• Genomics & Informatics
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• 제3권4호
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• pp.159-165
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• 2005

The Korean Twin Register (n=154,783 pairs) was reported in 2002 as the first nationwide twin study in Korea and the largest study in Asia. The Twin Register has the information of disease outcomes since 1990, and basic clinical and questionnaire data from biennial health examination provided by Korea National Health Service. The author attempted to calculate some of the genetic parameters of cancers in this population. Common cancers in Korea known to have familial aggregation (colon and breast) and cancers of which familial aggregation is unclear (stomach cancer) were examined for their familial recurrence risks. There were 699 stomach cancers, 438 breast and 491 colorectal cancers cases in the twin register between 1991 and 2003. Like-sex twins showed recurrence risks (${\lambda}_{LS}$) of 5.1 (95% CI 3.7-6.9) for stomach cancers, 15.5 (95% CI1 0.9-20.2) for female breast cancers, and 28.1 (95% CI 23.5-34.4) for colon cancers. Colorectal cancers of female like-sex twins show significantly higher familial recurrence risk 40.7 (95% CI 34.6-47.4), suggesting higher genetic contribution in women than in men. The results show increased familial risks compared with previous studies from the same register and are largely compatible with other studies. The data of the Twin Register could be used for estimating population level genetic parameters, as well as base of the various studies.

• Asian Pacific Journal of Cancer Prevention
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• 제17권4호
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• pp.1987-1991
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• 2016

Breast cancer has emerged as the most prevalent cancer among women worldwide, including in Indonesia. The contribution of genes associated with high-risk breast-ovarian cancers, BRCA1 and BRCA2, in the Indonesian population is relatively unknown. We have characterized family history of patients with moderate- to high-risk of breast cancer predisposition in 26 unrelated cases from Indonesia for BRCA1/2 mutation analyses using direct sequencing. Known deleterious mutations were not found in either BRCA1 or BRCA2 genes. Seven variants in BRCA2 were documented in 10 of 26 patients (38%). All variants were categorized as unclassified (VUSs). Two synonymous variants, c.3623A>G and c.4035T>C, were found in 5 patients. One variant, c4600T>C, was found in a 38 year old woman with a family history of breast cancer. We have found 4 novel variants in BRCA2 gene including c.6718C>G, c.3281A>G, c.10176C>G, and c4490T>C in 4 unrelated patients, all of them having a positive family history of breast cancer. In accordance to other studies in Asian population, our study showed more frequent variants in BRCA2 compared to BRCA1. Further studies involving larger numbers of hereditary breast cancer patients are required to reveal contribution of BRCA1/2 mutations and/or other predisposing genes among familial breast cancer patients in Indonesia.

• Asian Pacific Journal of Cancer Prevention
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• 제13권6호
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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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• 제14권10호
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• pp.5625-5629
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• 2013

Occurrence of breast cancer is related to genetic as well as cultural, environmental and life-style factors. Variations in diversity of these factors among different ethnic groups and geographical areas emphasize the immense need for studies in all racial-ethnic populations. The incidence of breast cancer in Pakistan is highest in Asians after Jews in Israel and 2.5 times higher than that in neighboring countries like Iran and India, accounting for 34.6% of female cancers. The Pakistani population is deficient in information regarding breast cancer etiology and epidemiology, but efforts done so far had suggested consanguinity as a major risk factor for frequent mutations leading to breast cancer and has also shed light on genetic origins in different ethnic groups within Pakistan. World-wide research efforts on different ethnicities have enhanced our understanding of genetic predisposition to breast cancer but despite these discoveries, 75% of the familial risk of breast cancer remains unexplained, highlighting the fact that the majority of breast cancer susceptibility genes remain unidentified. For this purpose Pakistani population provides a strong genetic pool to elucidate the genetic etiology of breast cancer because of cousin marriages. In this review, we describe the known breast cancer predisposition factors found in the local Pakistani population and the epidemiological research work done to emphasize the importance of exploring factors/variants contributing to breast cance, in order to prevent, cure and decrease its incidence in our country.

