@article{vonRahdenKircherLazariotouetal.2011,
  author    = {von Rahden, Burkhard H.A. and Kircher, Stefan and Lazariotou, Maria and Reiber, Christoph and Stuermer, Luisa and Otto, Christoph and Germer, Christoph T. and Grimm, Martin},
  title     = {LgR5 expression and cancer stem cell hypothesis: clue to define the true origin of esophageal adenocarcinomas with and without Barrett's Esophagus?},
  series = {Journal of Experimental \& Clinical Cancer Research},
  volume    = {30},
  journal   = {Journal of Experimental \& Clinical Cancer Research},
  number    = {23},
  doi       = {10.1186/1756-9966-30-23},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-137783},
  year      = {2011},
  abstract  = {Background Investigation of the expression of an intestinal stem cell marker in esophageal adenocarcinomas (EAC) with and without Barrett's Esophagus (BE), with respect to a cancer stem cell (CSC) hypothesis. Materials and methods Expression of a putative intestinal stem cell marker LgR5 was analyzed in esophageal cancer specimen (n = 70: 41 EAC with BE, 19 EAC without BE, and n = 10 esophageal squamous-cell carcinomas, ESCC) and in the adenocarcinoma cell line OE-33. Ki-67 and Cdx-2 were co-labelled with LgR5 in double staining experiments. Immunhistochemical expression results were confirmed by RT-PCR and correlated with tumor stage and five-year survival rates. Results LgR5was found expressed in 35 of 41 (85\%) EAC with BE and in 16 of 19 (81\%) EAC without BE. By contrast, LgR5 was not found to be expressed in ESCC. Quantification of immunolabeling showed 15\% LgR5+ cells in EAC with BE, 32\% LgR5+ cells in adjacent BE and 13\% in EAC without BE. Immunofluorescence double staining experiments with LgR5 and Ki-67 revealed a subpopulation (~5\%) of proliferating LgR+/Ki-67+ cells. On mRNA-level, expression of LgR5 was higher in BE in comparison to EAC (p = 0.0159). High levels of LgR5 expression in BE associated EAC were associated with poorer survival in univariate analysis. Conclusion The stem cell marker LgR5 is expressed in EAC, irrespective of association with BE, and appears to have negative impact on survival. The subset of proliferating LgR5+ cells (<5\%) might resemble rapidly cycling CSCs, which needs to be substantiated in further investigations.},
  language  = {en}
}
@article{KimGrimmigGrimmetal.2013,
  author    = {Kim, Mia and Grimmig, Tanja and Grimm, Martin and Lazariotou, Maria and Meier, Eva and Rosenwald, Andreas and Tsaur, Igor and Blaheta, Roman and Heemann, Uwe and Germer, Christoph-Thomas and Waaga-Gasser, Ana Maria and Gasser, Martin},
  title     = {Expression of Foxp3 in Colorectal Cancer but Not in Treg Cells Correlates with Disease Progression in Patients with Colorectal Cancer},
  series = {PLoS ONE},
  volume    = {8},
  journal   = {PLoS ONE},
  number    = {1},
  doi       = {10.1371/journal.pone.0053630},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-130340},
  pages     = {e53630},
  year      = {2013},
  abstract  = {Background Measles virus (MV) causes T cell suppression by interference with phosphatidylinositol-3-kinase (PI3K) activation. We previously found that this interference affected the activity of splice regulatory proteins and a T cell inhibitory protein isoform was produced from an alternatively spliced pre-mRNA. Hypothesis Differentially regulated and alternatively splice variant transcripts accumulating in response to PI3K abrogation in T cells potentially encode proteins involved in T cell silencing. Methods To test this hypothesis at the cellular level, we performed a Human Exon 1.0 ST Array on RNAs isolated from T cells stimulated only or stimulated after PI3K inhibition. We developed a simple algorithm based on a splicing index to detect genes that undergo alternative splicing (AS) or are differentially regulated (RG) upon T cell suppression. Results Applying our algorithm to the data, 9\% of the genes were assigned as AS, while only 3\% were attributed to RG. Though there are overlaps, AS and RG genes differed with regard to functional regulation, and were found to be enriched in different functional groups. AS genes targeted extracellular matrix (ECM)-receptor interaction and focal adhesion pathways, while RG genes were mainly enriched in cytokine-receptor interaction and Jak-STAT. When combined, AS/RG dependent alterations targeted pathways essential for T cell receptor signaling, cytoskeletal dynamics and cell cycle entry. Conclusions PI3K abrogation interferes with key T cell activation processes through both differential expression and alternative splicing, which together actively contribute to T cell suppression.},
  language  = {en}
}