PAK1 and neoplasm: The level of Pak1 protein was significantly higher in tumor tissues (mean ± S.D. = 2.68 ± 1.26) and metastatic lymph nodes (2.77 ± 1.60) than the level in non-cancerous tissues, which was also set at 1.0 [21-23], (P < 0.0001, Figure.