasia and/or Prostatitis on the Risk of Prostate Cancer in Korean Patients

Purpose

We evaluated the impact of benign prostatic hyperplasia (BPH) and prostatitis on the risk of prostate cancer (PCa) in patients using nationally representative data of the Korean population from the National Health Insurance Service.

Materials and Methods

A total of 5,580,495 Korean men, aged >20 years, who had undergone health screening in 2009 were followed-up for 9 years until 2017. Multivariate adjusted Cox regression analysis was conducted to determine the hazard ratio (HR) and 95% confidence interval (CI) for the association between BPH and/or prostatitis and PCa. The HR for PCa according to the presence of BPH and/or prostatitis was stratified by a combination of BPH and prostatitis in multivariable-adjusted models.

Results

The HR for PCa significantly increased in patients with BPH and prostatitis than in patients without BPH and prostatitis (adjusted HR, 1.626; 95% CI, 1.567–1.688 and adjusted HR, 1.557; 95% CI, 1.500–1.618, respectively). In particular, for the combination of BPH and prostatitis, the adjusted HR was 1.856 (95% CI, 1.743–1.976), which was the highest when a diagnosis of both BPH and prostatitis was made.

Conclusions

BPH and/or prostatitis are associated with an increased incidence for PCa in Korean patients, which is likely associated with similar effects to prostate-specific antigen (PSA) screening, so care must be taken in the interpretation. However, if follow-up survival studies demonstrate differences between the two groups (BPH and prostatitis vs. general), it could be one of the evidence for the introduction of PSA screening in Korea.

Interleukin-6 signaling pathway involved in major depressive disorder: selective serotonin reuptake inhibitor regulates IL-6 pathway

Background

Evidence indicates that pro-inflammatory Th17 and Th1 cells are involved in major depressive disorder (MDD) pathogenesis. Development of Th17 and Th1 are regulated by IL-6 and IFN-γ, respectively. In this study, the levels of IL-6 and IFN-γ, and mRNA expression of related signaling components and, Th17/Th1 transcription factors were investigated in MDD patients with/without selective serotonin reuptake inhibitor (SSRI) medication.

Materials and methods

Forty-six patients and 38 healthy controls (HCs) were recruited. Twenty patients were received the SSRI (sertraline 50–200 mg/day) for at least 1 year, and 26 patients were not received medication. Expression of IL-6R, IFN-γR, JAK1, JAK2, TYK2, STAT1, STAT3, T-bet and RORγt were assessed with Real-Time-PCR. Serum and supernatant levels of IL-6 and IFN-γ were determined using ELISA.

Results and discussion

The serum and supernatant levels of IL-6 were increased in patients without (SSRI−) compared with HCs, while its levels was reduced in SSRI+. Elevated expressions of IL-6R, STAT3 and RORγt were observed in SSRI− compared with HCs. Expressions of IL-6R, STAT3, RORγt and IFN-γR, were decreased in SSRI+ compared to SSRI− patients.

Conclusion

Increased IL-6 involved in MDD, and SSRI regulates IL-6 pathway and IL-6 production. MDD patients may benefit from IL-6/IL-6R targeted therapeutic intervention.

Androgen receptor enhancer usage and the chromatin regulatory landscape in human prostate cancers

The androgen receptor (AR) is commonly known as a key transcription factor in prostate cancer development, progression and therapy resistance. Genome-wide chromatin association studies revealed that transcriptional regulation by AR mainly depends on binding to distal regulatory enhancer elements that control gene expression through chromatin looping to gene promoters. Changes in the chromatin epigenetic landscape and DNA sequence can locally alter AR-DNA-binding capacity and consequently impact transcriptional output and disease outcome. The vast majority of reports describing AR chromatin interactions have been limited to cell lines, identifying numerous other factors and interacting transcription factors that impact AR chromatin interactions. Do these factors also impact AR cistromics - the genome-wide chromatin-binding landscape of AR - in vivo? Recent technological advances now enable researchers to identify AR chromatin-binding sites and their target genes in human specimens. In this review, we provide an overview of the different factors that influence AR chromatin binding in prostate cancer specimens, which is complemented with knowledge from cell line studies. Finally, we discuss novel perspectives on studying AR cistromics in clinical samples.

