Cancer is most dangerous when it spreads, or metastasizes, throughout the body. Now, scientists have found that the mutations that are responsible for cancer growth are the same in all tumors in a single patient.
The finding could be a boon to doctors aiming to treat cancer by targeting mutations responsible for its growth.
A paper describing the work was published in Science. Radiologist Johannes Reiter, PhD, is the first author.
The research looked at mutations known as driver mutations, which spur cancer growth. Reiter and his colleagues examined DNA samples from 76 untreated metastases from 20 patients with eight different cancer types.
Our press release explains:
Like choosing the right suspects in a lineup, the scientists picked out the mutations that occurred in known driver genes and investigated whether or not they were found in all the sampled metastases of an individual patient. In some cancers, the researchers only identified two driver gene mutations; in others, there were as many as 18.
By analyzing their data against massive databases that hold mutational data of more than 25,000 previously sequenced cancers, they found that the driver gene mutations that were shared among all metastases in an individual were also frequently mutated in previously sequenced cancers, indicating that these mutations are the true drivers of the disease and play a critical role during cancer development.
And as to driver genes that weren't found in all of a patient's tumors? Well, their contributions were less significant — they could be considered mere passengers.
Because this study sample was so small, Reiter said it is too early to generalize the results.
But if they hold up in larger studies, it could allow clinicians to correctly identify a driver gene found in all of a patient's tumors to target therapeutically.
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