Possible impact of HLA class I and class II on malignancies driven by a single germ-line BRCA1 mutation.

This study provides the first immunogenetic preliminary evidence that specific human leucocyte antigen (HLA) class I and class II alleles and haplotypes may be relevant for BRCA1 c.5263_5264insC driven oncogenesis. Observed HLA associations might have practical implications for establishment of predictive markers for the response to immunotherapies in malignancies driven by this germ-line mutation.

Spectrum and frequencies of BRCA1/2 mutations in Bulgarian high risk breast cancer patients.

BACKGROUND: About 3885 women are diagnosed with breast cancer and 1285 die from the disease each year in Bulgaria. However no genetic testing to identify the mutations in high-risk families has been provided so far. METHODS: We evaluated 200 Bulgarian women with primary invasive breast cancer and with personal/ family history of breast cancer for the presence of unequivocally damaging germline mutations in BRCA1/2 using Sanger sequencing. RESULTS: Of the 200 patients, 39 (19.5 %) carried a disease predisposing mutation, including 28 (14 %) with a BRCA1 mutation and 11 (5.5 %) with a BRCA2 mutation. At BRCA1, 6 different mutations were identified, including 2 frameshifts, 1 nonsense and 1 missense that had been previously reported (c.5030_5033delCTAA, c.5263_5264insC, c.4603G > T, c.181 T > G), and 2 frameshifts, which were novel to this study (c.464delA, c.5397_5403delCCCTTGG). At BRCA2, 7 different frameshift mutations were identified, including 5 previously reported (5851_5854delAGTT, c.5946delT, c.5718_5719delCT, c.7910_7914delCCTTT,c.9098_9099insA) and 2 novel (c.8532_8533delAA, c.9682delA). A BRCA1 mutation was found in 18.4 % of women diagnosed with breast cancer at/or under the age of 40 compared to 11.2 % of women diagnosed at a later age; a BRCA2 mutation was found in 4 % of women diagnosed at/or under the age of 40 compared to 6.5 % of women diagnosed at a later age. A mutation was present in 26.8 % patients with a positive family history and in 14.4 % of women with a negative family history. The most prevalent mutation observed in 22 patients (11 %) was BRCA1 c.5263_5264insC, a known Slavic mutation with founder effect in Eastern European and AJ communities. Other recurrent mutations were BRCA2 c.9098-9099insA (2 %), BRCA1 c.181T > G (1 %) and BRCA2 c.5851_5854delAGTT (1 %). Notably, BRCA1 c.5263_5264insC represented 56 % of all mutations identified in this series. Of the 22 patients with BRCA1 c.5263_5264insC, 9 were diagnosed with early onset breast cancer, 11 with TNBCs, 4 with bilateral breast cancer, and 6 with both breast and ovarian cancer. CONCLUSIONS: This is the first comprehensive study of the BRCA1/2 mutation spectrum in Bulgaria and will assist the establishment of efficient protocols for genetic testing and individualized risk assessment for Bulgarian breast/ovarian cancer patients and healthy individuals at a high-risk.

Increased gene expression of TIMP1 and CHI3L1 in fine-needle aspiration biopsy samples from papillary thyroid cancer as compared to benign nodules.

BACKGROUND: Thyroid nodules are common ultrasound findings with malignancy rate 7%-15%. Our objective was to assess the relative expression of the tissue inhibitor of metalloproteinase-1 gene (TIMP1) and chitinase-3-like protein 1 gene (CHI3L1) in fine-needle aspiration biopsy (FNAB) washouts and the serum levels of their protein products (TIMP-1 and chitinase-3-like protein 1 known as YKL-40) in patients with papillary thyroid cancer (PTC) and patients with benign nodules. Furthermore, the correlation between gene expression and circulating protein product was evaluated. METHODS: Eighty patients who underwent FNAB in one tertiary center were recruited in the study. Forty with Bethesda V and VI nodules were operated and PTC was confirmed. The other 40 patients were with Bethesda II nodules. TIMP-1 and YKL-40 serum levels were measured in all subjects. The TIMP1 and CHI3L1 expression was assessed in FNAB washouts from 20 PTC patients and 20 benign cases using quantitative PCR. RESULTS: The relative expression of TIMP1 and CHI3L1 was significantly higher in the PTC group than in the benign group (p < .001 for TIMP1; p = .018 for CHI3L1). The PTC patients had higher serum TIMP-1 than the patients with benign nodules (p = .036). We did not find significant difference in the YKL-40 level between the two groups. TIMP1 and CHI3L1 expression did not correlate with the serum levels of their protein products. CONCLUSION: FNAB washouts could be used for identification of diagnostic markers. The increased TIMP1 and CHI3L1 expression implies a role of these genes in the PTC carcinogenesis.

