Figure 5.

Deptor deficiency inhibits breast cancer growth both in vitro and in vivo. Deptor deficiency (sh1 and sh2) inhibits DNA synthesis in NMuMG (A), MCF7 (B), and 4T07 (C) cells as determined by [³H]thymidine incorporation. Data are mean (± SEM; n = 3; *P < .05), except for C (n = 2). (D) Parental (scram) and Deptor-deficient (shDeptor) 4T07 cells were inoculated into the lateral tail vein of syngeneic BALB/c mice, and pulmonary tumor growth was monitored by longitudinal bioluminescence imaging as indicated. Data are mean (± SEM; n = 5; *P < .0005, **P < .03). Lungs were isolated at the time of sacrifice to visualize surface (E, arrowheads) and embedded metastases by H&E staining (F). (G) Lungs were dissociated into single cells and cultured ex vivo to monitor Deptor expression by immunoblot analysis, which demonstrated maintenance of Deptor deficiency in pulmonary-derived 4T07 cells.