Association between MBOAT7 rs641738 polymorphism and non-alcoholic fatty liver in overweight or obese children.

BACKGROUND AND AIM: The association between non-alcoholic fatty liver (NAFL) and the variant rs641738 within the membrane bound O-acyltransferase domain-containing 7 (MBOAT7) gene is currently uncertain, especially in the paediatric population. We examined whether there is an association between this genetic variant and NAFL in a large multicentre, hospital-based cohort of Italian overweight/obese children. METHODS AND RESULTS: We studied 1760 overweight or obese children [mean age (SD): 11.1(2.9) years, z-body mass index (zBMI) 3.2(0.9)], who underwent ultrasonography for the diagnosis of NAFL. A subgroup of these children (n = 182) also underwent liver biopsy. Genotyping of the MBOAT7 rs641738 polymorphism was performed by TaqMan-Based RT-PCR system in each subject. Overall, 1131 (64.3%) children had ultrasound-detected NAFL; 528 (30%) had rs641738 CC genotype, 849 (48.2%) had rs641738 CT genotype, and 383 (21.8%) had rs641738 TT genotype, respectively. In the whole cohort, the interaction of MBOAT7 genotypes with zBMI was not associated with NAFL after adjustment for age, sex, serum triglycerides, serum alanine aminotransferase levels and patatin-like phospholipase domain-containing protein-3 (PNPLA3) genotype (adjusted-odds ratio 1.02 [95% CI 0.98-1.06]). Similarly, no association was found between MBOAT7 genotypes and NAFL after stratification by obesity status. MBOAT7 genotypes were not associated with the presence of non-alcoholic steatohepatitis or the stage of liver fibrosis in a subgroup of 182 children with biopsy-proven NAFLD. CONCLUSIONS: The results of this study did not show any significant contribution of MBOAT7 rs641738 polymorphism to the risk of having either NAFL on ultrasonography or NASH on histology in a large hospital-based cohort of Italian overweight/obese children.

Serum Fetuin-A levels in obese children with biopsy proven nonalcoholic fatty liver disease.

BACKGROUND AND AIMS: Fetuin-A has been proposed as a marker of liver damage in adults with obesity-related NAFLD. The aim of this study was to test serum fetuin-A concentrations in obese children with NAFLD diagnosed either by ultrasonography or by liver biopsy and to determine its applicability as predictive tool in pediatric NAFLD. METHODS AND RESULTS: Metabolic parameters and fetuin-A levels were investigated in 81 obese children with NAFLD diagnosed by biopsy, 79 obese children with NAFLD defined by liver ultrasonography and 23 lean subjects. Serum fetuin-A correlated significantly with age, waist circumference, systolic blood pressure, fasting insulin and 2-h postload insulin during OGTT, HOMA-IR, ISI, CRP, and apo B levels. Obese children with NAFLD detected by ultrasonography had significantly higher fetuin-A levels compared to those with normal liver. In obese children who underwent liver biopsy, no significant differences were detected in fetuin-A levels between subject with nonalcoholic steatohepatitis and those with simple steatosis. Fetuin-A was not different between obese and lean children. CONCLUSION: Fetuin-A is not related with the degree of liver damage in obese children with NAFLD and its routine measurement as marker of liver disease severity is therefore not recommended.

Nonalcoholic fatty pancreas disease and Nonalcoholic fatty liver disease: more than ectopic fat.

OBJECTIVE: The aim of this study was to evaluate the metabolic effects of fatty pancreas (nonalcoholic fatty pancreas disease - NAFPD) in a group of obese paediatric patients with nonalcoholic fatty liver disease (NAFLD). METHODS: We included 121 consecutive children with echographic evidence of hepatic steatosis. All patients underwent to abdominal ultrasound to evaluate pancreatic echogenic pattern. We divided the patients into two groups on the basis of the presence of fatty pancreas. In all patients liver function tests, lipid and gluco-insulinemic profile were evaluated. A selected subset of patients (67) underwent to liver biopsy. RESULTS: Of these 121 patients, 58 showed NAFPD and 63 patients exhibited a normal pancreatic echogenic pattern. No differences were found in age, transaminases serum levels, lipid profile and pancreatic enzymes between the two groups. The patients with NAFPD had a significantly higher z-BMI, fasting insulin, insulin resistance (HOMA-IR) and lower ISI respect to the group without fatty pancreas. The patients with fatty pancreas showed a more advanced form of liver disease, with higher values of fibrosis, ballooning and NAS score with respect to the group without NAFPD. CONCLUSIONS: Our study demonstrated that NAFPD is a frequent condition in obese paediatric patients affected by NAFLD. Our data suggest that pancreatic fat should not be considered an inert accumulation of fat, but as an additional factor able to affect glucose metabolism and severity of liver disease, increasing the risk of develop metabolic syndrome.

