- Open Access
- Open Peer Review
Molecular genetics analysis of hereditary breast and ovarian cancer patients in India
- Nagasamy Soumittra†1, 2,
- Balaiah Meenakumari1,
- Tithi Parija1,
- Veluswami Sridevi3,
- Karunakaran N Nancy1,
- Rajaraman Swaminathan4,
- Kamalalayam R Rajalekshmy5,
- Urmila Majhi6 and
- Thangarajan Rajkumar1Email author
© Soumittra et al; licensee BioMed Central Ltd. 2009
- Received: 12 May 2009
- Accepted: 6 August 2009
- Published: 6 August 2009
Hereditary cancers account for 5–10% of cancers. In this study BRCA1, BRCA2 and CHEK2*(1100delC) were analyzed for mutations in 91 HBOC/HBC/HOC families and early onset breast and early onset ovarian cancer cases.
PCR-DHPLC was used for mutation screening followed by DNA sequencing for identification and confirmation of mutations. Kaplan-Meier survival probabilities were computed for five-year survival data on Breast and Ovarian cancer cases separately, and differences were tested using the Log-rank test.
Fifteen (16%) pathogenic mutations (12 in BRCA1 and 3 in BRCA2), of which six were novel BRCA1 mutations were identified. None of the cases showed CHEK2*1100delC mutation. Many reported polymorphisms in the exonic and intronic regions of BRCA1 and BRCA2 were also seen. The mutation status and the polymorphisms were analyzed for association with the clinico-pathological features like age, stage, grade, histology, disease status, survival (overall and disease free) and with prognostic molecular markers (ER, PR, c-erbB2 and p53).
The stage of the disease at diagnosis was the only statistically significant (p < 0.0035) prognostic parameter. The mutation frequency and the polymorphisms were similar to reports on other ethnic populations. The lack of association between the clinico-pathological variables, mutation status and the disease status is likely to be due to the small numbers.
- Breast Cancer
- Ovarian Cancer
- Breast Cancer Case
- BRCA2 Gene
- Missense Variation
Breast cancer is the most common cancer among women in Chennai with the crude incidence rate (CIR) being 30.1/100,000 in the Madras Metropolitan Tumor Registry (MMTR). A significant increasing trend in the incidence of breast cancer was seen during 1982–2005 with an average annual increase of 0.72 per 100,000 . The trend of rising incidence rate is likely to continue due to further changes in life style factors such as age of first child birth and dietary habits .
BRCA1 and BRCA2 genes had been identified by linkage analysis and positional cloning on large breast cancer families in the early 1990's [3, 4]. This has improved the understanding of the molecular genetics of the hereditary breast and ovarian cancer thus providing scope for better management in these patients and in offering predictive testing, aggressive screening and preventive strategies to the unaffected carriers in the same family. The CHEK2*1100delC mutation confers a low risk of breast cancer in non-BRCA1/BRCA2 mutation carriers . The average cumulative risk of breast cancer in a BRCA1 and BRCA2 mutation carrier is 65% and 45% by the age of 70 years, respectively. For ovarian cancer the risk is 39% and 11%, in BRCA1 and BRCA2 mutation carriers by 70 years, respectively . Slightly elevated risk of colon and prostate cancer in BRCA1 mutation carriers and increased risk of other malignancies including pancreatic, stomach and head and neck cancers and a large increase in the relative risk for male breast cancer is seen in BRCA2 mutation carriers [7, 8].
Other genes like TP53, ATM, SKT11, PTEN, PTCH MLH1, MSH2, PMS1, PMS2, MSH6 have been associated with increased risk of breast and ovarian cancer as part of other cancer syndromes . Recently genome wide association study identified four plausible causative genes namely FGFR2, TNRC9, MAP3K1 and LSP1 that confer moderate susceptibility to breast cancer .
Generally, hereditary breast cancers are earlier in onset and have a higher prevalence of bilateral breast cancers. Breast tumors from BRCA1- carriers are more likely to be highly proliferative; poorly differentiated (grade III); more likely to have a medullary or atypical medullary-like appearance with high degree of lymphocyte infiltration; and show excess of continuous pushing margins . Moreover these tumors are more often ER, PR and c-erbB2 negative and frequently show p53 alterations . Lakhani and Bell et al report BRCA2 tumors to be of higher grade than the sporadic group, but this was not confirmed by Eelora et al, 2005 [13–15]. The BRCA2 tumors are likely to be ER positive . BRCA1 mutation carriers have an earlier onset of ovarian cancer that is histologically high-grade serous adenocarcinoma . We had earlier published the data of BRCA1, BRCA2 and CHEK2*1100delC mutation status in 22 cases . Here, we report the clinico-pathological features, BRCA1, BRCA2 and CHEK2*1100delC mutation status and their correlation with prognostic markers in 91 cases.
