title: Paralemmin-1 is over-expressed in estrogen-receptor positive breast cancers.
abstract: BACKGROUND
  Paralemmin-1 is a phosphoprotein lipid-anchored to the cytoplasmic face of membranes where it functions in membrane dynamics, maintenance of cell shape, and process formation. Expression of paralemmin-1 and its major splice variant (Δ exon 8) as well as the extent of posttranslational modifications are tissue- and development-specific. Paralemmin-1 expression in normal breast and breast cancer tissue has not been described previously.
  
  
  RESULTS
  Paralemmin-1 mRNA and protein expression was evaluated in ten breast cell lines, 26 primary tumors, and 10 reduction mammoplasty (RM) tissues using real time RT-PCR. Paralemmin-1 splice variants were assessed in tumor and RM tissues using a series of primers and RT-PCR. Paralemmin-1 protein expression was examined in cell lines using Western Blots and in 31 ductal carcinomas in situ, 65 infiltrating ductal carcinomas, and 40 RM tissues using immunohistochemistry. Paralemmin-1 mRNA levels were higher in breast cancers than in RM tissue and estrogen receptor (ER)-positive tumors had higher transcript levels than ER-negative tumors. The Δ exon 8 splice variant was detected more frequently in tumor than in RM tissues. Protein expression was consistent with mRNA results showing higher paralemmin-1 expression in ER-positive tumors.
  
  
  CONCLUSIONS
  The differential expression of paralemmin-1 in a subset of breast cancers suggests the existence of variation in membrane dynamics that may be exploited to improve diagnosis or provide a therapeutic target.
authors.affiliation: University of Massachusetts, 637 North Pleasant Street, Amherst, MA 01003-9298, USA. karcaro@vasci.umass.edu.
authors.forename: Casey M
authors.initials: CM
authors.lastname: Turk
authors.forename: Katerina D
authors.initials: KD
authors.lastname: Fagan-Solis
authors.forename: Kristin E
authors.initials: KE
authors.lastname: Williams
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Gozgit
authors.forename: Sallie
authors.initials: S
authors.lastname: Smith-Schneider
authors.forename: Sharon A
authors.initials: SA
authors.lastname: Marconi
authors.forename: Christopher N
authors.initials: CN
authors.lastname: Otis
authors.forename: Giovanna M
authors.initials: GM
authors.lastname: Crisi
authors.forename: Douglas L
authors.initials: DL
authors.lastname: Anderton
authors.forename: Manfred W
authors.initials: MW
authors.lastname: Kilimann
authors.forename: Kathleen F
authors.initials: KF
authors.lastname: Arcaro