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Muhammad N, Azeem A, Bakar MA, Prajzendanc K, Loya A, Jakubowska A, Hamann U, Rashid MU. Contribution of constitutional BRCA1 promoter methylation to early-onset and familial breast cancer patients from Pakistan. Breast Cancer Res Treat 2023; 202:377-387. [PMID: 37528266 DOI: 10.1007/s10549-023-07068-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Accepted: 07/20/2023] [Indexed: 08/03/2023]
Abstract
PURPOSE Constitutional BRCA1 promoter methylation has been identified as a potential risk factor for breast cancer (BC) in the Caucasian population. However, this data is lacking for BC patients of Asian origin. Therefore, we assessed the contribution of constitutional BRCA1 promoter methylation in Pakistani BC patients. METHODS A total of 385 BRCA1/2-negative index BC patients (197 early-onset BC (≤ 30 years), 152 familial BC, 17 familial BC and ovarian cancer, 19 male BC) and 107 healthy controls were screened for the constitutional BRCA1 promoter methylation by methylation-sensitive high-resolution melting assay. Overall, 131 patients displayed triple-negative BC (TNBC) and 254 non-TNBC phenotypes. The prevalence of BRCA1 promoter methylation was calculated based on clinicopathological characteristics using univariable and multivariable logistic regression models. RESULTS Constitutional BRCA1 promoter methylation was identified in 19.5% (75/385) of BC patients and 13.1% (14/107) of controls. The frequency of methylation was higher in early-onset BC (23.4% vs. 13.1%, P = 0.035) and TNBC patients (29.0% vs. 13.1%, P = 0.004) compared to controls. Methylation was also more prevalent in patients with high-grade than low-grade tumors (21.7% vs. 12.2%, P = 0.034) and progesterone receptor (PR)-negative than PR-positive tumors (26.0% vs. 13.9%, P = 0.004). Constitutional BRCA1 promoter methylation remained independently associated with TNBC phenotype (odds ratio 1.99; 95% CI 1.12-3.54; P = 0.02) after adjusting for BC diagnosis age, tumor grade, ER, and PR status. CONCLUSION Constitutional BRCA1 promoter methylation is associated with TNBC and can serve as a non-invasive blood-based biomarker for Pakistani TNBC patients.
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Affiliation(s)
- Noor Muhammad
- Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH&RC), 7-A, Block R-3, Johar Town, Lahore, 54770, Pakistan
| | - Ayesha Azeem
- Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH&RC), 7-A, Block R-3, Johar Town, Lahore, 54770, Pakistan
| | - Muhammad Abu Bakar
- Department of Cancer Registry and Clinical Data Management, SKMCH&RC, Lahore, Pakistan
| | - Karolina Prajzendanc
- Department of Genetics and Pathology, Pomeranian Medical University, Szczecin, Poland
| | - Asif Loya
- Department of Pathology, SKMCH&RC, Lahore, Pakistan
| | - Anna Jakubowska
- Department of Genetics and Pathology, Pomeranian Medical University, Szczecin, Poland
- Independent Laboratory of Molecular Biology and Genetic Diagnostics, Pomeranian Medical University, Szczecin, Poland
| | - Ute Hamann
- Molecular Genetics of Breast Cancer, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Muhammad Usman Rashid
- Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH&RC), 7-A, Block R-3, Johar Town, Lahore, 54770, Pakistan.
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Rashid MU, Muhammad N, Shehzad U, Khan FA, Loya A, Hamann U. Prevalence of FANCM germline variants in BRCA1/2 negative breast and/or ovarian cancer patients from Pakistan. Fam Cancer 2023; 22:31-41. [PMID: 35802266 DOI: 10.1007/s10689-022-00304-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 06/18/2022] [Indexed: 01/12/2023]
Abstract
The Fanconi anemia complementation group M (FANCM) gene is a potential candidate for breast/ovarian cancer susceptibility in European populations. Here, we examined the contribution of FANCM germline variants to hereditary breast and/or ovarian cancer in Pakistan. Comprehensive FANCM variant screening was performed in 201 BRCA1 and BRCA2 (BRCA1/2) negative Pakistani patients with and without triple-negative breast cancer (TNBC) and/or ovarian cancer, using denaturing high-performance liquid chromatography analysis (DHPLC) followed by DNA sequencing. Novel variants were tested for their potential effect on protein function using in silico tools. Reverse transcription (RT)-PCR analysis of RNA extracted from one deletion/insertion (delins) variant (p.K1780delinsNGIT) carrier and three non-carriers was performed to evaluate the impact of this variant on splicing. Furthermore, potentially functional variants were evaluated in 200 healthy female controls. A missense variant (p.V1857M) was identified in a 50-year-old TNBC patient with a family history of breast cancer. It was also identified in the index patient´s daughter, who was diagnosed with osteosarcoma at 15 years of age. Further, one delins variant (p.K1780delinsNGIT) was identified in a 45-year-old non-TNBC patient, but not detected in her brother, who was diagnosed with Hodgkin's lymphoma at 38 years of age. Based on in silico and RNA analyses, p.V1857M and p.K1780delinsNGIT were predicted as variants of uncertain significance (VUS), respectively. Both variants were absent in 200 healthy controls. Our findings suggest a marginal contribution of FANCM variants to hereditary breast/ovarian cancer in Pakistan, which need to be confirmed in larger studies.
