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A new BRCA1 germline mutation (E879X) in a Malaysian breast cancer patient of Chinese descent

Khoo AS, Balraj P, Volpi L, Nair S

Hum Mutat, 2000 May;15(5):485.
PMID: 10790221
Matched MeSH terms: Germ-Line Mutation/genetics*
BRCA1 c.2845insA is a recurring mutation with a founder effect in Singapore Malay women with early onset breast/ovarian cancer

Sng JH, Ali AB, Lee SC, Zahar D, Wong JE, Blake V, et al.

J Med Genet, 2003 Oct;40(10):e117.
PMID: 14569140
Matched MeSH terms: Germ-Line Mutation
Fulltext Germline RET mutations in exons 10 and 11: an Iranian survey of 57 medullary thyroid carcinoma cases

Hedayati M, Nabipour I, Rezaei-Ghaleh N, Azizi F

Med J Malaysia, 2006 Dec;61(5):564-9.
PMID: 17623957

The susceptibility gene for hereditary Medullary Thyroid Carcinoma (MTC) is the RET proto-oncogene. The aim of this study was to evaluate the prevalence of common germline RET mutations in exons 10 and 11 among Iranian MTC patients. Fifty-seven non-related MTC patients were examined in this study (Females: Males =1.2:1.0, Mean age = 40.0 +/- 11.5 years) and the existence of mutations was assessed through the PCR-RFLP technique. The only Multiple Endocrine Neoplasia type 2A (MEN2A) patient displayed a C634W mutation in exon 11. Among 53 apparently sporadic MTC patients, one patient showed a C620R mutation in exon 10 and two other patients displayed C624Y mutations in exon 11 of RET proto-oncogene. Neither the only Multiple Endocrine Neoplasia type 2B (MEN2B) patient nor two Familial MTC patients was found to carry germline mutations in exons 10 and 11. This study reports, for the first time, the prevalence of common RET mutations among Iranian, apparently sporadic MTC patients, underlining the critical importance of screening for RET mutations in such patients.

Matched MeSH terms: Germ-Line Mutation*
Fulltext BRCA1 and BRCA2 germline mutations in Malaysian women with early-onset breast cancer without a family history

Toh GT, Kang P, Lee SS, Lee DS, Lee SY, Selamat S, et al.

PLoS One, 2008;3(4):e2024.
PMID: 18431501 DOI: 10.1371/journal.pone.0002024

BACKGROUND: In Asia, breast cancer is characterised by an early age of onset: In Malaysia, approximately 50% of cases occur in women under the age of 50 years. A proportion of these cases may be attributable, at least in part, to genetic components, but to date, the contribution of genetic components to breast cancer in many of Malaysia's ethnic groups has not been well-characterised.
METHODOLOGY: Given that hereditary breast carcinoma is primarily due to germline mutations in one of two breast cancer susceptibility genes, BRCA1 and BRCA2, we have characterised the spectrum of BRCA mutations in a cohort of 37 individuals with early-onset disease (

Matched MeSH terms: Germ-Line Mutation*
Fulltext Identification of novel large genomic rearrangements at the BRCA1 locus in Malaysian women with breast cancer

Sharifah NA, Nurismah MI, Lee HC, Aisyah AN, Clarence-Ko CH, Naqiyah I, et al.

Cancer Epidemiol, 2010 Aug;34(4):442-7.
PMID: 20451485 DOI: 10.1016/j.canep.2010.04.010

The incidence of breast cancer has been on the rise in Malaysia. It is suggested that a subset of breast cancer cases were associated with germline mutation in breast cancer susceptibility (BRCA) genes. Most of the BRCA mutations reported in Malaysia were point mutations, small deletions and insertions. Here we report the first study of BRCA large genomic rearrangements (LGRs) in Malaysia. We aimed to detect the presence of LGRs in the BRCA genes of Malaysian patients with breast cancer.

