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Old 07-13-2010, 04:34 PM
Dross Dross is offline
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Default Smoking influences gene function, scientists say

SAN ANTONIO, July 13, 2010 – In the largest study of its kind, researchers at the Southwest Foundation for Biomedical Research (SFBR) have found that exposure to cigarette smoke can alter gene expression -- the process by which a gene's information is converted into the structures and functions of a cell. These alterations in response to smoking appear to have a wide-ranging negative influence on the immune system, and a strong involvement in processes related to cancer, cell death and metabolism.

The scientists indentified 323 unique genes whose expression levels were significantly correlated with smoking behavior in their study of 1,240 people. The changes were detected by studying the activity of genes within white blood cells of study participants.

"Our results indicate that not only individual genes but entire networks of gene interaction are influenced by cigarette smoking," wrote lead author Jac Charlesworth, Ph.D., in the July 15 issue of the open access journal BMC Medical Genomics. Charlesworth, formerly at SFBR, is now a research fellow at the Menzies Research Institute at the University of Tasmania in Australia.

The study was funded by the National Institutes of Health and the Azar and Shepperd families of San Antonio, ChemGenex Pharmaceuticals and the AT&T Foundation. The study is part of SFBR's San Antonio Family Heart Study (SAFHS) which includes 40 families in the Mexican American community.

"Previous studies of gene expression as influenced by smoking have been seriously limited in size with the largest of the in vivo studies including only 42 smokers and 43 non-smokers. We studied 1,240 individuals, including 297 current smokers" Charlesworth said. "Never before has such a clear link between smoking and transcriptomics been revealed, and the scale at which exposure to cigarette smoke appears to influence the expression levels of our genes is sobering".

"Our results indicate that not only individual genes but entire networks of gene interaction are influenced by cigarette smoking. It is likely that this observed effect of smoking on transcription has larger implications for human disease risk, especially in relation to the increased risk of a wide variety of cancers throughout the body as a result of cigarette smoke exposure," Charlesworth said.

Last edited by gdpawel : 01-23-2012 at 02:45 PM. Reason: post full article
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Old 07-20-2010, 02:12 PM
gdpawel gdpawel is offline
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Default Lung Cancer and Smoking Cessation

"Since a substantial number of patients presenting with lung cancer either smoked in the recent past or continue to do so, it is important to make sure that the patient stops smoking as soon as possible to improve their treatment outcome," says Dr. Carolyn M. Dresler, Head, Tobacco and Cancer Group of the International Agency for Research on Cancer. She added, "the emphasis should be on improvement of treatment outcome and future health improvement."

There are guidelines regarding smoking cessation techniques that have resulted from reviews of the world's literature and are very well accepted throughout the medical and psychological fields. However, "the biggest problem remains in having healthcare providers implement them routinely," Dr. Dresler says, "Most have emphasized the role of the primary healthcare provider in providing smoking cessaton advice to patients, whereas the specialists, such as medical oncologists, radiation oncologists, thoracic surgeons or pulmonary care specialists should be dealing with the health problems resulting from the smoking as the patient faces imminent interventions such as radiation therapy, chemotherapy or surgery."

She makes the point that since ongoing smoking may significantly affect the outcome of subsequent surgery or therapy and negatively impact long-term survival, it is now the specialists' turn to provide the urgent smoking cessation treatment. With the advent of medicare changes under the new Medicare Modernization Act (MMA), the specialists will be reimbursed for providing evaluation and management services, making referrels for diagnostic testing, radiation therapy, surgery and other procedures as necessary, and offer any other support needed to reduce patient morbidity and extend patient survival. I certainly hope they add smoking cessation guidance and support.

Source: (Cancer Epidemiol Biomarkers Prev 2005;14(10):2287–93)

[url]www.treatobacco.net is an evidence-based site containing information in 11 languages on tobacco dependence treatment relative to efficacy, safety, demographics and health effects, health economics, and policy.

[url]www.cdc.gov/tobacco/ is a site to let you know everything you wanted to know about tobacco at the CDC.

[url]www.guideline.gov/summary/summary.aspx?doc_id=2958&nbr=2184 is the National Guideline Clearinghouse web site for smoking cessation.
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Old 07-20-2010, 02:17 PM
gdpawel gdpawel is offline
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Default Lung Cancer and Smoking Cessation

No "pharmaceutical" trial ever followed whether patients smoked during their clinical trials, despite dosing themselves daily with cigarettes with hundreds chemicals in them. Dr. Dresler stated that "the addition of nicotine inhibits the ability of a chemo drug (like etoposide) to induce apoptosis by 61%." If a drug like nicotine, which occurs in the highest concentration of any drug in a cigarette, inhibits the ability of a major chemotherapy drug by 61%, a medical oncologist should care if it was being ingested during treatment.

In the article, "Smoking, The Missing Drug Interaction in Clinical Trials: Ignoring the Obvious" (Cancer Epidemiol Biomarkers Prev 2005;14(10):2287?93), Dr. Dresler and her colleagues concluded that we can no longer ignore the obvious: smoking is a critical variable that affects cancer treatment and outcome and has been shown to vitiate or interact with the effects of some therapeutic agents and chemopreventive agents. Measurement of smoking history and status in clinical trials of cancer therapy will increase our knowledge of the adverse effects of the constituents of tobacco smoke, including nicotine, and of drug interactions.