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Affiliation(s)
- Muhammad Usman Rashid
- Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH&RC), 7A, Block R3, Johar Town, Lahore, 54000, Punjab, Pakistan.
| | - Noor Muhammad
- Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH&RC), 7A, Block R3, Johar Town, Lahore, 54000, Punjab, Pakistan
| | - Umara Shehzad
- Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH&RC), 7A, Block R3, Johar Town, Lahore, 54000, Punjab, Pakistan
| | - Faiz Ali Khan
- Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH&RC), 7A, Block R3, Johar Town, Lahore, 54000, Punjab, Pakistan
| | - Asif Loya
- Department of Pathology, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH&RC), Lahore, Pakistan
| | - Ute Hamann
- Molecular Genetics of Breast Cancer, German Cancer Research Center (DKFZ), Heidelberg, Germany
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Muhammad N, Sadaqat R, Naeemi H, Masood I, Hassan U, Ijaz B, Hanif F, Syed AA, Yusuf MA, Rashid MU. Contribution of germline PALB2 variants to an unselected and prospectively registered pancreatic cancer patient cohort in Pakistan. HPB (Oxford) 2022; 24:2134-2144. [PMID: 36175305 DOI: 10.1016/j.hpb.2022.09.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 09/02/2022] [Accepted: 09/12/2022] [Indexed: 01/24/2023]
Abstract
BACKGROUND Partner and localizer of BRCA2 (PALB2) is a pancreatic cancer (PC) susceptibility gene reported in Caucasians. However, limited data are available among Asians. We investigated the contribution of PALB2 germline variants to Pakistani PC patients. METHODS 150 unselected and prospectively enrolled PC patients were comprehensively screened for PALB2 variants, using denaturing high-performance liquid chromatography and DNA sequencing. Novel variants were investigated for their pathogenic effect using in-silico tools. Potentially functional variants were screened in 200 controls. RESULTS Twenty-two different PALB2 variants were identified. A missense variant (p.Arg37His) was identified in a 48-years-old male patient with a family history of breast cancer. Another missense variant (p.Trp898Arg) was identified in a 48-years-old male patient with a family history of esophageal cancer. A novel 3' downstream variant (c.∗480A>G) was detected in a 34-years-old female patient with family history of lung cancer. Another novel 3' downstream variant (c.∗417A>C) was identified in a 41-years-old male patient. All these variants were absent in 200 controls. p.Arg37His and p.Trp898Arg were predicted as likely pathogenic. c.∗417A>C and c.∗480A>G were classified as variants of uncertain significance. CONCLUSION This is the first study that suggests a minimal contribution of PALB2 variants to PC risk in Pakistani population.
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Affiliation(s)
- Noor Muhammad
- Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Center (SKMCH&RC), Lahore, Pakistan
| | - Rida Sadaqat
- Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Center (SKMCH&RC), Lahore, Pakistan
| | - Humaira Naeemi
- Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Center (SKMCH&RC), Lahore, Pakistan
| | - Iqra Masood
- Clinical Research Office, SKMCH&RC, Lahore, Pakistan
| | - Usman Hassan
- Department of Pathology, SKMCH&RC, Lahore, Pakistan
| | - Bushra Ijaz
- Laboratory of Applied and Functional Genomics, National Center of Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan
| | - Faisal Hanif
- Department of Surgical Oncology, SKMCH&RC, Lahore, Pakistan; Centre for Liver and Biliary Sciences, Bahria International Hospital, Lahore, Pakistan
| | - Aamir A Syed
- Department of Surgical Oncology, SKMCH&RC, Lahore, Pakistan
| | | | - Muhammad U Rashid
- Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Center (SKMCH&RC), Lahore, Pakistan.
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Akbar F, Siddiqui Z, Waheed MT, Ehsan L, Ali SI, Wiquar H, Valimohammed AT, Khan S, Vohra L, Zeeshan S, Rashid Y, Moosajee M, Jabbar AA, Zahir MN, Zahid N, Soomro R, Ullah NN, Ahmad I, Haider G, Ansari U, Rizvi A, Mehboobali A, Sattar A, Kirmani S. Spectrum of germline pathogenic variants using a targeted next generation sequencing panel and genotype-phenotype correlations in patients with suspected hereditary breast cancer at an academic medical centre in Pakistan. Hered Cancer Clin Pract 2022; 20:24. [PMID: 35710434 PMCID: PMC9204946 DOI: 10.1186/s13053-022-00232-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Accepted: 05/30/2022] [Indexed: 11/30/2022] Open
Abstract
Background Breast cancer is the most common malignancy in women, affecting over 1.5 million women every year, which accounts for the highest number of cancer-related deaths in women globally. Hereditary breast cancer (HBC), an important subset of breast cancer, accounts for 5–10% of total cases. However, in Low Middle-Income Countries (LMICs), the population-specific risk of HBC in different ethnicities and the correlation with certain clinical characteristics remain unexplored. Methods Retrospective chart review of patients who visited the HBC clinic and proceeded with multi-gene panel testing from May 2017 to April 2020. Descriptive and inferential statistics were used to analyze clinical characteristics of patients. Fisher’s exact, Pearson’s chi-squared tests and Logistic regression analysis were used for categorical variables and Wilcoxon rank-sum test were used for quantitative variables. For comparison between two independent groups, Mann-Whitney test was performed. Results were considered significant at a p value of < 0.05. Results Out of 273 patients, 22% tested positive, 37% had a VUS and 41% had a negative genetic test result. Fifty-five percent of the positive patients had pathogenic variants in either BRCA1 or BRCA2, while the remaining positive results were attributed to other genes. Patients with a positive result had a younger age at diagnosis compared to those having a VUS and a negative result; median age 37.5 years, IQR (Interquartile range) (31.5–48). Additionally, patients with triple negative breast cancer (TNBC) were almost 3 times more likely to have a positive result (OR = 2.79, CI = 1.42–5.48 p = 0.003). Of all patients with positive results, 25% of patients had a negative family history of breast and/or related cancers. Conclusions In our HBC clinic, we observed that our rate of positive results is comparable, yet at the higher end of the range which is reported in other populations. The importance of expanded, multi-gene panel testing is highlighted by the fact that almost half of the patients had pathogenic or likely pathogenic variants in genes other than BRCA1/2, and that our test positivity rate would have only been 12.8% if only BRCA1/2 testing was done. As the database expands and protocol-driven referrals are made across the country, our insight about the genetic architecture of HBC in our population will continue to increase. Supplementary Information The online version contains supplementary material available at 10.1186/s13053-022-00232-2.
