FGF-2, TGFbeta-1, PDGF-A and respective receptors expression in pleomorphic adenoma myoepithelial cells: an in vivo and in vitro study.
Myoepithelial cells have an important role in salivary gland tumor development, contributing to a low grade of aggressiveness of these tumors. Normal myoepithelial cells are known by their suppressor function presenting increased expression of extracellular matrix genes and protease inhibitors. The importance of stromal cells and growth factors during tumor initiation and progression has been highlighted by recent literature. Many tumors result from the alteration of paracrine growth factors pathways. Growth factors mediate a wide variety of biological processes such as development, tissue repair and tumorigenesis, and also contribute to cellular proliferation and transformation in neoplastic cells.


OBJECTIVE
This study evaluated the expression of fibroblast growth factor-2 (FGF-2), transforming growth factor beta-1 (TGFbeta-1), platelet-derived growth factor-A (PDGF-A) and their respective receptors (FGFR-1, FGFR-2, TGFbetaR-II and PDGFR-alpha) in myoepithelial cells from pleomorphic adenomas (PA) by in vivo and in vitro experiments.


METHODS
Serial sections were obtained from paraffin-embedded PA samples obtained from the school's files. Myoepithelial cells were obtained from explants of PA tumors provided by surgery from different donors. Immunohistochemistry, cell culture and immunofluorescence assays were used to evaluate growth factor expression.


RESULTS
The present findings demonstrated that myoepithelial cells from PA were mainly positive to FGF-2 and FGFR-1 by immunohistochemistry and immunofluorescence. PDGF-A and PDGFR-alpha had moderate expression by immunohistochemistry and presented punctated deposits throughout cytoplasm of myoepithelial cells. FGFR-2, TGFbeta-1 and TGFbetaR-II were negative in all samples.


CONCLUSIONS
These data suggested that FGF-2 compared to the other studied growth factors has an important role in PA benign myoepithelial cells, probably contributing to proliferation of these cells through the FGFR-1.
Miguita
Lucyene
L
Department of Oral Pathology, São Leopoldo Mandic Institute and Research Center, Campinas, SP, Brazil.
Martinez
Elizabeth Ferreira
EF
de Araújo
Ney Soares
NS
de Araújo
Vera Cavalcanti
VC
D000199:Actins / Q000032:analysis; D008949:Adenoma, Pleomorphic / Q000473:pathology*; D000328:Adult; D002135:Calcium-Binding Proteins / Q000032:analysis; D002467:Cell Nucleus / Q000648:ultrastructure; D002478:Cells, Cultured; D003593:Cytoplasm / Q000648:ultrastructure; D004847:Epithelial Cells / Q000473:pathology; D005260:Female; D016222:Fibroblast Growth Factor 2 / Q000032:analysis*; D005455:Fluorescent Antibody Technique; D006801:Humans; D007150:Immunohistochemistry; D053552:Keratin-7 / Q000032:analysis; D008048:Lip Neoplasms / Q000473:pathology; D008297:Male; D008840:Microfilament Proteins / Q000032:analysis; D032342:Muscle Cells / Q000473:pathology; D009124:Muscle Proteins / Q000032:analysis; D009130:Muscle, Smooth / Q000473:pathology; D010157:Palatal Neoplasms / Q000473:pathology; D010982:Platelet-Derived Growth Factor / Q000032:analysis*; D017346:Protein Serine-Threonine Kinases / Q000032:analysis*; D051496:Receptor, Fibroblast Growth Factor, Type 1 / Q000032:analysis*; D051497:Receptor, Fibroblast Growth Factor, Type 2 / Q000032:analysis*; D020796:Receptor, Platelet-Derived Growth Factor alpha / Q000032:analysis*; D000077294:Receptor, Transforming Growth Factor-beta Type II; D018125:Receptors, Transforming Growth Factor beta / Q000032:analysis*; D012468:Salivary Gland Neoplasms / Q000473:pathology*; D053773:Transforming Growth Factor beta1 / Q000032:analysis*; D014746:Vimentin / Q000032:analysis; D055815:Young Adult; D000096985:Calponins
D000199:Actins; D002135:Calcium-Binding Proteins; D016222:Fibroblast Growth Factor 2; D053552:Keratin-7; D008840:Microfilament Proteins; D009124:Muscle Proteins; D010982:Platelet-Derived Growth Factor; D017346:Protein Serine-Threonine Kinases; D051496:Receptor, Fibroblast Growth Factor, Type 1; D051497:Receptor, Fibroblast Growth Factor, Type 2; D020796:Receptor, Platelet-Derived Growth Factor alpha; D000077294:Receptor, Transforming Growth Factor-beta Type II; D018125:Receptors, Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D014746:Vimentin; D000096985:Calponins; C075278:platelet-derived growth factor A; C496348:FGFR1 protein, human; C496353:FGFR2 protein, human