Here, we found that EFL1 improved CD4+, CD8+, and CD49b+ T cells, and decreased Tregs, leading to reduction of inflammation and liver metastasis and mesenteric re-metastasis of breast cancer cells, suggesting that T lymphocytes infiltration was implicated in EFL1-conferred protection in breast cancer liver metastasis. The gene discussed is ITGA2; the disease is breast carcinoma.