Nav: Home

Noninvasive detection for early stage cancers from circulating DNA

August 16, 2017

A new DNA sequencing-based method could help noninvasively detect early stage cancers by analyzing fragments of genetic material circulating in the blood that originate from tumors. The findings may pave the way to more useful screening and management tools for patients with cancer. More than 14 million people globally are diagnosed with cancer every year, and most cases aren't detected until the disease has progressed to late stages with few treatment options. As such, early detection and clinical interventions for colorectal, ovarian, lung, and breast cancers might save as many as one million lives annually. Jillian Phallen and colleagues developed an ultrasensitive approach to identify molecular signatures of cancer from small pieces of genetic material released by cancer cells into the bloodstream called circulating tumor DNA (ctDNA). Plasma from 194 patients with colorectal, ovarian, lung, and breast cancers frequently contained ctDNA with mutations in one or more of 58 so-called cancer driver genes, unlike samples from 44 healthy individuals. Because ctDNA comprises a tiny fraction of the total DNA present in the blood (called cell-free DNA, or cfDNA), the scientists developed a new sample-preparation and computational analysis pipeline, which they dubbed TEC-Seq. By sequencing every molecule tens of thousands of times, the researchers picked out ctDNA and distinguished between cancer-associated alterations and normal variation in cfDNA with a false positive rate of fewer than one per three million DNA base pairs. On average, cancer patients had over four times more cfDNA in their blood overall as compared to healthy subjects, and increased levels correlated with more aggressive disease. The authors say analyzing a broader panel of driver genes may further boost the sensitivity and specificity of TEC-Seq.
-end-


American Association for the Advancement of Science

Related Cancer Articles:

Stress in cervical cancer patients associated with higher risk of cancer-specific mortality
Psychological stress was associated with a higher risk of cancer-specific mortality in women diagnosed with cervical cancer.
Cancer-sniffing dogs 97% accurate in identifying lung cancer, according to study in JAOA
The next step will be to further fractionate the samples based on chemical and physical properties, presenting them back to the dogs until the specific biomarkers for each cancer are identified.
Moffitt Cancer Center researchers identify one way T cell function may fail in cancer
Moffitt Cancer Center researchers have discovered a mechanism by which one type of immune cell, CD8+ T cells, can become dysfunctional, impeding its ability to seek and kill cancer cells.
More cancer survivors, fewer cancer specialists point to challenge in meeting care needs
An aging population, a growing number of cancer survivors, and a projected shortage of cancer care providers will result in a challenge in delivering the care for cancer survivors in the United States if systemic changes are not made.
New cancer vaccine platform a potential tool for efficacious targeted cancer therapy
Researchers at the University of Helsinki have discovered a solution in the form of a cancer vaccine platform for improving the efficacy of oncolytic viruses used in cancer treatment.
More Cancer News and Cancer Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Erasing The Stigma
Many of us either cope with mental illness or know someone who does. But we still have a hard time talking about it. This hour, TED speakers explore ways to push past — and even erase — the stigma. Guests include musician and comedian Jordan Raskopoulos, neuroscientist and psychiatrist Thomas Insel, psychiatrist Dixon Chibanda, anxiety and depression researcher Olivia Remes, and entrepreneur Sangu Delle.
Now Playing: Science for the People

#537 Science Journalism, Hold the Hype
Everyone's seen a piece of science getting over-exaggerated in the media. Most people would be quick to blame journalists and big media for getting in wrong. In many cases, you'd be right. But there's other sources of hype in science journalism. and one of them can be found in the humble, and little-known press release. We're talking with Chris Chambers about doing science about science journalism, and where the hype creeps in. Related links: The association between exaggeration in health related science news and academic press releases: retrospective observational study Claims of causality in health news: a randomised trial This...