title: Angiotensin II as a factor modulating protein tyrosine kinase activity in two breast cancer lines - MCF-7 and MDA-MB-231.
abstract: BACKGROUND
  Angiotensin II (AngII), a peptide that regulates the water-electrolytic balance and blood pressure, is also known to influence cell proliferation. It can either induce cell growth, when binding to angiotensin type-I receptor, or trigger growth inhibition via angiotensin type-II receptor. AngII stimulates proliferation of some normal and tumour cell lines, e.g. pituitary, adrenal glands and breast cancer.
  
  
  METHODS
  The aim of this study was to evaluate possible AngII effect on the growth of two breast cancer cell lines - hormone-dependent MCF-7 and hormone-independent MDA-MB-231. We measured tyrosine kinase activity as a potential proliferation marker. We also estimated the influence of 17b-oestradiolon AngII-induced changes.
  
  
  RESULTS
  In the MDA-MB-231 line, AngII radically slowed the activity of tyrosine kinases and 17b-oestradiol only at a concentration of 10⁻⁶ M, while it enhanced the effect of angiotensin II at a concentration of 10⁻⁹ M. In MCF-7, Ang II had a strong inhibitory effect in the presence of oestradiol (10⁻⁶ M). Oestradiol alone decreased the activity of examined enzymes in both cell lines. AngII receptor type 1 was found in both studied lines, but type 2 only in MDA-MB-231.
  
  
  CONCLUSIONS
  Our results show that AngII can modulate tyrosine kinase activity in breast tumour cell lines.
authors.affiliation: Department of Medical Enzymology, Medical University, Łódź, Poland.
authors.forename: Urszula
authors.initials: U
authors.lastname: Lewandowska
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Lachowicz-Ochędalska
authors.forename: Kamila
authors.initials: K
authors.lastname: Domińska
authors.forename: Dominika
authors.initials: D
authors.lastname: Kaszewska
authors.forename: Elżbieta
authors.initials: E
authors.lastname: Rębas
mesh_terms: D000704:Analysis of Variance; D000804:Angiotensin II / Q000494:pharmacology*; D045744:Cell Line, Tumor / Q000187:drug effects / Q000378:metabolism; D049109:Cell Proliferation / Q000187:drug effects*; D004958:Estradiol / Q000378:metabolism*; D005260:Female; D006801:Humans; D016133:Polymerase Chain Reaction; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D014407:Tumor Cells, Cultured
chemical_list: D000804:Angiotensin II; D004958:Estradiol; D011505:Protein-Tyrosine Kinases