Ninety-one eligible cases including the 22 published that fulfilled the criteria for gene testing were screened for BRCA1, BRCA2 and CHEK2*1100delC mutations . The criteria were as follows: Early onset of breast cancer (≤35 years of age) or ovarian cancer (≤40 years of age); Two cases of breast cancer diagnosed under the age of 50 years in a family (first and second degree relatives); Three or more cases of breast cancer diagnosed at any age; Presence of breast and ovarian cancer in the family or in the same individual; Male breast cancer with a relative (of either sex) with breast cancer; Family history of Prostate or pancreatic or colorectal cancer or sarcomas, with breast cancer in the family. The study includes 65 unilateral, 6 bilateral breast cancer cases, 14 ovarian cancer cases, 3 cases with both breast and ovarian cancer in the same individual without any family history of cancer, 2 cases each with family history of breast cancer and soft tissue sarcoma and 1 case of prostate cancer with family history of prostate and breast cancer. Of the 91 cases, 54 were with Family history (including 35 Hereditary Breast Cancer families, 15 Hereditary Breast & Ovarian Cancer families, 3 Hereditary Ovarian Cancer families and 1 with family history of Prostate and breast cancer). There were 31 early onset breast cancer (≤ 35 yrs) and 3 early onset ovarian cancer (≤ 40 yrs) cases without family history of cancer. Three patients had breast and ovarian cancers, without a family history. All the patients provided their informed consent for the study, which was cleared by the Institutional Ethical committee.
Mutation screening of BRCA1, BRCA2 and CHEK2*1100delC
The sample collection, DNA isolation, PCR-DHPLC and sequencing were carried out as previously described .
The secondary structure and the tertiary structure of the normal CHEK2 gene sequence and the two missense variants were predicted by submitting the sequences to Chou Fasman secondary structure prediction site and at ExPaSy server for tertiary structure prediction using Swiss model [19–22].
IHC was done for ER, PR, p53 and c-erbB2 expression studies on available breast cancer cases. IHC was performed as per the standard methodology using primary antibodies; clone ID5 (ER), clone PgR636 (PR), clone HER2/neu (c-erbB2), and clone DO7 (p53) and secondary antibodies; rabbit anti mouse for ER, PR and p53 and swine anti rabbit for c-erbB2 from Dako [23–26]. The antibodies were used at a dilution of 1:35 for ER and PR (Dako pharma), 1:350 for HER2/neu (Dako pharma) and 1:200 (Biogenex) or 1:50 (Dako pharma) for p53. Positive (known positives for each of the markers) and negative controls (omission of primary antibody) were included in each run. The scoring was done as described previously [23–26].
Chi-square test of independence was used for testing the statistical significance of association between the variables like age, stage, grade and histological type with disease status (i.e. disease free or disease present) and between clinico-pathological features and with each of the prognostic markers like ER, PR, c-erbB2 and p53 status for the breast cancer cases. The BRCA1 and BRCA2 mutation status i.e. mutation positivity or negativity were tested for statistical association with disease status and prognostic molecular markers. Yates correction was made wherever indicated. Fisher's exact probability test was employed to deal with small frequencies. Kaplan-Meier survival probabilities were computed for five-year survival data on Breast and Ovarian cancer cases separately, and differences were tested using the Log-rank test. All the statistical analyses were performed using Stata version 10.0 software.
BRCA1 and BRCA2 analysis
Gene, exon, mutation description, site of cancer in proband with age of onset and family history
Site of Cancer
Age of onset
[Acc No. AY144588]*
Mother – B (44 y)
MA – B (50 y)
MGM – B (50 y)
c.4327C>T; p.R1443X *
3 Sisters – B (35 y, 38 y, 48 y)
PA – B (64 y)
[Acc No. AY458144]
2 Sisters (50 and 49 y)
[Acc No. AY06912]
Breast (Metachronous Bil.) and uterine
2 sisters – B (39 y)
Mother – O (74 y)
[Acc No. DQ075361]
Mother – O (58 y)
p. Thr1675Thr fsX4
[Acc No. AY706913]
Daughter – O (39 y)
c.68_69delAG; p.Glu23Val fsX16
No family history
c.68_69delAG; p.Glu23Val fsX16
No family history
c.68_69delAG; p.Glu23Val fsX16
Mother – O (60 y)
c.68_69delAG; p.Glu23Val fsX16
Sister – O (44 y)
Daughter – B (39 y)
c.6214_6218delCTTAA; p.Ser2072Ser fsX4 *
Mother – B (40 y)
No family history
c.66_67delAG; p. Leu22Leu fsX18
Mother – B (41 y)
O (55 y)
MA – B (47 y)
[Acc No. FJ940752]
Mother – B (39 y)
MA – B (64 y)
Sister – B (33 y)
p. Ile873Ile fsX19
Mother – Cervix (40 y)
MGM – B (60 y)
PA – U (52 y)
The missense variations in the exons and the introns (defined polymorphisms in BIC database) of BRCA1 and BRCA2 gene and their percentage
Cases (n = 91)
Cases (n = 91)
3 – c.294A>G; p. L98L *
11K – c.2311T>C; p. L771L
10B – c.1114C>A; p. H372N
11N – c.2612C>T; p. P871L
10C – c.1365A>G; p. S455S
