201008global.jpgHONG KONG, June 4 (Xinhua) — Hong Kong researchers have identified a subset of cancer stem cells responsible for metastasis in human colorectal cancer which can help better predict the prognosis and design a more suitable treatment for patients, according to a study made public by the University of Hong Kong on Friday.

The researchers from the university's medicine school discovered that cancer stem cells with a surface marker CD26, which marks a subset of cancer stem cells with metastatic capacity, are present in all terminal colon cancer cells and all metastatic cancer cells.

Research Assistant Professor of the university's department of medicine Roberta Pang Wen-chi said cancer stem cells, which are responsible for tumor initiation and maintenance, are more resistant to conventional chemotherapy treatments than the more mature cancer cells within the tumor, and therefore, tumor shrinkage after the chemo does not mean all tumor cells are killed.

Even with adequate surgical removal of the primary tumor, distant metastasis develop in more than 50 percent of patients, Pang added.

The study results suggested that patients of early stage colon cancer with CD26+ in their tumors are having a higher chance of cancer recurrence and metastasis.

"Identifying patients with CD26+ cancer stem cells can help design a more intensive treatment for them," said Pang, adding that the identification of the cancer stem cells provides insight into novel strategy to target these stem cells to more effectively treat metastasis in colorectal cancer.

The above results have been published in Cell Stem Cell, the top journal in stem cell research.