Key Takeaways
- CRISPR-edited T cells lasted up to 9 months, but tumor reduction was not observed.
- No major side effects, but cancer remained unchanged in two patients.
- Larger trials needed to confirm benefits and assess risks.
Promising discovery in the treatment of cancer
Scientists from the University of Pennsylvania and Penn’s Abramson Cancer Center showed that immune cells modified by CRISPR-Cas9 the so-called “genetic scissors” have a sustained effect on fighting cancer in the body.
The modification of immune cells with the CRISPR-Cas9 technique gives new hope to cancer treatment. According to research published in Science, CRISPR-modified T cells survived in the body for up to nine months, but their impact on tumors remains unproven. Until now, other techniques of genetic manipulation of immune cells have only been effective as a cancer weapon for less than a week.
What is this new approach?
One way to fight cancer is to extract T cells (white blood cells that attack abnormal cells growing in the body) from the patient and amplify their effect through genetic manipulation before they are reinjected into the patient. These altered cells then become stronger and can prove effective against cancer cells.
Longer-acting than CAR-T cells
This technique is used for CAR T cells, T lymphocytes, which are genetically engineered to recognize cancer antigens that are only present on the surface of cancer cells. The T lymphocytes, which have become CAR-T cells, then play their role and destroy the diseased cells by binding to their target cells. The limit of these CAR T cells is the risk that, depending on the dose or size of the target tumor, they will act against other cells in the body and trigger a dangerous immune chain reaction for patients already weakened by the disease.
The method used enables the modified immune cells to achieve a much more balanced effect against cancer, and is based on another technique for manipulating T cells – the CRISPR-Cas9 system. These “genetic scissors” edited the DNA of T-cells in three areas: The first two “edits” of their DNA allow natural receptors on these cells to be replaced by more efficient ones, while the third removes the T-cell receptor that would allow cancer cells to counteract their immune response. T cells modified by CRISPR-R Cas9, therefore, have a stronger weapon against cancer cells and an “armor” to protect them from a counter-attack. “This is the first confirmation of the ability of CRISPR-Cas9 technology to address multiple genes simultaneously in humans and illustrates the potential of this technology to treat many diseases that were previously incurable,” said Dr. Carl June, a renowned immunotherapy researcher, and oncologist, the lead author of the study.
Demonstrating treatment safety
This new cancer arsenal has been tested in a clinical trial on three patients aged 60 years with advanced cancer, two with myeloma, and one with sarcoma. The first lesson was that none of them experienced any side effects of this new treatment. While no tumor shrinkage was observed, two patients had stable disease, while the third experienced disease progression. However, the condition of the third patient continued to deteriorate. Still, their work has made it possible to ensure the safety of the treatment and its feasibility in humans, which is a prerequisite for other studies on the effectiveness of CRISPR-Cas9 in modifying T lymphocytes in various types of more or less advanced cancers.
Related Reading:
Herpes Could Finally Be Cured With CRISPR According to Study
CRISPR Prevents Liver Disease In Mice Before Birth
FAQ: Promising Discovery in the Treatment of Cancer
1. What is CRISPR-Cas9, and how does it help fight cancer?
CRISPR-Cas9 is a gene-editing tool that modifies immune cells (T cells) to enhance their ability to attack cancer cells.
2. How is this different from CAR-T cell therapy?
Unlike CAR-T cells, which can trigger dangerous immune reactions, CRISPR-edited T cells provide a more balanced and sustained response against cancer.
3. How long do CRISPR-modified T cells last in the body?
They remained active for at least nine months, significantly longer than previous genetic modifications that lasted only a week.
4. What specific changes are made to T cells using CRISPR?
CRISPR edits T cells in three ways:
- Replacing natural receptors with stronger ones.
- Removing the receptor that cancer cells use to block the immune response.
5. Have these modified T cells been tested in humans?
Yes, a clinical trial on three patients with advanced cancer demonstrated that the treatment is safe.
6. Did the treatment cure any patients?
No, but two patients saw their disease stabilize, while the third continued to decline.
7. Are there any side effects?
No major side effects were observed in the small study, suggesting a good safety profile.
8. What are the next steps for this treatment?
Larger clinical trials are needed to evaluate effectiveness in different cancer types and refine the technique.
9. Could this method be used for other diseases?
Yes, researchers believe CRISPR-Cas9 could be used to treat other previously incurable diseases.
10. Where was this study conducted?
The research was carried out by scientists from the University of Pennsylvania and Penn’s Abramson Cancer Center.
References
Stadtmauer, E. A., Fraietta, J. A., Davis, M. M., Cohen, A. D., Weber, K. L., Lancaster, E., Mangan, P. A., Kulikovskaya, I., Gupta, M., Chen, F., Tian, L., Gonzalez, V. E., Xu, J., Jung, I. Y., Melenhorst, J. J., Plesa, G., Shea, J., Matlawski, T., Cervini, A., … June, C. H. (2020). CRISPR-engineered T cells in patients with refractory cancer. Science, 367(6481), eaba7365. https://doi.org/10.1126/science.aba7365
Penn Medicine. (2020, February 6). CRISPR-edited immune cells can survive and thrive after infusion into cancer patients: New data on first-in-U.S. trial sheds new light on success of gene editing and cell function. Penn Medicine. https://www.pennmedicine.org/news/news-releases/2020/february/crispr-edited-immune-cells-can-survive-and-thrive-after-infusion-into-cancer-patients