Matched MeSH terms: Germ-Line Mutation/genetics
Mismatch repair genes expression defects & association with clinicopathological characteristics in colorectal carcinoma

Kaur G, Masoud A, Raihan N, Radzi M, Khamizar W, Kam LS

Indian J Med Res, 2011 Aug;134:186-92.
PMID: 21911971

DNA mismatch repair gene (MMR) abnormalities are seen in 95 per cent of hereditary nonpolyposis colorectal cancer (HNPCC) and 10-15 per cent of sporadic colorectal cancers. There are no data on MMR abnormalities in Malaysian colorectal cancer patients. This study was aimed to determine the frequency of abnormal MMR gene protein expression in colorectal carcinoma in Northern Peninsular Malaysia using immunohistochemistry.

Matched MeSH terms: Germ-Line Mutation/genetics
Fulltext Germline mutation analysis of MLH1 and MSH2 in Malaysian Lynch syndrome patients

Zahary MN, Kaur G, Abu Hassan MR, Singh H, Naik VR, Ankathil R

World J Gastroenterol, 2012 Feb 28;18(8):814-20.
PMID: 22371642 DOI: 10.3748/wjg.v18.i8.814

To investigate the protein expression profile of mismatch repair (MMR) genes in suspected cases of Lynch syndrome and to characterize the associated germline mutations.

Matched MeSH terms: Germ-Line Mutation*
Childhood adrenocortical carcinoma as a sentinel cancer for detecting families with germline TP53 mutations

Choong SS, Latiff ZA, Mohamed M, Lim LL, Chen KS, Vengidasan L, et al.

Clin Genet, 2012 Dec;82(6):564-8.
PMID: 22233476 DOI: 10.1111/j.1399-0004.2012.01841.x

Li-Fraumeni syndrome (LFS) is a highly penetrant, autosomal dominant disorder where affected individuals carry a 50% risk of developing cancer before 30 years of age. It is most commonly associated with mutations in the tumour suppressor gene, TP53. Adrenocortical carcinoma (ACC) is a very rare paediatric cancer, and up to 80% of affected children are found to carry germline TP53 mutations. Hence, we propose using childhood ACC incidence as selection criteria for referral for TP53 mutation testing, independent of familial cancer history. Under the auspices of the Malaysian Society of Paediatric Haematology-Oncology, four eligible children diagnosed with ACC over a 30-month study period were referred for mutation testing. Three had a germline TP53 mutation. Subsequent TP53 testing in relatives showed two inherited mutations and one de novo mutation. These findings strongly support paediatric ACC as a useful sentinel cancer for initiating a germline TP53/LFS detection programme, particularly in countries where the lack of structured oncogenetic practice precludes the identification of families with LFS features.

Matched MeSH terms: Germ-Line Mutation/genetics*
Fulltext Comparable frequency of BRCA1, BRCA2 and TP53 germline mutations in a multi-ethnic Asian cohort suggests TP53 screening should be offered together with BRCA1/2 screening to early-onset breast cancer patients

Lee DS, Yoon SY, Looi LM, Kang P, Kang IN, Sivanandan K, et al.

Breast Cancer Res, 2012;14(2):R66.
PMID: 22507745

Germline TP53 mutations cause an increased risk to early-onset breast cancer in Li-Fraumeni syndrome (LFS) families and the majority of carriers identified through breast cancer cohorts have LFS or Li-Fraumeni-like (LFL) features. However, in Asia and in many low resource settings, it is challenging to obtain accurate family history and we, therefore, sought to determine whether the presence of early-onset breast cancer is an appropriate selection criteria for germline TP53 testing.

Matched MeSH terms: Germ-Line Mutation*
Fulltext Prevalence of PALB2 mutations in breast cancer patients in multi-ethnic Asian population in Malaysia and Singapore

Phuah SY, Lee SY, Kang P, Kang IN, Yoon SY, Thong MK, et al.