• Asian Pacific Journal of Cancer Prevention
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• 제15권19호
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• pp.8319-8324
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• 2014

Although genetic markers identifying women at an increased risk of developing breast cancer exist, the majority of inherited risk factors remain elusive. Mutations in the BRCA1/BRCA2 gene confer a substantial increase in breast cancer risk, yet routine clinical genetic screening is limited to the coding regions and intronexon boundaries, precluding the identification of mutations in noncoding and untranslated regions. Because 3' untranslated region (3'UTR) polymorphisms disrupting microRNA (miRNA) binding can be functional and can act as genetic markers of cancer risk, we aimed to determine genetic variation in the 3'UTR of BRCA1/BRCA2 in familial and early-onset breast cancer patients with and without mutations in the coding regions of BRCA1/BRCA2 and to identify specific 3'UTR variants that may be risk factors for cancer development. The 3'UTRs of the BRCA1 and BRCA2 genes were screened by heteroduplex analysis and DNA sequencing in 100 patients from 46 BRCA1/2 families, 54 non-BRCA1/2 families, and 47 geographically matched controls. Two polymorphisms were identified. SNPs $c.^*1287C$ >T (rs12516) (BRCA1) and $c.^*105A$ >C (rs15869) (BRCA2) were identified in 27% and 24% of patients, respectively. These 2 variants were also identified in controls with no family history of cancer (23.4% and 23.4%, respectively). In comparison to variations in the 3'UTR region of the BRCA1/2 genes and the BRCA1/2 mutational status in patients, there was a statistically significant relationship between the BRCA1 gene polymorphism $c.^*1287C$ >T (rs12516) and BRCA1 mutations (p=0.035) by Fisher's Exact Test. SNP $c.^*1287C$ >T (rs12516) of the BRCA1 gene may have potential use as a genetic marker of an increased risk of developing breast cancer and likely represents a non-coding sequence variation in BRCA1 that impacts BRCA1 function and leads to increased early-onset and/or familial breast cancer risk in the Turkish population.

• Asian Pacific Journal of Cancer Prevention
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• 제16권5호
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• pp.1719-1724
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• 2015

Background: Breast and cervical cancers are the most common types of cancer in women worldwide. Previous studies in Asia have shown that related knowledge and awareness is low among female university students. The goal of this study was to assess breast and cervical cancer knowledge, practices, and awareness among female university students in Samsun,Turkey. Materials and Methods: This research was a cross-sectional survey of female university students using a self-administered. questionnaire to investigate participant awareness and knowledge of breast and cervical cancer. A total of 301 female university students participated. Descriptive statistics and chi square tests were used for data analysis. Results: The mean age of the participants in this study was $22.0{\pm}5.91$ years. Regarding family history, 89.7 % of the students had no known familial history of breast cancer. Students (65.4%) had knowledge about breast self examination and 52.2 % of them had performed breast self examinationm while 55.1% of them had knowledge about prevention of cervical cancer. Conclusions: Although the results are preliminary, the study points to an insufficient knowledge of university students in Samsun about breast and cervical cancer.

• Asian Pacific Journal of Cancer Prevention
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• 제16권9호
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• pp.4051-4055
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• 2015

The purpose of this study is to assess the effect of consanguinity on breast cancer incidence in Tunisia. We conducted a case-control study to evaluate the involvement of heterozygote and homozygote haplotypes of BRCA1 gene SNPs according to consanguinity among 40 cases of familial breast cancer, 46 cases with sporadic breast cancer and 34 healthy controls. We showed significant difference in consanguinity rate between breast cancer patients versus healthy controls P=0.001. Distribution of homozygous BRCA1 haplotypes among healthy women versus breast cancer patients was significantly different; p=0.02. Parental consanguinity seems to protect against breast cancer in the Tunisian population.

