Latest Cell Therapy Shows Promise Against Solid Tumors

A novel cell therapy, termed HIT cells, is demonstrating significant potential in the fight against solid cancers, offering a new avenue of hope for patients with tumors resistant to current treatments. Research led by Columbia University Irving Medical Center, published in Science on February 26, 2026, reveals that HIT cells—related to CAR-T cell therapy—can eliminate kidney, pancreatic, and ovarian cancers in mice.

The Challenge of Solid Tumors

CAR-T cell therapy has revolutionized the treatment of blood cancers, but its effectiveness against solid tumors has been limited. Solid tumors, accounting for over 85% of all cancers, present unique challenges. Unlike blood cancers where target antigens are abundant and consistent, solid tumors exhibit greater diversity, lacking a single, universally expressed molecule for immune cells to target. Columbia University Medical Center

How HIT Cells Overcome Obstacles

The key innovation lies in the enhanced sensitivity of HIT cells. Researchers discovered that even when cancer cells express low levels of the CD70 protein—often undetectable by conventional methods—HIT cells can still recognize and eliminate them. This is crucial due to the fact that CD70 is found in a significant number of solid tumors. Science.org

“Curing solid tumors is not simple, but this work solves one piece of the puzzle,” says Michel Sadelain, director of the Columbia Initiative in Cell Engineering and Therapy (CICET) and a pioneer in CAR-T therapy. Columbia University Medical Center

CD70: A Promising Target

While CD70 has been considered a potential target for immunotherapy, previous clinical trials in kidney cancer—a type known to express CD70—failed to show significant results. Sadelain’s research reveals that CD70 expression isn’t simply “on” or “off,” but exists on a spectrum, with some cells expressing incredibly low levels. The new, highly sensitive CAR-T therapy developed by the Columbia team can effectively target these cells with minimal CD70 expression. Nature.com

Researchers found that all cells in the analyzed tumors presented the CD70 protein, even if the amount was too low to be detected with current techniques. Science.org

Promising Results in Mice

In experiments, mice with kidney cancer metastases experienced complete remission after a single dose of HIT cells. The researchers believe this is because CD70 is often overexpressed in metastases, particularly in the lungs. Nature.com

Next Steps: Clinical Trials

The research team is now planning to initiate phase I safety trials in humans, focusing initially on patients with glioblastoma, acute myeloid leukemia, ovarian cancer, and pancreatic cancer. Columbia University Medical Center

“We do not expect CD70 to be expressed in all solid tumors, but in more than we think today,” Sadelain stated. Science.org

Potential Risks and Considerations

As with other CAR-T therapies, there is a potential for toxicity, as some immune cells express CD70 temporarily when activated, leading to the possibility of eliminating beneficial immune cells. However, researchers believe the benefits of targeting CD70 outweigh the risks, and clinical trials will be crucial to assess safety and efficacy. Science.org