MARK2 and osteosarcoma: In addition, the association of serine/threonine kinase (Ser/Thr kinase) with the PI3K-Akt pathway suggests that Solasonine may form an estrogen-kinase-PI3K regulatory axis in inhibiting the progression of osteosarcoma cells by inhibiting the phosphorylation modifications (for example, AKT1 Thr308/Ser473) and the downstream mRNA of AKT1 Thr308/Ser473 and downstream mTOR, thereby inhibiting tumor invasion, a mechanism confirmed in other tumor studies (36).