11S – c.3113A>G; p. E1038G
11B – c.4258G>T; p. D1420Y
11TU – c.3548A>G; p.K1183R
11C – c.4779A>C; p. E1593D
16 – c.4956G>A; p. M1652I
11F – c.2538A>C; p. S846S *
16 – c.4838A>G; p. S1613G
11H – c.2892A>T; p. K964N *
11P – c.2597G>T; p. R866L *
11I – c.2971A>G; p. N991D
11K – c.3807T>C; p. V1269V
c.547-64 del T
CHEK2*1100delC mutation analysis
IHC analysis, Clinico-Pathological Features and Statistical Analysis
Clinico-pathological characteristics of breast and Ovarian cancer cases
65 Unilateral breast cases in number (%)
6 Bilateral breast cases in number (%)
14 Ovarian cases in number (%)
Lt: 2(33.2%) Rt:1(16.6%)
Lt: 2(33.2%) Rt: -
Lt: – Rt:4(66.6%)
Lt: 2(33.2%) Rt:1(16.6%)
Lt: – Rt: -
Recurrence & disease present
Recurrence & disease free
Not treated at CI
Statistical analysis between clinico-pathological variables, disease status and prognostic markers revealed association between the stage of the disease at diagnosis and the disease status, which was statistically significant (p < 0.0035). There is a positive association between earlier stage at diagnosis and disease free status. No other variables like grade, age and histological types had significant association with the disease status and the prognostic molecular markers. In addition, no significant association between the mutation status and the clinico-pathological variables were seen.
In our study on 91 patients, 15 pathogenic mutations (16%) in BRCA1 and BRCA2 genes were detected. This is similar to the data from several studies including the study by Wagner et al who had reported 17% mutation in either of the BRCA genes [27–31].
There is a four fold greater incidence of BRCA1 mutation (12) compared to BRCA2 (3) mutations in our series of South Indian patients. This is different from the North Indian data wherein almost equal distribution of BRCA1 and BRCA2 mutations was seen in two studies and in the study by Hedau et al [32, 33], 4/24 mutations reported, were all in BRCA1 gene . The two South Indian studies have looked at BRCA1 mutations only [35, 36].
7/35 HBC families (20%) had mutations in either BRCA1 (5 mutations) or BRCA2 gene (2 mutations). Four of 15, HBOC cases were found to harbor mutations in BRCA1 gene (30%). Zelada-Hedman et al showed that 35% of the HBOC families have mutation in BRCA1 gene, but others report a higher percentage (58% and 43% respectively) of mutation in BRCA1 gene in HBOC families [28, 37, 38]. The German consortium (2002) study showed 10% mutation in BRCA2 gene in HBOC families . In our series we did not find mutation in BRCA2 gene in HBOC families, which is similar to the results from a study in the Japanese population . Three of 31 early onset (≤ 35 years) breast cancer cases had deleterious mutation, 2 in BRCA1 (7%) and 1 in BRCA2 (3%) gene. Peto et al also report 3.5% and 2.4% mutation in BRCA1 and BRCA2 gene, respectively in early onset (≤ 35 years) breast cancer cases . Of the three hereditary ovarian cancer families studied, one had a deleterious mutation in the BRCA1 gene.
Published results from various Indian groups on BRCA1 and BRCA2 mutation status on hereditary breast and ovarian cancer families or early onset breast cancer cases
Total No. cases
Authors and Year
14 cases with F/H of BC & OC
Kumar et al (2002)
20 cases with F/H of B & OC or early onset
(< 35 y)
2/20 (10%) (BRCA1)
Saxsena et al 2002
24 cases with F/H of breast cancer and 100 sporadic cases
BRCA 1 &BRCA2
6/24 (25%) (BRCA1)
Hedau el at 2004
16 cases F/H of BC & OC and 20 sporadic cases
5/16 (31%) (BRCA1 &BRCA2)
Valarmathi et al 2004
23 cases with F/H of BC & OC
Gajalakshmi et al 2006
204 cases, 34 with F/H, 105 early onset (<40 y) and 65 late onset
6/204 (2.9) (BRCA1 &BRCA2)
except for one mutation were seen either in early onset cases or with F/H
Saxena et al 2006
91 cases, 54 with F/H of BC & OC, 34 early onset (≤ 35 y for BC and ≤ 40 y for OC); 3 HBOC in same individual
15/91 (16%) (BRCA1 &BRCA2)
Many common missense variants were seen in our series both in the exon and intron of BRCA1 and BRCA2. Most have them been previously reported in other populations. The exonic variants seen in BRCA1 have been reported as unclassified variants in many studies [39, 42, 43]. In the BIC data base, most of the variants have been classified as having no clinical significance or of unknown clinical significance. Case control studies have shown no difference in the frequencies of these alleles in cases and controls . However, we have not analyzed the frequency of the missense heterozygotes in our control population i.e. unaffected controls with out any family history of breast and/or ovarian cancer. The most common exonic missense variant of BRCA2 gene seen in our cases was N372H. Studies have shown that N372H appears to confer a small increased risk for breast cancer . The missense variants seen in the intronic region of the BRCA1 gene and other less common exonic and intronic variants in BRCA2 have also been previously reported in other populations [28, 37, 38, 40].
