• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1355-1360
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• 2012

Background: The cell cycle checkpoint kinase 2 (CHEK2) gene I157T variant may be associated with an increased risk of breast cancer, but it is unclear whether the evidence is sufficient to recommend testing for the mutation in clinical practice. Materials and Methods: We systematically searched PubMed, Embase, Elsevier and Springer for relevant articles published before Nov 2011. Summary odds ratio (OR) and 95% confidence interval (95% CI) incidence rates were calculated using a random-effects model with STATA (version 10.0) software. Results: A total of fifteen case-control studies, including 19,621 cases and 27,001 controls based on the search criteria, were included for analysis. A significant association was found between carrying the CHEK2 I157T variant and increased risk of unselected breast cancer (OR = 1.48, 95% CI = 1.31-1.66, P < 0.0001), familial breast cancer (OR = 1.48, 95% CI = 1.16-1.89, P < 0.0001), and early-onset breast cancer (OR = 1.47, 95% CI = 1.29-1.66, P < 0.0001). We found an even stronger significant association between the CHEK2 I157T C variant and increased risk of lobular type breast tumors (OR = 4.17, 95% CI = 2.89-6.03, P < 0.0001). Conclusion: Our research indicates that the CHEK2 I157T variant may be another important genetic mutation which increases risk of breast cancer, especially the lobular type.

• BMB Reports
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• v.40 no.1
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• pp.15-21
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• 2007

Breast cancer is the most common malignancy among women, and mutations in the BRCA1 gene produce increased susceptibility to these malignancies in certain families. In this study, the forward 1-13 exons of breast cancer associated gene BRCA1 were cloned from breast cancer cell line ZR-75-30 by RT-PCR method. Sequence analysis showed that nine BRCA1 splice forms were isolated and characterized, compared with wild-type BRCA1 gene, five splice forms of which were novel. These splice isoforms were produced from the molecular mechanism of 5' and 3' alternative splicing. All these splice forms deleting exon 11b and the locations of alternative splicing were focused on two parts:one was exons 2 and 3, and the other was exons 9 and 10. These splice forms accorded with GT-AG rule. Most these BRCA1 splice variants still kept the original reading frame. Western blot analysis indicated that some BRCA1 splice variants were expressed in ZR-75-30 cell line at the protein level. In addition, we confirmed the presence of these new transcripts of BRCA1 gene in MDA-MB-435S, K562, Hela, HLA, HIC, H9, Jurkat and human fetus samples by RT-PCR analysis. These results suggested that breast cancer associated gene BRCA1 may have unexpectedly a large number of splice variants. We hypothesized that alternative splicing of BRCA1 possibly plays a major role in the tumorigenesis of breast and/or ovarian cancer. Thus, the identification of cancer-specific splice forms will provide a novel source for the discovery of diagnostic or prognostic biomarkers and tumor antigens suitable as targets for therapeutic intervention.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2675-2679
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• 2012

Introduction: Annually a considerable number of people die because of breast cancer, a common disease among women also in Iran. Identifying risk factors and susceptible people can lead to prevention or at least early diagnosis. Among susceptibility risks, 5-10% of patients have a family history predisposing factor which can influence the risk of incidence among the family. Having a registry program can be a more practical way to screen high risk families for preventive planning. Method: Based on inclusion criteria, a questionnaire was prepared and after a pilot study on a small number of patients, actual data were collected on 400 patients and processed in SPSS 16.0. Results: Totally, 28.2%of the patients were younger than 40 years old and 36.8% had the included criteria for familial breast cancer (FBC). 102 patient's samples could be compared for receptor presentation. Similar to other studies, the number of triple negative breast cancers increased as the age decreased. Conclusion: The high percentage of patients with FBC among 400 cases in this study demonstrates that in order to design an infrastructural diagnostic protocol and screening of patients with FBC, a precise survey related to frequency and founder mutations of FBC is needed nationwide.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.22
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• pp.9643-9647
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• 2014

Background: Several studies have been performed to investigate the association of the HER2 Ile655Val polymorphism and breast cancer risk. However, the results were inconsistent. To understand the precise relationship, a meta-analysis was here conducted. Materials and Methods: A search of PubMed conducted to investigate links between the HER2 Ile655Val polymorphism and breast cancer, identified a total of 32 studies, of which 29, including 14,926 cases and 15,768 controls, with odds ratios (ORs) with 95% confidence intervals were used to assess any association. Results: In the overall analysis, the HER2 Ile655Val polymorphism was associated with breast cancer in an additive genetic model (OR=1.136, 95% CI 1.043-1.239, p=0.004) and in a dominant genetic (OR=1.118, 95% CI 1.020-1.227, p=0.018), while no association was found in a recessive genetic model. On subgroup analysis, an association with breast cancer was noted in the additive genetic model (OR=1.111, 95% CI: 1.004-1.230, p=0.042) for the Caucasian subgroup. No significant associations were observed in Asians and Africans in any of the genetic models. Conclusions: In summary, our meta-analysis findings suggest that the HER2 Ile655Val polymorphism is marginally associated with breast cancer susceptibility in worldwide populations with additive and dominant models, but not a recessive model.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.23
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• pp.10107-10114
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• 2015

