Biologische und funktionale Charakterisierung von Tumoren im Gastrointestinaltrakt durch genomweite Genexpressions-Analyse und Identifizierung von potentiellen Tumormarkern

Die Untersuchungen in der vorliegenden Arbeit umfassen mit dem Magenkarzinom, dem kolorektalen Karzinom und dem neuroendokrinen Tumor drei verschiedene Entitäten, die zwar alle im Gastrointestinaltrakt lokalisiert sind, deren Genese und Progression aber unterschiedlich abläuft. 1. Etablierung und Evaluierung eines Serum-Protein-Biochips, der durch die quantitative Bestimmung von neun Biomarkern im Serum von Patienten eine frühestmögliche Diagnose eines vorhandenen kolorektalen Karzinoms ermöglicht. Dazu wurden insgesamt 474 Seren mit der Evidence Investigator™ Biochip Technologie der Firma Randox getestet. 2. Etablierung und Charakterisierung einer gewebebasierten Signatur zur Bestimmung der Lokalisation des Primärtumors bei neuroendokrinen Tumoren (NETs) mit CUP-Syndrom (cancer of unknown primary). Anhand des Expressionslevels dreier Gene (CD302, PPWD1 und ABHD14B) konnte der Entstehungsort des Primärtumors bei knapp 100 NETs mit einer Spezifität von 67-98% bestimmt werden. Der Drei-Gen-Klassifikators wurde patentiert. 3. Erstellung und Auswertung von DNA Aberrations-Profilen sowie Darstellung der fehlregulierten Signalwege an 29 Magenkarzinomen, anhand derer gezeigt werden konnte, dass die Anzahl der individuellen DNA-Aberrationen mit der Überlebenswahrscheinlichkeit der Patienten korreliert und dass es Subgruppen beim Magenkarzinom gibt, die unabhängig von der TNM- und der Laurén-Klassifikation auf verschiedene Chemotherapien ansprechen. Zusammenfassend zeigen die Ergebnisse der drei untersuchten Tumorentitäten des Gastrointestinaltraktes, dass die Vernetzung von globalen, adaptierten Verfahren, wie der Genenexpressions-Analyse mit funktionellen Untersuchungen einzelner Gene, es erlauben biologische und klinische Fragestellungen translational zu untersuchen, um so einerseits molekulargenetische Grundlagen der malignen Progression von Tumoren weiter aufzuklären und andererseits zur Optimierung von Diagnose und individualisierter Therapie beitragen zu können

Derivative chromosome 1 and GLUT1 deficiency syndrome in a sibling pair

<p>Abstract</p> <p>Background</p> <p>Genomic imbalances constitute a major cause of congenital and developmental abnormalities. GLUT1 deficiency syndrome is caused by various de novo mutations in the facilitated human glucose transporter 1 gene (1p34.2) and patients with this syndrome have been diagnosed with hypoglycorrhachia, mental and developmental delay, microcephaly and seizures. Furthermore, 1q terminal deletions have been submitted in the recent reports and the absence of corpus callosum has been related to the deletion between <it>C1orf100 </it>and <it>C1orf121 </it>in 1q44.</p> <p>Results</p> <p>This study reports on a sibling pair with developmental delay, mental retardation, microcephaly, hypotonia, epilepsy, facial dysmorphism, ataxia and impaired speech. Chromosome analysis revealed a derivative chromosome 1 in both patients. FISH and MCB analysis showed two interstitial deletions at 1p34.2 and 1q44. SNP array and array-CGH analysis also determined the sizes of deletions detailed. The deleted region on 1p34.2 encompasses 33 genes, among which is <it>GLUT1 </it>gene (<it>SLC2A1</it>). However, the deleted region on 1q44 includes 59 genes and distal-proximal breakpoints were located in the ZNF672 gene and SMYD3 gene, respectively.</p> <p>Conclusion</p> <p>Haploinsufficiency of <it>GLUT1 </it>leads to GLUT1 deficiency syndrome, consistent with the phenotype in patients of this study. Conversely, in the deleted region on 1q44, none of the genes are related to findings in these patients. Additionally, the results confirm previous reports on that corpus callosal development may depend on the critical gene(s) lying in 1q44 proximal to the <it>SMYD3 </it>gene.</p

A novel multiplex-protein array for serum diagnostics of colon cancer: a case–control study

Abstract Background More than 1.2 million new cases of colorectal cancer are reported each year worldwide. Despite actual screening programs, about 50% of the patients are diagnosed at advanced tumor stages presenting poor prognosis. Innovative screening tools could aid the detection at early stages and allow curative treatment interventions. Methods A nine target multiplex serum protein biochip was generated and evaluated using a training- and validation-set of 317 highly standardized, liquid nitrogen preserved serum samples comprising controls, adenomas, and colon cancers. Results Serum levels of CEA, IL-8, VEGF, S100A11, MCSF, C3adesArg, CD26, and CRP showed significant differences between cases and controls. The largest areas under the receiver operating characteristics curve were observed for CEA, IL-8, and CRP. At threshold levels yielding 90% specificity, sensitivities for CEA, IL-8 and CRP were 26%, 22%, and 17%, respectively. The most promising marker combinations were CEA + IL-8 reaching 37% sensitivity at 83% specificity and CEA + CRP with 35% sensitivity at 81% specificity. In an independent validation set CEA + IL-8 reached 47% sensitivity at 86% specificity while CEA + CRP obtained 39% sensitivity at 86% specificity. Early carcinomas were detected with 33% sensitivity for CEA + IL-8 and 28% for CEA + CRP. Conclusions Apart from CEA, IL-8, and CRP, the screening value of additional blood markers and the potential advantage of combining serum biochip testing with fecal occult blood testing needs to be studied. Multiplex biochip array technology utilizing serum samples offers an innovative approach to colorectal cancer screening.</p

Disruption of ALX1 Causes Extreme Microphthalmia and Severe Facial Clefting: Expanding the Spectrum of Autosomal-Recessive ALX-Related Frontonasal Dysplasia

We present an autosomal-recessive frontonasal dysplasia (FND) characterized by bilateral extreme microphthalmia, bilateral oblique facial cleft, complete cleft palate, hypertelorism, wide nasal bridge with hypoplasia of the ala nasi, and low-set, posteriorly rotated ears in two distinct families. Using Affymetrix 250K SNP array genotyping and homozygosity mapping, we mapped this clinical entity to chromosome 12q21. In one of the families, three siblings were affected, and CNV analysis of the critical region showed a homozygous 3.7 Mb deletion containing the ALX1 (CART1) gene, which encodes the aristaless-like homeobox 1 transcription factor. In the second family we identified a homozygous donor-splice-site mutation (c.531+1G > A) in the ALX1 gene, providing evidence that complete loss of function of ALX1 protein causes severe disruption of early craniofacial development. Unlike loss of its murine ortholog, loss of human ALX1 does not result in neural-tube defects; however, it does severely affect the orchestrated fusion between frontonasal, nasomedial, nasolateral, and maxillary processes during early-stage embryogenesis. This study further expands the spectrum of the recently recognized autosomal-recessive ALX-related FND phenotype in humans