|
Although scientists still do not know exactly what causes most
cases of pancreatic cancer, they have found several risk factors that
can make a person more likely to get this disease. Recent research has
shown that some of these risk factors affect the DNA of cells in the
pancreas, which can result in abnormal cell growth and may cause tumors
to form.
Researchers have made great progress in understanding how
certain changes in DNA can cause normal cells to become cancerous. DNA
is the chemical in each cell that carries our genes -- the instructions
for how our cells function. We look like our parents because they are
the source of our DNA. But DNA affects more than our outward
appearance. Some genes contain instructions for controlling when our
cells grow and divide. Certain genes that promote cell division are
called oncogenes. Others that slow down cell division or cause cells to
die at the right time are called tumor suppressor genes. Cancers can be
caused by DNA mutations (defects) that turn on oncogenes or turn off
tumor suppressor genes.
Several cancer family syndromes have been found in which
inherited DNA mutations cause a very high risk of developing certain
cancers. In some of these, there is an increased risk of getting
pancreatic cancer. Researchers have characterized many of these DNA
changes in the past few years (see the section, "What
are the risk factors for pancreatic cancer?").
Most often, DNA mutations of oncogenes or tumor suppressor
genes related to cancers of the pancreas occur after you are born,
rather than having been inherited. These acquired mutations may result
from cancer-causing chemicals in our environment, diet, or tobacco
smoke. Sometimes they occur for no apparent reason.
Often, the DNA changes seen in sporadic (non-inherited) cases
of pancreatic cancer are the same as those seen in inherited cases. For
example, most sporadic cases of exocrine pancreatic cancer have changes
in the p16 gene. Because of this, scientists are studying inherited
cases closely to learn more about what causes pancreatic cancer. Some
specific DNA abnormalities recently discovered in pancreatic cancer are
discussed in the section, "What's
new in pancreatic cancer research and treatment?"
Last Medical Review: 10/13/2009
Last Revised: 10/13/2009
|
