Increased Liver Size Research Articles

The effects of dual PPARα/γ agonism compared with ACE inhibition in the BTBRob/ob mouse model of diabetes and diabetic nephropathy.

The leptin‐deficient BTBRob/ob mouse develops progressive albuminuria and morphological lesions similar to human diabetic nephropathy (DN), although whether glomerular hyperfiltration, a recognized feature of early DN that may contribute to renal injury, also occurs in this model is not known. Leptin replacement has been shown to reverse the signs of renal injury in this model, but in contrast, the expected renoprotection by angiotensin‐converting enzyme (ACE) inhibition in BTBRob/ob mice seems to be limited. Therefore, to investigate the potential renal benefits of improved metabolic control in this model, we studied the effect of treatment with the dual peroxisome proliferator‐activated receptor (PPAR) α/γ agonist AZD6610 and compared it with the ACE inhibitor enalapril. AZD6610 lowered plasma glucose and triglyceride concentrations and increased liver size, but had no significant effect in reducing albuminuria, whereas enalapril did have an effect. Nephrin and WT1 mRNA expression decreased in the kidneys of BTBRob/ob mice, consistent with podocyte injury and loss, but was unaffected by either drug treatment: at the protein level, both nephrin and WT1‐positive cells per glomerulus were decreased. Mesangial matrix expansion was reduced in AZD6610‐treated mice. GFR, measured by creatinine clearance, was increased in BTBRob/ob mice, but unaffected by either treatment. Unexpectedly, enalapril‐treated mice showed intrarenal arteriolar vascular remodeling with concentric thickening of vessel walls. In summary, we found that the BTBRob/ob mouse model shows some similarities to the early changes seen in human DN, but that ACE inhibition or PPAR α/γ agonism afforded limited or no kidney protection.

Hepatocellular and developmental influences of early postnatal indomethacin in mice.

The effect of early postnatal indomethacin exposure on hepatocellular and developmental alterations in mice liver was investigated. Pups received IP injections of 0, 25, 50 and 100 mg/kg indomethacin on P0, then killed at P21 and P60. Indomethacin significantly suppressed body weight at P21, but liver weight significantly decreased only in 25 mg/kg. In contrast, liver weight and liver to body weight ratio significantly increased with increasing dose of indomethacin by P60. The restoration of liver weight was a result of proliferation, as a consequence of a significant increase in the number of uni and bi-nuclear hepatocytes per field in 25 mg/kg at P21 and no evidence of hepatocellular hypertrophy. Indomethacin had a dose-related decrease in number of hepatocytes as the result of hepatocellular hypertrophy confirmed with hepatocytes presenting large cellular and nuclear size in 50 and 100 mg/kg. Moreover, proliferation contributed to the increased liver size, since bi-nuclear hepatocytes and its ratio increased at P21 at first and then decreased by P60 with increasing in dose. Indomethacin has long term effect on liver development in a dose- and time- dependent manner. The hepatocytes during both the liver development and regeneration show significant differences in cell and nuclear number and size (Tab. 3, Fig. 2, Ref. 48).

Glucomannan- and glucomannan plus spirulina-enriched pork affect liver fatty acid profile, LDL receptor expression and antioxidant status in Zucker fa/fa rats fed atherogenic diets

ABSTRACTWe evaluated the effects of glucomannan or glucomannan plus spirulina-restructured pork (RP) on liver fatty acid profile, desaturase/elongase enzyme activities and oxidative status of Zucker fa/fa rats for seven weeks. Control (C), glucomannan (G) and glucomannan/spirulina (GS)-RP; HC (cholesterol-enriched control), HG and HGS (cholesterol-enriched glucomannan and glucomannan/spirulina-RP) experimental diets were tested. Increased metabolic syndrome markers were found in C, G and GS rats. Cholesterol feeding increased liver size, fat, and cholesterol and reduced antioxidant enzyme levels and expressions. Cholesterolemia was lower in HG and HGS than in HC. GS vs. G showed higher stearic but lower oleic levels. SFA and PUFA decreased while MUFA increased by cholesterol feeding. The arachidonic/linoleic and docosahexaenoic/alpha-linolenic ratios were lower in HC, HG, and HGS vs. C, G, and GS, respectively, suggesting a delta-6-elongase-desaturase system inhibition. Moreover, cholesterol feeding, mainly in HGS, decreased low-density-lipoprotein receptor expression and the delta-5-desaturase activity and increased the delta-9-desaturase activity. In conclusion, the liver production of highly unsaturated fatty acids was limited to decrease their oxidation in presence of hypercholesterolaemia. Glucomannan or glucomannan/spirulina-RP has added new attributes to their functional properties in meat, partially arresting the negative effects induced by high-fat-high-cholesterol feeding on the liver fatty acid and antioxidant statuses.

