Smoking Linked to Breast Cancer Risk

Smoking Linked to Breast Cancer Risk

Joined: 18 Dec 2008, 23:57

11 May 2001, 05:33 #1

http://dailynews.yahoo.com/h/nm/2001050 ... ast_1.html

Wednesday May 9 6:36 PM ET
Cigarette Smoking Linked to Breast Cancer Risk


By Will Boggs, MD

NEW YORK (Reuters Health) - Smoking is a major risk factor for breast cancer among women with a family history of breast or ovarian cancer, US researchers report.

Their study of 132 families with at least three breast or ovarian cancer patients found that patients' sisters and daughters who smoked were more than twice as likely to develop breast cancer, compared with the nonsmoking sisters and daughters of patients.

Smoking did not appear to increase the risk among patients' nieces and granddaughters, however, according to the report published in the April issue of Cancer Epidemiology, Biomarkers & Prevention.

In families with the strongest genetic risk--those with at least five members with cancer--smoking was an even more significant risk factor. Patients' sisters and daughters who smoked at some point in their lives were nearly six times more likely to develop breast cancer than relatives who never smoked.

``Breast cancer is not typically thought of as a smoking-associated malignancy but for susceptible women it could be quite an important contributor,'' Dr. Thomas A. Sellers of the Mayo Clinic in Rochester, Minnesota, and the study's senior author, told Reuters Health.

The researchers explain that smoking boosts carcinogens, or cancer-causing chemicals, in the blood. These chemicals can cause mutations in the DNA of breast cells which, over time, lead to cancer.

The study authors call for further research into the link between cigarette smoking and breast cancer among women with a genetic risk.

``If you don't smoke, don't start. If you do smoke, it's never too late to quit,'' Sellers said.

SOURCE: Cancer Epidemiology, Biomarkers & Prevention 2001;10:327-332.
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Joined: 18 Dec 2008, 23:57

11 May 2001, 05:39 #2

http://www2.cancer.org/zine/index.cfm?fn=001_05032001_0

Today's Date: May 10, 2001


Tobacco Use, Genetics May Increase Breast Cancer Risk


May 3, 2001 (ACS NewsToday) --- Smoking may put women with a family history of breast and ovarian cancers at greater risk of developing breast cancer themselves, according to a study published in Cancer Epidemiology, Biomarkers & Prevention, (Vol. 10, No. 4: 327-332).

The multigenerational study contradicts a May 1998 paper published in the Journal of the National Cancer Institute that suggested tobacco might be a protective factor, reducing the risk of breast cancer in women with the mutant BRCA1 or BRCA2 gene, an inherited defect associated with higher risk for breast and ovarian cancers. It is not clear why tobacco may have been considered protective, although some investigators believed it may have been due to decreased estrogen levels in women who were smokers.

"The most important finding was that smoking did not lower the risk of breast cancer in high-risk families," says the new paper's senior author, Thomas A. Sellers, PhD, an epidemiologist and associate director of the Mayo cancer center. "This is one more reason to avoid smoking."

In this study, researchers from the Mayo Clinic Cancer Center looked at breast and ovarian cancer cases in female relatives of 426 women whose families had a high incidence of those cancers, and who had been diagnosed with breast cancer between 1944 and 1952.

The researchers analyzed a subgroup of 132 families that had at least three cases of breast or ovarian cancers by the end of the follow-up period of 1991 to 1996. Among the sisters and daughters in these higher-risk families, those who smoked were at a 2.4-fold increased risk of breast cancer over those who had never smoked. (Sisters and daughters share 50% of the genes of the original cancer patient.)

In 35 families with the highest genetic risk - that is, there were at least five cases of breast or ovarian cancers in the family history - sisters and daughters who smoked had more than double the risk of developing breast cancer than the nonsmokers. The increased risk among smoking granddaughters and nieces-who share 25% of the original patient's genes-was 1.7-fold.

