In non-small cell lung cancer, peroxisome proliferator-activated receptor γ (PPARγ), a downstream target of Wnt7A/Fzd9 signaling, inhibits non-small cell lung cancer cell proliferation by up-regulating SPRY4 expression levels through regulating SPRY4 promoter activity (29). The gene discussed is FZD9; the disease is non-small cell lung carcinoma.