The informative value of non-invasive liver fibrosis markers in patients with nonalcoholic fatty liver disease

To estimate the diagnostic and informative value of clinical and laboratory parameters in the development and progression of liver fibrosis in patients with nonalcoholic fatty liver disease (NAFLD) to enhance efficiency of their treatment. An open-label case-control study included 77 patients with NAFLD. Clinical and laboratory examinations were done. To search for additional noninvasive fibrosis markers, the investigators studied the serum concentrations of insulin, leptin, adiponectin, matrix metalloproteinase-9 (MMP-9) and its inhibitors, such as tissue inhibitor of matrix metalloproteinases 1 (TIMP-1) and TIMP-2. All the patients underwent elastometry to assess the degree of liver fibrosis with the Metavir scale with the use of a Fibroscan machine. The serum levels of low-density lipoproteins, glucose, MMP-9, and leptin proved to be most informative in assessing the progression of the initial stages (1-2) of fibrosis, as were the increased liver size detected by physical examination, systolic blood pressure, carbohydrate metabolic disorders, alanine/aspartate aminotransferase levels, waist-to-hip ratio, TIMP-1, and TIMP-2 in evaluating the progression of Stage II fibrosis 2 to Stage 3. The clinical and laboratory parameters can serve as reliable noninvasive markers that reflect the progression of fibrotic changes in liver tissue.

EPERYTHROZOON OVIS INFECTIONS OF SHEEPAND GOATS IN SHALATEEN, ABU-RAMAD AND HALAEEB, RED SEA GOVERNORATE, EGYPT

An outbreak occurred in sheep and goats in triangular area (Shalateen –Abu-Ramad and Halaeeb), Red Sea Governorate, Egypt was described between January to December 2013.This outbreak showed clinical signs characterized by fever, in appetence, emaciation, anemia, icterus and ill-thrift. Clinical signs are most likely to be observed in young suckling and weaner animals. It is shown to be a complex problem attributable to many causes, some of which can be eliminated by supplementary feeding, drenching, vaccination, dipping and management. However, severe prolonged anemia accompanied by the development of ill-thrift still present in 248 animals (165 sheep and 83 goats). Infection with Eperythrozoon ovis was demonstrated in 21.42% and 12.50% of lambs and kids, 41.37 % and 28.75% of weaner sheep and goats and 10.75 % and 8.51% of adult sheep and goats respectively. When the general prevalence was analyzed by age, it was observed that weaners were mostly affected and disease was highly observed during winter and summer. Hematological examination showed macrocytic hemolytic anemia, with anisocytosis, poikilocytosis and marked left shift in erythrocyte maturation. Infected sheep and goats showed significant reduction in values of Hb, PCV and RBC while leukocytic count appeared slightly elevated. The main pathological changes in E. ovis infection were an increase in size of spleen at the peak of parasitaemia and an increase in liver size. Haemosiderin was present in livers, kidneys and spleens of all infected sheep and goats at the peak and late stages of parasitaemia.

The RSPO-LGR4/5-ZNRF3/RNF43 module controls liver zonation and size.

