By comparison of RNA-seq expression values in TU and corresponding NL samples of LUAD and LUSC datasets, we observed a statistically significant downregulation of SPAG6 and L1TD1 mRNA expression in lung adenocarcinomas (p < 0.0001, respectively; Fig. 1a) as well as in lung squamous cell carcinomas (p < 0.0001, respectively; Fig. 1b). Here, L1TD1 is linked to squamous cell lung carcinoma.