These data support SI as the primary driver of ACLF in cirrhosis. (Hepatology 2016;64:1249-1264).

Acute‐on‐chronic liver failure (ACLF) is characterized by acute decompensation (AD) of cirrhosis, organ failure(s), and high 28‐day mortality. We investigated whether assessments of patients at specific time points predicted their need for liver transplantation (LT) or the potential futility of their care. We assessed clinical courses of 388 patients who had ACLF at enrollment, from February through September 2011, or during early (28‐day) follow‐up of the prospective multicenter European Chronic Liver Failure (CLIF) ACLF in Cirrhosis study. We assessed ACLF grades at different time points to define disease resolution, improvement, worsening, or steady or fluctuating course. ACLF resolved or improved in 49.2%, had a steady or fluctuating course in 30.4%, and worsened in 20.4%. The 28‐day transplant‐free mortality was low‐to‐moderate (6%‐18%) in patients with nonsevere early course (final no ACLF or ACLF‐1) and high‐to‐very high (42%‐92%) in those with severe early course (final ACLF‐2 or ‐3) independently of initial grades. Independent predictors of course severity were CLIF Consortium ACLF score (CLIF‐C ACLFs) and presence of liver failure (total bilirubin ≥12 mg/dL) at ACLF diagnosis. Eighty‐one percent had their final ACLF grade at 1 week, resulting in accurate prediction of short‐ (28‐day) and mid‐term (90‐day) mortality by ACLF grade at 3‐7 days. Among patients that underwent early LT, 75% survived for at least 1 year. Among patients with ≥4 organ failures, or CLIF‐C ACLFs >64 at days 3‐7 days, and did not undergo LT, mortality was 100% by 28 days. Conclusions: Assessment of ACLF patients at 3‐7 days of the syndrome provides a tool to define the emergency of LT and a rational basis for intensive care discontinuation owing to futility. (Hepatology 2015;62:243‐252)

There is increasing evidence that the physical environment is a critical mediator of tumor behavior. Hepatocellular carcinoma (HCC) develops within an altered biomechanical environment, and increasing matrix stiffness is a strong predictor of HCC development. The aim of this study was to establish whether changes in matrix stiffness, which are characteristic of inflammation and fibrosis, regulate HCC cell proliferation and chemotherapeutic response. Using an in vitro system of “mechanically tunable” matrix‐coated polyacrylamide gels, matrix stiffness was modeled across a pathophysiologically relevant range, corresponding to values encountered in normal and fibrotic livers. Increasing matrix stiffness was found to promote HCC cell proliferation. The proliferative index (assessed by Ki67 staining) of Huh7 and HepG2 cells was 2.7‐fold and 12.2‐fold higher, respectively, when the cells were cultured on stiff (12 kPa) versus soft (1 kPa) supports. This was associated with stiffness‐dependent regulation of basal and hepatocyte growth factor–stimulated mitogenic signaling through extracellular signal‐regulated kinase, protein kinase B (PKB/Akt), and signal transducer and activator of transcription 3. β1‐Integrin and focal adhesion kinase were found to modulate stiffness‐dependent HCC cell proliferation. Following treatment with cisplatin, we observed reduced apoptosis in HCC cells cultured on stiff versus soft (physiological) supports. Interestingly, however, surviving cells from soft supports had significantly higher clonogenic capacity than surviving cells from a stiff microenvironment. This was associated with enhanced expression of cancer stem cell markers, including clusters of differentiation 44 (CD44), CD133, c‐kit, cysteine‐X‐cysteine receptor 4, octamer‐4 (CXCR4), and NANOG. Conclusion: Increasing matrix stiffness promotes proliferation and chemotherapeutic resistance, whereas a soft environment induces reversible cellular dormancy and stem cell characteristics in HCC. This has implications for both the treatment of primary HCC and the prevention of tumor outgrowth from disseminated tumor cells. (HEPATOLOGY 2011;)