title: Epstein-Barr virus and breast cancer: epidemiological and molecular study on Egyptian and Iraqi women.
abstract: OBJECTIVE
  The role of Epstein-Barr virus (EBV) in breast carcinogenesis is still controversial. Unraveling this relationship is potentially important for better understanding of breast cancer etiology, early detection and possibly prevention of breast cancer. The aim of the current study is to unravel the association between EBV and primary invasive breast cancer (PIBC) in two different Arab populations (Egyptian and Iraqi women).
  
  
  METHODS
  The study was done on paraffin-embedded tissues of 40 Egyptian and 50 Iraqi patients with PIBC in addition to 20 normal breast tissues as controls for each group. Both controls and neoplastic tissues were assessed for the expression of EBV genes and proteins (EBNA-1, LMP-1, and EBER) as well as CD21 marker by immunohistochemistry (IHC), in situ hybridization (ISH) and PCR techniques.
  
  
  RESULTS
  Our gold standard for EBV reactivity in breast cancer cases was positivity of both EBNA1 by PCR and EBER by in situ hybridization. EBV was detected in 18/40 (45%) and 14/50 (28%) of Egyptian and Iraqi women; respectively where p=0.073, compared to 0/20 (0%) of their control groups (p<0.05). Regarding the association between EBV positivity and tumor grade, there was not any statistical significant difference between EBV presence and tumor grade in both populations where p=0.860 and p=0.976 and the calculated rank biserial correlation coefficient was 0.114 and 0.269 for Egyptian and Iraqi women respectively.
  
  
  CONCLUSIONS
  Our findings show that EBV might act as a promoter for the development of PIBC and it might contribute to increased tumor aggressiveness in Egyptian and Iraqi patients.
authors.affiliation: Virology and Immunology Unit, Cancer Biology Department, National Cancer Institute, Cairo University, Cairo 11976, Egypt. ncizekri@yahoo.com
authors.forename: Abdel-Rahman N
authors.initials: AR
authors.lastname: Zekri
authors.forename: Abeer A
authors.initials: AA
authors.lastname: Bahnassy
authors.forename: Waleed S
authors.initials: WS
authors.lastname: Mohamed
authors.forename: Fatma A
authors.initials: FA
authors.lastname: El-Kassem
authors.forename: Saja J
authors.initials: SJ
authors.lastname: El-Khalidi
authors.forename: Mohamed M
authors.initials: MM
authors.lastname: Hafez
authors.forename: Zeinab K
authors.initials: ZK
authors.lastname: Hassan
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism; D001943:Breast Neoplasms / Q000453:epidemiology / Q000378:metabolism / Q000821:virology*; D018270:Carcinoma, Ductal, Breast / Q000453:epidemiology / Q000378:metabolism / Q000821:virology*; D018275:Carcinoma, Lobular / Q000453:epidemiology / Q000378:metabolism / Q000821:virology*; D004534:Egypt / Q000453:epidemiology; D020031:Epstein-Barr Virus Infections / Q000150:complications* / Q000453:epidemiology / Q000378:metabolism; D005260:Female; D015870:Gene Expression; D004854:Herpesvirus 4, Human / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007493:Iraq / Q000453:epidemiology; D008875:Middle Aged; D017720:Molecular Epidemiology; D017464:Receptors, Complement 3d / Q000378:metabolism; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; D017464:Receptors, Complement 3d; D014764:Viral Proteins