PLoS One, 2013;8(8):e73638.
PMID: 23977390 DOI: 10.1371/journal.pone.0073638

The partner and localizer of breast cancer 2 (PALB2) is responsible for facilitating BRCA2-mediated DNA repair by serving as a bridging molecule, acting as the physical and functional link between the breast cancer 1 (BRCA1) and breast cancer 2 (BRCA2) proteins. Truncating mutations in the PALB2 gene are rare but are thought to be associated with increased risks of developing breast cancer in various populations.

Matched MeSH terms: Germ-Line Mutation/genetics*
Germline mutation and protein expression analysis of mismatch repair genes MSH6 and PMS2 in Malaysian Lynch syndrome patients

Zahary MN, Kaur G, Hassan MR, Sidek AS, Singh H, Yeh LY, et al.

Int J Colorectal Dis, 2014 Feb;29(2):261-2.
PMID: 24072394 DOI: 10.1007/s00384-013-1770-1
Matched MeSH terms: Germ-Line Mutation/genetics*
Fulltext A review of colorectal cancer research in Malaysia

Lim KG

Med J Malaysia, 2014 Aug;69 Suppl A:23-32.
PMID: 25417948 MyJurnal

105 articles related to colorectal cancer(CRC) were found in a search through a database dedicated to indexing all original data relevant to medicine published in Malaysia between the years 2000-2013. 56 articles were selected and reviewed on the basis of clinical relevance and future research implications. Research into the genetic basis for colorectal cancer included studies in germline mutations of known syndromes as well as polymorphisms that conferred individuals a higher odds ratio for developing CRC. Several studies also documented the variety of somatic mutations seen in cases of sporadic CRC in Malaysia. Studies into the knowledge and attitudes of Malaysians regarding CRC revealed poor appreciation of the common symptoms, risk factors and available measures for its early detection. This may explain the observed facts that more Malaysians present with late stage CRC than seen in developed countries. The small amount of data recorded concerning the outcome of treatment also suggests overall survival of Malaysian CRC patients for comparable stage of CRC is lower than achieved in developed countries.

Matched MeSH terms: Germ-Line Mutation
Fulltext Whole-genome sequencing analysis of phenotypic heterogeneity and anticipation in Li-Fraumeni cancer predisposition syndrome

Ariffin H, Hainaut P, Puzio-Kuter A, Choong SS, Chan AS, Tolkunov D, et al.

Proc Natl Acad Sci U S A, 2014 Oct 28;111(43):15497-501.
PMID: 25313051 DOI: 10.1073/pnas.1417322111

The Li-Fraumeni syndrome (LFS) and its variant form (LFL) is a familial predisposition to multiple forms of childhood, adolescent, and adult cancers associated with germ-line mutation in the TP53 tumor suppressor gene. Individual disparities in tumor patterns are compounded by acceleration of cancer onset with successive generations. It has been suggested that this apparent anticipation pattern may result from germ-line genomic instability in TP53 mutation carriers, causing increased DNA copy-number variations (CNVs) with successive generations. To address the genetic basis of phenotypic disparities of LFS/LFL, we performed whole-genome sequencing (WGS) of 13 subjects from two generations of an LFS kindred. Neither de novo CNV nor significant difference in total CNV was detected in relation with successive generations or with age at cancer onset. These observations were consistent with an experimental mouse model system showing that trp53 deficiency in the germ line of father or mother did not increase CNV occurrence in the offspring. On the other hand, individual records on 1,771 TP53 mutation carriers from 294 pedigrees were compiled to assess genetic anticipation patterns (International Agency for Research on Cancer TP53 database). No strictly defined anticipation pattern was observed. Rather, in multigeneration families, cancer onset was delayed in older compared with recent generations. These observations support an alternative model for apparent anticipation in which rare variants from noncarrier parents may attenuate constitutive resistance to tumorigenesis in the offspring of TP53 mutation carriers with late cancer onset.

