Expression of beta 1 integrin in normal, dysplastic and neoplastic canine mammary gland.

The expression of beta 1 integrin was evaluated immunohistochemically in a series of normal, dysplastic and neoplastic canine mammary glands, and in lymph node metastases. The tissues were formalin-fixed and paraffin wax-embedded. In malignant neoplasms, beta 1 integrin was decreased and redistributed along the entire cell membrane. In lymph nodes, strong immunohistochemical staining was seen intercellularly in clusters of metastatic cells within subcapsular sinuses and at the periphery of intranodal metastases. These results suggest that the expression of integrin molecules may be related to malignancy and to the metastatic potential of neoplastic cells.