PCa cells (1 × 106), including PC3-vector, PC3-shTNC clones, C4-2b-vector or C4-2b-TNC cells, were injected into the prostate of 6- to 7-week-old male CB.17 scid mice (Taconic Biosciences) [55 (link)]. A total of 10 mice in each group was used, in which 5 mice per cage were randomly allocated as control or experimental group. Control and experimental groups were not blinded to the investigators. Animals were excluded from the analysis when there was no tumor take. Tumor growth was monitored by bioluminescence imaging. DNA was isolated from individual femurs using DNeasy kit. Human-specific Alu qPCR was performed to determine the number of tumor cells in each femur as previously described [11 (link)]. Animal studies were performed in compliance with protocols approved by the Institutional Animal Care and Use Committee at M.D. Anderson Cancer Center.