LGR4/5 receptors and their cognate RSPO ligands potentiate Wnt/β-catenin signalling and promote proliferation and tissue homeostasis in epithelial stem cell compartments. In the liver, metabolic zonation requires a Wnt/β-catenin signalling gradient, but the instructive mechanism controlling its spatiotemporal regulation is not known. We have now identified the RSPO-LGR4/5-ZNRF3/RNF43 module as a master regulator of Wnt/β-catenin-mediated metabolic liver zonation. Liver-specific LGR4/5 loss of function (LOF) or RSPO blockade disrupted hepatic Wnt/β-catenin signalling and zonation. Conversely, pathway activation in ZNRF3/RNF43 LOF mice or with recombinant RSPO1 protein expanded the hepatic Wnt/β-catenin signalling gradient in a reversible and LGR4/5-dependent manner. Recombinant RSPO1 protein increased liver size and improved liver regeneration, whereas LGR4/5 LOF caused the opposite effects, resulting in hypoplastic livers. Furthermore, we show that LGR4(+) hepatocytes throughout the lobule contribute to liver homeostasis without zonal dominance. Taken together, our results indicate that the RSPO-LGR4/5-ZNRF3/RNF43 module controls metabolic liver zonation and is a hepatic growth/size rheostat during development, homeostasis andregeneration.

PP2Acα positively regulates the termination of liver regeneration in mice through the AKT/GSK3β/Cyclin D1 pathway

Liver injury triggers a highly organized and ordered liver regeneration (LR) process. Once regeneration is complete, a stop signal ensures that the regenerated liver is an appropriate functional size. The inhibitors and stop signals that regulate LR are unknown, and only limited information is available about these mechanisms. A 70% partial hepatectomy (PH) was performed in hepatocyte-specific PP2Acα-deleted (PP2Acα(-/-)) and control (PP2Acα(+/+)) mice. LR was estimated by liver weight, serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels and cell proliferation, and the related cellular signals were analyzed. We found that the catalytic subunit of PP2A was markedly upregulated during the late stage of LR. PP2Acα(-/-) mice showed prolonged LR termination, an increased liver size compared to the original mass and lower levels of serum ALT and AST compared with control mice. In these mice, cyclin D1 protein levels, but not mRNA levels, were increased. Mechanistically, AKT activated by the loss of PP2Acα inhibited glycogen synthase kinase 3β (GSK3β) activity, which led to the accumulation of cyclin D1 protein and accelerated hepatocyte proliferation at the termination stage. Treatment with the PI3K inhibitor wortmannin at the termination stage was sufficient to inhibit cyclin D1 accumulation and hepatocyte proliferation. PP2Acα plays an essential role in the proper termination of LR via the AKT/GSK3β/Cyclin D1 pathway. Our findings enrich the understanding of the molecular mechanism that controls the termination of LR and provides a potential therapeutic target for treating liver injury.

Abstract A27: Epigenomic and transcriptional analyses in a Tet-Myc driven mouse model of liver cancer

Abstract The c-myc proto-oncogene is frequently overexpressed in human hepatoblastoma due to gene amplification or constitutively active Wnt signaling. High Myc levels characterize an aggressive hepatoblastoma subtype, reproduced in mice with a liver-specific tetracyclin-regulated c-myc transgene (1, 2). Here, we used an analogous mouse model (tetO-MYC/Lap-tTA; ref. 3) to study the epigenomic and transcriptional mechanisms underlying tumor progression and maintenance. Tet-Myc induction in utero resulted in rapid and fully penetrant tumorigenesis by the age of six weeks. Pre-tumoral changes were detectable already at a late embryonic stage (E18.5) with increased liver size and hepatoblast fraction. As previously described (2), tumors remained dependent on the constitutive expression of the transgene. To study transcriptional changes during tumor progression and regression, we established RNA-seq profiles in control hepatoblasts, pre-tumoral Tet-Myc hepatoblasts and tumor nodules, in the latter before and after short-term inactivation of Tet-Myc. In parallel, we used ChIP-seq to profile the genome-wide distribution of Myc, RNAPII and several histone marks (H3K4me1, H3K4me3, H3K27ac), yielding comprehensive maps of Myc binding to regulatory elements (promoters and enhancers). This unique dataset is providing the basis for mechanistic studies addressing how Myc deregulates its target genes during liver tumorigenesis: comparison of differentially expressed mRNAs and Myc-binding profiles enables us to discriminate between directly and potentially indirectly regulated genes, for which we are currently investigating the underlying molecular basis. Furthermore, our genome-wide data are allowing us to unravel potentially druggable genes and pathways regulated by Myc during hepatoblastoma progression and maintenance. Our progress in characterizing this model will be presented at the meeting.

