DDR1 and neoplasm: To explore the applicability of DDR1 inhibitor in blocking collective OSCC cell invasion in vivo, a TW2.6 derived xenograft mouse model was carried out by subcutaneous injection of TW2.6 cells to form tumor mass ~500 mm3 in size, followed by intraperitoneal injection of DDR1-IN-1 (25 mg/kg) for five consecutive days (Figure 7a).