Poor prognosis and advanced clinicopathological features of clear cell renal cell carcinoma (ccRCC) are associated with cytoplasmic subcellular localisation of Hypoxia inducible factor-2α.

Journal Article (Journal Article)

BACKGROUND: Pre-clinical studies have implicated hypoxia inducible factor (HIF)-2α as an important oncogene for clear cell renal cell carcinoma (ccRCC). Generally considered to act as a nuclear transcription factor, a recent study has also implicated HIF-2α as a protein translational initiation complex function within the cytoplasm (Uniacke et al., 2012). We hypothesised that both the absolute expression as well as the sub-cellular localisation of HIF-2α would predict clinicopathological features and cancer specific survival (CSS) in ccRCC. METHODS: A tissue microarray (TMA) study was conducted on three hundred and eight ccRCC patients. Survival differences were investigated with the log rank test and associations with CSS with uni- and multivariate Cox regression analyses. Recursive partition tree analysis was used to identify relevant cutoff values. RESULTS: High HIF-2α nuclear (N) (cutoff >32%) expression was associated with smaller tumour sizes (p=0.002) and lower Fuhrman grades (p=0.044), whereas tumours with high cytoplasmic (C) HIF-2α (>0%) more often had positive lymph nodes (p=0.004), distant metastases (p=0.021) and higher Fuhrman grades (p<0.0001). After adjustment for TNM stage, Eastern Cooperative Oncology Group performance status (ECOG PS), and Fuhrman grade, both continuous (p<0.0001) and dichotomised (p<0.0001) HIF-2α C variables remained significant predictors of CSS, while neither HIF-2α N variable was retained. CONCLUSION: Our investigation supports that HIF-2α may have a unique tumour promoter role in the cytoplasm. This preliminary finding justifies further experimental and mechanistic studies that examine the biological functions of HIF-2α when located in the cytoplasm.

Full Text

Duke Authors

Cited Authors

  • Kroeger, N; Seligson, DB; Signoretti, S; Yu, H; Magyar, CE; Huang, J; Belldegrun, AS; Pantuck, AJ

Published Date

  • May 2014

Published In

Volume / Issue

  • 50 / 8

Start / End Page

  • 1531 - 1540

PubMed ID

  • 24565854

Electronic International Standard Serial Number (EISSN)

  • 1879-0852

Digital Object Identifier (DOI)

  • 10.1016/j.ejca.2014.01.031

Language

  • eng

Conference Location

  • England