Genotypic and phenotypic features of 39 Chinese patients with glycogen storage diseases type I, VI, and IX.

Glycogen storage diseases (GSDs) are abnormally inherited glycogen metabolism mainly affecting the liver, muscles, and heart. Deficiency of proteins involved in glycogen metabolism caused by genetic mutations are responsible for different subtype of GSDs. However, there are still some challenges in diagnosing GSD. This study includes 39 suspected GSDs patients from unrelated families in China. Next-generation sequencing (NGS) was used to investigate the reason for their diseases at the genetic level. Finally, all 39 patients were diagnosed with GSDs, including 20 GSD-Ia, 4 GSD-VI, and 15 GSD IX (12 GSD-IXa patients and 3 GSD-IXb patients). Thirty-two mutations in G6PC1, PYGL, PHKA2, and PHKB genes were identified, with 14 of them being novel variants. The pathogenicity of novel variants was classified according to ACMG guildlines and predicted by in slico algorithms. Mutations p.L216L and p.R83H in G6PC1 gene may be the hot spot mutation in Chinese. Hearing impairment is a rare clinical feature of GSD Ia, which has also been observed in our cohort. The severity of GSD VI and IX was indicated by our patients. Close follow-up should be applied to GSD VI and IX patients. Our findings provided evidence for building the phenotype-genotype of GSDs and expanded the mutation spectrum of related genes.

Myeloid differentiation factor-2/LY96, a potential predictive biomarker of metastasis and poor outcomes in prostate cancer: clinical implications as a potential therapeutic target.

Prostate cancer (CaP) is the most diagnosed cancer in males and the second leading cause of cancer deaths. Patients with localized tumors are generally curable. However, no curative treatment exists for patients with advanced and metastatic disease. Therefore, identifying critical proteins involved in the metastatic process would help to develop new therapeutic options for patients with advanced and aggressive CaP. We provide strong evidence that Myeloid differentiation factor-2 (MD2) plays a critical role in metastasis and CaP progression. Analysis of tumor genomic data showed that amplifications of MD2 and increased expression are associated with poor outcomes in patients. Immunohistochemistry analysis of tumor tissues showed a correlation between the expression of MD2 and cancer progression. The Decipher-genomic test validated the potential of MD2 in predicting metastasis. In vitro studies demonstrated that MD2 confers invasiveness by activating MAPK and NF-kB signaling pathways and inducing epithelial-mesenchymal transition. Furthermore, we show that metastatic cells release MD2 (sMD2). We measured serum-sMD2 in patients and found that the level is correlated to disease extent. We determined the significance of MD2 in metastasis in vivo and as a therapeutic target, showing that the molecular and pharmacological targeting of MD2 significantly inhibited metastasis in murine models. We conclude that MD2 predicts metastatic behavior, and serum-MD2 could be studied as a potential non-invasive biomarker for metastasis, whereas MD2 presence on prostate biopsy predicts adverse disease outcome. We suggest MD2-targeted therapies could be developed as potential treatments for aggressive metastatic disease.

[Clinical analysis of endoscopic esophageal dilation for the treatment of corrosive esophageal strictures in children]. / å† é•œä¸‹é£Ÿç®¡æ‰©å¼ æ²»ç–—å„¿ç«¥è èš€æ€§é£Ÿç®¡ç‹­çª„çš„ä¸´åºŠåˆ†æž.

OBJECTIVES: To investigate the clinical application of endoscopic esophageal dilation in the treatment of corrosive esophageal strictures in children. METHODS: A retrospective analysis was performed on the clinical data of 15 children with corrosive esophageal strictures who underwent endoscopic esophageal dilation in Children's Hospital, Zhejiang University School of Medicine. The clinical features, treatment modality of endoscopic esophageal dilation, number of dilations, complications, and prognosis were reviewed. RESULTS: A total of 96 esophageal dilations were performed in the 15 children with corrosive esophageal strictures, with a median of 6 dilations per child. Among them, 9 children (60%) underwent 6 or more dilations. The children with a stricture length of >3 cm had a significantly higher number of dilations than those with a stricture length of ≤3 cm (P<0.05). The children with strictures in a single segment had a significantly better treatment outcome than those with strictures in multiple segments (P=0.005). No complication was observed during all sessions of dilation. The overall effective rate (including significant improvement and improvement) of endoscopic esophageal dilation treatment was 87%, with 2 cases of failure. CONCLUSIONS: Endoscopic esophageal dilation is an effective and relatively safe treatment method for corrosive esophageal strictures in children, and children with strictures in a single segment tend to have a better treatment outcome than those with strictures in multiple segments.

