Mouse models for investigating the underlying mechanisms of nonalcoholic steatohepatitis-derived hepatocellular carcinoma

As the incidence of hepatocellular carcinoma(HCC) caused by infection with the hepatotropic viruses hepatitis B and hepatitis C decreases, greater attention has become focused on HCC caused by nonalcoholic steatohepatitis(NASH), an advanced form of nonalcoholic fatty liver disease which has shown increasing prevalence in correspondence with the overall increase in metabolic syndrome over the recent decades. Several clinical population studies have shown a positive relationship between NASH and HCC, while also providing initial insights into the underlying mechanisms of HCC development from NASH. Research into the pathological progression of NASH to HCC has advanced by use of several beneficial rodent models. In this review, we summarize the established mouse models for preclinical research of NASH-associated HCC and discuss the underlying hepatic mechanisms of NASH-related tumorigenesis identified to date that could lead to new targets for treatment and prevention.

Hepatitis C virus G1b infection decreases the number of small low-density lipoprotein particles

AIM: To investigate how hepatitis C virus(HCV) G1 b infection influences the particle number of lipoproteins.METHODS: The numbers of lipoprotein particles in fasting sera from 173 Japanese subjects, 82 with active HCV G1 b infection(active HCV group) and 91 with cleared HCV infection(SVR group), were examined. Serum lipoprotein was fractionated by high-performance liquid chromatography into twenty fractions. The cholesterol and triglyceride concentrations in each fraction were measured using Lipo SEARCH. The number of lipoprotein particles in each fraction was calculated using a newly developed algorithm, and the relationship between chronic HCV G1 b infection and the lipoprotein particle number was determined by multiple linear regression analysis.RESULTS: The median number of low-density lipoprotein(LDL) particles was significantly lower in the active HCV group [1182 nmol/L, interquartile range(IQR): 444 nmol/L] than in the SVR group(1363 nmol/L, IQR: 472 nmol/L, P < 0.001), as was that of highdensity lipoprotein(HDL) particles(14168 nmol/L vs 15054 nmol/L, IQR: 4114 nmol/L vs 3385 nmol/L, P = 0.042). The number of very low-density lipoprotein(VLDL) particles was similar between the two groups. Among the four LDL sub-fractions, the number of large LDL particles was similar between the two groups. However, the numbers of medium(median: 533.0 nmol/L, IQR: 214.7 nmol/L vs median: 633.5 nmol/L, IQR: 229.6 nmol/L, P < 0.001), small(median: 190.9 nmol/L, IQR: 152.4 nmol/L vs median: 263.2 nmol/L, IQR: 159.9 nmol/L; P < 0.001), and very small LDL particles(median: 103.5 nmol/L, IQR: 66.8 nmol/L vs median: 139.3 nmol/L, IQR: 67.3 nmol/L, P < 0.001) were significantly lower in the active HCV group than in the SVR group, respectively. Multiple linear regression analysis indicated an association between HCV G1 b infection and the decreased numbers of medium, small, and very small LDL particles. However, active HCV infection did not affect the number of large LDL particles or any sub-fractions of VLDL and HDL particles.CONCLUSION: HCV G1 b infection decreases the numbers of medium, small, and very small LDL particles.

High level of serum cholesteryl ester transfer protein inactive hepatitis C virus infection

AIM: To determine the significance of cholesteryl ester transfer protein(CETP) in lipoprotein abnormalities in chronic hepatitis C virus(HCV) infection.METHODS: We evaluated the significance of the serum concentration of CETP in 110 Japanese patients with chronic HCV infection. Fifty-five patients had active HCV infection, and HCV eradication had been achieved in 55. The role of CETP in serum lipoprotein abnormalities, specifically, in triglyceride(TG) concentrations in the four major classes of lipoproteins, was investigated using Pearson correlations in conjunction with multiple regression analysis and compared them between those with active HCV infection and those in whom eradication had been achieved. RESULTS: The serum CETP levels of patients with active HCV infection were significantly higher than those of patients in whom HCV eradication was achieved(mean ± SD, 2.84 ± 0.69 μg/m L vs 2.40 ± 1.00 μg/m L, P = 0.008). In multiple regression analysis, HCV infection status(active or eradicated) was an independent factor significantly associated with the serum CETP level. TG concentrations in low-density lipoprotein(mean ± SD, 36.25 ± 15.28 μg/m L vs 28.14 ± 9.94 μg/m L, P = 0.001) and high-density lipoprotein(HDL)(mean ± SD, 25.9 ± 7.34 μg/m L vs 17.17 ± 4.82 μg/m L, P < 0.001) were significantly higher in patientswith active HCV infection than in those in whom HCV eradication was achieved. The CETP level was strongly correlated with HDL-TG in patients with active HCV infection(R = 0.557, P < 0.001), whereas CETP was not correlated with HDL-TG in patients in whom HCV eradication was achieved(R =-0.079, P = 0.56). CONCLUSION: Our results indicate that CETP plays a role in abnormalities of lipoprotein metabolism in patients with chronic HCV infection.

Pancreatic cancer screening in patients with presumed branch-duct intraductal papillary mucinous neoplasms

Because delayed diagnosis is one of the causes of poor prognosis in pancreatic ductal adenocarcinoma(PDAC), early detection is a key for overall improvement of prognosis. Towards this end, periodic screening is recommended for individuals considered high-risk for PDAC. Advances in diagnostic imaging modalities have increased the frequency of incidental findings of pancreatic cysts,including the intraductal papillary mucinous neoplasm(IPMN)-a major risk factor of PDAC, having 1% annual prevalence of concomitance with IPMN.Proper retainment of patients with IPMN and regular follow-up by routine imaging examination will likely improve early detection and better prognosis of PDAC. Unfortunately, current guidelines only address management of PDAC derived from IPMN and overlook PDAC concomitant with IPMN. Screening of patients with IPMN, by endoscopic ultrasonography(currently the most reliable modality for detecting small PDAC), may facilitate early detection of both IPMNderived and-concomitant PDAC. Prospective studies to evaluate the usefulness of endoscopic ultrasonography in screening of IPMN-concomitant PDAC will also help in determining the optimal surveillance strategy for more widespread applications.