To determine the role of Hippo pathway mediators and TGFβ signaling on OSA cell viability, TAZ and YAP were depleted in three cell lines using siRNA (siTAZ and siYAP), and the cells were subsequently treated or not with TGFβ, followed by exposure (or not) to Doxorubicin, a drug commonly used for SOC of canine osteosarcoma [2], and one that in our hands has been reliable for in vitro experimentation. The gene discussed is TGFB1; the disease is osteosarcoma.