PHILADELPHIA (January 03, 2017) – A new study found a link between African ancestry and poor survival rates in patients with head and neck squamous cell carcinoma (HNSCC). The study, by a team of researchers from Fox Chase Cancer Center, Temple University Hospital, and the African-Caribbean Cancer Consortium, appeared early online in the journal Cancer.
Camille Ragin, PhD, MPH, associate professor at Fox Chase, and her team of researchers analyzed data from The Cancer Genome Atlas to search for a genetic explanation for the vast difference in HNSCC survival rates between white and non-white patients. The analysis was led by post-doctoral associate Meganathan Ramakodi, PhD, a member of the Ragin lab. Their work included a study of the genes responsible for DNA repair, and they found that the genotypes containing the African allele showed poorer rates of overall survival and disease-free survival compared with those containing a white allele.
“Disparities in cancer risk and survival outcomes among African Americans are generally attributed to factors such as socioeconomic status and geography,” Ragin said. “Our findings suggest that in addition to these factors, there is an association between ancestry and survival rate disparities for the head and neck cancers we studied.”
The researchers discovered that people with the African allele at a certain genetic position have increased expression of a DNA repair gene that plays an important role in radio resistance, meaning their DNA repair mechanism is more active than that in non-African people.
“Platinum-based chemotherapy and radiation are the first-line treatment options for HNSCC, and both work by damaging the DNA in cancer cells,” Ragin said. “Unfortunately we found that some people may have a biological resistance to both of these therapies, and it may be one reason for the lower survival rates among non-whites.” Further validation of these findings is still needed.
Ragin envisions clinicians relying on this kind of analysis to develop biomarkers that can determine the likelihood that a patient will meaningfully respond to a given therapy.
“This could become an important component of precision medicine that guides treatment options for HNSCC before patients are subjected to treatment,” Ragin said.