CDKN1A and systemic lupus erythematosus: For example, methylation of T lymphocyte genes in lupus [49], the tumor suppressor gene Par-4 in transformed epithelial cells [50] and p16(INK4A), p21(WAF1) [51] and hMLH1[52] genes in colon cancer cells was found to be closely linked to the MAP kinase pathway with BRAF mutation.