The CHEK2* 1100delC mutation reported in the western populations were also screened for in our cases. Though no CHEK2* 1100delC mutation was detected, two missense mutations in the CHEK2 gene (p.R406H and p.A392V) were seen in three cases. The residues, arginine and alanine at positions 406 and 392 are conserved across species. Additionally, the secondary structure prediction using the Chou-Fasman algorithm predicts changes in the secondary structure for both the missense variations .
The Swiss Model software too shows a marked change in the structure for the A392V missense variation, though the R406H did not show a visible change. The variation (R406H) was not seen to be associated with breast cancer cases in French Canadian women . The pathogenicity of the variations can however be confirmed by segregation analysis in other affected family members or other functional studies or screening the normal controls. Two out of the three cases had a family history of breast cancer but we could not get the sample from the other affected family member for testing. The patient with the A392V mutation was an early onset breast cancer patient without any family history. Rest of the coding region of the CHEK2 gene was not screened for mutations.
In our series, nearly 80% of the breast cancer patients were ≤ 45 years of age at diagnosis, with 52.7% being ≤ 35 years at diagnosis, as in other studies . Majority of the breast cancer cases were high-grade tumors (56%). Ho et al reported that 25%–37% of hereditary breast cancers not associated with BRCA1 mutations were ER negative but we found 68% to be negative for ER expression in our study . This correlates well with our hospital statistics in sporadic cancers, wherein 62% of the pre-menopausal patients harbor tumours, which are ER negative.
Our study looked at the association between clinico-pathological features, disease status, and prognostic markers. We also looked at the association between the mutation status with disease status and prognostic markers. The stage of the disease at diagnosis and the disease status alone emerged to be statistically significant, wherein a positive association between earlier stage at diagnosis and disease free status was observed. None of the other parameters showed any association. Disease free and overall survival of BRCA mutation positive breast or ovarian cancers did not significantly differ from the BRCA mutation negative cases. Other groups have also not found any survival difference between BRCA mutation positive versus negative cases [46–49].
Of the 91 cases analyzed, 13 (14%) of the affected probands were issues of consanguineous marriage and had either ovarian cancers (3) or breast cancers (10). Though susceptibility to breast cancer is inhereited as an autosomal dominant trait, modifier genes when present in homozygous state might further increase the risk of cancer.
We have looked at the prevalence of BRCA1, BRCA2 and CHEK 1100delC mutation in breast and ovarain caner patients in India. The prevalence of BRCA1 and BRCA2 gene mutaion is similar to other population. CHEK 1100delC mutation was not seen our study series. Asoociation between the clinico-pathological variables and mutation status with disease status and prognostic markers revealed significant assocaition between the stage at diagnosis and disease free status alone.
This study was supported by the Dept. of Biotechnology grant no: BT/PR2649/Med/09/370/2001. The ABI Prism 310 genetic analyzer was a kind donation of Chennai Willingdon Corporate Foundation.
