Previous studies have shown that NOTCH signaling is important for cancer progression and BCSC regulation.40,41 Hairy and enhancer of split (HES) as well as hes related family bHLH transcription factor with YRPW motif (HEY) families are both normally considered primary downstream targets of NOTCH signaling and contribute to cell fate determination.42 Therefore, the protein expressions of NOTCH1/2/3 and their intracellular domains NICD1/2/3 were determined by western blotting, and mRNA levels of downstream genes in HES and HEY families were analyzed by qRT-PCR. The gene discussed is NOTCH1; the disease is cancer.