Mammary carcinoma provides highly tumourigenic and invasive reactive stromal cells.
The progression of a lesion to a carcinoma is dependent on the engagement of 'reactive stroma' that provides structural and vascular support for tumour growth and also leads to tissue reorganization and invasiveness. The composition of reactive stroma closely resembles that of granulation tissue, and myofibroblasts are thought to play a critical role in driving the stromal reaction of invasive tumours as well as of physiological wound repair. In the present work, we established a myofibroblast-like cell line, named A17, from a mouse mammary carcinoma model in which tumourigenesis is triggered in a single step by the overexpression of HER-2/neu transgene in the epithelial compartment of mammary glands. We showed that although they derived from a tumour of epithelial origin and did not express HER-2/neu transgene, their subcutaneous injection into the backs of syngeneic mice gave rise to sarcomatoid tumours which expressed alpha-smooth muscle actin at the invasive edge. The expression of cytokeratin 14 suggested a myoepithelial origin but immunophenotypical profile, invasive and neoangiogenic potential of A17 cells and tumours showed many similarities with the reactive stroma that occurs in wound repair and in cancerogenesis. Our results suggest that epithelial tumours have the potential to develop highly tumourigenic and invasive reactive stromal cells and our cell line represents a novel, effective model for studying epithelial-stromal interaction and the role of myofibroblasts in tumour development.
Department of Morphological and Biomedical Sciences, Section Anatomy and Histology, University of Verona, Verona, Italy. mirco@anatomy.univr.it
Mirco
M
Galiè
Carlo
C
Sorrentino
Maura
M
Montani
Luigi
L
Micossi
Emma
E
Di Carlo
Tommaso
T
D'Antuono
Laura
L
Calderan
Pasquina
P
Marzola
Donatella
D
Benati
Flavia
F
Merigo
Fiorenza
F
Orlando
Arianna
A
Smorlesi
Cristina
C
Marchini
Augusto
A
Amici
Andrea
A
Sbarbati
D000818:Animals; D015153:Blotting, Western; D004847:Epithelial Cells / Q000378:metabolism / Q000473:pathology*; D005260:Female; D005347:Fibroblasts / Q000378:metabolism / Q000473:pathology*; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D016130:Immunophenotyping; D007279:Injections, Subcutaneous; D009682:Magnetic Resonance Spectroscopy; D008325:Mammary Neoplasms, Experimental / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D008324:Mammary Tumor Virus, Mouse / Q000235:genetics; D051379:Mice; D008822:Mice, Transgenic; D009361:Neoplasm Invasiveness / Q000473:pathology*; D016133:Polymerase Chain Reaction; D051381:Rats; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism*; D012192:Retroviridae Infections / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D012509:Sarcoma / Q000473:pathology; D017154:Stromal Cells / Q000378:metabolism / Q000473:pathology*; D016212:Transforming Growth Factor beta / Q000378:metabolism; D014407:Tumor Cells, Cultured; D014412:Tumor Virus Infections / Q000235:genetics / Q000378:metabolism / Q000473:pathology
D018719:Erb-b2 Receptor Tyrosine Kinases; D016212:Transforming Growth Factor beta