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Affiliation(s)
- Fizza Akbar
- Division of Women and Child Health, Aga Khan University, Karachi, Pakistan
| | | | | | - Lubaina Ehsan
- Medical College, Aga Khan University, Karachi, Pakistan.,School of Medicine, Western Michigan University Stryker, Kalamazoo, MI, USA
| | - Syed Ibaad Ali
- School of Medicine, Western Michigan University Stryker, Kalamazoo, MI, USA
| | - Hajra Wiquar
- Division of Women and Child Health, Aga Khan University, Karachi, Pakistan
| | | | - Shaista Khan
- Department of Surgery, Aga Khan University, Karachi, Pakistan
| | - Lubna Vohra
- Department of Surgery, Aga Khan University, Karachi, Pakistan
| | - Sana Zeeshan
- Department of Surgery, Aga Khan University, Karachi, Pakistan
| | - Yasmin Rashid
- Department of Oncology, Aga Khan University, Karachi, Pakistan
| | - Munira Moosajee
- Department of Oncology, Aga Khan University, Karachi, Pakistan
| | | | | | - Naila Zahid
- Liaquat National Hospital and Medical College, Karachi, Pakistan
| | - Rufina Soomro
- Liaquat National Hospital and Medical College, Karachi, Pakistan
| | | | - Imran Ahmad
- Cancer Foundation Hospital, Karachi, Pakistan
| | | | - Uzair Ansari
- Department of Pediatrics and Child Health, Aga Khan University, Karachi, Pakistan
| | - Arjumand Rizvi
- Department of Pediatrics and Child Health, Aga Khan University, Karachi, Pakistan
| | - Arif Mehboobali
- Division of Women and Child Health, Aga Khan University, Karachi, Pakistan
| | - Abida Sattar
- Department of Surgery, Aga Khan University, Karachi, Pakistan
| | - Salman Kirmani
- Division of Women and Child Health, Aga Khan University, Karachi, Pakistan.
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Siraj AK, Masoodi T, Bu R, Parvathareddy SK, Iqbal K, Azam S, Al-Rasheed M, Ajarim D, Tulbah A, Al-Dayel F, Al-Kuraya KS. Prevalence of germline TP53 mutation among early onset middle eastern breast cancer patients. Hered Cancer Clin Pract 2021; 19:49. [PMID: 34906214 PMCID: PMC8670057 DOI: 10.1186/s13053-021-00206-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Accepted: 11/29/2021] [Indexed: 11/22/2022] Open
Abstract
Background The data on prevalence and clinical relevance of TP53 germline mutations in early onset Middle-Eastern breast cancer (BC) is limited. Methods We determined TP53 germline mutations in a cohort of 464 early onset BC patients from Saudi Arabia using capture sequencing based next generation sequencing. Results Germline TP53 pathogenic mutations were found in 1.5% (7/464) of early onset Saudi BC patients. A total of six pathogenic missense mutations, one stop gain mutation and two variants of uncertain significance (VUS) were detected in our cohort. No TP53 pathogenic mutations were detected among 463 healthy controls. TP53 mutations carriers were significantly more likely to have bilateral breast cancer (p = 0.0008). At median follow-up of 41 months, TP53 mutations were an unfavorable factor for overall survival in univariate analysis. All the patients carrying TP53 mutations were negative for BRCA1 and BRCA2 mutations. Majority of patients (85.7%; 6/7) carrying TP53 mutation had no family history suggestive of Li-Fraumeni Syndrome (LFS) or personal history of multiple LFS related tumors. Only one patient had a positive family history suggestive of LFS. Conclusions TP53 germline mutation screening detects a clinically meaningful risk of early onset BC from this ethnicity and should be considered in all early onset BC regardless of the family history of cancer, especially in young patients that are negative for BRCA mutations. Supplementary Information The online version contains supplementary material available at 10.1186/s13053-021-00206-w.