MicroRNA-27a is highly expressed in cancers and has been identified as an oncogenic microRNA. A genetic variant in pre-miR-27a (rs895819) with a transition of A to G has been demonstrated to be associated with cancer risk; however, the results of these studies remain conflicting rather than conclusive. Therefore, we performed a meta-analysis to derive a more precise estimation. Through searching PubMed or other databases up to March 2014 using the following MeSH terms and keywords, "miR-27a", "polymorphism" and "cancer", seventeen case-control studies were identified in this meta-analysis, including 7,813 cases and 9,602. Crude odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were calculated to investigate the association strength between rs895819 and the susceptibility of cancer. The results of the overall meta-analysis did not suggest any association between rs895819 polymorphism and cancer susceptibility, and this remained in Asians as a subgroup. In Caucasians, however, the rs895819 was associated with a reduced cancer risk in heterozygous (OR, 0.83; 95%CI, 0.75-0.93) and dominant models (OR, 0.84; 95%CI, 0.76-0.93), and the [G] allele of rs895819 showed a protective effect (OR, 0.90, 95%CI, 0.84-0.97). Further studies showed a significant association between the [G] allele of rs895819 and decreased risk of breast cancer (0.91; 95%CI, 0.85-0.98), and stratified analyses indicated a protective effect of the [G] allele in Caucasians (OR, 0.89; 95%CI, 0.82-0.98), younger breast cancer cases (OR, 0.87; 95%CI, 0.79-0.96), and in the group of unilateral breast cancer patients (OR, 0.90; 95%CI, 0.83-0.97). These findings suggest an association between pre-miR-27a polymorphism rs895819 and cancer risk in Caucasians. The protective effect of rs895819 [G] allele in younger breast cancer and in the group of unilateral breast cancer patients await further confirmation since the included studies in this meta-analysis were limited.

• Korean Journal of Health Education and Promotion
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• v.26 no.1
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• pp.27-37
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• 2009

Objectives: This study was conducted to identify the relationship among knowledge, self-efficacy and compliance behavior on breast self examination(BSE) of female college students'. Methods: This descriptive study was conducted with a convenient sample of 499 female college student. Surveyed data collected from May to August 2008 were analyzed using descriptive statistics, t-test, pearson correlation coefficients and stepwise multiple regression. Results: The mean score of knowledge and self-efficacy concerning BSE was low, and compliance was high. The levels of knowledge, self-efficacy and compliance were differed significantly by experience of thinking about breast cancer, perceived susceptibility of breast cancer, experience of meeting with breast cancer patient, and educational experience of BSE. Significant correlations were found between knowledge and compliance, knowledge and compliance, knowledge and self-efficacy. Knowledge and self-efficacy were a powerful predictor of compliance. Conclusion: Focus on perceived knowledge, self-efficacy about breast self examination(BSE) of female college students may be beneficial to improve compliance, and should be reflected in the development of effective BSE education program.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6233-6239
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• 2013

Diabetes represents a serious health problem. In the diabetic state, alterations in metabolism, increased susceptibility to infections and immunological changes occur. The suppression of the immune response has been identified as a relevant factor that contributes to the increase in the rate of infections in these patients. At the same time, breast cancer is the most frequent malignant tumor in women. The molecular and cellular mechanisms underlying cancer development have revealed that immune cells functionally regulate epithelial cancer development and progression. Breastfeeding has been hypothesized to reduce the risk of breast cancer. However, early systematic reviews have not yielded consistent findings for this association. The demand for human milk is increasing due to the promotion and consumer acceptance of the health benefits of consuming a natural product rich in bioactive components. However, due to changes in glucose metabolism, the components of the milk from diabetic women are modified depending on the time of evaluation. In this literature review, we summarize important new findings revealing the paradoxical role of breastfeeding in preventing the onset of breast cancer in diabetic mothers. We hypothesized that the milk component production in diabetic mothers is affected by changes in glucose metabolism. Therefore, adequate maternal glycemic control and an adequate duration of breastfeeding for diabetic mothers are crucial to ensure that the immunity components are able to confer protection against breast cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.4
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• pp.1829-1832
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• 2016

