Dear Editor:

In response to the article titled “Mechanisms and biomarker candidates in pterygium development”, published in your esteemed journal, which is a well thought out and written paper, I would like to raise few points regarding this study.

Pterygium may have among its causes factors such as: changes in cholesterol metabolism, inflammation, viral infection, oncogenic proteins, lymphangiogenesis, and epithelial-mesenchymal cell transition⁽¹⁾. We would like to add one more factor that may be related to the pathophysiology of pterygium.

Healthy conjunctival tissues may have Nod-like receptor pyrin3 (NLRP3). In pterygium, the NLRP3/caspase-1 pathway may be abnormally activated, accompanied by aberrant expression of IL-18 and IL-1β. There is a correlation between the number of fibroblasts and NLRP3. Activation of the NLRP3/caspase-1 pathway may be a cause of angiogenesis and fibroblast proliferation, which could induce pterygium recurrence. Nod-3 (NLRP3), caspase-1, IL-18 and IL-1β pyrodynamic receptors are common markers of pyroptosis, which is a form of programmed cell death that includes the release of inflammatory factors^(2-4).

Mitomycin C use in pterygium surgery reduces the recurrence rate, suppressing angiogenesis and fibroblast proliferation, inhibiting NLRP3/caspase-1 pathway activation and the expression of inflammatory factors such as TGF-β1, VEGF, and IL-6^(2-4).

REFERENCES

1. Wanzeler AC, Barbosa IA, Duarte B, Borges D, Barbosa EB, Kamiji D, et al. Mechanisms and biomarker candidates in pterygium development. Arq Bras Oftalmol. 2019;82(6):528-36.

2. Lamkanfi M, Dixit VM. Inflammasomes and their roles in health and disease. Annu Rev Cell Dev Biol. 2012;2:137-61.

3. Martinon F, Burns K, Tschopp J. The inflammasome: a molecular platform triggering activation of inflammatory caspases and processing of proIl-beta. Mol Cell. 2002;10(2):417-26.

4. Im H, Ammit AJ. The NLRP3 inflammasome: role in airway inflammation. Clin Exp Allergy. 2014;44(2):160-72.

Submitted for publication: December 10, 2019.
Accepted for publication: December 23, 2019.

Funding: This study received no specific financial support.

Disclosure of potential conflicts of interest: None of the authors have any potential conflicts of interest to disclose.