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Affiliation(s)
- Abdul Khalid Siraj
- Human Cancer Genomic Research, King Faisal Specialist Hospital and Research Center, P.O. Box 3354, 11211, Riyadh, Saudi Arabia
| | - Tariq Masoodi
- Human Cancer Genomic Research, King Faisal Specialist Hospital and Research Center, P.O. Box 3354, 11211, Riyadh, Saudi Arabia
| | - Rong Bu
- Human Cancer Genomic Research, King Faisal Specialist Hospital and Research Center, P.O. Box 3354, 11211, Riyadh, Saudi Arabia
| | - Sandeep Kumar Parvathareddy
- Human Cancer Genomic Research, King Faisal Specialist Hospital and Research Center, P.O. Box 3354, 11211, Riyadh, Saudi Arabia
| | - Kaleem Iqbal
- Human Cancer Genomic Research, King Faisal Specialist Hospital and Research Center, P.O. Box 3354, 11211, Riyadh, Saudi Arabia
| | - Saud Azam
- Human Cancer Genomic Research, King Faisal Specialist Hospital and Research Center, P.O. Box 3354, 11211, Riyadh, Saudi Arabia
| | - Maha Al-Rasheed
- Human Cancer Genomic Research, King Faisal Specialist Hospital and Research Center, P.O. Box 3354, 11211, Riyadh, Saudi Arabia
| | - Dahish Ajarim
- Department of Oncology, King Faisal Specialist Hospital and Research Centre, P.O. Box 3354, 11211, Riyadh, Saudi Arabia
| | - Asma Tulbah
- Department of Pathology, King Faisal Specialist Hospital and Research Centre, P.O. Box 3354, 11211, Riyadh, Saudi Arabia
| | - Fouad Al-Dayel
- Department of Pathology, King Faisal Specialist Hospital and Research Centre, P.O. Box 3354, 11211, Riyadh, Saudi Arabia
| | - Khawla Sami Al-Kuraya
- Human Cancer Genomic Research, King Faisal Specialist Hospital and Research Center, P.O. Box 3354, 11211, Riyadh, Saudi Arabia. .,Research Center, Human Cancer Genomic Research, King Faisal Specialist Hospital and Research Center, MBC#98-16, P.O. Box 3354, 11211, Riyadh, Saudi Arabia.
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Arshad S, Ishaque I, Mumtaz S, Rashid MU, Malkani N. In-Silico Analyses of Nonsynonymous Variants in the BRCA1 Gene. Biochem Genet 2021; 59:1506-1526. [PMID: 33945048 DOI: 10.1007/s10528-021-10074-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 04/22/2021] [Indexed: 10/21/2022]
Abstract
BReast CAncer gene 1 (BRCA1)-a tumor suppressor gene plays an important role in the DNA repair mechanism. Several BRCA1 variants perturb its structure and function, including synonymous and nonsynonymous single nucleotide polymorphisms (SNPs). In the present study, we performed in-silico analyses of nonsynonymous SNPs (nsSNPs) of the BRCA1 gene. In total, 122 nsSNPs were retrieved from the NCBI SNP database and in-silico analyses were performed using computational prediction tools: SIFT, PROVEAN, Mutation Taster, PolyPhen-2, MutPred, and ConSurf. Of these tools, SIFT, PROVEAN, and Mutation Taster predicted 61 out of 122 nsSNPs as "damaging", based on structural homology analysis. PolyPhen-2 classified 22 nsSNPs as "probably damaging". These nsSNPs were further analyzed by MutPred to predict basic molecular mechanisms of amino acid alteration. ConSurf analysis predicted eleven conserved amino acid residues with structural and functional consequences. We identified five amino acid residues in the RING finger domain (L22, C39, H41, C44, and C47) and two in the BRCT domain (P1771 and I1707) with the potential to deter the BRCA1 protein function. This study provides insights into the effect of nsSNPs and amino acid substitutions in BRCA1.
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Affiliation(s)
- Sidra Arshad
- Department of Zoology, GC University, Lahore, Pakistan
| | - Irfan Ishaque
- Department of Zoology, GC University, Lahore, Pakistan
| | - Sidra Mumtaz
- Department of Zoology, GC University, Lahore, Pakistan
| | - Muhammad Usman Rashid
- Department of Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH&RC), Lahore, Pakistan
| | - Naila Malkani
- Department of Zoology, GC University, Lahore, Pakistan.
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Rashid MU, Muhammad N, Khan FA, Shehzad U, Naeemi H, Malkani N, Hamann U. Prevalence of RECQL germline variants in Pakistani early-onset and familial breast cancer patients. Hered Cancer Clin Pract 2020; 18:25. [PMID: 33342430 PMCID: PMC7749988 DOI: 10.1186/s13053-020-00159-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 12/11/2020] [Indexed: 12/24/2022] Open
Abstract
Background The RecQ Like Helicase (RECQL) gene has previously been shown to predispose to breast cancer mainly in European populations, in particular to estrogen receptor (ER) and/or progesterone receptor (PR) positive tumor. Here, we investigated the contribution of pathogenic RECQL germline variants to hereditary breast cancer in early-onset and familial breast cancer patients from Pakistan. Methods Comprehensive RECQL variant analysis was performed in 302 BRCA1 and BRCA2 negative patients with ER and/or PR positive breast tumors using denaturing high-performance liquid chromatography followed by DNA sequencing. Novel variants were classified using Sherloc guidelines. Results One novel pathogenic protein-truncating variant (p.W75*) was identified in a 37-year-old familial breast cancer patient. The pathogenic variant frequencies were 0.3% (1/302) in early-onset and familial breast cancer patients and 0.8% (1/133) in familial patients. Further, three novel variants of unknown significance, p.I141F, p.S182S, and p.C475C, were identified in familial breast cancer patients at the age of 47, 68, and 47 respectively. All variants were absent in 250 controls. Conclusions Our data suggest that the RECQL gene plays a negligible role in breast cancer predisposition in Pakistan.
