For both A549shNT and A549shHTATIP2 cells, the sorafenib IC50 values obtained under hypoxic condition were significantly greater than those obtained under normoxic conditions (n = 8; p < 0.01 for both cell lines) (Figure 1E), suggesting that hypoxia promotes tumor cell resistance to sorafenib treatment in vitro regardless of the presence or absence of HTATIP2 expression. Here, HTATIP2 is linked to neoplasm.