HistoneH3 demethylase JMJD2A promotes growth of liver cancer cells through up-regulating miR372

The emerging roles of lysine-specific demethylase 4A in cancer: Implications in tumorigenesis and therapeutic opportunities

Lysine-specific demethylase 4 A (KDM4A, also named JMJD2A, KIA0677, or JHDM3A) is a demethylase that can remove methyl groups from histones H3K9me2/3, H3K36me2/3, and H1.4K26me2/me3. Accumulating evidence suggests that KDM4A is not only involved in body homeostasis (such as cell proliferation, migration and differentiation, and tissue development) but also associated with multiple human diseases, especially cancers. Recently, an increasing number of studies have shown that pharmacological inhibition of KDM4A significantly attenuates tumor progression in vitro and in vivo in a range of solid tumors and acute myeloid leukemia. Although there are several reviews on the roles of the KDM4 subfamily in cancer development and therapy, all of them only briefly introduce the roles of KDM4A in cancer without systematically summarizing the specific mechanisms of KDM4A in various physiological and pathological processes, especially in tumorigenesis, which greatly limits advances in the understanding of the roles of KDM4A in a variety of cancers, discovering targeted selective KDM4A inhibitors, and exploring the adaptive profiles of KDM4A antagonists. Herein, we present the structure and functions of KDM4A, simply outline the functions of KDM4A in homeostasis and non-cancer diseases, summarize the role of KDM4A and its distinct target genes in the development of a variety of cancers, systematically classify KDM4A inhibitors, summarize the difficulties encountered in the research of KDM4A and the discovery of related drugs, and provide the corresponding solutions, which would contribute to understanding the recent research trends on KDM4A and advancing the progression of KDM4A as a drug target in cancer therapy.

Super-enhancers complexes zoom in transcription in cancer

Super-enhancers (SEs) consist of multiple typical enhancers enriched at high density with transcription factors, histone-modifying enzymes and cofactors. Oncogenic SEs promote tumorigenesis and malignancy by altering protein-coding gene expression and noncoding regulatory element function. Therefore, they play central roles in the treatment of cancer. Here, we review the structural characteristics, organization, identification, and functions of SEs and the underlying molecular mechanism by which SEs drive oncogenic transcription in tumor cells. We then summarize abnormal SE complexes, SE-driven coding genes, and noncoding RNAs involved in tumor development. In summary, we believe that SEs show great potential as biomarkers and therapeutic targets.

Design and synthesis of N-(1-(6-(substituted phenyl)-pyridazin-3-yl)-piperidine-3-yl)-amine derivatives as JMJD6 inhibitors

JMJD6 is a member of the JmjC domain-containing family and has been identified as a promising therapeutic target for treating estrogen-induced and triple-negative breast cancer. To develop novel anti-breast cancer agents, we synthesized a class of N-(1-(6-(substituted phenyl)-pyridazine-3-yl)-piperidine-3-yl)-amine derivatives as potential JMJD6 inhibitors. Among them, the anti-cancer compound A29 was an excellent JMJD6 binder (K_D = 0.75 ± 0.08 μM). It could upregulate the mRNA and protein levels of p53 and its downstream effectors p21 and PUMA by inhibiting JMJD6. Besides, A29 displayed potent anti-proliferative activities against tested breast cancer cells by the induction of cell apoptosis and cell cycle arrest. Significantly, A29 also promoted a remarkable reduction in tumor growth, with a TGI value of 66.6% (50 mg/kg, i.p.). Taken together, our findings suggest that A29 is a potent JMJD6 inhibitor bearing a new scaffold acting as a promising drug candidate for the treatment of breast cancer.

Mechanism of Phellodendron and Anemarrhena Drug Pair on the Treatment of Liver Cancer Based on Network Pharmacology and Bioinformatics

Background

This study aims to explore the key targets and signaling pathways of the traditional Chinese medicine Phellodendron and Anemarrhena drug pair (PADP) for the treatment of liver cancer.

Methods

Firstly, bioinformatics technology was used to analyze GSE62232 gene chip to obtain the differential genes of liver cancer. A network pharmacology technology was used to find the active components of PADP and their targets. Secondly, the differential genes were imported into STRING database to draw a PPI network, and network topology structure map combined with Cytoscape software. And the R language was used to identify differential gene targets and pathways through GO and KEGG pathway enrichment analysis. In addition, AutoDock Vina was used for molecular docking of core targets and core compounds. Moreover, GEPIA online analysis tool was used to perform survival analysis of the core target genes. Finally, RT-PCR was used to verify the changes of key target genes. CCK−8 assay was performed to detect cell proliferation. Flow cytometry was performed to detect the cell cycle and apoptotic. Transwell invasion assay was performed to detect cell invasion.

