The density of FRβ+ immune cells inthe tumor microenvironment was not directly associated with the tumor-targetingefficacy of the folate-functionalized cyclodextrin nanoparticles.The lung was determined as a preferential site of accumulation forfolate-functionalized nanoparticles, wherein FRβ+CD206+ macrophages significantly engulfed cyclodextrinnanoparticles. The gene discussed is FOLR2; the disease is neoplasm.