New finding adds evidence on the role of the microbiota in health: The state of the bacterial flora influences cancer survival
08-19-2019
A study led by a Chilean scientist showed that greater diversity in the body's bacteria drives an increase in life in cases of pancreatic cancer.
Pancreatic cancer is an aggressive disease. In most cases, it does not respond to available treatments and causes thousands of deaths each year.
But, on the other hand, science has advanced in discovering the relationship between bacterial flora - known as microbiota - and health. And precisely cancer is a condition that has been associated with the composition of these microbes.
Now, new research led by Chilean scientist Erick Riquelme, a researcher at the Center for Integrative Biology at the Mayor University, has shown that the diversity of the microbiota plays a role in the survival of patients with pancreatic cancer.
His work, which has just been published in the prestigious magazine Cell, showed several findings.
On the one hand, Riquelme and his team discovered that those who survive more years with the disease have a more diverse microbiota compared to those who survive less.
But the group also showed that it was not just an association by coincidence, since the greater diversity of the organism's bacteria could really be responsible for this greater survival.
Immune system
To reach that result, Riquelme studied 43 patients with pancreatic cancer in the US, in conjunction with researchers from the MD Anderson Center, a Texas-based cancer center.
First, they characterized their microbiota and realized that greater diversity was associated with greater survival.
but, They wanted to verify that it was a causal relationship.
"Then we transfer stools from these patients to mice inoculated with pancreatic cancer tumor cells," explains Riquelme.
And so they discovered that the greater the microbial diversity, there was a greater impact on the immune system, which favored the removal of tumor cells.
"The mice that received depositions of patients with greater microbial diversity and survived developed a smaller tumor, versus mice that received depositions of a patient with lower microbial diversity. This indicated that in the depositions of the first patients there were bacteria that favored immune response against the tumor".
For Riquelme, being able to modify the tumor microbiota of the mice was one of the most important findings.
Potentially, says the researcher, the strategy of transferring stools to a patient also referred to as a fecal transplant to increase the diversity of his microbiota could be used to improve his life expectancy.
This coincides with Jean Michel Butte, digestive surgeon at the FALP Cancer Institute.
"It is very relevant information for the knowledge of other factors that are not taken into account (regarding survival) and that could be important," says the doctor.
And he adds: "It is a good guide to leave, because a new area of research is opened in which there is an association with factors that would be activating the immune system."
However, it is still unclear how the microbiota would act to improve the response to cancer. This is explained by Eduardo Castro, a researcher at the Center for Bioinformatics and Integrative Biology at the U. Andrés Bello.
"It is relevant that this study demonstrates that fecal transplantation of individuals with greater microbial diversity works, although we do not know why," says the scientist, who comments that the results also suggest the importance of caring for microbiota diversity.
A healthy diet such as fiber and dairy intake, as well as avoiding antibiotic abuse, has been associated with a better balance of this.
