@article{DaskalowBoisguerinJandrigetal.2010,
  author    = {Daskalow, Katjana and Boisguerin, Prisca and Jandrig, Burkhard and van Landeghem, Frank K. H. and Volkmer, Rudolf and Micheel, Burkhard and Schenk, J{\"o}rg A.},
  title     = {Generation of an antibody against the protein phosphatase 1 inhibitor KEPI and characterization of the epitope},
  issn      = {0250-7005},
  year      = {2010},
  abstract  = {A monoclonal antibody against the potential tumor suppressor kinase-enhanced protein phosphatase 1 (PP1) inhibitor KEPI (PPP1R14C) was generated and characterized. Human KEPI was expressed in Escherichia coli and used to immunize Balb/c mice. Using hybridoma technology, one clone, G18AF8, was isolated producing antibodies which bound specifically to the KEPI protein in ELISA, immunoblotting and flow cytometry. The antibody was also successfully applied to stain KEPI protein in paraffin sections of human brain. The epitope was mapped using peptide array technology and confirmed as GARVFFQSPR. This corresponds to the N-terminal region of KEPI. Amino acid substitution analysis revealed that two residues, F and Q, are essential for binding. Affinity of binding was determined by competitive ELISA as 1 mu M. In Western blot assays testing G18AF8 antibody on brain samples of several species, reactivity with hamster, rat and chicken samples was found, suggesting a broad homology of this KEPI epitope in vertebrates. This antibody could be used in expression studies at the protein level e.g. in tumor tissues.},
  language  = {en}
}
@phdthesis{Daskalow2008,
  author    = {Daskalow, Katjana},
  title     = {Die Bedeutung des Hypoxie-induzierbaren Transkriptionsfaktors HIF-1a und der Glykolyse f{\"u}r die Entstehung und Progression des hepatozellul{\"a}ren Karzinoms},
  address   = {Potsdam},
  pages     = {110 S.},
  year      = {2008},
  language  = {de}
}
@article{SchlagOsterzielOezceliketal.2008,
  author    = {Schlag, Peter M. and Osterziel, Karl Joseph and {\"O}zcelik, Cemil and Scherneck, Siegfried and Wenzel, Katrin and Daskalow, Katjana and Herse, Florian and Seitz, Susanne and Zacharias, Ute and Schenk, J{\"o}rg A. and Schulz, Herbert and H{\"u}bner, Norbert and Micheel, Burkhard},
  title     = {The protein phosphatase 1 inhibitor KEPI is down regulated in breast cancer cell lines and tissues and involved in the regulation of the tumour suppressor EGR1 via the MEK-ERK pathway},
  year      = {2008},
  abstract  = {KEPI is a protein kinase C-potentiated inhibitory protein for type 1 Ser/Thr protein phosphatases. We found no or reduced expression of KEPI in breast cancer cell lines, breast tumors and metastases in comparison to normal breast cell lines and tissues, respectively. KEPI protein expression and ubiquitous localization was detected with a newly generated antibody. Ectopic KEPI expression in MCF7 breast cancer cells induced differential expression of 95 genes, including the up-regulation of the tumor suppressors EGR1 (early growth response 1) and PTEN (phosphatase and tensin homolog), which is regulated by EGR1. We further show that the up-regulation of EGR1 in MCF7/KEPI cells is mediated by MEK-ERK signaling. The inhibition of this pathway by the MEK inhibitor UO126 led to a strong decrease in EGR1 expression in MCF7/KEPI cells. These results reveal a novel role for KEPI in the regulation of the tumor suppressor gene EGR1 via activation of the MEK-ERK MAPK pathway.},
  language  = {en}
}