SLC5A7 and colorectal cancer: Other prior studies have demonstrated that circRNAs can exert functions as ceRNAs, circFBXW4 acts as a ceRNA for miR-338-5p, competitively binding to miR-338-5p to relieve its inhibition of SLC5A7 expression, thereby upregulating SLC5A7 levels and ultimately inhibiting the progression of colorectal cancer [45].