ESR2 and B-cell non-Hodgkin lymphoma: Nicotinamide phosphoribosyltransferase (NAMPT), in our experiments more than 4-fold upregulated after ESR2 knockdown in HEC-1A cells, is overexpressed in several cancer entities such as ovarian, breast, gastric, colorectal, and prostate cancer, gliomas and B-cell lymphomas [46].