Tumorigenesis in retinoblastoma

Abstract

<P>THE MAJOR FACTOR RESPONSIBLE FOR TUMORIGENESIS IN RETINOBLASTOMAS IS INACTIVATION OF RB1 GENE. RECENT EVIDENCE HAS SUGGESTED THE INVOLVEMENT OF OTHER CANDIDATE GENES SUCH AS RB2, MGMT, TNFI? AND RBKIN IN ADDITION TO RB1. THEREFORE, WE INVESTIGATED MOLECULAR DEFECTS IN RETINOBLASTOMA TUMOURS IN THESE FIVE GENES BY LOH ANALYSIS, MUTATION SCREENING, PROMOTER HYPERMETHYLATION ANALYSIS AND GENE DOSAGE ANALYSIS. OUR RESULTS SUGGEST THAT THOUGH RB1 IS UNIVERSALLY INVOLVED IN RETINOBLASTOMA, SIGNIFICANT MOLECULAR DEFECTS ARE OBSERVED IN OTHER GENES AS WELL. THE FREQUENCY OF INVOLVEMENT OF OTHER GENES IN RETINOBLASTOMAS FROM LOCAL PATIENTS IS 52% IN RB2, 48% IN TNFI?, 40% IN RBKIN AND 25% IN MGMT. THIS STUDY WILL CONTRIBUTE TOWARDS BETTER UNDERSTANDING OF GENES INVOLVED IN TUMORIGENESIS OF RETINOBLASTOMA.</P>