However, the study of Kim et al. suggested that TREM2 might also acted as a tumor suppressor in some human malignancies, because they detected that TREM2 significantly inhibited the proliferation of colon cancer cells by retarding cell cycle progression and suppressed the tumorigenicity of colon cancer cells through reducing the mRNA expression of pro-tumor cytokines (IL-4) and increasing the mRNA expression of anti-tumor cytokines (IL-12 and IL-15) (84). Here, IL15 is linked to malignant colon neoplasm.