Fig. 4

Mir-155-5p inhibits SOX1 leading to activation of the Raf/MEK/ERK pathway. A Cells were transfected with lentiviral negative control vector (NC-SOX1) or lentiviral SOX1 (LV-SOX1) for 72 h. Protein expressions of SOX1, HES1, PROX1, p-AKT, p-JNK, and p-P38 were examined by Western blot. B Above panel: protein levels of ERK and p-ERK in HUCCT-1 and TFK-1 cells transfected with miR-negative control (miR-NC), miR-155-5p-mimic (miR-155-5p), and miR-155-5p-inhibitor (miR-155-5pI). Below panel: TFK-1 and HUCCT-1 cells was treated with different concentrations of miR-155-5pI. The protein level of ERK and p-ERK were detected by Western blot. C Protein levels of central members of MAPK/ERK signaling (RAF, p-RAF, MEK, p-MEK, ERK and p-ERK) and downstream of ERK (PCNA) in TFK-1 and HUCCT-1 cells were detected by Western blot. D TFK-1 and HUCCT-1 cells was transfected with miR-negative control (miR-NC) and miR-15-5p inhibitor (miR-155-5pI), then protein levels of central members of MAPK/ERK signaling (RAF, p-RAF, MEK, p-MEK, ERK and p-ERK) and PCNA were detected by Western blot. E TFK-1 and HUCCT-1 cells was transfected with lenvisual carrying SOX1-RNAi (SOX1-KD), then protein levels of central members of MAPK/ERK signaling (RAF, p-RAF, MEK, p-MEK, ERK and p-ERK) and PCNA were detected by Western blot. F Cells were infected with NC-SOX1, LV-SOX1, LV-SOX1  +  NC-ERK and LV-SOX1  +  LV-ERK, and then detect changes in ERK and PCNA protein levels by western blot. G Protein levels of central members of MAPK/ERK signaling (RAF, p-RAF, MEK, p-MEK, ERK and p-ERK) was detected in xenograft tumor samples which had been transfected with NC-SOX1 and LV-SOX1