8th November 2013
Small RNA molecule in the blood could help diagnose pancreatic cancer
An Indiana University cancer researcher has demonstrated that a particular molecule is present in the blood of most pancreatic cancer patients, suggesting it could someday be a diagnostic marker for the disease.
In research published by the journal Oncogene, Dr. Murray Korc shows that an RNA molecule – microRNA-10b, or miR-10b – is present at high levels in the blood of most pancreatic cancer patients. Consequently, miR-10b could serve as a diagnostic marker, as well as helping physicians to determine the disease's aggressiveness.
Such a marker would be a significant advance against pancreatic cancer, as current treatments typically only extend a person's life for six to 10 weeks. Pancreatic cancer is difficult to detect and diagnose, because there are no noticeable signs or symptoms in the early stages – and because the pancreas is hidden behind other organs such as the stomach, small intestine, liver, gallbladder, spleen and bile ducts.
Dr. Korc and colleagues made the discovery after studying biopsies of people with pancreatic cancer. Korc demonstrated that miR-10b will promote the invasion and growth of pancreatic cancer cells by modulating signaling and gene expression. In particular, the miR-10b facilitates abnormal signaling by allowing the epidermal growth factor receptor, a protein made by many cells in the body and by some types of tumors, to be more efficient. Therefore, the cancer grows and spreads.
Dr. Korc likened the presence of miR-10b to a souped-up car that is more like a tank because of the enhancements. So, for those people with miR-10b, their pancreatic cancer is especially aggressive. And pancreatic cancer is already an aggressive disease without that molecule.
Pancreatic cancer is notorious for its low survival rate (see "When will cancer be cured?"). Only 6 percent of people with the disease live more than five years after diagnosis. According to the National Cancer Institute, there will be an estimated 45,220 new cases and 38,460 deaths from the disease in 2013.
Those patients with high levels of miR-10b resist chemotherapy more and their disease returns sooner after treatment than those without the molecule, Dr. Korc added. More research is needed, he said, as these findings are preliminary.
Dr. Korc was named the inaugural Myles Brand Professor of Cancer Research in October 2011. He is also director of the Center for Pancreatic Cancer Research. His work is focussed on aberrant growth-factor signaling in pancreatic cancer and genetic mouse models of pancreatic cancer, with the goal of designing novel therapeutic strategies. He has published over 270 peer-reviewed manuscripts and is internationally recognised for his research into pancreatic cancer.