The invention provides methods for reducing growth and/or metastasis of androgen-independent (castration resistant) prostate cancer in a tissue in an animal. In one embodiment the method comprises administering to the animal a therapeutically effective amount of a compound that reduces the number of B cells, and/or the function of B cells, in the tissue. In yet another embodiment, the invention provides methods for reducing androgen-induced growth of prostate epithelial cells in prostate tissue in an animal. In one embodiment, the method comprises administering to the animal a therapeutically effective amount of a compound that reduces the number of B cells, and/or the function of B cells, in the tissue.
