Factors Associated With the Prevalence of Prostate Cancer in Rural Saskatchewan: The Saskatchewan Rural Health Study

Unmasking the Hidden Danger: A Decade-Long Systematic Review of Case-Control Studies on Single Occupational Risks and Prostate Cancer

The present systematic review addresses the influence of occupational exposures on prostate cancer risk. Eleven studies were analyzed for a range of occupational exposures, including but not limited to firefighting, physical activity, night shift work, chemical exposure, and solar ultraviolet radiation. The results of the review reveal that firefighters exposed to harmful substances, individuals engaged in physically strenuous work, and workers with chronic night shift routines showed an increased likelihood of developing prostate cancer. Moreover, the review identified an increased risk associated with exposure to certain chemicals, including alkylphenolic compounds and benzene-related substances. The evidence underscores the importance of considering the cumulative effect of multiple risk factors in a comprehensive risk assessment. However, the conclusions indicate the necessity for further research to deepen these relationships and develop more effective strategies for the prevention of prostate cancer.

Prevalence of Hormone-Related Cancers (HRCs) at Two-Time Points in Rural Saskatchewan: The Saskatchewan Rural Health Study (SRHS)

OBJECTIVE

This study aimed to determine the prevalence of hormone-related cancers (HRCs) among Saskatchewan rural dwellers and explore associated risk factors.

METHODS

Data were analyzed from the Saskatchewan Rural Health Study (SRHS), which was a prospective cohort (2010 to 2014). Completed questionnaires were obtained from 4624 (2797) households, with information about 8261 (4867) individuals more than or equal to 18 years at baseline (follow-up). The crude prevalence of HRCs was calculated using appropriate formulae. Adjusted prevalence was calculated using logistic regression based on the generalized estimating equation (GEE).

RESULTS

Crude prevalence of HRCs was 3.0% at the baseline. Variables significantly associated with HRCs were: exposure to radiation comprising ultraviolet radiation from sunlight as well as ionizing radiation (odds ratio [OR] 3.39; 95% confidence interval [CI]: 2.23, 4.84), previous history of cancer in sibling (OR = 1.51, 95% CI: 1.11, 2.07) and in father (OR = 1.37; 95% CI = 1.01, 1.86).

CONCLUSIONS

The study informs the Saskatchewan Health Region for health care resource allocation.

Pesticide exposure and cancer: an integrative literature review

ABSTRACT We conducted an integrative literature review of published studies on pesticide and cancer exposure, focusing on farmers, rural population, pesticide applicators, and rural workers. The Medline/PubMed was used as searching database. After the retrieval, 74 articles were selected according to pre-established criteria, which design involved 39 case-controls, 32 cohorts, 2 ecological ones, and 1 cross-sectional. Among them, 64 studies showed associations between pesticides and cancer while 10 did not find any significant association. The studies found 53 different types of pesticides significantly associated with at least one type of cancer and 19 different types of cancers linked to at least one type of pesticide. Although few studies presented contradictory results, the sole fact of being a farmer or living near crops or high agricultural areas have also been used as a proxy for pesticide exposure and significantly associated with higher cancer risk. The literature well illustrates the case of prostate cancer, Non-Hodgkin lymphoma, leukemia, multiple myeloma, bladder and colon cancers. Studies are recommended to further investigate the relationship between pesticide and neoplasm of testis, breast, esophagus, kidney, thyroid, lip, head and neck, and bone.

Cohort profile: the Saskatchewan Rural Health Study-adult component

OBJECTIVES

Less is known about the respiratory health of general farming and non-framing populations. A longitudinal Saskatchewan Rural Health Study (SRHS) was conducted to explore the association between individual and contextual factors with respiratory health outcomes in these populations. Hence, the objectives are to: (i) describe the updated methodology of longitudinal SRHS-an extension of baseline survey methodology published earlier; (ii) compare baseline characteristics and the prevalences of respiratory health outcomes between drops-outs and completers; and (iii) summarize key findings based on baseline survey data.

RESULTS

The SRHS was a prospective cohort study conducted in two phases: baseline survey in 2010 and a follow-up in 2014. Each survey consisted of two components, self-administered questionnaire and clinical assessments. At baseline, 8261 participants (≥ 18 years) (4624 households) and at follow-up, 4867 participants (2797 households) completed the questionnaires. Clinical assessments on lung functions and/or allergies were conducted among a sub-group of participants from both the surveys. To date, we published 15 peer-reviewed manuscripts and 40 abstracts in conference proceedings. Findings from the study will improve the knowledge of respiratory disease etiology and assist in the development and targeting of prevention programs for rural populations in Saskatchewan, Canada.

