In time, our bodies have developed effective defense mechanisms that protect us against pathogens and other threats. But what happens when the body is exposed to dangers from inside? This opens the door for genetic mutations that can eventually lead to the formation of tumors.
Researchers from Mainz University Medical Center identified a new signal pathway used by skin cancer cells to avoid detection from the immune system. ICER is the protein-making this possible. Dr. Toszka Bohn, Dr. Steffen Rapp, and Professor Tobias Bopp demonstrated that in the absence of ICER, tumors actually grow less rapidly.
“This tumor acidosis induced Gprotein–coupled receptor-dependent expression of the transcriptional repressor ICER in tumor-associated macrophages that led to their functional polarization toward a non-inflammatory phenotype and promoted tumor growth”, notes their study.
The previously unknown immunoevasion mechanism allows certain immune cells called macrophages to migrate into the tumor and become M2 macrophages. They are usually involved in wound healing processes and the regeneration of damaged tissue, and once transferred, benefit the growth of the tumor.
“We were further able to prove that the immune response to tumors is boosted or, in other words, the growth of cancer is slowed, if we eliminate ICER or interrupt the corresponding signal pathway“.
Results of these trials could significantly change cancer management and treatment. The American Academy of Dermatology projects that there will be almost 180.000 new cases of melanoma just in 2018, and the incidence rate is on the rise.
“The mechanism identified through our work provides new insight into how the immune system can be hampered when it comes to fighting cancer, thus giving us potential options for developing innovative treatment approaches“, concluded Professor Hansjörg Schild in the press release.