Results

Firstly, a total of 21,654 genes were obtained. After screening, 1019 differential genes were obtained, including 614 down-regulated genes and 405 up-regulated genes. Furthermore, after screening by ADME standards, 52 active ingredients were obtained, of which 37 were Phellodendron and 15 were Anemarrhena. And a total of 36 differential genes have been identified, including 13 up-regulated genes and 23 down-regulated genes. Moreover, through enrichment analysis, we found that PADP may treat liver cancer through multiple channels and multiple pathways including the p53 signaling pathway, IL-17 signaling pathway, TNF signaling pathway, Toll-like receptor signaling pathway and so on. Secondly, the molecular docking results showed that there was certain affinity between the core compounds and core target genes. In addition, GEPIA online analysis showed that ESR1, AR, CCNB1, CDK1, AKR1C3 and CCNA2 might become potential target genes for the survival and prognosis of PADP for the treatment of liver cancer. Finally, it was found that PADP could up regulate genes ESR1 and AR, down regulate genes CCNB1, CDK1, AKR1C3, and CCNA2. PADP could promote the apoptosis of liver cancer cells, shorten the cell cycle, and inhibit the proliferation and invasion of liver cancer cells.

Conclusion

PADP may treat liver cancer through multiple targets, multiple channels, and multiple pathways, thereby suppressing cancer cells and improving the living quality of patients.

Potential Biomarkers of miR-371-373 Gene Cluster in Tumorigenesis

microRNAs (miRNAs) are small non-coding RNA transcripts (20–24 nucleotides) that bind to their complementary sequences in the 3′-untranslated regions (3′-UTR) of targeted genes to negatively or positively regulate their expression. miRNAs affect the expression of genes in cells, thereby contributing to several important biological processes, including tumorigenesis. Identifying the miRNA cluster as a human embryonic stem cell (hESC)-specific miRNAs initially led to the identification of miR-371, miR-372, miR-373, and miR-373*, which can ultimately be translated into mature miRNAs. Recent evidence suggests that miR-371–373 genes are abnormally expressed in various cancers and act either as oncogenes or tumor suppressors, indicating they may be suitable as molecular biomarkers for cancer diagnosis and prevention. In this article, we summarize recent studies linking miR-371–373 functions to tumorigenesis and speculate on the potential applications of miR-371–373 as biomarkers for cancer diagnosis and treatment.

RFX5 promotes the progression of hepatocellular carcinoma through transcriptional activation of KDM4A

Regulatory factor X-5 (RFX5) represents a key transcription regulator of MHCII gene expression in the immune system. This study aims to explore the molecular mechanisms and biological significance of RFX5. Firstly, by analyzing ENCODE chromatin immunoprecipitation (ChIP)-seq in HepG2 and TCGA RNA-seq data, we discovered lysine-specific demethylase 4A (KDM4A), also named JMJD2A, to be a major downstream target gene of RFX5. Moreover, RFX5 was verified to bind directly to the KDM4A's promoter region and sequentially promoted its transcription determined by the ChIP-PCR assay and luciferase assay. In addition, RFX5-dependent regulation of KDM4A was demonstrated in HCC. Compared with adjacent non-tumor tissues, the expression levels of KDM4A were significantly raised in HCC tumor tissues. Notably, elevated levels of KDM4A were strongly correlated with HCC patient prognosis. Functionally, KDM4A overexpression largely rescued the growth inhibitory effects of RFX5 deletion, highlighting KDM4A as a downstream effector of RFX5. Mechanistically, the RFX5-KDM4A pathway promoted the progression of the cell cycle from G0/G1 to S phase and was protective against cell apoptosis through regulation of p53 and its downstream genes in HCC. In conclusion, RFX5 could promote HCC progression via transcriptionally activating KDM4A expression.

Targeting epigenetic regulators for cancer therapy: mechanisms and advances in clinical trials

Epigenetic alternations concern heritable yet reversible changes in histone or DNA modifications that regulate gene activity beyond the underlying sequence. Epigenetic dysregulation is often linked to human disease, notably cancer. With the development of various drugs targeting epigenetic regulators, epigenetic-targeted therapy has been applied in the treatment of hematological malignancies and has exhibited viable therapeutic potential for solid tumors in preclinical and clinical trials. In this review, we summarize the aberrant functions of enzymes in DNA methylation, histone acetylation and histone methylation during tumor progression and highlight the development of inhibitors of or drugs targeted at epigenetic enzymes.