Featured Research

from universities, journals, and other organizations

Study details cancer-promoting mechanisms of overlooked components in secondhand smoke

Date:
June 25, 2013
Source:
University of Colorado Denver
Summary:
A new study shows that overlooked components of secondhand smoke may help the more well known molecules like BaP cause and promote cancer.

Tobacco smoke, diesel exhaust and oil combustion carry polycyclic aromatic hydrocarbons -- PAHs that are known to cause cancer. But of these PAHs, the obviously dangerous high-molecular-weight PAHs like benzo[a]pyrene (BaP) have received the vast majority of research attention. Their low-molecular-weight cousins have been largely overlooked, in part because studies have shown that these compounds alone aren't very successful at mutating genes in cancer-causing ways.

A University of Colorado Cancer Center study published in the journal PLoS One explores two of these low-molecular-weight (LMW) PAHs -- 1-methylanthracene (1-MeA) and 2-methylanthracene (2-MeA) -- and shows that while they don't necessarily cause cancer, 1-MeA promotes conditions that will likely allow cancer to grow.

"There's a big distinction between initiating cancer and promoting it," says Alison Bauer, PhD, CU Cancer Center investigator and assistant professor at the Colorado School of Public Health. Her study showed that in a mouse cell model using a progenitor cell of lung cancer, the LMW 1-MeA promoted inflammation and increased mitogenic pathways, both of which are linked to tumor promotion. 2-MeA, while nearly structurally identical, did not.

"These LMW PAHs have been considered less of a concern," Bauer says, "but we're finding evidence that's not the case. They're not likely initiating the cancer, but it looks as if they could promote it."

Among other effects, Bauer and colleagues found that 1-MeA disrupts communication between cells, affecting the "gap junctions" across which adjoining cells pass information. 1-MeA also upregulates the gene COX2, which has been shown in other studies to create an over-aggressive inflammatory response -- and this inflammation in turn can promote tumor growth.

"There are many different PAHs in secondhand smoke," Bauer says. "Some are obviously dangerous like BaP, which directly mutates genes. Others, like 1-MeA, we known very little about. Think about all these PAHs like chess pieces -- first you have to know how each piece moves and then you can start looking at how they all work together."

Bauer points to these PAH mixtures as the next step in research. Eventually, knowing the effects of these mixtures could help evaluate the risks of different combustion products. The work could also lead to new therapy targets if, perhaps, some of the changes promoted by these LMW PAHs prove preventable or reversible by medicines.

"With smoking rates decreasing, we think this problem is going away, but high levels of secondhand smoke still exist in the U.S., for example in some apartment buildings," Bauer says. "And around the world, in China, Russia, Poland and many other countries, secondhand smoke is still a major issue. Knowing the effects of these LMW PAHs like 1-MeA could help us prevent or treat cancers associated with them."


Story Source:

The above story is based on materials provided by University of Colorado Denver. The original article was written by Garth Sundem. Note: Materials may be edited for content and length.


Journal Reference:

  1. Ross S. Osgood, Brad L. Upham, Thomas Hill, Katherine L. Helms, Kalpana Velmurugan, Pavel Babica, Alison K. Bauer. Polycyclic Aromatic Hydrocarbon-Induced Signaling Events Relevant to Inflammation and Tumorigenesis in Lung Cells Are Dependent on Molecular Structure. PLoS ONE, 2013; 8 (6): e65150 DOI: 10.1371/journal.pone.0065150

Cite This Page:

University of Colorado Denver. "Study details cancer-promoting mechanisms of overlooked components in secondhand smoke." ScienceDaily. ScienceDaily, 25 June 2013. <www.sciencedaily.com/releases/2013/06/130625150940.htm>.
University of Colorado Denver. (2013, June 25). Study details cancer-promoting mechanisms of overlooked components in secondhand smoke. ScienceDaily. Retrieved October 20, 2014 from www.sciencedaily.com/releases/2013/06/130625150940.htm
University of Colorado Denver. "Study details cancer-promoting mechanisms of overlooked components in secondhand smoke." ScienceDaily. www.sciencedaily.com/releases/2013/06/130625150940.htm (accessed October 20, 2014).

Share This



More Health & Medicine News

Monday, October 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

How Nigeria Beat Its Ebola Outbreak

How Nigeria Beat Its Ebola Outbreak

Newsy (Oct. 20, 2014) The World Health Organization has declared Nigeria free of Ebola. Health experts credit a bit of luck and the government's initial response. Video provided by Newsy
Powered by NewsLook.com
Another Study Suggests Viagra Is Good For The Heart

Another Study Suggests Viagra Is Good For The Heart

Newsy (Oct. 20, 2014) An ingredient in erectile-dysfunction medications such as Viagra could improve heart function. Perhaps not surprising, given Viagra's history. Video provided by Newsy
Powered by NewsLook.com
Ebola Worries End for Dozens on U.S. Watch Lists

Ebola Worries End for Dozens on U.S. Watch Lists

Reuters - US Online Video (Oct. 20, 2014) Forty-three people who had contact with Thomas Eric Duncan, the first person diagnosed with Ebola in the U.S., were cleared overnight of twice-daily monitoring after 21 days of showing no symptoms. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Fauci: Ebola Protocols to Focus on Training

Fauci: Ebola Protocols to Focus on Training

AP (Oct. 20, 2014) Dr. Anthony Fauci, head of the National Institute of Allergy and Infectious Diseases, says he expects revised CDC protocols on Ebola to focus on training, observation and ensuring health care workers are more protected. (Oct. 20) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins