Somatic BRCA mutation in high grade epithelial ovarian cancer patients

Aim: To identify the frequency of somatic BRCA mutation in epithelial ovarian cancer (EOC), particularly those with high grade subtypes. Methods: Patients diagnosed with EOC included fallopian tube cancer or peritoneal cancer who had surgery during January 2015 to December 2016 were included. High grade subtypes included high grade serous carcinoma, poorly differentiated endometrioid carcinoma, and clear cell carcinoma. BRCA1 and BRCA2 mutations were tested using DNA extracted from formalin-fixed paraffin embedded block or a fresh tumor specimen then analyzed by next generation sequencing system. Patients who had no germline BRCA mutation in their peripheral blood DNA investigated by bi-directional Sanger sequencing were diagnosed as having somatic BRCA mutation. Results: 36 patients were enrolled; majority of the patients (33patients; 97.2%) had EOC, 1 patient (2.8%) had fallopian tube cancer and 2 patients (5.6%) had peritoneal cancer. 28 patients (77.8%) had high grade serous carcinoma, 6 (16.7%) had poorly differentiated endometrioid carcinoma, and 2 (5.6%) had clear cell carcinoma. BRCA1 mutation was detected in tumor tissues of 2 patients (5.6%). These two patients had high grade serous carcinoma and significant family history of breast and/or ovarian cancers. However, BRCA1 mutations were detected in the peripheral blood in both of them. Conclusion: Only 5.6% of BRCA1 mutation was detected in ovarian tumor tissues, all mutations were found in high grade serous subtype. However, germline BRCA mutation was diagnosed, thus there were no somatic mutations in this study

Identification of Shared Neoantigens in BRCA1-Related Breast Cancer

Personalized neoantigen-based cancer vaccines have been shown to be safe and immunogenic in cancer patients; however, the manufacturing process can be costly and bring about delays in treatment. Using off-the-shelf cancer vaccines targeting shared neoantigens may circumvent these problems. Unique mutational signatures and similar phenotypes found among BRCA1-mutated breast cancer make it an ideal candidate for discovering shared neoantigens within the group. We obtained genome sequencing data of breast cancer samples with or without somatic BRCA1 mutations (BRCA1-positive and BRCA1-negative, respectively) from the three public cancer databases; The Cancer Genome Atlas (TCGA), International Cancer Genome Consortium (ICGC), and Catalogue of Somatic Mutations in Cancer (COSMIC); and from three studies with whole genome/exome sequencing data of samples with germline BRCA1 mutations. Data were analyzed separately within the same database/cohort. We found PIK3CA H1047R, E545K, E542K, and N345K recurrently in BRCA1-negative groups across all databases, whereas recurrent somatic mutations in BRCA1-positive groups were discordant among databases. For germline BRCA1-mutated breast cancer, TP53 R175H was unanimously the most frequent mutation among the three germline cohorts. Our study provides lists of potential shared neoantigens among BRCA1-related breast cancer, which may be used in developing off-the-shelf neoantigen-based vaccines

The association between vitamin D receptor polymorphism and phases of chronic hepatitis B infection in HBV carriers in Thailand

Vitamin D receptor (VDR) polymorphism partly regulates the immune system and is associated with hepatic flare in chronic Hepatitis B virus infection (HBV). Our study identified the association between two distinct phases, VDR polymorphisms and HBV inactive carrier (IC) and chronic hepatitis (CH). Chronic HBV patients were enrolled from February to August 2020. An HBV viral load (VL) < 2,000 IU/ml twice for 6 months apart, with no prior history of HBV treatment, defined the IC phase. Six common polymorphisms in the VDR gene, including CdX-2, GATA, FokI, Bsml, ApaI, and TaqI, were studied using real-time PCR. The different outcomes in allele, genotype, and haplotype frequencies in between groups and linkage disequilibrium (LD) mapping were analyzed. Among 324 enrolled patients, there were 163 patients in IC and 161 patients in CH phases. The mean vitamin D levels were not statistically different between groups. The proportion of allele frequencies of CdX-2 in IC and CH was 53.7% and 62.7% for G allele, and 46.3% and 37.3% for A allele (p 0.019). The proportion of GG genotype of CdX-2 was less frequently found in patients with IC compared to that in patients with CH (27% vs 41%, p 0.028). By multivariate analysis, CdX-2 G/A genotypes were independently associated with IC, with adjusted odd ratio (OR) 1.83 (1.10–3.04), p 0.019. The LD mapping of single nucleotide polymorphisms (SNP) revealed high LD scores in Bsml/ApaI/TaqI (BAT) haplotype in both groups while, CdX-2/GATA and GATA/FokI demonstrated high LD score only in CH group. CdX-2 G/A genotypes were independently associated with IC status in Thai patients with chronic HBV infection. The difference in LD of the CdX-2/GATA and GATA/FokI haplotypes in between groups may represent a non-random selection resulting in the variation of immune control

Intracellular Spread of Rabies Virus Is Reduced in the Paralytic Form of Canine Rabies Compared to the Furious Form.

Studies of the furious and paralytic forms of canine rabies at the early stage of disease have shown a more rapid viral colonization of the cerebral hemispheres in the furious form, as measured by viral antigen within neuronal cell bodies and viral RNA levels. Measurement of cellular processes separate from neuronal cell body provides a visual record of the spread of rabies virus which occurs across synapses. In this study, the amount of rabies viral antigen within cell processes was quantitatively assessed by image analysis in a cohort of naturally rabies infected non-vaccinated dogs (5 furious and 5 paralytic) that were sacrificed shortly after developing illness. Measurements were taken at different levels of the spinal cord, brain stem, and cerebrum. Results were compared to the amount of rabies viral antigen in neuronal cell bodies. Generally, the amount of rabies viral antigen in cell processes decreased in a rostral direction, following the pattern for the amount of rabies viral antigen in neuronal cell bodies and the percentage of involved cell bodies. However, there was a delay in cell process involvement following cell body involvement, consistent with replication occurring in the cell body region and subsequent transport out to cell processes. Greater amounts of antigen were seen in cell processes in dogs with the furious compared to paralytic form, at all anatomic levels examined. This difference was even evident when comparing (1) neurons with similar amounts of antigen, (2) similar percentages of involved neurons, and (3) anatomic levels that showed 100% positive neurons. These findings suggest that intracellular transport of the virus may be slower in the paralytic form, resulting in slower viral propagation. Possible mechanisms might involve host-specific differences in intracellular virus transport. The latter could be cytokine-mediated, since previous studies have documented greater inflammation in the paralytic form

Allele and genotype frequencies of six VDR SNPs including <i>CdX-2</i>, <i>GATA</i>, <i>Fok</i>I, <i>Bsm</i>l, <i>Apa</i>I and <i>Taq</i>I in patients with HBeAg positive (N 62) and negative (N 254).

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Haplotype frequencies of VDR SNPs in HBV inactive carrier and chronic hepatitis phases.

Haplotype frequencies of VDR SNPs in HBV inactive carrier and chronic hepatitis phases.</p

Baseline characteristics of patients with HBV inactive carrier (IC) and chronic hepatitis (CH) phases.

Baseline characteristics of patients with HBV inactive carrier (IC) and chronic hepatitis (CH) phases.</p

Univariate and multivariate regression analysis of factors associated with HBV inactive carrier (IC) phase.

Univariate and multivariate regression analysis of factors associated with HBV inactive carrier (IC) phase.</p