Growth factors, extracellular matrix components and cell adhesion molecules in Warthin's tumor

: We studied expressions of various growth factors, their receptors, cell adhesion molecules and extracellular matrix components in Warthin’s tumor of the salivary gland with immunohistochemistry and reverse transcriptase‐polymerase chain reaction (RT‐PCR). Various growth factors and their receptors, such as transforming growth factor‐α (TGF‐α), heparin‐binding epidermal growth factor‐like growth factor (HB‐EGF), TGF‐β2, TG‐β3, insulin‐like growth factor (IGF)‐I and ‐II, vascular endothelial growth factor (VEGF), EGF receptor (EGFR), erb‐B4, TGF‐βRI and II, Flt and Flk‐1 and IGF receptor Iβ, were found in epithelial cells and/or in some lymphoid cells. Fibronectin, laminin, collagen type IV and tenascin were found in stroma of the lymphoid tissue. Integrins such as α3β1 and β3, Thy‐1, CD44 and VCAM‐1 were also expressed in epithelial and/or lymphoid cells. These various proteins may interact and regulate the proliferation and cell attachment of both epithelial and lymphoid components in this unique tumor.