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control subjects, were investigated and their associations present studies are needed to make an exact estimation of
were assessed with prognostic factors. The present the results of current studies.
case control study was done to determine possible
relationships between AA, AG and GG polymorphisms References
of CTLA-4 gene and breast cancer-related factors. Results 1. Boring CC, Squires TS, Tong T, Montgomery S. Cancer
revealed that the frequency of AA and GG genotypes in statistic, 2004. CA Cancer J Clin 1994;44:7-26.
breast cancer patients is higher than in controls, while 2. Lippman ME, Lichter AS, Danforth DN Jr. Diagnosis and
AG genotype is more frequent in healthy controls. Management of Breast Cancer. Philadelphia: WB Saunders
These results confi rm the fi ndings of two other studies Co.; 1988.
in Iran and China, which found GG genotype is 3. Henderson IC, Canellos GP. Cancer of the breast: the past
[32]
[23]
decade (fi rst of two parts). N Engl J Med 1980;302:17-30.
more frequent in breast cancer patients. However, Erfani 4. Bakhtiari A, Haj-Ahmadi M. Five-year assessment of b reast
et al. did not fi nd any difference between their study cancer at Rajaee Hospital, Baboolsar (1991-1996). Iran J
[24]
groups in terms of AG genotype. Another study in China Obstets Gynecol Infertil 2006;9:47-52.
suggested that AG genotype is more prevalent in breast 5. Li F, Sturgis EM, Chen X, Zafereo ME, Wei Q, Li G.
[15]
cancer patients. Furthermore, Sun et al. reported Association of p53 codon 72 polymorphism with risk of
[33]
that T cells with AA genotype are less active than those second primary malignancy i n patients with squamous cell
with GG genotype, and AG is related to different cancer carcinoma of the head and neck. Cancer 2010;116:2350-9.
incidence in humans. 6. Wang G, Yu D, Tan W, Zhao D, Wu C, Lin D. Genetic
polymorp hism in chemokine CCL22 and susceptibility to
The results of our study did not fi nd any relation between Helicobacter pylori infection-related gastric carcinoma.
AA, AG and GG genotypes with respect to tumor stage, Cancer 2009;115:2430-7.
grade, receptors or lymph node involvement. These 7. Kristensen VN, Børresen-Dale AL. SNPs associated with
molecular subtypes of breast cancer: On the usefulness of
results are in agreement with results of Wang et al., stratifi ed Genome-wide Association Studies (GWAS) in
[16]
who found no signifi cant relationship between AG the identifi cation of novel susceptibility loci. Mol Oncol
genotype and tumor size and lymph node involvement. 2008;2:12-5.
Erfani et al. found a relationship between AA genotype 8. Kraft P, Haiman CA. GWAS identifi es a common breast cancer
[24]
and lower lymph node involvemen t and higher ER risk allele among BRCA1 carriers. Nat Genet 2010;42:819-20.
expression, but Ghaderi et al. found that AA genotype 9. Dranoff G. CTLA-4 blockade: unveiling immune regulation.
[23]
J Clin Oncol 2005;23:662-4.
is related to higher rates of lymph node involvement and 10. Hurwitz AA, Kwon ED, van Elsas A. Costimulatory wars: the
tumor size; these fi ndings are different from our fi ndings. tumor menace. Curr Opin Immunol 2000;12:589-96.
Bi et al. in his study reported that CTLA-4 expression 11. Chen L. Co-inhibitory molecules of the B7-CD28 family in the
[34]
is higher in stage 2 than stage 3 patients. There are also control of T-cell immunity. Nat Rev Immunol 2004;4:336-47.
some other studies, which revealed that CTLA-4 gene 12. Leach DR, Krummel MF, Allison JP. Enhancement
polymorphisms are related to higher stages and lymph of antitumor immunity by CTLA-4 blockade. Science
node metastasis, [6,32] which is not consistent with our 1996;271:1734-6.
study. According to age, in our study and also in the Bi 13. Hurwitz AA, Foster BA, Kwon ED, Truong T, Choi EM,
[34]
et al., there was no relationship between CTLA-4 gene Greenberg NM, Burg MB, Allison JP. Combination
immunotherapy of primary prostate cancer in a transgenic
polymorphisms and age. mouse model using CTLA-4 blockade. Cancer Res
2000;60:2444-8.
Li et al. found a relationship between all CTLA-4 gene
[32]
polymorphisms with estrogen and progesterone receptors. 14. Ligers A, Teleshova N, Masterman T, Huang WX, Hillert J.
CTLA-4 gene expression is infl uenced by promoter and exon
Also, Erfani et al. detected a relationship between AG 1 polymorphisms. Genes Immun 2001;2:145-52.
[24]
genotype and ER expression, which was not consistent 15. Sun T, Zhou Y, Yang M, Hu Z, Tan W, Han X, Shi Y, Yao J,
with our fi ndings. Guo Y, Yu D, Tian T, Zhou X, Shen H, Lin D. Functional
genetic variations in cytotoxic T-lymphocyte antigen 4
One of the limitations of our study is the failure to and susceptibility to multiple types of cancer. Cancer Res
take into account risk factors such as age at menarche, 2008;68:7025-34.
menopausal status, and environmental factors. It 16. Wang L, Li D, Fu Z, Li H, Jiang W, Li D. Association of
is imp ortant to investigate the interaction between CTLA-4 gene polymorphisms with sporadic breast cancer in
single-nucleotide polymorphisms and these factors on the Chinese Han population. BMC Cancer 2007;7:173.
risk of breast cancer in a larger sample size in further 17. Kouki T, Sawai Y, Gardine CA, Fisfalen ME, Alegre ML,
studies. DeGroot LJ. CTLA-4 gene polymorphism at position 49
in exon 1 reduces the inhibitory function of CTLA-4 and
Based on our study, there is a relationship between contributes to the pathogenesis of Graves’ disease. J Immunol
CTLA-4 gene 1661AG polymorphisms and incidence of 2000;165:6606-11.
breast cancer, but these polymorphisms are not effective 18. Mäurer M, Loserth S, Kolb-Mäurer A, Ponath A, Wiese S,
Kruse N, Rieckmann P. A polymorphism in the human
for prognosis. Considering the controversial reports on cytotoxic T-lymphocyte antigen 4 (CTLA4) gene (exon 1 +49)
this issue, more studies are needed with larger sample alters T-cell activation. Immunogenetics 2002;54:1-8.
size. Also, a critical review and possible meta-analysis of 19. Ueda H, Howson JM, Esposito L, Heward J, Snook H,
Journal of Cancer Metastasis and Treatment ¦ Volume 1 ¦ Issue 1 ¦ April 15, 2015 ¦ 19