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Affiliation(s)
- Muhammad Usman Rashid
- Department of Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH&RC), 7A, Block R3, Johar Town, Lahore, Punjab, 54000, Pakistan. .,Molecular Genetics of Breast Cancer, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 580, 69120, Heidelberg, Germany.
| | - Noor Muhammad
- Department of Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH&RC), 7A, Block R3, Johar Town, Lahore, Punjab, 54000, Pakistan
| | - Faiz Ali Khan
- Department of Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH&RC), 7A, Block R3, Johar Town, Lahore, Punjab, 54000, Pakistan
| | - Umara Shehzad
- Department of Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH&RC), 7A, Block R3, Johar Town, Lahore, Punjab, 54000, Pakistan
| | - Humaira Naeemi
- Department of Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH&RC), 7A, Block R3, Johar Town, Lahore, Punjab, 54000, Pakistan
| | - Naila Malkani
- Department of Zoology, Government College University, Lahore, Pakistan
| | - Ute Hamann
- Molecular Genetics of Breast Cancer, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 580, 69120, Heidelberg, Germany.
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Rogoża-Janiszewska E, Malińska K, Górski B, Scott RJ, Cybulski C, Kluźniak W, Lener M, Jakubowska A, Gronwald J, Huzarski T, Lubiński J, Dębniak T. Prevalence of germline TP53 variants among early-onset breast cancer patients from Polish population. Breast Cancer 2020; 28:226-235. [PMID: 32888145 PMCID: PMC7796867 DOI: 10.1007/s12282-020-01151-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Accepted: 08/20/2020] [Indexed: 11/28/2022]
Abstract
Background The objective of this study was to determine spectrum and prevalence of germline mutations in TP53 gene among Polish women with early-onset breast cancer (BC), which has not been determined until now. Methods A cohort of 100 females with BC diagnosed ≤ 30 years of age and with a positive family history of cancer was used as a discovery cohort. 1880 women with BC ≤ 45 years old and a control group of 2000 healthy women were genotyped as a replication phase of this study. Results Four heterozygous pathogenic missense mutations were detected in a group of 100 patients with early-onset breast cancer. On the basis of software prediction and available literature data, all these variants were defined as pathogenic. None of these TP53 variants were detected among 1880 breast cancer patients and 2000 healthy controls. No large mutations were found among early-onset cases using MLPA reaction. Conclusion Germline pathogenic TP53 variants were found in 4% early-onset Polish BC patients. No founder mutations were identified in Polish population. To improve the treatment and surveillance screening, the search for germline TP53 pathogenic variants is recommended for all female BC cases diagnosed ≤ 30 years old. Electronic supplementary material The online version of this article (10.1007/s12282-020-01151-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Emilia Rogoża-Janiszewska
- Department of Genetics and Pathology, International Hereditary Cancer Center, Pomeranian Medical University, Szczecin, Poland.
| | - Karolina Malińska
- Department of Genetics and Pathology, International Hereditary Cancer Center, Pomeranian Medical University, Szczecin, Poland
| | - Bohdan Górski
- Department of Genetics and Pathology, International Hereditary Cancer Center, Pomeranian Medical University, Szczecin, Poland
| | - Rodney J Scott
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, NSW, Australia.,Department of Molecular Medicine, NSW Health Pathology-Hunter, Newcastle, NSW, Australia
| | - Cezary Cybulski
- Department of Genetics and Pathology, International Hereditary Cancer Center, Pomeranian Medical University, Szczecin, Poland
| | - Wojciech Kluźniak
- Department of Genetics and Pathology, International Hereditary Cancer Center, Pomeranian Medical University, Szczecin, Poland
| | - Marcin Lener
- Department of Genetics and Pathology, International Hereditary Cancer Center, Pomeranian Medical University, Szczecin, Poland
| | - Anna Jakubowska
- Department of Genetics and Pathology, International Hereditary Cancer Center, Pomeranian Medical University, Szczecin, Poland
| | - Jacek Gronwald
- Department of Genetics and Pathology, International Hereditary Cancer Center, Pomeranian Medical University, Szczecin, Poland
| | - Tomasz Huzarski
- Department of Genetics and Pathology, International Hereditary Cancer Center, Pomeranian Medical University, Szczecin, Poland
| | - Jan Lubiński
- Department of Genetics and Pathology, International Hereditary Cancer Center, Pomeranian Medical University, Szczecin, Poland
| | - Tadeusz Dębniak
- Department of Genetics and Pathology, International Hereditary Cancer Center, Pomeranian Medical University, Szczecin, Poland
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Rashid MU, Khan FA, Muhammad N, Loya A, Hamann U. Prevalence of PALB2 Germline Mutations in Early-onset and Familial Breast/Ovarian Cancer Patients from Pakistan. Cancer Res Treat 2019; 51:992-1000. [PMID: 30309218 PMCID: PMC6639217 DOI: 10.4143/crt.2018.356] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 10/10/2018] [Indexed: 01/02/2023] Open
Abstract
PURPOSE Partner and localizer of BRCA2 (PALB2) is a breast cancer susceptibility gene that plays an important role in DNA repair. This is the first study assessing the prevalence of PALB2 mutations in early-onset and familial breast/ovarian cancer patients from Pakistan. MATERIALS AND METHODS PALB2 mutation screening was performed in 370 Pakistani patients with early-onset and familial breast/ovarian cancer, who were negative for BRCA1, BRCA2, TP53, CHEK2, and RAD51C mutations, using denaturing high-performance liquid chromatography analysis. Mutations were confirmed by DNA sequencing. Novel PALB2 alterations were analyzed for their potential effect on protein function or splicing using various in silico prediction tools. Three-hundred and seventy-two healthy controls were screened for the presence of the identified (potentially) functional mutations. RESULTS A novel nonsense mutation, p.Y743*, was identified in one familial breast cancer patient (1/127, 0.8%). Besides, four in silico-predicted potentially functional mutations including three missense mutations and one 5' untranslated region mutation were identified: p.D498Y, novel p.G644R, novel p.E744K, and novel c.-134_-133delTCinsGGGT. The mutations p.Y743* and p.D498Y were identified in two familial patients diagnosed with unilateral or synchronous bilateral breast cancer at the ages of 29 and 39, respectively. The other mutations were identified in an early-onset (≤ 30 years of age) breast cancer patient each. All five mutations were absent in 372 healthy controls suggesting that they are disease associated. CONCLUSION Our findings show that PALB2 mutations account for a small proportion of early-onset and hereditary breast/ovarian cancer cases in Pakistan.
