Research Paper Volume 16, Issue 19 pp 12850—12865

Figure 4. USP4 facilitates PTC progression via the MAPK and AKT pathways. (A) Volcano plot depicting gene expression changes in tissues with high versus low USP4 expression, generated from TCGA data; (B) Summary of significantly enriched pathways in tissues exhibiting high versus low USP4 expression; (C) Western blot analysis to evaluate changes in ERK, phosphorylated ERK, AKT, and phosphorylated AKT levels in B-CPAP and TPC-1 cells following USP4 knockdown; (D) Western blot analysis to examine changes in ERK, phosphorylated ERK, AKT, and phosphorylated AKT levels in K1 and KTC-1 cells overexpressing USP4; (E) Western blot analysis to investigate changes in ERK, phosphorylated ERK, AKT, and phosphorylated AKT levels in B-CPAP and TPC-1 cells after USP4 restoration; (F, G) CCK-8 assay to evaluate the proliferative capacity of B-CPAP and TPC-1 cells following USP4 knockdown and subsequent restoration; (H) Western blot analysis to investigate alterations in ERK, phosphorylated ERK, AKT, and phosphorylated AKT levels in USP4-knockdown cells subsequently expressing either wild-type USP4 or a deubiquitination-deficient mutant (C311A); (I) CCK-8 assay to evaluate proliferation in USP4-knockdown cells subsequently expressing either wild-type USP4 or a deubiquitination-deficient mutant (C311A). All ^*p < 0.05, ^**p < 0.01, ^***p < 0.001, ^****p < 0.0001.