Small group of highest-risk patients weakens the conclusion

The data linking cigarette smoking and breast cancer are mixed, with most published studies finding a weak link. Marilyn Leitch, MD, a member of the American Cancer Society breast cancer council and medical director at the University of Texas Southwestern Center for Breast Care, cautions that the number of families in the highest-risk genetic group - 35 - is small, making it difficult to conclude with certainty that smoking definitely increases the risk of developing breast cancer in predisposed women with positive family histories.

"The smokers were more likely to drink alcohol," says Leitch, "which is also shown to be a risk factor for development of breast cancer."

At the Mayo Clinic, Sellers offers two possible reasons for why his study, found an apparent link to the disease. This study is the first to look at multiple generations of families with breast cancer, he says. If smoking is more dangerous for a certain group of susceptible women, previous studies may have missed the thread of that inherited susceptibility, Seller says. Secondly, the age at which women begin smoking has dropped dramatically during 30 years of breast cancer research, he says.

"In 2001, 95% of all smokers begin before age 18," says Sellers. "So if women are exposed during adolescence when breast tissues are growing and dividing rapidly, that may be a more critical period."

He expected to find that if smoking actually increased the risk of breast cancer, as it does in lung cancer, the more women smoked and the longer they smoked, the greater the risk of developing breast cancer. The Mayo group did not see that, however. The team also did not have enough cases to look at the risks of women who never smoked versus former smokers versus current smokers. As a result, the study could not determine whether a woman would decrease her risk of developing breast cancer if she stopped smoking. "It's an important question," Sellers says, "and additional research is needed to sort that out."
Last edited by John (Gold) on 29 Jul 2010, 18:15, edited 1 time in total.
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11 May 2001, 20:45 #3

thanks for posting this zep
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Joined: 18 Dec 2008, 23:57

10 Aug 2002, 00:38 #4

John's Note: The above articles were published in May 2001 and this thread was started at that time. Below is a new study review just released in the British Medical Journal dated August 10, 2002

BMJ 2002;325:298 - 10 August, 2002
http://bmj.com/cgi/content/full/325/7359/298/d


News extra Risk of breast cancer increases
with number of years' smoking
Roger Dobson Abergavenny

Women who smoke for many years may increase their risk of developing breast cancer. New research shows that for women who had smoked for 40 years or longer, the risk of breast cancer was 60% higher than that of women who had never smoked.

Among those who smoked 20 cigarettes or more a day for 40 years, the increased risk rose to 83%.

"Our findings suggest that smoking of very long duration and high intensity may be associated with increased risk of breast cancer," said the researchers, who say that few studies have looked at whether risk of breast cancer is associated with long term smoking.

The researchers, from Albert Einstein College of Medicine, Bronx, New York, examined the association between cigarette smoking and incidence of breast cancer in a cohort of women who had smoked for up to 40 years at recruitment in the early 1980s; the women were subsequently followed for an average of 10.6 years (International Journal of Cancer 2002:100:723-8).

The research, using data from almost 90 000 women in the Canadian national breast screening study, found that smoking intensity, smoking duration, years since smoking started, and pack years of cigarette consumption had positive associations with breast cancer risk. But age at which smoking began and years since quitting among former smokers were not clearly associated with risk.

The researchers said that the positive association between smoking and breast cancer risk was driven largely by women who had smoked for 40 years, especially those who had smoked 20 cigarettes a day or more.

The study found that women who had smoked either at least one pack of cigarettes a day for 40 years or at least two packs a day for 20 years were at noticeably higher risk than women who accrued the same number of pack years over a shorter duration.

It adds, "Our findings, with respect to risk in association with duration of smoking years since smoking commencement and years since quitting, suggest that smoking may act primarily as an initiator rather than as a promoter of breast cancer, as has been hypothesised with respect to colorectal cancer."

The researchers say that tobacco smoke contains many potentially harmful substances, including nitrogen oxides, volatile aldehydes, alkenes, and aromatic hydrocarbons, which may act differently and at different stages in the development of breast cancer.

