CopA3 treatment suppressed multidrug resistivity in HCT-116 cell line by p53-induced degradation of hypoxia-inducible factor 1α

Abstract

The major reason for multidrug resistance is the failure of chemotherapy in many tumors, including colon cancer. Hypoxia-inducible factor (HIF)-1α is a crucial transcription factor that simulates multiple cellular response to hypoxia. HIF-1α has been known to play a vital role towards tumor resistance; however, its mechanism of action is still not fully elucidated. N this study, we found that HIF-1α remarkably modulated drug resistance-associated proteins upon CopA3 peptide treatment against colon cancer cells. Abnormal rates of tumor growth along with high metastatic potential lacks the susceptibility towards cellular signals is a key characteristic in many tumor types. Moreover, in growing tumors, cells are exposed to insufficient nutrient supply and low oxygen availability. These stress force them to switch into adaptable and aggressive phenotypes. Our study investigated the interaction of HIF-1α and MDR gene association upon CopA3 treatment in the tumor microenvironment. We demonstrate that the multidrug resistance gene is associated with tumor resistance to chemotherapeutics, which upon CopA3 treatment promotes p53 activation and proteasomal degradation of HIF-1α, effecting the angiogenesis response to hypoxia. p53 downregulation augments HIF-1-dependent transcriptional activation of VEGF in response to oxygen deprivation.