Heidi Ledford in Nature:
Detailed maps of the immune cells that surround tumours could suggest fresh therapeutic targets, point out biological markers that can be used to select the patients most likely to respond to a given therapy, and offer insights into the best time to start administering that treatment, according to two studies released on 4 May.
…One team, led by systems biologist Bernd Bodenmiller of the University of Zurich in Switzerland, mapped the immune response to a form of kidney cancer called clear cell renal cell carcinoma2. It focused on two kinds of immune cell, T cells and macrophages. Both can either mount or suppress an immune attack on a tumour, depending on the state that they are in and the proteins they express. Bodenmiller and his colleagues examined samples from 73 people with kidney cancer along with 5 samples of healthy tissue. They analysed 3.5 million cells for the expression of 29 proteins used to characterize macrophages, and 23 to characterize T cells. The results showed that populations of those T cells and macrophages are more varied than previously thought. The team also found that patients who had a particular combination of T cells and macrophages also tended to have fast-progressing cancers. The data show that the current practice of looking at only one or two proteins to infer the state of a T cell or macrophage misses important information, says Kai Wucherpfennig, an immunologist at the Dana–Farber Cancer Institute. “It’s very unlikely that a single marker is sufficient,” he says.
Another study, led by oncologist Miriam Merad of the Icahn School of Medicine at Mount Sinai in New York City, created an atlas of immune cells associated with early-stage lung cancer1. The team compared normal lung tissue and blood with tumour tissue, and found that the young tumours had already begun to alter the immune cells in their neighbourhood. This is a sign that cancer therapies that target the immune system need not be reserved for advanced stages of the disease, says Merad. “It suggests that already, we could act,” she says. “We don’t have to wait until the tumour has spread.”