Establishing Patient-Derived Xenograft Models

All animal experiments were performed in accordance with EU directive 2010/63 (regional animal ethics committee of Gothenburg #36-2014). The PDXs were obtained by injecting 2 × 10⁵ cells mixed with equal volume of Matrigel (Corning, NY, USA) subcutaneously at the flank of immunocompromised, non-obese severe combined immune-deficient interleukin-2 chain receptor γ knockout mice (NOG mice; Taconic, Ry, Denmark) as described previously.^{30 (link)} Tumors were measured with caliper at regular time points and tumor volume calculated using the formula: tumor volume (mm³)=(length(mm)) × (width(mm))²/2. B16F10-luciferase cells were transplanted by subcutaneous injection. Seven days after transplantation, mice were injected with 100 μl of 30 mg/ml d-luciferin. Mice were sedated in an isofluran administrating chamber and then placed in an IVIS Lumina III XR machine (Perkin-Elmer, Norwalk, CT, USA).