In vivo experiments.

Seven- to ten-week-old C57BL/6 mice were purchased from Charles River Laboratories. To generate subcutaneous tumors, 2.5 × 10⁵ (MOC2) or 1 × 10⁶ (MOC1 or MEERL) cells were injected into the right flank region of the mice. For the orthotopic model of MOC2; 4 × 10⁴ cells were injected into the buccal cavity of the mice. Tumor growth was measured every 3 days using a vernier caliper until euthanization. Mice were euthanized, and tumors were surgically removed along with spleen, draining LNs, and lungs. Tumor tissues used for Western blotting were snap-frozen. Tissues used for immunohistochemical analysis were fixed with 10% neutral buffered formalin (NBF) overnight and then stored in 70% ethanol until paraffin fixation. Tissues for flow cytometric analysis were collected in RPMI media and processed immediately. LNs and lungs were analyzed for metastases using H&E staining.