Serum clusterin as a marker for diagnosing hepatocellular carcinoma

Background: Approximately 80% of patients with hepatocellular carcinoma (HCC) areuntreatable because of advanced tumor stages at presentation. Therefore, finding newer markers for screening and diagnosing HCC is of utmost importance. Clusterin (CLU) is a 449 amino acid, heterodimeric glycoprotein with a plausible role in the regeneration, migration, and anti-apoptosis of tumor cells. It has been implicated in many malignancies such as prostate and pancreatic adenocarcinomas, but its role in HCC is not well defined.Objective: We aimed to evaluate the diagnostic performance of serum CLU level in diagnosing HCC on top of hepatitis C virus-related liver cirrhosis, and comparing it to that of alpha fetoprotein (AFP).Methods: Twenty cases of apparently healthy subjects, 27 cases of hepatitis C virus-related liver cirrhosis (CHC cases), and 44 HCC cases on top of hepatitis C virus-related liver cirrhosis were included in this study. Serum CLU concentration was determined using a quantitative sandwich enzyme immunoassay technique.Results: Serum clusterin level showed a significant increase in the HCC group compared to the control group (151.96 ± 32.74 vs. 111.40 ±27.46) and to the CHC group (151.96 ± 32.74 vs. 89.12 ±31.62), while a significant decrease in serum clusterin level was found in the CHC group compared to the control group (89.12± 31.62 vs. 111.40± 27.46). Based on receiver operator characteristic curve analysis, serum AFP still surpassed serum CLU in diagnostic sensitivity (77.3% vs. 70.5%), specificity (100% vs. 90%), and positive and negative predictive values (100% vs. 86.1% and 83.3% vs. 77.6% respectively). The use of a combined parallel approach improved the diagnostic sensitivity (95.5%) and negative predictive value (95.7%) over the single use of AFP.Conclusions: Although the diagnostic performance of serum AFP outperformed that of serum CLU, their combined parallel approach improved the sensitivity which is required in screening high risk populations such as CHC patients. KEYWORDS Clusterin; Alpha fetoprotein; Tumor marker; Hepatitis C virus related liver cirrhosis; Hepatocellular carcinom

Azotobacter genomes: the genome of Azotobacter chroococcum NCIMB 8003 (ATCC 4412)

The genome of the soil-dwelling heterotrophic N2-fixing Gram-negative bacterium Azotobacter chroococcum NCIMB 8003 (ATCC 4412) (Ac-8003) has been determined. It consists of 7 circular replicons totalling 5,192,291 bp comprising a circular chromosome of 4,591,803 bp and six plasmids pAcX50a, b, c, d, e, f of 10,435 bp, 13,852, 62,783, 69,713, 132,724, and 311,724 bp respectively. The chromosome has a G+C content of 66.27% and the six plasmids have G+C contents of 58.1, 55.3, 56.7, 59.2, 61.9, and 62.6% respectively. The methylome has also been determined and 5 methylation motifs have been identified. The genome also contains a very high number of transposase/inactivated transposase genes from at least 12 of the 17 recognised insertion sequence families. The Ac-8003 genome has been compared with that of Azotobacter vinelandii ATCC BAA-1303 (Av-DJ), a derivative of strain O, the only other member of the Azotobacteraceae determined so far which has a single chromosome of 5,365,318 bp and no plasmids. The chromosomes show significant stretches of synteny throughout but also reveal a history of many deletion/insertion events. The Ac-8003 genome encodes 4628 predicted protein-encoding genes of which 568 (12.2%) are plasmid borne. 3048 (65%) of these show > 85% identity to the 5050 protein-encoding genes identified in Av-DJ, and of these 99 are plasmid-borne. The core biosynthetic and metabolic pathways and macromolecular architectures and machineries of these organisms appear largely conserved including genes for CO-dehydrogenase, formate dehydrogenase and a soluble NiFe-hydrogenase. The genetic bases for many of the detailed phenotypic differences reported for these organisms have also been identified. Also many other potential phenotypic differences have been uncovered. Properties endowed by the plasmids are described including the presence of an entire aerobic corrin synthesis pathway in pAcX50f and the presence of genes for retro-conjugation in pAcX50c. All these findings are related to the potentially different environmental niches from which these organisms were isolated and to emerging theories about how microbes contribute to their communities