Myeloid differentiation factor-2/LY96, a new predictive biomarker of metastasis in prostate cancer: Clinical implications as a potential therapeutic target.

Relapsed prostate cancer (CaP), usually treated with androgen deprivation therapy, acquires resistance to develop into lethal metastatic castration-resistant CaP. The cause of resistance remains elusive, and the lack of biomarkers predictive of castration-resistance emergence is a stumbling block in managing the disease. We provide strong evidence that Myeloid differentiation factor-2 (MD2) plays a critical role in metastasis and CaP progression. Analysis of tumor genomic data and IHC of tumors showed a high frequency of MD2 amplification and association with poor overall survival in patients. The Decipher-genomic test validated the potential of MD2 in predicting metastasis. In vitro studies demonstrated that MD2 confers invasiveness by activating MAPK and NF-kB signaling pathways. Furthermore, we show that metastatic cells release MD2 (sMD2). We measured serum-sMD2 in patients and found that the level is correlated to disease extent. We determined the significance of MD2 as a therapeutic target and found that targeting MD2 significantly inhibited metastasis in a murine model. We conclude that MD2 predicts metastatic behavior and serum-MD2 is a non-invasive biomarker for tumor burden, whereas MD2 presence on prostate biopsy predicts adverse disease outcome. We suggest MD2-targeted therapies could be developed as potential treatments for aggressive metastatic disease.

Chemokine receptor CXCR7 activates Aurora Kinase A and promotes neuroendocrine prostate cancer growth.

CXCR7 is an atypical chemokine receptor that recruits ß-arrestin (ARRB2) and internalizes into clathrin-coated intracellular vesicles where the complex acts as a scaffold for cytoplasmic kinase assembly and signal transduction. Here, we report that CXCR7 was elevated in the majority of prostate cancer (PCa) cases with neuroendocrine features (NEPC). CXCR7 markedly induced mitotic spindle and cell cycle gene expression. Mechanistically, we identified Aurora Kinase A (AURKA), a key regulator of mitosis, as a novel target that was bound and activated by the CXCR7-ARRB2 complex. CXCR7 interacted with proteins associated with microtubules and golgi, and, as such, the CXCR7-ARRB2-containing vesicles trafficked along the microtubules to the pericentrosomal golgi apparatus, where the complex interacted with AURKA. Accordingly, CXCR7 promoted PCa cell proliferation and tumor growth, which was mitigated by AURKA inhibition. In summary, our study reveals a critical role of CXCR7-ARRB2 in interacting and activating AURKA, which can be targeted by AURKA inhibitors to benefit a subset of patients with NEPC.

Ferroptosis: the vulnerability within a cancer monster.

Treatment-resistant cancer, such as neuroendocrine prostate cancer (NEPC), is a lethal disease with limited therapeutic options. RB1 is a tumor suppressor gene that is lost in a majority of NEPC tumors. In this issue of the JCI, Wang and colleagues examined how RB1 loss may sensitize cancer cells to ferroptosis inducers through elevation of ACSL4, a key enzyme that promotes lipid peroxidation and triggers ferroptosis. We discuss a high potential of RB1-deficient cells to undergo ferroptosis due to the elevation of ACSL4. This is normally kept in check by abundant expression of GPX4, an antioxidant enzyme, in cancer cells. This balance, however, is tilted by GPX4 inhibitors, leading to massive ferroptosis. We highlight possible therapeutic strategies that exploit this inherent vulnerability for targeting RB1-deficient, treatment-resistant cancer.

Palmitoyl acyltransferase ZDHHC7 inhibits androgen receptor and suppresses prostate cancer.

