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Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1991 Dec 1;88(23):10652–10656. doi: 10.1073/pnas.88.23.10652

Role of transfection and clonal selection in mediating radioresistance.

F S Pardo 1, R G Bristow 1, A Taghian 1, A Ong 1, C Borek 1
PMCID: PMC52988  PMID: 1961732

Abstract

Transfected oncogenes have been reported to increase the radioresistance of rodent cells. Whether transfected nononcogenic DNA sequences and subsequent clonal selection can result in radioresistant cell populations is unknown. The present set of experiments describe the in vitro radiosensitivity and tumorigenicity of selected clones of primary rat embryo cells and human glioblastoma cells, after transfection with a neomycin-resistance marker (pSV2neo or pCMVneo) and clonal selection. Radiobiological data comparing the surviving fraction at 2 Gy (SF2) and the mean inactivation dose show the induction of radioresistance in two rat embryo cell clones and one glioblastoma clone, as compared to untransfected cells. Wild-type and transfectant clones were injected into three strains of immune-deficient mice (scid, NIH, and nu/nu) to assay for tumorigenicity and metastatic potential. Only the glioblastoma parent line and its transfectant clones were tumorigenic. None of the cells produced spontaneous or experimentally induced metastases. Flow cytometric analyses indicated that the induction of radioresistance could not be attributed to changes in cell kinetics at the time of irradiation. Our results show that transfection of a neomycin-resistance marker and clonal selection can impart radioresistance on both normal and tumor cells. The work also indicates that altered radiation sensitivity does not necessarily correlate with changes in cell-cycle kinetics at the time of irradiation, tumorigenicity, or altered metastatic potential. Our findings have critical implications for transfection studies investigating determinants of cellular radiosensitivity.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. BENDER M. A., GOOCH P. C. The kinetics of x-ray survival of mammalian cells in vitro. Int J Radiat Biol Relat Stud Phys Chem Med. 1962 May;5:133–145. doi: 10.1080/09553006214550651. [DOI] [PubMed] [Google Scholar]
  2. Benson M. C., McDougal D. C., Coffey D. S. The application of perpendicular and forward light scatter to assess nuclear and cellular morphology. Cytometry. 1984 Sep;5(5):515–522. doi: 10.1002/cyto.990050513. [DOI] [PubMed] [Google Scholar]
  3. Borek C., Hall E. J., Rossi H. H. Malignant transformation in cultured hamster embryo cells produced by X-rays, 460-keV monoenergetic neutrons, and heavy ions. Cancer Res. 1978 Sep;38(9):2997–3005. [PubMed] [Google Scholar]
  4. Borek C. Neoplastic transformation in vitro of a clone of adult liver epithelial cells into differentiated hepatoma-like cells under conditions of nutritional stress. Proc Natl Acad Sci U S A. 1972 Apr;69(4):956–959. doi: 10.1073/pnas.69.4.956. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Borek C., Ong A., Mason H. Distinctive transforming genes in x-ray-transformed mammalian cells. Proc Natl Acad Sci U S A. 1987 Feb;84(3):794–798. doi: 10.1073/pnas.84.3.794. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Bristow R. G., Hill R. P. Comparison between in vitro radiosensitivity and in vivo radioresponse in murine tumor cell lines. II: In vivo radioresponse following fractionated treatment and in vitro/in vivo correlations. Int J Radiat Oncol Biol Phys. 1990 Feb;18(2):331–345. doi: 10.1016/0360-3016(90)90098-5. [DOI] [PubMed] [Google Scholar]
  7. Deschavanne P. J., Debieu D., Fertil B., Malaise E. P. Re-evaluation of in vitro radiosensitivity of human fibroblasts of different genetic origins. Int J Radiat Biol Relat Stud Phys Chem Med. 1986 Aug;50(2):279–293. doi: 10.1080/09553008614550661. [DOI] [PubMed] [Google Scholar]
  8. Fertil B., Dertinger H., Courdi A., Malaise E. P. Mean inactivation dose: a useful concept for intercomparison of human cell survival curves. Radiat Res. 1984 Jul;99(1):73–84. [PubMed] [Google Scholar]
  9. Fertil B., Deschavanne P. J., Lachet B., Malaise E. P. In vitro radiosensitivity of six human cell lines: a comparative study with different statistical models. Radiat Res. 1980 May;82(2):297–309. [PubMed] [Google Scholar]
