title: Analysis of CUL-5 expression in breast epithelial cells, breast cancer cell lines, normal tissues and tumor tissues.
abstract: BACKGROUND
  The chromosomal location of CUL-5 (11q 22-23) is associated with LOH in breast cancer, suggesting that CUL-5 may be a tumor suppressor. The purpose of this research was to determine if there is differential expression of CUL-5 in breast epithelial cells versus breast cancer cell lines, and normal human tissues versus human tumors. The expression of CUL-5 in breast epithelial cells (HMEC, MCF-10A), and breast cancer cells (MCF-7, MDA-MB-231) was examined using RT-PCR, Northern blot analysis, and Western blot analysis. The expression of mRNA for other CUL family members (CUL-1, -2, -3, -4A, and -4B) in these cells was evaluated by RT-PCR. A normal human tissue expression array and a cancer profiling array were used to examine CUL-5 expression in normal human tissues and matched normal tissues versus tumor tissues, respectively.
  
  
  RESULTS
  CUL-5 is expressed at the mRNA and protein levels by breast epithelial cells (HMEC, MCF-10A) and breast cancer cells (MCF-7, MDA-MB-231). These cells also express mRNA for other CUL family members. The normal human tissue expression array revealed that CUL-5 is widely expressed. The cancer profiling array revealed that 82% (41/50) of the breast cancers demonstrated a decrease in CUL-5 expression versus the matched normal tissue. For the 50 cases of matched breast tissue there was a statistically significant approximately 2.2 fold decreased expression of CUL-5 in tumor tissue versus normal tissue (P < 0.0001).
  
  
  CONCLUSIONS
  The data demonstrate no apparent decrease in CUL-5 expression in the breast cancer cell lines (MCF-7, MDA-MB-231) versus the breast epithelial cells (HMEC, MCF-10A). The decrease in CUL-5 expression in breast tumor tissue versus matched normal tissue supports the hypothesis that decreased expression of CUL-5 may play a role in breast tumorigenesis.
authors.affiliation: Department of Pharmacology, Midwestern University, Chicago College of Osteopathic Medicine, 555 31st Street, Downers Grove, IL 60515, USA. mfayxx@midwestern.edu
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Fay
authors.forename: Kenneth A
authors.initials: KA
authors.lastname: Longo
authors.forename: George A
authors.initials: GA
authors.lastname: Karathanasis
authors.forename: David M
authors.initials: DM
authors.lastname: Shope
authors.forename: Craig J
authors.initials: CJ
authors.lastname: Mandernach
authors.forename: Jason R
authors.initials: JR
authors.lastname: Leong
authors.forename: Alfred
authors.initials: A
authors.lastname: Hicks
authors.forename: Kenneth
authors.initials: K
authors.lastname: Pherson
authors.forename: Amyna
authors.initials: A
authors.lastname: Husain
mesh_terms: D001940:Breast / Q000166:cytology* / Q000473:pathology*; D001943:Breast Neoplasms / Q000235:genetics* / Q000473:pathology; D045744:Cell Line, Tumor; D044842:Cullin Proteins / Q000096:biosynthesis*; D004847:Epithelial Cells / Q000737:chemistry* / Q000378:metabolism* / Q000473:pathology; D020869:Gene Expression Profiling / Q000379:methods; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics; D006801:Humans; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods; D009928:Organ Specificity / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis; D012334:RNA, Neoplasm / Q000096:biosynthesis; D017483:Receptors, Vasopressin / Q000096:biosynthesis*
chemical_list: C496871:CUL5 protein, human; D044842:Cullin Proteins; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D017483:Receptors, Vasopressin