Gene Yang ‘19

Lentiviruses are a group of virus that cause deadly diseases, but these same viruses can be modified into harmless versions used in gene therapy, where the virus is used to transport a desired gene into an organism. Using this technique, scientists from The Institute of Cancer Research in London modified lentiviruses to deliver two genes into the tissue cells of rats. The first gene, SOD2, is helps prevent radiation damage by allowing cells to process a type of byproduct, known as mitochondrial reactive oxygen species, more efficiently. The second gene, CTGF, plays a role in tissue wound repair, and is known to help reduce tissue scarring in radiotherapy.

After SOD2 and CTGF gene therapy, both normal rat tissue cells and cells that underwent gene therapy was given radiotherapy that simulated the level of radiation used in cancer treatment. The scientists found that six months after radiotherapy, tissue cells that had been treated with SOD2 and CTGF shrunk only 15% compared to the 70% found in cells that did not undergo gene therapy. The tumor cells, however, were still affected by radiotherapy, suggesting that targeting healthy tissue cells around the tumor with gene therapy does not protect the tumor from radiation.

Since the SOD2 and CTGF gene help prevent radiation damage using different mechanisms, this also suggests that the effects of these two genes are additive. Additionally, tumors in four out of the five rats treated with gene therapy responded better to radiotherapy, indicating that the SOD2 and CTGF genes may also help increase the effectiveness of radiotherapy on tumor cells. Although the exact reason why this happens is still unknown, this study is a step forward into more efficient radiotherapy techniques in the near future.

References

1. A. Khan, et al., Genetically modified lentiviruses that preserve microvascular function protect against late radiation damage in normal tissues. Science Translational Medicine 10 (2018). doi: http://10.1126/scitranslmed.aar2041.
2. Image retrieved from: https://www.flickr.com/photos/fdaphotos/39151355192