P21-activated kinase 1 and 4 were associated with colorectal cancer metastasis and infiltration.

BACKGROUND

P21-activated kinases (PAKs) are small guanosine triphosphate effectors that play critical roles in many fundamental cellular functions, including cytoskeletal reorganization and cell motility. PAKs are widely expressed in a variety of tissues and are often overexpressed in multiple cancer types. The aim of this study was to investigate the relationship between PAK1 and PAK4 and clinicopathologic features of colorectal cancer.

METHODS

PAK1 and PAK4 expression in colorectal cancer patients were investigated via TaqMan real-time polymerase chain reaction and immunohistochemistry and clinical analysis.

RESULTS

The relative expression levels of PAK1 and PAK4 gene in colorectal carcinoma tissues were significantly higher than those in normal tissues (P < 0.01). PAK4 expression was higher than PAK1 in the same cancer tissue. The expression of PAK1 and PAK4 increased gradually with the clinical stages in carcinoma tissues (P < 0.01). PAK1 expression was higher in lymph node positive patients, and PAK4 expression was higher in infiltration into serous layer patients (P < 0.05). PAK1 overexpression group has a higher recurrence/metastasis rate compared with that of the PAK1 low expression group. Follow-up analysis showed that the median progression-free survival time of the PAK1 high expression group was significantly shorter than that of the PAK1 low expression group.

CONCLUSIONS

PAK1 and PAK4 expression were associated with colorectal cancer metastasis and infiltration, PAK1 high expression may indicate poor prognosis of colorectal cancer.