Environmental Factor, January 2006, National Institute of Environmental Health Sciences
Gene May Suppress Lung Inflammation
A gene that plays an important role in immune function may also play a critical role in suppressing chronic lung inflammation, NIEHS researchers discovered. That conclusion comes from a study published in the Dec. 7 issue of the Journal of the National Cancer Society.
According to the study, mice prone to lung cancer and that also had an altered or removed toll-like receptor 4, known as TLR4, had about 60 percent more tumors than mice with intact receptors. The study highlights the protective role of this gene, a part of the innate immune system that acts as the body's first line of defense.
Researchers administered a preservative known to cause lung inflammation to determine TLR4's role in inflammation. They then measured tumors in mice with both functional and altered TLR4 genes.
Steve Kleeberger, lab chief in the Laboratory of Respiratory Biology, said TLR4 accounts for a significant portion of the tumors per mouse. He described the role of TLR4 as a braking mechanism in tumor development. When removed, tumor development increases, he said.