Oncology health professionals have called for increased advocacy for tobacco control. Furthermore, the routine inclusion of smoking status and cessation need to become a standard of care for all patients. The inclusion of smoking data in oncology clinical trials will also provide clinicians with improved means of delivering individualized advice to patients with cancer that may be critical in motivating their cessation efforts and sustained abstinence.

Scientific, financial, and clinical support is critical to this goal. The failure to date to assess, analyze, and report smoking status has limited our ability to investigate the effect of smoking on treatment efficacy and outcome. The time has come to integrate data about the single most important lifestyle risk factor in cancer prevention into cancer treatment and survivorship trials.
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Old 09-06-2010, 10:22 AM
gdpawel gdpawel is offline
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Default Medicare to pay for counseling for senior smokers who are not yet sick

According to an article by Merrill Goozner at The Fiscal Times, Medicare leveled a pre-emptive strike against smoking and agreed to pay for counseling for senior smokers who are not yet sick. The new smoking cessation program for seniors might seem a tad late. People usually smoke for decades before they get cancer, emphysema, heart disease and other smoking-related disorders - just in time for Medicare to pick up the tab. But the Center for Medicare and Medicaid Services (CMS) decision memo noted that even older smokers who quit can see fairly quick payback in terms of reduced illness.

Smoking costs the U.S. economy $97 billion annually in lost productivity, in addition to the $96 billion a year in direct health care costs, according to CMS. Counseling coupled with smoking prevention drugs and devices are among the most cost-effective interventions in the disease prevention arsenal.

A Rand Corporation analysis of a Medicare demonstration projection estimated the total health care cost savings for the agency exceeded payments for the smoking cessation program within five years. “The cost of these programs may be offset by reductions in medical expenses even when targeting older smokers,” the researchers concluded.

CMS began paying for counseling for seniors already sick with smoking-related illnesses in 2005. It will now pay for four private counseling sessions during two attempts a year for people trying to quit. “The practitioner and patient have the flexibility to choose between intermediate (more than three minutes) or intensive (more than ten minutes) cession counseling sessions for each attempt,” the agency ruled.

[url]http://www.thefiscaltimes.com/Issues/Health-Care/2010/09/01/Medicare-A-New-Way-to-Lower-Costs.aspx
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Old 03-20-2011, 01:37 PM
gdpawel gdpawel is offline
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Default Smoking influences

Back in 1980, the NCI lung cancer section published a paper showing that smokers with lung cancer who quit smoking at diagnosis lived longer than those who continued to smoke (See JAMA study below #3).

Since then, one paper was published which didn't agree (#2), while another was published which did agree (#1). Note 23 years since #3 was published, and there is still no clear cut agreement (unless you consider 2 out of 3 to be sufficient to settle the issue). This all goes to show how imprudent it is to consider a relatively trivial issue either unproven or settled, based on published clinical trials.

1: J Clin Oncol. 2003 Apr 15;21(8):1544-9.

Continued cigarette smoking by patients receiving concurrent chemoradiotherapy for limited-stage small-cell lung cancer is associated with decreased survival.

Videtic GM, Stitt LW, Dar AR, Kocha WI, Tomiak AT, Truong PT, Vincent MD, Yu EW.

Department of Radiation Oncology, Brigham and Women's Hospital, 75 Francis St, ASBI, L2, Boston, MA 02115, USA. [email]gvidetic@lroc.harvard.edu[/email]

PURPOSE: To determine the impact of continued smoking by patients receiving chemotherapy (CHT) and radiotherapy (RT) for limited-stage small-cell lung cancer (LSCLC) on toxicity and survival.

PATIENTS AND METHODS: A retrospective review was carried out on 215 patients with LSCLC treated between 1989 and 1999. Treatment consisted of six cycles of alternating cyclophosphamide, doxorubicin, vincristine and etoposide, cisplatin (EP). Thoracic RT was concurrent with EP (cycle 2 or 3) only. Patients were known smokers, with their smoking status recorded at the start of chemoradiotherapy (CHT/RT). RT interruption during concurrent CHT/RT was used as the marker for treatment toxicity.

RESULTS: Of 215 patients, smoking status was recorded for 186 patients (86.5%), with 79 (42%) continuing to smoke and 107 (58%) abstaining during CHT/RT. RT interruptions were recorded in 38 patients (20.5%), with a median duration of 5 days (range, 1to 18 days). Median survival for former smokers was greater than for continuing smokers (18 v 13.6 months), with 5-year actuarial overall survival of 8.9% versus 4%, respectively (log-rank P =.0017). Proportion of noncancer deaths was comparable between the two cohorts. Continuing smokers did not have a greater incidence of toxicity-related treatment breaks (P =.49), but those who continued to smoke and also experienced a treatment break had the poorest overall survival (median, 13.4 months; log-rank P =.0014).

