TRIM9 Interacts with ZEB1 to Suppress Esophageal Cancer by Promoting ZEB1 Protein Degradation via the UPP Pathway

Figure 4

TRIM9 inhibits esophageal cancer cell migration and invasion by regulating ZEB1 via the ubiquitin-proteasome pathway. (a, b) Association of the ZEB1 and TRIM9 protein or mRNA expression levels in esophageal cancer samples. Linear regression analysis was performed to examine statistical significance. (c) WB and quantitative RT-PCR detection of ZEB1 protein and mRNA levels in KYSE-410 and KYSE-30 cell lines. Each group of cancer cells was separately transfected with TRIM9-specific shRNAs or TRIM9-specific overexpression vectors and negative control vectors. (d) TRIM9 and ZEB1 protein level detection via WB experiments on esophageal cancer cell groups separately transfected with TRIM9-specific overexpression vectors or control vectors, in combination with or without treatment of UPP inhibitors (CQ and MG132). (e) Protein level quantification by WB experiments of FLAG-tagged TRIM9 and ZEB1 in HEK-293T cells. (f, g) Coimmunoprecipitation assay on the interaction of TRIM9 with ZEB1 in KYSE-410 and HEK-293T cell lines. (h) Immunofluorescence assay and colocalization ratio quantification were performed to investigate the colocalization of TRIM9 and ZEB1 in KYSE-30 and KYSE-410 cell lines.

(a)

(b)

(c)

(d)

(e)

(f)

(g)

(h)