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Despite the development of effective targeted therapies and a significant understanding of carcinogenesis and cancer progression, treatment resistance is a major obstacle in achieving durable long-term control in many types of cancers. Emerging evidence supports that nongenetic mechanisms could play an underappreciated role in therapy resistance. These mechanisms include phenotypic plasticity, which is recognized as a hallmark of cancer and translates to epigenetic and transcriptional control of gene expression. Alterations in the expression and activity of the epigenetic modifier enhancer of zeste homolog 2 (EZH2) support prostate cancer lineage plasticity and progression. EZH2 expression and activity is elevated in castration-resistant prostate cancer treated with androgen receptor pathway inhibitors and in treatment-resistant prostate cancer. Moreover, 17 known residues of EZH2 are phosphorylated on by multiple kinases that modulate its activity, localization, stability, and polycomb repressive complex (PRC2) assembly. In this review, we explore the contribution of EZH2 phosphorylation in regulating canonical PRC2 in a methylation-dependent manner as an epigenetic repressor and in a noncanonical manner independent of PRC2 as a transcription activator. Apart from the contribution of EZH2 phosphorylation at serine 21, threonine 350, and threonine 311 in prostate cancer progression and treatment resistance, we discuss how other EZH2 phosphorylated residues with unknown functions could contribute to prostate cancer based on their upstream regulators and potential therapeutic utility.

Treatment with androgen receptor pathway inhibitors (ARPIs) in prostate cancer leads to the emergence of resistant tumors characterized by lineage plasticity and differentiation toward neuroendocrine lineage. Here, we find that ARPIs induce a rapid epigenetic alteration mediated by large-scale chromatin remodeling to support activation of stem/neuronal transcriptional programs. We identify the proneuronal transcription factor ASCL1 motif to be enriched in hyper-accessible regions. ASCL1 acts as a driver of the lineage plastic, neuronal transcriptional program to support treatment resistance and neuroendocrine phenotype. Targeting ASCL1 switches the neuroendocrine lineage back to the luminal epithelial state. This effect is modulated by disruption of the polycomb repressive complex-2 through UHRF1/AMPK axis and change the chromatin architecture in favor of luminal phenotype. Our study provides insights into the epigenetic alterations induced by ARPIs, governed by ASCL1, provides a proof of principle of targeting ASCL1 to reverse neuroendocrine phenotype, support luminal conversion and re-addiction to ARPIs.

Background: The aim of this study was to evaluate the effect of ß-Dmannuronic acid (M2000) on related miRNAs to dendritic cells (DCs) differentiation. DC-based immunosuppressive drugs can suppress the progression of autoimmune diseases, however, their notable side effects in increasing the risk of infectious diseases and cancers should be considered. The β-D-mannuronic acid, as a novel non-steroidal anti-inflammatory agent, has been tested in various experimental models. Method: The effect of M2000 on expression of miRNA-155 and miRNA-221 was examined. To investigate how M2000 affects differentiation of human dendritic DCs in a defined inflammatory environment, human peripheral blood mononuclear cells were isolated from healthy blood and the monocytes were purified using anti-CD14 microbeads. The so isolated monocytes were subsequently incubated in the presence of M2000 in two different doses (3 and 6 mMol/well) adding granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 for inducing monocytes to immature DC and lipopolysaccharide for running DC differentiation. The expression of miRNA-155 and miRNA-221 were examined with Real Time PCR. Results: The results demonstrate that M2000 has no significant side effect on expression of miR-155 and miR-221 in both immature DC and mature DC process in vitro. Conclusion: Our findings show that β-D-mannuronic acid is a safe agent which has no adverse effect on regulatory miRNA-155 and miRNA-221 in dendritic cells.

