Type V/type I collagen interactions in vitro and growth-inhibitory effect of hybrid substrates on 8701-BC carcinoma cells.
Different ratios of type V and I collagens were submitted to mixed fibrillogenesis followed by localization of type V collagen within the aggregates by immunoelectron microscopy. At lower concentrations (10-30%), type V collagen segregates into aperiodic filamentous material, peripheral to the cross-banded type I fibrils but making contact in an apparently random manner. Increasing the ratio of type V collagen up to 50% causes the disappearance of collagen fibrils and the formation of a sticky gel composed of weakly immunoreactive long-spacing structures, interspersed with intensely labeled amorphous material. Hybrid type V/type I matrices changed the growth behaviour of 8701-BC carcinoma cells, with inhibition of cell growth being directly related to type V content. This restraining influence on growth was partially reversed when substrates were pre-incubated with low dilutions of anti-type V serum, prior to cell seeding. These findings suggest that the high concentrations of type V collagen, known to exist in vivo in some scirrhous tumors like ductal infiltrating carcinoma of the breast, perturb the normal fibrous architecture of the stroma and concurrently inhibit neoplastic cell growth.
Pucci-Minafra
I
I
Dipartimento di Biologia Cellulare e dello Sviluppo, Università di Palermo, Italia.
Luparello
C
C
D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000648:ultrastructure; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D002471:Cell Transformation, Neoplastic / Q000187:drug effects* / Q000473:pathology / Q000648:ultrastructure; D003094:Collagen / Q000378:metabolism* / Q000502:physiology / Q000648:ultrastructure; D005109:Extracellular Matrix / Q000502:physiology; D006131:Growth Inhibitors / Q000502:physiology*; D006801:Humans; D016253:Microscopy, Immunoelectron; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000473:pathology / Q000648:ultrastructure
D006131:Growth Inhibitors; D003094:Collagen