Modulation of H3K4 trimethylation by KDM5A and MLLs impacts metabolic adaptability in prostate and cervical cancer cells

Abstract

Chemical modifications of chromatin modulate gene expression and induce essential metabolic plasticity for tumor growth. Accumulation of H3K4me3 in the promoter of a gene activates transcription by making the promoter accessible to the polymerases. Methylation of H3K4 is catalysed by MLLs and demethylation of H3K4me3 is catalysed by KDM5 family proteins. Herein, we investigated if genes encoding the enzymes involved in glucose metabolism are dependent on KDM5A and MLL1, and if targeting the H3K4me3 would help in modulating the resilience of cancer cells. We present that KDM5A modulates most of the metabolic genes in a demethylase dependent manner as assesses by H3K4me3 occupancy on G6PD and catalase promoters. Targeting its expression would indeed help in sensitizing cancer cells to ROS dependent apoptotic cell death. We elucidated the differences in the epigenetic regulation in cancerous cells originated from cervical and prostate tissues and used a normal skin keratinocyte for comparison. In cervical and prostate cancers - KDM5A activated glycolysis but downregulates other metabolic processes. In cervical cancer, which majorly depends on PPP, changes in KDM5A did not modulate the G6PD expression. Further, we have shown that curcumin treatment enhanced KDM5A expression and downregulated MLL2 in cancer cell lines but not in keratinocyte cells. Curcumin inhibited metabolic pathways and enhanced apoptosis in cancer cells without affecting keratinocyte cells by modulating KDM5A and MLL levels. This work also strengthens the basic concept that, epigenetic modulations of genes in a tissue precisely depends on signal and sites of modification(s).