Urinary (1)H-NMR-based metabolic profiling of children with NAFLD undergoing VSL#3 treatment.

BACKGROUND: Nowadays, non-alcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases in children. Our recent clinical trial demonstrated that dietary and VSL#3-based interventions may improve fatty liver by ultrasound and body mass index (BMI) after 4 months. OBJECTIVES: As in this short-term trial, as in others, it is impracticable to monitor response to therapy or treatment by liver biopsy, we aimed to identify a panel of potential non-invasive metabolic biomarkers by a urinary metabolic profiling. METHODS: Urine samples from a group of 31 pediatric NAFLD patients, enrolled in a VSL#3 clinical trial, were analyzed by high-resolution proton nuclear magnetic resonance spectroscopy in combination with analysis of variance-Simultaneous Component Analysis model and multivariate data analyses. Urinary metabolic profiles were interpreted in terms of clinical patient feature, treatment and chronology pattern correlations. RESULTS: VSL#3 treatment induced changes in NAFLD urinary metabolic phenotype mainly at level of host amino-acid metabolism (that is, valine, tyrosine, 3-amino-isobutyrate or ß-aminoisobutyric acid (BAIBA)), nucleic acid degradation (pseudouridine), creatinine metabolism (methylguanidine) and secondarily at the level of gut microbial amino-acid metabolism (that is, 2-hydroxyisobutyrate from valine degradation). Furthermore, some of these metabolites correlated with clinical primary and secondary trial end points after VSL#3 treatment: tyrosine and the organic acid U4 positively with alanine aminotransferase (R=0.399, P=0.026) and BMI (R=0.36, P=0.045); BAIBA and tyrosine negatively with active glucagon-like-peptide 1 (R=-0.51, P=0.003; R=-0.41, P=0.021, respectively). CONCLUSIONS: VSL#3 treatment-dependent urinary metabotypes of NAFLD children may be considered as non-invasive effective biomarkers to evaluate the response to treatment.

Effect of fructose and 3,5-diiodothyronine (3,5-T(2)) on lipid accumulation and insulin signalling in non-alcoholic fatty liver disease (NAFLD)-like rat primary hepatocytes.

Non-alcoholic fatty liver disease (NAFLD) is nowadays considered as one of the most serious pathological conditions affecting the liver. NAFLD is supposed to be initiated by the accumulation of lipids in the liver, which finally results in an impaired hepatic insulin signalling. Many researchers have recently focused their attention on the role played by fructose as a NAFLD-triggering agent, because of the increased diffusion of fructose-sweetened food. However, epidemiological data do not permit to evaluate the role of fructose per se, because these foods are often associated with elevated energy intake and unhealthy lifestyle. In the present work, we analysed the effects of fructose on the accumulation of lipids and insulin signalling in rat primary hepatocytes. Moreover, we investigated the effect of the thyroid hormone metabolite, devoid of thyrotoxic effects, 3,5-diiodothyronine (3,5-T2) over the same parameters. To evaluate the effect on insulin signalling we took into consideration three key proteins, such as p85 subunit of phosphatidylinositol 3-kinase (PI3K), phosphatase and tensin homolog (PTEN), and Akt. Our results show that fructose in vitro, in the range of physiological concentrations, was not able to stimulate either lipid accumulation or to impair insulin signalling in our NAFLD-like rat primary hepatocytes. Our data thus support the idea that fructose per se may exert detrimental effects mainly triggering systemic effects, rather than directly affecting isolated hepatocytes. Moreover, we demonstrated that 3,5-T2, at physiological levels, reduces lipid content and triggers phosphorylation of Akt in an insulin receptor-independent manner, revealing new interesting properties as a biologically active molecule.

Randomised clinical trial: The beneficial effects of VSL#3 in obese children with non-alcoholic steatohepatitis.

