Proteomic analyses in advanced primary pterygium

ALGECIRAS M; BARROS MF; HM SERRA.; PIQUERAS CARMEN; SANJOY K. BHATTACHARYA; M FERNANDA SUAREZ; GONZALEZ MARIA EUGENIA; A. URRETS-ZAVALIA, J.

Congreso; ARVO Annual Meeting 2018; 2018

Pterygium is characterized as anabnormal wing-shaped growth of epithelial and fibrovascular tissue in thecorneoscleral limbus that centripetally invades the cornea. We performedproteomic studies comparing advanced pterygium versus normal conjunctivaspecimens. Conjunctivaltissues from affected and non affected areas of the conjunctiva were obtainedby the same surgeon from patients with pterygium in the advanced stage that didnot presented any other surface eye disease. Allprocedures were in accordance to the tenets of the Declaration of Helsinki. Specimenswere subjected to protein extraction followed by fractionation of proteins by?in solution? digestion, and proteomic mass spectrometry analysis were done usingan Orbitrap Q-Exactive mass spectrometer and results were analyzed using theThermo proteome discoverer 2.1 software using appropriate databases. Protein binding molecules were the most abundantglycoproteins found in pterygium (32.76 %), followed by molecules withcatalytic activities (17.60 %). Glycoproteins involved in regulation ofbiological process were richer than the ones involved in metabolic process(23.25% vs. 21.85%). Cellular glycoprotein components were mainly fromcytoplasm and cytosol (28.89%), whereas membrane components represented 23.63. Weobtained a protein profile from pterygium and normal conjunctive tissues.Comparative profiles between both kinds of specimens showed common glycoproteins(192); and unique glycoproteins in pterygium tissues and normal conjunctivalspecimens (473 vs. 272), respectively. Among the unique glycoproteins found inpterygium specimens we can mention many serum glycoproteins involved in immuneresponses, in coagulation cascade, and vitamin D-transporter; UV excisionrepair protein RAD23 homolog B; dehydrogenases; PAX3- and PAX7-binding protein1; proteasome subunits; HSP 90; protein S100-A10 and A11; mast cell carboxypeptidase;Rho-related GTP-binding protein, fibroblast growth factors; hepatitis B virusreceptor binding protein, pigment epithelium-derived factor;  and cytokeratins.The unique glycoproteins found in pterygium sustainthe concept that its genesis involves multifactorial mechanisms such as prolongedexposure to UVR, oxidative stress, angiogenesis, immune-mediated inflammatoryprocesses, abnormal behavior of limbal stem cells, imbalancebetween cell growth and apoptotic factors, as well as epithelial-mesenchymaltransition.