Comparison of human tenascin expression in normal, simian-virus-40-transformed and tumor-derived cell lines.
Tenascin is a polymorphic high-molecular-mass extracellular-matrix glycoprotein composed of six similar subunits. Using two-domain-specific anti-tenascin monoclonal antibodies, we have studied the expression and distribution of tenascin in four cultured normal human fibroblasts, two simian-virus-40-(SV40)-transformed and three tumor-derived (melanoma, rhabdomyosarcoma and fibrosarcoma) cell lines. We found that (a) cultured normal human fibroblasts accumulate considerable amounts of tenascin and retain 60-90% in the extracellular matrix, while they release the remainder into the tissue-culture medium; (b) of the two SV40-transformed counterparts we have tested, the AG-280 cell line accumulates no detectable amounts of tenascin and the WI-38-VA cell line accumulates about 10-times less tenascin than its normal counterpart and releases about 90% of it into the culture medium; (c) some tumor-derived cell lines accumulate considerable amounts of tenascin, but in these cases, more than 90% is released into the culture media; (d) in normal human fibroblasts, two major tenascin isoforms, generated by alternative splicing of the mRNA precursor, are detectable (280 kDa and 190 kDa, respectively) and the lower-molecular-mass tenascin isoform is accumulated preferentially in the extracellular matrix; (e) in SV40-transformed or tumor-derived cell lines, only the higher-molecular-mass isoform is detectable and it is more sialylated than the tenascin produced by the normal human fibroblast cell lines.
Carnemolla
B
B
Laboratory of Cell Biology, Istituto Nazionale Ricerca sul Cancro, Genoa, Italy.
Borsi
L
L
Bannikov
G
G
Troyanovsky
S
S
Zardi
L
L
D015152:Blotting, Northern; D015816:Cell Adhesion Molecules, Neuronal / Q000096:biosynthesis / Q000302:isolation & purification / Q000378:metabolism*; D002461:Cell Line, Transformed; D002471:Cell Transformation, Neoplastic; D004591:Electrophoresis, Polyacrylamide Gel; D005109:Extracellular Matrix / Q000378:metabolism*; D016326:Extracellular Matrix Proteins / Q000096:biosynthesis / Q000302:isolation & purification / Q000378:metabolism*; D005347:Fibroblasts; D005354:Fibrosarcoma; D005455:Fluorescent Antibody Technique; D006801:Humans; D046911:Macromolecular Substances; D008545:Melanoma; D009363:Neoplasm Proteins / Q000378:metabolism; D012208:Rhabdomyosarcoma; D013539:Simian virus 40 / Q000235:genetics*; D019063:Tenascin; D014407:Tumor Cells, Cultured
D015816:Cell Adhesion Molecules, Neuronal; D016326:Extracellular Matrix Proteins; D046911:Macromolecular Substances; D009363:Neoplasm Proteins; D019063:Tenascin