They add, "Since prospective cohort studies that have examined breast cancer incidence in relation to smoking duration of 30-40 years or more are scarce, confirmatory data are needed."
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07 Sep 2002, 15:07 #5

Australian scientists link smoking to ovarian cancer
Sydney, Sept 4, 2002 (ANI):

It is a well-know fact that smoking increases ones risk of developing lung cancer. Now, Australian researchers claim to have found a link between smoking and ovarian cancer for the first time.

The study involved more than 1600 women, about half of whom had ovarian cancer.

According to scientists at the Queensland Institute of Medical Research, the findings came as a surprise.

"Because smoking doesnt actually come into contact with the ovaries, as it does with the lung, most researchers thought ... theres not going to be an association. Although its not a very strong link - not nearly as strong as the type of risk that youll find for lung cancer - women who smoke definitely are about twice as likely to get ovarian cancer as women who dont smoke," Dr David Purdie was quoted as saying.

The research also showed that women who had several children and those taking contraceptive pills were less likely to get the cancer because the pill triggered a protective effect similar to pregnancy.
Estd. 2001 © Copyright Navakal,Inc. All rights reserved worldwide.[/size]
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04 Oct 2002, 20:12 #6

Smoking Within Five Years of First
Period Linked to Breast Cancer Risks

Another new Canadian breast cancer study was just published in Lancet, a respected UK medical journal and a new thread has been started. It too suggests that further studies are necessary to confirm its finding that in premenopausal women, the risk of breast cancer was substantially elevated in women who had begun smoking within five years of their first period and among women who smoked and had never undergone a full-term pregnancy. This is the link to the new thread -
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08 Jan 2004, 00:14 #7

Smoking linked to breast cancer
BBC News World Edition
Wednesday, 7 January, 2004, 00:36 GMT


Scientists have produced hard evidence that smoking increases the risk of breast cancer.
Previous research has produced mixed results - some has even suggested smoking may have a protective effect.

But a major study of more than 116,000 women by the California Department of Health Services suggests that smoking does pose a significant threat.

The work, which has been challenged by experts, is published in the Journal of the National Cancer Institute.

It does seem that we can now say with some degree of confidence that breast cancer can be added to the ever growing list of serious diseases that can be caused by smoking.
The rate among women who were current smokers was around 30% higher than among those who had never smoked.
Women who started smoking before the age of 20, and those who started at least five years before their first pregnancy appeared to be most at risk.
Breastfeeding is known to help protect against breast cancer, but it might be that exposure to tobacco smoke may undermine this effect.
Heavy smoking or smoking over a long period of time also increased the risk.
However, there was good news for those who had kicked the habit. The researchers found no evidence of a significantly increased risk among former smokers.
There was also no evidence that passive smoking increased the risk of developing cancer.
More work needed
The researchers said more work was required to investigate why smoking might increase the risk of breast cancer.
It is possible that toxins produced by tobacco smoke are stored in the fatty tissues of the breast.
However, they say: "Exposures to tobacco smoke, if causally related to breast cancer, could offer one of the few available modifiable avenues for preventing this disease."
Tobacco is already well known to cause other cancers, most notably lung cancer, as well as other medical problems such as heart disease.
Amanda Sandford, of the anti-smoking charity Action on Smoking and Health, told BBC News Online that it had been harder to prove a link between smoking and breast cancer, than with other cancers.
But she said: "As this is such a big study it does seem that we can now say with some degree of confidence that breast cancer can be added to the ever growing list of serious diseases that can be caused by smoking.
"No organ in the human body is immune to the effects of tobacco smoke, and so it is plausible that cancer could strike anywhere."
Delyth Morgan, breast cancer charity Breakthrough Breast Cancer, said: "A number of studies have investigated the potential link between smoking and breast cancer with conflicting results and more research is needed to clarify a direct association between the two.
"Irrespective of any potential breast cancer risk, smoking is associated with lung and other cancers as well as heart disease and we would strongly advise all women and men not to smoke."
Copyright BBC 2004
Last edited by John (Gold) on 15 Feb 2009, 19:22, edited 1 time in total.
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08 Jan 2004, 00:21 #8

