Lineage factor-dependent signalling by kidney cancer-associated genetic alteration

As shown by large-scale human genetic data, cancer mutations display strong tissue-selectivity, but how this selectivity arises remains unclear. Here, using experimental models, functional genomics and analysis of patient samples, we demonstrate that the lineage transcription factor paired box 8 (PAX8) is required for oncogenic signalling by two common clear cell renal cell carcinoma (ccRCC)-causing genetic alterations in humans: the germline variant rs7948643 at 11q13.3 and somatic inactivation of the von Hippel-Lindau tumour suppressor (VHL). VHL loss, observed in ~90% of ccRCCs, can lead to hypoxia-inducible factor 2 alpha (HIF2A) stabilization. We show that HIF2A is preferentially recruited to PAX8-bound transcriptional enhancers, including a pro-tumorigenic cyclin D1 (CCND1) enhancer that is controlled by PAX8 and HIF2A. The ccRCC protective allele C at rs7948643 inhibits PAX8 binding at this enhancer and downstream activation of CCND1 expression. Co-option of a PAX8-dependent physiological programme that supports proliferation of normal renal epithelial cells is also required for MYC expression from the ccRCC metastasis-associated amplicons at 8q21.3-q24.3. These results demonstrate that transcriptional lineage factors are essential for the expression of canonical oncogenes and they mediate tissue-specific cancer risk associated with somatic and inherited genetic variants