Group Research Topics

Our objective is to bring as much scientific evidence as possible to bear on the identification and characterization of the causes of cancer. This grant supports the nucleus of a team involved in epidemiologic research on environmental and lifestyle causes of cancer. Several large data bases have been established and are being analysed. New opportunities for setting up relevant data collections are being investigated. We are also vigilant about research opportunities that arise because of some unique exposure circumstances or because of legitimate concerns expressed by citizens, government agencies or other groups.

Contents:

1. Occupational and selected non-occupational risk factors for lung cancer: analysis of a case-control study in Montréal
2. INTEROCC – Occupational exposure to EMF in different frequency bands and selected chemical exposures in relation to risk of glioma and meningioma
3. SYNERGY – Pooled Analysis of Case-Control Studies on the Joint Effects of Occupational Carcinogens in the Development of Lung Cancer: Montreal Component
4. Occupational and Lifestyle factors in etiology of prostate cancer, and establishing a platform for studying susceptibility biomarkers
5. New survival analytic methods for time-dependent exposures in case-control studies, with applications to cancer
6. To develop and validate multivariable lung cancer incidence and prevalence models.
7. A computer-based tool to help assess health risk posed by exposure to chemicals through the skin
8. GENESIS PRAXY: GENdEr and Sex DetermInantS of Cardiovascular Disease: From Bench to Beyond PRemature Acute Coronary SYndrome.
9. Effect modification of gene-mediated susceptibility to myocardial infarction by sex and other conventional coronary risk factors.
10. Investigating the role of the built environment in the development and maintenance of excess weight in a cohort of children at risk for obesity
11. Gene-environment interaction study of postmenopausal breast cancer

Jack Siemiatycki (PI); Parent M.-É., Rousseau M.-C., Abrahamowicz M., Leffondré K., Case B., Krewski D

A large case-control study of lung cancer was conducted in Montreal between 1996 and 2000. The methodology was built on a ground-breaking multi-cancer study conducted by Jack Siemiatycki earlier in his career. The key innovative aspect involves obtaining a detailed occupational history from all participants which is subsequently evaluated by a team of industrial hygienists and chemists. Their task is to infer likelihood of exposure to a list of nearly 300 chemicals for each study participant for each job held. This grant will allow us to conduct multiple parallel sets of analyses that will elucidate the relationship between lung cancer and hundreds of occupational chemicals and other classes of variables such as alcohol consumption, smoking behaviour home heating, ethnicity and others.

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INTEROCC – Occupational exposure to EMF in different frequency bands and selected chemical exposures in relation to risk of glioma and meningioma

Elisabeth Cardis (PI); Jack Siemiatycki; Marie-Elise Parent

The current project aims to exploit the information on occupational exposures collected within the INTERPHONE study, a multi-national case-control study of the possible association between use of cellular telephones and cancer risk. It has two specific substantive aims:

(1)   To evaluate the possible association between occupational exposure to EMF in different frequency bands and tumors of the brain and central nervous system (specifically, glioma and meningioma).

(2)   To evaluate the possible association between selected occupational chemical exposures and tumors of the brain and central nervous system (specifically, glioma and meningioma).

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SYNERGY – Pooled Analysis of Case-Control Studies on the Joint Effects of Occupational Carcinogens in the Development of Lung Cancer: Montreal Component

Anita Koushik(PI), Jack Siemiatycki; Michel Gérin; Jérôme Lavoué·; Marie-Elise Parent·; Kurt Straif·; Paolo Boffetta·; Ann Olsson

At a given job or during their occupational history many workers are exposed to more than just one carcinogen. The synergistic effects of these carcinogens on the development of lung cancer are largely unknown. This gap in knowledge impedes more efficient primary prevention and fair compensation of diseased workers. Within the last decade, several epidemiological studies have been conducted on risk factors for the development of lung cancer. In 2006 funds were obtained to set up the SYNERGY project involving eight European centres and coordinated by the International Agency for Research on Cancer. The data from a Montreal lung cancer study (1,200 cases and 1,400 controls ) will be included in this pooled analysis of European lung cancer studies, to assess the risk of lung cancer in workers exposed to more than one occupational lung carcinogen.

