Inside a small lab at Tampere University, a tiny bit of a real patient's lung cancer lives on a glass chip, complete with its own miniature blood vessels. Researchers built this "cancer-on-a-chip" from a patient's own cells to watch, up close, how a new drug pairing attacks the disease. What they saw could one day change how lung cancer is treated.
Lung cancer is the most common cancer in the world and the leading cause of cancer deaths. It is also stubborn: patients treated with targeted drugs often build up resistance, and the disease comes back. That is why scientists from Tampere University, the University of Helsinki, Harvard University, and the Dana-Farber Cancer Institute teamed up to test a fresh idea: pairing two different drugs so they work together.
The first drug, HER3-DXd, is an antibody-drug conjugate — a sort of guided missile that latches onto a protein on cancer cells and delivers a poison straight to them. The second, olaparib, belongs to a class of drugs called PARP inhibitors, which block a cancer cell's ability to repair its own DNA. On their own, each drug does some harm. Together, the research found, they are far more powerful.
The combination stacks DNA damage on cancer cells beyond anything they can fix, pushing them into a state called apoptosis — essentially, programmed cell death. In the lab, the combo slowed tumor growth and extended the lives of laboratory animals. And it worked against cancers carrying two different genetic mutations, known as EGFR and KRAS, which matter because these are common drivers of non-small cell lung cancer, the most frequent form of the disease.
But the treatment did something even more surprising: it woke up the body's own defenses. The drug pairing activated a signaling pathway called cGAS-STING, which sounds a biological alarm that triggers the innate immune response. It also boosted natural killer cells — a type of white blood cell — helping them destroy cancer cells more effectively. So the therapy attacks tumors from two directions at once.
The finding offers hope for patients who get little benefit from existing targeted therapies or whose tumors have grown resistant. Senior research fellow Heidi Haikala of Tampere University and the University of Helsinki highlights a crucial twist: the treatment worked across several genetically distinct lung cancers and did not depend on any one mutation. In fact, she suggests, the HER3 protein could eventually serve as a biomarker to identify which patients are most likely to benefit.
Because the HER3 protein also appears in many other solid-tumor cancers, this approach could reach far beyond lung cancer. The results, published in the journal Cell Reports Medicine, lay a strong foundation for clinical trials in humans. From a chip in a Finnish lab to a possible future therapy — the road ahead is long, but it just got brighter.