iPSC-Derived Hereditary Breast Cancer Model Reveals the BRCA1-Deleted Tumor Niche as a New Culprit in Disease Progression.

Tumor progression begins when cancer cells recruit tumor-associated stromal cells to produce a vascular niche, ultimately resulting in uncontrolled growth, invasion, and metastasis. It is poorly understood, though, how this process might be affected by deletions or mutations in the breast cancer type 1 susceptibility (BRCA1) gene in patients with a lifetime risk of developing breast and/or ovarian cancer. To model the BRCA1-deleted stroma, we first generated induced pluripotent stem cells (iPSCs) from patients carrying a germline deletion of exon 17 of the BRCA1 gene (BRCA1+/- who, based on their family histories, were at a high risk for cancer. Using peripheral blood mononuclear cells (PBMCs) of these two affected family members and two normal (BRCA1+/+) individuals, we established a number of iPSC clones via non-integrating Sendai virus-based delivery of the four OCT4, SOX2, KLF4, and c-MYC factors. Induced mesenchymal stem cells (iMSCs) were generated and used as normal and pathological stromal cells. In transcriptome analyses, BRCA1+/- iMSCs exhibited a unique pro-angiogenic signature: compared to non-mutated iMSCs, they expressed high levels of HIF-1α, angiogenic factors belonging to the VEGF, PDGF, and ANGPT subfamilies showing high angiogenic potential. This was confirmed in vitro through the increased capacity to generate tube-like structures compared to BRCA1+/+ iMSCs and in vivo by a matrigel plug angiogenesis assay where the BRCA1+/- iMSCs promoted the development of an extended and organized vessel network. We also reported a highly increased migration capacity of BRCA1+/- iMSCs through an in vitro wound healing assay that correlated with the upregulation of the periostin (POSTN). Finally, we assessed the ability of both iMSCs to facilitate the engraftment of murine breast cancer cells using a xenogenic 4T1 transplant model. The co-injection of BRCA1+/- iMSCs and 4T1 breast cancer cells into mouse mammary fat pads gave rise to highly aggressive tumor growth (2-fold increase in tumor volume compared to 4T1 alone, p = 0.01283) and a higher prevalence of spontaneous metastatic spread to the lungs. Here, we report for the first time a major effect of BRCA1 haploinsufficiency on tumor-associated stroma in the context of BRCA1-associated cancers. The unique iMSC model used here was generated using patient-specific iPSCs, which opens new therapeutic avenues for the prevention and personalized treatment of BRCA1-associated hereditary breast cancer.

C-Arm-Free Minimally Invasive Cervical Pedicle Screw Fixation (MICEPS): A Technical Note.

A minimally invasive posterolateral approach designed to avoid the lateral misplacement of midcervical pedicle screws was reported, but there is no technical report that describes this technique without C-arm fluoroscopy. We report the results of a 2.5 years follow-up of a 62-year-old female patient with C4 metastatic breast cancer. The patient suffered from severe neck pain and impending quadriplegia for 2 months after radiation therapy. We performed C-arm-free minimally invasive cervical pedicle screw fixation (MICEPS). The patient was suc-cessfully treated with surgery, and her neck pain was well controlled. She had neither neurological deficits nor neck pain at the final (2.5-year) follow-up. C-arm-free MICEPS is a useful technique; in addition, the sur-geons and staff have no risk of radiation exposure, there is a reduced need for postoperative imaging, and a decreased revision rate can be expected with C-arm-free MICEPS.

Large Congenital Melanocytic Nevus on the Breast Sparing the Nipple and Areola.

BACKGROUND: Divided nevus is a rare entity that has been described for a special appearance of congenital melanocytic nevi (CMNs) occurring on the eyelid and penis. It is presumed that the formation of divided nevi is related with the embryologic development of the eyelid and penis, thus giving a hint about the occurrence time of CMN in utero. This article focuses on a formerly undescribed observation of another special clinical appearance of CMN discussing possible relation with embryogenesis. METHODS: The data including photographic documentations of a total number of 86 patients with large CMN seen in a single center were reviewed according to the involvement of the nipple and areola by the main mass of the nevus and associated satellite lesions. RESULTS: Eight patients presented with CMNs involving one (n=6) or both (n=2) breast region. In all of them, CMN surrounded the nipple-areola complex without involving these structures. Furthermore, satellite nevi have not been observed on the nipple and areola in any of the 86 patients. CONCLUSION: We presume that different developmental time periods of the breast and the nipple-areola complex and the occurrence of the melanocytic lesion before the embryologic development of nipple-areola complex could explain our observation of CMN sparing the nipple-areola complex. The term "nipple-sparing nevus of the breast" is suggested for this special clinical appearance of CMN.

