To delineate the role of Stat1 in IFN mediated sensitization to apoptosis induced by Fas and therapeutically relevant drugs, we established sub-lines of the IL-6 dependent MM cell line U-266-1970 with a stable over-expression of wild type Stat1 as well as its active mutant Stat1C [23]. Here, IFNA1 is linked to Miyoshi myopathy.