High Expression Of P21 Activated Kinase 2(PAK2) In Esophageal Squamous Cancer And The Study Of Its Role

Background and purpose: P21 activated kinase 2(pak2),as a serine / threonine kinase,belongs to group I Pak together with pak1 and pak3.It can be involved in a variety of cellular biological activities,such as cell proliferation,motility and cell invasion.And it plays a promotive role in the onset and development of varieties of tumors.Recent researches have shown that high expression of PAK2 was found in gastric carcinoma,salivary gland adenoid cystic carcinoma and oral squamous cell carcinoma.It can promote the progression and motility of tumor cells,and it also have significance of the prognosis of tumors.However,there is no report about the PAK2 in esophageal cancer as yet.The purposes of this research are: 1.To investigate the protein and RNA expression of PAK2 in esophageal squamous cell cancer tissues and paired adjacent normal tissues and to analyze the relationship between the expression and clinicopathological factors and the prognosis.2.To study the effects of PAK2 on the biological behavior of esophageal squamous cell carcinoma cells.Methods: 1.Immunohistochemical method was used to test the expression of PAK2 in 62 cases of esophageal squamous cell cancers tissues and adjacent normal tissues.Analyzed the relationship between the expression of PAK2 and clinicopathological factors and the prognosis.2.q RT-pcr was used to test the RNA expression of PAK2 of 25 cases esophageal squamous cell cancer tissues and paired normal tissues.3.si RNA was used to reduced the expression of PAK2 in esophageal squamous cell lines TE-1 and KYSE-150,CCK-8 assay,wound healing assay and transwell invasion assay were used to test the changes in cell proliferation,motility and invasion respectively.Results: 1.The expression of pak2 in esophageal squamous cell carcinoma was significantly higher than that in adjacent normal tissues,and was significantly correlated with tumor invasion depth,lymph node metastasis and tumor staging.q RT-PCR analysis showed that the expression of pak2 RNA in esophageal squamous cell carcinoma was significantly higher than that in adjacent normal tissues.Survival analysis showed that the prognosis of patients with high expression of pak2 was significantly worse than that of patients with low expression.2.After the reduction of expression of PAK2 by si RNA,wound healing assay and transwell invasion assay showed that the motility and invasion ability were reduced,however,the proliferation of cells was not influenced according to the CCK-8 assay.Conclusions: In conclusion,the present research shows that the expression of PAK2 in esophageal squamous cell carcinoma is higher than normal tissue and has a significant correlation with depth and lymph node metastasis and TNM stage of tumor.It also has a relationship with the prognosis of tumor.PAK2 has a promotive role in cell motility and invasion but not in cell proliferation.Further study on the role of pak2 and its activation in cancer may provide a new perspective for the treatment of esophageal squamous cell carcinoma.