Journal of the National Cancer Institute, Vol. 96, No. 1, 1, January 7, 2004
DOI: 10.1093/jnci/96.1.1
© 2004 Oxford University Press

Press Release
Active Smoking Associated With
Increased Risk of Breast Cancer

Katherine Arnold, News Editor
[url=mailto:jncimedia@oupjournals.org]jncimedia@oupjournals.org[/url]

Active smoking appears to play a larger role in the development of breast cancer than previously thought, according to a study in the January 7 issue of the Journal of the National Cancer Institute.

Tobacco smoke contains a number of human carcinogens, and metabolites of cigarette smoke have been found in the breast fluid of smokers. However, studies examining the association between tobacco smoke and breast cancer risk have yielded inconsistent results. Many studies have not been able to independently assess the contributions of the timing of exposure, age of diagnosis, or genetic susceptibilities to the overall risk of breast cancer. In addition, many of these studies did not consider passive smoking exposures, or exposure to secondhand smoke, among nonsmokers.

Peggy Reynolds, Ph.D., of the California Department of Health Services, and her colleagues examined breast cancer risk among 116,544 women in the California Teachers Study who had reported their smoking status on a survey given to them when they enrolled in the study.

Between 1996 and 2000, 2,005 of the women were diagnosed with invasive breast cancer. The incidence of breast cancer among current smokers was approximately 30% greater than that among women who had never smoked, irrespective of whether they were compared to women who had or had not been exposed to passive smoking. Analysis of subgroups of active smokers revealed increased breast cancer risks among women who started smoking before age 20, who began smoking at least 5 years before their first full-term pregnancy, and who had a longer duration of smoking or who smoked 20 or more cigarettes per day.

Current smoking was associated with increased breast cancer risk in women without a family history of breast cancer but not among women with a family history of the disease. There was no statistically significant increase in breast cancer risk among former smokers, and there was no evidence of an association between passive smoking exposure and breast cancer risk.

"Our results, which suggest that active smoking may be associated with an increased risk of breast cancer, argue for further research that can account for heterogeneity in individual susceptibility," the authors write. "Exposures to tobacco smoke, if causally related to breast cancer, could offer one of the few available modifiable avenues for preventing this disease."

###

Contact: Ken August, California Department of Health Services, 916-440-7660; [url=mailto:kaugust@dhs.ca.gov]kaugust@dhs.ca.gov[/url]
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21 Mar 2004, 07:27 #9

Carcinogenic effect of nicotine on normal mammary ductal epithelial cells and the protective role of beta-carotene.
Indian J Pathol Microbiol. 2003 Jan;46(1):24-7.


Mazhari NJ, Mandal AK, Thusoo TK.

Department of Pathology, Maulana Azad Medical College and associated LNJP Hospital, New Delhi.

A number of carcinogens like polycyclic hydrocarbons and aromatic amines have been incriminated to induce mammary carcinomas in vitro and in vivo. Studies have supported an inter-relationship between tobacco consumption and breast cancer. Because nicotine is the major alkaloid present in tobacco this study was conducted to find the direct in vitro effect of nicotine on normal mammary ductal epithelial cells. It was seen in the present work that nicotine causes a statistically significant increase in the proliferative rate and ER (estrogen receptor) expression as compared to the control group. This change was more pronounced with a lower concentration of nicotine (650 microg/ml). Colony efficiency also showed a similar trend. Beta carotene was added in the present work to study its anti oxidant effect on nicotine induced changes. Beta carotene significantly decreased the proliferation rate induced by 650 microg/ml nicotine. It also prevented the cytotoxic effect of higher dose of nicotine, however, it failed to alter significantly the ER expression induced by lower concentration of nicotine though it showed decreasing trend.

