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Published on: December 31, 2014

Cells transformed by RNA and DNA tumor viruses produce transforming factors

B Ozanne, T Wheeler, P L Kaplan

    Federation Proceedings
    |November 1, 1982
    PubMed

    Insights

    RNA tumor viruses and DNA tumor viruses produce transforming factors (TFs) that induce cell transformation. Tumor cells show increased responsiveness to these growth factors, suggesting a key role in cancer development.

    Area of Science:

    • Oncology
    • Virology
    • Cell Biology

    Background:

    • RNA tumor viruses like Kirsten murine sarcoma virus (KiMSV) produce transforming factors (TFs).
    • These TFs are similar to sarcoma growth factor (SGF) from Moloney murine sarcoma virus-transformed cells.
    • TF production is linked to a functional viral genome in KiMSV-transformed cells.

    Purpose of the Study:

    • To investigate TF production by DNA tumor viruses.
    • To determine if TFs play a role in anchorage independence.
    • To explore variations in cellular sensitivity to TFs.

    Main Methods:

    • Assaying transforming factor (TF) production from virus-transformed cells.
    • Assessing the effect of TFs on normal Rat-1 cells for anchorage independence.
    • Comparing TFs from different viral sources (RNA vs. DNA tumor viruses).

    Main Results:

    • KiMSV-transformed cells produce TFs that induce a transformed phenotype in normal cells.
    • Simian virus 40 (SV40) and polyoma virus-transformed cells produce factors rendering Rat-1 cells anchorage independent.
    • The SV40-induced TF is distinct from the KiMSV-induced TF.
    • Cellular sensitivity to TFs varies, with tumor cells exhibiting heightened responsiveness.

    Conclusions:

    • Transforming factors (TFs) are produced by both RNA and DNA tumor viruses.
    • TFs play a crucial role in inducing the transformed phenotype and anchorage independence.
    • Increased cellular responsiveness to TFs may contribute to tumor cell growth and malignancy.

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