Mouse xenograft tumor model

Animal studies were approved by the Institutional Animal Care and Use Committee (IACUC) and all animals were maintained in a Specific Pathogen-Free (SPF) animal facility according to the guidelines of the IACUC of Korea. Six-week-old female Immunodeficient mice (BALB/c) were purchased from Orient Bio (Seoung-Nam, Republic of Korea) and utilized in this in vivo study. Five mice were tested in each group. FaDu (2 × 10⁶) cells were subcutaneously injected or into the tongue and mice were then housed for 3 days. For the subcutaneously implanted tumor model, CBD was administered orally at 5 mg/kg body weight for 4 times in a week. Mice implanted with FaDu cells into their tongue were added to CBD (5 mg/kg) by intraperitoneal (i.p) administration 3 times per week. Cisplatin (2.5 mg/kg) was intraperitoneally injected every week. The tumor size was determined every 2–3 days and calculated using the formula: V = L × W²/2 as described⁴⁴. Tumors were weighed after animals were sacrificed at 4 weeks.