PMID: 15027713 [PubMed - in process]
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04 Mar 2005, 20:28 #10

Smoking Ups Risk of
Premenopausal Breast Cancer
Wed Mar 2, 2005 01:25 PM ET
NEW YORK (Reuters Health) - Both active and "passive" smoking (exposure to secondhand smoke) increase the risk of breast cancer in premenopausal but not postmenopausal women, a study of middle-aged Japanese women suggests.
The investigators think that higher levels of estrogens present in the body of premenopausal women may act jointly with external cancer-causing agents, such as tobacco, to fuel the development of breast cancer.

In the study, Dr. Tomoyuki Hanaoka from the National Cancer Center in Tokyo, Japan, and colleagues studied associations between smoking and breast cancer in close to 22,000 women who were between the ages of 40 and 59 years in 1990.

A total of 180 women developed breast cancer by the end of 1999, they report in the International Journal of Cancer this month.

Among all of the women, 5.7 percent were current smokers, 1.7 percent were ex-smokers, and 92.6 percent had never been active smokers. Sixty-nine percent of these "never-active smokers" reported that they had been exposed to sidestream smoke.

Compared with never-active smokers with no exposure to secondhand smoke, ever-smokers who had yet to enter menopause had a greater than 3-fold elevated risk of developing breast cancer. The elevated risk of developing breast cancer among ever-smokers was not observed in postmenopausal women.

Premenopausal but not postmenopausal women who had never smoked but had been exposed to secondhand smoke had a 2.6-fold increased risk of developing breast cancer.

These results, the authors conclude, show that both active and passive smoking increases the risk of breast cancer in premenopausal women. "Both active and passive smoking are promising targets in the prevention of breast cancer," they write.


SOURCE: International Journal of Cancer March 10, 2005.
© Reuters 2005. All Rights Reserved.
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17 Oct 2008, 22:15 #11

Nicotine induces cell proliferation, invasion and epithelial-mesenchymal transition in a variety of human cancer cell lines.
International Journal of Cancer, October 9, 2008 [Epub ahead of print]

Dasgupta P, Rizwani W, Pillai S, Kinkade R, Kovacs M, Rastogi S, Banerjee S, Carless M, Kim E, Coppola D, Haura E, Chellappan S.
Drug Discovery Program, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL.

Cigarette smoking is strongly correlated with the onset of nonsmall cell lung cancer (NSCLC). Nicotine, an active component of cigarettes, has been found to induce proliferation of lung cancer cell lines. In addition, nicotine can induce angiogenesis and confer resistance to apoptosis. All these events are mediated through the nicotinic acetylcholine receptors (nAChRs) on lung cancer cells. In this study, we demonstrate that nicotine can promote anchorage-independent growth in NSCLCs. In addition, nicotine also induces morphological changes characteristic of a migratory, invasive phenotype in NSCLCs on collagen gel. These morphological changes were similar to those induced by the promigratory growth factor VEGF. The proinvasive effects of nicotine were mediated by alpha7-nAChRs on NSCLCs. RT-PCR analysis showed that the alpha7-nAChRs were also expressed on human breast cancer and pancreatic cancer cell lines. Nicotine was found to promote proliferation and invasion in human breast cancer. The proinvasive effects of nicotine were mediated via a nAChR, Src and calcium-dependent signaling pathway in breast cancer cells. In a similar fashion, nicotine could also induce proliferation and invasion of Aspc1 pancreatic cancer cells. Most importantly, nicotine could induce changes in gene expression consistent with epithelial to mesenchymal transition (EMT), characterized by reduction of epithelial markers like E-cadherin expression, ZO-1 staining and concomitant increase in levels of mesenchymal proteins like vimentin and fibronectin in human breast and lung cancer cells. Therefore, it is probable that the ability of nicotine to induce invasion and EMT may contribute to the progression of breast and lung cancers. (c) 2008 Wiley-Liss, Inc.
PMID: 18844224 [PubMed - as supplied by publisher]