Background: Breast cancer is the second most common malignancy among Nepalese women, accounting for 60% of the total cancer cases in females. Women diagnosed with germline mutations in BRCA1 like 185delAG, 1294del40 develop breast and/or ovarian cancer with a lifelong likelihood of up to 85% whereas presence of a mutation increases the risk for mutations to occur in other genes. The major objective of this study was to find the prevalence of these mutations in Nepalese cancer patients. Materials and Methods: This prospective study was carried out at two cancer hospitals in the Kathmandu valley over a period of 11 months. Irrespective of age group and stage of canceran appropriate amount of blood was withdrawn from 50 breast cancer patients and 20 controls. DNA was extracted manually and subjected to PCR using primers for 185delAG and 1294del40 mutations. PCR products were then digested with restriction enzyme (DdeII) followed by electrophoresis. Results: Prevalence of 185delAG in reference breast cancer patients was found to be 4/50 (8%) but no 1294del40 was apparent. Conclusions: Several mutations occurring in different exons of BRCA1 as well as mutations in other genes like BRCA2, for example, should also be taken in account.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.17
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• pp.7701-7705
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• 2015

Background: Thyroid hormones (TH) are regulated by the hypothalamic-pituitary axis, which plays an important role in cell growth, differentiation, development and other aspects of metabolism. It is believed that an active hypothalamic-pituitary axis increases the susceptibility of thyroid dysfunction during systemic chemotherapy. In order to investigate the relation between thyroid function and chemotherapy the present study was designed to investigate TH in breast cancer patients receiving at least three cycles of chemotherapy. The levels of TH were measured at the baseline and before each cycle of chemotherapy. Materials and Methods: Blood samples for estimation of TH levels were collected from 80 (pre-menopausal-40; post-menopausal-40) breast cancer patients just before they were undergoing - $1^{st}$, $2^{nd}$, $3^{rd}$ and $4^{th}$ cycle of chemotherapy. The serum was separated and $T_3$, $T_4$ and TSH levels were determined by chemiluminescence method. Results: $T_3$ and $T_4$ were found significantly decreased and TSH was found significantly increased after $1^{st}$ (p<0.001), $2^{nd}$ (p<0.0001) and $3^{rd}$ cycle of chemotherapy (p<0.0001). The variation of $T_3$ levels (decreased) and TSH levels (increased) was found more in post-menopausal (p<0.0001) women then in pre-menopausal women after $3^{rd}$ cycle of chemotherapy as compared to baseline (p<0.001). Conclusions: TH were remarkably altered after each cycle of chemotherapy leading to decline in thyroid function of breast cancer patients. Further, the results also indicated that post-menopausal women were more prone towards decline in thyroid function then pre-menopausal women. The present study proposes the monitoring of TH after each cycle of chemotherapy in breast cancer patients.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.5
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• pp.1707-1713
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• 2015

Eighty six cases of invasive ductal breast carcinomas were utilized to investigate GSTP1 polymorphisms in certain immunohistochemistry (IHC) subtypes of breast cancer with respect to ER, PR and HER2 expression. The frequency of wild allele homozygote, heterozygote and variant allele homozygote genotypes were 46.5%, 52.3% and 1.16% respectively; Whereas 54.3% of the control subjects were GSTP1 wild type allele homozygous, 40.0% were heterozygous and 5.71% mutant allele homozygous. There was dramatic inverted relation between positive IHC ER staining and increasing grade of tumors in general (100%, 88.6%, 40.4%) and especially among tumors with heterozygote genotype of GSTP1 (70%, 35.4%, 22.7). There was increase in positive IHC HER2 staining consistent with higher grades in general (20%, 29.6%, 50.0%), especially among tumors with GSTP1 wild allele homozygote genotype (5.0%, 9.1%, 31.8%). A remarkable reverse relation was also observed between the fraction of IHC hormone receptor phenotype ER+/PR+/ HER2- and increased grade of tumors (60.0%, 45.5%, and 27.3%) especially among tumors with GSTP1 heterozygote genotype, and a similar link was noted regarding ER+/PR-/ HER2- and tumor grade. There was increase in frequency of ER-/PR-/ HER2- (0.0%, 6.8%, and 18.2%) and ER-/PR-/ HER2+ (0.0%, 4.54%, and 40.9%) consistent with the higher grades of tumors in general and especially GSTP1 heterozygote genotype tumors. As a conclusion, there is no correlation between GSTP1 polymorphism and increased risk of breast cancer i.e. the mutant allele is randomly distributed in cancer and control cases. However, there is a link between GSTP1 genotypes and hormone receptor expression status and certain phenotypes of breast cancer, which may have clinical importance.