The hormonal transcription factor androgen receptor (AR) is a master regulator of prostate cancer (PCa). Protein palmitoylation, which attaches a palmitate fatty acid to a substrate protein, is mediated by a class of 23 ZDHHC (Zinc-Finger DHHC motif)-family palmitoyltransferases. Although palmitoylation has been shown to modify many proteins and regulate diverse cellular processes, little is known about ZDHHC genes in cancer. Here we examined ZDHHC family gene expression in human tissue panels and identified ZDHHC7 as a PCa-relevant member. RNA-seq analyses of PCa cells with ZDHHC7 de-regulation revealed global alterations in androgen response and cell cycle pathways. Mechanistically, ZDHHC7 inhibits AR gene transcription and therefore reduces AR protein levels and abolishes AR signaling in PCa cells. Accordingly, ZDHHC7 depletion increased the oncogenic properties of PCa cells, whereas restoring ZDHHC7 is sufficient to suppress PCa cell proliferation and invasion in vitro and mitigate xenograft tumor growth in vivo. Lastly, we demonstrated that ZDHHC7 is downregulated in human PCa compared to benign-adjacent tissues, and its loss is associated with worse clinical outcomes. In summary, our study reveals a global role of ZDHHC7 in inhibiting androgen response and suppressing PCa progression and identifies ZDHHC7 loss as a biomarker for aggressive PCa and a target for therapeutic intervention.

CXCR7 as a novel therapeutic target for advanced prostate cancer.

Chemokines and their cognate receptors comprise an intricate signaling network that becomes high-jacked by cancer cells for uncontrollable tumor growth and dissemination. ACKR3 (Atypical Chemokine Receptor 3), traditionally called CXCR7, is up-regulated in many cancers, including advanced prostate cancer, and represents promising targets for therapeutic intervention. Unlike typical G protein-coupled receptors such as CXCR4, CXCR7, once bound by its cognate ligand CXCL12, initiates the recruitment of ß-arrestin instead of G proteins, and results in rapid internalization and degradation of CXCL12, functioning as a scavenger receptor. However, recent evidence suggests that CXCR7 may be more than a scavenger or auxiliary receptor of CXCR4 and that it may play essential roles in regulating cancer progression, some of which are independent of CXCR4 and its ligands, such as CXCL12. Constitutively active CXCR7 binds to ß-arrestin. This protein complex internalizes to form a scaffold for assembling and activating various cytoplasmic kinases necessary for cell survival and tumor growth. Here we review and discuss the up-to-date knowledge on CXCR7 regulation and function and how this new understanding guides the development of CXCR7 inhibitors, focusing on prostate cancer.

The impact of exclusive enteral nutrition on the gut microbiome and bile acid metabolism in pediatric Crohn's disease.

BACKGROUND: Gut dysbiosis and associated bile acid (BA) metabolism play an important role in the pathogenesis of Crohn's disease (CD). We investigated the impacts of the exclusive enteral nutrition treatment (EEN) on the gut microbiome (GM) and BAs metabolism for patients with CD. METHODS: Targeted metabolomics analysis and metagenomics analysis were performed in feces to investigate the BA and GM changes of patients before and after 2-months EEN therapy. The Pediatric Crohn's Disease Activity Index (PCDAI) and fecal calprotectin were used to evaluate the severity and mucosal inflammation of CD. RESULTS: A total of 27 newly diagnosed pediatric patients with CD and 27 healthy controls were recruited in this study. Both GM structure and the secondary BA metabolism were significantly impaired in patients, which could return towards normal levels after EEN treatment. The most abundant taxa Firmicutes and 11 BAs were found closely associated with the PCDAI score and fecal calprotectin. Meanwhile, the close interactions between Firmicute bacteria and BAs might contribute to the remission of CD after EEN treatment. The qPCR data further confirmed that the relative expressions of Firmicutes phylum, and genus Flavonifractor and Clostridium V were improved after EEN treatment. CONCLUSIONS: Firmicutes bacteria and the balance of primary and secondary BA compositions in the gut were closely associated with the health status of CD disease indicated by the PCDAI score and fecal calprotectin. Understanding the recovery process of gut microbiome and BA metabolism will help us to explore the potential mechanisms of EEN therapy.

PALI1 promotes tumor growth through competitive recruitment of PRC2 to G9A-target chromatin for dual epigenetic silencing.

PALI1 is a newly identified accessory protein of the Polycomb repressive complex 2 (PRC2) that catalyzes H3K27 methylation. However, the roles of PALI1 in cancer are yet to be defined. Here, we report that PALI1 is upregulated in advanced prostate cancer (PCa) and competes with JARID2 for binding to the PRC2 core subunit SUZ12. PALI1 further interacts with the H3K9 methyltransferase G9A, bridging the formation of a unique G9A-PALI1-PRC2 super-complex that occupies a subset of G9A-target genes to mediate dual H3K9/K27 methylation and gene repression. Many of these genes are developmental regulators required for cell differentiation, and their loss in PCa predicts poor prognosis. Accordingly, PALI1 and G9A drive PCa cell proliferation and invasion in vitro and xenograft tumor growth in vivo. Collectively, our study shows that PALI1 harnesses two central epigenetic mechanisms to suppress cellular differentiation and promote tumorigenesis, which can be targeted by dual EZH2 and G9A inhibition.