Contemporary approach to active surveillance for favorable risk prostate cancer

The approach to favorable risk prostate cancer known as “active surveillance” was first described explicitly in 2002. This was a report of 250 patients managed with a strategy of expectant management, with serial prostate-specific antigen and periodic biopsy, and radical intervention advised for patients who were re-classified as higher risk. This was initiated as a prospective clinical trial, complete with informed consent, beginning in 2007. Thus, there are now 20 years of experience with this approach, which has become widely adopted around the world. In this chapter, we will summarize the biological basis for active surveillance, review the experience to date of the Toronto and Hopkins groups which have reported 15-year outcomes, describe the current approach to active surveillance in patients with Gleason score 3 + 3 or selected patients with Gleason score 3 + 4 with a low percentage of Gleason pattern 4 who may also be candidates, enhanced by the use of magnetic resonance imaging, and forecast future directions.

Androgen receptor functions as transcriptional repressor of cancer-associated fibroblast activation

The aging-associated increase of cancer risk is linked with stromal fibroblast senescence and concomitant cancer-associated fibroblast (CAF) activation. Surprisingly little is known about the role of androgen receptor (AR) signaling in this context. We have found downmodulated AR expression in dermal fibroblasts underlying premalignant skin cancer lesions (actinic keratoses and dysplastic nevi) as well as in CAFs from the 3 major skin cancer types, squamous cell carcinomas (SCCs), basal cell carcinomas, and melanomas. Functionally, decreased AR expression in primary human dermal fibroblasts (HDFs) from multiple individuals induced early steps of CAF activation, and in an orthotopic skin cancer model, AR loss in HDFs enhanced tumorigenicity of SCC and melanoma cells. Forming a complex, AR converged with CSL/RBP-Jκ in transcriptional repression of key CAF effector genes. AR and CSL were positive determinants of each other's expression, with BET inhibitors, which counteract the effects of decreased CSL, restoring AR expression and activity in CAFs. Increased AR expression in these cells overcame the consequences of CSL loss and was by itself sufficient to block the growth and tumor-enhancing effects of CAFs on neighboring cancer cells. As such, the findings establish AR as a target for stroma-focused cancer chemoprevention and treatment.

A designed cell-penetrating human SOCS2 protein suppresses GH-dependent cancer cell proliferation

Suppressor of cytokine signaling (SOCS) 2, a negative regulator of growth hormone (GH) and insulin-like growth factor 1 (IGF-1), which is associated with acromegaly and cancers, is a promising candidate molecule for treating various diseases. To facilitate its use in protein therapy, we designed and constructed a human SOCS2 protein containing a membrane-permeable peptide sequence and expressed it in an Escherichia coli system. The partially purified recombinant protein was effectively delivered into several cancer cell lines and inhibited cell growth. Biochemical analysis showed that the recombinant SOCS2 protein interacted with growth hormone receptor (GHR) and downregulated GH-STAT5 signaling target genes. Our results suggest that the designed cell-penetrating SOCS2 protein will be useful in intercellular protein therapy to cure cancers. Abbreviations: SOCS: suppressor of cytokine signaling; GH: growth hormone; GHR: growth hormone receptor; IGF-1: insulin-like growth factor 1; CP: cell-penetrating; STAT: signal transducer and activator of transcription; JAK: Janus kinase; HNF: hepatocyte nuclear factor; MTM: membrane-translocating motif; HIV: human immunodeficiency virus.

