Expression of p53 and Ki-67 proteins in patients with increasing severity and duration of pterygium

Abstract

Purpose: Pterygium is a triangular fibrovascular subepithelial ingrowth of degenerative bulbar conjunctival tissue over the cornea. It is now considered to be a result of uncontrolled cellular proliferation as overexpression of p53 protein and Ki-67 nuclear protein was found in the epithelium. This study was done to find the expression of p53 and Ki-67 with the severity and duration of the pterygium to explain the etiopathogenesis. Methods: Data were analyzed from 43 Indian participants of all age groups. All patients were divided according to the severity of pterygium (mild, moderate, and severe groups) and according to the duration of pterygium (4 years). The samples were studied by immunohistochemistry by using antibodies against p53 and Ki-67 proteins considering >5% expression as significant. Results: Of 43 cases, p53 and Ki-67 expression were positive in 33 cases. In mild, moderate, and severe cases p53 positivity was 33.3%, 78.4%, 100%, respectively. P53 expression increased with duration, 79.3% positive in 4 years. With increasing severity of pterygium, mild, moderate, and severe cases, Ki-67 positivity was 66.7%, 78.37%, 66.7%, respectively. Ki-67 expression with duration, 79.3% positive in 4 years of the duration of pterygium with no statistical significance. Conclusion: Our study revealed that with increasing duration and severity of pterygium, p53 expression was observed to be increasing. Ki-67 expression increased with the duration of pterygium but not with the severity.

Keywords

• immunohistochemistry
• ki-67
• p53
• paraffin embedding
• pterygium