Fig. 4

BTG2 negatively regulates growth of BC3-p53KD tumors in primary and metastatic sites. BC3-p53WT or BC3-p53KD were implanted into mouse mammary fat pads, and tumors were harvested when they reached 0.5 cm diameter. Ribonucleic acid (RNA) was extracted from tumors, and gene expression changes were assessed with RNA-sequencing (RNA-Seq). a RNA from BC3-p53WT or BC3-p53KD tumors was reverse transcribed, and quantitative real-time polymerase chain reaction (qRT-PCR) using a probe and primer set for B cell translocation gene 2 (BTG2) was performed. p = 0.0001, t test. Each dot is a biological replicate representing one tumor from one mouse. b BTG2 or green fluorescent protein (GFP) (control) was expressed in BC3-p53KD cells by lentiviral transduction, and cells were implanted to mouse mammary fat pads. Mice were subjected to bioluminescence imaging (BLI) weekly, and total photon flux from mammary tumors was quantified at each time point. n = 5 mice (10 tumors) in each group. p <0.001 for mammary tumors 6 weeks post-engraftment, Wilcoxon rank sum test. p <0.001 using linear mixed-effect model of tumor growth over the time course. c BTG2 or GFP was expressed in BC3-p53KD as in (b), and cells were injected into mouse tail veins to model the final stages of lung metastasis. Mice were subjected to BLI weekly, and total photon flux from lungs was quantified at each time point. n = 4 mice in each group. p = 0.002, linear mixed effect model. d Total photon flux from lungs of mice in (c) was assessed with BLI ex vivo at necropsy and quantified. p = 0.001, t test. Each data point represents one mouse, n = 4 mice per group. e Hematoxylin and eosin (H & E) staining of lungs of mice in (c) and (d). All error bars represent standard error of the mean (SEM)