BACKGROUND: Gut microbiota modifiers may have beneficial effects of non-alcoholic fatty liver disease (NAFLD) but randomised controlled trials (RCT) are lacking in children. AIM: To perform a double-blind RCT of VSL#3 vs. placebo in obese children with biopsy-proven NAFLD. METHODS: Of 48 randomised children, 44 (22 VSL#3 and 22 placebo) completed the study. The main outcome was the change in fatty liver severity at 4 months as detected by ultrasonography. Secondary outcomes were the changes in triglycerides, insulin resistance as detected by the homoeostasis model assessment (HOMA), alanine transaminase (ALT), body mass index (BMI), glucagon-like peptide 1 (GLP-1) and activated GLP-1 (aGLP-1). Ordinal and linear models with cluster confidence intervals were used to evaluate the efficacy of VSL#3 vs. placebo at 4 months. RESULTS: At baseline, moderate and severe NAFLD were present in 64% and 36% of PLA children and in 55% and 45% of VSL#3 children. The probability that children supplemented with VSL#3 had none, light, moderate or severe FL at the end of the study was 21%, 70%, 9% and 0% respectively with corresponding values of 0%, 7%, 76% and 17% for the placebo group (P < 0.001). No between-group differences were detected in triglycerides, HOMA and ALT while BMI decreased and GLP-1 and aGLP1 increased in the VSL#3 group (P < 0.001 for all comparisons). CONCLUSIONS: A 4-month supplement of VSL#3 significantly improves NAFLD in children. The VSL#3-dependent GLP-1 increase could be responsible for these beneficial effects. Trial identifier: NCT01650025 (www.clinicaltrial.gov).

Non-alcoholic fatty liver disease and hepatocellular carcinoma in a 7-year-old obese boy: coincidence or comorbidity?

BACKGROUND: Hepatocellular carcinoma (HCC) may develop from non-alcoholic fatty liver disease (NAFLD) either in the presence or in the absence of established cirrhosis. Non-cirrhotic patients with NAFLD-related HCC are usually adult, male and obese. However, this association has not been reported yet in younger age groups. Objectives In the present study, the clinical case of a 7-yaer-old obese boy with steatosis and HCC is presented. METHODS: A 7-year-old boy, with no evidence of chronic liver disease, was admitted for assessment of a liver mass. Preliminary assessment was suggestive of a combined and severe liver steatosis together with a malignant disease. RESULTS: A biopsy confirmed the suspected diagnosis of HCC; interestingly, the non-neoplastic liver was surrounded and characterized by the presence of steatosis and ballooning, and being absent of lobular inflammation and fibrosis. Chemotherapy and diet changes were conducted successfully with ultrasound characteristics suggesting improvements on both aspects: conventional liver mass resection could take place. CONCLUSIONS: This case report suggests that HCC might develop in paediatric age patients with obesity-related NAFLD, even in the absence of fibrosis.

Docosahexaenoic acid for the treatment of fatty liver: randomised controlled trial in children.

BACKGROUND AND AIM: Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease in children. We tested whether dietary supplementation with docosahexaenoic acid (DHA) can decrease liver fat content in children with NAFLD. METHODS AND RESULTS: We performed a randomized controlled trial of DHA supplementation (250 mg/day and 500 mg/day) vs. placebo in 60 children with NAFLD (20 children per group). The main outcome was the change in liver fat as detected by ultrasonography after 6, 12, 18 and 24 months of treatment. Secondary outcomes were changes in triglycerides, alanine transaminase (ALT), body mass index (BMI) and homeostasis model assessment of insulin resistance (HOMA). The odds of more severe versus less severe liver steatosis decreased to the same degree at 6 months in children treated with DHA 250 mg/day and DHA 500 mg/day vs. placebo and persisted virtually unmodified for 24 months (OR ≤ 0.02, p ≤ 0.05 for all time points). Triglycerides were lower in the DHA groups than in the placebo group at any time point and ALT was lower in these groups from month 12 onwards. HOMA was lower in the DHA 250 mg group vs. placebo at months 6 and 12. CONCLUSION: DHA supplementation improves liver steatosis in children with NAFLD. Doses of 250 mg/day and 500 mg/day of DHA appear to be equally effective in reducing liver fat content.

