A New Approach to Making CAR T Cells Effective Against Solid Cancers

In recent years, a development regarded as revolutionary in cancer treatment has been CAR T-cell therapy, which has achieved major successes particularly in hematological (blood-related) cancers. However, this innovative treatment has not yet shown comparable effectiveness against solid tumors arising in organs and tissues.

Solid tumors have heterogeneous structures, complex tumor microenvironments and immunosuppressive characteristics. These features make them one of the biggest obstacles facing CAR T-cell therapy and other cellular treatments.

This article examines a new strategy that could make CAR T-cell therapy more effective against solid cancers. Alongside the promise of this emerging approach, we explore the challenges in this field and how they might be overcome.

Taking Modified CAR T Cells a Step Further

In laboratory research led by Professor Li Tang and his team at the Institute of Bioengineering of Switzerland's École Polytechnique Fédérale de Lausanne, an innovative CAR T-cell treatment for solid cancers achieved important results, consistently eliminating tumors in mouse models.

Meanwhile, disease regression was observed in all 11 patients receiving the treatment in ongoing human clinical trials. These notable findings were reported in Nature Biotechnology . The study offers promising signs of the treatment's long-term effectiveness. Its manufacturing process may also be faster and less expensive than current methods. These findings further enhance the potential of CAR T-cell therapies for solid cancers and contribute importantly to progress in the field.

CAR T-cell treatment involves tailoring T cells to target and destroy particular cancer cells.

Unlike conventional treatments, these modified T cells are equipped with chimeric antigen receptors (CARs) that allow them to recognize and attach to cancer cells.

Professor Tang says, "We have added another layer to CAR T-cell treatment, bioengineering a more robust, supercharged immune cell that is particularly efficient at targeting and destroying tumor cells."

Leman Biotech, a startup founded by Tang and coauthor Yugang Guo, aims to commercialize the treatment.

The company has secured substantial financial backing in its initial fundraising rounds.

Professor Li Tang's pioneering research adds another dimension to this innovative approach.

Although conventional CAR T cells are effective in hematological cancers, they encounter difficulties in solid tumors: the immune cells become exhausted and ultimately fail to eliminate the cancer completely.

What Makes the New Approach Different?

Professor Tang's research has developed modified CAR T cells that secrete IL-10 , representing an important innovation in cancer treatment. These T cells use IL-10, a molecule that normally suppresses the immune system, to protect and strengthen themselves in the difficult tumor environment. In other words, they are engineered to produce their own "medicine" to survive and remain effective within tumors.

Interestingly, IL-10, generally known for suppressing immune responses, plays the opposite role in Tang's study. It strengthens CAR T-cell metabolism, enabling the cells to fight tumors more effectively. This "metabolically armored" treatment acts rapidly on existing tumors and helps prevent future tumors.

In mouse experiments, reinjected tumor cells failed to form new malignant tumors. This suggests that the treatment provides not only an immediate effect but also lasting protection. The modified immune cells appear to remain alert and ready to respond to cancer cells, effectively neutralizing renewed threats.

Tang says, "The results in my laboratory are extremely exciting. We are convinced this technology has the potential to save lives, as it has done for the 11 patients enrolled in our trial so far."

Although existing CAR T-cell therapy has proved effective and several treatments are available for leukemia and other hematological cancers, it is very expensive: one treatment costs more than 500 thousand dollars. This future approach, by contrast, could significantly reduce costs because only five percent of the conventional dose is needed for complete recovery. Much of the cost comes from producing relatively large quantities of modified T cells in expensive laboratory facilities.

Tang concludes, "A small amount of blood from a patient could provide enough cells to prepare CAR T-cell therapy with our technology. They could be injected back into the patient the next day. It will be significantly less expensive and much faster to manufacture, ultimately saving more lives." Tang's team and Leman Biotech are currently working toward this goal.