Breast-cancer risk in families with mutations in PALB2.

BACKGROUND: Germline loss-of-function mutations in PALB2 are known to confer a predisposition to breast cancer. However, the lifetime risk of breast cancer that is conferred by such mutations remains unknown. METHODS: We analyzed the risk of breast cancer among 362 members of 154 families who had deleterious truncating, splice, or deletion mutations in PALB2. The age-specific breast-cancer risk for mutation carriers was estimated with the use of a modified segregation-analysis approach that allowed for the effects of PALB2 genotype and residual familial aggregation. RESULTS: The risk of breast cancer for female PALB2 mutation carriers, as compared with the general population, was eight to nine times as high among those younger than 40 years of age, six to eight times as high among those 40 to 60 years of age, and five times as high among those older than 60 years of age. The estimated cumulative risk of breast cancer among female mutation carriers was 14% (95% confidence interval [CI], 9 to 20) by 50 years of age and 35% (95% CI, 26 to 46) by 70 years of age. Breast-cancer risk was also significantly influenced by birth cohort (P<0.001) and by other familial factors (P=0.04). The absolute breast-cancer risk for PALB2 female mutation carriers by 70 years of age ranged from 33% (95% CI, 25 to 44) for those with no family history of breast cancer to 58% (95% CI, 50 to 66) for those with two or more first-degree relatives with breast cancer at 50 years of age. CONCLUSIONS: Loss-of-function mutations in PALB2 are an important cause of hereditary breast cancer, with respect both to the frequency of cancer-predisposing mutations and to the risk associated with them. Our data suggest the breast-cancer risk for PALB2 mutation carriers may overlap with that for BRCA2 mutation carriers. (Funded by the European Research Council and others.).

Genetic anticipation of familial breast cancer with or without BRCA mutation in the Korean population.

We investigated genetic anticipation of breast or ovarian cancer in patients with familial breast cancer. Among 201 patients with breast cancer who had a family history of breast or ovarian cancer, 95 families had affected familial members in the previous generation. Of these families, 2 were excluded because of insufficient data. From the 93 eligible families, 112 and 111 members were identified in the previous and proband generations, respectively. BRCA mutations were detected in 26 (28.0%) of the 93 probands. The median age at diagnosis of the first generation was 57 years and of the second generation was 40 years, which was a significant difference. The result from the mixed-effects model also demonstrated significant genetic anticipation (P < 0.0001). The expected age difference at onset of breast or ovarian cancer between the two generations was 17.06 years. BRCA mutation status did not influence the generational difference in age at diagnosis (17.99 vs. 16.62 y, P = 0.3973). Genetic counseling and early screening should be provided to women whose parent had a breast or ovarian cancer diagnosis.

Mitochondrial DNA variants and risk of familial breast cancer: an exploratory study.

To assess if mitochondrial DNA (mtDNA) variants are associated with mutations in BRCA susceptibility genes and to investigate the possible role of mitochondrial alterations as susceptibility markers in familial breast cancer (BC), 22 patients with or without BRCA1/BRCA2 mutations, 14 sporadic BC patients and 20 healthy subjects were analyzed. In the D-loop and in the MTND4 region, variants significantly associated with BRCA1 carriers were identified. Moreover, examination of mitochondrial haplogroups revealed X as the most significantly frequent haplogroup in BRCA1 carriers (P=0.005), and H as significantly linked to BRCA2 carriers (P=0.05). Our data suggest the involvement of the mitochondrial genome in the pathogenetic and molecular mechanism of familial BC disease.

RNA profiling reveals familial aggregation of molecular subtypes in non-BRCA1/2 breast cancer families.

