Normal Genetics May Influence Cancer Growth
A person’s genetic background – the array of inherited genetic variations – may contribute to DNA changes that occur in tumor cells as cancer develops, an OSUCCC – James study suggests.
Comparing multiple independent tumors from people with squamous cell carcinoma (SCC) for DNA losses and gains in tumor cells, scientists found that the pattern of changes is quite similar in tumors from the same person but quite different in tumors from different individuals. The findings could help identify individuals at greater risk for developing cancer.
“Our data strongly support the idea that an individual’s normal genetic constitution can strongly influence genetic changes that occur when he or she develops cancer,” says study leader Amanda Toland, PhD, of the Molecular Biology and Cancer Genetics Program at the OSUCCC – James. “They may also provide another strategy for identifying genetic variations within healthy individuals that increase their odds of developing cancer.”
Toland and collaborators analyzed 222 SCC tumors from 135 organ transplant recipients, who as a group are 65 to 250 times more likely to develop SCC than people in the general population. The researchers examined three or more separate tumors from 25 of these individuals.
When they compared the genetic profiles of tumors from the same individual with those from other individuals for DNA copy number changes, they found that the changes in SCCs from the same patient were statistically similar but were significantly different when compared with other patients. They also found that, in some cases, a particular kind of genetic change is preferentially selected in tumors from the same individual.
“Overall,” Toland says, “our findings provide strong evidence that an individual’s genetic background plays a key role in driving the changes that occur in tumors during cancer development.”
Published in the journal Public Library of Science Genetics.