Fig. 5

KLF4 mediates the miR-155-driven PTGES1 transactivation. a, b Promoter activity of PTGES1 gene in MDA-MB-436(a) and Hs-578 T(b) cells with control (in blue) or miR-155 knockdown (in red). c Schematic diagram showing the KLF4-binding site on the PTGES1 promoter. Numbers indicate nucleotide positions counted from the transcription start site. d Chromatin immunoprecipitation result of KLF4 in MDA-MB-436 control or in miR-155 knockdown (miRZIP155) cells. e Relative RNA expression of KLF4 in MDA-MB-436 and Hs-578 T cells. Control (in blue) or miR-155 knockdown cells (miRZIP155, in yellow) were tested. Data on the right panel shows KLF4 protein level. f, g PTGES1 promoter reporter assay with KLF4 reconstitution, in MDA-MB-436(f) or in Hs-578 T(g) cells. The panels on right show the KLF4 protein level overexpressed. h Western blot results of KLF4 in the miR-155-high and -low TNBC specimens (n = 20)