Fig. 6

LPS activated p38/ERK-MAPK pathway to promote stemness-related gene transcription. a RT-qPCR was performed to detect TET3 mRNA level. ESCC cells were pretreated with p38, MEK and NF-κB inhibitors for 30 min, whereas the control groups were treated with DMSO instead. Cells were then stimulated with LPS (1 μg/mL) for 24 h, whereas the control groups were stimulated with PBS instead. b Western was performed to detect TET3 protein level. ESCC cells were pretreated with p38 and MEK inhibitors for 30 min, whereas the control groups were treated with DMSO instead. Cells were then stimulated with LPS (1 μg/mL) for 48 h, whereas the control groups were stimulated with PBS instead. c RT-qPCR was performed to detect stemness-related genes mRNA level in ESCC cells with LPS stimulation, together with p38 or MEK inhibitor. d ChIP-qPCR was performed to detect the binding of HOXB2 to cMYC and NANOG in ESCC cells with PBS or LPS stimulation. e Luciferase was performed to study the cMYC and NANOG promoter activity regulated by HOXB2. f A model graph summarized the mechanism for epigenetic induction of the stemness of ESCC cell through a LPS-TET3-HOXB2 signaling axis. LPS activated p38/ERK-MAPK pathway to up-regulate TET3 expression. Then TET3 increased 5hmC level in HOXB2 gene region, which promoted stemness-related gene transcription, thereby inducing the stemness of ESCC cells (ns: n (ns: no significance, *p < 0.05, **p < 0.01, ***p < 0.001)