Caption: Human colon cancer cells. Credit: National Cancer Institute, NIH
Thanks to improvements in screening technologies and public health outreach, more cancers are being detected early. While that’s life-saving news for many people, it does raise some important questions about the management of small, early-stage tumors. Do some tumors take a long time to smolder in their original location before they spread, or metastasize, while others track to new, distant, and dangerous sites early in their course? Or, as the authors of a new NIH-funded study put it, are certain tumors just “born to be bad”?
To get some answers, these researchers recently used genomic data from 19 human colorectal tumors (malignant and benign) to model tumor development over time . Their computer simulations showed that malignant tumors displayed distinctive spatial patterns of genetic mutations associated with early cell mobility. Cell mobility is a prerequisite for malignancy, and it indicates an elevated risk of tumors invading the surrounding tissue and spreading to other parts of the body. What’s more, the team’s experimental work uncovered evidence of early abnormal cell movement in more than half of the invasive tumors.
Much more remains to be done to validate these findings and extend them to other types of cancer. But the study suggests that spatial mutation patterns may someday prove useful in helping decide whether to pursue aggressive treatment for early-stage cancer or opt for careful monitoring instead.
NIH-funded researchers analyzed the DNA of these cancers.
Cancer is a disease of the genome. It arises when genes involved in promoting or suppressing cell growth sustain mutations that disturb the normal stop and go signals. There are more than 100 different types of cancer, most of which derive their names and current treatment based on their tissue of origin—breast, colon, or brain, for example. But because of advances in DNA sequencing and analysis, that soon may be about to change.
Using data generated through The Cancer Genome Atlas, NIH-funded researchers recently compared the genomic fingerprints of tumor samples from nearly 3,300 patients with 12 types of cancer: acute myeloid leukemia, bladder, brain (glioblastoma multiforme), breast, colon, endometrial, head and neck, kidney, lung (adenocarcinoma and squamous cell carcinoma), ovarian, and rectal. Confirming but greatly extending what smaller studies have shown, the researchers discovered that even when cancers originate from vastly different tissues, they can show similar features at the DNA level