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Title: Plasma membrane calcium-ATPase 2 and 4 in human breast cancer cell lines

Abstract

There is evidence to suggest that plasma membrane Ca{sup 2+}-ATPase (PMCA) isoforms are important mediators sssof mammary gland physiology. PMCA2 in particular is upregulated extensively during lactation. Expression of other isoforms such as PMCA4 may influence mammary gland epithelial cell proliferation and aberrant regulation of PMCA isoform expression may lead or contribute to mammary gland pathophysiology in the form of breast cancers. To explore whether PMCA2 and PMCA4 expression may be deregulated in breast cancer, we compared mRNA expression of these PMCA isoforms in tumorigenic and non-tumorigenic human breast epithelial cell lines using real time RT-PCR. PMCA2 mRNA has a higher level of expression in some breast cancer cell lines and is overexpressed more than 100-fold in ZR-75-1 cells, compared to non-tumorigenic 184B5 cells. Although differences in PMCA4 mRNA levels were observed between breast cell lines, they were not of the magnitude observed for PMCA2. We conclude that PMCA2 mRNA can be highly overexpressed in some breast cancer cells. The significance of PMCA2 overexpression on tumorigenicity and its possible correlation with other properties such as invasiveness requires further study.

Authors:
 [1];  [1];  [2]
  1. School of Pharmacy, University of Queensland, Brisbane, Qld 4072 (Australia)
  2. School of Pharmacy, University of Queensland, Brisbane, Qld 4072 (Australia). E-mail: G.Monteith@pharmacy.uq.edu.au
Publication Date:
OSTI Identifier:
20713451
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biochemical and Biophysical Research Communications; Journal Volume: 337; Journal Issue: 3; Other Information: DOI: 10.1016/j.bbrc.2005.09.119; PII: S0006-291X(05)02152-2; Copyright (c) 2005 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; CALCIUM; CALCIUM IONS; CARCINOMAS; CELL PROLIFERATION; GENE REGULATION; LACTATION; MAMMARY GLANDS; MEMBRANES; PHYSIOLOGY; POLYMERASE CHAIN REACTION; TRANSCRIPTION

Citation Formats

Lee, Won Jae, Roberts-Thomson, Sarah J., and Monteith, Gregory R.. Plasma membrane calcium-ATPase 2 and 4 in human breast cancer cell lines. United States: N. p., 2005. Web. doi:10.1016/j.bbrc.2005.09.119.
Lee, Won Jae, Roberts-Thomson, Sarah J., & Monteith, Gregory R.. Plasma membrane calcium-ATPase 2 and 4 in human breast cancer cell lines. United States. doi:10.1016/j.bbrc.2005.09.119.
Lee, Won Jae, Roberts-Thomson, Sarah J., and Monteith, Gregory R.. Fri . "Plasma membrane calcium-ATPase 2 and 4 in human breast cancer cell lines". United States. doi:10.1016/j.bbrc.2005.09.119.
@article{osti_20713451,
title = {Plasma membrane calcium-ATPase 2 and 4 in human breast cancer cell lines},
author = {Lee, Won Jae and Roberts-Thomson, Sarah J. and Monteith, Gregory R.},
abstractNote = {There is evidence to suggest that plasma membrane Ca{sup 2+}-ATPase (PMCA) isoforms are important mediators sssof mammary gland physiology. PMCA2 in particular is upregulated extensively during lactation. Expression of other isoforms such as PMCA4 may influence mammary gland epithelial cell proliferation and aberrant regulation of PMCA isoform expression may lead or contribute to mammary gland pathophysiology in the form of breast cancers. To explore whether PMCA2 and PMCA4 expression may be deregulated in breast cancer, we compared mRNA expression of these PMCA isoforms in tumorigenic and non-tumorigenic human breast epithelial cell lines using real time RT-PCR. PMCA2 mRNA has a higher level of expression in some breast cancer cell lines and is overexpressed more than 100-fold in ZR-75-1 cells, compared to non-tumorigenic 184B5 cells. Although differences in PMCA4 mRNA levels were observed between breast cell lines, they were not of the magnitude observed for PMCA2. We conclude that PMCA2 mRNA can be highly overexpressed in some breast cancer cells. The significance of PMCA2 overexpression on tumorigenicity and its possible correlation with other properties such as invasiveness requires further study.},
doi = {10.1016/j.bbrc.2005.09.119},
journal = {Biochemical and Biophysical Research Communications},
number = 3,
volume = 337,
place = {United States},
year = {Fri Nov 25 00:00:00 EST 2005},
month = {Fri Nov 25 00:00:00 EST 2005}
}
  • During metastasis, it is believed that tumor cells destroy the basement membrane (BM) of blood vessels in order to disseminate through the circulatory system. By radioactively labeling the extracellular matrix produced by primary endothelial cells in vitro, the ability of human breast cancer cells to degrade BM components was studied. We found that T-47D, a human breast cancer line, was able to degrade significant amounts of (35S)methionine-labeled and (3H)proline-labeled BM, but not 35SO4-labeled BM. Six other tumor cell lines of human breast origin were assayed in the same manner and were found to degrade BM to varying degrees. Several non-tumormore » cell lines tested showed relatively little degrading activity. The use of serum-free medium greatly enhanced degradation of the BM by tumor cells, suggesting a role for naturally occurring enzyme inhibitors in the serum. Direct cell contact with the BM was required for BM degradation, suggesting that the active enzymes are cell associated. The addition of hormones implicated in the etiology of breast cancer did not significantly alter the ability of T-47D cells to degrade the BM. The use of this assay affords future studies on the mechanism of invasion and metastasis of human breast cancer.« less
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  • No abstract prepared.
  • The authors report that human breast cancer cells secrete a growth factor that is biologically and immunologically similar to platelet-derived growth factor (PDGF). Serum-free medium conditioned by estrogen-independent MDA-MB-231 or estrogen-dependent MCF-7 cells contains a mitogenic or competence activity that is capable of inducing incorporation of (/sup 3/H) thymidine into quiescent Swiss 3T3 cells in the presence of platelet-poor plasma. Like authentic PDGF, the PDGF-like activity produced by breast cancer cells is stable after acid and heat treatment (95/sup 0/C) and inhibited by reducing agents. The mitogenic activity comigrates with a material of approx. =30 kDa on NaDodSO/sub 4//polyacrylamide gels.more » Immunoprecipitation with PDGF antiserum of proteins from metabolically labeled cell lysates and conditioned medium followed by analysis on nonreducing NaDodSO/sub 4//polyacrylamide gels identified proteins of 30 and 34 kDa. Upon reduction, the 30- and 34-kDa bands were converted to 15- and 16-kDa bands suggesting that the immunoprecipitated proteins were made up of two disulfide-linked polypeptides similar to PDGF. Hybridization studies with cDNA probes for the A chain PDGF and the B chain of PDGF/SIS identified transcripts for both PDGF chains in the MCF-7 and MDA-MB-231 cells. The data summarized above provide conclusive evidence for the synthesis and hormonally regulated secretion of a PDGF-like mitogen by breast carcinoma cells. Production of a PDGF-like growth factor by breast cancer cell lines may be important in mediating paracrine stimulation of tumor growth.« less
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