Abstract
Abstract: :
Purpose: To investigate the differentially expressed genes in anterior polar cataracts (APC) characterized by transdifferentiated lens epithelial cells. Methods: We obtained human lens capsule specimens containing control lens epithelial cells (LECs) of nuclear cataract/normal lens (C), and transdifferentiated LECs of APC during surgery. The anterior polar plaque was isolated using fine forceps under a dissection microscope. Total cellular RNA was extracted and amplified. The amplified cDNA was subjected in subtractive hybridization. Each subtracted library was differentially screened and sequenced. The differentially expressed clones were confirmed by RT–PCR, Western blot analysis and immunofluoresence staining. Results: We identified novel up–regulated genes, tissue inhibitor of metalloproteinase–1 (TIMP–1) and tumour necrosis factor–a induced gene–6 (TNFIP–6 or TNF–a stimulating gene–6: TSG–6). We also found novel down–regulated genes in APC. The expression of TIMP–1 mRNA levels dramatically increased in APC and seldom increased in cortical type cataract that is common cataract type. The TSG–6 mRNA level was also increased in cortical type cataracts. By immunofluoresence staining, TIMP–1 protein was detected in the extracellular matrix and nucleus of LECs attached to APC capsules. Conclusion: We identified novel anterior polar cataract–related genes, TIMP–1 and TSG–6, which may have an important role in cataractogenesis.
Keywords: cataract • gene/expression • gene screening