title: Enhanced invasiveness of breast cancer cell lines upon co-cultivation with macrophages is due to TNF-alpha dependent up-regulation of matrix metalloproteases.
abstract: Apart from the neoplastic cells, malignant tumours consist of the extracellular matrix (ECM) and normal cells, in particular tumour-associated macrophages (TAM). To understand the mechanisms by which TAM can influence tumour cell invasion we co-cultured the human breast cancer cell lines MCF-7, SK-BR-3 and the benign mammary epithelial cell line hTERT-HME1 with macrophages. Co-incubation enhanced invasiveness of the tumour cells, while hTERT-HME1 remained non-invasive. Addition of the broad-spectrum matrix metalloprotease (MMP)-inhibitor FN 439, neutralizing MMP-9 or tumour necrosis factor-alpha (TNF-alpha) antibodies reduced invasiveness to basal levels. As shown by zymography, all cell lines produced low amounts of MMP-2, -3, -7 and -9 under control conditions. Basal MMP production by macrophages was significantly higher. Upon co-incubation, supernatant levels of MMPs -2, -3, -7 and -9 increased significantly, paralleled by an increase of MMP-2 activation. MMP-2 and -9 induction could be blocked by TNF-alpha antibodies. Co-culture of macrophages and hTERT-HME1 did not lead to MMP induction. In the co-cultures, mRNAs for MMPs and TNF-alpha were significantly up-regulated in macrophages, while the mRNA concentrations in the tumour cells remained unchanged. In summary, we have found that co-cultivation of tumour cells with macrophages leads to enhanced invasiveness of the malignant cells due to TNF-alpha dependent MMP induction in the macrophages.
authors.affiliation: Department of Haematology/Oncology, Georg-August-University, Göttingen, Germany.
authors.forename: Thorsten
authors.initials: T
authors.lastname: Hagemann
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Robinson
authors.forename: Matthias
authors.initials: M
authors.lastname: Schulz
authors.forename: Lorenz
authors.initials: L
authors.lastname: Trümper
authors.forename: Frances R
authors.initials: FR
authors.lastname: Balkwill
authors.forename: Claudia
authors.initials: C
authors.lastname: Binder
mesh_terms: D001943:Breast Neoplasms / Q000473:pathology*; D002460:Cell Line; D045744:Cell Line, Tumor; D018920:Coculture Techniques; D003094:Collagen / Q000494:pharmacology; D003720:Densitometry; D015536:Down-Regulation; D004338:Drug Combinations; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007797:Laminin / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000378:metabolism; D008264:Macrophages / Q000378:metabolism*; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism; D019278:Matrix Metalloproteinase 3 / Q000096:biosynthesis; D020783:Matrix Metalloproteinase 7 / Q000096:biosynthesis; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D020782:Matrix Metalloproteinases / Q000096:biosynthesis*; D009361:Neoplasm Invasiveness; D011509:Proteoglycans / Q000494:pharmacology; D012313:RNA / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis*; D015854:Up-Regulation
chemical_list: D004338:Drug Combinations; D007797:Laminin; D008070:Lipopolysaccharides; D011509:Proteoglycans; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; C059485:matrigel; D012313:RNA; D003094:Collagen; D020782:Matrix Metalloproteinases; D019278:Matrix Metalloproteinase 3; D020783:Matrix Metalloproteinase 7; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9