We found that RSPO3, ADAMTS8, DMBT1 and DOCK8 were all downregulated in squamous cell carcinoma tissues compared to non-cancerous lung tissues, whereas STMN2, TUSC3 and C8orf22 were upregulated in squamous cell carcinoma (all P < 0.001, Fig. 11). The gene discussed is PPDPFL; the disease is squamous cell carcinoma.