Tear film levels of interleukin- (IL-) 6, IL-8, and vascular endothelial growth factor (VEGF) were investigated over time, and preoperative concentrations were linked to corneal neovascularization and pterygium size.
Abnormal p53 expression in the epithelium of primary and recurrent pterygium specimens suggests that pterygium is a growth disorder rather than a degeneration.
Fluorescence telomeric repeat amplification protocol was used to measure telomerase activity in whole pterygium samples from 9 cases and in the epithelium and stroma of pterygium from another 10 cases. p53 protein content was measured by enzyme-linked immunosorbent assay (ELISA) in tissues obtained from 7 eyes, as well as in epithelial cell suspensions collected by brush cytology in 8 eyes.
Loss of heterozygosity (LOH), increased P53 expression and the presence of oncogenic viruses, such as human papilloma virus (HPV) and herpes simplex virus (HSV), have been detected in pterygia, supporting the possible neoplastic nature of the lesion.
Since mutated p53 is one of the most frequent gene abnormalities in human cancer, we hypothesized that mutation of p53 may play an important role in growth and recurrence of pterygia, a dysplasia of the conjunctiva.
The use of single intra lesional injection of Avastin in pterygium decreased vascularity and decreased VEGF expression in injected pterygium after one month.
We have analyzed the status and expression of the p53 gene in epithelial cells derived from pterygium and have demonstrated that the p53 gene has undergone a monoallelic deletion.
We examined specimens--1 of pinguecula, 13 of pterygia (7 primary, 1 recurrent, 1 with dysplasia, and 4 primary not tested for p53), and 10 of limbal tumors (2 with actinic keratosis dysplasia, 1 with conjunctival intraepithelial neoplasia, 3 with carcinoma in situ, and 4 with squamous cell carcinoma)-expressing p53.
After p53 protein was found to be abnormally expressed in the epithelium, researchers suggested that a pterygium may be a tumor, but additional evidence is required to support this hypothesis.
There was a significant relationship between VEGF-C mRNA and LVA, LMD, and LVL, while VEGF-A mRNA was only closely correlated with LMD in recurrent pterygia.
We studied, with immunohistochemistry, the presence and localization of thymine dimers in the epithelial and stromal components of the human primary pterygium and its recurrences with a special emphasis on the vascular network and its interactions with the p53 tumor suppressor gene protein.
In addition, we found a significant relationship between VEGF-C mRNA expression and LMVD in grades 1, 2, and 3 pterygia, whereas VEGF-A mRNA expression correlated closely with LMVD only in grade 1 pterygia.
The high expression levels of tumor protein p53 (TP53) observed in laboratory studies of pterygium seem to contradict the fast-growing nature of its clinical behavior, and TP53 mutations have been suggested.