In this experiment, △CtCa represents the relative value of the expression of the target gene in malignant mesothelioma tissues and the expression of the internal reference, △CtCa = Ct mesothelioma target gene Ct (SMO and GLI1) mesothelioma internal reference GAPDH, △CtN represents the relative value of the expression of the target gene in benign mesothelioma tissues and the expression of the internal reference, △CtN = Ct benign mesothelioma target gene (SMO and GLI1) benign. This evidence concerns the gene GAPDH and benign mesothelioma.