Matched MeSH terms: Germ-Line Mutation/genetics
Polymorphisms of cell cycle regulator genes CCND1 G870A and TP53 C215G: Association with colorectal cancer susceptibility risk in a Malaysian population

Zahary MN, Ahmad Aizat AA, Kaur G, Yeong Yeh L, Mazuwin M, Ankathil R

Oncol Lett, 2015 Nov;10(5):3216-3222.
PMID: 26722315

Colorectal cancer (CRC) occurs as a more common sporadic form and a less common familial form. Our earlier analysis of germline mutations of mismatch repair genes confirmed only 32% of familial CRC cases as Lynch syndrome cases. It was hypothesized that the remaining familial aggregation may be 'polygenic' due to single nucleotide polymorphisms (SNPs) of low penetrance genes involved in cancer predisposition pathways, such as cell cycle regulation and apoptosis pathways. The current case-control study involving 104 CRC patients (52 sporadic and 52 familial) and 104 normal healthy controls investigated the contribution of the SNPs cyclin D1 (CCND1) G870A and tumor protein p53 (TP53) C215G in modulating familial and sporadic CRC susceptibility risk. DNA was extracted from peripheral blood and the polymorphisms were genotyped by employing a polymerase chain reaction-restriction fragment length polymorphism method. The association between these polymorphisms and CRC susceptibility risk was calculated using a binary logistic regression analysis and deriving odds ratios (ORs). The A/A variant genotype of CCND1 and G/G variant genotype of TP53 exhibited a significantly greater association with the risk of sporadic CRC [CCND1: OR, 3.471; 95% confidence interval (CI), 1.443-8.350; P=0.005. TP53: OR, 2.829; CI, 1.119-7.152; P=0.026] as well as familial CRC susceptibility (CCND1: OR, 3.086; CI, 1.270-7.497; P=0.019. TP53: OR, 3.048; CI, 1.147-8.097; P=0.030). The results suggest a potential role of the SNPs CCND1 G870A and TP53 C215G in the modulation of sporadic and familial CRC susceptibility risk.

Matched MeSH terms: Germ-Line Mutation
Spectrum of germ-line RB1 gene mutations in Malaysian patients with retinoblastoma

Mohd Khalid MK, Yakob Y, Md Yasin R, Wee Teik K, Siew CG, Rahmat J, et al.

Mol Vis, 2015;21:1185-90.
PMID: 26539030

The availability of molecular genetic testing for retinoblastoma (RB) in Malaysia has enabled patients with a heritable predisposition to the disease to be identified, which thus improves the clinical management of these patients and their families. In this paper, we presented our strategy for performing molecular genetic testing of the RB1 gene and the findings from our first 2 years of starting this service.

Matched MeSH terms: Germ-Line Mutation*
Comprehensive spectrum of BRCA1 and BRCA2 deleterious mutations in breast cancer in Asian countries

Kwong A, Shin VY, Ho JC, Kang E, Nakamura S, Teo SH, et al.

J Med Genet, 2016 Jan;53(1):15-23.
PMID: 26187060 DOI: 10.1136/jmedgenet-2015-103132

Approximately 5%-10% of breast cancers are due to genetic predisposition caused by germline mutations; the most commonly tested genes are BRCA1 and BRCA2 mutations. Some mutations are unique to one family and others are recurrent; the spectrum of BRCA1/BRCA2 mutations varies depending on the geographical origins, populations or ethnic groups. In this review, we compiled data from 11 participating Asian countries (Bangladesh, Mainland China, Hong Kong SAR, Indonesia, Japan, Korea, Malaysia, Philippines, Singapore, Thailand and Vietnam), and from ethnic Asians residing in Canada and the USA. We have additionally conducted a literature review to include other Asian countries mainly in Central and Western Asia. We present the current pathogenic mutation spectrum of BRCA1/BRCA2 genes in patients with breast cancer in various Asian populations. Understanding BRCA1/BRCA2 mutations in Asians will help provide better risk assessment and clinical management of breast cancer.

