The use of the tyrosine phosphatase antagonist orthovanadate in the study of a cell proliferation inhibitor.
Incubation of murine fibroblasts with orthovanadate, a global tyrosine phosphatase inhibitor, was shown to confer a "pseudo-transformed" phenotype with regard to cell morphology and growth characteristics.  This alteration was manifested by both an increasing refractile appearance of the cells, consistent with many transformed cell lines, as well as an increase in maximum cell density was attained.  Despite the abrogation of cellular tyrosine phosphatase activity, orthovanadate-treated cells remained sensitive to the biological activity of a naturally occurring sialoglycopeptide (SGP) cell surface proliferation inhibitor.  The results indicated that tyrosine phosphatase activity, inhibited by orthovanadate, was not involved in the signal transduction pathway of the SGP.
Enebo
D J
DJ
Division of Biology, NSCORT, Kansas State University, Manhattan 66506, USA.
Hanek
G
G
Fattaey
H K
HK
Johnson
T C
TC
D000818:Animals; D002452:Cell Count; D002453:Cell Cycle; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects / Q000201:enzymology; D006131:Growth Inhibitors / Q000502:physiology*; D051379:Mice; D010641:Phenotype; D017027:Protein Tyrosine Phosphatases / Q000037:antagonists & inhibitors* / Q000378:metabolism / Q000502:physiology; D012795:Sialoglycoproteins / Q000494:pharmacology / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology; D014638:Vanadates / Q000494:pharmacology*
D006131:Growth Inhibitors; D012795:Sialoglycoproteins; D014638:Vanadates; D017027:Protein Tyrosine Phosphatases