- Shanta V, Swaminathan R: Cancer incidence and mortality in Chennai, India 2003–2005. National Cancer registry program, Cancer Institute (WIA), Chennai 2008.Google Scholar
- Sue Moss: Screening for breast cancer in India – is it an appropriate strategy? J Natl Cancer Inst 2008, 100(18):1290–1300. 10.1093/jnci/djn292View ArticleGoogle Scholar
- Miki Y, Swensen J, Donna Shattuck-Eidens, Futreal PA, Harshman K, Tavtigian S, Qingyun Liu, Cochran C, Bennett LM, Ding W, Bell R, Rosenthal J, Hussey C, Tran T, McClure M, Frye C, Hattier T, Phelps R, Haugen-Strano A, Katcher H, Yakumo K, Gholami Z, Shaffer D, Stone S, Bayer S, Wray C, Bogden R, Dayananth P, Ward J, Tonin P, Narod S, Bristow PK, Norris FH, Helvering L, Morrison P, Rosteck P, Lai M, Barrett JC, Lewis C, Neuhausen S, Cannon-Albright L, Goldgar D, Wiseman R, Kamb A, Skolnick MH: A strong candidate for the breast and ovarian cancer susceptibility gene BRCA1 . Science 1994, 266: 66–71. 10.1126/science.7545954View ArticlePubMedGoogle Scholar
- Wooster R, Bignell G, Lancaster J, Swift S, Seal S, Mangion J, Collins N, Gregory S, Gumbs C, Micklem G: Identification of the breast cancer susceptibility gene BRCA2 . Nature 1995, 378: 789–92. 10.1038/378789a0View ArticlePubMedGoogle Scholar
- Heijboer HM, Ouweland Ans, Klijn J, Wasielewski M, Snoo A, Oldenburg R, Hollestelle A, Houben M, Crepin E, Veghel-Plandsoen M, Elstrodt F, Duijn C, Bartels C, Meijers C, Schutte M, McGuffog L, Thompson D, Easton DF, Sodha N, Seal S, Barfoot R, Mangion J, Chang-Claude J, Eccles D, Eeles R, Gareth Evans D, Houlston R, Murday V, Narod S, Peretz T, Julian P, Phelan C, Zhang HX, Szebo C, Derilee P, Goldgar D, Futreal PA, Nathanson KL, Weber BL, Rahman N, Stratton MR: Low-penetrance susceptibility to breast cancer due to CHEK2 *1100delC in non-carriers of BRCA1 or BRCA2 mutations: The CHEK2 breast cancer consortium. Nat Genet 2002, 31: 55–59. 10.1038/ng879View ArticleGoogle Scholar
- Antoniou A, Pharoah PD, Narod S, Risch HA, Eyfjord JE, Hopper JL, Loman N, Olsson H, Johannsson O, Borg A, Pasini B, Radice P, Manoukian S, Eccles DM, Tang N, Olah E, Anton-Culver H, Warner E, Lubinski J, Gronwald J, Gorski B, Tulinius H, Thorlacius S, Eerola H, Nevanlinna H, Syrjäkoski K, Kallioniemi OP, Thompson D, Evans C, Peto J, Lalloo F, Evans DG, Easton DF: Average risks of breast and ovarian cancer associated with BRCA1 or BRCA2 mutations detected in case Series unselected for family history: a combined analysis of 22 studies. Am J Hum Genet 2003, 72: 1117–30. 10.1086/375033View ArticlePubMedPubMed CentralGoogle Scholar
- Ford D, Easton DF, Bishop DT, Narod SA, Goldgar DE: Risks of cancer in BRCA1 -mutation carriers. Breast Cancer Linkage Consortium. Lancet 1994, 343: 692–695. 10.1016/S0140-6736(94)91578-4View ArticlePubMedGoogle Scholar
- Robson ME: Clinical Considerations in the Management of Individuals at Risk for Hereditary Breast and Ovarian Cancer. Cancer Control 2002, 9: 457–465.PubMedGoogle Scholar
- Marsh DJ, Zori RT: Genetic insights into familial cancers-update and recent discoveries. Cancer Letters 2002, 181: 125–164.View ArticlePubMedGoogle Scholar
- Easton DF, Pooley KA, Dunning AM, Pharoah PD, Thompson D, Ballinger DG, Struewing JP, Morrison J, Field H, Luben R, Wareham N, Ahmed S, Healey CS, Bowman R, SEARCH collaborators, Meyer KB, Haiman CA, Kolonel LK, Henderson BE, Le Marchand L, Brennan P, Sangrajrang S, Gaborieau V, Odefrey F, Shen CY, Wu PE, Wang HC, Eccles D, Evans DG, Peto J, Fletcher O, Johnson N, Seal S, Stratton MR, Rahman N, Chenevix-Trench G, Bojesen SE, Nordestgaard BG, Axelsson CK, Garcia-Closas M, Brinton L, Chanock S, Lissowska J, Peplonska B, Nevanlinna H, Fagerholm R, Eerola H, Kang D, Yoo KY, Noh DY, Ahn SH, Hunter DJ, Hankinson