Expression of HIF-1α and Glut-1 in human bladder cancer

HIF-1 is a heterodimer consisting of the HIF-1α and HIF-1β subunits, and HIF-1α is the unique oxygen regulated subunit that determines HIF-1 activity. HIF-1α upgrades many gene products which include the glucose transporter protein 1 (Glut-1). Immunohistochemical studies using a monoclonal antibody specific for HIF-1α indicate that the overexpression of HIF-1α occurs in the most common forms of human cancer, including bladder cancer. The expression of Glut-1 in human bladder cancer is associated with poor prognosis and a low survival rate. To our knowledge this is the first study to compare the expression of both HIF-1α and Glut-1 with clinico-pathological characteristics in superficial and invasive human bladder cancer (all invasive bladder cancer patients received radical radiotherapy). The Kaplan-Meier survival analysis curve shows a significant association of HIF-1α expression with recurrence and survival in superficial bladder cancer and shows a significant association of Glut-1 with survival in invasive bladder cancer [chi² (4)=10.52; Pr > chi²=0.0012].