• Asian Pacific Journal of Cancer Prevention
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• 제17권4호
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• pp.2195-2198
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• 2016

Background: Breast cancer is the most prevalent malignancy among women with wide differences in clinical profile from region to region. The present study aimed to describe the profile of breast cancer patients attending a tertiary care hospital in Marathwada region of Western India. Materials and Methods: In this descriptive retrospective study, we reviewed records of pathologically diagnosed patients of breast cancer managed at our center from years 2009 to 2015. Data with respect to demographic status, detailed past, medical, familial and personal history, findings of clinical examination and histological features were obtained. Patients were staged according to the Tumor Node Metastasis (TNM) system. Results: Among 260 cases, mean age of presentation was 52.6, with average age of menarche of 11.3 and menopause of 52.6 years. The majority of patients were from urban regions and were postmenopausal (64.3%). Main clinical features presentation were breast lumps. Most patients were in stage II and had infiltrating duct carcinomas. Conclusions: Most common risk factors for breast cancer observed are increasing age, low parity and obesity. Breast cancer was more prevalent among postmenopausal women presenting in stage II with infiltating duct carcinoma in our region of India.

• Asian Pacific Journal of Cancer Prevention
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• 제16권9호
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• pp.3685-3690
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• 2015

Background: Low-dose oral contraceptives (OC) were approved by the Japanese Ministry of Health, Labor and Welfare in 1999, yet despite their contraceptive and non-contraceptive health benefits, only 5% of the target population use them. Fear of increased cancer risk, particularly breast cancer, is one reason for this. Due to low OC uptake and low screening participation, a paucity of data is available on the risk of OC use and breast cancer in Japanese women. The present study investigated OC use and breast cancer risk, as well as menstrual, reproductive and family factors. Materials and Methods: This was a clinic-based case-control study of women aged 20-69yrs who had undergone breast screening between January 2007 and December 2013 in central Tokyo. In all, 28.8% of the participants had experience with OC use. Cases were 155 women with a pathologically confirmed diagnosis of breast cancer. Controls were the remaining 12,333 women. Results: Increased age was a significant risk factor for breast cancer (p<0.001). A lower risk was found in premenopausal women presently taking OC compared to never users (OR 0.45; 95% CI 0.22-0.90) after adjusting for age, parity and breast feeding, and a family history of breast cancer. Conclusions: Increased age rather than OC use had a greater effect on breast cancer risk. This risk may be decreased in premenopausal women with OC use, but further long-term prospective studies are necessary.

• Asian Pacific Journal of Cancer Prevention
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• 제14권2호
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• pp.723-726
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• 2013

Background: Breast cancer is worldwide the most common cancer in women and is a major public health problem. Genes with high or low penetrance are now clearly implicated in the onset of breast cancer, mostly the BRCA genes. All women in families at high risk of breast cancer do not develop tumours, even when they carry the familial mutation, suggesting the existence of genetic and environmental protective factors. Several studies have shown that consanguinity is linked to a decreased or an increased risk of breast cancer, but to the best of our knowledge, there is no study concerning the association between consanguinity and the occurrence of tumours in women with high risk of breast cancer. The objective of this study was to examine whether parental consanguinity in families with genetic predisposition to breast cancer affect the risk of siblings for having this cancer. Materials and Methods: Over a six-year period, 72 different patients with a histological diagnosis of breast or ovarian cancer from 42 families were recruited for genetic counselling to the Department of Medical Genetics, Rabat. Consanguinity rate was determined in cases and compared to the consanguinity rate in the Moroccan general population. Results: Consanguinity rates were 9.72% in patients and 15.3% in controls, but the difference was statistically not significant (p>0.001) and the mean coefficient of consanguinity was lower in breast cancer patients (0.0034) than in controls (0.0065). Conclusions: Despite the relatively small sample size of the current study, our results suggest that parental consanguinity in Moroccan women might not be associated with an altered risk of breast cancer. Large scale studies should be carried out to confirm our results and to develop public health programs.