Positive expressions of HIF-1alpha and VEGF in stage T3-T4 tumors and those with vessel invasion, lymph node metastasis and distant metastasis were dramatically stronger than stage T1-T2 cases and those without vessel invasion, lymph node metastasis and distant metastasis.
The expression level of HIF-1alpha mRNA is surmised to have a significant correlation with tumor angiogenesis, cell proliferation, apoptosis, and metastasis.
Therefore, we hypothesized that the tumor environment in the lymph nodes may cause the reduction of CXCR4 levels in the metastatic tumor cells because of: (1) high SDF-1 levels and (2) lower levels of HIF-1alpha.
Multivariate analyses indicated that depth of tumour invasion, lymph node metastasis and positive surgical margin, but not HIF-1alpha, were independent prognostic factors.