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Marie-Elise Parent (PI); Jack Siemiatycki; Mark Goldberg; Chokkalingam A., Aprikian A., Saad F., Karakiewicz P

Prostate cancer continues to be the most frequently occurring cancer among Canadian men and it is anticipated that its overall incidence will continue to rise. Although prostate cancer is referred to as a cancer with a very good prognosis, many cancer survivors will have to cope, as a result of their disease or treatment, with lasting side effects impairing seriously their quality of life. The unfavourable circumstances following prostate cancer diagnoses therefore clearly highlight the need to find ways to prevent this disease which, in turn, means identifying modifiable risk factors.

Efforts to elucidate the risk factors for prostate cancer have met with little success to date. The descriptive epidemiology provides compelling evidence that its etiology involves environmental influences. Occupational agents and lifestyle represent potential risk factors that are both promising and under-studied. Moreover, susceptibility genes are at the cutting edge of prostate cancer research. In this study, we are exploring, using expert-based exposure assessment, the role of some 100 occupational substances under particular suspicion, including several hormone modulators. In addition, we are assessing the role of several lifestyle characteristics for which more evidence needs to be accrued.

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Karen Leffondré (PI); Jack Siemiatycki

This project aims to develop new methods of survival analysis for assessing the impact of time-dependent covariates in case-control studies, and to apply them to several real-life date sets.

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A computer-based tool to help assess health risk posed by exposure to chemicals through the skin

Jérôme Lavoué (PI)

Few tools are available to help occupational health practitioners in assessing potential risk posed by exposure to chemicals through the skin. The ‘skin notation’ system, currently proposed by many organizations that set occupational exposure limits, simply flag chemicals with a potential for skin absorption and subsequent toxic effects. The rationale behind the attribution of skin notations has been assessed as often vague or based on variable information. This project aims at creating a computer-based tool providing in a transparent way all relevant information about toxicity and potential for cutaneous absorption. It will also include a risk index based on estimation of the percutaneous absorption rate with QSAR models and uncertainty analysis using Monte Carlo methods.

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Tracie Barnett (PI); Anita Koushik

The overarching aim is to identify characteristics of residential and school environments that most strongly influence adiposity, fitness, and related behaviours (physical activity, sedentary behaviour, dietary behaviour) in children at risk of obesity due to their parental history. Outcomes are already being assessed at baseline and 2 year follow-up as part of the QUALITY study, a population-based cohort study investigating the natural history of excess weight in children aged 8-10 years. Funding to investigate aspects of residential and neighborhood environments has recently been obtained; the purpose of the current proposal is to collect complementary data on school environments. In this study, attributes of school features and policies will be assessed, and the extent to which these influence weight status, and behaviours that influence weight status, will be examined. We will also examine how these primary relationships are affected by child’s gender, attitudes, and beliefs; parental modeling and support of healthy behaviours; and neighbourhood social environment. It has become urgent to address the current pediatric obesity crisis; in partnership with community, schoolboard, and public health representatives, this study will identify health promotion targets designed to create healthy school environments that support healthy choices.

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Anita Koushik (PI), Jack Siemiatycki, Michal Abrahamowicz, Anne-Marie Mes-Masson, Diane Provencher, Edgard Delvin, Marie-Pierre Dubé

Ovarian cancer is the fifth leading cause of cancer death among Canadian women and ranks as the most lethal of the gynecological malignancies. The high case-fatality is a consequence of the advanced stage at which ovarian cancer is usually diagnosed. Unfortunately, early symptoms are vague and not easily recognized. Furthermore, effective measures to screen for early disease currently do not exist. Primary prevention thus offers the most promising approach to reducing the morbidity and mortality associated with this deadly disease. Established preventive factors for ovarian cancer include high parity, long duration of lactation, oral contraceptive use and tubal ligation. However, the ability to modify these reproductive factors is limited. There is suggestive evidence that modifiable factors in the vitamin D pathway (sun exposure, diet) and inflammation pathway (anti-inflammatory medication use, talc use for feminine hygiene) may play a role in ovarian cancer risk, though this research has been limited by small sample sizes, crude exposure measurement and lack of control for important confounders. In this study, we are assessing vitamin D and inflammation exposures, in addition to other lifestyle factors, to identify possible modifiable factors that can contribute to ovarian cancer prevention.