Expression of Peroxiredoxin 2 and Vascular Endothelial Growth Factor Receptor 2 in Pterygium

The expression of peroxiredoxin 2 and vascular endothelial growth factor receptor 2 (VEGFR2) was detected in pterygium to investigate whether they are involved in the pathogenesis or recurrence of pterygium and to evaluate the association between peroxiredoxin 2 and VEGFR2 in pterygium.

Ten normal bulbar conjunctivae, 35 primary pterygia, and 35 recurrent pterygia were obtained. Formalin-fixed, paraffin-wax-embedded tissues were analyzed by immunohistochemistry with peroxiredoxin 2 and VEGFR2 antibodies.

There was no statistical difference between primary pterygia and recurrent pterygia in terms of age and sex (P = 0.685; P = 0.811). The expression rate of peroxiredoxin 2 (94.3%, 66/70) and VEGFR2 (61.4%, 43/70) was increased in pterygia compared with normal conjunctivae (negative). The expression of peroxiredoxin 2 in recurrent pterygia (negative 0, weak 0, moderate 27, strong 8) was higher than that in primary pterygia (negative 6, weak 16, moderate 13, strong 0) (P < 0.001). The expression of VEGFR2 in recurrent pterygia (negative 4, weak 5, moderate 12, strong 4) was higher than that in primary pterygia (negative 23, weak 10, moderate 1, strong 1) (P < 0.001). The expression of peroxiredoxin 2 was consistent with that of VEGFR2 in pterygium (r = 0.348, P = 0.006).

Overexpression of peroxiredoxin 2 and VEGFR2 in pterygium might be involved in the pathogenesis or recurrence of pterygium. The increase of VEGFR2 might be related to the increase of peroxiredoxin 2 in response to excessive reactive oxygen species from ultraviolet exposure.