Nat Commun: Immune cell steroids or the activity of the host immune system that helps tumors suppress hosts are expected to help develop new cancer immunotherapy treatments.

August 7, 2020 // -- In a recent study published in the international journal Nature Communications, scientists from the Sanger Institute and other institutions in the United Kingdom found that tumors may be able to evade attacks by the host's immune system by telling immune cells to produce immunosuppressive steroids. Immune T cells from mouse skin and breast tumors secrete steroids, while inhibiting the production of these steroids can reduce the growth of tumors in mice, and studies have shown that removing key steroid-producing genes or using drugs to turn off the expression of the gene can significantly slow the formation or progression of cancer.
Image caption After studying mice, the researchers said the steroid signaling path may contain potential drug targets that could help researchers develop new cancer immunotherapy (although later trials are needed in human bodies) The immune system is so complex that while immune cells protect the body from tumors and infections, certain chemicals produced in the body inhibit the body's immune system function, making it difficult for the body to cope with the challenges of cancer, so researchers urgently need to develop cancer immunotherapy that restores the immune system's activity.
Previous studies have revealed that T-cells are able to produce steroids to lower their activity again after an infection, and researchers want to know if T-cells in tumors behave the same way;
researcher Dr Bidesh Mahata said: 'For the first time in this study, we found that tumor T cells in mice produce immunosuppressive steroids, while T cells from healthy mice do not produce such steroids; Promoting tumors to escape attacks from the immune system and keep progressing, a study that excited researchers, suggests that there may be a way to block the production of steroids to treat cancer, and it is a new hope for cancer research, especially for tumors that can use the technique to suppress anti-tumor immunity.
To test whether steroid production could be turned off, the researchers studied mice with missing key steroid synthesis gene Cyp11a1 in T-cells and found that tumors occurred and progressed in normal wild mice, while in mice with the gene Cyp11a1, tumor growth slowed;
After using mouse models, the researchers found that inhibiting T-cell production of steroids may have a significant impact on tumor growth (significantly reducing tumors), removing key genes or using drugs to inhibit their function or stimulate the body's anti-tumor immunity, suggesting that the path to steroid production may be a real "competitor" that could help researchers find drug targets to develop cancer immunotherapy to help treat cancer patients. Sarah Teichmann,
's lead researcher, said the study offers new hope for the later development of new cancer immunotherapy, although the results come from mice, but preliminary studies from human tissue suggest that the same tumor defenses may also be present in the human body, and that researchers now hope to conduct more in-depth studies to find direct evidence of human cancer, and if this is confirmed, future researchers may be able to target the immunosuppressive path to develop new therapies to help re-open the immune system.
source: Mahata, B., Pramanik, J., van der Weyden, L. et al. Tumors induce de novo steroid biosynthesis in T Cells to immunity. Nat Commun 11, 3588 (2020). doi:10.1038/s41467-020-17339-6.