A, B, Real-time PCR was performed to check the expression of JAK1 and IL6ST; C, Western blotting confirmed the activation of STAT3 pathways in resistant cell lines. Cell lysates were collected from randomly chosen sensitive and resistant cell lines (4 each), and Western blotting was performed to check the levels of JAK1, IL6ST, and pSTAT3 with specific antibodies. EGFR, BRAF, and KRAS mutation status of the cell lines are labeled at the bottom of Fig. 2C. (Grey square indicates mutation)