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Affiliation(s)
- Muhammad Usman Rashid
- Department of Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH&RC), Lahore, Pakistan
- Molecular Genetics of Breast Cancer, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Faiz Ali Khan
- Department of Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH&RC), Lahore, Pakistan
| | - Noor Muhammad
- Department of Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH&RC), Lahore, Pakistan
| | - Asif Loya
- Department of Pathology, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH&RC), Lahore, Pakistan
| | - Ute Hamann
- Molecular Genetics of Breast Cancer, German Cancer Research Center (DKFZ), Heidelberg, Germany
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Fortuno C, James PA, Spurdle AB. Current review of TP53 pathogenic germline variants in breast cancer patients outside Li-Fraumeni syndrome. Hum Mutat 2018; 39:1764-1773. [PMID: 30240537 DOI: 10.1002/humu.23656] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 08/31/2018] [Accepted: 09/19/2018] [Indexed: 12/16/2022]
Abstract
Pathogenic germline variants in TP53 predispose carriers to the multi-cancer Li-Fraumeni syndrome (LFS). Widespread multigene panel testing is identifying TP53 pathogenic variants in breast cancer patients outside the strict clinical criteria recommended for LFS testing. We aimed to assess frequency and clinical implications of TP53 pathogenic variants in breast cancer cohorts ascertained outside LFS. Classification of TP53 germline variants reported in 59 breast cancer studies, and publicly available population control sets was reviewed and identified evidence for misclassification of variants. TP53 pathogenic variant frequency was determined for: breast cancer studies grouped by ascertainment characteristics; breast cancer cohorts undergoing panel testing; and population controls. Early age of breast cancer onset, regardless of family history or BRCA1/BRCA2 previous testing, had the highest pick-up rate for TP53 carriers. Patients at risk of hereditary breast cancer unselected for features of LFS carried TP53 pathogenic variants at a frequency comparable to that of other non-BRCA1/2 breast cancer predisposing genes, and ∼threefold more than reported in population controls. These results have implications for the implementation of TP53 testing in broader clinical settings, and suggest urgent need to investigate cancer risks associated with TP53 pathogenic variants in individuals outside the LFS spectrum.
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Affiliation(s)
- Cristina Fortuno
- QIMR Berghofer Medical Research Institute, Herston, Brisbane, Australia
| | - Paul A James
- Peter MacCallum Cancer Centre and Royal Melbourne Hospital Familial Cancer Centre, Melbourne, Australia
| | - Amanda B Spurdle
- QIMR Berghofer Medical Research Institute, Herston, Brisbane, Australia
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Rashid MU, Muhammad N, Bajwa S, Faisal S, Tahseen M, Bermejo JL, Amin A, Loya A, Hamann U. High prevalence and predominance of BRCA1 germline mutations in Pakistani triple-negative breast cancer patients. BMC Cancer 2016; 16:673. [PMID: 27553291 PMCID: PMC4995655 DOI: 10.1186/s12885-016-2698-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 08/09/2016] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Women harboring BRCA1/2 germline mutations have high lifetime risk of developing breast/ovarian cancer. The recommendation to pursue BRCA1/2 testing is based on patient's family history of breast/ovarian cancer, age of disease-onset and/or pathologic parameters of breast tumors. Here, we investigated if diagnosis of triple-negative breast cancer (TNBC) independently increases risk of carrying a BRCA1/2 mutation in Pakistan. METHODS Five hundred and twenty-three breast cancer patients including 237 diagnosed ≤ 30 years of age and 286 with a family history of breast/ovarian cancer were screened for BRCA1/2 small-range mutations and large genomic rearrangements. Immunohistochemical analyses were performed at one center. Univariate and multiple logistic regression models were used to investigate possible differences in prevalence of BRCA1/2 mutations according to patient and tumor characteristics. RESULTS Thirty-seven percent of patients presented with TNBC. The prevalence of BRCA1 mutations was higher in patients with TNBC than non-TNBC (37 % vs. 10 %, P < 0.0001). 1 % of TNBC patients were observed to have BRCA2 mutations. Subgroup analyses revealed a larger proportion of BRCA1 mutations in TNBC than non-TNBC among patients 1) diagnosed at early-age with no family history of breast/ovarian cancer (14 % vs. 5 %, P = 0.03), 2) diagnosed at early-age irrespective of family history (28 % vs. 11 %, P = 0.0003), 3) had a family history of breast cancer (49 % vs. 12 %, P < 0.0001), and 4) those with family history of breast and ovarian cancer (81 % vs. 28 %, P = 0.0005). TNBC patients harboring BRCA1 mutations were diagnosed at a later age than non-carriers (median age at diagnosis: 30 years (range 22-53) vs. 28 years (range 18-67), P = 0.002). The association between TNBC status and presence of BRCA1 mutations was independent of the simultaneous consideration of family phenotype, tumor histology and grade in a multiple logistic regression model (Ratio of the probability of carrying BRCA1/2 mutations for TNBC vs. non-TNBC 4.23; 95 % CI 2.50-7.14; P < 0.0001). CONCLUSION Genetic BRCA1 testing should be considered for Pakistani women diagnosed with TNBC.
