Document Type : Original Article

Authors

Department of Biochemistry and Microbiology, Faculty of Pharmacy, Damascus University, Damascus, Syria

Abstract

Background: The main goal of the present study was to investigate BRCA1 and BRCA2 mutations in a number of Syrian familial breast cancer cases. We included 50 early onset invasive breast cancer patients from different Syrian families (48 females and 2 males) and 20 healthy women (control group) in the study. All participants were matched for age (28 to 49 years). There were 64% of breast cancer patients who had a significant family history of breast cancer.Methods: DNA was isolated from blood samples and we performed polymerase chain reaction on the isolated DNA to amplify specific target regions (hotspots): exon 2 of the BRCA1 gene and exon 11 of the BRCA2 gene. Polymerase chain reaction products were then sequenced to investigate possible genetic variations that could be present in the examined regions.Results: The sequenced polymerase chain reaction products revealed 3 point mutations that included two deletions and one substitution. An exon 2 mutation was found in 2% of the breast cancer patients. Mutations of exon 11 were each found in 4% of the patient group. We detected no founder mutations. The detected exon 2 mutation was previously mentioned by other researchers and classified as a harmful mutation.Conclusion: To the best of our knowledge, the detected mutations in exon 11 of the BRCA2 gene were not previously identified. A significant association existed between those mutations and the triple negative subtype of breast cancer in Syrian familial breast cancer patients.

 
1.Bensam M, Hafez E, Awad D, El-Saadani M, Balbaa M. Detection of new point mutations of BRCA1 and BRCA2 in breast cancer patients. Biochem Genet. 2013;52(1-2):15-28.
 
2.      ParkinDM, BrayF, FerlayJ, PisaniP. Global cancer statistics, 2002. CA Cancer J Clin. 2005;55(2):74-108.
 
3.      Rapid Assessment of Cancer Management Care in Syria. A report by WHO Syria Office in coordination with WHO Headquarters, WHO Regional Office and the National Committee for Cancer Care. Syria: Ministry of Health; 2016. Available from: http://www.moh.gov.sy/Default.aspx?tabid=565&language=ar-YE. [Accessed date: July 2017].
 
4.      Barlow-Stewart, K; Emery, J; Metcalfe, S; Dunlop, K; Kirk, J; Tucker, K. Genetics in family medicine: The Australian Handbook for General Practitioners. In: Barlow-Stewart, K; Emery, J; Metcalfe, S, editors. Australia: The Australian Government Agency Biotechnology, Australia; 2007. Chapter 4, Cancer in the family.p. 1-23.
 
5.      Branković-Magić M, Dobricić J, Krivokuća A. Genetics of breast cancer: contribution of BRCA1/2 genes alterations to hereditary predisposition. Vojnosanit Pregl. 2012;69(8):700-6.
 
6.      Lin PH, Kuo WH, Huang AC, Lu YS, Lin CH, Kuo SH, et al. Multiple gene sequencing for risk assessment in patients with early-onset or familial breast cancer.Oncotarget. 2016;7(7):8310-20.
 
7.      Walsh T, King MC. Ten genes for inherited breast cancer. Cancer Cell. 2007;11(2):103-5.
 
8.      McClellan J, King MC. Genetic heterogeneity in human disease. Cell. 2010;141(2):210-7.
 
9.      Metcalfe KA, Lubinski J, Gronwald J, Huzarski T, McCuaig J, Lynch HT, et al. The risk of breast cancer in BRCA1 and BRCA2 mutation carriers without a first-degree relative with breast cancer. Clin Genet. 2017; [Epub ahead of print].
 
10.  Pinsky LE, Culver JB, Hull J, Levy-Lahad E, Daly M, Burke W. Why should primary care physicians know about breast cancer genetics? West J Med. 2001;175(3):168-73.
 
11.  Karami F, Mehdipour P. A comprehensive focus on global spectrum of BRCA1 and BRCA2 mutations in breast cancer. Biomed Res Int. 2013;2013:928562.
 
