Home Cellular science New findings on bacteria that increase pancreatic cancer risk

New findings on bacteria that increase pancreatic cancer risk



Bacteria in the digestive system appear to have the potential to cause damage to pancreatic cells, increasing the risk of malignant tumors. For the first time, live bacteria from cystic pancreatic lesions, precursors of pancreatic cancer, have been analyzed by researchers at the Karolinska Institute in Sweden. The study, published in the journal Gut Microbes, may lead to prophylactic interventions using local antibiotics.

Pancreatic cancer is one of the most aggressive and deadly forms of cancer. Because it can have vague symptoms, if any, in its early stages, it is usually discovered late, by which time it has spread. Therefore, at the time of diagnosis, the disease has become terminal in the majority of patients. As it stands, pancreatic cancer will soon go away, as breast cancer is the third leading cause of cancer death in the EU.

Cystic lesions, including intracanal mucinous papillary neoplasms (IPMN), of the pancreas are common. Because they are known to be the precursors of pancreatic cancer, many patients require regular check-ups throughout their lives, and a few may require surgery as well. It would be interesting for the individual and for health care to know more about the carcinogenic risk factors. The link between IPMN and pancreatic cancer is not yet fully understood, but previous studies from Karolinska Institutet and elsewhere indicate that the presence of oral bacteria in the pancreas could be a measure of the severity of IPMN lesions.

Researchers at the Karolinska Institutet have now relied on their previous results. Using modern culture methods and a new proteomic technique, they were able to capture living pancreatic bacteria for study in the laboratory. In this new study, they analyzed cystic fluid from 29 patients operated on for cystic pancreatic tumors between 2018 and 2019. Their results showed an overrepresentation of gammaproteobacteria and another class of bacteria called bacilli. These bacteria normally reside in the digestive tract and have already been shown to promote resistance to anticancer drugs by interfering with the effect of gemcitabine, a cytostatic drug used in the treatment of pancreatic cancer. The study showed that these bacteria were present in IPMN and cultivable in 24% of cases.

Upon further laboratory study, the researchers found that many of these bacteria could infect and even hide in pancreatic cells, with adverse consequences. “Certain bacteria could cause double-stranded DNA breakage which is considered the first step in cell damage and cancer,” explains Margaret Sallberg Chen, professor in the department of dentistry at the Karolinska Institutet. “We also found that antibiotics can prevent DNA damage. Our results not only confirm that bacteria play an important role in the development of cancer, but they also shed light on new ways of attacking the process.”

The question of how bacteria from the digestive tract enter the pancreas and then hide in its cells remains unanswered. “Under normal circumstances, the duct from the intestines to the pancreas is closed, but in the presence of inflammation or injury, bacteria may be able to pass through,” says Volkan Ozenci, senior consultant and associate professor in the Department of Medicine of laboratory, Karolinska Institut. “Bacteria have probably migrated from the oral cavity and the gastrointestinal tract to the pancreas through this duct. Some bacteria can also hide in human cells, such as white blood cells, and travel to the pancreas for help. of these cells.

The group says their findings have potential clinical applications. “It would, for example, be relevant to be able to screen patients with IPMN for this type of bacteria,” says co-first author of the study, Dr Asif Halimi, surgeon and doctoral student in the Department of Clinical Sciences, Intervention and technology, Karolinska Institutet. “We discussed the possibility of introducing topical antibiotic therapy in conjunction with, for example, an endoscopic examination or treatment. This would reduce the risk of bacterial infection and prevent future problems.”

Researchers are now examining whether the DNA damage requires the physical bacteria or the metabolites of the bacteria. They also map the sources of bacteria in the gastrointestinal tract and make comparisons with bacteria found in the mouth. (ANI)

(This story was not edited by Devdiscourse staff and is auto-generated from a syndicated feed.)