FIGURE 4.

Effects of VEGFR2 silencing combined with molecular targeted agents on oncogenic signaling pathways and cell growth. A‐C, Two different VEGFR2‐targeting siRNAs were used. The effects of VEGFR2 silencing on cell growth in PC‐9, H3122, and ABC‐20 cells. PC‐9 cells were treated with erlotinib (100 nmol/L) for 96 h, H3122 cells with alectinib (100 nmol/L) for 96 h, and ABC‐20 cells with crizotinib (1 μmol/L) for 96 h. All cell lines were treated with ramucirumab (150 μg/mL) for 96 h. *P < .005. D‐F, qRT‐PCR analysis showing efficient siRNA‐mediated VEGFR2 knockdown in different cell lines. GAPDH was used as the reference gene. Data are presented as means ± SE. G‐I, Phospho‐ERK1/2 (PC‐9 and ABC‐20 cells) and phospho‐AKT levels (H3122 cells) were lower in cells treated with the combination therapy compared with in cells treated with the molecular targeted agents alone. PC‐9, H3122, and ABC‐20 cells were treated with erlotinib (100 nmol/L), alectinib (100 nmol/L), and crizotinib (1 μmol/L), respectively. All cell lines were also exposed to ramucirumab (150 μg/mL); all treatments were performed for 96 h