Link to Abstract: http://www.ncbi.nlm.nih.gov/pubmed/18844224


Nicotine Promotes Mammary Tumor Migration via a Signaling Cascade Involving Protein Kinase C and cdc42

Cancer Research 68, 8473-8481, October 15, 2008. doi: 10.1158/0008-5472.CAN-08-0131

Jinjin Guo1, Soichiro Ibaragi2, Tongbo Zhu1, Ling-Yu Luo1, Guo-Fu Hu2, Petra S. Huppi3 and Chang Yan Chen1
1 Department of Radiation Oncology, Beth Israel Deaconess Medical Center and 2 Department of Pathology, Harvard Medical School, Boston, Massachusetts and 3 Department of Pediatrics, University of Geneva, Geneva, Switzerland
Requests for reprints: Chang Yan Chen, Department of Radiation Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, 21-27 Burlington Avenue, Room 553C, Boston, MA 02215. Phone: 617-632-8513; Fax: 617-632-0635; E-mail: [url=mailto:cchen6@bidmc.harvard.edu]cchen6@bidmc.harvard.edu[/url] .
Nicotine, one of the major components in tobacco, is at high concentrations in the bloodstream of cigarette smokers. However, the mechanisms of how nicotine affects tumor development and whether nicotine is a potential carcinogen for malignancies induced by secondhand smoking are not fully understood yet. Here, we investigate the signaling pathways by which nicotine potentiates tumorigenesis in human mammary epithelial-like MCF10A or cancerous MCF7 cells. We show that human MCF10A and MCF7 cells both express four subunits of nicotine acetylcholine receptor (nAChR). The treatment of these cells with nicotine enhances the activity of protein kinase C (PKC) [alpha] without altering the expression level of this kinase. Nicotine also stimulates [3H]thymidine incorporation into the genome of these cells as well as forces serum-starved cells to enter S phase of the cell cycle, resulting in growth promotion. Importantly, on nicotine treatment, the mobility of MCF10A and MCF7 cells is enhanced, which can be blocked by the addition of nAChR or PKC inhibitor. Experiments using small interfering RNA knockdown or ectopic expression of cdc42 showed that cdc42 functions as a downstream effector of PKC and is crucial in the regulation of nicotine-mediated migratory activity in the cells. Together, our findings suggest that nicotine, through interacting with its receptor, initiates a signaling cascade that involves PKC and cdc42 and consequently promotes migration in mammary epithelial or tumor cells.
http://cancerres.aacrjournals.org/cgi/c ... 68/20/8473
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29 Jul 2010, 18:13 #12

Researchers find firm link between nicotine, cancer

Thursday, July 29, 2010 -  CNA
TAIPEI -- There is no doubt that smoking or the inhalation of second-hand cigarette smoke can cause breast cancer, Taiwan researchers said yesterday, citing their recent findings in a study on smoking and breast cancer. The study found that a receptor, known as alpha 9 (a9), on breast tissue cells is very sensitive to nicotine.

With a constant nicotine stimulus, the receptor can transform a normal cell into a cancer cell, said professor Ho Yuan-soon of Taipei Medical University's School of Medical Laboratory Science and Biotechnology.

In turn, "the stimulated cell automatically produces more a9," Ho explained. "Gradually the receptor triggers the cell's transformation and the proliferation of a tumor."

When the stimulated cell was planted in the body of laboratory mice with immunodeficiency, cancer cells proliferated rapidly, "as if they were fueled," the researchers said.

The research team then sought to stem the a9 activity by means of gene modification, which resulted in an obvious shrinking of the tumors, Wu said.

The study, which was done on tissue samples from 267 breast cancer patients in Taiwan, found that in the cases of the women who smoked heavily, the a9 receptor was two to three times more active than in those who did not smoke, Wu said.

The more active the a9 receptor, the more aggressive the breast cancer, Wu said.

