MAPK3 and osteosarcoma: MEK/ERK signaling is one of the typical MAPK signaling that plays vital roles in tumor cell proliferation, migration, and invasion, so we examined the effect of TRIM26 on MEK/ERK activation in osteosarcoma cells by examining the expression of MEK1/2, p-MEK1/2, ERK1/2, and p-ERK1/2 by western blotting.