Matched MeSH terms: Germ-Line Mutation*
Evaluation of germline BRCA1 and BRCA2 mutations in a multi-ethnic Asian cohort of ovarian cancer patients

Hasmad HN, Lai KN, Wen WX, Park DJ, Nguyen-Dumont T, Kang PCE, et al.

Gynecol Oncol, 2016 05;141(2):318-322.
PMID: 26541979 DOI: 10.1016/j.ygyno.2015.11.001

OBJECTIVE: Despite the discovery of breast and ovarian cancer predisposition genes BRCA1 and BRCA2 more than two decades ago, almost all the available data relate to women of European ancestry, with only a handful of studies in Asian populations. In this study, we determined the frequency of germline alterations in BRCA1 and BRCA2 in ovarian cancer patients from a multi-ethnic cross-sectional cohort of Asian ovarian cancer patients from Malaysia.
METHODS: From October 2008 to February 2015, we established a hospital-based cohort of ovarian cancer patients and the germline status of all 218 women with invasive epithelial ovarian cancer was tested using targeted amplification and sequencing of the intron-exon junctions and exonic sequences of BRCA1, BRCA2, PALB2 and TP53.
RESULTS: BRCA1 and BRCA2 mutations were found in 8% (17 cases) and 3% (7 cases) of the ovarian cancer patients, respectively. Mutation carriers were diagnosed at a similar age to non-carriers, but were more likely to be Indian, have serous ovarian cancer, and have more relatives with breast or ovarian cancer. Nonetheless, 42% (10/24) of mutation carriers did not have any family history of breast or ovarian cancer and offering genetic counselling and genetic testing only to women with family history would mean that 35% (6/17) of BRCA1 mutation carriers and 57% (4/7) of BRCA2 mutation carriers would not be offered genetic testing.
CONCLUSIONS: Our data suggest that, similar to Caucasians, a significant proportion of Asian ovarian cancer was attributed to germline mutations in BRCA1 and to a lesser extent in BRCA2.

Matched MeSH terms: Germ-Line Mutation*
Fulltext Germline APOBEC3B deletion is associated with breast cancer risk in an Asian multi-ethnic cohort and with immune cell presentation

Wen WX, Soo JS, Kwan PY, Hong E, Khang TF, Mariapun S, et al.

Breast Cancer Res, 2016 05 27;18(1):56.
PMID: 27233495 DOI: 10.1186/s13058-016-0717-1

BACKGROUND: APOBEC3B is a cytosine deaminase implicated in immune response to viral infection, cancer predisposition and carcinogenesis. Germline APOBEC3B deletion is more common in East Asian women and confers a modest risk to breast cancer in both East Asian and Caucasian women. Analysis of tumour samples from women of European descent has shown that germline APOBEC3B deletion is associated with an increased propensity to develop somatic mutations and with an enrichment for immune response-related gene sets. However, this has not been examined in Asian tumour samples, where population differences in genetic and dietary factors may have an impact on the immune system.
METHODS: In this study, we determined the prevalence of germline APOBEC3B deletion and its association with breast cancer risk in a cross-sectional hospital-based Asian multi-ethnic cohort of 1451 cases and 1442 controls from Malaysia. We compared gene expression profiles of breast cancers arising from APOBEC3B deletion carriers and non-carriers using microarray analyses. Finally, we characterised the overall abundance of tumour-infiltrating immune cells in breast cancers from TCGA and METABRIC using ESTIMATE and relative frequency of 22 immune cell subsets in breast cancers from METABRIC using CIBERSORT.
RESULTS: The minor allelic frequency of APOBEC3B deletion was estimated to be 0.35, 0.42 and 0.16 in female populations of Chinese, Malay and Indian descent, respectively, and that germline APOBEC3B deletion was associated with breast cancer risk with odds ratios of 1.23 (95 % CI: [1.05, 1.44]) for one-copy deletion and 1.38 (95 % CI: [1.10, 1.74]) for two-copy deletion compared to women with no deletion. Germline APOBEC3B deletion was not associated with any clinicopathologic features or the expression of any APOBEC family members but was associated with immune response-related gene sets (FDR q values

