
Study finds gut bacterium that raises immune effect to cancer
Scientists said they have found and identified a gut bacterium that can enhance the effectiveness of immunotherapy against cancer.
The researchers, primarily from the National Cancer Center Japan, said they ascertained the detailed mechanism by which the bacterium affects the immune environment around malignant tumors far from the intestines.
They said they expect the bacterium will be applied in clinical research settings in the near future.
The team's findings were published in the British scientific journal Nature on July 15.
Anti-cancer agents known as immune checkpoint inhibitors, including renowned Opdivo, take advantage of killer T cells to attack tumors.
These drugs enhance the immune cells' function while blocking carcinoma's ability to evade the human immune system.
However, only about 20 percent of patients experience long-term therapeutic effects of the immune checkpoint inhibitors.
Earlier studies had revealed that some of the more than 100 trillion bacteria in human intestines can influence how immune checkpoint inhibitors work. But it was unclear which of them were actually useful in the treatment process.
With that in mind, the research team analyzed the excrement of 71 patients with lung and stomach cancer.
The scientists then compared gut bacteria between people for whom immune checkpoint inhibitors are effective and those for whom they are not.
The analysis showed that patients experiencing positive effects had more gut bacteria linked to the Ruminococcaceae family.
The team then pinpointed the specific bacterium strain in the family capable of improving the effectiveness of immune checkpoint inhibitors. The strain was named YB328 and cultured successfully.
As the next step, the scientists carried out an experiment on mice whose intestinal bacteria had been removed in advance.
The combined use of an immune checkpoint inhibitor and YB328 reduced the carcinoma size through the test.
The team also became aware that administering YB328 helped deliver a therapeutic impact even on mice transplanted with feces from patients who had not experienced positive effects from drug treatment.
The researchers explored the way the therapeutic effect of YB328 in the gut reaches the immune system around cancer cells, despite their distance from the intestines.
They found that YB328 activates dendritic cells in the gut that play a leading role in the immune response. This activation enables dendritic cells to travel all the way to cancerous and lymphatic tissues in distant organs, facilitating the function of killer T cells near tumors and thereby bringing about immune effects.
According to the team, YB328 can be considered a safe bacterium, given that it has been confirmed in 20 percent of people worldwide regardless of race or region.
'Administering YB328 may allow immune checkpoint inhibitors to manifest their therapeutic effects even among patients who could otherwise not benefit from them,' said Hiroyoshi Nishikawa, chief of the Division of Cancer Immunology at the National Cancer Center Research Institute.
The team's findings can be found at (https://www.nature.com/articles/s41586-025-09249-8).
(This article was written by Chisato Matsumoto and Ayaka Kibi.)
Hashtags

Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles


Asahi Shimbun
2 days ago
- Asahi Shimbun
Study finds gut bacterium that raises immune effect to cancer
The intestine bacterium strain called YB328 apparently heightens the effectiveness of immune checkpoint inhibitors. (Provided by the National Institute of Advanced Industrial Science and Technology and the National Cancer Center Japan) Scientists said they have found and identified a gut bacterium that can enhance the effectiveness of immunotherapy against cancer. The researchers, primarily from the National Cancer Center Japan, said they ascertained the detailed mechanism by which the bacterium affects the immune environment around malignant tumors far from the intestines. They said they expect the bacterium will be applied in clinical research settings in the near future. The team's findings were published in the British scientific journal Nature on July 15. Anti-cancer agents known as immune checkpoint inhibitors, including renowned Opdivo, take advantage of killer T cells to attack tumors. These drugs enhance the immune cells' function while blocking carcinoma's ability to evade the human immune system. However, only about 20 percent of patients experience long-term therapeutic effects of the immune checkpoint inhibitors. Earlier studies had revealed that some of the more than 100 trillion bacteria in human intestines can influence how immune checkpoint inhibitors work. But it was unclear which of them were actually useful in the treatment process. With that in mind, the research team analyzed the excrement of 71 patients with lung and stomach cancer. The scientists then compared gut bacteria between people for whom immune checkpoint inhibitors are effective and those for whom they are not. The analysis showed that patients experiencing positive effects had more gut bacteria linked to the Ruminococcaceae family. The team then pinpointed the specific bacterium strain in the family capable of improving the effectiveness of immune checkpoint inhibitors. The strain was named YB328 and cultured successfully. As the next step, the scientists carried out an experiment on mice whose intestinal bacteria had been removed in advance. The combined use of an immune checkpoint inhibitor and YB328 reduced the carcinoma size through the test. The team also became aware that administering YB328 helped deliver a therapeutic impact even on mice transplanted with feces from patients who had not experienced positive effects from drug treatment. The researchers explored the way the therapeutic effect of YB328 in the gut reaches the immune system around cancer cells, despite their distance from the intestines. They found that YB328 activates dendritic cells in the gut that play a leading role in the immune response. This activation enables dendritic cells to travel all the way to cancerous and lymphatic tissues in distant organs, facilitating the function of killer T cells near tumors and thereby bringing about immune effects. According to the team, YB328 can be considered a safe bacterium, given that it has been confirmed in 20 percent of people worldwide regardless of race or region. 'Administering YB328 may allow immune checkpoint inhibitors to manifest their therapeutic effects even among patients who could otherwise not benefit from them,' said Hiroyoshi Nishikawa, chief of the Division of Cancer Immunology at the National Cancer Center Research Institute. The team's findings can be found at ( (This article was written by Chisato Matsumoto and Ayaka Kibi.)


