AUTHOR=Naif Hassan M. , Al-Obaide Mohammed A. I. , Hassani Hayfa H. , Hamdan Abdualghani S. , Kalaf Zainab S. 

TITLE=Association of Cytochrome CYP1A1 Gene Polymorphisms and Tobacco Smoking With the Risk of Breast Cancer in Women From Iraq

JOURNAL=Frontiers in Public Health

VOLUME=6

YEAR=2018

URL=https://www.frontiersin.org/journals/public-health/articles/10.3389/fpubh.2018.00096

DOI=10.3389/fpubh.2018.00096

ISSN=2296-2565

ABSTRACT=<sec id="ST1"><title>Background</title><p><italic>CYP1A1</italic> gene polymorphisms and tobacco smoking are among several risk factors for various types of cancers, but their influence on breast cancer remains controversial. We analyzed the possible association of <italic>CYP1A1</italic> gene polymorphisms and tobacco smoking-related breast cancer in women from Iraq.</p></sec><sec id="ST2"><title>Materials and methods</title><p>In this case–control study, gene polymorphism of <italic>CYP1A1</italic> gene (<italic>CYP1A1m1</italic>, T6235C and <italic>CYP1A1m2</italic>, A4889G) of 199 histologically verified breast cancer patients’ and 160 cancer-free control women’s specimens were performed by using PCR-based restriction fragment length polymorphism.</p></sec><sec id="ST3"><title>Results</title><p>Three genotype frequencies (TT, TC, and CC) of <italic>CYP1A1m1T/C</italic> appeared in 16.1, 29.6, and 54.3% of women with breast cancer, respectively, compared with 41.2, 40, and 18.8% in the control group, respectively. <italic>CYP1A1m1</italic> CC genotype and C allele were significantly associated with increased risks for breast cancer in patients (54.3 and 69%, respectively) compared with controls (18.8 and 39%, respectively). While the three genotype frequencies (AA, AG, and GG) of <italic>CYP1A1m2A/G</italic> were detected in 20.1, 31.2, and 48.7% in patients compared with 46.3, 40.6, and 13.1% in controls, respectively. The frequency of GG genotypes and G allele was significantly higher in patients (48.7 and 64%, respectively) than in the controls (13.1 and 33%, respectively). Smoking women having either CC or GG genotypes showed a highly significant association with increased risk of breast cancer [odds ratio (OR) = 1.607, 95% confidence interval (CI) 0.91–1.64, <italic>p</italic> = 0.0001, and OR, 1.841, 95% CI, 0.88–1.67, <italic>p</italic> = 0.0001, respectively]. On the other hand, the T and A alleles of predominantly seen in healthy smoking women (83 and 85%, <italic>p</italic> = 0.0001, respectively).</p></sec><sec id="ST4"><title>Conclusion</title><p>These findings indicated that both C and G alleles of <italic>CYP1A1m1</italic> and <italic>m2</italic> were significantly associated with elevated risk of breast cancer in Iraqi women, while the T and A alleles were predominantly seen in healthy controls which may indicate their protective role. The C and G association with breast cancer incidence was more prevalent among tobacco smoking patients. These polymorphisms may be used as biomarkers of breast cancer in women from Iraq.</p></sec>