SE, Cox DG, Hall P, Wedren S, Liu J, Low YL, Bogdanova N, Schürmann P, Dörk T, Tollenaar RA, Jacobi CE, Devilee P, Klijn JG, Sigurdson AJ, Doody MM, Alexander BH, Zhang J, Cox A, Brock IW, MacPherson G, Reed MW, Couch FJ, Goode EL, Olson JE, Meijers-Heijboer H, Ouweland A, Uitterlinden A, Rivadeneira F, Milne RL, Ribas G, Gonzalez-Neira A, Benitez J, Hopper JL, McCredie M, Southey M, Giles GG, Schroen C, Justenhoven C, Brauch H, Hamann U, Ko YD, Spurdle AB, Beesley J, Chen X, kConFab AOCS Management Group, Mannermaa A, Kosma VM, Kataja V, Hartikainen J, Day NE, Cox DR, Ponder BA: Genome-wide association study identifies novel breast cancer susceptibility loci. Nature 2007, 447: 1087–1093. 10.1038/nature05887View ArticlePubMedPubMed CentralGoogle Scholar
- Lakhani SR, Jacquemier J, Sloane JP, Gusterson BA, Anderson TJ, Vijver MJ, Farid LM, Venter D, Antoniou A, Storfer-Isser A, Smyth E, Steel CM, Haites N, Scott RJ, Goldgar D, Neuhausen S, Daly PA, Ormiston W, McManus R, Scherneck S, Ponder BA, Ford D, Peto J, Stoppa-Lyonnet D, Easton DF: Multifactorial analysis of differences between sporadic breast cancer and cancers involving BRCA1 and BRCA2 mutation. J Natl Cancer Inst 1998, 80: 1138–1145. 10.1093/jnci/90.15.1138View ArticleGoogle Scholar
- Berns EM, Van Staveren IL, Verhoog L, Van De Ouweland AM, Gelder MM, Meijers-Heijboer H, Portengen H, Foekens JA, Dorssers LC, Klijn JG: Molecular profiles of BRCA1 - mutated and matched sporadic breast tumors; relation with clinico-pathological features. British J Cancer 2001, 85: 538–545. 10.1054/bjoc.2001.1937View ArticleGoogle Scholar
- Lakhani SR: The pathology of familial breast cancer: morphological aspects. Breast Cancer Res 1999, 1: 31–35. 10.1186/bcr10View ArticlePubMedPubMed CentralGoogle Scholar
- Bell DW, Erban J, Sgroi DC, Haber DA: Selective loss of heterozygosity in multiple breast cancers from a carrier of mutations in both BRCA1 and BRCA2 . Cancer Res 2002, 62: 2741–2743.PubMedGoogle Scholar
- Eerola H, Heikkilä P, Tamminen A, Aittomäki K, Blomqvist C, Nevanlinna H: A Histopathological features of breast tumours in BRCA1, BRCA2 and mutation-negative breast cancer families. Breast Cancer Res 2005, 7: R93-R100. 10.1186/bcr953View ArticlePubMedGoogle Scholar
- De Carvalho M, Jenkins J, Nehrebecky M, Lahl L: The Role of Estrogens in BRCA1/2 Mutation Carriers. Cancer Nurs 2003, 26: 421–430.View ArticlePubMedGoogle Scholar
- Rubin SC, Benjamin I, Behbakht K, Takahashi H, Morgan MA, LiVolsi VA, Berchuck A, Muto MG, Garber JE, Weber BL, Lynch HT, Boyd J: Clinical And Pathological Features Of Ovarian Cancer In Women With Germ-Line Mutations Of Brca1 . N Engl J Med 1996, 335: 1413–1416. 10.1056/NEJM199611073351901View ArticlePubMedGoogle Scholar
- Rajkumar T, Soumittra N, Nirmala KN, Swaminathan R, Sridevi V, Shanta V: BRCA1, BRCA2 And CHEK2 (1100 Del C) Germline Mutations In Hereditary Breast And Ovarian Cancer Families In South India. APJCP 2003, 4: 203–208.PubMedGoogle Scholar
- Schwede T, Kopp J, Guex N, Peitsch MC: SWISS-MODEL: an automated protein homology-modeling server. Nucleic Acids Research 2003, 31: 3381–3385. 10.1093/nar/gkg520View ArticlePubMedPubMed CentralGoogle Scholar
- Guex N, Peitsch MC: SWISS-MODEL and the Swiss-PdbViewer An environment for comparative protein modelling. Electrophoresis 1997, 18: 2714–2723. 10.1002/elps.1150181505View ArticlePubMedGoogle Scholar
- Peitsch MC: Protein modeling by E-mail Bio/Technology. 1995, 13: 658–660.Google Scholar
- Thorpe SM, Rose C: Estrogen and progesterone receptor determinations in breast cancer technology and biology. Cancer Surv 1986, 5: 505–525.PubMedGoogle Scholar
