One Step Nucleic Acid Amplification (OSNA) - a new method for lymph node staging in colorectal carcinomas

<p>Abstract</p> <p>Background</p> <p>Accurate histopathological evaluation of resected lymph nodes (LN) is essential for the reliable staging of colorectal carcinomas (CRC). With conventional sectioning and staining techniques usually only parts of the LN are examined which might lead to incorrect tumor staging. A molecular method called OSNA (One Step Nucleic Acid Amplification) may be suitable to determine the metastatic status of the complete LN and therefore improve staging.</p> <p>Methods</p> <p>OSNA is based on a short homogenisation step and subsequent automated amplification of cytokeratin 19 (CK19) mRNA directly from the sample lysate, with result available in 30-40 minutes. In this study 184 frozen LN from 184 patients with CRC were investigated by both OSNA and histology (Haematoxylin & Eosin staining and CK19 immunohistochemistry), with half of the LN used for each method. Samples with discordant results were further analysed by RT-PCR for CK19 and carcinoembryonic antigen (CEA).</p> <p>Results</p> <p>The concordance rate between histology and OSNA was 95.7%. Three LN were histology+/OSNA- and 5 LN histology-/OSNA+. RT-PCR supported the OSNA result in 3 discordant cases, suggesting that metastases were exclusively located in either the tissue analysed by OSNA or the tissue used for histology. If these samples were excluded the concordance was 97.2%, the sensitivity 94.9%, and the specificity 97.9%. Three patients (3%) staged as UICC I or II by routine histopathology were upstaged as LN positive by OSNA. One of these patients developed distant metastases (DMS) during follow up.</p> <p>Conclusion</p> <p>OSNA is a new and reliable method for molecular staging of lymphatic metastases in CRC and enables the examination of whole LN. It can be applied as a rapid diagnostic tool to estimate tumour involvement in LN during the staging of CRC.</p

Spezifität der Inhibition von Cathepsin L-ähnlichen Cysteinproteasen durch ihre Propeptide

Die Cathepsine H, K, L und S sind Mitglieder der Papainfamilie innerhalb der Cysteinproteasen. Ihr Wirkungsbereich reicht vom unspezifischen proteolytischen Abbau bis zur Beteiligung in hochspezialisierten Kaskaden. Sie haben Bedeutung bei der Immunantwort, bei der Tumorausbreitung und bei Autoimmunerkrankungen. Die Enzyme werden als unwirksame Vorläufermoleküle synthetisiert, bei denen das aktive Zentrum durch die N- terminale Prosequenz blockiert ist. Diese Prosequenz hemmt den Substratzugang am aktiven Zentrum auch als isoliertes Propeptid mit höherer Affinität als synthetische Inhibitoren. Unter dem Gesichtspunkt der Spezifität weisen die untersuchten Propeptide Unterschiede auf, die mit der evolutionären Verwandtschaft übereinstimmen: Die propeptide K und S besitzen Gruppenspezifität, das Propeptid L dagegen wirkt selektiv auf sein Mutterenzym. Das medizinische Interesse liegt darin, dass von inhibitorischen Propeptiden abgeleitete pharmakologische Wirkstoffe denkbar und z.T. schon konzipiert sind

Quantitative Estimation and Chemical Coding of Spiny Type I Neurons in Human Intestines

