Exposure to tobacco smoke is linked to both an elevated risk of nasopharyngeal carcinoma (NPC) as well as Epstein-Barr Virus (EBV) seropositivity in males and is involved in EBV activation, according to a study published in the Journal of the National Cancer Institute.

NPC is rare throughout most of the world, but common in South China and Southeast Asia. EBV is associated with the occurrence and development of NPC.

Some long-term studies have reported elevated levels of antibodies against EBV antigens in serum that precede the development of NPC and may have a causal role in it, but other factors, namely lifestyle factors such as smoking and eating habits, have also been linked to a higher risk of NPC. Furthermore, the molecular mechanism behind EBV seroreactivity is largely unknown.

In order to better determine the link between EBV and NPC, Wei-Hua Jia, M.D., Ph.D. and Mu-Sheng Zeng, Ph.D., of the Sun Yat-sen University Cancer Center in China and colleagues looked at data from male patients living in the Guandong Province, an area in China known for high NPC risk, to determine potential NPC risk factors and EBV inducers.

They then compared the data to two independent healthy male populations from high and low risk areas. The effects of cigarette smoke extract on EBV activation in two EBV-positive cell lines were determined by in vitro experiments.

The researchers found that smoking increases the risk of NPC and is also linked to EBV activation in healthy males. Indeed, the researchers write, “The novelty of the current study is the establishment of a robust link between cigarette smoking and EBV activation. On the basis of our findings, cigarette smoking cessation programs should be advocated for the primary prevention of NPC in China, especially in NPC endemic areas.” Furthermore, the authors add that, “searching for more environmental inducers specific to NPC high-risk areas has great value in NPC prevention.”

Source: JNCI