Breast cancer is the most common cancer type and the leading cause of cancer-related deaths in women, worldwide. Besides, it accounts for 23% of cancers and 400000 deaths, annually [1]. The prevalence of breast cancer is approximately one-third of all cancers in women; it is the second most common cancer after lung cancer and the most frequent cause of cancer-induced death among women. Fibroblast Growth Factor Receptor 2 (FGFR2) is a tyrosine kinase receptor that plays an essential role in cell growth and differentiation. The structure of these receptors has a second binding to the extracellular ligand, a second crossing the membrane, and a second intracellular tyrosine kinase. According to GWA studies, the FGFR2 gene was suggested as a gene susceptible to breast cancer [8]. Genetic diversity in this receptor is a new risk factor for breast cancer. This study aimed to evaluate the association of rs2981582C/T single nucleotide polymorphism with breast cancer in females.

In the present case-control study, the required blood samples were obtained from 80 patients referring to Ayatollah Khansari Hospital in Arak City, Iran as well as 80 healthy individuals (controls). Moreover, written informed consent forms were collected from the explored individuals. Accordingly, 5cc of peripheral blood was collected in EDTA tubes; the samples remained at -20°C until DNA extraction. After completing the questionnaire, data, such as age, marital status, occupational status, diet, the number of children, the age of first menstruation, menopausal status, etc. were collected. All study patients were female with a mean age of 50 years. Iriazol (RENA biotechnologists) kit was used to extract DNA in this study. Extraction was performed according to the protocol of the kit. The quality, as well as the concentration of DNA extracted by spectrophotometer (V-US gene), the P electrophoresis of the samples, were performed on 1% agarose gel. The research samples were genotyped by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR - RFLP) and AciI restriction enzyme at rs2981582 C/T locus. All statistical analyzes were performed using SPSS. To evaluate the association between disease and genotypes, Odds Ratio (OR) and Chi-squared test at a 95% Confidence Interval (CI) were used at P<0.05.

The obtained data suggested a confidence level of P=0.000; there was a significant relationship between rs2981582 and breast cancer. It was also observed that the T allele of this polymorphism was associated with the risk of breast cancer (P=0.0003; 95%CI: 2.925 or = 1.864-433). The frequency of the C allele in the patient and control groups was equal to 44.37% and 65.62%, respectively. Besides, the frequency of the T allele in the patient and control groups was measured as 55.62% and 34.37%, respectively. According to the relevant results, there was a significant relationship between TT genotype and disease (P=0.001; 95%CI: 566.3 or =1.589-8005). Additionally, the greater frequency of CC genotype in the control group of this genotype probably presents a protective effect on the disease. Furthermore, the risk of breast cancer in patients carrying CT + TT genotypes was about 3 times higher than that in the controls (P=0.0003; 95%CI: 545.1 or 807.921-7). The mean age of the examined patients and controls was 50 and 40 years, in sequence. There was a significant relationship between age and breast cancer (P=0.000). The familial history of breast cancer signified a significant relationship between this characteristic and the disease (P=0.007). However, marital status or the consumption of contraceptives indicated no significant relationship with breast cancer between the study groups (Tables 1 & 2).

Genetic factors and the lifestyle of individuals impact breast cancer risk [13]. The FGFR2 gene, which belongs to the fibroblast growth factor receptor family is involved in mammary gland development; it has been identified as an important gene candidate in breast cancer [14]. This receptor is involved in several processes, including cell proliferation, angiogenesis, and migration [15]. The genetic variants of this gene are a risk factor for breast cancer [16]. The present study examined the effect of rs2981582 polymorphism in 80 patients and the same number of controls on breast cancer risk. Accordingly, the relevant data indicated a significant relationship between this polymorphism and generating the disease (P=0.000). T allele of this single polymorphism nucleotides is more frequently present in patients than healthy individuals. Besides, the heterozygous minor (TT) genotype was significantly associated with the disease. The C allele presents a protective effect on the disease. Furthermore, individuals with at least one T allele in their genotype (CT + TT) are almost 3 times more prone to develop breast cancer (P=0.807 or =0.0003). The achieved results were consistent with those of numerous studies. For example, Fangmeng, in a similar study in southern China revealed that the heterozygous minor (TT) genotype of this polymorphism was associated with developing breast cancer. Moreover, Zamora et al. explored a population of Mexican women; they reported a significant association between the T allele of this polymorphism and the risk of breast cancer. At present, numerous attempts focus on targeting genetic changes that cause breast cancer. Moreover, the FGFR2 gene involved in various human malignancies, including breast cancer, is considered a probable candidate. Due to the significance of rs2981582 single nucleotide polymorphism to breast cancer risk, this single nucleotide polymorphism can be used as a biomarker to predict breast cancer.

