A prospective pilot study of circulating endothelial cells as a potential new biomarker in portal hypertension.

BACKGROUND/AIMS: Peripheral circulating endothelial cells (CEC) have been proposed as a prognostic marker in cardiovascular diseases. Cirrhosis and portal hypertension are associated with vascular injury yet little is known about CEC count in these conditions. Therefore, we evaluated CEC count in patients with cirrhosis, and correlated it with markers of portal hypertension/disease severity. PATIENTS/METHODS: Fifteen patients with cirrhosis/portal hypertension and 15 matched controls were prospectively recruited for study participation. An automated rare cell analysis system was used to enumerate CEC from peripheral blood and correlated with clinical features. RESULTS: Median CEC levels were significantly higher in patients with cirrhosis as compared with controls (median [interquartile range (IQR)]; cirrhosis: 73.7 cells/4 ml [53.7-140.3]; controls: 28.7 cells/4 ml [21-58.7]; P=0.021). Ratio of CEC to platelet count (CEC/PC) also distinguished patients with cirrhosis from controls (IQR; cirrhosis: 0.723 [0.396-1.672]; controls: 0.126 [0.103-0.333]; P<0.001). Receiver operator characteristic analysis revealed that CEC cut-off of 42 cells/4 ml showed sensitivity of 87% and specificity of 74% for differentiating cirrhosis from controls (AUC: 0.74), while CEC/PC ratio at 0.21 showed sensitivity of 100% and specificity of 73% (AUC: 0.89). Furthermore, CEC/PC index was significantly elevated in patients with hepatic decompensation as defined by Child B/C (P<0.05). The intra- and interobserver variability correlation coefficients for CEC measurement were 0.9989 and 0.9986 respectively. CONCLUSION: Median CEC count and CEC/PC ratio are significantly elevated in patients with cirrhosis, with CEC/PC also increased in patients with decompensated cirrhosis. These data provide rationale for larger validation studies to assess if CEC may have prognostic utility in patients with cirrhosis and portal hypertension.

Nitric oxide regulates tumor cell cross-talk with stromal cells in the tumor microenvironment of the liver.

Tumor progression is regulated through paracrine interactions between tumor cells and stromal cells in the microenvironment, including endothelial cells and myofibroblasts. Nitric oxide (NO) is a key molecule in the regulation of tumor-microenvironment interactions, although its precise role is incompletely defined. By using complementary in vitro and in vivo approaches, we studied the effect of endothelial NO synthase (eNOS)-derived NO on liver tumor growth and metastasis in relation to adjacent stromal myofibroblasts and matrix because liver tumors maintain a rich, vascular stromal network enriched with phenotypically heterogeneous myofibroblasts. Mice with an eNOS deficiency developed liver tumors more frequently in response to carcinogens compared with control animals. In a surgical model of pancreatic cancer liver metastasis, eNOS overexpression in the tumor microenvironment attenuated both the number and size of tumor implants. NO promoted anoikis of tumor cells in vitro and limited their invasive capacity. Because tumor cell anoikis and invasion are both regulated by myofibroblast-derived matrix, we explored the effect of NO on tumor cell protease expression. Both microarray and Western blot analysis revealed eNOS-dependent down-regulation of the matrix protease cathepsin B within tumor cells, and silencing of cathepsin B attenuated tumor cell invasive capacity in a similar manner to that observed with eNOS overexpression. Thus, a NO gradient within the tumor microenvironment influences tumor progression through orchestrated molecular interactions between tumor cells and stroma.

Deregulation of miR-34a and Its Chaperon Hsp70 in Hepatitis C virus-Induced Liver Cirrhosis and Hepatocellular Carcinoma Patients

Background: MicroRNA deregulation may occur during hepatocellular carcinoma (HCC) genesis and progression stages. MicroRNA-34a (miR-34a) functions as a tumor suppressor and is down-regulated or silenced in a variety of human cancers, while heat shock proteins (Hsps) play important roles in assisting protein folding and preventing both protein aggregation and transport across membranes. The present study aimed to evaluating serum expression of miR-34a and its target Hsp70 for early detection of HCC in patients with liver cirrhosis (LC), focusing on correlations with clinicopathological features. Methods: A total of 180 patients were included: 120 with HCC on top of LC (60 with either early or late HCC) and 60 patients with HCV-related LC. In addition, 60 healthy individuals were considered as controls. Real-time polymerase chain reactions were performed for expression profiling of serum miR-34a and Hsp70 and for allelic discrimination of the promotor variant (rs2763979, C/T). In addition, in silico analysis was carried out. Results: All participants were heterozygote for the promotor polymorphism. miR-34a serum levels were significantly under-expressed in LC and especially HCC patients as compared to controls. Associations with a high Child-Turcotte- Pugh (CTP) score, advanced cancer stage, and number of masses were noted. In contrast the target Hsp70 was significantly overexpressed in cancer patients but not in LC group and inversely correlated with miR-34a levels. Conclusion: Utility of circulating miRNAs as biomarkers for early detection of HCC was raised. Future large-scale studies are warranted to confirm the current findings.

SIRT-1expression is associated with expression of NANOG in patients with colorectal adenocarcinoma.

