USP5 and lung cancer: First, we found that USP5 silencing caused a reduction in β-catenin expression at the protein level but not at the mRNA level in CL1-5 cells (Fig. 4B and Additional file 1: Figure S5B) In addition, the similar results could be observed in H23, H522, and H1299 lung cancer cells (Additional file 1: Figure S5C).