Preparation of Vevorisertib and Sorafenib Solutions

Vevorisertib was obtained from ArQule Inc., Burlington, MA, USA, and sorafenib for the in vitro study was purchased from Sigma-Aldrich, Germany (Bay 43-9006) and, for the in vivo study, from Bayer HealthCare, Germany (Nexavar). For the in vitro experiment, a fresh solution of the treatment was prepared every week and stored at room temperature, protected from light. The sorafenib treatment was prepared as described previously [15 (link),16 (link)]. Briefly, the sugar coating of 200 mg sorafenib tablets was dissolved in DMSO. sorafenib was mixed with 1 mL of poly-oxyl castor oil (Cremophor^® EL, Sigma-Aldrich) and 1 mL of 95% ethanol per tablet to emulsify and solubilize it. The emulsion was then diluted in purified water to obtain a 10 mg/mL solution of sorafenib suitable for oral gavage. The dose strategy for vevorisertib was based on a previous toxicity study. Vevorisertib was dissolved in a 0.01 M phosphoric acid solution to obtain a 10 mg/mL solution suitable for oral gavages with a final pH of 2.25 ± 0.15. The combination was prepared by mixing drugs just before oral gavages.