The study proved a direct link between breast cancer and smoking, the researchers said.

It also located the biomolecule target for the future development of breast cancer cures, according to the research team.

The study will be published in the U.S. journal of the National Cancer Institute on Sept. 8.



Copyright © 1999 – 2010 The China Post.
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29 Jul 2010, 20:24 #13

Yikes, it just keeps coming and coming! Thanks for the information.

Mike
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24 Aug 2010, 11:13 #14

Nicotine binding to receptor linked to breast cancer cell growth When nicotine binds to the nicotinic acetylcholine receptor (nAchR), it is known to promote smoking addiction and may also directly promote the development of breast cancer, according to a study published online August 23 in The Journal of the National Cancer Institute.

While smoking is a well-known risk factor for a broad range of cancer types, non-nicotine components of tobacco have generally been thought to be the carcinogens, so little is known about how nicotine acts on cells to promote cancer cell growth. For breast cancer in particular, some large epidemiological studies have suggested that smoking is related to increased breast cancer risk, but they have not been accompanied by molecular biology studies on how that actually works.

To determine whether nicotine works on the cellular level to promote breast cancer growth, Yuan-Soon Ho, Ph.D., of the Taipei Medical University, and colleagues, looked at 276 breast tumor samples from anonymous donors to the Taipei Medical University Hospital, to see whether subunits of the nicotinic acetylcholine receptor were overexpressed in breast cancer cells compared with surrounding normal cells.

The researchers found that human breast cancer cells consistently overexpressed the alpha 9 subunit of the nAChR (α9-nAchR), and that expression was higher in advanced-stage breast cancer compared with early-stage cancer. They also found that reducing the levels of α9-nAchRs inhibited tumor growth in laboratory experiments, whereas increasing the levels of α9-nAchRs or treating more normal breast cells with nicotine promoted the development of cancer characteristics.

The authors write: "These results imply that receptor-mediated carcinogenic signals play a decisive role in biological functions related to human breast cancer development."

The authors say their study was limited by its small sample size, and the fact that it included only Asian patients. Breast cancer in Taiwan is characterized by its low incidence rate and early stage of tumor onset.

In an accompanying editorial, Ilona Linnoila, M.D., of the Center for Cancer Research at the National Cancer Institute, writes that the study "suggests not only that smoking could be causally related to breast carcinogenesis but also that nicotine could directly contribute to the molecular mechanism of carcinogenesis in addition to indirectly contributing by promoting addiction to smoking."

Furthermore, Linnoila writes, "Better understanding of the molecular mechanisms of the cholinergic pathways will lead to more opportunities for intervention and prevention of tobacco toxicity."


###
Contact

Article: Yuan-Soon Ho, 011-886-2-27361661 ext 3327, [url=mailto:hoyuansn@tmu.edu.tw]hoyuansn@tmu.edu.tw[/url]
Editorial: Office of Media Relations, the National Cancer Institute, 301-496-6641, [url=mailto:NCIPressOfficers@mail.nihi.gov]NCIPressOfficers@mail.nihi.gov[/url]


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07 Oct 2010, 13:09 #15

Nicotine linked to breast
cancer risk, study finds

By Dr. Patricia Limpert | Posted: Wednesday, October 6, 2010 2:30 pm

According to a recent Kaiser Family Foundation study, 22.8 percent of Missouri women and 17.5 percent of Illinois women are smokers, which is higher than the national average of 16.2 percent.

And while about 60 percent of those women have attempted to quit at one time or another, they have yet to kick the habit. There are many reasons to stop smoking, but a recent study published in the Journal of the National Cancer Institute may give women another reason not to light up. Researchers have suspected for a long time that smoking increases the risk of breast cancer, but that risk is typically associated with other carcinogens in cigarettes, rather than nicotine. However, this study took a closer look at nicotine specifically, and it found a clear association with breast cancer risk.