This study was approved by the Ethics Committee of the Arak University (Code: IR.ARAKMU.REC.1395.28).

The paper was extracted from the MSc. thesis of the second author at the Department of Biology, Faculty of Sciences, University of Arak. 

All authors met the writing standards based on the recommendations of the International Committee of Medical Journal Publishers (ICMJE).

The authors declared no conflict of interest.

The authors express their gratitude to the medical staff of Shahid Khansari Hospital in Arak and the esteemed staff of the University New Biology Research Laboratory.
 

Reference

1. Liu CL, Hu XP, Guo WD, Yang L, Dang J, Jiao HY. Case-control study on the fibroblast growth factor receptor 2 gene polymorphisms associated with breast cancer in Chinese Han women. J Breast Cancer. 2013; 16(4):366-71. [DOI:10.4048/jbc.2013.16.4.366] [PMID] [PMCID]
2. Asgarian F, Mirzaei M, Asgarian S, Jazayeri M. [Epidemiologic study of breast cancer and age distribution of patients in a ten-year interval (Persian)]. Iran J Breast Dis. 2016; 9(1):31-6. http://ijbd.ir/article-1-507-fa.html
3. Jazayeri SB, Saadat S, Ramezani R, Kaviani A. Incidence of primary breast cancer in Iran: Ten-year national cancer registry data report. Cancer Epidemiol. 2015; 39(4):519-27. [DOI:10.1016/j.canep.2015.04.016] [PMID]
4. Mohaghegh F, Hamta A. [The study of cancer incidence and cancer registration in Markazi province between 2001-2006 and comparison with national statistics, Iran (Persian)]. Arak Med Univ J. 2008; 11(2):84-93. https://www.sid.ir/en/journal/ViewPaper.aspx?ID=118837
5. Pecorino L. Molecular biology of cancer: Mechanisms, targets, and therapeutics. 3^th ed. United Kingdom: Oxford university press; 2012. https://www.amazon.com/Molecular-Biology-Cancer-Mechanisms-Therapeutics/dp/019957717X
6. Motovali Bashi M, Gholampur M. [The association of A/G Polymorphism in Intronic region of FGFR2 gene and breast cancer (Persian)]. J Isfahan Med Sch . 2014; 32(279). https://www.sid.ir/fA/Journal/ViewPaper.aspx?id=221808
7. Shah R, Rosso K, Nathanson SD. Pathogenesis, prevention, diagnosis and treatment of breast cancer. World J Clin Oncol. 2014; 5(3):283-98. [DOI:10.5306/wjco.v5.i3.283] [PMID] [PMCID]
8. Schultz PN, Klein MJ, Beck ML, Stava C, Sellin RV. Breast cancer: relationship between menopausal symptoms, physiologic health effects of cancer treatment and physical constraints on quality of life in long-term survivors. J Clin Nurs. 2005; 14(2):204-11. [DOI:10.1111/j.1365-2702.2004.01030.x] [PMID]
9. Tenhagen M, van Diest PJ, Ivanova IA, van der Wall E, van der Groep P. Fibroblast growth factor receptors in breast cancer: Expression, downstream effects, and possible drug targets. Endocr Relat Cancer. 2012; 19(4):R115-29. [DOI:10.1530/ERC-12-0060] [PMID]
10. Martin AJ, Grant A, Ashfield AM, Palmer CN, Baker L, Quinlan PR, et al. FGFR2 protein expression in breast cancer: Nuclear localisation and correlation with patient genotype. BMC Res Notes. 2011; 4:72. [DOI:10.1186/1756-0500-4-72] [PMID] [PMCID]