Outcomes of Pediatric Patients with Crohn's Disease Received Infliximab or Exclusive Enteral Nutrition during Induction Remission.

Background: Both exclusive enteral nutrition (EEN) and infliximab (IFX) are recommended as induction therapy for pediatric Crohn's disease (CD). Our aim was to compare long-term disease outcomes of patients initially received with either IFX or EEN. Methods: Medical records of newly diagnosed, therapy naïve pediatric patients with CD received with IFX or EEN as induction therapy were retrospectively enrolled. Pediatric Crohn's disease activity index (PCDAI), Crohn's disease endoscopic index of severity (CDEIS), and other clinical data were compared pre- and postinduction therapy in two groups. The sustained remission rates and time coupled with body mass index (BMI) and height for age (HFA) changes were evaluated during more than 2-year long-term follow-up. Results: We collected data from 58 children with CD used IFX (23) or EEN (35) as induction remission therapy from January 2015 through June 2021 in our single-center. The median follow-up after starting IFX or EEN was 12.2 months (6.5-18.0months) and 18.9 months (7.1-30.7months), respectively. The proportion clinical and endoscopic remission in EEN (88.57% and 68.75%) was similar with that of IFX (73.91% and 80.77%) after induction therapy. No significant differences were also observed in BMI and HFA recovery between two groups. Among those who achieved clinical or endoscopic remission or endoscopic response, the sustained remission rates and time did not reveal any significant differences for those 10 patients who used 6-mercaptopurine/methotrexate (6-MP/MTX) or 14 patients who used IFX as maintenance treatment during longitudinal follow-up. Conclusions: Our study suggested that EEN treatment is similar with IFX therapy in short-term outcomes, and EEN+6-MP/MTX treatment is comparable with IFX+IFX therapy in long-term outcomes.

FOXA1 inhibits hypoxia programs through transcriptional repression of HIF1A.

Intratumoral hypoxia is associated with castration-resistant prostate cancer (CRPC), a lethal disease. FOXA1 is an epithelial transcription factor that is down-regulated in CRPC. We have previously reported that FOXA1 loss induces epithelial-mesenchymal transition (EMT) and cell motility through elevated TGFß signaling. However, whether FOXA1 directly regulates hypoxia pathways of CRPC tumors has not been previously studied. Here we report that FOXA1 down-regulation induces hypoxia transcriptional programs, and FOXA1 level is negatively correlated with hypoxia markers in clinical prostate cancer (PCa) samples. Mechanistically, FOXA1 directly binds to an intragenic enhancer of HIF1A to inhibit its expression, and HIF1A, in turn, is critical in mediating FOXA1 loss-induced hypoxia gene expression. Further, we identify CCL2, a chemokine ligand that modulates tumor microenvironment and promotes cancer progression, as a crucial target of the FOXA1-HIF1A axis. We found that FOXA1 loss leads to immunosuppressive macrophage infiltration and increased cell invasion, dependent on HIF1A expression. Critically, therapeutic targeting of HIF1A-CCL2 using pharmacological inhibitors abolishes FOXA1 loss-induced macrophage infiltration and PCa cell invasion. In summary, our study reveals an essential role of FOXA1 in controlling the hypoxic tumor microenvironment and establishes the HIF1A-CCL2 axis as one mechanism of FOXA1 loss-induced CRPC progression.

Diagnosis, treatment, and prevention of severe acute hepatitis of unknown etiology in children.

BACKGROUND: Severe acute hepatitis of unknown etiology in children has recently exhibited a global trend of concentrated occurrence. This review aimed to summarize the current available information regarding the outbreak of severe acute hepatitis and introduce our hospital's previous experiences with the diagnosis and treatment of severe acute hepatitis for reference. DATA SOURCES: Websites including the UK Health Security Agency, European Centre for Disease Prevention and Control, CDC, WHO, and databases including PubMed/Medline, Cochrane Library, Embase and Web of Science were searched for articles on severe acute hepatitis in children. RESULTS: As of May 26, 2022, a total of 650 cases have been reported in 33 countries; at least 38 (6%) children required liver transplantation, and nine (1%) died. Cases are predominantly aged between 3 and 5 years old, and there are no epidemiological links among them. The common manifestations are jaundice, vomiting and pale stools. Adenovirus tested positive in most cases, and SARS-CoV-2 and other viruses were detected in a few cases, but virus particles were not found in liver tissue. Adenovirus immunohistochemistry showed immunoreactivity in the intrasinusoidal lumen from some liver samples. The hierarchical treatment includes symptomatic and supportive therapy, management of coagulation disorders and hepatic encephalopathy, artificial liver support, and liver transplantation (approximately 6%-10% of cases require liver transplant). CONCLUSIONS: The etiology of this severe acute hepatitis in children is not clear. The clinical features are severe acute hepatitis with significantly elevated liver enzymes. Clinicians need to be alert to children with hepatitis.