Energy expenditure and insulin sensitivity evaluation in obese children affected by hepatosteatosis.

OBJECTIVES: The aim of our study was to evaluate the physical and sedentary activities and energy expenditure (EE) in a group of children affected by non-alcoholic fatty liver disease (NAFLD), compared with normal and obese subjects, using a physical activity questionnaire (PAQ) and a SenseWear armband (SWA). METHODS: Forty NAFLD (10 females), 41 lean (NRM; 11 females) and 30 obese (OB; 10 females), age- and pubertal stage-matched, children were included. RESULTS: Sedentary activity (PAQ) was similar in NAFLD and NRM but less in OB, while SWA showed that NAFLD spent less time in physical activity and more in sedentary activities compared with NRM, but not with OB. Insulin sensitivity index result is related to active EE (cal kg(-1) d(-1) ) in NAFLD, while homeostatic model assessment index result was negatively related to total EE in OB. CONCLUSIONS: Regular physical activity must be encouraged in all obese children affected by NAFLD or not, and SWA might be a possible valid tool for evaluating actual EE.

Psychosocial condition after liver transplantation in children: review of the literature from 2006 to 2008.

Pediatric liver transplantation is the treatment of choice for end-stage liver disease of various causes. With most patients surviving long term after surgery, questions and concerns nowadays focus on morbidity and quality of life. Characterizing health-related quality of life (HRQOL) after liver transplantation provides a more complete estimate of the overall health of liver transplant candidates and recipients. HRQOL remains, however, a wide concept, with various interpretations in the literature, varying from medical assessment of physical status to considering various nonmedical aspects. Among the former aspects, concerns are commonly addressed about physical health and the psychological and/or social functioning of both transplanted children and their families. This detailed review of the most relevant papers analyzing of HRQOL after pediatric liver transplantation published between January 2006 and September 2008 includes the psychosocial aspects in children/adolescents, parents, and/or family members after liver transplantation, emphasizing limitations inherent to "measuring" and analyzing HRQOL aspects.

A protective effect of breastfeeding on the progression of non-alcoholic fatty liver disease.

OBJECTIVE: Non-alcoholic fatty liver disease (NAFLD) is a spectrum of liver disease characterised by accumulation of large-droplet fat in hepatocytes with possible progression to inflammation and fibrosis. Breastfeeding has benefits for child health, both during infancy and later in life, reducing the risk of manifestations of the metabolic syndrome. Here we investigated the association between early type of feeding (breastfed versus formula-fed and duration of breastfeeding) and later NAFLD development. STUDY DESIGN: We investigated 191 young Caucasian children (3-18 years old) with NAFLD consecutively enrolled between January 2003 and September 2007 in our centre. 48% of these children (n = 91) had been breastfed for a median (interquartile range) time of 8 (7) months. RESULTS: After correction for age, waist circumference, gestational age and neonatal weight, the odds of non-alcoholic steatohepatitis (NASH) (OR 0.04, 95% CI 0.01 to 0.10) and fibrosis (OR 0.32, 95% CI 0.16 to 0.65) were lower in breastfed versus not breastfed infants. Moreover, the odds of NASH (OR 0.70, exact 95% CI 0.001 to 0.87) and fibrosis (OR 0.86, exact 95% CI 0.75 to 0.98) decreased for every month of breastfeeding. CONCLUSIONS: This observational study suggests that earlier feeding habits might affect the clinical expression of NASH from 3 to 18 years later, with an apparent drug-like preventive effect of breastfeeding.

Elevated serum ALT in children presenting to the emergency unit: Relationship with NAFLD.