12.  Narod SA, Foulkes WD. BRCA1 and BRCA2: 1994 and beyond. Nat Rev Cancer. 2004;4(9):665-76.
 
13.  Lindor NM, McMaster ML, Lindor CJ, Greene MH; National Cancer Institute, Division of Cancer Prevention, et al. Concise handbook of familial cancer susceptibility syndromes - second edition.J Natl Cancer Inst Monogr.2008;(38):1-93.
 
14.  Ferla R, Calò V, Cascio S, Rinaldi G, Badalamenti G, Carreca I, et al. Founder mutations in BRCA1 and BRCA2 genes. Ann Oncol. 2007;18 Suppl 6:vi93-8.
 
15.  Simard J, Tonin P, Durocher F, Morgan K, Rommens J, Gingras S, et al. Common origins of BRCA1 mutations in Canadian breast and ovarian cancer families. Nat Genet. 1994;8(4):392-8.
 
16.  Oddoux C, Struewing JP, Clayton CM, Neuhausen S, Brody LC, Kaback M, et al. The carrier frequency of the BRCA2 6174delT mutation among Ashkenazi Jewish individuals is approximately 1%. Nat Genet. 1996;14(2):188-90.
 
17.  Brankovic-Magic M, Dobricic J, Jankovic R, Konstantopoulou I, Yannoukakos D, Radulovic S. Identifying and testing for hereditary susceptibility to breast/ovarian cancer in Serbia: Where are we now? Arch Oncol. 2006;14(3-4):131-5.
 
18.  Martin AM, Weber BL. Genetic and hormonal risk factors in breast cancer. J Natl Cancer Inst. 2000;92(14):1126-35.
 
19.  Onitilo AA, Engel JM, Greenlee RT, Mukesh BN. Breast cancer subtypes based on ER/PR and Her2 expression: comparison of clinicopathologic features and survival. Clin Med Res. 2009;7(1-2):4-13.
 
20.  Anagha PP, Sen S. The efficacy of bisphosphonates in preventing aromatase inhibitor induced bone loss for postmenopausal women with early breast cancer: a systematic review and meta-analysis. J Oncol. 2014;2014:625060.
 
21.  Foulkes WD, Smith IE, Reis-Filho JS. Triple-negative breast cancer. N Engl J Med. 2010;363(20):1938-48.
 
22.   Liedtke C, Mazouni C, Hess KR, André F, Tordai A, Mejia JA,  et al. Response to neoadjuvant therapy and long-term survival in patients with triple-negative breast cancer. J Clin Oncol. 2008;26(8):1275-81.  
 
23.   Couch FJ, Hart SN, Sharma P, Toland AE, Wang X, Miron P, et al. Inherited mutations in 17 breast cancer susceptibility genes among a large triple-negative breast cancer cohort unselected for family history of breast cancer. J Clin Oncol. 2015;33(4):304-11.
 
24.  Lang GT, Shi JX, Hu X, Zhang CH, Shan L, Song CG, et al. The spectrum of BRCA mutations and characteristics of BRCA-associated breast cancers in China: Screening of 2,991 patients and 1,043 controls by next-generation sequencing. Int J Cancer. 2017;141(1):129-142.
 
25.   Dobricić J, Branković-Magić M, Filipović S, Radulović S. Novel BRCA1/2 mutations in Serbian breast and breast-ovarian cancer patients with hereditary predisposition. Cancer Genet Cytogenet. 2010;202(1):27-32.
 
26.  Sweet K, Senter L, Pilarski R, Wei L, Toland AE. Characterization of BRCA1 ring finger variants of uncertain significance. Breast Cancer Res Treat. 2010;119(3):737-43.
 
27.  Tavtigian SV, Byrnes GB, Goldgar DE, Thomas A. Classification of rare missense substitutions, using risk surfaces, with genetic- and molecular-epidemiology applications. Hum Mutat. 2008;29(11):1342-54.
 

28.  Yeh J, Chun J, Schwartz S, Wang A, Kern E, Guth AA, et al. Clinical characteristics in patients with triple negative breast cancer. Int J Breast Cancer. 2017;2017:1796145.

