Phosphotyrosine Protein Phosphatase Activity Is Inversely Related to Metastatic Ability in Rat Prostatic Tumor Cell Subclonal Lines

  • Lee, Han-Soo (Division of Life Sciences, College of Natural Sciences, Kangwon National University)
  • Received : 1996.04.25
  • Published : 1996.09.30


In clonal sublines with different metastatic ability derived from Dunning rat prostate tumor, phosphoamino acid levels of cellular proteins were determined. Cell lines with high metastatic ability exhibited 5-fold higher phosphotyrosine level than did cell lines with low metastatic ability, while the contents of phosphoserine and phosphothreonine were similar among cell lines examined, All cell lines showed similar activities of protein tyrosine kinases as well as overall protein kinases. Phosphotyrosine protein phosphatase (PTPP) activities of the cells with high metastatic ability were very low, compared to those of the cells with low metastatic ability, suggesting that the different phosphotyrosine levels among the cell lines were due to the difference in PTPP activities rather than protein tyrosine kinase activities. Cellular activities of prostatic acid phosphatase (PAcP), which has been reported to possess phosphotyrosine protein phosphatase activity, were shown to be inversely related to the phosphotyrosine levels and metastatic abilities of the prostate tumor cells, These results suggest that cellular PAcP activity, regulating phosphotyrosine levels of cellular proteins, is closely connected with the metastatic process in prostate tumor cells and can be utilized as a good biochemical marker for the diagnosis of metastasis of prostate tumor.




  1. Cancer Res. v.42 Isaacs, J.T.;Wake, N.;Coffey, D.S.;Sandberg, A.
  2. Nature v.227 Laemmli, U.K.
  3. Biochem. J. v.277 Lee, H.;Chu, T.M.;Li, S.S.L.;Lee, C.L.
  4. J. Biol. Chem. v.268 Lee, H.;Chose-Dastidar, J.;Winawer, S.;Friedman, E.
  5. J. Biol. Chem. v.268 Lee, H.;Hsu, S.;Winawer, S.;Friedman, E.
  6. Korean Biochem. J. (presently J. Biochem. Mol. Biol.) v.27 Lee, H.
  7. Eur. J. Biochem. v.138 Li, H.C.;Chemoff, J.;Chen, L.B.;Kirschonbaum, A.
  8. Biochemistry v.22 Lin, M.F.;Lee, C.L.;Li, S.S.L.;Chu, T.M.
  9. J. Biol. Chem. v.260 Lin, M.F.;Lee, P.;Clinton, G.M.
  10. Mol. Cell. Biol. v.6 Lin, M.F.;Lee, C.L.;Clinton, G.M.
  11. Biochem. J. v.235 Lin, M.F.;Clinton, G.M.
  12. Mol. Cell. Biol. v.8 Lin, M.F.;Clinton, G.M.
  13. Cancer Lett. v.14 Loor, R.M.;Wang, M.C.;Valenzuela, L.;Chu, T.M.
  14. Cancer Res. v.44 Lowe, F.C.;Isaacs, J.T.
  15. Cancer Res. Ther. v.5 Nicolson, G.L.
  16. Methods Enzymol. v.99 Roskoski, R. Jr.
  17. Cancer Treat. Rev. v.2 Salsbury, A.J.
  18. Cell v.20 Sefton, B.M.;Hunter, T.;Beemon, K.;Eckhart, W.
  19. The Enzymes, Vol. 17 White, M.F.;Kahn, C.R.;Boyer, P.D.(ed.);Krebs, E.G.(ed.)
  20. Am. J. Med. v.56 Yam. L.T.
  21. Cancer Res. v.17 Zeidman, I.
  22. J. Virol. v.42 Beemon, K.;Ryden, T.;McNelly, E.A.
  23. J. Biol. Chem. v.258 Chernoff, J.;Li, H.C.;Cheng, Y.S.E.;Chen, L.B.
  24. J. Virol. v.46 Cooper, J.;Nakamura, K.D.;Hunter, T.;Weber, M.J.
  25. Cancer Res. v.38 Fidler, I.J.
  26. Advances in Cancer Research, Vol. 28 Fidler, I.J.;Gersten, D.M.;Hart, I.R.;Klein, G.(ed.);Weinhouse, S.(ed.)
  27. Annu. Rev. Biochem. v.54 Hunter, T.;Cooper, J.A.