In vitro, breast cancer, diffuse large B-cell lymphoma and non-small cell lung cancer cells can stimulate neutrophils to release NETs by secreting cytokines such as IL-6, IL-8, granulocyte-macrophage colony-stimulating factor (GM-CSF), exosomes and hypoxia-inducible factor 1α (HIF-1α) (Figure 1) [88]. This evidence concerns the gene CSF2 and breast cancer.