Since its inception in 1990 and relative completion in 2003, the collaborative sequencing of human DNA known as the Human Genome Project (HGP) has helped the medical field understand various diseases. Moreover, since 2006 The Cancer Genome Atlas (TCGA) has characterized mutations in thousands of cancerscovering 33 cancer types paving the way for more accurate diagnosis and treatments. Oncology, the branch of medicine concerned with preventing, diagnosing, and treating cancer, is at the forefront of the innovative practices currently being explored using DNA testing. According to the World Health Organization (WHO), more than 40 million people worldwide are living with a type of cancer. Statistics suggest that one in five men and one in six women will develop cancer during their lifetime, stressing the urgency to create early detection policies to ensure a timely diagnosis with complementary treatment.
Dr. Kevin Dalby, a recipient of funding by the Cancer Prevention and Research Institute of Texas (CPRIT) and the National Institutes of Health, studies the mechanisms of cancer cell signaling to develop targeted therapeutics. Through his research and efforts as a professor at The University of Texas in Austin, he hopes to improve diagnoses and utilize technological advances to develop targeted pharmaceuticals for different cancers.
In this article, Kevin Dalby reviews the DNA testing methods driving profound change in the way oncologists approach disease management.
Genetic testing for cancer susceptibility
At present, imaging scans and surgical tissue biopsies are the favored technology to diagnose cancer, though both are imperfect and limited in scope as far as early detection is concerned. Standard imaging struggles to detect the smallest cancers, while biopsies are painful and invasive to the patient.
Early detection and treatment significantly improve a cancer patient’s outlook and ultimate survival rate, which is why next-generation sequencing (NGS) technology is promising. As much as 5% to 10% of cancers have a genetic element, meaning that NGS sequencing allows doctors to test genes that may increase susceptibility to disease long before the onset of illness. While not everyone is an ideal candidate for predictive genetic testing, individuals who have a family history of hereditary cancer should consider oncology genetics. A single specimen can evaluate results for an entire family, thus decreasing the diagnosis time frame and reducing financial burden. NGS is already being utilized for several common cancer types, including breast and ovarian, gastrointestinal as well as pancreatic.
Medical centers throughout the world are embracing genetic sequencing and encouraging patients to participate in studies. Still, the most significant advancement in cancer comprehension and treatment may come from our blood.
Cancer blood tests
Traditional screening programs are expensive, provide false positives, and altogether miss people who don’t undergo routine screenings appropriate for their age. However, advancements in DNA testing open the door for reliable pre-symptomatic detection. San Diego-based Illumina is now developing a cancer blood test (aka liquid biopsy) to identify fragments in the blood from cancerous cells. The presence of cancer-causing mutations in DNA may indicate the early formation of a tumor well before it appears on a body scan.
As more companies find success in clinical trials, liquid biopsies will become mainstream and standard practice in annual physical exams. Furthermore, for patients already battling cancer, oncologists can use the latest testing as a means to determine if an operation or procedure successfully removed 100% of the malignant cells.
The medical community remains in a heated battle against a mutating enemy, but DNA testing provides hope for the future. As oncologists continue the fight to understand cancers better at a cellular level, they can provide more personalized treatment, and, one day, defeat the diseases indefinitely.
About Dr. Kevin Dalby:
Dr. Kevin Dalby is a professor of chemical biology and medicinal chemistry, currently working on cancer drug discovery. At the College of Pharmacy at The University of Texas, he is examining the mechanisms of cancer to develop new treatments, while teaching and motivating students to conduct research. Dalby is optimistic about the future of cancer treatments.