With any cancer, developing treatments is difficult because cancer cells are an abnormal version of healthy cells. Any drug used to kill cancer cells runs the risk of killing healthy cells during the process. In the case of T cell lymphoma, the healthy cells that are at risk of friendly fire are vital cells of the immune system that are needed to defend the body from infection.
In collaboration with biopharmaceutical company Autolus Ltd, scientists from Cardiff University developed a new approach to treating T cell lymphoma, one that zeroes in on cancerous cells and keeps healthy T cells safe and fully-functioning.
As its name suggests, T cell lymphoma is a cancer the originates in abnormally growing T cells, a population of cells vital to a cell-mediated immune response that specifically targets incoming pathogens. Lymphoma is the most common type of blood cancer, and T cell lymphoma, a rare and usually aggressive cancer, accounts for 15 percent of all non-Hodgkin lymphoma cases in the United States.
"We wouldn't last a week without the essential job our T cells perform by protecting us from infection,” explained Cardiff University’s Andrew Sewell. “The devastating effects of low numbers of just one type of T cell are all too evident in HIV/AIDS.”
The new approach to treating T cell lymphoma is based on the two genes responsibel for creating the T cell receptor, a surface molecule that helps T cells recognize specific pathogens. A T cell is made by either the “C1” gene or the “C2” gene, and because cancer starts with a single cell, a whole tumor is either entirely made up of C1 T cells or of C2 T cells.
So, scientists decided to try and destroy T cells based on whether they were made by the C1 or C2 gene. In theory, they could target C1 T cells to kill C1 cancers while leaving C2 T cells alone, and vice versa. This eliminates the problem faced by scientists in the past looking for T cell lymphoma treatments, where telling the difference between healthy and cancerous T cells was tedious and not always accurate.
“Since T-cells select use of the C1 or C2 gene at random, this remaining half of T-cells are capable of providing immunity to the pathogens we encounter every day,” Sewell explained.
"This study has demonstrated it's possible to kill cancerous T-cells but importantly spare some healthy ones, opening up exciting new treatment possibilities,” said Cancer Research UK’s Dr. Justine Alford. “T cells are a vital part of our immune system and our survival.”
The present study was published in the journal Nature Medicine.