Reviewing the differences in primary cancer cells (cells found in the primary tumor) and metastatic cancer cells (cells that have migrated to other regions of the body) is helping researchers better understand how cancer grows and spreads throughout the body.
In a recent study conducted at Washington University, scientists analyzed genetic differences between primary and metastatic breast cancer cells culled from the same patient. The research team also looked for differences between the cancer cells and healthy patient cells. In total, the team found 48 different mutations when comparing the cancer cells to healthy cells. In contrast, very few genetic differences were found between primary cancer cells and metastatic cancer cells.
However, the team did note a large difference in the frequency of mutations when looking at both types of cancer cells. Specifically, it was discovered that metastatic breast cancer cells that had migrated to the brain were far more likely to contain 20 of the 48 identified mutations.
Of these 20 genetic mutations, the research team believes one or several may be directly related to a cancer’s ability to spread within the body. For example, an identified gene labeled as CTNNA1 has previously been shown as a key component for helping cells stick to surrounding cells. Metastatic cells in the study frequently lacked this gene, which might suggest these cells are more likely to break free from the primary tumor location and head off to another region of the body.
As Richard Wilson, the senior author for the study and director of the Genome Sequencing Center at Washington University, suggests, “It’s as if a small subset of cells broke off from the primary tumor, circulated through blood, found a new home in the brain, and began to grow wildly and out of control.”
The findings are spurring hope among the researchers that cancer medications can eventually be made that specifically target the mutated genes that help a cancer spread. However, before this can be done, the research must be validated from studies that incorporate a high volume of patients. The Washington University team already has these high-volume tests in the works – several hundred unique cancer genome sequences are set to be completed in the coming year.