GLI1 and neoplasm: Accumulating evidence suggests an essential role of hedgehog signaling in tumor cell proliferation [16], thus, we first assessed the levels of the key molecules of Gli1 and PTCH1 mRNA and found that knockdown of ROC1 expression was able to downregulate the expression of Gli1 and PTCH1, whereas ROC1 overexpression could upregulate the expression of Gli1 and PTCH1, compared with those of the corresponding controls (Fig. 2c, d).