Fig. 3: Transglutaminase-2 drives metastasis.

a Immunoblot analyses for TG2 in HME2-BM cells expressing TG2-targeted shRNAs (shTG2) or an empty vector (shMT) as a control. Expression of β-tubulin (β-Tub) served as a loading control. b Cells described in a were engrafted onto the mammary fat pad of two separate groups of mice. Bioluminescent images were taken immediately after engraftment (Day 0) and 29 days later (Day 29). c Comparison of overall survival between control (shMT) and TG2-depleted (shTG2) HME-BM tumor-bearing mice. d–g Primary mammary tumors were removed 32 days after engraftment (arrows in d and f), and mice were sacrificed on day 49. Bioluminescent intensity measurements of thoracic regions of interest (ROIs; d) and whole-body ROI (f) of control (shMT) and TG2-depleted (shTG2) HME2-BM tumor-bearing mice. Upon necropsy, lungs were removed and imaged (e) separate of the body (g) to visualize pulmonary and extrapulmonary metastases. h Immunoblot analyses of TG2 overexpression in HME2 cells. Expression of GFP was used as a control, and β-tubulin (β-Tub) was assessed as a loading control. i Primary tumor growth of control (GFP) and TG2-overexpressing (TG2) HME2 tumor-bearing mice was quantified by caliper measurements. j Bioluminescent intensity measurements of thoracic ROIs of control (GFP) and TG2-overexpressing (TG2) HME2 tumor-bearing mice. (k, l) Upon necropsy, the lungs (k) and whole mouse (l) were imaged separately to visualize pulmonary and extrapulmonary metastases. Data in c, d, f, i, j are the mean ± SE or individual values of five mice per group resulting in the indicated p values. Data in j are the bioluminescent radiance values for each mouse.