FBXW7 and renal cell carcinoma: Interestingly, the mRNA and protein levels of FBXW7 were pronouncedly decreased after up-regulation of miR-223-3p expression, but increased when miR-223-3p was down-regulated (Figure 6F–I), confirming that miR-223-3p could modulate the expression of FBXW7. In RCC cell lines, the expression of FBXW7 was generally reduced compared with HK2 cells (Figure 6J).