To determine if STAU2 is a downstream factor in the CHK1 pathway as suggested by the BioID2 assay, we treated the non-transformed hTERT-RPE1 and the cancer HCT116 cells with the CHK1 inhibitor PF-477736 (PF47) for 8 h (Fig. 4a). This evidence concerns the gene STAU2 and cancer.