Anti-Proliferative Effects of HBX-5 on Progression of Benign Prostatic Hyperplasia

Benign prostatic hyperplasia (BPH), an age-dependent disorder with a prevalence percentage of 60% in the 60s, has been found to involve an androgenic hormone imbalance that causes confusion between cell apoptosis and proliferation. Because general medications for BPH treatment have undesirable side effects, the development of effective alternative medicines has been considered. HBX-5 is a newly developed formula with the aim of improving BPH, and is composed of nine medicinal herbs. BPH was induced in the rats by intramuscular injection of testosterone propionate after castration. Rats were divided into six groups, and the efficacy of HBX-5 on testosterone-induced BPH in rats was estimated. In addition, RWPE-1 and WPMY-1 cells were used to demonstrate the effect of HBX-5 on BPH in vitro model. Compared with the control group, HBX-5 administration group suppressed BPH manifestations, such as excessive development of prostate, and increase of serum dihydrotestosterone and 5α-reductase concentrations. Furthermore, immunohistochemistry analysis revealed that HBX-5 significantly decreased the expression of androgen receptor (AR) and proliferating cell nuclear antigen (PCNA). In addition, results of RWPE-1 and WPMY-1 cells showed that HBX-5 inhibited the over-expression of AR and PSA in DHT-induced prostate hyperplastic microenvironments.

Paclitaxel Sensitivity of Ovarian Cancer Can be Enhanced by Knocking Down Pairs of Kinases that Regulate MAP4 Phosphorylation and Microtubule Stability

Purpose: Most patients with ovarian cancer receive paclitaxel chemotherapy, but less than half respond. Pre-treatment microtubule stability correlates with paclitaxel response in ovarian cancer cell lines. Microtubule stability can be increased by depletion of individual kinases. As microtubule stability can be regulated by phosphorylation of microtubule-associated proteins (MAPs), we reasoned that depletion of pairs of kinases that regulate phosphorylation of MAPs could induce microtubule stabilization and paclitaxel sensitization.Experimental Design: Fourteen kinases known to regulate paclitaxel sensitivity were depleted individually in 12 well-characterized ovarian cancer cell lines before measuring proliferation in the presence or absence of paclitaxel. Similar studies were performed by depleting all possible pairs of kinases in six ovarian cancer cell lines. Pairs that enhanced paclitaxel sensitivity across multiple cell lines were studied in depth in cell culture and in two xenograft models.Results: Transfection of siRNA against 10 of the 14 kinases enhanced paclitaxel sensitivity in at least six of 12 cell lines. Dual knockdown of IKBKB/STK39 or EDN2/TBK1 enhanced paclitaxel sensitivity more than silencing single kinases. Sequential knockdown was superior to concurrent knockdown. Dual silencing of IKBKB/STK39 or EDN2/TBK1 stabilized microtubules by inhibiting phosphorylation of p38 and MAP4, inducing apoptosis and blocking cell cycle more effectively than silencing individual kinases. Knockdown of IKBKB/STK39 or EDN2/TBK1 enhanced paclitaxel sensitivity in two ovarian xenograft models.Conclusions: Sequential knockdown of dual kinases increased microtubule stability by decreasing p38-mediated phosphorylation of MAP4 and enhanced response to paclitaxel in ovarian cancer cell lines and xenografts, suggesting a strategy to improve primary therapy. Clin Cancer Res; 24(20); 5072-84. ©2018 AACR.

Alterations in the p53-SOCS2 axis contribute to tumor growth in colon cancer

Altered expression of suppressor of cytokine signaling (SOCS) is found in various tumors. However, regulation of SOCS2 by upstream molecules has yet to be clearly elucidated, particularly in tumor cells. SCOCS2 expression was examined in tumor cells transfected with an inducible p53 expression system. The impact of SOCS2 on cell proliferation was measured with in vitro assays. Inhibition of tumorigenicity by SOCS2 knockdown was assessed via a mouse model. Expression profiles were compared and genes differentially expressed were identified using four types of p53-null cells (Saos, HLK3, PC3, and H1299) and the same cells stably expressing p53. Twelve kinds of target genes were simultaneously upregulated or downregulated by p53 in three or more sets of p53-null cells. SOCS2 expression was reciprocally inhibited by inducible p53 expression in p53-null cells, even colon cancer cells. SOCS2 promoter activity was inhibited by wild type but not mutant p53. SOCS2 knockdown inhibited tumor growth in vitro and in an animal xenograph model. SOCS2 overexpression was detected in a murine model of azoxymethane/dextran sulfate sodium-induced colitis-associated colon cancer compared to mock-treated controls. SOCS2 expression was heterogeneously upregulated in some human colon cancers. Thus, SOCS2 was upregulated by p53 dysfunction and seemed to be associated with the tumorigenic potential of colon cancer.

