PROK2 and neoplasm: In contrast, N2 neutrophils are not cytotoxic, express a different repertoire of chemokines, and promote tumor growth as well as progression through the expression of high levels of immunomodulatory factors (i.e. Arginase) [22], angiogenic factors (i.e. VEGF and Bv8) [6, 23, 24], and matrix remodeling factors (i.e. MMP8 and MMP9) [25].