To directly examine the role in HNSCC cells of G9a-mediated H3K9 methylations in autophagy, we then restored HA-tagged wild type or catalytically defective form of G9a (DN-G9a), containing N903H and L904E mutations in the SET domain [23], into FaDu cells with G9a knockdown. This evidence concerns the gene EHMT2 and head and neck squamous cell carcinoma.