We found genes including HP1α, multidrug resistance gene ABCG2 [44], ANGPTL4, APC2, u-PA, JPH3, TLN1, and TERT, and signaling pathways involved in cellular differentiation, growth, adhesion, angiogenesis, hypoxia, apoptotic, canonical Wnt, and toll-like receptor signaling pathways were differentially expressed or significantly altered in lung cancer cells upon G9a knockdown. This evidence concerns the gene APC2 and lung carcinoma.