Hidden Risk Factors for Stomach Cancer Identified 0 10

The risk of stomach cancer can develop long before the first symptoms appear — influenced by age, smoking, genetic changes in the blood, and even bacteria from the oral cavity. This conclusion was reached by scientists from Duke-NUS Medical School and the National University Health System of Singapore (NUHS). The results of the study were published in the journal Cancer Discovery (CD).

The researchers studied over 1,500 samples of intestinal metaplasia — a precancerous condition of the stomach lining — collected from six countries. The analysis showed that even at this stage, mutations associated with the future development of cancer accumulate in the cells. Changes in the ARID1A gene were particularly dangerous, as they were linked to a higher risk of tumors and a worse prognosis. Additionally, the researchers identified a characteristic "signature" of DNA damage associated with oxidative stress — a process that is exacerbated by smoking.

The involvement of blood in this process was also unexpected. In some patients, so-called clonal hematopoiesis — age-related mutations in blood stem cells — was found. It was associated with increased vulnerability to stomach cancer and was more common in older individuals. Moreover, such patients had more bacteria typically found in the oral cavity, particularly Streptococcus, in their stomachs. The scientists suggest that the combination of weakened immune control and chronic inflammation accelerates tissue damage in the stomach.

The authors emphasize that stomach cancer does not develop due to a single factor, but as a result of a long "accumulation of risk." The obtained data may help to more accurately identify individuals at high risk long before the disease manifests and to develop preventive strategies.