Table III.

Defects Involved in IFN Resistance

•Lack of JAK1 activity •Mutation in JAK1 •Downregulated expression of IRF1 and STAT1 •Loss or aberrant STAT1, STAT3, JAK1, and JAK2 phosphorylation •Altered SOCS1/3 expression •Methylation of IRF1 •Impaired binding of IRF1 to the ISRE •Reduced expression of IRF1 •Loss of IFN‐γR expression