Transcriptional profiling of chronic clinical hepatic schistosomiasis japonica indicates reduced metabolism and immune responses.

Schistosomiasis is a significant cause of human morbidity and mortality. We performed a genome-wide transcriptional survey of liver biopsies obtained from Chinese patients with chronic schistosomiasis only, or chronic schistosomiasis with a current or past history of viral hepatitis B. Both disease groups were compared with patients with no prior history or indicators of any liver disease. Analysis showed in the main, downregulation in gene expression, particularly those involved in signal transduction via EIF2 signalling and mTOR signalling, as were genes associated with cellular remodelling. Focusing on immune associated pathways, genes were generally downregulated. However, a set of three genes associated with granulocytes, MMP7, CLDN7, CXCL6 were upregulated. Differential gene profiles unique to schistosomiasis included the gene Granulin which was decreased despite being generally considered a marker for liver disease, and IGBP2 which is associated with increased liver size, and was the most upregulated gene in schistosomiasis only patients, all of which presented with hepatomegaly. The unique features of gene expression, in conjunction with previous reports in the murine model of the cellular composition of granulomas, granuloma formation and recovery, provide an increased understanding of the molecular immunopathology and general physiological processes underlying hepatic schistosomiasis.

Legal Briefs: Anemia From Rh Hemolytic Disease of the Fetus and Newborn

A 3,480-g male infant was born at 36 weeks' gestation to a 32-year-old gravida 1 para 1 woman whose pregnancy was complicated by a group B Streptococcus –positive cervical culture result and hemolytic disease of the fetus and newborn (HDFN) due to Rh incompatibility. The prior pregnancy resulted in an infant who was healthy but whose records were unavailable during litigation. On an early prenatal visit for the current pregnancy, the mother's antibody screen result was positive with a titer of 1:8, at which point the obstetrician gave her an injection of anti-Rh antibodies (Rho[D] immune globulin, sold under the brand name RhoGAM). The pregnancy was not monitored for HDFN; the antibody titers were not drawn again until the day of delivery. The plaintiff obstetrician was critical of the treating obstetrician for administering RhoGAM because the patient was already sensitized, for not following the antibody titers, and for not performing aggressive fetal surveillance required in an Rh sensitized pregnancy. He pointed out that the antibody titers of 1:32 or less require serial antibody titers every 2 to 4 weeks. When and if the titers become 64 or greater, then titers and serial amniocentesis become necessary. Because the mother experienced decreased fetal movement for 1 day, her obstetrician admitted her for an evaluation. The plaintiff experts pointed out that decreased fetal movement underscored the anemia, indicating the fetus' attempt to conserve energy. The biophysical profile was found to be 2/10, the only normal score being normal amniotic fluid volume. Of note was an increase in liver size and mild ascites on the fetal ultrasonogram. Pericardial and pleural effusions were not present. The plaintiff experts pointed out that abdominal fluid collections precede pleural and pericardial effusions in hydrops from HDFN. The antibody titer was 1:2,048. The plaintiff obstetrician pointed out that this …

Estimation of Hepatitis B Virus, Hepatitis C Virus, and Different Clinical Parameters in the Thalassemic Population of Capital Twin Cities of Pakistan.

Hepatitis B and C are serious public health problems worldwide. Thalassemia patients are dependent on blood transfusions throughout their life and are at high risk of viral infections. The aim of this study was to estimate the prevalence of hepatitis B/C infections and different clinical parameters in multitransfused thalassemia population. In this study, 262 multitransfused β-thalassemia patients were enrolled from the capital twin cities of Pakistan. The presence of hepatitis B virus (HBV)/hepatitis C virus (HCV), alanine aminotransferase (ALT) level, serum creatinine, serum ferritin, hepatomegaly, splenomegaly, and splenectomy were analyzed. The overall prevalence of HBV and HCV was 3.08% and 55.73%, respectively, with 100% of patients older than 20 years had HCV infection. The ALT levels among HBV- and HCV-positive thalassemia patients were 92.62 ± 41.57 U/L and 98 ± 63.65 U/L, respectively; creatinine values observed were 0.4 ± 0.35 mg/dL (for HBV) and 0.39 ± 0.24 mg/dL (for HCV), while serum ferritin levels were 6865.87 ± 1649.13 ng/dL (for HBV) and 5445.95 ± 3059.28 ng/dL (for HCV). A total of 74.8% and 82.20% of HBV- and HCV-positive patients had hepatomegaly with an average increase in liver size of 4.17 and 4.33 cm, respectively. Splenomegaly was observed in 64.9% and 67.12% of HBV- and HCV-positive patients with an average increase in spleen size of 4 and 4.46 cm, respectively. Splenectomy was observed among 14.50% and 15.75% of HBV- and HCV-infected thalassemia patients. There is a strong need to properly screen blood before transfusions to reduce the future load of viral hepatitis from Pakistan.

