Figure 6
From: Mahanine restores RASSF1A expression by down-regulating DNMT1 and DNMT3B in prostate cancer cells
Mahanine restores RASSF1A expression by degrading DNMTs via Akt. Prostate cancer cells express high levels of activated Akt, which phosphorylates and stabilizes DNMT1 and DNMT3B against proteasomal degradation. DNMTs enter the nucleus and methylate the promoter of RASSF1A gene to silence the expression of RASSF1A. Treatment of mahanine inhibits PDK1 and thereby prevents activation of Akt, which in turn compromises the stability of DNMTs, increases their ubiquitination and induces proteasomal degradation. In the absence of DNMT1 and DNMT3B, the RASSF1A promoter is demethylated and its expression is restored in prostate cancer cells. GF: Growth factor; RTK: Receptor tyrosine kinase; TFs: Transcription factors; P: Phosphorylated; M: Methylated; Ub: Ubiquitinated.