Insights into a signaling protein’s role in cell growth could inform new therapeutic strategies for treating colon cancer. SOCS-2 acts as an ‘off switch’ for cell signaling pathways. It has been identified as possibly protective against many cancers, although some cancers are associated with elevated SOCS-2 levels. Researchers led by Daeghon Kim at Chonbuk National University Hospital in South Korea have now shown that the effects of SOCS-2 are apparently dependent on how much of it is present. Moderate levels of SOCS-2 can suppress growth in colon cancer cells, but Kim’s team showed that excessive SOCS-2 has the opposite effect, promoting proliferation. The researchers also identified a gene commonly mutated in cancer cells that can drive overproduction of SOCS-2. Drugs that inhibit SOCS-2 or block its production may therefore offer useful treatments for colorectal cancer.

STK39 blockage by RNA interference inhibits the proliferation and induces the apoptosis of renal cell carcinoma

Aim

Renal cell carcinoma (RCC), the most frequent type of primary renal malignancies, has a high mortality rate. Serine/threonine kinase 39 (STK39) is associated with various human diseases, including cancers. The current study aimed to investigate the functions of STK39 in RCC.

Materials and methods

STK39 expression levels in RCC and paired normal renal tissue samples were detected by real-time polymerase chain reaction and Western blotting analyses. The biological functions of STK39 were explored in two RCC cell lines with STK39 silence.

Results

STK39 expression was significantly increased in RCC tissues than in normal renal tissues. Suppression of STK39 expression in ACHN and 786-0 cells significantly suppressed cell proliferation and induced cell apoptosis. Consistently, the expression of PCNA and Bcl-2 was remarkably increased, while the expression of Bax was significantly in STK39 knockdown cells compared to control cells. Furthermore, gene set enrichment analysis identified STK39 as an important regulator of p53 and p38 signaling pathways. STK39 knockdown increased p53 expression and inhibited p38 phosphorylation. Moreover, ectopic expression of STK39 in ACHN cells resulted in a reduced p53 expression and increased c-Myc and p-p38 expression. Such effects were suppressed by p38 inhibitor (SB203580).

Conclusion

STK39 may exert its oncogenic function in RCC through p38 signaling. Our data suggest that STK39 may represent a potential therapeutic target against RCC.

Androgen receptor transcriptionally regulates semaphorin 3C in a GATA2-dependent manner

The androgen receptor (AR) is a member of the nuclear receptor superfamily of transcription factors and is central to prostate cancer (PCa) progression. Ligand-activated AR engages androgen response elements (AREs) at androgen-responsive genes to drive the expression of gene batteries involved in cell proliferation and cell fate. Understanding the transcriptional targets of the AR has become critical in apprehending the mechanisms driving treatment-resistant stages of PCa. Although AR transcription regulation has been extensively studied, the signaling networks downstream of AR are incompletely described. Semaphorin 3C (SEMA3C) is a secreted signaling protein with roles in nervous system and cardiac development but can also drive cellular growth and invasive characteristics in multiple cancers including PCa. Despite numerous findings that implicate SEMA3C in cancer progression, regulatory mechanisms governing its expression remain largely unknown. Here we identify and characterize an androgen response element within the SEMA3C locus. Using the AR-positive LNCaP PCa cell line, we show that SEMA3C expression is driven by AR through this element and that AR-mediated expression of SEMA3C is dependent on the transcription factor GATA2. SEMA3C has been shown to promote cellular growth in certain cell types so implicit to our findings is the discovery of direct regulation of a growth factor by AR. We also show that FOXA1 is a negative regulator of SEMA3C. These findings identify SEMA3C as a novel target of AR, GATA2, and FOXA1 and expand our understanding of semaphorin signaling and cancer biology.

