MAPK1 and ocular melanoma: The expression levels of ERK2 were significantly higher in the shRNA‐OM group than the control‐OM group on days 3 and 7 (p < 0.05), and its expression was significantly higher in the shDRG2‐GM than the control‐GM on days 3 and 7 (p < 0.05) (Figure 4b).