NAC for lungs, cancer?

Two recent reports in the journal, Science, looked at two very different conditions. In both cases, they found that the effects that they were seeing were offset when they added one of my favorite antioxidant amino acids, N-acetylcysteine (NAC).

In one case, a study reported on the effects of asbestos and other particulates on the lungs. The article noted that chemotherapy doesn’t really help the lesions that arise from such particulate damage (Dostert et al., Science, 2 May 2008(320)674-677). What they realized was that part of the problem with particulates was that they caused certain inflammatory cytokines, such as interleukin-1beta (IL-1B) to be expressed. At one point in the experiments, they used NAC in cell cultures to evaluate whether reactive oxygen species played a role along with the IL-1B, and indeed, the NAC minimized this response. Would it help as a therapeutic? For people living with HIV and/or hepatitis C, IL-1B has been observed to be elevated (see, e.g., Antivir Chem Chemother. 2001 May;12(3):133-150 and J Viral Hepat. 2008 Mar 6. [Epub ahead of print].)

The second study looked at how a cancer tumor can move to other sites and tissues in the body (metastasis) (Ishikawa, et al., Science, 2 May 2008(320)661-664). Mitochondria, the little powerhouses of cells that produce the energy molecule, ATP, have long thought to be involved in cancer. While damaged mitochondria (or mutations in the DNA mitochondria carry), do not seem to necessarily be the start of cancer, they have been invoked in this study as a source of its metastasis. After determining that their model could indeed cause cancer to spread in mice, they tried NAC to see if they could thwart it. In fact, the reduction of reactive oxygen species (ROS) that NAC achieved did indeed result in reducing the metastatic potential in two mouse models. Address oxidative stress through routine use of antioxidants like NAC MIGHT help to prevent cancer from metastasizing.

This becomes more than just an interesting theory for people with HIV. A recent report underscored a higher risk of certain non-AIDS related cancers in HIV+ individuals. Can agents like NAC help to reduce this risk? No studies have been done in humans to support this idea–but given all the other potential and its safety, many of us are already using it. The report noted:

Anal cancer by 2003 had become 59 times more common among HIV-infected people than the general population, according to the study in the Annals of Internal Medicine.

Hodgkin’s disease was 18 times more common in this population, the study also found. In addition, liver cancer was seven times more common, lung cancer 3.6 times more common, the skin cancer melanoma and throat cancer both three times more common, and colorectal cancer 2.4 times more common.

(See http://www.aegis.org/news/re/2008/RE080516.html )

Advertisements

Leave a Reply

Please log in using one of these methods to post your comment:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s