Role of high expression levels of STK39 in the growth, migration and invasion of non-small cell type lung cancer cells

Non-small cell type lung cancer (NSCLC) is the most common malignancy and the leading cause of cancer related mortality. In this study, serine/threonine kinase 39 (STK39) was identified as an up-regulated gene in NSCLC tissues by next-generation RNA sequencing. Although STK39 gene polymorphisms may be prognostic of overall survival in patients with early stage NSCLC, the roles of STK39 in NSCLC cancer are poorly understood. In the current study, Genome Set Enrichment Analysis (GSEA) on the RNA-seq data of NSCLC specimens indicated that cancer-related process and pathways, including metastasis, cell cycle, apoptosis and p38 pathway, were significantly correlated with STK39 expression. STK39 expression was significantly increased in NSCLC cases and its protein expression was positively correlated with the poor tumor stage, large tumor size, advanced lymphnode metastasis and poor prognosis. Down-regulation of STK39 in NSCLC cells significantly decreased cell proliferation by blocking of cell cycle and inducing apoptosis. We also found that STK39 knockdown in NSCLC cells remarkably repressed cell migration and invasion. On the contrary, overexpression of STK39 in NSCLC cells had inverse effects on cell behaviors. Taken together, STK39 acts as a tumor oncogene in NSCLC and can be a potential biomarker of carcinogenesis.

Suppressor of cytokine signaling 2 (Socs2) deletion protects bone health of mice with DSS-induced inflammatory bowel disease

Individuals with inflammatory bowel disease (IBD) often present with poor bone health. The development of targeted therapies for this bone loss requires a fuller understanding of the underlying cellular mechanisms. Although bone loss in IBD is multifactorial, the altered sensitivity and secretion of growth hormone (GH) and insulin-like growth factor-1 (IGF-1) in IBD is understood to be a critical contributing mechanism. The expression of suppressor of cytokine signaling 2 (SOCS2), a well-established negative regulator of GH signaling, is stimulated by proinflammatory cytokines. Therefore, it is likely that SOCS2 expression represents a critical mediator through which proinflammatory cytokines inhibit GH/IGF-1 signaling and decrease bone quality in IBD. Using the dextran sodium sulfate (DSS) model of colitis, we reveal that endogenously elevated GH function in the Socs2^−/− mouse protects the skeleton from osteopenia. Micro-computed tomography assessment of DSS-treated wild-type (WT) mice revealed a worsened trabecular architecture compared to control mice. Specifically, DSS-treated WT mice had significantly decreased bone volume, trabecular thickness and trabecular number, and a resulting increase in trabecular separation. In comparison, the trabecular bone of Socs2-deficient mice was partially protected from the adverse effects of DSS. The reduction in a number of parameters, including bone volume, was less, and no changes were observed in trabecular thickness or separation. This protected phenotype was unlikely to be a consequence of improved mucosal health in the DSS-treated Socs2^−/− mice but rather a result of unregulated GH signaling directly on bone. These studies indicate that the absence of SOCS2 is protective against bone loss typical of IBD. This study also provides an improved understanding of the relative effects of GH/IGF-1 signaling on bone health in experimental colitis, information that is essential before these drugs are explored as bone protective agents in children and adults with IBD.

Summary: Using a mouse model of inflammatory bowel disease, this article provides an improved understanding of the relative effects of GH/IGF-1 on bone health in experimental colitis.

Gene-expression analysis of gleason grade 3 tumor glands embedded in low- and high-risk prostate cancer

The Gleason score (GS) of prostate cancer on diagnostic biopsies is an important parameter for therapeutic decision-making. Biopsy GS under-estimates the actual GS at radical prostatectomy in a significant number of patients due to sampling artifact. The aim of this study was to identify markers that are differentially expressed in Gleason grade 3 (GG3) tumor glands embedded in GS 4 + 3 = 7 and GS 3 + 3 = 6 prostate cancer using laser capture microdissection and RNA sequencing.

GG3 tumor glands embedded in nine GS 3 + 3 = 6 and nine GS 4 + 3 = 7 prostate cancers were isolated by laser capture microdissection of frozen radical prostatectomy specimens. After RNA amplification and RNA sequencing, differentially expressed genes in both GG3 components were identified by a 2log fold change > 1.0 and p-value < 0.05. We applied immunohistochemistry on a tissue micro-array representing 481 radical prostatectomy samples for further validation on protein level.

A total of 501 genes were up-regulated and 421 down-regulated in GG3 glands embedded in GS 4 + 3 = 7 as compared to GS 3 + 3 = 6 prostate cancer. We selected HELLS, ZIC2 and ZIC5 genes for further validation. ZIC5 mRNA was up-regulated 17 fold (p = 8.4E–07), ZIC2 8 fold (p = 1.3E–05) and HELLS 2 fold (p = 0.006) in GG3 glands derived from GS 4 + 3 = 7. HELLS expression of ≥ 1% occurred in 10% GS < 7, 17% GS 7 and 43% GS >7 prostate cancer (p < 0.001). Using a cut-off of ≥ 1%, protein expression of ZIC5 was present in 28% GS < 7, 43% GS 7 and 57% GS > 7 cancer (p < 0.001). ZIC2 was neither associated with GS nor outcome in our validation set. HELLS was independently predictive for biochemical-recurrence after radical prostatectomy (HR 2.3; CI 1.5–3.6; p < 0.01).

In conclusion, HELLS and ZIC5 might be promising candidate markers for selection of biopsy GS 6 prostate cancer being at risk for up-grading at prostatectomy.

Reprogramming human A375 amelanotic melanoma cells by catalase overexpression: Upregulation of antioxidant genes correlates with regression of melanoma malignancy and with malignant progression when downregulated

Reactive oxygen species (ROS) are implicated in tumor transformation. The antioxidant system (AOS) protects cells from ROS damage. However, it is also hijacked by cancers cells to proliferate within the tumor. Thus, identifying proteins altered by redox imbalance in cancer cells is an attractive prognostic and therapeutic tool. Gene expression microarrays in A375 melanoma cells with different ROS levels after overexpressing catalase were performed. Dissimilar phenotypes by differential compensation to hydrogen peroxide scavenging were generated. The melanotic A375-A7 (A7) upregulated TYRP1, CNTN1 and UCHL1 promoting melanogenesis. The metastatic A375-G10 (G10) downregulated MTSS1 and TIAM1, proteins absent in metastasis. Moreover, differential coexpression of AOS genes (EPHX2, GSTM3, MGST1, MSRA, TXNRD3, MGST3 and GSR) was found in A7 and G10. Their increase in A7 improved its AOS ability and therefore, oxidative stress response, resembling less aggressive tumor cells. Meanwhile, their decrease in G10 revealed a disruption in the AOS and therefore, enhanced its metastatic capacity.

These gene signatures, not only bring new insights into the physiopathology of melanoma, but also could be relevant in clinical prognostic to classify between non aggressive and metastatic melanomas.

A comprehensive repertoire of tRNA-derived fragments in prostate cancer

Prostate cancer (PCa) is the most common cancer among men in developed countries. Although its genetic background is thoroughly investigated, rather little is known about the role of small non-coding RNAs (sncRNA) in this disease. tRNA-derived fragments (tRFs) represent a new class of sncRNAs, which are present in a broad range of species and have been reported to play a role in several cellular processes. Here, we analyzed the expression of tRFs in fresh frozen patient samples derived from normal adjacent prostate and different stages of PCa by RNA-sequencing. We identified 598 unique tRFs, many of which are deregulated in cancer samples when compared to normal adjacent tissue. Most of the identified tRFs are derived from the 5’- and 3’-ends of mature cytosolic tRNAs, but we also found tRFs produced from other parts of tRNAs, including pre-tRNA trailers and leaders, as well as tRFs from mitochondrial tRNAs. The 5’-derived tRFs comprise the most abundant class of tRFs in general and represent the major class among upregulated tRFs. The 3’-derived tRFs types are dominant among downregulated tRFs in PCa. We validated the expression of three tRFs using qPCR. The ratio of tRFs derived from tRNA^LysCTT and tRNA^PheGAA emerged as a good indicator of progression-free survival and a candidate prognostic marker. This study provides a systematic catalogue of tRFs and their dysregulation in PCa and can serve as the basis for further research on the biomarker potential and functional roles of tRFs in this disease.

