Patients with acute-on-chronic liver failure (ACLF) represent a heterogeneous population. The aim of the study is to identify distinct groups according to the etiologies of precipitating events. A total of 405 ACLF patients were identified from 1,361 patients with cirrhosis with acute decompensation and categorized according to the types of acute insults. Clinical characteristics and prognosis between the hepatic group and extrahepatic group were compared, and the performance of prognostic models was tested in different groups. Two distinct groups (hepatic-ACLF and extrahepatic-ACLF) were identified among the ACLF population. Hepatic-ACLF was precipitated by hepatic insults and had relatively wellcompensated cirrhosis with frequent liver and coagulation failure. In contrast, extrahepatic-ACLF was exclusively precipitated by extrahepatic insults, characterized by more severe underlying cirrhosis and high occurrence of extrahepatic organ failures (kidney, cerebral, circulation, and respiratory systems). Both groups had comparably high short-term mortality (28-day transplant-free mortality: 48.3% vs. 50.7%; P 5 0.22); however, the extrahepatic-ACLF group had significantly higher 90-day and 1-year mortality (90-day: 58.9% vs. 68.3%, P 5 0.035; 1-year: 63.9% vs. 74.6%, P 5 0.019). In hepatic-ACLF group, the integrated Model for End-Stage Liver Disease (iMELD) score had the highest area under the receiver operating characteristic curve (auROC 5 0.787) among various prognostic models in predicting 28-day mortality, whereas CLIF-Consortium scores for ACLF patients (CLIF-C-ACLF) had the highest predictive value in the other group (auROC 5 0.779). Conclusions: ACLF precipitated by hepatic insults is distinct from ACLF precipitated by extrahepatic insults in clinical presentation and prognosis. The iMELD score may be a better predictor for hepatic-ACLF short-term prognosis, whereas CLIF-C-ACLF may be better for extrahepatic-ACLF patients. (HEPATOLOGY 2015;62:232-242)

The KDR polymorphisms may serve as novel genetic markers for the risk of coronary heart disease.

We sought to investigate how peripheral blood and tumorinfiltrating NK cells differ in patients with breast cancer and sarcoma, and if tumor-infiltrating NK cells develop immunoregulatory functions. Compared with peripheral blood NK cells, tumorinfiltrating NK cells undergo phenotypic changes and acquire the expression of several immune checkpoint receptors. The expression of these immune checkpoint molecules was significantly higher on NK cells expressing CD73. Mechanistically, NK cells and IL-10 (21, 22). More recently in the context of cancer, CD56 + CD3cells in patients with ovarian cancer suppressed the growth of T cells, as observed within an ex vivo expansion of tumor-infiltrating lymphocytes (TILs). Even though it was demonstrated that the suppression was mediated by NKp46 engagement, the underlying mechanisms of how NK cells suppress are still unclear (23). It is also still unclear how conventional NK cells can undergo a phenotypic switch to suppress other TIL populations and contribute to tumor immune escape.

Mesenchymal stem cell (MSC) transplantation alone may be insufficient for treatment of liver fibrosis because of complicated histopathological changes in the liver. Given that miR‐122 plays an essential role in liver fibrosis by negatively regulating the proliferation and transactivation of hepatic stellate cells (HSCs), this study investigated whether miR‐122 modification can improve the therapeutic efficacy of adipose tissue‐derived MSCs in treating liver fibrosis. MiR‐122‐modified AMSCs (AMSC‐122) were constructed through lentivirus‐mediated transfer of pre‐miR‐122. MiR‐122‐modified AMSCs expressed high level of miR‐122, while they retained their phenotype and differentiation potential as naïve AMSCs. AMSC‐122 more effectively suppressed the proliferation of and collagen maturation in HSCs than scramble miRNA‐modified AMSCs. In addition, AMSC‐derived exosomes mediated the miR‐122 communication between AMSCs and HSCs, further affecting the expression levels of miR‐122 target genes, such as insulin‐like growth factor receptor 1 (IGF1R), Cyclin G(1) (CCNG1) and prolyl‐4‐hydroxylase α1 (P4HA1), which are involved in proliferation of and collagen maturation in HSCs. Moreover, miR‐122 modification enhanced the therapeutic efficacy of AMSCs in the treatment of carbon tetrachloride (CCl4)‐induced liver fibrosis by suppressing the activation of HSCs and alleviating collagen deposition. Results demonstrate that miR‐122 modification improves the therapeutic efficacy of AMSCs through exosome‐mediated miR‐122 communication; thus, miR‐122 modification is a new potential strategy for treatment of liver fibrosis.