The Role of P21 Protein Expression in Predicting Progression and Biological Behaviors of Gastric Adenocarcinomas

Background: P21 protein is a cyclin-dependent kinase inhibitor and has a crucial function as a cell cycle regulator in malignant tissues. Thus, its association with aggressive characteristics of malignant lesions is suggested. Objectives: We evaluated the expression level of P21 in gastric cancers and its association with the histopathological findings of cancer. Methods: This cross-sectional study was performed on gastric adenocarcinomas from radical gastrectomy. The histopathological examination was assessed by Hematoxylin Eosin. The immunohistochemistry technique was then used to assess the expression of the P21 marker. Results: P21 positivity was revealed in 28 specimens of the cancerous lesions with an overall prevalence of 70.0% in our population. There was no association between P21 positivity and tumor-related characteristics, including tumor location, type, grade and stage, as well as the size of the cancerous lesion. P21 positivity could not be related to perineural or lymphovascular invasion of the tumor (P-value 0.05). Conclusions: In our population, the expression of P21 may not be prognostic or predict tumor biological behavior among patients with gastric adenocarcinomas.