  10. Fertil B., Malaise E. P. Inherent cellular radiosensitivity as a basic concept for human tumor radiotherapy. Int J Radiat Oncol Biol Phys. 1981 May;7(5):621–629. doi: 10.1016/0360-3016(81)90377-1. [DOI] [PubMed] [Google Scholar]
  11. Fertil B., Malaise E. P. Intrinsic radiosensitivity of human cell lines is correlated with radioresponsiveness of human tumors: analysis of 101 published survival curves. Int J Radiat Oncol Biol Phys. 1985 Sep;11(9):1699–1707. doi: 10.1016/0360-3016(85)90223-8. [DOI] [PubMed] [Google Scholar]
  12. Gray J. W., Dolbeare F., Pallavicini M. G., Beisker W., Waldman F. Cell cycle analysis using flow cytometry. Int J Radiat Biol Relat Stud Phys Chem Med. 1986 Feb;49(2):237–255. doi: 10.1080/09553008514552531. [DOI] [PubMed] [Google Scholar]
  13. Kano Y., Little J. B. Mechanisms of human cell neoplastic transformation: X-ray-induced abnormal clone formation in long-term cultures of human diploid fibroblasts. Cancer Res. 1985 Jun;45(6):2550–2555. [PubMed] [Google Scholar]
  14. Kerbel R. S., Waghorne C., Korczak B., Breitman M. L. Clonal changes in tumours during growth and progression evaluated by southern gel analysis of random integrations of foreign DNA. Ciba Found Symp. 1988;141:123–148. doi: 10.1002/9780470513736.ch8. [DOI] [PubMed] [Google Scholar]
  15. Lambert M., Borek C. X-ray-induced changes in gene expression in normal and oncogene-transformed rat cell lines. J Natl Cancer Inst. 1988 Nov 16;80(18):1492–1497. doi: 10.1093/jnci/80.18.1492. [DOI] [PubMed] [Google Scholar]
  16. McKenna W. G., Iliakis G., Weiss M. C., Bernhard E. J., Muschel R. J. Increased G2 delay in radiation-resistant cells obtained by transformation of primary rat embryo cells with the oncogenes H-ras and v-myc. Radiat Res. 1991 Mar;125(3):283–287. [PubMed] [Google Scholar]
  17. McKenna W. G., Weiss M. C., Bakanauskas V. J., Sandler H., Kelsten M. L., Biaglow J., Tuttle S. W., Endlich B., Ling C. C., Muschel R. J. The role of the H-ras oncogene in radiation resistance and metastasis. Int J Radiat Oncol Biol Phys. 1990 Apr;18(4):849–859. doi: 10.1016/0360-3016(90)90407-b. [DOI] [PubMed] [Google Scholar]
  18. Ossowski L., Reich E. Loss of malignancy during serial passage of human carcinoma in culture and discordance between malignancy and transformation parameters. Cancer Res. 1980 Jul;40(7):2310–2315. [PubMed] [Google Scholar]
  19. Peters L. J., Brock W. A., Johnson T., Meyn R. E., Tofilon P. J., Milas L. Potential methods for predicting tumor radiocurability. Int J Radiat Oncol Biol Phys. 1986 Apr;12(4):459–467. doi: 10.1016/0360-3016(86)90053-2. [DOI] [PubMed] [Google Scholar]
  20. Rubin A. L., Yao A., Rubin H. Relation of spontaneous transformation in cell culture to adaptive growth and clonal heterogeneity. Proc Natl Acad Sci U S A. 1990 Jan;87(1):482–486. doi: 10.1073/pnas.87.1.482. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Rubin H. The significance of biological heterogeneity. Cancer Metastasis Rev. 1990 Jul;9(1):1–20. doi: 10.1007/BF00047585. [DOI] [PubMed] [Google Scholar]
  22. Silobrcic V., Zietman A. L., Ramsay J. R., Suit H. D., Sedlacek R. S. Residual immunity of athymic NCr/Sed nude mice and the xenotransplantation of human tumors. Int J Cancer. 1990 Feb 15;45(2):325–333. doi: 10.1002/ijc.2910450220. [DOI] [PubMed] [Google Scholar]
  23. Sklar M. D. The ras oncogenes increase the intrinsic resistance of NIH 3T3 cells to ionizing radiation. Science. 1988 Feb 5;239(4840):645–647. doi: 10.1126/science.3277276. [DOI] [PubMed] [Google Scholar]
  24. TERASIMA T., TOLMACH L. J. Variations in several responses of HeLa cells to x-irradiation during the division cycle. Biophys J. 1963 Jan;3:11–33. doi: 10.1016/s0006-3495(63)86801-0. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Weinert T. A., Hartwell L. H. The RAD9 gene controls the cell cycle response to DNA damage in Saccharomyces cerevisiae. Science. 1988 Jul 15;241(4863):317–322. doi: 10.1126/science.3291120. [DOI] [PubMed] [Google Scholar]
  26. Zietman A. L., Sugiyama E., Ramsay J. R., Silobrcic V., Yeh E. T., Sedlacek R. S., Suit H. D. A comparative study on the xenotransplantability of human solid tumors into mice with different genetic immune deficiencies. Int J Cancer. 1991 Mar 12;47(5):755–759. doi: 10.1002/ijc.2910470522. [DOI] [PubMed] [Google Scholar]

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