BACKGROUND: Non-alcoholic fatty liver disease, ranging from hepatic steatosis to necro-inflammation with or without fibrosis (non-alcoholic steatohepatitis), is a growing clinical liver disorder in children. AIM: The goals of this study were to characterize liver disorders associated with elevated aminotransferases and establish the non-alcoholic fatty liver disease/non-alcoholic steatohepatitis prevalence in hypertransaminasemic children admitted to the emergency room. METHODS: The medical records of 3280 children (2-17 years of age) admitted to the emergency room of Bambino Gesù Children's Hospital of Rome, and presenting with hypertransaminasemia were analysed retrospectively. RESULTS: Elevation of serum alanine aminotransferases was present in 897 patients. Of these, 520 (58%) spontaneously normalized alanine aminotransferases, and 179/897 (20%) maintained persistently elevated alanine aminotransferases levels. Twenty-one patients were excluded because of medication or alcohol use. In the remaining 157 patients with elevated alanine aminotransferases, obesity was found in 87 (55%), viral infections in 52 (33%) and genetic diseases in 14 (9%). Obesity-related alanine aminotransferases elevation was associated with a histological diagnosis of non-alcoholic fatty liver disease in 85% of patients. In particular, steatosis was histologically confirmed in 74 patients; 43/74 (58%) had steatohepatitis, and 12/74 (16%) had fibrosis. CONCLUSIONS: Twenty percent of children with elevated aminotransferases on routine testing may hide non-alcoholic fatty liver disease/non-alcoholic steatohepatitis. A careful diagnostic workup of persistent hypertransaminasemia in all obese subjects is warranted in the paediatric setting.

PKR is a novel functional direct player that coordinates skeletal muscle differentiation via p38MAPK/AKT pathways.

Myogenic differentiation is a highly orchestrated multistep process controlled by extracellular growth factors that modulate largely unknown signals into the cell affecting the muscle-transcription program. P38MAPK-dependent signalling, as well as PI3K/Akt pathway, has a key role in the control of muscle gene expression at different stages during the myogenic process. P38MAPK affects the activities of transcription factors, such as MyoD and myogenin, and contributes, together with PI3K/Akt pathway, to control the early and late steps of myogenic differentiation. The aim of our work was to better define the role of PKR, a dsRNA-activated protein kinase, as potential component in the differentiation program of C2C12 murine myogenic cells and to correlate its activity with p38MAPK and PI3K/Akt myogenic regulatory pathways. Here, we demonstrate that PKR is an essential component of the muscle development machinery and forms a functional complex with p38MAPK and/or Akt, contributing to muscle differentiation of committed myogenic cells in vitro. Inhibition of endogenous PKR activity by a specific (si)RNA and a PKR dominant-negative interferes with the myogenic program of C2C12 cells, causing a delay in activation of myogenic specific genes and inducing the formation of thinner myofibers. In addition, the construction of three PKR mutants allowed us to demonstrate that both N and C-terminal regions of PKR are critical for the interaction with p38MAPK and Akt. The novel discovered complex permits PKR to timely regulate the inhibition/activation of p38MAPK and Akt, controlling in this way the different steps characterizing skeletal muscle differentiation.

Hepatitis C virus core protein enhances B lymphocyte proliferation.

HCV chronic infection leads to liver diseases and also to a wide range of extrahepatic disorders including benign, but pre-lymphomatous forms (mixed cryoglobulinemia) to frank hematological neoplasia (non-Hodgkin's lymphoma). Recent data showed the involvement of p53 superfamily members in the pathogenesis of different lymphatic malignancies. In fact, tymomas and a subset of non-Hodgkin's lymphomas (NHLs) express high levels of p63. Thus, we analyzed whether alterations in p53 superfamily gene expression are observable in B lymphocytes isolated from HCV-infected patients with and without lymphoproliferative disorders. We showed, by real-time PCR, a significant induction of DNp63 mRNAs in B lymphocytes obtained from HCV-positive low grade non-Hodgkin's lymphoma patients. Since our current understanding of HCV proteins emphasizes the ability of the HCV core protein to deregulate the expression and activity of p53-related proteins, we established different B lymphocyte cell lines (Wil2-ns, Daudi and Ramos) stably expressing HCV core protein, in order to investigate the possible involvement of the viral protein in the upregulation of DNp63 in B lymphocytes. The analysis of p63 family transcripts showed no transcriptional changes for the p63 TA isoforms, whereas an increase (>5 times) of DNp63 mRNA occurred. In all cell lines, this abnormal expression was associated with a significant increase of cell proliferation that was specifically inhibited by silencing DNp63 mRNA. These findings suggest a pathogenetic role of the HCV core in HCV-related lymphomagenesis, through the induction of DNp63's pro-proliferative effects.

Enhancing the efficacy of hepatocellular carcinoma chemotherapeutics with natural anticancer agents.

