Hydrogen Gas Boosts Cancer Immunotherapy and Extends Patient Survival
- Authors
- Junji Akagi
- Journal
- Cancer and Chemotherapy
- Year
- 2018
- Study Type
- Human
- Outcome
- Positive
- Peer Reviewed
- Yes
- Country
- Japan
- Health Condition
- Colorectal Cancer
- Body System
- Immune System
TL;DR
Breathing hydrogen gas may improve the survival of advanced colorectal cancer patients by decreasing the number of exhausted immune cells in their blood.
Key Finding
Hydrogen gas treatment reduced the proportion of exhausted immune cells (PD-1+ CD8+ T cells) in nearly two-thirds of advanced colorectal cancer patients, and when combined with nivolumab immunotherapy, patients experienced significantly longer survival compared to nivolumab alone.
Summary
Researchers studied whether hydrogen gas could help the immune systems of 55 advanced colorectal cancer patients fight their cancer. They focused on a specific type of immune cell (CD8+ T cells) that displays a marker called PD-1, which is associated with poor outcomes in cancer patients. After hydrogen gas treatment, about 64% of patients showed a reduction in these problematic immune cells, and when combined with an immunotherapy drug called nivolumab, patients lived longer than those receiving nivolumab alone.
Practical Takeaway
This early human study suggests hydrogen gas may enhance cancer immunotherapy by improving immune cell function, but the findings are preliminary and limited to one cancer type. The study lacked a control group receiving no hydrogen treatment, making it difficult to determine how much benefit came from hydrogen gas alone versus the combination with nivolumab. More rigorous research with larger patient groups and proper control comparisons would be needed before drawing firm conclusions about hydrogen gas as a cancer treatment.
Abstract
It has been reported that PD-1-expressing CD8+ T cells in the peripheral blood of cancer patients are associated with poor cancer prognosis. In addition, these cells are in a state of energy shortage caused by mitochondrial dysfunction with a low level of PGC-1a. Recently, hydrogen gas was reported to activate PGC-1a, leading to the enhancement of mitochondrial activity. In the present study, we investigated whether hydrogen gas influences the proportion of PD-1+ CD8+ T cells in the peripheral blood of 55 Stage IV colorectal carcinoma patients. We found that the proportion of terminal PD-1+ CD8+ T cells was an independent factor for poor prognosis. We also found that the proportion of terminal PD-1+ CD8+ T cells was reduced in 35 out of 55 patients(63.6%)and was increased in 39 out of 55 patients(70.9%)after treatment with hydrogen gas. The ratio of the terminal PD-1+ CD8+ T cells after hydrogen gas treatment to that before hydrogen gas treatment(terminal PD-1+ CD8+ T cell ratio)was found to be an independent factor predicting PFS and OS. Out of another 26 patients treated with nivolumab, 14 patients treated with a combined therapy of hydrogen gas and nivolumab showed a significantly longer OS than the remaining 12 patients who were treated with nivolumab alone. These results suggest that hydrogen gas improves the prognosis of cancer patients by reducing the proportion of terminal PD-1+ CD8+ T cells.