Molecular Cytogenetic Characterization Of Cell Lines Lacking Expression Of Interferon Regulatory Factor-1 on Chromosome 5

Abstract

The molecular cytogenetic techniques of fluorescence in situ hybridization (FISH) and karyotyping by means of GTG-banding were used to determine if a chromosomal abnormality could be detected in cell lines lacking expression of the Interferon Regulatory Factor -1 gene (IRF-1). It is believed that IRF-1 plays an important role in the biological immune response leading to the presence of Human Leukocyte Antigens (HLA) class II. These molecules are important indicators for some cancerous cells. Without HLA class II expression a cell may avoid an immune attack by T-cell receptors of CD4+ cells, thus the cell may continue on its cancerous course. Four malignant cell lines that lacked IRF-1 expression (WERI, Y-79, Hl734, and H322) were examined by focussing on the long (q) arm of chromosome 5 at band region q31, the IRF-1 gene locus. The results for each cell line did not indicate a deletion at 5q31. However, multiple but inconsistent abnormalities could be characterized, and future analysis is recommended.