BACKGROUND: In more than 70% of families with a strong history of breast and ovarian cancers, pathogenic mutation in BRCA1 or BRCA2 cannot be identified, even though hereditary factors are expected to be involved. It has been proposed that tumors with similar molecular phenotypes also share similar underlying pathophysiological mechanisms. In the current study, the aim was to investigate if global RNA profiling can be used to identify functional subgroups within breast tumors from families tested negative for BRCA1/2 germline mutations and how these subgroupings relate to different breast cancer patients within the same family. METHODS: In the current study we analyzed a collection of 70 frozen breast tumor biopsies from a total of 58 families by global RNA profiling and promoter methylation analysis. RESULTS: We show that distinct functional subgroupings, similar to the intrinsic molecular breast cancer subtypes, exist among non-BRCA1/2 breast cancers. The distribution of subtypes was markedly different from the distribution found among BRCA1/2 mutation carriers. From 11 breast cancer families, breast tumor biopsies from more than one affected family member were included in the study. Notably, in 8 of these families we found that patients from the same family shared the same tumor subtype, showing a tendency of familial aggregation of tumor subtypes (p-value = 1.7e-3). Using our previously developed BRCA1/2-signatures, we identified 7 non-BRCA1/2 tumors with a BRCA1-like molecular phenotype and provide evidence for epigenetic inactivation of BRCA1 in three of the tumors. In addition, 7 BRCA2-like tumors were found. CONCLUSIONS: Our finding indicates involvement of hereditary factors in non-BRCA1/2 breast cancer families in which family members may carry genetic susceptibility not just to breast cancer but to a particular subtype of breast cancer. This is the first study to provide a biological link between breast cancers from family members of high-risk non-BRCA1/2 families in a systematic manner, suggesting that future genetic analysis may benefit from subgrouping families into molecularly homogeneous subtypes in order to search for new high penetrance susceptibility genes.

Mutation analysis of the ERCC4/FANCQ gene in hereditary breast cancer.

The ERCC4 protein forms a structure-specific endonuclease involved in the DNA damage response. Different cancer syndromes such as a subtype of Xeroderma pigmentosum, XPF, and recently a subtype of Fanconi Anemia, FA-Q, have been attributed to biallelic ERCC4 gene mutations. To investigate whether monoallelic ERCC4 gene defects play some role in the inherited component of breast cancer susceptibility, we sequenced the whole ERCC4 coding region and flanking untranslated portions in a series of 101 Byelorussian and German breast cancer patients selected for familial disease (set 1, n = 63) or for the presence of the rs1800067 risk haplotype (set 2, n = 38). This study confirmed six known and one novel exonic variants, including four missense substitutions but no truncating mutation. Missense substitution p.R415Q (rs1800067), a previously postulated breast cancer susceptibility allele, was subsequently screened for in a total of 3,698 breast cancer cases and 2,868 controls from Germany, Belarus or Russia. The Gln415 allele appeared protective against breast cancer in the German series, with the strongest effect for ductal histology (OR 0.67; 95%CI 0.49; 0.92; p = 0.003), but this association was not confirmed in the other two series, with the combined analysis yielding an overall Mantel-Haenszel OR of 0.94 (95% CI 0.81; 1.08). There was no significant effect of p.R415Q on breast cancer survival in the German patient series. The other three detected ERCC4 missense mutations included two known rare variants as well as a novel substitution, p.E17V, that we identified on a p.R415Q haplotype background. The p.E17V mutation is predicted to be probably damaging but was present in just one heterozygous patient. We conclude that the contribution of ERCC4/FANCQ coding mutations to hereditary breast cancer in Central and Eastern Europe is likely to be small.

Etiology of familial breast cancer with undetected BRCA1 and BRCA2 mutations: clinical implications.

BACKGROUND: Familial breast cancer accounts for 20-30 % of all breast cancer cases. Mutations in the BRCA1 and BRCA2 genes account for the majority of high risk families with both early onset breast cancer and ovarian cancer. Most of the families with less than six breast cancer cases and no ovarian cancer do not carry BRCA1 or BRCA2 mutations that can be detected using routine sequencing protocols. Here, we aimed to review the etiology of familial breast cancer in cases without BRCA1 and BRCA2 mutations. RESULTS: After excluding BRCA1 and BRCA2 mutations, factors proposed to contribute to familial breast cancer include: chance clustering of apparently sporadic cases, shared lifestyle, monogenic inheritance, i.e., dominant gene mutations associated with a high risk (TP53, PTEN, STK11), dominant gene mutations associated with a relatively low risk (ATM, BRIP1, RLB2), recessive gene mutations associated with horizontal inheritance patterns (sister-sister), and polygenic inheritance where susceptibility to familial breast cancer is thought to be conferred by a large number of low risk alleles. CONCLUSIONS: Current evidence suggests that in the majority of cases with BRCA1 and BRCA2 negative familial breast cancer the etiology is due to interactions of intermediate or low risk alleles with environmental and lifestyle factors. Thus, a careful selection of patients submitted to genetic testing is needed. Clearly, further research is required to fully elucidate the etiology of non-BRCA familial breast cancer.

