(DGIwire) – Pancreatic cancer often has a poor prognosis, even when diagnosed early, according to the Mayo Clinic. This cancer typically spreads rapidly and is seldom detected in its early stages, which is a major reason why it is a leading cause of cancer death. According to the American Cancer Society, about 53,000 Americans will be diagnosed with pancreatic cancer in 2016 and about 42,000 of them will die from this disease.
In April 2016, researchers from the University of Liverpool, working with colleagues around the globe, announced a new explanation for how pancreatic cancer spreads to the liver, according to ScienceDaily. The study focused on the role of the host connective tissues in the pancreas, or stromal cells, as the cancer cells spread to the liver. The study found that stromal cells are critical for efficient metastatic growth of pancreatic cancer cells, and identified a protein named granulin as a key regulator of metastasis. The researchers suggested the management or disruption of the secretion of this protein could hold a key to preventing cancer from spreading from the pancreas to the liver.
“Understanding the precise mechanisms by which pancreatic cancer metastasizes is a vital part of enhancing our ability to treat this disease,” says Dr. Brad Thompson, president and CEO of Oncolytics Biotech Inc. Oncolytics’ lead compound in development, REOLYSIN®, is in late-stage clinical testing in a range of cancers, including pancreatic cancer.
Where a cancer starts often plays a role in where it will spread, according to the American Cancer Society. Most cancer cells that break free from the original tumor are carried in the blood or lymph until they get trapped in the next “downstream” organ or set of lymph nodes. Once the cells are there, they can start new tumors. This explains why, for example, breast cancer often spreads to underarm lymph nodes, but rarely to lymph nodes in the groin. Likewise, there are many cancers that commonly spread to the lungs. This is because the heart pumps blood from the rest of the body through the lungs’ blood vessels before sending it elsewhere. The liver is a common site of spread for cancer cells that start in the colon because blood from the intestines flows into the liver.
Cancer cells often break away from the main (primary) tumor and travel through the blood and/or lymph system, but they don’t always settle in and start new tumors, the American Cancer Society notes. Most of the time, the cells that broke away die. When cancer does spread to other organs and start to form new tumors, it’s because of certain genetic changes in the cells that scientists are now starting to understand. Someday, doctors may be able to tell if a person’s cancer is the type that will spread to other organs by looking for these genetic changes. Research is also focusing on treatments that block or target these genetic changes so the cancer cells can’t spread and grow.
REOLYSIN® has shown that it may preferentially replicate in cancer cells that have an “activated Ras pathway,” while sparing normal cells. This makes it intrinsically tumor selective without the need for any genetic manipulation of the agent.
With better insight into how pancreatic cancer spreads, the stage is set for a future in which treatments can be better targeted to help patients as much as possible.