In lung adenocarcinoma cell line H1299 [24], Trop2 over-expression decreases ERK and AKT phosphorylation, Trop2 binds to IGF-1, inhibiting its ability to activate IGF-1R and reducing the activation of AKT and ERK by IGF-1R signaling pathway [25]. Here, TACSTD2 is linked to lung adenocarcinoma.