Acute Massive Hepatic Enlargement in Sickle Cell Disease

Introduction: Enlargement of the liver is a common condition in clinical practice and has multiple etiologies. Acute massive increase in liver size within a matter of 48 hrs is an unusual event. We report a case of a 25-year-old female patient with sickle cell disease who presented with right upper quadrant abdominal pain, fever, and leukocytosis of 36,000 mm3. A urine analysis suggested UTI and she was treated with antibiotics along with intravenous fluids. On the 2nd hospital day, the hemoglobin dropped to 6.8g/dl from 8.2g/dl on admission. The leukocytosis increased to 45,900 mm3 and the total bilirubin from a baseline of 9.0 mg/dl on admission, rose to 12.7 mg/dl two days later. A CT scan of the abdomen on admission showed a liver of normal size with mild intrahepatic biliary ductal dilatation. Two days later, with persistent right upper quadrant discomfort, worsening leukocytosis, and the rapid drop in hemoglobin, the patient underwent a repeat CT scan followed by MRI of the abdomen. In 2 days, the liver size had drastically increased from 17.5 cm to 20.5 cm in vertical length along the mid clavicular line. An infiltrative or cobble stone type pattern had appeared in the liver parenchyma. There was no intrahepatic or common duct dilatation. The hepatic and portal veins were patent. On subsequent vascular duplex study of the inferior vena cava (IVC), the hepatic and portal veins showed no evidence of thrombosis. Because of the patient’s deteriorating status, exchange transfusion was performed, following which, the liver function tests improved and liver size clinically diminished. This intriguing case illustrates the rare syndrome of hepatic sequestration in sickle cell disease. Our patient had an acute increase in liver size, which was not due to hepatic or portal vein thrombosis; nor was it due to cholestasis. Sickle cell disease may result in sequestration of red blood cells in the spleen or lungs. On occasion, the liver is the site of RBC sequestration. In addition to pain and a falling hematocrit, liver size increases rapidly. This sequence of events in the liver may be missed unless liver size is regularly measured. When hepatic sequestration occurs, prognosis is grave and exchange transfusion should be considered as a potentially life saving strategy. Our patient with sickle cell disease had a dramatic picture of an acutely enlarging liver, which with appropriate treatment rapidly returned to normal size.

Combined antiretroviral therapy attenuates hepatic extracellular matrix remodeling in HIV patients assessed by novel protein fingerprint markers.

Combined antiretroviral therapy (cART) attenuates hepatic fibrosis in hepatitis C virus and HIV coinfected patients. However, the role of HIV or cART on hepatic fibrosis in HIV monoinfection is discussed controversially. During liver fibrosis, matrix metalloproteinases (MMPs) degrade extracellular matrix (ECM) proteins into small soluble fragments, which reflect hepatic remodeling processes. This study used these novel biomarkers to investigate the effect of HIV and cART on hepatic fibrosis remodeling. In 249 patients with HIV monoinfection and 55 healthy controls, the serum levels of MMP-degraded collagen type III (C3M), biglycan (BGM), elastin (ELM), as well as the formation marker 7S (P4NP 7S), and MMP-degraded collagen type IV (C4M) were determined using specific ELISAs. Sixty-eight patients underwent a follow-up visit 3 years later including assessment of ECM markers and fibrosis using transient elastography (Fibroscan). C3M, BGM, C4M and P4NP 7S were significantly elevated in HIV patients compared to controls and correlated to HIV viral loads and inversely to cART duration. C4M, P4NP 7S and ELM were lower in patients under cART therapy and in patients without HIV viremia, indicating that lowering of the HIV load by cART attenuates remodeling of ECM. The levels of C3M, C4M, P4NP 7S and ELM correlated significantly with the progression of fibrosis in these patients. Specific therapy of patients with HIV monoinfection also beneficially influences liver fibrosis. These novel markers of liver fibrosis remodeling may help to monitor the hepatic effects by HIV therapy.

