Lung cancer affects both smokers and nonsmokers, killing more than half of the people who get it within five years. It has been notoriously hard to treat, frequently resulting in widespread resistance and nasty side effects from high doses of drugs.

Delivering anti-cancer drugs and compounds to suppress resistance more directly to the lungs via inhalation—rather than intravenously—might be a better way to knock out the cancerous cells while sparing other major organs, according to new research. The new study, published online May 24 in the Proceedings of the National Academy of Sciences, shows this method, also used to administer drugs to treat asthma or chronic obstructive pulmonary disease, would improve outcomes by sending more of the treatment directly to the cancer cells while limiting damage to other organs.

To test their idea, researchers gave mice human lung cancer tumors and then started them on various treatment regimens. A control group received no treatment; two groups received different types of the popular anti-cancer agent doxorubicin intravenously; and three groups received doxorubicin either alone or in combination with other inhibitory compounds.

The researchers, led by Olga Garbuzenko, of the Department of Pharmaceutics at Rutgers University, found that inhaled treatments outperformed those that were given intravenously, shrinking tumors more effectively. But the best results were achieved in the mice that were given doxorubicin in combination with a complex cocktail of compounds, which included antisense oligonucleotides and short-inferring RNA, both of which help stop resistance from developing. "Such a degree of regression of tumor growth could not be achieved by the individual components" alone, the researchers noted.

Despite the additional agents in these cocktail treatment groups, the other major organs came out of the regime in much better shape than those mice on the traditional I.V. groups. "Local inhalation delivery of [doxorubicin]… limited adverse side effects of the treatment on healthy organs," the researchers concluded.

Image of lung cancer tumor in human courtesy of Wikimedia Commons