SNP rs2335555 in the PTPRN2 gene, whose mutants induced by cigarette smoking can cause lung cancer, interacts with SNPs rs6459904 (d = -0.0493±0.0209, r2d<0 = 0.2487±0.1848) and rs2952820 (d = -0.0523±0.0198, r2d<0 = 0.1930±0.0970) in ESYT2 gene, whose mutants induced by sunlight/ultraviolet radiation cause malignant melanoma. Here, PTPRN2 is linked to lung cancer.