The study examined human breast cancer tumors and found the cells had large numbers of receptors which nicotine was able to attach to when compared with normal cells. They also found that when normal cells were treated with nicotine, nicotine promoted the development of cancer characteristics.

Interestingly, the study also found that women who smoke and use hormone replacement therapy containing estrogen and progestins have twice the risk of developing breast cancer compared to nonsmoking women on hormone replacement therapy.

Even if women do not smoke, they still could be putting themselves and their babies at risk. Studies have found women who are exposed to cigarette smoke have nicotine traces in their breast milk. Avoidance of secondhand smoke becomes that much more important for expectant mothers who live or associate with someone who smokes.

These findings only add to other known risks for women who smoke. Those include increased risk of lung cancer, oral cancers, cervical and vulvar cancers, blood clots, high blood pressure, stroke, heart attack, osteoporosis and fractures of the hip and spine, infertility, abnormal menstruation, early onset of menopause and respiratory diseases including asthma and emphysema.

Those who quit smoking experience immediate and long-term benefits including improved circulation, lowered blood pressure and a lower risk of developing cancer as each year passes. For more information on the risks of smoking or to find resources on how to quit, visit smokefree.gov


Dr. Patricia Limpert is a breast surgeon at the Breast Care Center at St. Luke's Hospital. Call 314-205-6491 or visit stlukes-stl.com. XX Files, a women's health column, rotates each week with Aging Successfully, a column for seniors by Dr. John Morley of St. Louis University.
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31 Jan 2012, 13:09 #16


"Quit Quarter" to reduce smoking

Maya Akbay - The Toronto Observer  -  Published 31 January 2012
A Scarborough doctor wants the Royal Canadian Mint’s support in the battle against smoking.

According to Health Canada, smoking remains the number one cause of preventable deaths in Canada. Dr. John Oyston of Scarborough General Hospital hopes to stop the addiction right where it starts – in adolescents.
“Kids don’t see the warning labels, because they never see the packets, they just get single cigarettes off their friends.”     - Dr. John Oyston
He launched a campaign at the start of National No Smoking Week on Jan. 15 to get the Royal Canadian Mint to produce a “Quit Quarter” that is specifically designed to help quit smoking. He hopes a Quit Quarter would especially encourage teenagers getting allowance from their parents to reconsider where they spend their money.

“Kids don’t see the warning labels, because they never see the packets, they just get single cigarettes off their friends,” said Oyston.

“When you start buying cigarettes for yourself, that’s when you’re close to being hooked. At that stage, if you’re digging into your pocket for change and there’s a Quit Quarter there, that’s just another reminder that it all goes back to your health.”

As an anesthesiologist, Oyston sees the damage that smoking does to his patients.

“It’s funny, breast cancer is what people think about when they think of women dying of cancer,” said Oyston. “But more women die from breast cancer due to cigarette smoking than anything else.”

“Maybe in the 50s and 60s, women started smoking and it became acceptable. Now 50 years later, rates for women dying from lung cancer is going up.”

It was the breast cancer awareness coin that sparked the idea in Oyston’s head.

“What’s the purpose of having a coin with a pink ribbon on it? How do you use that to stop getting breast cancer?” Oyston asked.

“You buy cigarettes with money, right?” he added, “So it’s much easier to avoid getting addicted to cigarettes than it is to avoid getting breast cancer.”

The Royal Canadian Mint is “officially thinking about it” while several organizations such as the Canadian Pharmacists Association and the Heart and Stroke Foundation of Ontario have shown their support for the idea.

“I’m just a doctor … If I write to the prime minister, which I did, I don’t get a reply,” said Oyston. “I just need an organization like the Canadian Cancer Society on my side, and a retail chain. So that’s what I’m looking at next.”

What if his teenage son, who pitched a design for the coin himself, started smoking?

“I think the likelihood of that happening is pretty slim!” laughed Oyston. There are no smokers in the family, given the circumstances.
Copyright The Toronto Observer 2012 -  All Rights Reserved
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