 
29.  Luporsi E, Bronner M, Lesur A, Saint-Dizier D, Sokolowska J, Mansuy L, et al. Characteristics of the BRCA mutation profile of a population of patients with triple negative breast cancer. Cancer Res. 2013;73(24):2-12.
30. de Juan Jiménez I, García Casado Z, Palanca Suela S, Esteban Cardeñosa E, López Guerrero JA, Segura Huerta Á, et al. Novel and recurrent BRCA1/BRCA2 mutations in early onset and familial breast and ovarian cancer detected in the Program of Genetic Counseling in Cancer of Valencian Community (eastern Spain). Relationship of family phenotypes with mutation prevalence. Fam Cancer. 2013;12(4):767-77.
1.Bensam M, Hafez E, Awad D, El-Saadani M, Balbaa M. Detection of new point mutations of BRCA1 and BRCA2 in breast cancer patients. Biochem Genet. 2013;52(1-2):15-28.
2.      ParkinDM, BrayF, FerlayJ, PisaniP. Global cancer statistics, 2002. CA Cancer J Clin. 2005;55(2):74-108.
3.      Rapid Assessment of Cancer Management Care in Syria. A report by WHO Syria Office in coordination with WHO Headquarters, WHO Regional Office and the National Committee for Cancer Care. Syria: Ministry of Health; 2016. Available from: http://www.moh.gov.sy/Default.aspx?tabid=565&language=ar-YE. [Accessed date: July 2017].
4.      Barlow-Stewart, K; Emery, J; Metcalfe, S; Dunlop, K; Kirk, J; Tucker, K. Genetics in family medicine: The Australian Handbook for General Practitioners. In: Barlow-Stewart, K; Emery, J; Metcalfe, S, editors. Australia: The Australian Government Agency Biotechnology, Australia; 2007. Chapter 4, Cancer in the family.p. 1-23.
5.      Branković-Magić M, Dobricić J, Krivokuća A. Genetics of breast cancer: contribution of BRCA1/2 genes alterations to hereditary predisposition. Vojnosanit Pregl. 2012;69(8):700-6.
6.      Lin PH, Kuo WH, Huang AC, Lu YS, Lin CH, Kuo SH, et al. Multiple gene sequencing for risk assessment in patients with early-onset or familial breast cancer.Oncotarget. 2016;7(7):8310-20.
7.      Walsh T, King MC. Ten genes for inherited breast cancer. Cancer Cell. 2007;11(2):103-5.
8.      McClellan J, King MC. Genetic heterogeneity in human disease. Cell. 2010;141(2):210-7.
9.      Metcalfe KA, Lubinski J, Gronwald J, Huzarski T, McCuaig J, Lynch HT, et al. The risk of breast cancer in BRCA1 and BRCA2 mutation carriers without a first-degree relative with breast cancer. Clin Genet. 2017; [Epub ahead of print].
10.  Pinsky LE, Culver JB, Hull J, Levy-Lahad E, Daly M, Burke W. Why should primary care physicians know about breast cancer genetics? West J Med. 2001;175(3):168-73.
11.  Karami F, Mehdipour P. A comprehensive focus on global spectrum of BRCA1 and BRCA2 mutations in breast cancer. Biomed Res Int. 2013;2013:928562.
12.  Narod SA, Foulkes WD. BRCA1 and BRCA2: 1994 and beyond. Nat Rev Cancer. 2004;4(9):665-76.
13.  Lindor NM, McMaster ML, Lindor CJ, Greene MH; National Cancer Institute, Division of Cancer Prevention, et al. Concise handbook of familial cancer susceptibility syndromes - second edition.J Natl Cancer Inst Monogr.2008;(38):1-93.
14.  Ferla R, Calò V, Cascio S, Rinaldi G, Badalamenti G, Carreca I, et al. Founder mutations in BRCA1 and BRCA2 genes. Ann Oncol. 2007;18 Suppl 6:vi93-8.
15.  Simard J, Tonin P, Durocher F, Morgan K, Rommens J, Gingras S, et al. Common origins of BRCA1 mutations in Canadian breast and ovarian cancer families. Nat Genet. 1994;8(4):392-8.
