Cigarette Smoking Appears to Increase Potential for Metastasis of Pancreatic Cancer
Smoking has once again been implicated in the development of advanced cancer. Exposure to nicotine by way of cigarette smoking
may increase the likelihood that pancreatic ductal adenocarcinoma will become metastatic, according to researchers from the
Kimmel Cancer Center at Jefferson. Their study was published in the August edition of the journal Surgery.
The culprit behind the increased metastasis potential appears to be an isoform (variant type) of a protein called osteopontin,
according to Hwyda Arafat, M.D. Ph.D., associate professor of Surgery at Jefferson Medical College of Thomas Jefferson University
and a member of the Jefferson Pancreatic, Biliary & Related Cancers Center.
Nicotine promotes the expression of osteopontin, and high levels of osteopontin have been reported in pancreatic ductal carcinoma
(PDA). Dr. Arafat and her research team 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. Premalignant lesions expressed no OPNc.
“This is the first time a relationship between nicotine and OPNc expression has been identified,” Dr. Arafat said. ”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.”
Pancreatic cancer is the fourth-leading cause of cancer death in the country, taking 34,000 lives a year. Only four percent
of individuals with pancreatic cancer live for five years after diagnosis.
Media Only Contact:Emily ShaferThomas Jefferson University Hospital
Phone: 215-955-6300
Published: 7-27-2009