Isolated liver disease in a patient with DeltaF508/12TG-5T/M470V: A new face of an old disease

Isolated liver disease in a patient with DeltaF508/12TG-5T/M470V: A new face of an old disease

Does hepatic steatosis have an impact on the short term hepatic response after complete attenuation of congenital extrahepatic portosystemic shunts? A prospective study of 20 dogs.

To evaluate the relationship between hepatic steatosis and increase in liver size and resolution of shunting after surgical attenuation of congenital extrahepatic portosystemic shunts in dogs. Prospective study. Dogs (n = 20) with congenital extrahepatic portosystemic shunts. Shunts were attenuated using ameroid ring constrictors. Portal blood flow and liver volume were evaluated using computed tomography before and ≥8 weeks after surgery. Hepatic steatosis was quantified by stereological point counting of lipid droplets and lipogranulomas (LG) in liver biopsies stained with Oil-red-O. Associations between steatosis and preoperative liver volume, liver growth after surgery, and development of acquired shunts were evaluated. Acquired shunts developed in 2 dogs (10%). Dogs with larger preoperative liver volumes relative to bodyweight had fewer lipid droplets per tissue point (P = .019). LG per tissue point were significantly associated with age: 0.019 ± 0.06 for dogs <12 months versus 0.25 ± 0.49 for dogs >12 months (P = .007). There was a significant positive association between liver growth after surgery and the number of LG/month of age in dogs >12 months (P = .003). There was no association between steatosis, presence of macrosteatosis, the number of LG or development of acquired shunts. This preliminary study suggests that the presence of hepatic lipidosis and LG has no demonstrable effect on development of acquired shunts or the magnitude of increase in liver volume after attenuation of congenital extrahepatic portosystemic shunts in dogs.

Correlation between liver volume, portal vascular anatomy, and hepatic perfusion in dogs with congenital portosystemic shunt before and after placement of ameroid constrictors.

To correlate changes in hepatic volume, hepatic perfusion, and vascular anatomy of dogs with congenital extrahepatic portosystemic shunts, before and after attenuation with an ameroid constrictor. Prospective study. Dogs (n = 22) with congenital extrahepatic portosystemic shunts. CT angiography and perfusion scans were performed before and after attenuation of a portosystemic shunt with an ameroid constrictor. Changes in hepatic volume, hepatic perfusion, and vascular anatomy were measured. Portal scintigraphy was performed in 8 dogs preoperatively and 22 dogs postoperatively. Dogs with smaller preoperative liver volumes had greater increases in liver volume postoperatively compared with those with larger preoperative liver volumes. Hepatic arterial fraction was increased in dogs preoperatively and returned to normal range after shunt attenuation, and was correlated with increase in liver size and decreased shunt fraction. Three dogs with no visible portal vasculature preoperatively developed portal branches postoperatively. Dogs with smaller preoperative liver volumes had the largest postoperative increase in liver volume. Hepatic arterial perfusion and portal scintigraphy correlate with liver volume and are indicators of successful shunt attenuation. Dogs without visible vasculature on CT angiography had visible portal vasculature postoperatively.

