Extracellular matrix signatures of human primary metastatic colon cancers and their metastases to liver

Background: Colorectal cancer is the third most frequently diagnosed cancer and the third cause of cancer deaths in the United States. Despite the fact that tumor cell-intrinsic mechanisms controlling colorectal carcinogenesis have been identified, novel prognostic and diagnostic tools as well as novel therapeutic strategies are still needed to monitor and target colon cancer progression. We and others have previously shown, using mouse models, that the extracellular matrix (ECM), a major component of the tumor microenvironment, is an important contributor to tumor progression. In order to identify candidate biomarkers, we sought to define ECM signatures of metastatic colorectal cancers and their metastases to the liver. Methods: We have used enrichment of extracellular matrix (ECM) from human patient samples and proteomics to define the ECM composition of primary colon carcinomas and their metastases to liver in comparison with normal colon and liver samples. Results: We show that robust signatures of ECM proteins characteristic of each tissue, normal and malignant, can be defined using relatively small samples from small numbers of patients. Comparisons with gene expression data from larger cohorts of patients confirm the association of subsets of the proteins identified by proteomic analysis with tumor progression and metastasis. Conclusions: The ECM protein signatures of metastatic primary colon carcinomas and metastases to liver defined in this study, offer promise for development of diagnostic and prognostic signatures of metastatic potential of colon tumors. The ECM proteins defined here represent candidate serological or tissue biomarkers and potential targets for imaging of occult metastases and residual or recurrent tumors and conceivably for therapies. Furthermore, the methods described here can be applied to other tumor types and can be used to investigate other questions such as the role of ECM in resistance to therapy

3D molecular MR imaging of liver fibrosis and response to rapamycin therapy in a bile duct ligation rat model

Background & Aims Liver biopsy, the gold standard for assessing liver fibrosis, suffers from limitations due to sampling error and invasiveness. There is therefore a critical need for methods to non-invasively quantify fibrosis throughout the entire liver. The goal of this study was to use molecular Magnetic Resonance Imaging (MRI) of Type I collagen to non-invasively image liver fibrosis and assess response to rapamycin therapy. Methods Liver fibrosis was induced in rats by bile duct ligation (BDL). MRI was performed 4, 10, or 18 days following BDL. Some BDL rats were treated daily with rapamycin starting on day 4 and imaged on day 18. A three-dimensional (3D) inversion recovery MRI sequence was used to quantify the change in liver longitudinal relaxation rate (ΔR1) induced by the collagen-targeted probe EP-3533. Liver tissue was subjected to pathologic scoring of fibrosis and analyzed for Sirius Red staining and hydroxyproline content. Results ΔR1 increased significantly with time following BDL compared to controls in agreement with ex vivo measures of increasing fibrosis. Receiver operating characteristic curve analysis demonstrated the ability of ΔR1 to detect liver fibrosis and distinguish intermediate and late stages of fibrosis. EP-3533 MRI correctly characterized the response to rapamycin in 11 out of 12 treated rats compared to the standard of collagen proportional area (CPA). 3D MRI enabled characterization of disease heterogeneity throughout the whole liver. Conclusions EP-3533 allowed for staging of liver fibrosis, assessment of response to rapamycin therapy, and demonstrated the ability to detect heterogeneity in liver fibrosis.National Cancer Institute (U.S.) (CA140861)National Institutes of Health. National Institute for Biomedical Imaging and Bioengineering (EB009062)Sanofi Aventis (Firm

Molecular MR Imaging of Liver Fibrosis: A Feasibility Study Using Rat and Mouse Models

