Multidrug resistance-associated proteins in glaucoma surgery.

Area of Science:

• Ophthalmology
• Molecular Biology
• Oncology

Background:

• Multidrug resistance (MDR) is a significant challenge in chemotherapy, particularly in glaucoma filtration surgery.
• Lung resistance protein (LRP) and multidrug resistance-related protein (MRP) are key proteins implicated in MDR.
• Understanding MDR mechanisms in ocular tissues is crucial for improving treatment outcomes.

Purpose of the Study:

• To investigate the presence and expression of LRP and MRP in Tenon tissue from glaucoma patients.
• To determine if these MDR-related proteins are expressed by conjunctival fibroblasts.

Main Methods:

• Immunohistochemistry was used to detect LRP and MRP in surgically removed Tenon specimens (n=15).
• Reverse-transcriptase polymerase chain reaction (RT-PCR) and fluorocytometry assessed expression in cultured Tenon fibroblasts.
• Cells were analyzed before and after treatment with mitomycin C or 5-fluorouracil.

Main Results:

• LRP expression was detected in 80% (8/10) of Tenon specimens.
• MRP expression was observed in 50% (5/10) of Tenon specimens.
• Cultured Tenon fibroblasts constitutively expressed both MRP and LRP at RNA and protein levels, unaffected by common chemotherapeutic agents.

Conclusions:

• Conjunctival fibroblasts express MDR-related proteins, including LRP and MRP, in addition to P-glycoprotein.
• The presence of these proteins suggests potential counteracting mechanisms against chemotherapeutic agents used in filtration surgery.
• Future strategies for chemotherapy in glaucoma surgery must consider these endogenous resistance mechanisms.