HIF1A and breast carcinoma: The expression of constitutively active or dominant negative form of HIF-1α in MDA-MB231 cells increases or decreases the metastasis and the blood vessel density in long bones; the HIF-1α knockdown by shRNA reduces the radiographic area of osteolytic lesions, decreases vessel density in bone metastasis, and increases survival time after the injection of breast cancer cells [40].