Previous studies have shown that most human myenteric neurons co-staining for vasoactive intestinal peptide (VIP), neuronal nitric oxide synthase (nNOS) and neurofilaments (NF) display the morphology of spiny type I neurons displaying a descending projection pattern. Here, we estimated the proportions of spiny neurons in human intestines, the amount of congruence of VIP/nNOS-immunoreactive with spiny neurons and whether galanin (GAL) is co-localized with VIP. Three sets of colchicine-pretreated and fixed whole mounts of 21 patients or body donors (median age 65 years; 10 female, 11 male) were stained for VIP, nNOS and NF, for VIP, nNOS and the human neuronal protein Hu C/D (HU) as well as for VIP, nNOS and GAL. The majority of VIP/nNOS-co-reactive neurons were spiny neurons (79/80% in small/large intestine, respectively) and the majority of spiny neurons costained for VIP and nNOS (82/69%). Neurons co-immunoreactive for VIP/nNOS/HU amounted to 7 and 4%, respectively. GAL/VIP-co-immunoreactivity was demonstrated in 69 and 27% of spiny neurons, respectively. We conclude that the number of neurons displaying co-reactivity for VIP and nNOS is a quantitative indicator of spiny neurons in both small and large intestine and that the proportion of spiny neurons is about 7% in small and 4% in large intestines. Since nerve fibres co-staining for NF/VIP/nNOS were found mainly in the circular muscle layer but not the surrounding perikarya of spiny neurons, we suggest that they may represent inhibitory motor neurons rather than descending interneurons

Nicotinic Acetylcholine Receptors in Head and Neck Cancer and Their Correlation to Tumor Site and Progression

Background: Nicotine contributes to tumorigenesis through stimulation of nicotinic acetylcholine receptors (nAChRs) in head and neck squamous cell carcinoma (SCC). Although many factors have been found to be involved in the pathogenesis of head and neck cancer, the effect of nAChRs is still unclear. The study provides information on different subtypes in SCC and normal mucosa (NM) and their clinicopathological correlation to tumor progression. Methods: SCC (n = 34) of oropharynx, hypopharynx, larynx and corresponding NM (n = 38) were analyzed by quantitative real-time polymerase chain reaction, immunoblotting and immunohistochemistry and correlated to tumor grading and Union for International Cancer Control (UICC) stage. Results: nAChR subtypes α1, α3, α5 and α7 were found in NM and SCC of the upper aerodigestive tract with high rates of α1 and α5 in SCC. An overexpression of α1 was found in laryngeal and hypopharyngeal SCC, while α3 and α7 subunits were downregulated. The expression of α1 and α5 subunits increased with tumor progression. Conclusion: The nAChR subunit pattern shows a difference between NM and SCC and changes in the process of tumor progression. Therefore, it is conceivable that it contributes to tumorigenesis. The findings provide a basis for further studies in prognostic assessment and identifying carcinogenic changes from NM to SCC

Microsomal triglyceride transfer protein polymorphism (-493G/T) is associated with hepatic steatosis in patients with chronic hepatitis C

BACKGROUND: Hepatic steatosis may promote progression of chronic hepatitis C (CHC). Microsomal triglyceride transfer protein (MTP) is required for assembly and secretion of ApoB lipoprotein and is implicated in hepatitis C virus (HCV)-related steatosis. The MTP -493G/T polymorphism may promote liver fat accumulation, but its role in HCV-related steatosis is still unclear. METHODS: Two hundred ninety-eight CHC patients were studied and genotyped for MTP -493G/T variants. Hepatic MTP mRNA expression and activity were determined in a subgroup. RESULTS: Patients with grades 2/3 steatosis were older, had a higher body mass index (BMI), more advanced fibrosis and lower MTP mRNA expression and carried more often HCV genotype 3 and the MTP T allele. Age, BMI, HCV-3 and MTP T allele [odds ratio (OR) 2.05; 95% confidence interval (CI) 1.2-3.53; P=0.009] were independent risk factors for steatosis grades 2/3, and in HCV genotype non-3 patients, the MTP T allele was the strongest predictor for steatosis grade 2/3 (OR 2.17; 95% CI 1.22-3.86; P=0.008). Moreover, TT carriers had higher high-density lipoprotein (65.6+/-14.6 vs 56.1+/-16.2 mg/dl; P=0.003) and apolipoprotein AI (1.80+/-0.3 vs 1.60+/-0.3 g/L; P=0.005) levels than G allele carriers. CONCLUSIONS: Chronic hepatitis C patients with the MTP -493T allele reveal higher grades of steatosis, indicating a relevant contribution to liver fat accumulation, particularly in HCV non-3 patients