Contemporary Active Surveillance: Candidate Selection, Follow-up Tools, and Expected Outcomes

This article is a summary of the rationale for conservative management, the molecular biology of low-grade cancer, the principles of management, the expected outcome of surveillance, unanswered questions, and research opportunities.

CYP17A1-independent production of the neurosteroid-derived 5α-pregnan-3β,6α-diol-20-one in androgen-responsive prostate cancer cell lines under serum starvation and inhibition by Abiraterone

CYP17A1-independent intratumoral steroid hormone synthesis is regarded as one possible explanation for resistance to treatment with the CYP17-inhibitor Abiraterone (Abi). The aim of our study was therefore to investigate the steroid metabolism of prostate cancer cells under serum starvation and the effects of Abi treatment. We assessed steroid metabolism in a panel of prostate cancer cells under serum starvation by radioactivity detector-coupled HPLC and HPLC-ESI-ToF-mass spectrometry after treatment with pregnenolone, progesterone and allopregnanolone. We further evaluated the effects of Abi on steroid metabolism of testosterone, dihydrotestosterone (DHT) and dehydroepiandrosterone (DHEA) by enzyme immunoassays (EIAs). Androgen-responsive cell lines metabolized pregnenolone primarily to mitogenic steroid 5α-pregnan-3β,6α-diol-20-one under serum starvation. Co-administration of Abi lead to detectable concentrations of the Abi metabolite Δ⁴-Abi (D4A), known to inhibit enzymes other than CYP17A1 in steroid metabolism. In addition, co-administration of Abi abrogated pregnenolone metabolism and resulted in a CYP17A1-independent significant increase of DHEA (13- to >100-fold) and DHT (2.5-fold) in androgen-responsive cells. Our results demonstrate the CYP17A1-independent formation of 5α-pregnan-3β,6α-diol-20-one by androgen-responsive prostate cancer cells under serum starvation and its inhibition by Abi. Its metabolism from pregnenolone suggests a major steroidogenesis shift in these cells, hinting at a neuroendocrine transdifferentiation phenomenon. The marked increase of DHEA levels by Abi resembles the steroidogenic pathways in nervous tissue, in a manner that precludes CYP17A1 activity. To which extent these processes are responsible or involved in the development of resistance to Abi, needs to be further elucidated.

Androgen suppresses protein kinase D1 expression through fibroblast growth factor receptor substrate 2 in prostate cancer cells

In prostate cancer, androgen/androgen receptor (AR) and their downstream targets play key roles in all stages of disease progression. The protein kinase D (PKD) family, particularly PKD1, has been implicated in prostate cancer biology. Here, we examined the cross-regulation of PKD1 by androgen signaling in prostate cancer cells. Our data showed that the transcription of PKD1 was repressed by androgen in androgen-sensitive prostate cancer cells. Steroid depletion caused up regulation of PKD1 transcript and protein, an effect that was reversed by the AR agonist R1881 in a time- and concentration-dependent manner, thus identifying PKD1 as a novel androgen-repressed gene. Kinetic analysis indicated that the repression of PKD1 by androgen required the induction of a repressor protein. Furthermore, inhibition or knockdown of AR reversed AR agonist-induced PKD1 repression, indicating that AR was required for the suppression of PKD1 expression by androgen. Downstream of AR, we identified fibroblast growth factor receptor substrate 2 (FRS2) and its downstream MEK/ERK pathway as mediators of androgen-induced PKD1 repression. In summary, PKD1 was identified as a novel androgen-suppressed gene and could be downregulated by androgen through a novel AR/FRS2/MEK/ERK pathway. The upregulation of prosurvival PKD1 by anti-androgens may contribute to therapeutic resistance in prostate cancer treatment.