[Effectiveness of induction therapy with exclusive enteral nutrition in pediatric Crohn's disease]. / å ¨è‚ å† è¥å »å¯¹å„¿ç«¥å ‹ç½—æ©ç— è¯±å¯¼ç¼“è§£ç–—æ•ˆç ”ç©¶.

OBJECTIVES: To evaluate the effectiveness of induction therapy with exclusive enteral nutrition (EEN) in pediatric Crohn's disease (CD). METHODS: A retrospective analysis was performed on the medical data of 62 children with CD who received EEN in Children's Hospital, Zhejiang University School of Medicine, from March 2013 to August 2021. The medical data included general information and height, weight, Pediatric Crohn's Disease Activity Index (PCDAI), Crohn's Disease Endoscopic Index of Severity, C-reactive protein, erythrocyte sedimentation rate, and serum albumin level before treatment and after 8 weeks of treatment. The changes in the above indicators were compared before and after treatment. RESULTS: Among the 62 children with CD, there were 39 boys (63%) and 23 girls (37%), with a mean age of (11.9±3.0) years at diagnosis. Among the 55 children who completed EEN treatment for at least 8 weeks, 48 (87%) achieved clinical remission at week 8. PCDAI at week 8 was significantly lower than that before treatment (P<0.001). Except for 17 children with involvement of the small intestine alone and 3 children with involvement of the colon who did not receive colonoscopy reexamination, the remaining 35 children with involvement of the colon received colonoscopy reexamination after the 8-week EEN treatment. Of the 35 children, 29 (83%) achieved mucosal healing. As for the 48 children who achieved clinical remission at week 8, there were significant improvements in height-for-age Z-score and body mass index-for-age Z-score at week 8 (P<0.01). As for the 7 children who did not achieve clinical remission at week 8, there were no significant changes in height-for-age Z-score and body mass index-for-age Z-score at week 8 (P>0.05). CONCLUSIONS: The 8-week EEN treatment has a good effect on clinical remission and mucosal healing in children with CD. For the children with CD achieving clinical remission, EEN can improve their height and body mass index.

The role of NSD1, NSD2, and NSD3 histone methyltransferases in solid tumors.

NSD1, NSD2, and NSD3 constitute the nuclear receptor-binding SET Domain (NSD) family of histone 3 lysine 36 (H3K36) methyltransferases. These structurally similar enzymes mono- and di-methylate H3K36, which contribute to the maintenance of chromatin integrity and regulate the expression of genes that control cell division, apoptosis, DNA repair, and epithelial-mesenchymal transition (EMT). Aberrant expression or mutation of members of the NSD family is associated with developmental defects and the occurrence of some types of cancer. In this review, we discuss the effect of alterations in NSDs on cancer patient's prognosis and response to treatment. We summarize the current understanding of the biological functions of NSD proteins, focusing on their activities and the role in the formation and progression in solid tumors biology, as well as how it depends on tumor etiologies. This review also discusses ongoing efforts to develop NSD inhibitors as a promising new class of cancer therapeutic agents.

HOXB13 suppresses de novo lipogenesis through HDAC3-mediated epigenetic reprogramming in prostate cancer.

HOXB13, a homeodomain transcription factor, critically regulates androgen receptor (AR) activities and androgen-dependent prostate cancer (PCa) growth. However, its functions in AR-independent contexts remain elusive. Here we report HOXB13 interaction with histone deacetylase HDAC3, which is disrupted by the HOXB13 G84E mutation that has been associated with early-onset PCa. Independently of AR, HOXB13 recruits HDAC3 to lipogenic enhancers to catalyze histone deacetylation and suppress lipogenic regulators such as fatty acid synthase. Analysis of human tissues reveals that the HOXB13 gene is hypermethylated and downregulated in approximately 30% of metastatic castration-resistant PCa. HOXB13 loss or G84E mutation leads to lipid accumulation in PCa cells, thereby promoting cell motility and xenograft tumor metastasis, which is mitigated by pharmaceutical inhibition of fatty acid synthase. In summary, we present evidence that HOXB13 recruits HDAC3 to suppress de novo lipogenesis and inhibit tumor metastasis and that lipogenic pathway inhibitors may be useful to treat HOXB13-low PCa.