11. Turner N, Grose R. Fibroblast growth factor signalling: from development to cancer. Nat Rev Cancer. 2010; 10(2):116-29. [DOI:10.1038/nrc2780] [PMID]
12. Sun C, Olopade OI, Di Rienzo A. rs2981582 is associated with FGFR2 expression in normal breast. Cancer Genet Cytogenet. 2010; 197(2):193-4. [DOI:10.1016/j.cancergencyto.2009.11.006] [PMID] [PMCID]
13. Boyarskikh UA, Zarubina NA, Biltueva JA, Sinkina TV, Voronina EN, Lazarev AF, eta al. Association of FGFR2 gene polymorphisms with the risk of breast cancer in population of West Siberia. Eur J Hum Genet. 2009; 17(12):1688-91. [DOI:10.1038/ejhg.2009.98] [PMID] [PMCID]
14. Saadatian Z, Gharesouran J, Ghojazadeh M, Ghohari-Lasaki S, Tarkesh-Esfahani N, Ardebili SM. Association of rs1219648 in FGFR2and rs1042522 in TP53with premenopausal breast cancer in an Iranian Azeri population. Asian Pac J Cancer Prev. 2014; 15(18):7955-8. [DOI:10.7314/APJCP.2014.15.18.7955] [PMID]
15. Wolff MS, Weston A. Breast cancer risk and environmental exposures. Environ Health Perspect. 1997; 105(S 4):891-6. [DOI:10.1289/ehp.97105s4891] [PMID] [PMCID]
16. Taskin II, Tekin MA, Pektanc G, Munzuroglu O, Kandemir SI. Polymorphism in the second intron of the FGFR2 gene rs1219648 associated with the early-onset breast cancer in Turkish population. Int J Clin Exp Med. 2017; 10(7):10989-94. http://www.ijcem.com/files/ijcem0045279.pdf
17. Fu F, Wang C, Huang M, Song C, Lin S, Huang H. Polymorphisms in second intron of the FGFR2 gene are associated with the risk of early-onset breast cancer in Chinese Han women. Tohoku J Exp Med. 2012; 226(3):221-9. [DOI:10.1620/tjem.226.221] [PMID]
18. Siddiqui S, Chattopadhyay S, Akhtar MS, Najm MZ, Deo SV, Shukla NK, et al. A study on genetic variants of Fibroblast growth factor receptor 2 (FGFR2) and the risk of breast cancer from North India. PLoS One. 2014; 9(10):e110426. [DOI:10.1371/journal.pone.0110426] [PMID] [PMCID]
19. Murillo-Zamora E, Moreno-Macías H, Ziv E, Romieu I, Lazcano-Ponce E, Ángeles-Llerenas A, et al. Association between rs2981582 polymorphism in the FGFR2 gene and the risk of breast cancer in Mexican women. Arch Med Res. 2013; 44(6):459-66. [DOI:10.1016/j.arcmed.2013.08.006] [PMID] [PMCID]
20. Meyer KB, Maia AT, O'Reilly M, Teschendorff AE, Chin SF, Caldas C, et al. Allele-specific up-regulation of FGFR2 increases susceptibility to breast cancer. PLoS Biol. 2008; 6(5):e108. [DOI:10.1371/journal.pbio.0060108] [PMID] [PMCID]
21. Özgöz A, Şamlı H, Öztürk KH, Orhan B, Içduygu FM, Aktepe F, et al. An investigation of the effects of FGFR2 and B7-H4 polymorphisms in breast cancer. J Cancer Res Ther. 2013; 9(3):370-5. [DOI:10.4103/0973-1482.114434] [PMID]
22. Pan Z, Bao Y, Zheng X, Cao W, Cheng W, Xu X. Association of polymorphisms in intron 2 of FGFR2 and breast cancer risk in Chinese women. Cytol Genet . 2016; 50:312-7. [DOI:10.3103/S009545271605008X]