Citrullination modulation maintains HIF-1A stabilization to drive tumor progression

HIF-1 (Hypoxia-inducible factor 1) is the master regulator responding to hypoxic conditions. Here, we found that HIF-1A is citrullinated by peptidyl arginine deiminase 4 (PADI4) at arginine 698, promoting HIF-1A stabilization and thus HIF-1-driven tumor growth. The knockdown of PADI4 could dramatically decrease HIF-1 protein expression without affecting the mRNA level, and this could be rescued by the proteasome inhibitor MG132 treatment under hypoxia. And PADI4-HIF-1A interaction is critical for HIF-1A stability and tumor progression, depending on the enzymatic activity of PADI4 and the pocket structure of PADI4. DHE, an FDA-approved agent for the treatment of migraine, was found serve as a potential antitumor agent throgh disrupting PADI4-HIF-1A interaction and suppressing HIF-1A stability. Taken together, we found the anti-tumor effect of DHE due to its effect on blocking PADI4-HIF-1A interaction and downregulating HIF-1A pathway in cancer cells. To figure out the influence of DHE on liver cancer cell under hypoxia, we treated Hep3B cell lines with two does DHE in 6 hours under Hypoxia and extracted mRNA for furthur RNA seq. To figure out the influence of DHE on liver cancer cell under hypoxia, we treated Hep3B cell lines with two does DHE in 6 hours under Hypoxia and extracted mRNA for furthur RNA seq.