University of Gothenburg logoGastric cancer commonly known as stomach cancer is a malignant tumor in the mucous membrane of the stomach. Patients with this disease are known to be subjected to operation as well as radiotherapy and chemotherapy. One of the key causes of this disease is identified as the stomach ulcer bacterium Helicobacter pylori. A recent study initiated by Sahlgrenska Academy, University of Gothenburg has seemingly discovered the cells in the immune system reacting to Helicobacter pylori.

The authors highlighted that this commonly found bacterium often causes chronic inflammation of the stomach. Moreover, the carriers are reported to be symptom-free. This bacterium is ascertained to lead to stomach ulcers and at times causes the development of stomach cancer. Since the symptoms of this disease are not constant, physicians are unable to identify this disease in the early stages and are therefore incapable to provide better diagnosis at the correct time.

Asa Lindgren, a researcher from the Department of Microbiology and Immunology shared, “We don’t know how the chronic inflammation caused by Helicobacter pylori affects the development of stomach cancer. So it was interesting to study how the immune system behaves towards Helicobacter pylori in the stomach.”

The investigators aimed to understand the way natural killer cells known as NK cells which are a type of immune cell react to Helicobacter pylori. It is claimed that these cells play a major role in the immune system as they identify and kill cells infected by viruses, bacteria and tumor cells also. The authors were apparently able to determine NK cells as of crucial importance in immune defence against Helicobacter pylori.

Asa Lindgren affirmed, “We found that a special type of NK cells was active against the stomach ulcer bacterium. These NK cells produced cytokines, which are the immune system’s signal substances and act as a defence against the intruder.”

Prior analysis have also stated that once the NK cells in tumour tissue are in a high proportion, better prognosis and longer survival for patients with stomach cancer had been detected. This is because of the cells ability to discard the tumor cells. The scientists concluded that if the NK cells are activated they can restrict the development of tumors but when NK-cell activity is reduced it can elevate the risk of developing cancer. The study looks to offer new treatments and early diagnosis for patients with stomach cancer.

The study has been published in a thesis from the Sahlgrenska Academy.