In patients (49–71 years old) with head and neck cancer, vitamin D3 (20, 40, 60 μg/day) decreased the number of progenitor cells with suppressive phenotype, promoted the proliferation of T cells after in vitro stimulation, and increased the levels of effector cytokines (IL-12 and IFN-γ) (69). The gene discussed is IFNG; the disease is head and neck cancer.