- Lee A, Park WC, Yim HW, Lee MA, Park G, Lee KY: Expression of c-ErbB2, Cyclin D1 and ER and their clinical implications in Invasive ductal carcinoma of breast. Jpn J Clin Oncol 2007, 37(9):708–714. 10.1093/jjco/hym082View ArticlePubMedGoogle Scholar
- Gullick WJ: Expression of c-ErbB2 protooncogene protein in human breast cancer. Recent results. Cancer Res 1989, 113: 51–56.Google Scholar
- Geisler S, Lønning PE, Aas T, Johnsen H, Fluge O, Haugen DF, Lillehaug JR, Akslen LR, Anne-Lise Børresen-Dale: Influence of Tp53 gene alterations and c-erbB2 expression on the response to treatment with doxorubicin in locally advanced breast cancer. Cancer Res 2001, 61: 2501–2512.Google Scholar
- Wagner TM, Hirtenlehner K, Shen P, Moeslinger R, Muhr D, Fleischmann E, Concin H, Doeller W, Haid A, Lang AH, Mayer P, Petru E, Ropp E, Langbauer G, Kubista E, Scheiner O, Underhill P, Mountain J, Stierer M, Zielinski C, Oefner P: Global sequence diversity of BRCA2 : analysis of 71 breast cancer families and 95 control individuals of worldwide populations. Hum Mol Genet 1999, 8: 413–23. 10.1093/hmg/8.3.413View ArticlePubMedGoogle Scholar
- Wagner TM, Möslinger RA, Muhr D, Langbauer G, Hirtenlehner K, Concin H, Doeller W, Haid A, Lang AH, Mayer P, Ropp E, Kubista E, Amirimani B, Helbich T, Becherer A, Scheiner O, Breiteneder H, Borg A, Devilee P, Oefner P, Zielinski C: BRCA1 – related breast cancer in Austrian breast and ovarian cancer families: specific BRCA1 mutations and pathological characteristics. Int J Cancer 1998, 77: 354–360. 10.1002/(SICI)1097-0215(19980729)77:3<354::AID-IJC8>3.0.CO;2-NView ArticlePubMedGoogle Scholar
- Risch HA, McLaughlin JR, Cole DE, Rosen B, Bradley L, Kwan E, Jack E, Vesprini DJ, Kuperstein G, Abrahamson JL, Fan I, Wong B, Narod SA: Prevalence and Penetrance of Germline BRCA1 and BRCA2 Mutations in a Population Series of 649 Women with Ovarian Cancer. Am. J. Hum 2001, 68: 700–710. 10.1086/318787View ArticleGoogle Scholar
- Palmieri G, Palomba G, Cossu A, Pisano M, Dedola MF, Sarobba MG, Farris A, Olmeo N, Contu A, Pasca A, Satta MP, Persico I, Carboni AA, Cossu-Rocca P, Contini M, Mangion J, Stratton MR, Tanda F: BRCA1 and BRCA2 Germline mutations in Sardinian breast cancer families and their implications for genetic counseling. Ann Oncol 2002, 13: 1899–1907. 10.1093/annonc/mdf326View ArticlePubMedGoogle Scholar
- Thirthagiri E, Lee SY, Kang P, Lee DS, Toh GT, Selamat S, Yoon SY, Taib NA, Thong MK, Yip CH, Teo SH: Evaluation of BRCA1 and BRCA2 mutation and risk prediction models in Asian country (Malaysia) with a relatively low incidence of breast cancer. Breast Cancer Res 2008, 10: R59. 10.1186/bcr2118View ArticlePubMedPubMed CentralGoogle Scholar
- Saxena S, Chakraborty A, Kaushal M, Kotwal S, Bhatanager D, Mohil RS, Chintamani C, Aggarwal AK, Sharma VK, Sharma PC, Lenoir G, Goldgar DE, Szabo CI: Contribution of germline BRCA1 and BRCA2 sequence alterations to breast cancer in Northern India. BMC Medical Genetics 2006, 7: 1471–2350. 10.1186/1471-2350-7-75View ArticleGoogle Scholar
- Kumar BV, Lakhotia S, Ankathil R, Madhavan J, Jayaprakash PG, Nair MK, Somasundaram K: Germline BRCA1 mutation analysis in Indian breast/ovarian cancer families. Cancer Biol Ther 2002, 1: 18–21.View ArticlePubMedGoogle Scholar
- Saxena S, Szabo CI, Chopin S, Barjhoux L, Sinilnikova O, Lenoir G, Goldgar DE, Bhatanager D: BRCA1 and BRCA2 in Indian breast cancer patients. Hum Mutat 2002, 20: 473–474. 10.1002/humu.9082View ArticlePubMedGoogle Scholar
- Hedau S, Jain N, Husain SA, Mandal AK, Ray G, Shahid M, Kant R, Gupta V, Shukla NK, Deo SS, Das BC: Novel germline mutations in breast cancer susceptibility genes BRCA 1, BRCA 2 and p53 gene in breast cancer patients from India. Breast Cancer Res Treat 2004, 88: 177–86. 10.1007/s10549-004-0593-8View ArticlePubMedGoogle Scholar
