Recent scientific breakthroughs reveal how cancer cells evade immune detection, with researchers at NYU Langone Health identifying a transcription factor called HOXD13 that drives melanoma growth and restricts T-cell activity, while independent findings from the National University of Singapore published in Science Immunology point to the RNA helicase DDX6 as another critical suppressor of immune-activating danger signals.
HOXD13 Drives Melanoma Growth and Immune Suppression
According to a study published in Cancer Discovery by researchers from NYU Langone Health and its Perlmutter Cancer Center, a protein known as transcription factor HOXD13 plays a central role in melanoma progression and immune evasion. The research team analyzed tumor samples from more than 200 melanoma patients across the United States, Brazil, and Mexico to map biological pathways linked to tumor survival. The investigation showed that HOXD13 activates biological pathways that increase blood flow to tumors, including vascular endothelial growth factor (VEGF), semaphorin-3A (SEMA3A), and CD73.
In addition, the findings indicated a scarcity of cytotoxic T cells within the circulation of individuals expressing elevated HOXD13, alongside physical obstacles that stopped these essential immune cells from entering the tumor microenvironment. “Our study provides new evidence that transcription factor HOXD13 is a potent driver of melanoma growth and that it suppresses the T cell activity needed to fight the disease,” said study lead investigator Pietro Berico, PhD, a postdoctoral research fellow at the NYU Grossman School of Medicine. When researchers decreased HOXD13 activity in laboratory experiments involving mice and human melanoma cell lines, tumors shrank and more T cells infiltrated the cancerous tissue.
Targeting Adenosine and Angiogenesis Pathways
The mechanism behind HOXD13-driven immune evasion involves the production of adenosine, which acts as a protective shield by slowing down T cells. High HOXD13 activity increases CD73 levels, subsequently raising adenosine concentrations around the tumor microenvironment. Dr. Eva Hernando-Monge, PhD, study senior investigator, professor in the Department of Pathology at the NYU Grossman School of Medicine, and member of the Perlmutter Cancer Center, pointed out that these results highlight the benefit of simultaneously inhibiting both angiogenesis and adenosine-receptor pathways. Clinical trials are already testing drugs that block VEGF or adenosine receptors in combination with immunotherapy, paving the way for targeted treatments in patients with elevated HOXD13 levels.
DDX6 and RNA Editing Mechanisms in Singapore
In parallel research published in Science Immunology, scientists from the Cancer Science Institute of Singapore (CSI Singapore) at the National University of Singapore identified a separate mechanism involved in cancer immune evasion. Led by Associate Professor Polly Chen, the research team discovered that the RNA helicase DDX6 works alongside the RNA-editing enzyme ADAR1 to suppress double-stranded RNA (dsRNA) sensors. Normally, dsRNA acts as a warning signal mimicking viral infections that triggers the innate immune system. By suppressing these signals through DDX6, cancer cells effectively cloak themselves from immune detection.
“Cancer cells are remarkably good at hiding from the immune system. Our study uncovered a previously unknown mechanism that helps them stay hidden,” stated Associate Professor Chen. First author Dr. Larry Ng noted that while traditional models assumed RNA editing simply weakened dsRNA structures, the findings demonstrate that specific RNA editing events can strengthen these immune-triggering molecules. Laboratory experiments showed that removing DDX6 restored immune signaling and slowed tumor growth by rendering cancer cells visible to the body’s defenses.