Related Experiment Video
Updated: Jul 31, 2026
Establishment and Propagation of Human Retinoblastoma Tumors in Immune Deficient Mice
Published on: August 4, 2011
Instability of v-src sequences in nonhuman primate tumors cultured in vitro
Abstract:
We have analyzed the DNA of marmoset tumors induced and marmoset cells transformed by Rous sarcoma virus (RSV) and derivative viruses of various types. Southern blot hybridization was used to determine the presence of v-src gene sequences. We failed to detect v-src DNA in high-passage cells derived from marmoset tumors induced in vivo or from marmoset cell lines transformed in vitro. The inability to detect src sequences was not related to selection of revertants in culture, since all cell lines retained transformed morphology and cells transformed in vitro retained the ability to induce sarcomas after transplantation into adult allogeneic marmosets. By contrast, we detected integrated proviruses in cells analyzed 32 to 60 days after in vitro transformation. The proviral sequences appeared to be identical to the transforming virus but were apparently unstable and continued to transpose.
Insights
Researchers found Rous sarcoma virus (RSV) v-src DNA was absent in marmoset tumors and transformed cells, despite retained tumor-inducing ability. Proviruses were detected but unstable, suggesting complex viral integration dynamics.
Area of Science:
- Virology
- Oncology
- Molecular Biology
Background:
- Rous sarcoma virus (RSV) is a retrovirus known to cause tumors.
- Understanding the viral genetic mechanisms in tumor formation is crucial for cancer research.
Purpose of the Study:
- To investigate the presence and stability of v-src gene sequences in marmoset tumors and transformed cells induced by RSV.
- To determine if the absence of detectable v-src DNA is due to reversion or other factors.
Main Methods:
- Analysis of marmoset tumor DNA and transformed cell DNA.
- Southern blot hybridization to detect v-src gene sequences.
- Transplantation of transformed cells into allogeneic marmosets to assess tumorigenicity.
Main Results:
- v-src DNA sequences were not detected in high-passage marmoset tumors or transformed cell lines.
- Transformed cell lines maintained tumorigenic potential and transformed morphology, ruling out reversion.
- Integrated proviruses were detected in cells early after in vitro transformation, but these sequences were unstable and appeared to transpose.
Conclusions:
- The absence of detectable v-src DNA in established tumors and cell lines suggests a loss or modification of these sequences over time.
- Unstable and transposing proviruses may play a role in the long-term oncogenic process initiated by RSV.
- Further research is needed to elucidate the precise mechanisms of RSV-induced tumorigenesis and viral DNA dynamics.