Matched MeSH terms: Germ-Line Mutation*
Fulltext Functional single nucleotide polymorphisms within the cyclin-dependent kinase inhibitor 2A/2B region affect pancreatic cancer risk

Campa D, Pastore M, Gentiluomo M, Talar-Wojnarowska R, Kupcinskas J, Malecka-Panas E, et al.

Oncotarget, 2016 08 30;7(35):57011-57020.
PMID: 27486979 DOI: 10.18632/oncotarget.10935

The CDKN2A (p16) gene plays a key role in pancreatic cancer etiology. It is one of the most commonly somatically mutated genes in pancreatic cancer, rare germline mutations have been found to be associated with increased risk of developing familiar pancreatic cancer and CDKN2A promoter hyper-methylation has been suggested to play a critical role both in pancreatic cancer onset and prognosis. In addition several unrelated SNPs in the 9p21.3 region, that includes the CDNK2A, CDNK2B and the CDNK2B-AS1 genes, are associated with the development of cancer in various organs. However, association between the common genetic variability in this region and pancreatic cancer risk is not clearly understood. We sought to fill this gap in a case-control study genotyping 13 single nucleotide polymorphisms (SNPs) in 2,857 pancreatic ductal adenocarcinoma (PDAC) patients and 6,111 controls in the context of the Pancreatic Disease Research (PANDoRA) consortium. We found that the A allele of the rs3217992 SNP was associated with an increased pancreatic cancer risk (ORhet=1.14, 95% CI 1.01-1.27, p=0.026, ORhom=1.30, 95% CI 1.12-1.51, p=0.00049). This pleiotropic variant is reported to be a mir-SNP that, by changing the binding site of one or more miRNAs, could influence the normal cell cycle progression and in turn increase PDAC risk. In conclusion, we observed a novel association in a pleiotropic region that has been found to be of key relevance in the susceptibility to various types of cancer and diabetes suggesting that the CDKN2A/B locus could represent a genetic link between diabetes and pancreatic cancer risk.

Matched MeSH terms: Germ-Line Mutation
Identification of germline alterations in breast cancer predisposition genes among Malaysian breast cancer patients using panel testing

Ng PS, Wen WX, Fadlullah MZ, Yoon SY, Lee SY, Thong MK, et al.

Clin Genet, 2016 10;90(4):315-23.
PMID: 26757417 DOI: 10.1111/cge.12735

Although an association between protein-truncating variants and breast cancer risk has been established for 11 genes, only alterations in BRCA1, BRCA2, TP53 and PALB2 have been reported in Asian populations. Given that the age of onset of breast cancer is lower in Asians, it is estimated that inherited predisposition to breast cancer may be more significant. To determine the potential utility of panel testing, we investigated the prevalence of germline alterations in 11 established and 4 likely breast cancer genes in a cross-sectional hospital-based cohort of 108 moderate to high-risk breast cancer patients using targeted next generation sequencing. Twenty patients (19%) were identified to carry deleterious mutations, of whom 13 (12%) were in the BRCA1 or BRCA2, 6 (6%) were in five other known breast cancer predisposition genes and 1 patient had a mutation in both BRCA2 and BARD1. Our study shows that BRCA1 and BRCA2 account for the majority of genetic predisposition to breast cancer in our cohort of Asian women. Although mutations in other known breast cancer genes are found, the functional significance and breast cancer risk have not yet been determined, thus limiting the clinical utility of panel testing in Asian populations.

Matched MeSH terms: Germ-Line Mutation*

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