Expression Of Cell Proliferation And Apoptosis Biomarkers In Pterygia And Normal Conjunctiva

Purpose: To analyze the expression of apoptosis and cell proliferation molecules inpterygium tissues of Chinese patients.Methods: Thirty-three pterygia were surgically removed using the bare scleraprocedure, and23normal bulbar conjunctivas were also obtained. Formalin-fixed,paraffin-wax-embedded tissues were analyzed by immunohistochemistry with anti-proliferating cell nuclear antigen (PCNA), Ki-67(a proliferating cell marker), mutantp53(mP53), Bcl-2associated X-protein (BAX), B-cell lymphoma gene2(Bcl-2), andcaspase-3antibodies. Terminal deoxynucleotidyl transferase-mediated dUTP-biotinnick end labeling assay (TUNEL) analysis was used to analyze the apoptotic cells.Results: Our study revealed that the positive rate of PCNA and Ki-67significantlyincreased in the pterygium samples compared to the normal conjunctiva samples. Inthe molecules involved in apoptosis, the results showed that the positive rate of Bcl-2and mP53significantly increased in the pterygium samples. However, no differencewas found between the pterygium and normal conjunctiva samples in the expressionof Bax and caspase-3. Through TUNEL analysis, apoptotic cells were seen in theentire width of the epithelial layer in normal conjunctivas but were found mainlyconfined to the outer layer of the epithelial cells in pterygia.Conclusions: The finding of high levels of cellular proliferation and low levels ofcellular apoptosis in pterygia confirmed that both cell apoptosis and proliferation are known to play an important role in human pterygium pathogenesis.