Association between RNASEL, MSR1, and ELAC2 single nucleotide polymorphisms and gene expression in prostate cancer risk

BACKGROUND

There is contradictory evidence of the effects that environmental factors-dietary habits (ingestion rates of red meat, soy products, fish, etc.) and work environment (exposure to metals, pesticides, several toxic products, etc.)-and KLK3, AR, RNASEL, MSR1, and ELAC2 expression patterns have on prostate cancer (PCa). In our study, we investigated the potential association between KLK3, AR, RNASEL, MSR1, and ELAC2 polymorphisms, expression patterns, exposure to environmental factors, and PCa in a Spanish cohort. Blood and fresh tissue samples were collected from 322 subjects with prostate-specific antigen (PSA)>4ng/ml to determine their genotypes (RNASEL, MSR1, and ELAC2) and assess messenger ribonucleic acid expression levels (by quantitative amplification testing).

MAIN FINDINGS

Among clinical parameters, a 63.6% of patients with CC variants in rs11545302 (ELAC2) had PSA>20ng/ml (P = 0.008), and rs486907 (RNASEL), with 52.8% of patients with CT variants with Gleason score>7. Regarding TNM stage, patients with GG variants, rs4792311 (ELAC2) generally had stage 1 tumors. Genetic expression analysis revealed RNASEL (P = 0.007) was underexpressed in PCa tissue, whereas KLK3 (P = 0.041) was overexpressed. As to environmental factors, the intake of dried fruits (P = 0.036) and practice of sports (P = 0.024) revealed an effect in PCa. Moreover, environmental factors were observed to affect gene expression patterns. Thus, RNASEL (P = 0.018) and ELAC2 (P = 0.023) were found to be underexpressed in patients who ate processed foods frequently; MSR1 (P = 0.024) and AR (P = 0.004) were underexpressed in patients who did not practice sports; and KLK3 (P = 0.039; P = 0.046) underexpressed in patients exposed to dust and toxic products.

CONCLUSIONS

This is the first study to analyze the correlation between RNASEL, MSR1, and ELAC2 genotypes and messenger ribonucleic acid expression in PCa. RNASEL and KLK3 show different expression patterns in normal vs. tumor tissue, which supports their reported relevance in human cancer. The results obtained confirm that RNASEL plays a crucial role in PCa. Environmental factors such as exercise, exposure to toxic agents, and intake of processed foods are associated with PCa.

Natural resource-based industries and prostate cancer risk in Northeastern Ontario: a case-control study

OBJECTIVE

Prostate cancer continues to be the most commonly diagnosed cancer in men, and there is limited knowledge on its preventable risk factors. A number of occupational exposures in natural resource-based industries are suspected to be related to prostate cancer risk. This study investigates associations between employment in these industries and prostate cancer.

METHODS

Data were from a population-based, case-control study previously conducted in Northeastern Ontario. Incident cases (N=760) aged 45-85 years and diagnosed with prostate cancer between 1995 and 1998 were identified from the Ontario Cancer Registry. Controls (N=1632) were recruited using telephone listings, and were frequency matched to cases by age. Lifetime occupational history was collected for all participants. Logistic regression was used to estimate ORs and their associated 95% CIs.

RESULTS

Elevated risks were observed for employment in forestry and logging industries (OR=1.87, 95% CI 1.32 to 2.73) and occupations (OR=1.71, 95% CI 1.24 to 2.35), and these risks increased with duration of employment for ≥10 years. Elevated risks were also found for employment in wood products industries (OR=1.45, 95% CI 1.07 to 1.97), and paper and allied products industries (OR=1.43, 95% CI 1.03 to 2.00), and when duration of employment was ≥10 years. There were also elevated risks in agriculture and mining-related work; however, these findings were not consistent across industry and occupation categories.

CONCLUSIONS

Prostate cancer risk may be associated with work in several natural resource industries, primarily in the forest industries. To further evaluate observed associations, studies should focus on natural resource-based exposures in larger populations with improved exposure assessment.