Fiche publication


Date publication

mai 2000

Journal

The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society

Auteurs

Membres identifiés du Cancéropôle Est :
Pr POLETTE Myriam


Tous les auteurs :
Catusse C, Polette M, Coraux C, Burlet H, Birembaut P

Résumé

During tumor progression, the extracellular matrix (ECM) and particularly the basement membrane (BM) appear to be dynamic structures that are not only degraded but also deposited around tumor clusters. In this study we examined by immunohistochemistry the localization of three chains of Type IV collagen (alpha1, alpha3 and alpha5), Type VII collagen, and laminin 5 at different stages of bronchopulmonary cancers. In normal tissues, alpha1(IV) chain was detected in all BMs (bronchial, vascular, alveolar, and glandular), alpha5(IV) chain was present only in vascular BM, and laminin 5 and Type VII collagen were co-localized in bronchial and glandular BMs, whereas alpha3(IV) immunolabeling was totally absent from normal bronchi. In well-differentiated carcinomas, alpha3(IV) chain staining was found in some neosynthetized BMs interfacing the tumor cell and the stromal compartment, contrasting with the total absence of labeling in normal tissues. alpha1(IV) chain showed strong reactivity in all BM. Laminin 5 and Type VII collagen were also detected in neosynthetized BM. In poorly differentiated invasive cancers, alpha3(IV) chain and Type VII collagen were not found, whereas laminin 5 and alpha1(IV) chain persisted. The most important modifications in BM composition during tumor progression therefore appear to be the appearance of the alpha3 (IV) chain in well-differentiated carcinomas and its subsequent disappearance in poorly differentiated carcinomas, together with the loss of type VII collagen. alpha5(IV) chain distribution was restricted in vascular BM of well- and poorly differentiated carcinomas. These results show that the composition of BM is modified during the progression of bronchopulmonary tumor, emphasizing that the BM represents a dynamic element in tumor progression and has an important role in tumor cell invasiveness.

Mots clés

Adenocarcinoma, metabolism, Adult, Basement Membrane, metabolism, Bronchi, cytology, Carcinoma, Squamous Cell, metabolism, Cell Adhesion Molecules, metabolism, Collagen, classification, Disease Progression, Humans, Immunohistochemistry, Lung, cytology, Lung Neoplasms, metabolism, Neoplasm Invasiveness, Reference Values

Référence

J. Histochem. Cytochem.. 2000 May;48(5):663-9