In addition, PAK1 was overexpressed in GC.49, 50, 51 In the presence of the small GTPase protein Cdc42, PAK1 activation promotes MORC2 phosphorylation at the serine 677 site, which promotes cell cycle transition from the G1 to the S phase, thus inducing the growth and proliferation of GC cells.31 Here, CDC42 is linked to gastric cancer.