16.  Oddoux C, Struewing JP, Clayton CM, Neuhausen S, Brody LC, Kaback M, et al. The carrier frequency of the BRCA2 6174delT mutation among Ashkenazi Jewish individuals is approximately 1%. Nat Genet. 1996;14(2):188-90.
17.  Brankovic-Magic M, Dobricic J, Jankovic R, Konstantopoulou I, Yannoukakos D, Radulovic S. Identifying and testing for hereditary susceptibility to breast/ovarian cancer in Serbia: Where are we now? Arch Oncol. 2006;14(3-4):131-5.
18.  Martin AM, Weber BL. Genetic and hormonal risk factors in breast cancer. J Natl Cancer Inst. 2000;92(14):1126-35.
19.  Onitilo AA, Engel JM, Greenlee RT, Mukesh BN. Breast cancer subtypes based on ER/PR and Her2 expression: comparison of clinicopathologic features and survival. Clin Med Res. 2009;7(1-2):4-13.
20.  Anagha PP, Sen S. The efficacy of bisphosphonates in preventing aromatase inhibitor induced bone loss for postmenopausal women with early breast cancer: a systematic review and meta-analysis. J Oncol. 2014;2014:625060.
21.  Foulkes WD, Smith IE, Reis-Filho JS. Triple-negative breast cancer. N Engl J Med. 2010;363(20):1938-48.
22.   Liedtke C, Mazouni C, Hess KR, André F, Tordai A, Mejia JA,  et al. Response to neoadjuvant therapy and long-term survival in patients with triple-negative breast cancer. J Clin Oncol. 2008;26(8):1275-81.  
23.   Couch FJ, Hart SN, Sharma P, Toland AE, Wang X, Miron P, et al. Inherited mutations in 17 breast cancer susceptibility genes among a large triple-negative breast cancer cohort unselected for family history of breast cancer. J Clin Oncol. 2015;33(4):304-11.
24.  Lang GT, Shi JX, Hu X, Zhang CH, Shan L, Song CG, et al. The spectrum of BRCA mutations and characteristics of BRCA-associated breast cancers in China: Screening of 2,991 patients and 1,043 controls by next-generation sequencing. Int J Cancer. 2017;141(1):129-142.
25.   Dobricić J, Branković-Magić M, Filipović S, Radulović S. Novel BRCA1/2 mutations in Serbian breast and breast-ovarian cancer patients with hereditary predisposition. Cancer Genet Cytogenet. 2010;202(1):27-32.
26.  Sweet K, Senter L, Pilarski R, Wei L, Toland AE. Characterization of BRCA1 ring finger variants of uncertain significance. Breast Cancer Res Treat. 2010;119(3):737-43.
27.  Tavtigian SV, Byrnes GB, Goldgar DE, Thomas A. Classification of rare missense substitutions, using risk surfaces, with genetic- and molecular-epidemiology applications. Hum Mutat. 2008;29(11):1342-54.

28.  Yeh J, Chun J, Schwartz S, Wang A, Kern E, Guth AA, et al. Clinical characteristics in patients with triple negative breast cancer. Int J Breast Cancer. 2017;2017:1796145.

29.  Luporsi E, Bronner M, Lesur A, Saint-Dizier D, Sokolowska J, Mansuy L, et al. Characteristics of the BRCA mutation profile of a population of patients with triple negative breast cancer. Cancer Res. 2013;73(24):2-12.
30.   de Juan Jiménez I, García Casado Z, Palanca Suela S, Esteban Cardeñosa E, López Guerrero JA, Segura Huerta Á, et al. Novel and recurrent BRCA1/BRCA2 mutations in early onset and familial breast and ovarian cancer detected in the Program of Genetic Counseling in Cancer of Valencian Community (eastern Spain). Relationship of family phenotypes with mutation prevalence. Fam Cancer. 2013;12(4):767-77.