To further test the biological and clinical relevance of tamoxifen, combination of tamoxifen and ISA‐2011B together for targeted treatment of castration‐resistant PCa, we employed xenograft mouse model bearing castration‐resistant tumor PC‐3 with elevated level of ERα and constitutively high levels of PIP5K1α/pSer‐473 Akt. The gene discussed is ESR1; the disease is neoplasm.