β-d-Mannuronic acid (M2000) has shown its therapeutic effects with the greatest tolerability and efficacy in various experimental models such as experimental autoimmune encephalomyelitis (EAE), adjuvant induced arthritis (AIA), nephrotic syndrome, and acute glomerulonephritis. Despite pharmacological effects of β-D-mannuronic acid, there have been no systematic toxicological studies on its safety so far.The study was designed to determine the acute and subchronic toxicity of β-D-mannuronic acid, an anti-inflammatory agent, in healthy male NMRI mice and Wistar rats, respectively.For the acute toxicity study, the animals received orally five different single doses of β-D-mannuronic acid and were kept under observation for 14 d. In the subchronic study, 24 Wistar male rats were divided into four groups and were treated orally (gavage) once daily with test substance preparation at dose levels of 0, 50, 250, and 1250 mg/kg body weight for at least 63 consecutive days (9 weeks). Mortality, clinical signs, body weight changes, hematological and biochemical parameters, gross findings, organ weights, and histopathological determinations were monitored during the study.The results of acute toxicity indicated that the LD50 of β-D-mannuronic acid is 4.6 g/kg. We found no mortality and no abnormality in clinical signs, body weight, relative organ weights, or necropsy in any of the animals in the subchronic study. Additionally, the results showed no significant difference in hematological, biochemical, and histopathological parameters in rats.Our results suggest that β-D-mannuronic acid is relatively safe when administered orally in animals.

Experimental autoimmune encephalomyelitis (EAE) is an animal model of multiple sclerosis. EAE is mainly mediated by adaptive and innate immune responses that leads to an inflammatory demyelization and axonal damage. The aim of the present research was to examine the therapeutic efficacy of D-aspartic acid (D-Asp) on a mouse EAE model. EAE induction was performed in female C57BL/6 mice by myelin 40 oligodendrocyte glycoprotein (35-55) in a complete Freund's adjuvant emulsion, and D-Asp was used to test its efficiency in the reduction of EAE. During the course of study, clinical evaluation was assessed, and on Day 21, post-immunization blood samples were taken from the heart of mice for the evaluation of interleukin 6 and other chemical molecules. The mice were sacrificed, and their brain and cerebellum were removed for histological analysis. Our findings indicated that D-Asp had beneficial effects on EAE by attenuation in the severity and delay in the onset of the disease. Histological analysis showed that treatment with D-Asp can reduce inflammation. Moreover, in D-Asp-treated mice, the serum level of interleukin 6 was significantly lower than that in control animals, whereas the total antioxidant capacity was significantly higher. The data indicates that D-Asp possess neuroprotective property to prevent the onset of the multiple sclerosis.

The study’s background and aim: In this investigation, the safety property of M2000 (β-D-mannuronic acid) on differentiation, maturation and function of dendritic cells, was determined. β-D-mannuronic acid, as a novel immunosuppressive and anti-inflammatory agent, has been tested in various experimental models. In addition, DC-based immunosuppressive drugs can suppress the progression of autoimmune diseases, although, their notable side effects in increasing the risk of infectious diseases and cancers should be considered. Materials and Methods: The effect of M2000 on differentiation, maturation and function of dendritic cells was examined. To investigate how M2000 affects human dendritic cells (DC) in a defined inflammatory environment, human peripheral blood mononuclear cells (PBMC) were isolated from healthy blood and monocytes were purified using anti-CD14 microbeads. Monocytes were incubated with M2000 in two different doses (6 and 12 J.g/well) along with adding the granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 for inducing monocytes to immature DC and lipopolysaccharide for running DC maturation. The differentiation, maturation and function of dendritic cells were examined with flow cytometry and ELISA method. Result: The results demonstrate that M2000 has no significant side on differentiation, maturation and function of dendritic cells in immature DC and mature DC process in vitro. Conclusion: Our findings show that β-D-mannuronic acid (m2000) as a safe agent had no adverse effect on differentiation, maturation and function of dendritic cells which might be recommended as a novel immunosuppressive agent with no or fewer side effects in increasing the risk of infectious diseases and cancers.