Collagens, integrins and the mesenchymal drift in glioblastomas: a comparison of biopsy specimens, spheroid and early monolayer cultures.

摘要: To analyze the process of mesenchymal differentiation in vitro, we examined 5 human glioblastomas as biopsy specimens, monolayer cultures and 3-dimensional fragment spheroid for immunohistochemical expression extracellular matrix (ECM) components (collagen types I, III-VI, laminin) integrin receptors (beta 1, beta 2, 3 4 chains). mRNA type-I type-IV collagen alpha I chains was quantified using reverse transcription-polymerase chain reaction. In situ, glioma cells expressed common most ECM receptors, while were restricted to vascular elements. Early showed a marked increase (interstitial collagens more than basement membrane components), coexpression glial fibrillary acidic protein (GFAP) by cells. 2 integrins upregulated primary cultures. fifth passages, GFAP-positive decreased collagen-expressing increased. The spheroids exhibited preserved GFAP staining, neoexpression some tumors, variable which lower that deposition usually commenced central areas where Ki-67 proliferation index low. We conclude different culture systems are characterized distinct patterns features cultured gliomas arise due transdifferentiation