Clinical Significance Of Expression Of HIF-1α And P-gp As Prognostic Markers In Colorectal Carcinoma

Background and Objective: Over-expression of Hypoxia-inducible factor-1αin tumors was known to be associated with resistance to radiation,chemotherapy and with the more malignant tumor phenotypes relative to increased invasiveness,metastatic potentia1.Furthermore,research has shown that HIF-1αover-expression is associated with multidrug protein (p-gp) in human tumors. So we investigate HIF-1αand P-gp protein expression and prognosis of patients with colorectal carcinoma.Methods: The immunohistochemical expression of HIF-1αand P-gp was evaluated in 30 formalin-fixed, paraffin-embedded postoperative colorectal carcinoma tissue samples. Correlations with clinicopathologic characteristics were determined by cross- tabulations,and the impact of HIF-1αand P-gp protein expression on survival endpoints was determined by univariate and multivariate analysis.Results: The positive percentage of HIF-1αprotein was (56.7% ),The positive rate of P-gp protein was(80% ) in colorectal carcinoma tissue samples,Spearman rank correlation test showed a positive corelation between HIF-1αand P-gp(P<0.05);the protein expression of HIF-1αand P-gp were vice-related to differentiation;and the protein expression of HIF-1αhad positive correlations with lymph node metastasis,and had vice correlation with disease free survival and overall survival(P<0.05). There were no relationship between the two proteins mentioned as above and location,gross type,distance metastasis and stage of colorectal carcinoma(P>0.05).Conclusions: HIF-1αand P-gp might represent independent biologic marker evaluating the prognosis of patients with colorectal carcinoma.HIF- 1αmay play an important role in multidrug resistance,which may provide a novel application strategy gene targeted therapy of colorectal carcinoma.