13-S-hydroxyoctadecadienoic acid (13(S)-HODE) and 15(S)-hydroxyeicosatetraenoic acid (15(S)-HETE), as endogenous ligands for PPARγ, were significantly reduced in NNK-induced lung cancer and could inhibit NSCLC when exogenously supplemented [99,100]. Here, PPARG is linked to lung cancer.