Researchers at the University of Michigan Medical School have found a group of cells that strongly resemble stem cells in the stomachs of mice. The finding, they say, might help in the analysis of gastric cancer.
The research led by Deborah Gumucio, Ph.D., a U-M developmental biologist, has showed that the group of cells called as 'Gastric Progenitor cells' could give rise to all types of specialized cells needed to form the functional stomach glands that line the lower portion of the stomach, which is "multi-lineage potential" property and is considered a key stem cell property.
"The identification of these progenitor cells will not only aid in our understanding of normal cell turnover in the stomach, but could potentially open some new and exciting doors in our investigation of the origins of gastric cancer," Deborah Gumucio said.
Stem cells are a constant source of new cells and represent an important reservoir for repair of damage to the stomach caused by injury or inflammation.
Also of the gastric cells, stem cells live the longest, which is why it is thought that these are the only cells that live long enough to accumulate the multiple mutations that can cause cancers. "Before this work, we knew that stem cells existed in the stomach, but we had no way to precisely identify them," Gumucio said.
"There were no effective markers or tags that we could use to clearly discriminate the stem or progenitor cells from other cells. Now, for the first time, we have the experimental tools to ask important questions, like, 'Does stomach cancer really arise from mutations in this progenitor cell population'" she said.
Intestinal-type gastric, adenocarcinoma, which is one of the most prevalent type of cancer, progresses through a defined series of steps. Initially, the insult is an inflammatory one, usually through infection by an acid-tolerant bacterium called Helicobacter pylori.
The chronic inflammation then leads to changes in the character of the surrounding stomach cells and ultimately, over several years, to tumours.
"Since gastric cancers often occur in the context of inflammation, we were interested to determine whether these progenitor cells are affected by inflammatory conditions," Xiaotan T Qiao, PhD and a research associate said.
"We were amazed to see that though these cells are normally very quiescent, that is, they don't divide, inflammatory signalling proteins such as interferon gamma provide a potent stimulus for multiplication of these cells," he said.
Gumucio said that gastric progenitor cells are in some ways predisposed to being cancer cells; on the other hand, they could also be important reservoirs for repair of damage caused by injury or inflammation.
"These are probably not the only stem-like cells in the stomach. This must be a subset of such cells, but they certainly represent an interesting subset, given their location in the stomach and their response to inflammation," Qiao said.
The study appears in the journal Gastroenterology.