characterisation of transcription factor profiles in polycystic kidney disease (pkd): identification and validation of stat3 and runx1 in the injury/repair response and pkd progression

Autosomal dominant polycystic kidney disease (adpkd) is the most common genetic renal disease, caused in the majority of the cases by a mutation in either the pkd1 or the pkd2 gene. adpkd is characterised by a progressive increase in the number and size of cysts, together with fibrosis and distortion of the renal architecture, over the years. this is accompanied by alterations in a complex network of signalling pathways. however, the underlying molecular mechanisms are not well characterised. previously, we defined the pkd signature, a set of genes typically dysregulated in pkd across different disease models from a meta-analysis of expression profiles. given the importance of transcription factors (tfs) in modulating disease, we focused in this paper on characterising tfs from the pkd signature. our results revealed that out of the 1515 genes in the pkd signature, 92 were tfs with altered expression in pkd, and 32 of those were also implicated in tissue injury/repair mechanisms. validating the dysregulation of these tfs by qpcr in independent pkd and injury models largely confirmed these findings. stat3 and runx1 displayed the strongest activation in cystic kidneys, as demonstrated by chromatin immunoprecipitation (chip) followed by qpcr. using immunohistochemistry, we showed a dramatic increase of expression after renal injury in mice and cystic renal tissue of mice and humans. our results suggest a role for stat3 and runx1 and their downstream targets in the aetiology of adpkd and indicate that the meta-analysis approach is a viable strategy for new target discovery in pkd.