Figure 1
RUNX1 confers cell proliferative advantage via ErbB2/HER2 signaling. (a) Growth curves of NUGC4 and MKN45 cells lentivirally-transduced with control (sh_Luc) or with RUNX1 shRNA (sh_RUNX1) in the presence of 3 μM doxycycline (n = 5). (b) Apoptotic cell death induced by RUNX1 silencing. Non-depleted and RUNX1-depleted NUGC4 and MKN45 cells were cultured in the presence of 3 μM doxycycline. Forty-eight hours after treatment, cells were harvested and apoptotic cells (Annexin V+) were scored by flow cytometric analysis (n = 5). (c) RUNX1 expressions were associated with overall survival in the gastric cancer patients. The number of subjects in RUNX1 high (top 10%) and low (bottom 10%) were n = 30 and n = 30. P = 0.048 by log-rank test. Data was retrieved from Gene Expression Omnibus (GEO), accession number; GSE62254. (d) Relative densitometric quantification of phospho-RTK array spots in RUNX1-depleted MKN45 cells compared to the control. Cells were treated with 3 μM doxycycline for 48 hours, then the cells were lysed for the phospho-RTK array. Each receptor was spotted in duplicates (see Supplementary Fig. 1c for the immunoblot image). (e) Dephosphorylation of HER2 in RUNX1-silenced NUGC4 and MKN45 cells. Non-depleted and RUNX1-depleted cells were treated as in (b). Cell lysates were analyzed by immunoblotting with the indicated antibodies. Data are mean ± SEM values. *P < 0.05, **P < 0.01, by two-tailed Student’s t-test.
