The ADP-ribose reactive NUDIX hydrolase isoforms can modulate HIF-1α in cancer cells

다국어 초록 (Multilingual Abstract)

<P><B>Abstract</B></P> <P>The human nucleoside-diphosphate linked moiety–X (NUDIX) hydrolases that utilize ADP-ribose and NADH/NAD<SUP>+</SUP> are overexpressed in cancer cells, but their roles in hypoxia inducible factor-1α (HIF-1α) regulation have not yet been revealed. Here, we showed that these NUDIX hydrolases negatively regulated HIF-1α accumulation by modulating the Ca<SUP>2+</SUP> dependent AMP-activated protein kinase (AMPK) signaling pathway. In specific, knockdown of NUDT9 resulted in accumulation of free ADP-ribose that triggered Ca<SUP>2+</SUP> influx mediated by transient receptor potential cation channel subfamily M member 2 and subsequent activation of Ca<SUP>2+</SUP>/calmodulin-dependent protein kinase kinase β (CaMKKβ). In addition, AMPK activation by CaMKKβ was shown to enhance HIF-1α accumulation. Our findings provide insights into the action of NUDIX hydrolases as an additional, discrete modulator of HIF-1α accumulation.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Knockdown of some ADP-ribose reactive NUDIX hydrolases enhances HIF-1α accumulation. </LI> <LI> Neither HIF-1 α mRNA expression nor protein degradation is affected by NUDT9 knockdown. </LI> <LI> Knockdown of NUDT9 enhances HIF-1α translation via TRPM2-CaMKKβ-AMPK pathway. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>