Hepatocellular carcinoma (HCC) is a common cancer worldwide. A majority of HCC patients present with an unresectable or metastatic HCC and systemic therapy with cytotoxic agents provides marginal benefits. Some evidence suggests that certain natural phytochemical compounds used in conjunction with chemotherapeutic agents could enhance therapeutic efficacy by sensitizing cells to treatment.

Thr 446 phosphorylation of PKR by HCV core protein deregulates G2/M phase in HCC cells.

Hepatitis C virus (HCV) is the major causative viral agent of cirrhosis and hepatocarcinoma (HCC). HCV core protein affects cell homeostasis, playing an important role in viral pathogenesis of HCC. We investigate the effects of HCV core protein expression on cell growth in HCC cell lines. Cell cycle distribution analysis of HepG2 polyclonal core positive cells reveals a peculiar accumulation of cells in G2/M phase. Different pathways mediate G2/M arrest: such as p53 and double strand RNA protein kinase (PKR). Flow cytometry in p53-null cells demonstrates that p53 plays only a marginal role in inducing HCV core-dependent G2/M phase accumulation that seems to be significantly affected by the functional inactivation of PKR. HCC core positive cells are characterized by a significant PKR phosphorylation in Thr 446 residue, which leads deregulation of mitosis. Moreover, we observe that the overexpression of the viral protein induces an upregulation of PKR activity, which does not correlate with an increased eIF-2 phosphorylation. This uncommon behavior of PKR suggests that its activation by HCV core protein could involve alternative PKR-dependent pathways, implicated in core-dependent G2/M accumulation. The described biological effects of HCV core protein on cell cycle could be an additional viral mechanism for both HCV resistance to interferon (IFN) and HCC HCV-related pathogenesis.

Thyroid hormones regulate DNA-synthesis and cell-cycle proteins by activation of PKCalpha and p42/44 MAPK in chick embryo hepatocytes.

The molecular mechanism by which thyroid hormones exert their effects on cell growth is still unknown. In this study, we used chick embryo hepatocytes at different stages of development as a model to investigate the effect of the two thyroid hormones, T3 and T4, and of their metabolite T2, on the control of cell proliferation. We observed that T2 provokes increase of DNA-synthesis as well as T3 and T4, independently of developmental stage. We found that this stimulatory effect on the S phase is reverted by specific inhibitors of protein kinase C (PKC) and p42/44 mitogen-activated protein kinase (p42/44 MAPK), Ro 31-8220 or PD 98059. Furthermore, the treatment with thyroid hormones induces the activation of PKCalpha and p42/44 MAPK, suggesting their role as possible downstream mediators of cell response mediated by thyroid hormones. The increase of DNA-synthesis is well correlated with the increased levels of cyclin D1 and cdk4 that control the G1 phase, and also with the activities of cell-cycle proteins involved in the G1 to S phase progression, such as cyclin E/A-cdk2 complexes. Interestingly, the activity of cyclin-cdk2 complexes is strongly repressed in the presence of PKC and p42/44 MAPK inhibitors. In conclusion, we demonstrated that the thyroid hormones could modulate different signaling pathways that are able to control cell-cycle progression, mainly during G1/S transition.

Retinoic acid modulates the cell-cycle in fetal rat hepatocytes and HepG2 cells by regulating cyclin-cdk activities.

Retinoic acid (RA), the most biologically active metabolite of vitamin A, is known to modulate cell proliferation, apoptosis and differentiation, with different effects depending on the cellular context. Retinoic acid can exert its effects by directly or indirectly influencing the expression of genes involved in the control of cell proliferation. In the present report we investigate the possible correlation between the antiproliferative, differentiative and apoptotic effects previously observed on rat hepatocytes and HepG2 cells, with a possible modulation of cell-cycle regulators. We demonstrate that RA induces growth arrest and differentiation in HepG2 cells by influencing the activities of cyclin-cdk complexes involved in the regulation of G1/S transition and S-phase progression, in particular by modifying the binding of these complexes to p21 and p27 inhibitors. In fetal cells, however, the induction of apoptosis and differentiation by RA was obtained via inhibition of cyclin D1-cdk4 activity, as result of an increased binding to the p16 inhibitor. Retinoic acid also modulates c-myc and Bcl-2 expression. In conclusion, our data suggest that RA could be useful to regulate the reversion of transformed phenotype and could also be utilized as a chemiopreventive agent in cells of hepatic origin.