STK39, overexpressed in osteosarcoma, regulates osteosarcoma cell invasion and proliferation

Serine/threonine kinase 39 (STK39) is associated with hypertension, autism, Parkinson's disease and various types of cancer in recent years. This study investigated STK39 expression and possible roles in osteosarcoma using qPCR and western blot analysis. Compared to normal bone tissues, the mRNA and protein expression of STK39 was found to be upregulated in osteosarcoma. Using small interfering RNA transfection, STK39 was knocked down into two cell lines of osteosarcoma, U2OS and MG63, and the effects exerted on cell functioning were examined. The results showed that STK39 downregulation inhibited ostesarcoma cell proliferation and invasion. Moreover, STK39 knockdown in osteosarcoma cells significantly affected the expression of proteins connected to cell proliferation (proliferating cell nuclear antigen and p21) and invasion [Twist1, matrix metalloproteinase (MMP)2 and MMP9]. Phosphorylation of Smad2/3 was reduced by STK39 knock down. In conclusion, our data provide evidence that STK39 was overexpressed in osteosarcoma. STK39 may serve as an oncogene by adjusting the proliferation and invasion of osteosarcoma cells.

Role of GPR30 in estrogen-induced prostate epithelial apoptosis and benign prostatic hyperplasia

Several studies have implicated estrogen and the estrogen receptor (ER) in the pathogenesis of benign prostatic hyperplasia (BPH); however, the mechanism underlying this effect remains elusive. In the present study, we demonstrated that estrogen (17β-estradiol, or E2)-induced activation of the G protein-coupled receptor 30 (GPR30) triggered Ca²⁺ release from the endoplasmic reticulum, increased the mitochondrial Ca²⁺ concentration, and thus induced prostate epithelial cell (PEC) apoptosis. Both E2 and the GPR30-specific agonist G1 induced a transient intracellular Ca²⁺ release in PECs via the phospholipase C (PLC)-inositol 1, 4, 5-triphosphate (IP₃) pathway, and this was abolished by treatment with the GPR30 antagonist G15. The release of cytochrome c and activation of caspase-3 in response to GPR30 activation were observed. Data generated from the analysis of animal models and human clinical samples indicate that treatment with the GPR30 agonist relieves testosterone propionate (TP)-induced prostatic epithelial hyperplasia, and that the abundance of GPR30 is negatively associated with prostate volume. On the basis of these results, we propose a novel regulatory mechanism whereby estrogen induces the apoptosis of PECs via GPR30 activation. Inhibition of this activation is predicted to lead to abnormal PEC accumulation, and to thereby contribute to BPH pathogenesis.

The role of GATA2 in lethal prostate cancer aggressiveness

Advanced prostate cancer is a classic example of the intractability and consequent lethality that characterizes metastatic carcinomas. Novel treatments have improved the survival of men with prostate cancer; however, advanced prostate cancer invariably becomes resistant to these therapies and ultimately progresses to a lethal metastatic stage. Consequently, detailed knowledge of the molecular mechanisms that control prostate cancer cell survival and progression towards this lethal stage of disease will benefit the development of new therapeutics. The transcription factor endothelial transcription factor GATA-2 (GATA2) has been reported to have a key role in driving prostate cancer aggressiveness. In addition to being a pioneer transcription factor that increases androgen receptor (AR) binding and activity, GATA2 regulates a core subset of clinically relevant genes in an AR-independent manner. Functionally, GATA2 overexpression in prostate cancer increases cellular motility and invasiveness, proliferation, tumorigenicity, and resistance to standard therapies. Thus, GATA2 has a multifaceted function in prostate cancer aggressiveness and is a highly attractive target in the development of novel treatments against lethal prostate cancer.