XRCC1 variants do not represent a risk for dermatomyositis and systemic lupus erythematosus in Bulgarian patients.

INTRODUCTION: Systemic lupus erythematosus (SLE) and dermatomyositis (DM) share a similar pathogenesis, and genetic, hormonal, and environmental factors are known to trigger the autoimmune process. The X-ray repair cross-complementing genes (XRCC1 and XRCC3) are known to play a central role in mammalian DNA repair processes. Evidence suggests that impaired DNA repair efficiency is implicated in the development of autoimmune diseases. This case-control study investigates the association between the XRCC1 Arg194Trp (C>T) and Arg399Gln (G>A) polymorphisms and the susceptibility to DM and SLE in Bulgarian patients. METHODS: Altogether 88 patients, 55 with SLE and 33 with DM, and 94 unrelated healthy controls were included in this study. RESULTS: None of the polymorphisms showed an association with SLE, DM, or their clinical parameters. The allele and genotype frequency of the two single nucleotide polymorphisms was similar to those found in other healthy Caucasian populations. CONCLUSIONS: Our results indicate that the XRCC1 rs1799782 Arg194Trp and rs25487 Arg399Gln polymorphisms do not play a role in the susceptibility to SLE and DM.

Validation of an NGS Approach for Diagnostic BRCA1/BRCA2 Mutation Testing.

BACKGROUND AND OBJECTIVE: Pathogenic mutations in BRCA1/2 tumor suppressor genes increase the lifetime risk for developing breast and ovarian cancer. The aim of the present study was to evaluate the sensitivity and specificity of the Ion Torrent PGM™ for diagnostic mutation screening of BRCA1/2 genes. METHODS: In the current study we included a cohort of 58 Bulgarian high-risk breast cancer patients to validate a next-generation sequencing approach for diagnostic mutation screening of the BRCA1/2 genes using the Ion Torrent Personal Genome Machine® (PGM™) platform. We have also optimized the workflow by comparing two different library preparation methods and using three software packages: NextGENE, Torrent Suite variantCaller, and Samtools/BCFtools to achieve detection of all variants with high specificity and sensitivity. RESULTS: We have validated a quick and accurate diagnostic test, with an overall specificity of 95.9% and sensitivity of up to 100%, which can be the first method of choice, followed by confirmation of the identified variants by Sanger sequencing. Our results prove that the Ion AmpliSeq™ BRCA1/2 Community Panel used with the PGM™ platform, and coupled with our variant selection pipeline, is able to detect all sequence variants discovered by Sanger sequencing. CONCLUSION: The application of the new test which outperforms the classical approach in turn-around time and price will have great impact in the clinical practice to identify the mutation carriers and guide the better personalized treatment of the patients, as well as to contribute for the improved prophylaxis in hereditary breast and ovarian cancer families.

Association of TNF-α polymorphisms with adult dermatomyositis and systemic lupus erythematosus in Bulgarian patients.

BACKGROUND: Single-nucleotide polymorphisms (SNPs) of tumor necrosis factor-alpha (TNF-α) have been implicated in various autoimmune diseases; however, the results are quite controversial, and there is still no widely accepted opinion about their role in the pathology of the autoimmune diseases. This is a pilot study to investigate the association of six SNPs of the TNF-α gene with the risk of adult dermatomyositis (DM) and systemic lupus erythematosus (SLE) in Bulgarian patients. MATERIALS AND METHODS: Twenty-seven patients with DM and 27 with SLE were included in this study. Genomic DNA was extracted from the peripheral blood, and six SNPs (-1031T/C, -863C/A, -857C/T, -308G/A, -238G/A, +489G/A) were selected for investigation by polymerase chain reaction-restriction fragment length polymorphism analysis. RESULTS: We found association between the TNF-α-1031CC genotype and SLE (P = 0.025) and tendency for association with DM (P = 0.0876). The association appeared even stronger in the female patients with SLE (P = 0.024) and DM (P = 0.067). The TNF-α-857GG genotype shows weak association with SLE (P = 0.097, OR 2.06, 95% CI 0.81-5.29) when analyzed for the whole group, but it appeared significantly associated with SLE in women (P = 0.048, OR 3.23, 95% CI 0.93-11.14). The -863C allele showed association with arthritis in patients with SLE (P = 0.008). The haplotype analysis revealed a significant association between TNF -1031C/-863C/-857C/-308G/+489G haplotype with both DM (P = 0.022) and SLE (P = 0.007) in women. CONCLUSIONS: The TNF-α polymorphisms are associated with increased relative risk mainly for SLE, particularly in women, while their role for DM is less evident and needs further analysis in an enlarged sample cohort.