How tumor hypoxia suppresses the immune response
A team of researchers at the at have made headway in determining how the upregulation of adenosine in the hypoxic tumor microenvironment influences cell responses to immunotherapy.
Cells constantly are regulating every aspect of cell growth with complex signaling pathways and checkpoints to ensure everything is working normally. When cells notice something foreign or harmful, such as cancer cells, they activate their to eliminate the harm. Cancer, however, has adapted to override this response, which allows cancer cells to grow into lethal tumors.
Kai Beattie is an undergraduate working under the direction of and at the New England Inflammation and Tissue Protection Institute.
Beattie and colleagues are working to elucidate evolutionary conserved mechanisms of immune evasion and metastatic dissemination exploited by cancerous cells. He will discuss his team’s findings today during a poster presentation at the 2022 ͵͵ and ͵͵ Biology Annual Meeting held in conjunction with the Experimental Biology conference in Philadelphia.
“Studying cancer’s molecular underpinnings is especially intriguing to me because it represents an impossibly difficult biological puzzle that is the ultimate product of Darwinian evolution,” Beattie said. “When we study biochemical pathways enriched in tumors, we are actually beginning to understand ancient mechanisms of survival. Such is the case for hypoxia–adenosinergic signaling and the epithelial–mesenchymal transition.”
Cancer cells override the immune response by changing their surroundings to make the ideal for tumor growth.
Tumor hypoxia is when cancer cells have low oxygen levels because they are consuming oxygen to grow faster than the body can make more oxygen. Just as when we work out, we breathe faster to get more oxygen, when cells grow faster, they need more oxygen.
Tumor hypoxia upregulates the body’s hypoxic response, including increasing the amount of hypoxia-inducible factor 1, or HIF-1, alpha, which in turn produces extracellular . These increased levels of adenosine bind to , called A2AR for short, and suppress the body’s anti-tumor immune , allowing the cancer cells to continue to grow without the immune response getting in the way.Beattie and colleagues are studying the A2AR signaling pathway and how this pathway could be harnessed to enable antitumor responses. Beattie’s research specifically focuses on understanding the mechanism with which HIF-1ɑ increases adenosine levels. Better understanding the link between HIF-1ɑ and adenosine levels will add another potential regulation mechanism for programming the anti-tumor response.
While studying HIF-1ɑ’s mechanism, Beattie discovered adenosine-generating enzymes and changes in adenosine metabolism when hypoxic conditions are induced. Using epithelial murine breast cancer and quasi-mesenchymal carcinoma cells, he and his team found a remarkable difference in adenosinergic enzymes and epithelial–mesenchymal transition transcription factors during hypoxia.
Future work by Beattie and colleagues will focus on validating his findings in 3D cell aggregates that can mimic tissues (spheroids) and in preclinical mouse models, potentially using gene editing methods to establish key proteins involved in anti-hypoxia-HIF-1ɑ-A2AR treatment.
Beattie said the take-home message of his work so far is this: “Hypoxia-dependent signaling within neoplastic contexts represents one of many pathophysiological hallmarks of cancer that are integral to carcinogenesis and development of therapeutic resistance. Our knowledge of these biological capabilities is directly translatable to the development of treatments that, in the case of hypoxia–adenosinergic signaling, enhance anticancer immunity through the liberation of tumor-reactive cytotoxic lymphocytes from immunosuppression.”
Beattie continues to volunteer at the New England Inflammation and Tissue Protection Institute and has begun research at the Broad Institute of MIT and Harvard. He plans to continue exploring cancer biology in preparation to apply for Ph.D. programs with an emphasis on genetics and functional genomics approaches.Kai Beattie will present this research between 12:45 and 2 p.m. Sunday, April 3, in Exhibit/Poster Hall A–B, Pennsylvania Convention Center (Poster Board Number A346) ().
Enjoy reading ASBMB Today?
Become a member to receive the print edition four times a year and the digital edition weekly.
Learn moreGet the latest from ASBMB Today
Enter your email address, and we’ll send you a weekly email with recent articles, interviews and more.
Latest in Science
Science highlights or most popular articles
Guiding grocery carts to shape healthy habits
Robert “Nate” Helsley will receive the Walter A. Shaw Young Investigator in Lipid Research Award at the 2025 ASBMB Annual Meeting, April 12–15 in Chicago.
Quantifying how proteins in microbe and host interact
“To develop better vaccines, we need new methods and a better understanding of the antibody responses that develop in immune individuals,” author Johan Malmström said.
Leading the charge for gender equity
Nicole Woitowich will receive the ASBMB Emerging Leadership Award at the 2025 ASBMB Annual meeting, April 12–15 in Chicago.
CRISPR gene editing: Moving closer to home
With the first medical therapy approved, there’s a lot going on in the genome editing field, including the discovery of CRISPR-like DNA-snippers called Fanzors in an odd menagerie of eukaryotic critters.
Finding a missing piece for neurodegenerative disease research
Ursula Jakob and a team at the University of Michigan have found that the molecule polyphosphate could be what scientists call the “mystery density” inside fibrils associated with Alzheimer’s, Parkinson’s and related conditions.
From the journals: JLR
Enzymes as a therapeutic target for liver disease. Role of AMPK in chronic liver disease Zebrafish as a model for retinal dysfunction. Read about the recent JLR papers on these topics.