Conversely, siRNA-mediated knock-down of GNAQ in the uveal melanoma cell line, OMM1.3, which harbors the GNAQ-Q209L mutation, resulted in a decrease of phospho-ERK levels (Figure 3a)....Knockdown of GNAQ in OMM1.3 cells results in MAP-kinase inhibition, reduced growth and apoptosis...After 72 hours, GNAQ knockdown results in marked reduction of cell numbers, similar to the effect of MEK inhibitor U0126.