Note: Single-source report; awaiting corroboration.
Early findings from a small clinical trial suggest a personalized cellular immunotherapy approach may be effective against metastatic solid tumors, especially in patients with metastatic colorectal cancer who had undergone multiple prior treatments.
Researchers at the National Institutes of Health genetically engineered patients' lymphocytes (white blood cells) to carry receptors that recognize and attack the patients’ own cancer cells. This treatment led to tumor shrinkage in some patients and maintained tumor suppression for up to seven months, according to findings published in Nature Medicine.
Co-lead investigator Steven A. Rosenberg, M.D., Ph.D., of the NIH’s Center for Cancer Research, noted that this approach addresses major challenges in cellular immunotherapies: generating large numbers of T cells specifically targeting cancer cells, and enhancing these modified T cells’ ability to multiply once returned to the patient.
The process began by collecting lymphocytes from patients' tumors and using molecular methods to identify and isolate T-cell receptors that recognize tumor-specific changes. The receptor genes were sequenced and inserted via retrovirus into lymphocytes from the patients’ blood. These genetically modified lymphocytes were expanded to hundreds of millions before being infused back into the patients, where they expressed tumor-specific receptors.
Although this approach shows promise for treating metastatic solid cancers, researchers emphasize that findings are preliminary. Further refinement and testing are needed, including trials in other types of solid tumors.