MPPE1 and neoplasm: Conventional type 1 DCs (cDC1), which are highly specialized in antigen cross-presentation to T cells, are the main Flt3L-dependent DC subtype and accordingly, Flt3L abundance in the tumor microenvironment correlates with the presence of cDC1 and the stimulation of effector T cells resulting in improved tumor immune control and clinical outcome in different types of cancers [31,32].