Rabbit Anti-Human PAK1 (internal) Polyclonal antibody

Resectable pancreatic cancer has a high recurrence rate after curative surgery. Biomarkers are needed for distinguishing patients who may benefit from curative resection. In this study, we sought to analyze the prognostic value of p21-activated kinase 1 (PAK1), p21-activated kinase 4 (PAK4), human equilibrative nucleoside transporter 1 (hENT1), and thymidylate synthase (TS) in surgically resected pancreatic ductal adenocarcinomas. A total of 160 pancreatic cancer patients who underwent surgery with curative intent were retrospectively reviewed. Tissue microarrays were constructed and immunohistochemical stains were performed for PAK1, PAK4, hENT1, and TS. The absence of PAK4 expression in pancreatic adenocarcinomas was associated with poorer histologic differentiation (p < 0.001), shorter overall survival [hazard ratio (HR) = 2.86, 95% confidence interval (CI) 1.43-5.71; p = 0.003], and disease-free survival (HR = 2.29, 95% CI: 1.11-4.74; p = 0.025) on univariate analyses. In addition, more frequent venous invasion and lymph node metastases were seen in PAK4-negative tumors although not statistically significant. PAK1, hENT1, and TS expression status did not have significant influences on patient survival. In conclusion, PAK4 of the markers tested in this study may be a potential prognostic biomarker for pancreatic adenocarcinomas.

Gastric cancer (GC) is one of the most common malignancies worldwide. The prognosis of GC is unsatisfied owning to widespread metastasis. P21-activated kinase 1 (PAK1), a member of serine/threonine kinases, is associated with the progression of multiple types of human cancers. Here, we demonstrated that CDK4/6 inhibitor reduced GC cell viability and decreased PAK1 expression. Consistently, PAK1 ablation increased GC cell sensitivity exposed to CDK4/6 inhibitor and promoted DNA damage. We also revealed PAK1 depletion notably affected PDK1-AKT pathway, and PDK1 overexpression totally abrogated the effect of PAK1 deletion on DNA damage in GC cells. Additionally, PDK1 overexpression also rescued the increased GC cell sensitivity towards CDK4/6 inhibitor and the cell cycle arrest caused by PAK1 depletion. Our findings, therefore, suggested that PAK1 silencing increased sensitivity to CDK4/6 inhibition in gastric cancer cells via PDK1-AKT pathway. We, therefore, thought PAK1 as a promising therapeutic target for the treatment of CDK4/6 inhibitor-resistant gastric cancer.