To validate the involvement of AR-target genes in DHT-stimulated AA PCa cell invasion, the invasion potentials of MDA PCa 2b and E006AA cells were assessed following siRNA-mediated knockdown of RHOA, ITGB5, or PIK3CB. All 3 genes have been previously reported as possible invasion genes associated with breast, lung, colon, testicular, and head and neck cancers [51–55]. This evidence concerns the gene PIK3CB and head and neck cancer.