The American Physiological Society Press Release

press release logo

APS Contact: Stacy Brooks


Phone: 301.634.7209

Twitter: @APSPhysiology

Chinese Herbal Extract May Help Kill Off Pancreatic Cancer Cells

Bethesda, Md. (July 1, 2014) — A diagnosis of pancreatic cancer—the fourth most common cause of cancer death in the U.S.—can be devastating. Due in part to aggressive cell replication and tumor growth, pancreatic cancer progresses quickly and has a low five-year survival rate (less than 5 percent).

GRP78, a protein that protects cells from dying, is more abundant in cancer cells and tissue than in normal organs and is thought to play a role in helping pancreatic cancer cells survive and thrive. Researchers at the University of Minnesota have found triptolide, an extract of the Chinese herb thunder god vine (Tirpterygium wilforii), suppresses GRP78, eventually leading to pancreatic cancer cell death.

For mammals to use the proteins in our bodies, a process called protein folding must occur in the endoplasmic reticulum (ER) of cells. If proteins are not folded fast enough, unfolded proteins begin to build up and the cell becomes stressed. Prolonged ER stress activates a cellular process called the “unfolded protein response (UPR)”. Initially, the UPR helps kick-start the cell’s protein-folding ability, allowing it to function properly again. But if the problem doesn’t resolve, the UPR triggers cell death.  

GRP78 helps cells survive long enough for the UPR to kick in and correct protein-folding problems. However, GRP78 is available in higher quantities in pancreatic cancer cells, which assists the cancer cells in evading cell death, allowing them to live and multiply.

Triptolide has previously been shown to have a negative effect on pancreatic cancer cell viability and to block growth and spread of these cells. In this study led by Ashok Saluja, Ph.D., researchers observed the effects of triptolide on human pancreatic cancer cells and tissue. They found that the UPR worked properly in triptolide-treated cells to allow cell death in malfunctioning cells. 

“Our study shows that although increased expression of GRP78 confers a survival advantage to the tumor cells, prolonged exposure to triptolide induces chronic ER stress, which eventually leads to cell death,” the authors stated. “In this context, inhibition of GRP78 by activation of the ER stress pathway by triptolide offers a novel mechanism for inhibiting the growth and survival of pancreatic cancer cells.”

The article “Triptolide activates unfolded protein response leading to chronic ER stress in pancreatic cancer cells” is published in the American Journal of Physiology—Gastrointestinal and Liver Physiology. It is highlighted as one of this month’s “best of the best” as part of the American Physiological Society’s APSselect program. View the full study here: Read all of this month’s selected research articles at

NOTE TO JOURNALISTS: To schedule an interview with a member of the research team, please contact Stacy Brooks at or 301-634-7209.

Physiology is the study of how molecules, cells, tissues and organs function in health and disease. Established in 1887, the American Physiological Society (APS) was the first U.S. society in the biomedical sciences field. The Society represents more than 11,000 members and publishes 14 peer-reviewed journals with a worldwide readership.



The American Physiological Society Launches APSselect

Released January 31, 2014 - January 2014 marks the beginning of an exciting new initiative for the Society. Our new virtual journal, entitled APSselect, will highlight the “best of the best” of the some 250 papers published each month by the Society’s 10 research journals.

Stem Cell Therapy May Help Recondition Lungs Previously Rejected for Transplant

Released May 30, 2014 - International team of researchers use stem cells therapy to “recondition” abnormally functioning lungs previously rejected for transplant. Study could have implications for increasing the supply of suitable donor lungs. The article is highlighted as part of the APSselect program.

APS Awards $386,000 to Its 2014 Undergraduate Research Fellows

Released July 22, 2014 - The APS is pleased to announce the recipients of its five summer fellowship programs for 2014. Fellows spend an average of 10 weeks in the laboratory of an established scientist and APS member.

Keep Calm Moms: Maternal Stress during Pregnancy Linked to Asthma Risk in Offspring

Released August 1, 2014 - Harvard researchers find that a single bout of stress during pregnancy can affect allergy and asthma susceptibility in neonates. The article is published in AJP – Lung Cellular and Molecular Physiology and was chosen as one of this month’s APSselect articles.