In vivo demonstration of cytoplasmic fibronectin in human breast carcinomas

Expression of fibronectin and its integrin receptor alpha 5 beta 1 in canine mammary tumours

Fibronectin and its integrin receptor alpha 5 beta 1 were studied by immunohistochemical methods in five normal canine mammary glands, four dysplastic glands and 18 mammary tumours. The aim of the study was to evaluate the possible changes in the alpha 5 beta 1 integrin receptor and its ligand fibronectin in relation to the metastatic capacity of canine mammary neoplasms. The immunostaining of alpha 5 beta 1 was very uniform in the hyperplastic glands but uneven in the mammary tumours. The expression of alpha 5 and beta 1 was diminished in metastatic tumours but there were some alpha 5-positive cells with pronounced features of malignancy and immaturity. Stromal fibronectin was increased in most cases and cytoplasmic staining of fibronectin was observed in epithelial and myoepithelial cells in mammary neoplasms but not in normal or dysplastic mammary tissue. There was no relationship between the content of alpha 5 beta 1 and the expression of fibronectin in canine mammary tumours.

Relationship of transforming growth factor beta 1 to extracellular matrix and stromal infiltrates in invasive breast carcinoma

Transforming growth factor beta (TGF-beta) comprises a group of multifunctional regulatory proteins, whose effects include stimulation of extracellular matrix formation and modification of immune function. The presence of TGF-beta 1 and TGF-beta 2 in invasive breast carcinomas has been determined and related to pathological features, the presence of fibronectin and tenascin and lymphocyte/macrophage infiltration, using immunohistochemistry. Differences were observed in the extent of reactivity within the same carcinoma and between tumours stained with an antibody detecting TGF-beta 1 ane one detecting TGF-beta plus TGF-beta 2, the latter having a higher level of reactivity. Prominent reactivity for TGF-beta 1 was associated with lymph node metastasis, (0.02 > P > 0.01), increased detection of cellular fibronectin, fine stromal fibronectin staining, more prominent reactivity for tenascin (0.02 > P > 0.01), the presence of tumour-associated macrophage infiltration and altered ratios of CD4 and CD8 lymphocyte populations, with CD8 lymphocytes predominating. These associations were not observed for carcinomas showing prominent staining with antibody detecting TGF-beta 2 as well as TGF-beta 1. The findings indicate that TGF-beta 1 may have a role in invasion and metastasis of breast carcinomas.

Immunohistochemical study of intimal protein deposits in the aging vascular wall of normo- and hypertensive patients

In an attempt to obtain immunohistochemical data of use for evaluating the severity and extent of intimal thickening (IT) in normo- and hypertensive patients small-sized arteries were analyzed by the immunoperoxidase staining technique for intimal deposition of albumin, fibrinogen, IgG, IgM and beta-lipoprotein. The material included surgical biopsies from 143 temporal arteries and matched autopsy samples of temporal- and interlobar renal arteries from 33 patients. The intimal protein deposits were found to reflect the presence of IT but not the state of hypertension. comparisons between the matched temporal and renal arteries showed rank correlation regarding IT as well as deposition of fibrinogen, IgG and beta-lipoprotein. However, fibrinogen was the only protein, which also showed congruous mean values for the two different arterial types. We therefore conclude that out of the 5 proteins examined in this study, fibrinogen appears to be the most reliable marker of IT in small-sized arteries.

Differentiation between metaplastic carcinomas and sarcomas of the human female breast by fibronectin

The distribution pattern of fibronectin in metaplastic carcinomas, stromal sarcomas, malignant cystosarcoma phyllodes tumours and histiocytic type lymphomas of the human female breast has been studied using the indirect immunoperoxidase technique on formalin fixed paraffin embedded tissue. Fibronectin was demonstrated as intensely stained strands between tumour cells forming an irregular network in metaplastic carcinomas and lymphomas. Stromal sarcomas and the malignant stromal component of the phyllodes tumours exhibited, in contrast, a uniform staining throughout tumour cells and stroma which was weaker than in adjacent normal-looking connective tissue. We suggest that the intense staining reaction of metaplastic carcinomas is due to the scirrhous reaction generally associated with invasive human breast carcinomas. The advantage of using fibronectin as a diagnostic tool in the differentiation of carcinoma/lymphoma versus sarcoma is the fact that the antigen is a stromal marker and its staining intensity is not influenced by the morphology or degree of differentiation of non-mesenchymal tumours.