Background & Aims: Liver biopsy, the current clinical gold standard for fibrosis assessment, is invasive and has sampling errors, and is not optimal for screening, monitoring, or clinical decision-making. Fibrosis is characterized by excessive accumulation of extracellular matrix proteins including type I collagen. We hypothesize that molecular magnetic resonance imaging (MRI) with a probe targeted to type I collagen could provide a direct and non-invasive method of fibrosis assessment. Methods: Liver fibrosis was induced in rats with diethylnitrosamine and in mice with carbon tetrachloride. Animals were imaged prior to and immediately following i.v. administration of either collagen-targeted probe EP-3533 or non-targeted control Gd-DTPA. Magnetic resonance (MR) signal washout characteristics were evaluated from T1 maps and T1-weighted images. Liver tissue was subjected to pathologic scoring of fibrosis and analyzed for gadolinium and hydroxyproline. Results: EP-3533-enhanced MR showed greater signal intensity on delayed imaging (normalized signal enhancement mice: control = 0.39 ± 0.04, fibrotic = 0.55 ± 0.03, p <0.01) and slower signal washout in the fibrotic liver compared to controls (liver t1/2 = 51.3 ± 3.6 vs. 42.0 ± 2.5 min, p <0.05 and 54.5 ± 1.9 vs. 44.1 ± 2.9 min, p <0.01 for fibrotic vs. controls in rat and mouse models, respectively). Gd-DTPA-enhanced MR could not distinguish fibrotic from control animals. EP-3533 gadolinium concentration in the liver showed strong positive correlations with hydroxyproline levels (r = 0.74 (rats), r = 0.77 (mice)) and with Ishak scoring (r = 0.84 (rats), r = 0.79 (mice)). Conclusions: Molecular MRI of liver fibrosis with a collagen-specific probe identifies fibrotic tissue in two rodent models of disease

Host Genetics Predict Clinical Deterioration in HCV-Related Cirrhosis

Single nucleotide polymorphisms (SNPs) in the epidermal growth factor (EGF, rs4444903), patatin-like phospholipase domain-containing protein 3 (PNPLA3, rs738409) genes, and near the interleukin-28B (IL28B, rs12979860) gene are linked to treatment response, fibrosis, and hepatocellular carcinoma (HCC) in chronic hepatitis C. Whether these SNPs independently or in combination predict clinical deterioration in hepatitis C virus (HCV)-related cirrhosis is unknown. We genotyped SNPs in EGF, PNPLA3, and IL28B from liver tissue from 169 patients with biopsy-proven HCV cirrhosis. We estimated risk of clinical deterioration, defined as development of ascites, encephalopathy, variceal hemorrhage, HCC, or liver-related death using Cox proportional hazards modeling. During a median follow-up of 6.6 years, 66 of 169 patients experienced clinical deterioration. EGF non-AA, PNPLA3 non-CC, and IL28B non-CC genotypes were each associated with increased risk of clinical deterioration in age, sex, and race-adjusted analysis. Only EGF non-AA genotype was independently associated with increased risk of clinical deterioration (hazard ratio [HR] 2.87; 95% confidence interval [CI] 1.31–6.25) after additionally adjusting for bilirubin, albumin, and platelets. Compared to subjects who had 0–1 unfavorable genotypes, the HR for clinical deterioration was 1.79 (95%CI 0.96–3.35) for 2 unfavorable genotypes and 4.03 (95%CI 2.13–7.62) for unfavorable genotypes for all three loci (Ptrend<0.0001). In conclusion, among HCV cirrhotics, EGF non-AA genotype is independently associated with increased risk for clinical deterioration. Specific PNPLA3 and IL28B genotypes also appear to be associated with clinical deterioration. These SNPs have potential to identify patients with HCV-related cirrhosis who require more intensive monitoring for decompensation or future therapies preventing disease progression

A functional polymorphism in the epidermal growth factor gene predicts hepatocellular carcinoma risk in Japanese hepatitis C patients

