HA-based NPs can effectively accumulate in CRC cells throughCD44-mediated uptake and release 5-FU and β-carotene intracellularly.Thereafter, β-carotene downregulates ABCB1, ABCC9, and ABCC11mRNA and the corresponding transporter levels, increasing the intracellularamount of 5-FU and causing cell cycle arrest in the G2/M phase andapoptosis (Figure 6b). The gene discussed is ABCB1; the disease is colorectal carcinoma.