Snu 719

Ty82, and MKN7 cell lines were obtained from JCRB cell bank (Japan). SNU638, SNU719, SNU668, SNU216, MKN45, MKN74 and MKN1 cell lines were obtained from Korean cell line Bank (Korea). All cell lines were cultured with RPMI-1640 supplemented with 10% fetal bovine serum.

Human gastric cancer cell lines, AGS (ATCC), AZ521, MKN45, KatoIII, (RIKEN, BioResource Center, Tsukuba, Japan), SNU216, SNU484, SNU601, SNU638, SNU668 and SNU719 (Korean Cell Line Bank, Seoul, Korea) were cultured in RPMI1640 supplemented with 10% FBS. The cell proliferation rate was examined using the Alamar Blue Cell Viability Reagent (Invitrogen, Carlsbad, CA, USA). For the soft agar colony formation assay, cells were suspended in 0.33% agarose contained in the medium and seeded on 0.5% bottom agar. After 21 days of culture, soft agar was stained with Giemsa solution (Wako, Osaka, Japan) and colony numbers were scored.
Cells were transfected with pcDNA3, pcDNA-Flag-RUNX3 or pcDNA-Flag-RUNX3(R122C) vector.(6 (link)) KatoIII-R3 stable cell line was constructed by transfection with pcDNA-RUNX3 and selected with G418 (Wako) at 100 μg/mL. To knock down gene expression, cells were transfected with Silencer Select siRNA for RUNX3 or β-catenin (Ambion, Cambridge, MA, USA).
To examine the Wnt activation level, cells were cotransfected with super 8× TOPflash or Super 8× FOPflash (Addgene, Cambridge, MA, USA), together with pcDNA3, pcDNA-Flag-RUNX3 or pcDNA-Flag-RUNX3(R122C).(6 (link)) At 24 h after transfection, the luciferase activity was measured using a Luciferase assay system (Promega, Madison, WI, USA).

Both human gastric cancer cell lines, SNU-638 (the EBV-negative) and SNU-719 (the EBV-positive), were obtained from the Korea Cell Line Bank (Seoul, Korea). Cells were maintained in RPMI-1640 media supplemented with 10% FBS in a humidified 5% (v/v) CO₂ atmosphere at 37°C.