title: NUCKS overexpression in breast cancer.
abstract: BACKGROUND
  NUCKS (Nuclear, Casein Kinase and Cyclin-dependent Kinase Substrate) is a nuclear, DNA-binding and highly phosphorylated protein. A number of reports show that NUCKS is highly expressed on the level of mRNA in several human cancers, including breast cancer. In this work, NUCKS expression on both RNA and protein levels was studied in breast tissue biopsies consisted of invasive carcinomas, intraductal proliferative lesions, benign epithelial proliferations and fibroadenomas, as well as in primary cultures derived from the above biopsies. Specifically, in order to evaluate the level of NUCKS protein in correlation with the histopathological features of breast disease, immunohistochemistry was employed on paraffin sections of breast biopsies of the above types. In addition, NUCKS expression was studied by means of Reverse Transcription PCR (RT-PCR), real-time PCR (qRT-PCR) and Western immunoblot analyses in the primary cell cultures developed from the same biopsies.
  
  
  RESULTS
  The immunohistochemical Results showed intense NUCKS staining mostly in grade I and II breast carcinomas compared to normal tissues. Furthermore, NUCKS was moderate expressed in benign epithelial proliferations, such as adenosis and sclerosing adenosis, and highly expressed in intraductal lesions, specifically in ductal carcinomas in situ (DCIS). It is worth noting that all the fibroadenoma tissues examined were negative for NUCKS staining. RT-PCR and qRT-PCR showed an increase of NUCKS expression in cells derived from primary cultures of proliferative lesions and cancerous tissues compared to the ones derived from normal breast tissues and fibroadenomas. This increase was also confirmed by Western immunoblot analysis. Although NUCKS is a cell cycle related protein, its expression does not correlate with Ki67 expression, neither in tissue sections nor in primary cell cultures.
  
  
  CONCLUSIONS
  The results show overexpression of the NUCKS protein in a number of non malignant breast lesions and cancerous tissues. In particular, the NUCKS overexpression in ADH and DCIS indicates a significant role of this protein in neoplastic progression.
authors: Department of Genetics and Biotechnology, Faculty of Biology, University of Athens, Panepistimioupoli, 15701 Ilissia, Greece. ydrosos@biol.uoa.gr
authors: Yiannis
authors: Y
authors: Drosos
authors: Mirsini
authors: M
authors: Kouloukoussa
authors: Anne Carine
authors: AC
authors: Østvold
authors: Kirsten
authors: K
authors: Grundt
authors: Nikos
authors: N
authors: Goutas
authors: Dimitrios
authors: D
authors: Vlachodimitropoulos
authors: Sophia
authors: S
authors: Havaki
authors: Panagoula
authors: P
authors: Kollia
authors: Christos
authors: C
authors: Kittas
authors: Evangelos
authors: E
authors: Marinos
authors: Vassiliki
authors: V
authors: Aleporou-Marinou