When co-cultured with PCa cells (i.e., androgen receptor (AR)-positive and dependent LNCaP, AR-positive and independent bone metastatic C4-2B, and AR-negative bone metastatic PC3) in an androgen-deprived condition, PC3 showed attachment unaffected by medium, while both LNCaP and C4-2B had increased attachment than in the androgen-replete condition, however, only C4-2B showed significant (p < 0.001) increased attachment to bone, indicating acquisition of androgen-independent features. The gene discussed is AR; the disease is posterior cortical atrophy.