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Affiliation(s)
- Muhammad Usman Rashid
- Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH & RC), Lahore, Pakistan.,German Cancer Research Center (DKFZ), Molecular Genetics of Breast Cancer, Heidelberg, Germany
| | - Noor Muhammad
- Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH & RC), Lahore, Pakistan
| | - Seerat Bajwa
- Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH & RC), Lahore, Pakistan
| | - Saima Faisal
- Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH & RC), Lahore, Pakistan
| | - Muhammad Tahseen
- Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH & RC), Lahore, Pakistan
| | - Justo Lorenzo Bermejo
- Institute of Medical Biometry and Informatics, University of Heidelberg, Heidelberg, Germany
| | - Asim Amin
- Levine Cancer Institute (LCI), Charlotte, USA
| | - Asif Loya
- Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH & RC), Lahore, Pakistan
| | - Ute Hamann
- German Cancer Research Center (DKFZ), Molecular Genetics of Breast Cancer, Heidelberg, Germany.
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Ng PS, Wen WX, Fadlullah MZH, Yoon SY, Lee SY, Thong MK, Yip CH, Mohd Taib NA, Teo SH. Identification of germline alterations in breast cancer predisposition genes among Malaysian breast cancer patients using panel testing. Clin Genet 2016; 90:315-23. [PMID: 26757417 DOI: 10.1111/cge.12735] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 01/07/2016] [Accepted: 01/08/2016] [Indexed: 12/23/2022]
Abstract
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.
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Affiliation(s)
- P S Ng
- Cancer Research Malaysia, Subang Jaya, Selangor, Malaysia.,University Malaya Cancer Research Institute, Faculty of Medicine, University Malaya, Kuala Lumpur, Malaysia
| | - W X Wen
- Cancer Research Malaysia, Subang Jaya, Selangor, Malaysia.,University Malaya Cancer Research Institute, Faculty of Medicine, University Malaya, Kuala Lumpur, Malaysia
| | | | - S Y Yoon
- Cancer Research Malaysia, Subang Jaya, Selangor, Malaysia
| | - S Y Lee
- Cancer Research Malaysia, Subang Jaya, Selangor, Malaysia
| | - M K Thong
- Department of Paediatrics, Faculty of Medicine, University Malaya, Kuala Lumpur, Malaysia
| | - C H Yip
- Subang Jaya Medical Centre, Subang Jaya, Selangor, Malaysia
| | - N A Mohd Taib
- University Malaya Cancer Research Institute, Faculty of Medicine, University Malaya, Kuala Lumpur, Malaysia.,Department of Surgery, Faculty of Medicine, University Malaya Medical Centre, Kuala Lumpur, Malaysia
| | - S H Teo
- Cancer Research Malaysia, Subang Jaya, Selangor, Malaysia. .,University Malaya Cancer Research Institute, Faculty of Medicine, University Malaya, Kuala Lumpur, Malaysia. .,Department of Surgery, Faculty of Medicine, University Malaya Medical Centre, Kuala Lumpur, Malaysia.
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Abstract
Breast cancer is a global health issue, and as the tumor burden increases, we need to come up with newer, better technologies which are convenient, cheap, rapid, sensitive with a high specificity. Technological advancements in the field of cancer biomarker has led to the development of techniques such as mass spectrometric analysis and microarray analysis in which genes, proteins and hundreds and thousands of metabolites can be identified with the emergence of genomics, proteomics and metabolomics. This research is focused on finding biomarkers for diagnosis, prognosis, staging, treatment response and targets for chemotherapy, generating a panel of markers which provide better clinical information compared to a single marker in the panel. This review briefly summarizes application of genomics and proteomics followed by key concepts and applications of metabolomics in breast cancer, with the conclusion that an integration of the three “OMIC” technologies may hold the key to future biomarker discovery.