CONCLUSION: LSCLC patients who continue to smoke during CHT/RT have poorer survival rates than those who do not. Smoking did not have an impact on the rate of treatment interruptions attributed to toxicity.

2: Eur Respir J. 1988 Dec;1(10):932-7.

Erratum in: Eur Respir J 1989 Jun;2(6):following 591.

Smoking and effect of chemotherapy in small cell lung cancer.

Bergman B, Sorenson S. Dept. of Pulmonary Medicine, Renstromska Hospital, Goteborg University, Sweden.

The relationship between smoking habits and outcome of treatment was studied in 154 patients with small cell lung cancer (SCLC) who received combination chemotherapy. Thirty-two patients had stopped smoking at least 6 months before the initiation of treatment or had never smoked (NS), 51 patients stopped smoking less than 6 months prior to the start of treatment (SS) and 71 patients continued to smoke during the treatment period (CS). Life table analysis of overall survival showed no significant heterogeneity among the groups (p greater than 0.7). Chi-square test for trend in survival yielded 0.23 (p greater than 0.6) with the longest survival in SS and CS patients, and the shortest survival in NS patients. Corresponding analysis of time to progression showed similar results, with a non-significant heterogeneity (p greater than 0.5) and trend (p greater than 0.4) among the three groups, with the CS patients doing best.

In the whole series the disease-free two-year survival rate was higher in the CS patients than in the SS and NS patients (p = 0.04). The results do not imply that continued smoking during chemotherapy in SCLC has unfavourable effects on the outcome of treatment.

3: JAMA. 1980 Nov 14;244(19):2175-9.

Smoking abstinence and small cell lung cancer survival. An association.

Johnston-Early A, Cohen MH, Minna JD, Paxton LM, Fossieck BE Jr, Ihde DC, Bunn PA Jr, Matthews MJ, Makuch R.

The prognostic implications of cigarette smoking were investigated in 112 patients with small cell lung cancer. Twenty had stopped smoking permanently before diagnosis (NS-Prior), 35 had stopped at diagnosis (NS-Dx), and 57 patients continued smoking (S). Therapies included chemotherapy alone or with radiation therapy, with or without thymosin fraction V. The survival difference among the three groups was statistically significant. The NS-Prior patients had the best survival, followed by NS-Dx patients and finally S patients. No S patient has survived, disease free, more than 96 weeks, while three NS-Prior and three NS-Dx patients are disease free 103 to 220 weeks after start of treatment. Thymosin, 60 mg/sq m, yielded survival benefits for the S group only. Continuation of smoking during the treatment of small cell lung cancer was associated with a poor prognosis, while discontinuation of smoking, even at diagnosis, may have beneficial effects on survival.
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Old 01-23-2012, 03:00 PM
gdpawel gdpawel is offline
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Default Many keep smoking after cancer diagnosis?

According to a new study in the American Cancer Society journal CANCER, researchers looked at 2,456 lung cancer patients and 3,063 colorectal patients and discovered that at time of diagnosis, 38% of the lung cancer patients and 15% of the colorectal patients were smokers.

Five months later, despite a cancer diagnosis, 14% of the lung cancer patients were still lighting up (and 9% of the colorectal patients).

"People think it's a no-brainer and are surprised that cancer patients continue to smoke after they're diagnosed," says Elyse R. Park, a clinical health psychologist and associate professor of psychiatry at Massachusetts General Hospital/Harvard Medical School and lead researcher for the study. "But people still struggle to quit even after they're diagnosed. There are a lot of barriers to quitting, including a lot of stigma."

Park says many of the people who can't quit are "hard-core" smokers, i.e., they smoke a high number of cigarettes a day. Many, also, are surrounded by other smokers.

"These people are nicotine addicted, so it's tough for them," says Park. "They also have a lot of self-blame for causing the disease. There are feelings of fatalism. They think, 'Why stop now?' And a lot of people are very judgmental about lung cancer patients causing their own disease."

According to the Lung Cancer Foundation of America, 60% of new lung cancer diagnoses happen to non-smokers, 15% of whom have never smoked a day in their life (the rest are former smokers who quit 10, 20 or even 30 years prior to diagnosis).

The American Lung Association estimates that active smoking is responsible for close to 90% of lung cancer cases; radon causes 10%, and occupational exposures to carcinogens account for approximately 9 to 15%.

Park says she hopes her study will pave the way for more smoking cessation programs and treatment options for patients who are smoking at the time of their diagnosis.

"One of the reasons it's hard to quit is that people think they have enough to worry about," she says. "But it's the best time to quit because it has the potential to improve their cancer treatment, from breathing easier and feeling less fatigue to reducing the chance of infection after surgery."

Parks says studies also show that quitting smoking can increase the efficacy of chemo and radiation and may even double the chances of survival for lung cancer patients.

"We're hoping to integrate evidence-based tobacco treatment into cancer care," she says. "So you don't just ask a patient, 'Do you smoke, yes or no?' But you try to get them to quit as part of their treatment. It's a tough time, but we're hoping to find ways to sit with patients and get them pharmacological and behavior counseling treatment."

Source: American Cancer Society
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