Loss of Chromosome 18 in Neuroendocrine Tumors of the Midgut Abstract #730

Introduction: The genetic alterations in neuroendocrine tumors (NET) of the midgut, in particular of the appendix (aNET), are poorly characterized. The most frequent chromosomal aberration in ileal NET (iNET) is the loss of one chromosome 18. The relevance of this alteration is unclear.
Aim(s): We investigated the status of chromosome 18 and the expression of chromosome 18-related tumor suppressor proteins in aNET in comparison to iNET, in order to identify factors that could explain the different clinical behavior.
Materials and methods: The loss of chromosome 18 was examined using fluorescence in situ hybridization in 53 primary aNET and 77 primary iNET. The expression of tumor suppressor proteins Smad2, Smad4, Maspin and DCC was assessed by immunohistochemistry. Tumor suppressors were also stained in normal endocrine cells by immunofluorescence double labelling.
Conference: 10th Annual ENETS Conference (2013)
Category: Basic Science - Genetics, epigenetics, miRNAs
Presenting Author: MD Tobias Henopp
Keywords: chr18

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