Japan Today
4 days ago
- Japan Today
In Darwin's wake: Two-year global conservation voyage sparks hope
By Richard CARTER After a two-year around-the-world ocean voyage inspired by Charles Darwin, scientists and crew sailed home on a historic vessel into Rotterdam on July 31, bearing a warning about climate change -- but also a message of hope. The majestic three-masted Oosterschelde, the last remaining vessel from a fleet of Dutch schooners that criss-crossed the globe in the early 20th century, arrived to a welcome befitting a voyage of more than 40,000 nautical miles (74,000 kilometers). Ceremonially escorted by more than a dozen vessels ranging from tall ships to steamships, all blaring horns, the Oosterschelde received a "water cannon salute" from fire service boats, as hundreds waved and cheered from the banks. Like Darwin in 1831, the Oosterschelde departed the British port of Plymouth in August 2023 to embark on a voyage of discovery that took in the major stops explored during the British naturalist's world-changing mission aboard the HMS Beagle. From the Falkland Islands to the southern tips of Africa, South America and Australia, the trip closely shadowed Darwin's voyage that inspired his groundbreaking theory of natural selection described in "On the Origin of Species". Aboard the Oosterschelde at various points of the voyage were some of the world's best young conservationists, 100 scientists aged 18-25, selected to study a species also observed by Darwin, himself aged 22 at the time of his trip. Giant tortoises, Chilean dolphins, and howler monkeys were just some of the weird and wonderful creatures the young "Darwin Leaders" investigated, tracking changes since their appearance in "Origin of Species" two centuries ago. With "online classrooms" onboard and slick social media output, the mission also hoped to inspire a new generation around the message: "Conservation isn't about what we've lost, it's about protecting what we still have." 'Barely anything left' One of the Darwin Leaders, 23-year-old Lotta Baten, spent a week on the ship and conducted a study into the impact of tourism on forests in Tenerife, Spain. She said only roughly four percent of the forest that Darwin would have seen from the Beagle is still alive today, with much torn down to support the tourism industry. "There's barely anything left, mainly the strips around the coast," the Dutch-German scientist told AFP. She said it was "quite something" to follow in the footsteps of Darwin, but noted that the botanist's legacy is divided, as a European in colonial times. "He basically explored and discovered things that maybe had already been explored and discovered by people at the places themselves. And then he claimed he discovered them," said Baten. Science co-ordinator Rolf Schreuder admitted that "it's not a rosy picture", with habitat loss and climate change all transforming the environment beyond what Darwin would have recognized. "You see the natural world degrading in many places," the 55-year-old told AFP. But Schreuder, like many on board, found the mission inspiring rather than depressing. He ran more than 100 local projects during the trip with people seeking to preserve their landscapes. "We met so many great people that are actually on the ground working on the survival of those species," he said. He found himself inspired too by the young scientists, "full of ideas, full of commitment and determination to really make a difference." Crew member Daan van Roosmalen was a boy of 17 when he set sail on the Oosterschelde. He returned to his native Netherlands having just turned 19. "I've just been to so many places. To the Galapagos Islands, French Polynesia. We went so far away and to then sail back up this river and see the skyline of Rotterdam again is just super special," he told AFP. He said he hoped the round-the-world voyage completed by scientists and crew his age would send a message to his generation. "I think it's very important that we keep inspiring young people to look after our world, because we are going to be the ones taking over," he said. "So to see all these young conservationists putting so much effort in Mother Earth... I think that should inspire more people to also take care of our planet." And what of Darwin, the inspiration behind the mission? "I would say he would have been enthused by his fellow young people taking care of this natural world, which he described so nicely," said Schreuder. "I think he would hop on this boat again and do another tour." © 2025 AFP


Japan Today
5 days ago
- Japan Today
Vaccines hold tantalizing promise in the fight against dementia
By Anand Kumar and Jalees Rehman Over the past two centuries, vaccines have been critical for preventing infectious diseases. The World Health Organization estimates that vaccination prevents between 3 million and 5 million deaths annually from diseases like diphtheria, tetanus, influenza, measles and, more recently, COVID-19. While there has long been broad scientific consensus that vaccines prevent or mitigate the spread of infections, there is new research suggesting that the therapeutic impact might go beyond the benefit of preventing infectious diseases. An April study published in the prominent journal Nature found tantalizing evidence that the herpes zoster – or shingles – vaccine could lower the risk of dementia in the general population by as much as 20%. We are a team of physician scientists with expertise in the clinical and basic science of neurodegenerative disorders and dementia. We believe that this study potentially opens the door to other breakthroughs in understanding and treating dementia and other degenerative disorders of the brain. A role for vaccines in reducing dementia risk? One of the major challenges researchers face when trying to study the effects of vaccines is finding an unvaccinated 'control group' for comparison – a group that is similar to the vaccine group in all respects, save for the fact that they haven't received the active vaccine. That's because it's unethical