FH and hereditary leiomyomatosis and renal cell cancer: Immunohistochemical analysis of FH-deficient tumors and cysts has shown a striking direct relationship between FH inactivation and an increase in 2SC proteins, which is absent in non-HLRCC tumors and normal tissue controls and has provided a potentially robust diagnostic biomarker for FH-deficiency in cells and tissues (Bardella et al., 2011).