Checkpoint inhibitors are so new that not enough patients have received them to allow clinicians to predict who will benefit most. But researchers from the National Cancer Institute, Center for Cancer Institute; Harvard University in Cambridge, Massachusetts; University of Pennsylvania in Philadelphia; and University of Maryland in College Park may have found a clue: A gene expression predictor.
They began by looking at neuroblastoma cases where the immune system seemed to mount “an unprompted, successful immune response” to cancer, causing spontaneous tumor regression. The researchers were able to define gene expression features that separated regressing from nonregressing disease.
The researchers then computed Immuno-PREdictive Scores (IMPRES) for each patient sample. The higher the score, the more likely was spontaneous regression. Analyzing 297 samples from several studies, they found the predictor identified nearly all patients who responded to the inhibitors and more than half of those who did not. “Importantly,” the researchers say, their predictor was accurate across many different melanoma patient datasets.