The oncogenic functions of RTK pathway activation have been well‐established in cancer.[32] To identify which RTKs are specifically regulated by RAC1B, we screened changes of 49 phospho‐RTKs following RAC1B or RAC1A knockdown in the previously established osimertinib‐resistant H1975 cells (H1975‐OR), which exhibited heightened activation of EGFR and downstream EKR signaling,[31] using a phospho‐RTK antibody array. This evidence concerns the gene EGFR and cancer.