to assign some patients to the control group and deprive them of vaccine protection against a disease such as shingles. The Nature study took advantage of a policy change in Wales that went into effect in 2013, stating that people born on or after September 2, 1933, were eligible for the herpes zoster vaccination for at least a year, while those born before that cutoff date were not. The vaccine was administered to prevent shingles, a painful condition caused by the same virus that causes chickenpox, which can lie dormant in the body and be reactivated later in life. The researchers used the policy change as a natural laboratory of sorts to study the effect of shingles vaccination on long-term health outcomes. In a statistically sophisticated analysis of health records, the team found that the vaccine reduced the probability of getting dementia by one-fifth over a seven-year period. This means that people who received the shingles vaccine were less likely to develop clinical dementia over the seven-year follow-up period, and women benefited more than men. The study design allowed researchers to compare two groups without actively depriving any one group of access to vaccination. The two groups were also of comparable age and had similar medical comorbidities – meaning similar rates of other medical conditions such as diabetes or high blood pressure. Results from this and other related studies raise the possibility that vaccines may have a broader role in experimental therapeutics outside the realm of infectious diseases. These studies also raise provocative questions about how vaccines work and how our immune system can potentially prevent dementia. How vaccines might be protective One scientific explanation for the reduction of dementia by the herpes zoster vaccine could be the direct protection against the shingles virus, which may play a role in exacerbating dementia. However, there is also the possibility that the vaccine may have conferred protection by activating the immune system and providing 'trained immunity,' in which the immune system is strengthened by repeated exposure to vaccines or viruses. The study did not differentiate between different types of dementia, such as dementia due to Alzheimer's disease or dementia due to stroke. Additionally, researchers cannot draw any definitive conclusions about possible mechanisms for how the vaccines could be protective from an analysis of health records alone. The next step would be a prospective, randomized, double-blind, placebo-controlled study – the 'gold standard' for clinical trials in medicine – to directly examine how the herpes zoster vaccine compares with a placebo in their ability to reduce the risk of dementia over time. Such studies are necessary before any vaccines, as well as other potential therapies, can be recommended for routine clinical use in the prevention of dementia. The challenges of untangling dementia Dementia is a major noncommunicable disease that is a leading cause of death around the world. A January 2025 study provided updated figures on lifetime dementia risk across different subsets of the U.S. population. The researchers estimate that the lifetime risk of dementia after age 55 is 42% – more than double earlier estimates. The dementia risk was 4% by age 75, and 20% by age 85, with the majority of risk occurring after 85. The researchers projected that the number of new cases of dementia in the U.S. would double over the next four decades from approximately 514,000 cases in 2020 to 1 million in 2060. Once considered a disease largely confined to the developed world, the deleterious effects of dementia are now apparent throughout the globe, as life expectancy increases in many formerly developing countries. While there are different forms of dementia with varying clinical manifestations and underlying neurobiology, Alzheimer's disease is the most common. Prospective studies that specifically test how giving a vaccine changes the risk for future dementia may benefit from studying patient populations with specific types of dementia because each version of dementia might require distinct treatments. Unfortunately, for the past two to three decades, the amyloid hypothesis of Alzheimer's disease – which posits that accumulation of a protein called amyloid in the brain contributes to the disorder – dominated the scientific conversation. As a result, most of the efforts in the experimental therapeutics of Alzheimer's disease have focused on drugs that lower the levels of amyloid in the brain. However, results to date have been modest and disappointing. The two recently approved amyloid-lowering therapies have only a minimal impact on slowing the decline, are expensive and have potentially serious side effects. And no drug currently approved by the Food and Drug Administration for clinical use reverses the cognitive decline. Studies based on health records suggest that past exposure to viruses increase the risk of dementia, while routine vaccines, including those against tetanus, diphtheria, pertussis, pneumonia, shingles and others, reduce the risk. Innovation and an open mind There is sometimes a tendency among scientists to cling to older, familiar models of disease and a reluctance to move in more unconventional directions. Yet the process of doing science has a way of teaching researchers like us humility, opening our minds to new information, learning from our mistakes and going where that data takes us in our quest for effective, lifesaving therapies. Vaccines may be one of those paths less traveled. It is an exciting possibility that may open the door to other breakthroughs in understanding and treating degenerative disorders of the brain. Anand Kumar is Professor and Department Head of Psychiatry, University of Illinois Chicago. Jalees Rehman is Department Chair and Professor of Biochemistry and Molecular Genetics, University of Illinois Chicago. The Conversation is an independent and nonprofit source of news, analysis and commentary from academic experts. External Link © The Conversation