Immunohistochemical Analysis of ST2 and E-cadherin

All immunohistochemistry processes were performed as described previously [40 (link)]. Briefly, immunohistochemistry was conducted using a mouse-specific HRP/DAB (ABC) Kit with growth stimulation-expressed gene 2 (ST2) antibody (MBS7604494, Mybiosource, San Diego, CA, USA) and E-cadherin (#14472, Cell Signaling Technology, Danvers, MA, USA). Tissue sections were boiled and incubated at 4 °C with anti-ST2 and E-cadherin antibodies with a blocking solution. Sections were then exposed to biotinylated goat anti-rabbit IgG secondary antibody and DAB solution (Millipore, Billerica, MA, USA) was used for antigen labeling.