CARD9 and neoplasm: Wang T. et al. (2018) showed that CARD9 was involved in controlling C. tropicalis replication in macrophages. C. tropicalis can induce differentiation of MDSCs with immunosuppressive effects, and monocultures of C. tropicalis in germ-free mice can enhance tumor load, suggesting the pro-tumorigenic properties of this fungus. In contrast, Malik et al. (2018) implied that fungal-induced CARD9 activation inhibited tumor growth by regulating IL-18 release, indicating that commensal fungi may be responsible for tumor suppressor signaling events.