title: Regulation of tissue-degrading factors and in vitro invasiveness in progression of breast cancer cells.
abstract: Hormone-independent growth and invasiveness represent phenotypic properties acquired during early progression of breast cancer. We compared human mammary adenocarcinoma cells, MCF-7, which are estrogen-dependent and poorly metastatic, with the estrogen-independent and highly metastatic subline, MCF7/LCC1, with regard to expression of tissue-degrading factors of the matrix metalloproteinase (MMP)-and urokinase (uPA)-dependent degradative pathways, as well as for their in vitro invasive properties. Both cell lines showed low constitutive mRNA expression of the MMP inhibitor TIMP-1. Baseline expression of TIMP-2 mRNA was also very low in MCF-7 cells, whereas the MCF7/LCC1 level was much higher (approximately 10-fold). Furthermore, both cell lines revealed low constitutive capacity to migrate in an in vitro invasion assay. Treatment with 12-O-tetradecanoylphorbol-13-acetate (TPA; 100 nM) induced the mRNAs for TIMP-1 as well as for MMP-1, MMP-9, the uPA receptor, and the uPA inhibitor PAI-1, amongst which only the responses of MMP-9 and PAI-1 were cell-specific. The mRNA levels of MMP-9 and PAI-1 were approximately 10-fold and approximately 15-fold higher in MCF7/LCC1 cells compared to MCF-7 cells. The secretion of immunoreactive PAI-1 was considerably elevated (> 20-fold) in TPA-treated MCF7/LCC1 cells, whereas the TPA-dependent level of 92-kDa MMP-9 was only approximately 2-fold higher in MCF7/LCC1 cells than in MCF-7 cells. In both cell lines treatment with TPA was associated with an increase (approximately 10-fold) in in vitro migration, which in the MCF7/LCC1 cells was significantly attenuated by a reconstituted basement membrane extract (Matrigel). These data suggest that TPA-responsive in vitro invasive properties that are probably associated with PAI-1 expression may co-vary with progression from hormone-dependent to -independent breast cancer.
authors.affiliation: Department of Tumor Biology, The Norwegian Radium Hospital, Institute of Medical Biochemistry, Oslo. a.h.ree.@dnr.uio.no
authors.forename: A H
authors.initials: AH
authors.lastname: Ree
authors.forename: K
authors.initials: K
authors.lastname: Bjørnland
authors.forename: N
authors.initials: N
authors.lastname: Brünner
authors.forename: H T
authors.initials: HT
authors.lastname: Johansen
authors.forename: K B
authors.initials: KB
authors.lastname: Pedersen
authors.forename: A O
authors.initials: AO
authors.lastname: Aasen
authors.forename: O
authors.initials: O
authors.lastname: Fodstad
mesh_terms: D001943:Breast Neoplasms / Q000201:enzymology / Q000473:pathology*; D002465:Cell Movement; D005109:Extracellular Matrix / Q000378:metabolism; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008666:Metalloendopeptidases / Q000235:genetics; D009361:Neoplasm Invasiveness; D017395:Plasminogen Activator Inhibitor 1 / Q000378:metabolism; D011493:Protein Kinase C / Q000502:physiology; D012333:RNA, Messenger / Q000235:genetics; D012334:RNA, Neoplasm / Q000235:genetics; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000235:genetics; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000235:genetics; D014407:Tumor Cells, Cultured; D014568:Urokinase-Type Plasminogen Activator / Q000235:genetics
chemical_list: D017395:Plasminogen Activator Inhibitor 1; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D019715:Tissue Inhibitor of Metalloproteinase-1; D019716:Tissue Inhibitor of Metalloproteinase-2; D011493:Protein Kinase C; D014568:Urokinase-Type Plasminogen Activator; D008666:Metalloendopeptidases; D013755:Tetradecanoylphorbol Acetate