- Valarmathi MT, Sawhney M, Deo SS, Shukla NK, Das SN: Novel germline mutations in the BRCA1 and BRCA2 genes in Indian breast and breast-ovarian cancer families. Hum Mutat 2004, 23: 205. 10.1002/humu.9213View ArticlePubMedGoogle Scholar
- Zelada-Hedman M, Wasteson Arver B, Claro A, Chen J, Werelius B, Kok H, Sandelin K, Håkansson S, Andersen TI, Borg A, Børresen Dale AL, Lindblom A: A screening for BRCA1 mutations in breast and breast-ovarian cancer families from Stockholm region. Cancer Res 1997, 37: 2474–2477.Google Scholar
- Meindl A: German consortium for hereditary breast and ovarian cancer: Comprehensive analysis of 989 patients with breast or ovarian cancer provides BRCA1 and BRCA2 mutation profiles and frequencies for the German population. Int J Cancer 2002, 97: 472–480. 10.1002/ijc.1626View ArticlePubMedGoogle Scholar
- Ikeda N, Miyoshi Y, Yoneda K, Shiba E, Sekihara Y, Kinoshita M, Noguchi S: Fequency of BRCA1 and BRCA2 germline mutations in Japanese breast cancer families. Int J Cancer 2001, 91: 83–88. 10.1002/1097-0215(20010101)91:1<83::AID-IJC1013>3.0.CO;2-5View ArticlePubMedGoogle Scholar
- Peto J, Collins N, Barfoot R, Seal S, Warren W, Rahman N, Easton DF, Evans C, Deacon J, Stratton MR: Prevalance of BRCA1 and BRCA2 gene Mutations in patients with early-onset breast cancer. J Natl Cancer Inst 1999, 91: 943–949. 10.1093/jnci/91.11.943View ArticlePubMedGoogle Scholar
- Gajalakshmi P, Natarajan TG, Rani DS, Thangaraj K: A novel BRCA1 mutation in an Indian family with hereditary breast/ovarian cancer. Breast Cancer Res Treat 2006.Google Scholar
- Ho GH, Phang BH, Ng IS, Law HY, Soo KC, Ng EH: Novel germline BRCA 1 mutations detected in women in Singapore who developed breast carcinoma before the age of 36 years. Cancer 2000, 89: 811–816. 10.1002/1097-0142(20000815)89:4<811::AID-CNCR13>3.0.CO;2-RView ArticlePubMedGoogle Scholar
- Friedman LS, Ostermeyer EA, Szabo CI, Dowd P, Lynch ED, Rowell SE, King MC: Conformation of BRCA 1 by analysis of germline mutations linked to breast and ovarian cancer in ten families. Nat Genet 1994, 8: 399–404. 10.1038/ng1294-399View ArticlePubMedGoogle Scholar
- Nathanson KL, Weber BL: "Other" breast caner susceptibility genes searching for more holy grail. Hum Mol Genet 2001, 10: 715–720. 10.1093/hmg/10.7.715View ArticlePubMedGoogle Scholar
- Novak DJ, Chen LQ, Ghadirian P, Hamel N, Zhang P, Rossiny V, Cardinal G, Robidoux A, Tonin PN, Rousseau F, Narod SA, Foulkes WD: Identification of a novel CHEK2 variant and assessment of its contribution to the risk of breast cancer in French Canadian Women. BMC Cancer 2008, 8: 239. 10.1186/1471-2407-8-239View ArticlePubMedPubMed CentralGoogle Scholar
- Verhoog LC, Brekelmans CT, Seynaeve C, Bosch LM, Dahmen G, van Geel AN, Tilanus-Linthorst MM, Bartels CC, Wagner A, Ouweland A, Devilee P, Meijers-Heijboer EJ, Klijn JG: Survival and tumor characteristics of breast cancer patients with germline mutations of BRCA1 . Lancet 1998, 351: 316–321. 10.1016/S0140-6736(97)07065-7View ArticlePubMedGoogle Scholar
- Johannsson OT, Ranstam J, Borg A, Olsson H: Survival of BRCA1 breast and ovarian cancer patients: a population-based study from southern Swden. J Clin Oncol 1998, 16: 397–404.PubMedGoogle Scholar
- Lee JS, Wacholder S, Struewing JP, McAdams M, Pee D, Brody LC, Tucker MA, Hartge P: Survival after breast cancer in Ashkenazi Jewish BRCA1 and BRCA2 mutation carriers. J Natl Cancer Inst 1999, 91: 259–263. 10.1093/jnci/91.3.259View ArticlePubMedGoogle Scholar
- Robson M, Gilewski T, Haas B, Levin D, Borgen P, Rajan P, Hirschaut Y, Pressman P, Rosen PP, Lesser ML, Norton L, Offit K: BRCA -aasociated breast cancer in young women. J Clin Oncol 1998, 16: 1642–1649.PubMedGoogle Scholar
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.