Crosstalk of Ras and Rho: activation of RhoA abates Kras-induced liver tumorigenesis in transgenic zebrafish models

RAS and Rho small GTPases are key molecular switches that control cell dynamics, cell growth and tissue development through their distinct signaling pathways. Although much has been learnt about their individual functions in both cell and animal models, the physiological and pathophysiological consequences of their signaling crosstalk in multi-cellular context in vivo remain largely unknown, especially in liver development and liver tumorigenesis. Furthermore, the roles of RhoA in RAS-mediated transformation and their crosstalk in vitro remain highly controversial. When challenged with carcinogens, zebrafish developed liver cancer that resembles the human liver cancer both molecularly and histopathologically. Capitalizing on the growing importance and relevance of zebrafish (Danio rerio) as an alternate cancer model, we have generated liver-specific, Tet-on-inducible transgenic lines expressing oncogenic Kras(G12V), RhoA, constitutively active RhoA(G14V) or dominant-negative RhoA(T19N). Double-transgenic lines expressing Kras(G12V) with one of the three RhoA genes were also generated. Based on quantitative bioimaging and molecular markers for genetic and signaling aberrations, we showed that the induced expression of oncogenic Kras during early development led to liver enlargement and hepatocyte proliferation, associated with elevated Erk phosphorylation, activation of Akt2 and modulation of its two downstream targets, p21Cip and S6 kinase. Such an increase in liver size and Akt2 expression was augmented by dominant-negative RhoA(T19N), but was abrogated by the constitutive-active RhoA(G14V). Consequently, induced expression of the oncogenic Kras in adult transgenic fish led to the development of hepatocellular carcinomas. Survival studies further revealed that the co-expression of dominant-negative RhoA(T19N) with oncogenic Kras increased the mortality rate compared with the other single or double-transgenic lines. This study provides evidence of the previously unappreciated signaling crosstalk between Kras and RhoA in regulating liver overgrowth and liver tumorigenesis. Our results also implicate that activating Rho could be beneficial to suppress the Kras-induced liver malignancies.

Parenteral Solution of Nutritional Hepatotrophic Factors Improves Regeneration in Thioacetamide-induced Cirrhotic Livers after Partial Hepatectomy

Liver resection is a suitable option for the treatment of certain hepatic conditions, particularly hepatocarcinomas, in patients with cirrhosis. However, this disease impairs liver regeneration, which increases the risk of liver failure and postoperative death. Supportive treatments for regeneration of the remaining liver may be useful for the recovery of these patients. We demonstrated that nutritional hepatotrophic factors (NHF) is an effective regenerative stimulus for cirrhotic livers in rats subjected to partial hepatectomy (PH). The rats with thioacetamide-induced cirrhosis were subjected to PH, and they were divided into 2 groups. One group received intraperitoneal administration of NHF, and the other group received saline solution. After 12 days, biometric data, collagen content, hepatocyte regeneration (proliferation cell nuclear antigen immunochemistry), and profibrotic gene expression (Collagen-α1, matrix metalloproteinase 2, tissue inhibitor of metalloproteinase 1, and transforming growth factor beta 1) were assessed. The results indicated that the rats treated with NHF after PH had an increased liver size, a reduced amount of collagen, and a higher hepatocyte proliferation index compared with the rats that underwent PH alone. In addition, collagen-α1 gene expression was decreased in the NHF-treated rats. Thus, postoperative improvement in the liver morphology following NHF treatment may cause a significant decrease in the risk of liver failure and mortality after hepatic resection.

Abstract 1572: Influence of apc and med12 mutations on embryonic liver development in zebrafish: a potential model for investigating the role of Mediator in Wnt/β-catenin-dependent cancers.

Abstract Mutations in adenomatus polyposis coli (APC) result in overactive Wnt signaling and have been linked to colon cancer and hepatoblastoma in humans. Therefore, the Wnt pathway is an attractive target for developing cancer therapeutics. APC directs β-catenin degradation; thus, APC loss results in β-catenin accumulation and an increase in β-catenin-induced transcription. Heterozygous apc mutant zebrafish present enlarged livers at 3 days post-fertilization, and as adults they are predisposed to tumor development. Recently, the Mediator co-activator complex component, Med12, was linked to Wnt signaling. Without med12, canonical Wnt/β-catenin signaling is significantly impaired. We hypothesized that heterozygous med12 mutants will have smaller livers due to a decrease in Wnt activity. Moreover, a reduction in Wnt/β-catenin signaling due to lower levels of Med12 in double heterozygous med12;apc mutant embryos will be sufficient to rescue the large liver phenotype observed in heterozygous apc mutant embryos. In situ hybridization with lfabp probe confirmed the increased liver size in apchu745/+ embryos and showed smaller livers in med12y82/+ embryos. Importantly, the med12y82/+ mutation rescued the large liver phenotype of apchu745/+ embryos. The data suggest that med12 and apc genetically interact to regulate liver development. This interaction between med12 and apc is also likely to also play a role in the development and progression of Wnt/β-catenin-dependent cancers. Therefore, rescue of liver hyperplasia in apc mutants may serve as a model for developing anti-cancer drugs targeting WNT/β-catenin signal transduction through its interaction with MED12. Citation Format: Chamille J. Lescott, Eric Glasgow. Influence of apc and med12 mutations on embryonic liver development in zebrafish: a potential model for investigating the role of Mediator in Wnt/β-catenin-dependent cancers. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1572. doi:10.1158/1538-7445.AM2013-1572 Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.

