Figure 6.

Knockdown of insulin growth factor binding protein 3 (IGFBP3) promotes the activation of PI3K/AKT and RAS pathways in A549 and HepG2 cells. A, Western blot analysis confirmed that testis‐specific protein, Y‐linked 1 (TSPY1) reduced the endogenous IGFBP3 expression in A549 and HepG2 cells. B, Western blot analysis shows decreased IGFBP3 expression was correlated with the increased level of 3 key proteins (p‐AKT, p‐mTOR, and BCL2) of the PI3K/AKT signaling pathway in A549 and HepG2 cells. C, Western blot analysis showed higher levels of 4 key proteins (p‐RAF‐1, p‐MEK1/2, p‐ERK1/2, and JUN) of the RAS signaling pathway in A549 and HepG2 cells with IGFBP3 knockdown, relative to controls (shNC and siNC)