The immune cells inside tumors hint at a new way to treat cancers
T-cells are being trained to recognize cancer cells inside the immune system, known as “outposts”. Sometimes the immune system has the ability to destroy cancer. More research now shows discovery of tiny clumps of immune tissue forming inside tumors.
Immune system response
These immune outposts, seem to do a good job on improving cancer survival in cancer patients. They can be turned into a new treatment if they are emerged and used artificially. We already know that the immune system responds well to cancer. Researchers apply drugs to test this response, but only a handful of people are responding well to the treatment.
Haydn Kissick at Emory University School of Medicine in Atlanta, Georgia, and his research team examined tumors taken out from about 150 people with the cancers located in the kidneys, bladder, or prostate. A proportion of T-cells, the immune cells that fight tumors, are within growths ranging from 0.002 per cent to over 20% of the total number of cells.
Moreover, T-cells weren’t dispersed within the tumor, but inside outposts in a crowded manner, which were about a tenth of a millimeter across and seen near tiny blood vessels going into the tumors. Outposts also had immature T-cells called stem-like cells, developing a constant supply of new immune cells. As T-cells are dying continually, they keep coming out with stem-like cells.
Indeed, outposts have a second kind of immune cell picking up and showing cancer molecules on the surface, linking them to T-cells as something that has to be attacked. Outposts are mimicking as lymph nodes, but at the location where the fight is happening, compared to ground zero.
In fact, lymph nodes fight anything harmful such as bacteria – or cancer cells by detecting molecules on the surface. Researchers already knew that T-cells inside tumors existed, but there are also stem-like cells. Stem cells have places where they are safe and sound. There was never a need to pinpoint them in an anatomic manner.
Furthermore, outposts have not stopped from growing; some were 10 centimeters across. After patients had their primary tumor removed, those with more outposts were less likely to have regrowth of secondary tumors. Besides, these T-cells had been trained to recognize cancer while inside outposts. When outposts are inside a tumor, you have more control over the disease.
Researchers are now looking to see if some tumors give off chemicals causing outposts to break down. When neutralizing happens, they can show up again.
Tertiary lymphoid structures, another potentially cancer causing structure, is usually found around the outside of tumors and has mainly B-cells, which make antibodies but cannot destroy cells.
What is more, some research groups have been trying to make scaffolds out of algae. They can be seeded with immune cells and placed inside, or next to a tumor. When you get that these structures are necessary to survive, we can manipulate them or get them to grow.