Moreover, the CNG at 6p21.33, more frequently found in lesions from male patients, is where HLA-B and HLA-C are located, indicating the existence of immune factors underlying gender difference of meningioma occurrence; the CNG at 20q13.33, more frequently identified in patients with peritumoral brain edema, covers the SYCP2 gene, which is related to the depth of cervical invasion in squamous cell carcinoma (40). This evidence concerns the gene HLA-C and squamous cell carcinoma.