Clinical Profile and Outcomes of Patients with β Thalassemia Major and Hepatitis C Virus Infection Undergoing an Allogeneic Stem Cell Transplant

AbstractAbstract 4160There is limited data on the prevalence, clinical profile and outcome of patients with β thalassemia major (TM) who is HCV sero-positive (HCV+) prior to an allogeneic stem cell transplant (SCT). From October, 1991 to June, 2012, 370 SCT were done for TM at our center. The median age was 7.5 years (range: 2–24) and there were 232 (62.87%) males. 209 (56.5%) belonged to Lucarelli Class III. There were 44 (11.9%) cases who were HCV+, 6 (1.6%) who were HBsAg positive and 350 (94.6%) who were CMV sero-positive at the time of pre-transplant screening.HCV+ cases were significantly older and had a significantly larger liver size. There were significantly more number of HCV+ cases who were Lucarelli Class III and the median liver enzyme and ferritin levels were higher in the HCV+ group. Table 1 summarizes these and other major differences between those who were HCV positive at diagnosis and the remaining patients. The number of graft rejections was significantly higher in the HCV+ group while the TRM was comparable between the two groups. This translated into a significantly inferior event free survival (P=0.016) though the overall survival was not significantly different (P=0.140)(Table 1). It is well recognized that patients with TM are at a high risk of developing sinusoidal obstruction syndrome (SOS) post SCT. In this series, 165 (4.6%) patients developed SOS. HCV+ cases did not have a significantly higher incidence of SOS compared to those that were HCV negative. In only 3 (6.8%) of HCV+ cases was SOS the major cause of death while SOS was a major contributory factor for death in 17 (5.2%) of the remaining cases. Among the 15 (34%) of HCV+ cases that died, the major contributory cause of death was infection (40%), graft failure (20%) and SOS (20%). On a univariate cox regression analysis, HCV+ had an adverse impact on EFS (RR=1.710; 95%CI 1.066–1.744; P=0.026). However, on a forward stepwise multivariate analysis after adjusting for conventional risk factors HCV+ status did not confer an independent adverse risk factor. Of the 29 patients who are surviving, at a median follow up of 25 months, none have had progression to chronic liver disease. 20 (69%) had a normal liver function test at last follow up while only 3 have had HCV directed therapy post transplant.From August, 2009 at our center we have been using a treosulfan based conditioning regimen for our Class III patients. Among the HCV+ cases 10 were conditioned with this regimen. This regimen was well tolerated with 100% engraftment. Two patients died, one due to sepsis and the other to GVHD. In comparison, in the historical control of HCV+ cases conditioned with a conventional busulfan based regimen where there were graft rejections in 9 (26.4%) and 13 (38.2%) deaths, the major contributory cause for death being infections (46%), SOS (23%) and graft failure (23%).In conclusion HCV+ status is a surrogate risk factor for other adverse risk factors such as older age, increased liver size and inadequate medical therapy prior to SCT. After adjusting for such risk factors HCV+ cases with TM undergoing an allogeneic SCT transplant have comparable outcomes to HCV negative cases. Use of a treosulfan based regimen is well tolerated in the HCV+ group and could potentially improve the outcome in this high risk group. [Display omitted] Disclosures:No relevant conflicts of interest to declare.