FURTHER CHARACTERIZATION OF A THERMOSENSITIVE TRANSFORMATION VARIANT OF MOUSE FIBROBLASTS
Temperature-sensitive (ts) variants that express a transformed phenotype at low (33°) but not at high (38.5°) temperature were isolated from a mouse fibroblast strain C3H2K cells. Among these variants, cloned ts-12B cells showed at 38.5° a density-dependent inhibition of growth typical of normal fib...
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Published in | GANN Japanese Journal of Cancer Research Vol. 71; no. 6; pp. 775 - 783 |
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Main Authors | , |
Format | Journal Article |
Language | English |
Published |
Japan
The Japanese Cancer Association
01.01.1980
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Subjects | |
Online Access | Get full text |
ISSN | 0016-450X |
DOI | 10.20772/cancersci1959.71.6_775 |
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Abstract | Temperature-sensitive (ts) variants that express a transformed phenotype at low (33°) but not at high (38.5°) temperature were isolated from a mouse fibroblast strain C3H2K cells. Among these variants, cloned ts-12B cells showed at 38.5° a density-dependent inhibition of growth typical of normal fibroblasts cultured in vitro. However, at low temperature they lost this capacity and grew to a higher saturation density. The ts variant was also temperature-sensitive as regards serum requirement: it required a higher concentration of serum for growth at 38.5° than at 33°. However, the cells behaved at both temperatures like the parent strain, possessing anchorage-dependence for growth and fibronectin, whereas they were like transformed cells with respect to release of high fibrinolytic activity. No type-C virus core protein p30 was detected at either temperature. Thus, various parameters of transformation in vitro were independently regulated in these variant cells. |
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AbstractList | Temperature-sensitive (ts) variants that express phenotype at low (33 degrees) but not at high (38.5 degrees) temperature were isolated from a mouse fibroblast strain C3H2K cells. Among these variants, cloned ts-12B cells showed at 38.5 degrees a density-dependent inhibition of growth typical of normal fibroblasts cultured in vitro. However, at low temperature they lost this capacity and grew to a higher saturation density. The ts variant was also temperature-sensitive as regards serum requirement: it required a higher concentration of serum for growth at 38.5 degrees than at 33 degrees. However, the cells behaved at both temperatures like the parent strain, possessing anchorage-dependence for growth and fibronectin, whereas they were like transformed cells with respect to release of high fibrinolytic activity. No type-C virus core protein p30 was detected at either temperature. Thus, various parameters of transformation in vitro were independently regulated in these variant cells.Temperature-sensitive (ts) variants that express phenotype at low (33 degrees) but not at high (38.5 degrees) temperature were isolated from a mouse fibroblast strain C3H2K cells. Among these variants, cloned ts-12B cells showed at 38.5 degrees a density-dependent inhibition of growth typical of normal fibroblasts cultured in vitro. However, at low temperature they lost this capacity and grew to a higher saturation density. The ts variant was also temperature-sensitive as regards serum requirement: it required a higher concentration of serum for growth at 38.5 degrees than at 33 degrees. However, the cells behaved at both temperatures like the parent strain, possessing anchorage-dependence for growth and