Researchers say exposure to nicotine through cigarettes can significantly elevate the risk of pancreatic cancer to become metastatic.
Researchers from the Kimmel Cancer Center at Jefferson claim that isoform (variant type) of a protein called osteopontin might be a key to increased metastasis potential.
Dr. Hwyda Arafat, an associate professor of Surgery at Jefferson Medical College of Thomas Jefferson University and a member of the Jefferson Pancreatic, Biliary and Related Cancers Center said that nicotine promotes the expression osteopontin, and high levels of osteopontin have been reported in pancreatic ductal carcinoma (PDA).
During the study, the researchers analyzed PDA samples and confirmed that the isoform, called OPNc, was also expressed on invasive PDA lesions.
Previous studies have shown that OPNc is expressed in several invasive cancers, and supports metastatic behavior.
The researchers correlated OPNc expression with the patients' smoking history.
OPNc expression was found on 87 percent of the invasive PDA lesions analyzed, of which 73 percent were from smokers.
The OPNc expression also correlated with higher expression levels of osteopontin.
"This is the first time a relationship between nicotine and OPNc expression has been identified," said Arafat.
"These data are very exciting because now we can evaluate OPNc as a prognostic and diagnostic marker of invasive PDA lesions.
"Because of the lower expression levels of OPNc in non-smokers, OPNc may be regulated by nicotine, which is another novel finding of this study.
"The exact role of OPNc in PDA remains to be defined, but it could provide a unique potential target to control pancreatic cancer aggressiveness, especially in people who smoke cigarettes," she added.
The study is published in journal Surgery.