Background: A single nucleotide polymorphism (SNP) in the epidermal growth factor (EGF) gene (rs4444903) has been associated with increased risk of cancer, including hepatocellular carcinoma (HCC). The aim of this study was to examine the relationship between the EGF SNP genotype and the development and prognosis of HCC, in a Japanese population. Methods: Restriction fragment-length polymorphism was used to determine the presence of the EGF SNP genotype in 498 patients, including 208 patients with HCC. The level of EGF messenger ribonucleic acid (mRNA) expression in cancerous tissues was measured by quantitative reverse transcription polymerase chain reaction. The correlation between the EGF SNP genotype and prognosis was statistically analyzed in the patients with HCC. Results: The proportion of the A/A, A/G, and G/G genotypes were 5.3%, 42.8%, and 51.9%, respectively, in the patients with HCC, whereas in those without HCC, they were 8.6%, 35.9%, and 55.5%, respectively, revealing that the odds ratio (OR) of developing HCC was higher in patients with a G allele (OR =1.94, P=0.080 for A/G patients and OR =1.52, P=0.261 for G/G patients, as compared with A/A patients). In particular, when the analysis was limited to the 363 patients with hepatitis C, the OR for developing HCC was 3.54 (P=0.014) for A/G patients and was 2.85 (P=0.042) for G/G patients, as compared with A/A patients. Tumoral EGF mRNA expression in G/G patients was significantly higher than that in A/A patients (P=0.033). No statistically significant differences were observed between the EGF SNP genotype and diseasefree or overall survival. Conclusion: The EGF SNP genotype might be associated with a risk for the development of HCC in Japanese patients but not with prognosis. Of note, the association is significantly stronger in patients with hepatitis C, which is the main risk factor for HCC in Japan

Mouse model of carbon tetrachloride induced liver fibrosis: Histopathological changes and expression of CD133 and epidermal growth factor

<p>Abstract</p> <p>Background</p> <p>In the setting of chronic liver injury in humans, epidermal growth factor (EGF) and EGF receptor (EGFR) are up-regulated and have been proposed to have vital roles in both liver regeneration and development of hepatocellular carcinoma (HCC). Chronic liver injury also leads to hepatic stellate cell (HSC) differentiation and a novel subpopulation of HSCs which express CD133 and exhibit properties of progenitor cells has been described in rats. The carbon tetrachloride (CCl₄)-induced mouse model has been historically relied upon to study liver injury and regeneration. We exposed mice to CCl₄to assess whether EGF and CD133+ HSCs are up-regulated in chronically injured liver.</p> <p>Methods</p> <p>CCl₄in olive oil was administered to strain A/J mice three times per week by oral gavage.</p> <p>Results</p> <p>Multiple well-differentiated HCCs were found in all livers after 15 weeks of CCl₄treatment. Notably, HCCs developed within the setting of fibrosis and not cirrhosis. CD133 was dramatically up-regulated after CCl₄treatment, and increased expression of desmin and glial fibrillary acidic protein, representative markers of HSCs, was also observed. EGF expression significantly decreased, contrary to observations in humans, whereas the expression of amphiregulin, another EGFR ligand, was significantly increased.</p> <p>Conclusions</p> <p>Species-specific differences exist with respect to the histopathological and molecular pathogenesis of chronic liver disease. CCl₄-induced chronic liver injury in A/J mice has important differences compared to human cirrhosis leading to HCC.</p

Molecular liver cancer prevention in cirrhosis by organ transcriptome analysis and lysophosphatidic acid pathway inhibition

Cirrhosis is a milieu that develops hepatocellular carcinoma (HCC), the second most lethal cancer worldwide. HCC prediction and prevention in cirrhosis are key unmet medical needs. Here we have established an HCC risk gene signature applicable to all major HCC etiologies: hepatitis B/C, alcohol, and non-alcoholic steatohepatitis. A transcriptome meta-analysis of >500 human cirrhotics revealed global regulatory gene modules driving HCC risk and the lysophosphatidic acid pathway as a central chemoprevention target. Pharmacological inhibition of the pathway in vivo reduced tumors and reversed the gene signature, which was verified in organotypic ex vivo culture of patient-derived fibrotic liver tissues. These results demonstrate the utility of clinical organ transcriptome to enable a strategy, namely, reverse-engineering precision cancer prevention