Fig. 3: XCP modulates tumor growth in a context-dependent manner.

A,B Xenograft assays showing subcutaneous tumor growth of MCF-7 (A) or MDA-MB-231 (B) breast cancer cells ectopically expressing dox-inducible FLAG-GFP or XCP-FLAG (left). Tumor weight at end of experiment is shown (right). Animals injected with MCF-7 cells had E2-pellet implantations at the back of the neck to promote growth of MCF-7 cells in vivo. All animals were fed doxycycline in their chow. Each point represents the mean ± SEM. For MCF-7, GFP n = 7 and XCP n = 7; For MDA-MB-231, GFP n = 8 and XCP n = 8. Significance was calculated using unpaired t-test. C,D Expression of FLAG-GFP or XCP-FLAG in tumor tissue was validated from MCF-7 (C) or MDA-MB-231 (D) xenograft tumors by Western blot (left) and RT-qPCR (right). For Western blot, 3 representative tumors from each group are shown. β-tubulin was used as a loading control. For RT-qPCR, the average of all tumors from each group is shown. RNA levels were quantified by normalizing to housekeeping gene RPL19 mRNA. Each bar represents the mean + SEM. For MCF-7, GFP n = 7 and XCP n = 7; For MDA-MB-231, GFP n = 8 and XCP n = 8. [See also Fig. S3].