New insights into targeting hepatic cystogenesis in autosomal dominant polycystic liver and kidney disease.

Introduction: Polycystic liver disease (PLD) is a rare disease defined by the growth of hepatic cysts and occurs either isolated or as an extrarenal manifestation of polycystic kidney disease. While surgery has been the mainstay in treatment of symptomatic PLD, recently discovered regulatory mechanisms affecting hepatic cystogenesis provide potential new therapies to reduce hepatic cyst burden.Areas covered: This review summarizes intracellular pathways and therapeutic targets involved in hepatic cystogenesis. While drugs that target cAMP, mTOR and bile acids were evaluated in clinical trials, investigation in autophagy, Wnt and miRNA signaling pathways are still in the pre-clinical phase. Recent epidemiological data present female hormones as a promising therapeutic target. Additionally, therapeutic advances in renal cystogenesis are reviewed for their potential application in treatment of hepatic cysts.Expert opinion: Further elucidation of the pathophysiology of hepatic cystogenesis is needed to provide additional targets and improve the efficacy of current treatments. The most promising therapeutic target in PLD is the female hormone pathway, given the increased severity in women and the harmful effects of exogenous estrogens. In addition, combining current pharmaceutical and surgical therapies can lead to improved outcomes. Lastly, the rarity of PLD creates the need to share expertise internationally.