A Genome-Wide CRISPR Activation Screen Identifies PRRX2 as a Regulator of Enzalutamide Resistance in Prostate Cancer.

Androgen receptor (AR) pathway inhibitors are the mainstay treatment for advanced prostate cancer, but resistance to therapy is common. Here, we used a CRISPR activation screen in metastatic castration-sensitive prostate cancer cells to identify genes that promote resistance to AR inhibitors. Activation of the TGFß target gene paired-related homeobox2 (PRRX2) promoted enzalutamide resistance. PRRX2 expression was the highest in double-negative prostate cancer (DNPC), which lack AR signaling and neuroendocrine differentiation, and a PRRX2-related gene signature identified a subset of patients with DNPC with reduced overall survival. PRRX2-expressing cells showed alterations in the CDK4/6/Rb/E2F and BCL2 pathways. Accordingly, treatment with CDK4/6 and BCL2 inhibitors sensitized PRRX2-expressing, castration-resistant tumors to enzalutamide. Overall, PRRX2 was identified as a driver of enzalutamide resistance. The PRRX2 signature merits investigation as a biomarker of enzalutamide resistance in prostate cancer that could be reversed with CDK4/6 and BCL2 inhibitors. SIGNIFICANCE: PRRX2 mediates enzalutamide resistance via activation of the E2F and BCL2 pathways, which can be targeted with CDK4/6 and BCL2 inhibitors to reverse resistance.

Case Report: Identification of a Novel Homozygous Mutation in GPD1 Gene of a Chinese Child With Transient Infantile Hypertriglyceridemia.

Transient infantile hypertriglyceridemia is a rare autosomal recessive disorder characterized by hypertriglyceridemia, hypohepatia, hepatomegaly, hepatic steatosis and fibrosis in infancy. Mutations in GPD1 gene are considered the causative factor but the underlying mechanism of this disorder is still enigmatic. To date, only 24 different GPD1 mutations have been reported in the literature worldwide with transient infantile hypertriglyceridemia or relevant conditions. Here we report a Chinese girl who developed hepatomegaly hepatic steatosis, elevated transaminase and hypertriglyceridemia from the age of 4 months. A novel homozygous variant c.454C>T (p.Q152*) was found in GPD1 gene by next-generation sequencing. This patient is the 3rd Asian reported with transient infantile hypertriglyceridemia. We summarized the clinical presentations of transient infantile hypertriglyceridemia and also expanded the spectrum of disease-causing mutations in GPD1.

Going beyond Polycomb: EZH2 functions in prostate cancer.

The Polycomb group (PcG) protein Enhancer of Zeste Homolog 2 (EZH2) is one of the three core subunits of the Polycomb Repressive Complex 2 (PRC2). It harbors histone methyltransferase activity (MTase) that specifically catalyze histone 3 lysine 27 (H3K27) methylation on target gene promoters. As such, PRC2 are epigenetic silencers that play important roles in cellular identity and embryonic stem cell maintenance. In the past two decades, mounting evidence supports EZH2 mutations and/or over-expression in a wide array of hematological cancers and solid tumors, including prostate cancer. Further, EZH2 is among the most upregulated genes in neuroendocrine prostate cancers, which become abundant due to the clinical use of high-affinity androgen receptor pathway inhibitors. While numerous studies have reported epigenetic functions of EZH2 that inhibit tumor suppressor genes and promote tumorigenesis, discordance between EZH2 and H3K27 methylation has been reported. Further, enzymatic EZH2 inhibitors have shown limited efficacy in prostate cancer, warranting a more comprehensive understanding of EZH2 functions. Here we first review how canonical functions of EZH2 as a histone MTase are regulated and describe the various mechanisms of PRC2 recruitment to the chromatin. We further outline non-histone substrates of EZH2 and discuss post-translational modifications to EZH2 itself that may affect substrate preference. Lastly, we summarize non-canonical functions of EZH2, beyond its MTase activity and/or PRC2, as a transcriptional cofactor and discuss prospects of its therapeutic targeting in prostate cancer.