AIMS: The study aimed to investigate the quantitative expression of NANOG, p38 α , NCF2, ELF and TGF-ß genes in patients with colorectal adenocarcinoma, adenoma and normal colonic tissue and their correlation with SIRT-1 protein level expression. METHOD: This study enrolled one hundred sixty seven patients; group A: 87 patients with colonoscopic findings of no adenoma or adenocarcinoma and group B: 80 patients with colorectal mass. Consecutive colonoscopic examinations were conducted, and tissue samples were taken from the colonic lesions/masses. Total RNA was isolated and mRNA expression level of NANOG, mitogen activated p38α , Neutrophil Cytosol Factor 2 (NCF2), Embryonic Liver Fodrin (ELF) and Transforming Growth Factor Beta (TGF-ß) genes were quantified by qRT-PCR. Sirt-1 protein expression level was assessed by quantitative western blot. RESULTS: There were significantly high level of mRNA transcripts expression of the genes studied in patients with adenocarcinoma and adenoma compared with normal tissue (P value < 0.01), NANOG, NCF2, ELF and TGF-ß at a cut of > 0.314, > 0.392, 0.349 and 0.333 respectively showed sensitivity (96.5%, 98.8%, 95.3%, 98.8%) and specificity of (95.3%, 92.6%, 89.5%, 93.8%) respectively in diagnosing colonic adenocarcinoma. Sirt-1 protein level was significantly highly expressed in colorectal adenocarcinoma compared to normal and adenoma colonic tissue and positively correlated with NANOG. CONCLUSION: Over expression of NANOG, p38α , NCF2, ELF and TGF-ß genes in both cases of adenocarcinoma and adenoma could have a diagnostic value. SIRT-1 and NANOG are high correlated biological markers for diagnosis and prognosis follow up in patients with adenocarcinoma.

Comparison of circulating endothelial cell/platelet count ratio to aspartate transaminase/platelet ratio index for identifying patients with cirrhosis.

BACKGROUND/OBJECTIVES: Circulating endothelial cells (CECs) are indicative of vascular injury and correlate with severity of vascular diseases. A pilot study showed that the ratio of CEC to platelet count (CEC/PC) was effective in predicting cirrhosis. Therefore, we evaluated CEC/PC in a larger cohort of patients, correlated it with cirrhosis, and compared its operating characteristics with previously described biomarker for cirrhosis, the AST/platelet ratio index (APRI). METHODS: Fifty-three patients with cirrhosis, 20 matched healthy controls, and 9 patients with noncirrhotic liver disease were recruited. Peripheral blood sample was collected and analyzed to enumerate nucleated CEC CD146+, CD105+, CD45- using a commercial assay. RESULTS: Median CEC counts were significantly higher in patients with cirrhosis (62 cells/4 mL, interquartile range [IQR]: 43.5-121) as compared with controls (31 cells/4 mL, IQR: 22.2-40). The CEC/PC was also significantly elevated in cirrhotics (0.69, IQR: 0.39-1.48) compared with controls (0.12, IQR: 0.09-0.20) and noncirrhotics (0.21, IQR: 0.08-0.43). Receiver operator characteristic (ROC) analysis revealed that CEC cutoff value of ≥37 cells/4 mL showed sensitivity of 81% and specificity of 75% for differentiating cirrhosis from controls (area under the curve [AUC]: 0.80; 95% confidence interval [CI] 0.67-0.91). The CEC/PC ratio cutoff value of ≥0.23 showed sensitivity of 91% and specificity of 82% (AUC: 0.92; 95% CI 0.83-0.99). The APRI cutoff value of ≥0.4 showed sensitivity of 94% and specificity of 85% for differentiating cirrhosis from control patients (AUC: 0.96; 95% CI 0.90-1.0). A product of CEC and APRI, termed CAPRI (CEC-APRI), effectively distinguished patients with cirrhosis from controls; with cutoff value of ≥12.7, showing higher sensitivity of 98% and specificity of 85% (AUC: 0.98; 95% CI 0.96-1.0). CONCLUSION: The CEC/PC ratio is significantly elevated in patients with cirrhosis and demonstrates comparable operating characteristics to previously described APRI. Furthermore, CAPRI, compiled as product of CEC to APRI showed outstanding ability to distinguish patients with cirrhosis from controls, although larger studies are necessary for validation.

Neuropilin-1 promotes cirrhosis of the rodent and human liver by enhancing PDGF/TGF-beta signaling in hepatic stellate cells.

PDGF-dependent hepatic stellate cell (HSC) recruitment is an essential step in liver fibrosis and the sinusoidal vascular changes that accompany this process. However, the mechanisms that regulate PDGF signaling remain incompletely defined. Here, we found that in two rat models of liver fibrosis, the axonal guidance molecule neuropilin-1 (NRP-1) was upregulated in activated HSCs, which exhibit the highly motile myofibroblast phenotype. Additionally, NRP-1 colocalized with PDGF-receptor beta (PDGFRbeta) in HSCs both in the injury models and in human and rat HSC cell lines. In human HSCs, siRNA-mediated knockdown of NRP-1 attenuated PDGF-induced chemotaxis, while NRP-1 overexpression increased cell motility and TGF-beta-dependent collagen production. Similarly, mouse HSCs genetically modified to lack NRP-1 displayed reduced motility in response to PDGF treatment. Immunoprecipitation and biochemical binding studies revealed that NRP-1 increased PDGF binding affinity for PDGFRbeta-expressing cells and promoted downstream signaling. An NRP-1 neutralizing Ab ameliorated recruitment of HSCs, blocked liver fibrosis in a rat model of liver injury, and also attenuated VEGF responses in cultured liver endothelial cells. In addition, NRP-1 overexpression was observed in human specimens of liver cirrhosis caused by both hepatitis C and steatohepatitis. These studies reveal a role for NRP-1 as a modulator of multiple growth factor targets that regulate liver fibrosis and the vascular changes that accompany it and may have broad implications for liver cirrhosis and myofibroblast biology in a variety of other organ systems and disease conditions.