As lung macrophages do not express Clec4f (Extended Data Fig. 1f) and are not depleted in Clec4fcreR26LSL-DTR mice treated with DT (Extended Data Fig. 1j), the increase in lung metastases in KC-deficient mice is probably a consequence of the higher tumour burden in the liver, as the hepatic veins drain into the lung through the right ventricle of the heart (Fig. 1f). This evidence concerns the gene CLEC4F and neoplasm.