New research reveals genetic mutations in smoking-related cancers

The new findings arose from a trial of 431 cancer patients between March 2015 to May the following year; the majority of the participants were suffering from lung, colorectal and bladder subtypes, and 13.5% of them were African American. The subjects had their tumours sequenced to zero in on any mutations or genetic changes as a result of smoking or African-American ancestry, and this was referenced against the Cancer Genome Atlas, a dataset which includes 2,821 cases of the disease where smoking is a factor.

While smoking rates were very similar between African-American and Caucasian groups, lead author Wei Zhang, Hanes and Willis Family Professor in Cancer at the Wake Forest School of Medicine, explained: "We know TP53 mutation happens in 55% of all cancer patients. In our study, we found that the African-American population had close to a 70% mutation rate. This data suggests that increases in TP53 mutation in African-Americans may be responsible for the observed resistance to chemotherapy and a poorer prognosis overall."

Beyond this, other genes also showed a greater predisposition for mutation in African-American patients, with genes responsible for DNA repair and chromatin remodelling observed to mutate at higher frequencies in these subjects.

"These results provide strong evidence that genomic instability is a fundamental hallmark of cancer and the events underlying the regulation of genome stability are centered on interactions with environmental factors and lifestyle, such as smoking," Zhang continued.

Zhang believes this knowledge can be used to identify which genes to target through drug therapy in smoking-related cancers, leading to greater patient outcomes through a more effective, personalised approach to treatment.