Non-alcoholic fatty liver disease (NAFLD) and its most aggressive form, non-alcoholic steatohepatitis (NASH), are causing a rise in the prevalence of hepatocellular carcinoma. Data about NAFLD/NASH and intrahepatic cholangiocarcinoma (iCCA) are few and contradictory, coming from population registries that do not correctly distinguish between NAFLD and NASH. We evaluated the prevalence of NAFLD and NASH in peritumoral tissue of resected iCCA (n = 180) and in needle biopsies of matched liver donors. Data of iCCA patients were subsequently analysed to compare NASH-related iCCA (Group A), iCCA arisen in a healthy liver (Group B) or in patients with classical iCCA risk factors (Group C). NASH was found in 22.5% of 129 iCCA patients without known risk factors and in 6.2% of matched controls (risk ratio 3.625, 95% confidence interval 1.723–7.626, p < 0.001), while NAFLD was equally represented in both groups. The overall survival of NASH-related iCCA was inferior to that of patients with healthy liver (38.5 vs. 48.1 months, p = 0.003) and similar to that of patients with known risk factors (31.9 months, p = 0.948), regardless of liver fibrosis. The multivariable Cox regression confirmed NASH as a prognostic factor (hazard ratio 1.773, 95% confidence interval 1.156–2.718, p = 0.009). We concluded that NASH (but not NAFLD) is a risk factor for iCCA and might affect its prognosis. Dissecting NASH from NAFLD by histology is necessary to correctly assess the actual role of these conditions. Prevention protocols for NASH patients should also consider the risk for iCCA and not only HCC. Mechanistic studies aimed to find a direct pathogenic link between NASH and iCCA could add further relevant information.
13 November 2020 in International Journal of Cancer
Anal squamous cell carcinoma (ASCC) is a rare tumour, but its incidence is increasing. Standard chemoradiotherapy fails to cure 20% of patients and no targeted therapy is currently approved for recurrent ASCC. The PI3K/Akt/mTOR pathway is frequently altered in this poorly characterised carcinoma. IGF2 was identified here as a key factor in ASCC oncogenesis, as IGF2 was shown to play a crucial role in the PI3K pathway with frequent (~60%) and mutually exclusive genomic alterations in IGF2, IGF1R, PTEN and PIK3CA genes. We also demonstrated that IGF2 expression is mainly due to cancer‐associated fibroblasts and that IGF2 secreted by cancer‐associated fibroblasts from ASCC samples promotes proliferation of a human ASCC cell line via IGF2 paracrine signalling. Altogether, these results highlight the key role of the IGF2/PI3K axis, and the major role of cancer‐associated fibroblasts in tumour growth via IGF2 secretion, suggesting a major role of IGF2/IGF1R inhibitors in ASCC therapies.