fibronectin, whereas they were like transformed cells with respect to release of high fibrinolytic activity. No type-C virus core protein p30 was detected at either temperature. Thus, various parameters of transformation in vitro were independently regulated in these variant cells. Temperature-sensitive (ts) variants that express phenotype at low (33 degrees) but not at high (38.5 degrees) temperature were isolated from a mouse fibroblast strain C3H2K cells. Among these variants, cloned ts-12B cells showed at 38.5 degrees a density-dependent inhibition of growth typical of normal fibroblasts cultured in vitro. However, at low temperature they lost this capacity and grew to a higher saturation density. The ts variant was also temperature-sensitive as regards serum requirement: it required a higher concentration of serum for growth at 38.5 degrees than at 33 degrees. However, the cells behaved at both temperatures like the parent strain, possessing anchorage-dependence for growth and fibronectin, whereas they were like transformed cells with respect to release of high fibrinolytic activity. No type-C virus core protein p30 was detected at either temperature. Thus, various parameters of transformation in vitro were independently regulated in these variant cells. Temperature-sensitive (ts) variants that express a transformed phenotype at low (33°) but not at high (38.5°) temperature were isolated from a mouse fibroblast strain C3H2K cells. Among these variants, cloned ts-12B cells showed at 38.5° a density-dependent inhibition of growth typical of normal fibroblasts cultured in vitro. However, at low temperature they lost this capacity and grew to a higher saturation density. The ts variant was also temperature-sensitive as regards serum requirement: it required a higher concentration of serum for growth at 38.5° than at 33°. However, the cells behaved at both temperatures like the parent strain, possessing anchorage-dependence for growth and fibronectin, whereas they were like transformed cells with respect to release of high fibrinolytic activity. No type-C virus core protein p30 was detected at either temperature. Thus, various parameters of transformation in vitro were independently regulated in these variant cells. |
Author | LIAW, Wen-Shing ANDOH, Toshiwo |
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References_xml | – reference: 28) Rudland, P. S., Pearlstein, E., Kamely, D., Nuff, M., Eckhart, W., Nature (London), 256, 43-46 (1975). – reference: 29) Sachs, L., Curr. Top. Dev. Biol., 2, 129-145 (1967). – reference: 12) Hunter, W. M., "Handbook of Experimental Immunology," 2nd Ed., ed. D. M. Weir, pp. 608-642 (1973). F. A. Davis, Philadelphia. – reference: 13) Hynes, R. O., Proc. Natl. Acad. Sci. U. S. A., 70, 3170-3174 (1973). – reference: 24) Pearlstein, E., Hynes, R. O., Franks, L. M., Hemming, V. J., Cancer Res., 36, 1475-1580 (1976). – reference: 8) Gallimore, P. H., McDougall, J. K., Chen, L. B., Cell, 10, 669-675 (1977). – reference: 22) Nakano, N., Tohoku J. Exp. Med., 88, 69-84 (1966). – reference: 14) Hynes, R. O., Biochim. Biophys. Acta, 458, 73-107 (1976). – reference: 18) Laemmli, U. K., Nature (London), 227, 680-685 (1970). – reference: 19) Liaw, W. S., Andoh, T., Jpn. J. Exp. Med., 47, 49-57 (1977). – reference: 34) Strand, M., August, S. T., J. Virol., 14, 1583-1596 (1974). – reference: 3) Burger, M. M., Proc. Natl. Acad. Sci. U. S. A., 62, 994-1001 (1969). – reference: 35) Todaro, G. J., Nature New Biol., 240, 157-160 (1972). – reference: 33) Stoker, M., O'Neill, C., Berryman, S., Maxman, V., Int. J. Cancer, 3, 683-693 (1968). – reference: 17) Kelsey, W. E., Shimada, T., Cancer Res., 38, 624-634 (1978). – reference: 6) Freedman, V. H., Shin, S., Cell, 3, 355-359 (1974). – reference: 5) Dulbecco, R., Nature (London), 227, 802-806 (1970). – reference: 11) Ham, R. G., Methods Cell Physiol., 5, 37-74 (1972). – reference: 40) Yoshikura, H., Hirokawa, Y., Yamada, M., Exp. Cell Res., 48, 226-228 (1967). – reference: 16) Jones, P. A., Lang, W. E., Gardener, A., Nye, C. A., Fink, C. M., Benedict, W. F., Cancer Res., 36, 2863-2867 (1976). – reference: 27) Reznikoff, C. A., Brankow, D. W., Heidelberger, C., Cancer Res., 33, 3231-3238 (1973). – reference: 30) Shin, S., Freedman, V. H., Risser, R., Pollack, R., Proc. Natl. Acad. Sci. U. S. A., 72, 4435-4439 (1975). – reference: 31) Spadidos, D. A., Siminovitch, L., Nature (London), 271, 259-261 (1978). – reference: 23) Ossowski, L., Unkelless, J. C., Tobia, A., Quigley, J. P., Rifkin, D. B., Reich, E., J. Exp. Med., 137, 112-126 (1973). – reference: 15) Ishii, Y., Elliott, J. A., Mishra, N. K., Lieberman, M. W., Cancer Res., 37, 2023-2029 (1977). – reference: 39) Weiss, R. A., Friis, R. R., Katz, E., Vogt, P. K., Virology, 46, 920-938 (1971). – reference: 1) Barrett, J. C, Ts'o, O. P., Proc. Natl. Acad. Sci. U. S. A., 75, 3761-3765 (1978). – reference: 2) Basilico, C., Adv. Cancer Res., 24, 223-266 (1977). – reference: 32) Stiles, C. D., Desmond, W., Chuman, L. M., Sato, G., Saier, M. H., Jr., Cancer Res., 36, 3300-3305 (1976). – reference: 26) Renger, H. C., Basilico, C., Proc. Natl. Acad. Sci. U. S. A., 69, 109-114 (1972). – reference: 20) Miyashita, K., Kakunaga, T., Cell, 5, 131-138 (1975). – reference: 38) Unkelless, J. C., Tobia, A., Ossowski, L., Quigley, J. P., Rifkin, D. B., Reich, E., J. Exp. Med., 137, 85-111 (1973). – reference: 9) Gospodarowicz, D., Moran, J. A., Ann. Rev. Biockem., 45, 531-538 (1976). – reference: 7) Freedman, V. H., Gilden, R. V., Vernon, M. L., Wolford, R. G., Hugunin, P. E., Huebner, R. J., Proc. Natl. Acad. Sci. U. S. A., 70, 2415-2419 (1973). – reference: 36) Toniolo, D., Basilico, C., Cell, 4, 255-262 (1975). – reference: 25) Pollack, R. E., Risser, R., Conlon, S., Rifkin, D., Proc. Natl. Acad. Sci. U. S. A., 71, 4792-4796 (1974). – reference: 4) Casto, B. C., Dipaolo, J. A., "Progress in Medical Virology," Vol. 16, ed. J. L. Melnick, pp. 1-47 (1973). S. Karger, Basel. – reference: 21) MacPherson, I., Montagnier, L., Virology, 23, 291-294 (1964). – reference: 37) Tooze, J., "The Molecular Biology of Tumor Viruses," pp. 350-402 (1973). Cold Spring Harbor Laboratory, New York. – reference: 10) Hakomori, S., Biochim. Biophys. Acta, 417, 55-89 (1975). – reference: 41) Yoshikura, H., Hirokawa, Y., Yamada, M., Sugano, H., Jpn. J. Med. Sci. Biol., 20, 225-236 (1967). |
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Snippet | Temperature-sensitive (ts) variants that express a transformed phenotype at low (33°) but not at high (38.5°) temperature were isolated from a mouse fibroblast... Temperature-sensitive (ts) variants that express phenotype at low (33 degrees) but not at high (38.5 degrees) temperature were isolated from a mouse fibroblast... |
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SubjectTerms | Anchorage dependence Animals Blood Cell Transformation, Neoplastic Cells, Cultured Culture Media Endogenous type-C virus Fibrinolytic activity Fibrinolytic Agents - secretion Fibroblasts - microbiology Fibroblasts - pathology Fibronectins - analysis Mice Mutation Retroviridae - isolation & purification Saturation density Serum requirement Temperature Temperature-sensitive variant Transformation |
Title | FURTHER CHARACTERIZATION OF A THERMOSENSITIVE TRANSFORMATION VARIANT OF MOUSE FIBROBLASTS |
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