Integrating the tissue-specificity and chronology of hereditary renal cancer predisposition

ended

Cancer cells undergo profound metabolic changes. However, little is known about whether and how metabolic changes drive cancer. The discovery that mutations of Tricarboxylic Acid (TCA) cycle enzymes in mitochondria predispose to cancer gives evidence that dysregulated metabolism could drive tumorigenesis. Amongst these, mutations in Fumarate Hydratase (FH) cause Hereditary Leiomyomatosis and Renal Cell Cancer (HLRCC), characterised by tumours of the skin and uterus, and renal cancer. Patients inherit one mutated copy of FH and loss of the wild-type (wt) allele occurs in tumours. Fumarate accumulation is the defining biochemical feature of these tumours. However, the mechanisms by which FH loss and fumarate accumulation lead to these tumours is unclear. In ONCOFUM, I want to elucidate the mechanisms that underpin tissue-specific tumorigenesis in HLRCC. I hypothesise that HLRCC occurs via a two-step process. Initially, loss of the wt allele in carriers of a FH mutation leads to FH deficiency. However, most of these cells die and only cells in tissues with the appropriate metabolic hardware survive. In the second step, FH loss in permissive tissues leads to phenotypic changes that lead to cancer. To assess this hypothesis, we will generate a mouse model where we inactivate FH in multiple tissues and elucidate the ensuing tissue-specific reprogramming. Then, using cellular models, we will investigate the molecular consequences of FH loss. In parallel, we will perform a comprehensive analysis of HLRCC tumours to find diagnostic and prognostic tools, and new anticancer targets, which will be validated in vitro and in vivo. The experimental framework developed in ONCOFUM will give unparalleled molecular insights into how cancer develops in different tissues in response to loss of FH and will lead to new therapeutic strategies for HLRCC, and, more generally for the many other cancers to which metabolic reprogramming contributes.