When the DEGs out of the epithelial whole dataset were compared with those of the mucosal whole dataset, only 1 common DEG was found (Fig 1G): KLK12, a gene encoding a secreted serine protease involved in angiogenesis, was upregulated by 4.2-fold in the epithelium (p = 0.001, q = 0.018) and 2.6-fold in the mucosa of OLP subjects (p = 0.028, q = 0.43). The gene discussed is KLK12; the disease is oral lichen planus.