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Affiliation(s)
- Naila Irum Hadi
- Dr. Naila Irum Hadi, MBBS, MPhil, PhD fellow. Professor of Pathology, Ziauddin University, Karachi, Pakistan
| | - Qamar Jamal
- Dr. Qamar Jamal, MBBS, MPhil, PhD. Professor of Pathology, Ziauddin University, Karachi, Pakistan
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Rashid MU, Muzaffar M, Khan FA, Kabisch M, Muhammad N, Faiz S, Loya A, Hamann U. Association between the BsmI Polymorphism in the Vitamin D Receptor Gene and Breast Cancer Risk: Results from a Pakistani Case-Control Study. PLoS One 2015; 10:e0141562. [PMID: 26517870 PMCID: PMC4627649 DOI: 10.1371/journal.pone.0141562] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Accepted: 10/10/2015] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND Vitamin D is postulated to decrease the risk of breast cancer by inhibiting cell proliferation via the vitamin D receptor (VDR). Two common single nucleotide polymorphisms (SNPs) in the VDR gene, rs1544410 (BsmI) and rs2228570 (FokI), are inconsistently associated with breast cancer risk in Caucasian populations, while data for Asians are scarce. Here, we investigated the possible contribution of these SNPs to breast cancer risk in Pakistani breast cancer patients and in controls participating in a hospital-based breast cancer case-control study (PAK-BCCC). METHODS Genotyping of the BsmI and FokI SNPs was performed by PCR-based restriction fragment length polymorphism (RFLP) analysis of 463 genetically enriched female breast cancer cases with known BRCA1/2 status and in 1,012 controls from Pakistan. The association between SNP genotypes and breast cancer risk was investigated by logistic regression adjusted for potential breast cancer risk factors and stratified by BRCA1/2 status and family history. Odds ratios (ORs) and 95% confidence intervals (CIs) were reported. RESULTS The b allele of the BsmI was associated with an increased breast cancer risk (per b allele OR 1.28, 95% CI 1.09-1.49, P = 0.003). Subgroup analysis revealed that this effect was restricted to BRCA1/2 non-carriers (per b allele OR 1.33, 95% CI 1.11-1.59, P = 0.002) and was stronger in those who reported a positive family history of breast and/or ovarian cancer (per b allele OR 1.64, 95% CI 1.20-2.22, P = 0.002). No association with breast cancer risk was detected for the FokI SNP. CONCLUSIONS The BsmI polymorphism in the VDR gene may be associated with an increased breast cancer risk in Pakistani women negative for BRCA1/2 germline mutations.
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Affiliation(s)
- Muhammad Usman Rashid
- Department of Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH & RC), Lahore, Pakistan
- Department of Human Genetics and Molecular Biology, University of Health Sciences, Lahore, Pakistan
- Molecular Genetics of Breast Cancer, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Merium Muzaffar
- Department of Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH & RC), Lahore, Pakistan
- Department of Physiology, University of Health Sciences, Lahore, Pakistan
| | - Faiz Ali Khan
- Department of Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH & RC), Lahore, Pakistan
| | - Maria Kabisch
- Molecular Genetics of Breast Cancer, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Noor Muhammad
- Department of Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH & RC), Lahore, Pakistan
| | - Sabeen Faiz
- Department of Basic Sciences Research, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH & RC), Lahore, Pakistan
| | - Asif Loya
- Department of Pathology, Shaukat Khanum Memorial Cancer Hospital and Research Centre (SKMCH & RC), Lahore, Pakistan
| | - Ute Hamann
- Molecular Genetics of Breast Cancer, German Cancer Research Center (DKFZ), Heidelberg, Germany
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Rashid MU, Muhammad N, Faisal S, Amin A, Hamann U. Deleterious RAD51C germline mutations rarely predispose to breast and ovarian cancer in Pakistan. Breast Cancer Res Treat 2014; 145:775-84. [DOI: 10.1007/s10549-014-2972-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Accepted: 04/15/2014] [Indexed: 12/17/2022]
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Rashid MU, Muhammad N, Faisal S, Amin A, Hamann U. Constitutional CHEK2 mutations are infrequent in early-onset and familial breast/ovarian cancer patients from Pakistan. BMC Cancer 2013; 13:312. [PMID: 23806170 PMCID: PMC3699428 DOI: 10.1186/1471-2407-13-312] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Accepted: 05/22/2013] [Indexed: 01/28/2023] Open
Abstract
Background Less than 20% of Pakistani women with early-onset or familial breast/ovarian cancer harbor germ line mutations in the high-penetrance genes BRCA1, BRCA2 and TP53. Thus, mutations in other genes confer genetic susceptibility to breast cancer, of which CHEK2 is a plausible candidate. CHEK2 encodes a checkpoint kinase, involved in response to DNA damage. Methods In the present study we assessed the prevalence of CHEK2 germ line mutations in 145 BRCA1/2-negative early-onset and familial breast/ovarian cancer patients from Pakistan (Group 1). Mutation analysis of the complete CHEK2 coding region was performed using denaturing high-performance liquid chromatography analysis, followed by DNA sequencing of variant fragments. Results Two potentially deleterious missense mutations, c.275C>G (p.P92R) and c.1216C>T, (p.R406C), were identified (1.4%). The c.275C>G mutation is novel and has not been described in other populations. It was detected in a 30-year-old breast cancer patient with a family history of breast and multiple other cancers. The c.1216C>T mutation was found in a 34-year-old ovarian cancer patient from a family with two breast cancer cases. Both mutations were not detected in 229 recently recruited BRCA1/2-negative high risk patients (Group 2). Conclusion Our findings suggest that CHEK2 mutations may not contribute significantly to breast/ovarian cancer risk in Pakistani women.
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Affiliation(s)
- Muhammad U Rashid
- Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore, Pakistan.
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