YY1 and neoplasm: Moreover, YY1 transcriptionally activates miR-135b, which directly suppresses the core circadian regulator BMAL1, to target and repress the circadian core gene BMAL1, thereby forming a YY1/miR-135b/BMAL1 axis, inhibiting tumor cell apoptosis, and promoting gemcitabine resistance in pancreatic cancer [60].