Phospho‐RTK arrays

A mouse phospho‐RTK array kit (R&D Systems, Minneapolis, MN, USA) was used to measure the relative level of tyrosine phosphorylation of 39 distinct receptor kinases. LM8 cells were cultured with/without TAS‐115 for 24 h and lysed using lysis buffer. For collecting the lysate from the subcutaneous tumor, or lung nodule in mice, a piece of the tumor sample was minced and homogenized in T‐PER supplemented with 1% protease/phosphatase inhibitor cocktail on ice immediately after tumor resection. The arrays were blocked with blocking buffer and incubated with 300 μg of cell lysate overnight at 4 °C. The arrays were washed, incubated with a horseradish peroxidase‐conjugated phosphotyrosine detection antibody, treated with chemiluminescent, and exposed to film.