Fig. 4.

Gedatolisib does not prevent, decrease or delay metastatic disease in an ER⁺ preclinical model of breast cancer. (A). Schematic of preclinical trial design. (B) Representative image of a DTC in a Ce3D‐cleared lung, stained for GFP. Scale bar = 1 mm. A single DTC (112×) is shown in the insert. Scale bar = 20 μm. (C) Analysis of DTC burden measured in Ce3D‐cleared lungs (analyzed statistically via unpaired two‐tailed t‐test). Treatment with Gedatolisib and/or chemotherapy does not significantly alter DTC presence in the lung. Error bars represent SEM. (D) Representative images of whole‐mounted femurs stained with GFP and pan‐laminin antibodies. (E) Analysis of DTC burden in whole‐mounted femurs, normalized by area (μm²) of marrow analyzed. Data were analyzed statistically via unpaired two‐tailed t‐test. There were no significant changes in DTC burden in the bone marrow of mice across treatment groups. For cohort 1, organs were analyzed from n = 5 mice (vehicle), n = 4 mice (vehicle + AC), n = 4 mice (Gedatolisib only), and n = 6 mice (Gedatolisib + AC). Error bars represent SEM. (F) Bioluminescent images of mice 15 weeks after tumor cell inoculation. Bones (spine, hind bones, or vertebral tail bones) and adrenal glands were the most common site of metastasis. Mice that did not receive chemotherapy harbored metastases at multiple sites. Group sizes were as follows: n = 11 mice (vehicle), n = 10 mice (vehicle + AC), n = 6 mice (Gedatolisib), and n = 9 mice (Gedatolisib + AC). * animal was euthanized at week 14 postinjection. ** animal was euthanized at week 4 postinjection. (G) Kaplan–Meier plot of metastasis‐free survival. P‐values for all relevant comparisons listed in the accompanying table obtained via Log‐rank (Mantel‐Cox) test. Chemotherapy significantly improved metastasis‐free survival (P = 0.002), compared to vehicle‐treated mice. Gedatolisib treatment did not offer survival advantage compared to other treatment groups.