HIF1A and central nervous system cancer: To examine whether the expression of IL6 correlates with autophagy and the level of hypoxia in human glioma, we performed immunohistochemical staining to detect the expression of IL6, STAT3 and p-STAT3 (the primary downstream signaling molecules of IL6), LC3B (a marker of autophagy) and HIF1A in 101 human glioma specimens with different grades and 3 normal brain tissues (Table 1).