Family history and BRCA1/BRCA2 status among Japanese ovarian cancer patients and occult cancer in a BRCA1 mutant case.

BACKGROUND: This study aimed to examine family history among Japanese ovarian cancer patients and to investigate the TP53 status of fallopian tube epithelial and ovarian cancer cells in a Japanese BRCA1 mutant case that may be associated with the transformed state in hereditary ovarian cancer. METHODS: One hundred and two primary ovarian cancer patients were retrospectively evaluated in this cross-sectional study. The family history of cancer was determined in probands. In a BRCA1 mutant case, p53 immunostaining and direct sequencing, followed by laser-capture microdissection, were performed for the fallopian tube, considered the origin of ovarian cancer. RESULTS: Nine of 102 (8.8%) families were regarded as having hereditary breast-ovarian cancer syndrome, two families (2.0%) were diagnosed with Lynch syndrome and six patients harbored BRCA1 or BRCA2 mutations. One case underwent risk-reductive salpingo-oophorectomy as a BRCA1 mutant carrier was retrospectively diagnosed as occult cancer. Common TP53 mutations were detected in cancer and fallopian tube epithelial cells in the case. CONCLUSIONS: Here, we integrate family cancer history and histology in ovarian cancer cases as well as TP53 status in a BRCA1 mutant case into a discussion regarding carcinogenesis in a Japanese population. The TP53 status for the BRCA1 mutant case examined here supports the recently proposed theory that ovarian cancer develops because of BRCA1 or BRCA2 inactivation and/or TP53 mutations.

Low prevalence of germline PALB2 mutations in Australian triple-negative breast cancer.

Triple-negative breast cancer (TNBC) is a tumour classification that is defined by oestrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 receptor negativity. TNBCs share a similar gene expression profile to BRCA-mutated tumours, have been shown to carry a high proportion of BRCA mutations and have a more adverse prognosis compared to other types of breast tumours. PALB2 has been shown to be a moderate-penetrance breast cancer susceptibility gene and is involved in the same DNA damage repair pathway as BRCA1 and BRCA2; this raises the possibility that germline PALB2 mutations may be involved in the pathogenesis of TNBCs. In our study, we sequenced the coding regions of PALB2 (including intron/exon boundaries) in genomic DNA from 347 patients diagnosed with TNBC to determine the prevalence of deleterious mutations in this population. Two novel truncating mutations (c.758dup and c.2390del) and one previously detected truncating mutation (c.3113+5G>C) were found. In addition, five variants predicted to be protein-affecting were also identified. Our study shows that the prevalence of PALB2 germline mutations in individuals with TNBC is ∼1%, similar to the prevalence of PALB2 germline mutation of 1% in familial non-BRCA1/2 breast cancer cohorts.

Familial breast cancer genetic testing in the West of Ireland.

AIMS: The majority of hereditary breast and ovarian cancers are associated with highly penetrant mutations in two genes: BRCA 1 and 2. Our aim was to investigate the prevalence and types of BRCA mutations in patients from the West of Ireland. METHODS: A retrospective cohort study was undertaken that included all patients from the counties, Mayo, Sligo, Galway, Roscommon, and Clare, who were referred to the National Centre for Medical Genetics (NCMG) for testing for mutations in BRCA 1 or 2 between 2000 and 2010. Data including age, symptoms, family history, Manchester score, and test results were recorded and analysed using SPSS. RESULTS: The NCMG received 380 referrals from the Western seaboard, including 148 for diagnostic testing and 232 for predictive evaluation. Sixty-five patients did not attend for assessment. Two hundred and fifty-six patients fulfilled criteria for genetic counselling, which was accepted by 184, of whom 127 proceeded to testing. Predictive tests were more often declined than diagnostic [41 (46 %) vs. 16 (17 %)]. Ten mutations in BRCA 1 were identified in 20 patients (15 families), including Exon 1-23del (3 families); Exon 14-20del (2 families) and E143X (2 families). Six mutations in BRCA 2 were identified in 15 patients (12 families) including 8525delC (n = 2 families) and 8205-1G>C (n = 3 families). Patients with positive results had significantly higher Manchester scores than those with negative tests [median 25.5 (12-48) vs. 20 (8-37), p = 0.042, Mann-Whitney U test]. CONCLUSION: To identify patients with highly penetrant variants, referrals should be made with strict adherence to guidelines. Counselling should be individualised to counteract intrinsic psychological barriers to testing.

