VHL and non-small cell lung carcinoma: However, in this study, we found that over-expression of HPV-16 oncoproteins, especially E6, had no obvious effect on VHL protein expression, indicating that HPV-16 E6 oncoprotein inhibited HIF-1α degradation via VHL-independent pathways and the other underlying mechanisms possibly contribute to HIF-1α protein stability mediated by HPV-16 E6 oncoprotein in NSCLC cells.