Eosinophils exert an antitumor effect; they regulate the angiogenesis process, which is essential for tumor growth, promote the normalization of tumor vessels, modulate inflammatory cell activity in the TME and exert a cytotoxic effect on malignant cells by releasing compounds such as major basic protein (MBP), eosinophil cationic protein (ECP), eosinophil-derived neurotoxin (EDN), TNF-α, and granzymes [74]. The gene discussed is MBP; the disease is neoplasm.