Genetic risk transmission in a family affected by familial breast cancer.

Breast Cancer is the most common malignancy among women. Family history is the strongest single predictor of breast cancer risk, and thus great attention has been focused on BRCA1 and BRCA2 genes whose mutations lead to a high risk of developing this disease. Today, only 25% of high- and moderate-risk genes are known, suggesting the importance of the discovery of new risk modifiers. Therefore, the investigation of new polygenic alterations is of great importance, especially if considered high- and moderate-risk variants. In this study, the transmission of BRCA1-2 polymorphisms in association with the transmission of polymorphisms in the genes NUMA1, CCND1, COX11, FGFR2, TNRC9 and SLC4A7 were examined in all members of a family with the BRCA2 c.6447_6448dup mutation. This is the first study about the transmission of high-risk polygenic variants in all members of a family with a strong history of breast cancer. The results about the possible polygenic variant associations that could increase and modify the risk suggested the importance to search new variants to better manage patients and their family members.

BRCA1/2 and clinical outcome in a monoinstitutional cohort of women with hereditary breast cancer.

The clinical outcome of BRCA mutation carriers and non-carriers still remains a topic of discussion. In order to interpret controversial data, in the present study, we analyzed a large consecutive monoinstitutional series of breast cancer patients and relatives with familial features carrying or not carrying BRCA mutations. The intense research in recent years regarding the clinical genetics of patients with breast or ovarian cancer and their relatives has allowed the organization of a unique database comprising anamnestic, clinical, pathological and molecular data. Families with two or more cases of breast cancer under the age of 50 years, or with three cases at any age, were identified. From June, 2003 to June, 2010, a total of 202 patients (136 probands + 66 relatives) from 45 families were included in the analysis. A total of 136 (49 carrier and 87 non-carrier) cases had a cancer diagnosis at the time of their genetic testing. Twenty and 24 events were observed in the carrier and control group, respectively. The 10-year disease-free suvival rate was 57% for patients in the control group compared with 50% for patients carrying a BRCA mutation (P=0.15 by log-rank test). Finally, 66 (32 genetic and 34 control) cases were unaffected at the time of molecular analysis, and 6 new cases of cancer were observed in the carriers, while no new cases were detected in the control cohort. Thus, at age 50, 40% of carriers had a high risk of disease (P=0.0069 by log-rank test). Our data support the hypothesis that the presence of BRCA mutations does not alter the clinical outcome for hereditary breast cancer patients. Conversely, BRCA mutations are proven to be crucial for prediction of risk in healthy relatives from carrier families.

DNA methylation and miRNAs regulation in hereditary breast cancer: epigenetic changes, players in transcriptional and post- transcriptional regulation in hereditary breast cancer.

The genetic alterations associated with breast carcinogenesis are well known. On the contrary epigenetic alterations in hereditary breast cancer are a new field. Two epigenetic mechanisms have emerged as the most critical players in transcriptional regulation in breast cancer: the methylation of DNA and microRNA interference. In this review we will focus on recent findings on gene silencing caused by DNA methylation and microRNA to explore the potential role of these epigenetic changes in the understanding of hereditary breast cancer. Moreover we will describe the same alterations in basal-like breast cancer and in triple-negative breast cancer, since their phenotypes have similarities with BRCA1-mutated tumors. To underline the possibility that some epigenetic alterations could also be used as potential epigenetic biomarkers of drug sensitivity or resistance, we will discuss the more common therapies in hereditary breast cancer that could also be applied to breast cancer with basal-like or triple negative phenotypes.