Inside bone marrow’s secret: Taurine and tumour growth

A preclinical research showing scientists are a step closer to finding new ways to target leukaemia, one of the most aggressive blood cancers, is a promising development indeed. The scientific study identified taurine, which is made naturally in the body and consumed through some foods, as a key regulator of myeloid cancers such as leukaemia, according to a paper published in the journal Nature. The Wilmot Cancer Institute investigators at the University of Rochester were able to block the growth of leukaemia in mouse models and in human leukaemia cell samples by using genetic tools to prevent taurine from entering cancer cells.
Led by Jeevisha Bajaj, PhD, the research team discovered that taurine is produced by a subset of normal cells in the bone marrow microenvironment, the tissue inside bones where myeloid cancers begin and expand. Leukaemia cells are unable to make taurine themselves, so they rely on a taurine transporter (encoded by the SLC6A6 gene) to grab taurine from the bone marrow environment and deliver it to the cancer cells. The discovery occurred as scientists were mapping what happens within the bone marrow and its ecosystem—a long-time focus among Wilmot researchers, who have advanced the science around the microenvironment with the goal of improving blood cancer treatments.
“We are very excited about these studies because they demonstrate that targeting uptake by myeloid leukaemia cells may be a possible new avenue for treatment of these aggressive diseases,” said Bajaj, an assistant professor in the Department of Biomedical Genetics and a member of Wilmot’s Cancer Microenvironment research programme. Researchers also discovered that as leukaemia cells drink up taurine, it promotes glycolysis (a breakdown of glucose to produce energy) to feed cancer growth. Prior to this, the authors said, it was not known that taurine might have a cancer-promoting role.
Leukaemia has several subtypes and survival rates vary. This study finds that taurine transporter expression is essential for the growth of multiple subtypes including acute myeloid leukaemia (AML), chronic myeloid leukaemia (CML), and myelodysplastic syndromes (MDS), which all originate from blood stem cells in the bone marrow. Future studies will investigate signals from the microenvironment that promote the transition of MDS, a precursor to leukaemia, to acute leukaemia.
Taurine, the non-essential amino acid is not only found naturally in the bone marrow, but also in the brain, heart, and muscles. Foods such as meats, fish, and eggs, contain taurine. It is also a key ingredient in some energy drinks and protein powders and anecdotally has been used by cancer patients. It’s a hot area of research that’s still developing — and where context matters, Bajaj said. Last year, for example, a research article in the journal Cell, showed results of a taurine investigation into gastric cancers and found that supplements could possibly benefit some patients by boosting the immune system.
Jane Liesveld, MD, a Wilmot oncologist who treats people with leukaemia and co-authored the Nature paper, noted that scientists still have a lot to learn about how leukaemia cells are reprogrammed and draw energy to thrive and resist treatments. “Dr Bajaj’s work shows that local levels of taurine in bone marrow may enhance leukaemia growth, suggesting caution in use of high-dose taurine supplementation,” Liesveld said.
“Metabolic reprogramming is a hallmark of cancer, and we are at the very beginning of understanding metabolic effects on leukaemia cells,” she added. “The prior focus has been on genetic changes, but the focus is expanding to understanding how leukaemia cells are able to hijack various metabolic pathways for their own survival.”
In conclusion, the Wilmot team states in its Nature paper: “Since taurine is a common ingredient in energy drinks and is often provided as a supplement to mitigate the side effects of chemotherapy, our work suggests that it may be of interest to carefully consider the benefits of supplemental taurine in leukaemia patients.” Future studies should investigate levels of taurine in people with leukaemia, Bajaj said. But most importantly: “Our current data suggest that it would be helpful to develop stable and effective ways to block taurine from entering leukaemia cells,” she added.