It was an unexpected discovery that started with an analysis of more than 1,000 genes. The question: why game-changing cancer immunotherapy treatments work for only a fraction of patients. The analysis shone a light on one that popped up repeatedly in patients and mouse models that did not respond to immune checkpoint therapy: stanniocalcin-1, a glycoprotein whose role in both tumors and immunology is largely unknown. By following the trail from this surprising thread, a University of Michigan Rogel Cancer team uncovered how stanniocalcin-1, or STC1, works inside the cell to block a cellular “eat-me” signal that typically triggers the immune system to produce T cells to fight the tumor. The findings, published in Cancer Cell, provide a potential target to improve immune responses to cancer.