A common SNP in the UNG gene decreases ovarian cancer risk in BRCA2 mutation carriers

Genetic variations in DNA excision repair pathway contribute to the chemosensitivity and prognosis of acute myeloid leukemia

Acute myeloid leukemia (AML) is a hematologic malignancy with a high recurrence rate and poor long-term prognosis. DNA excision repair systems, such as base excision repair (BER) and nucleotide excision repair (NER), play a major role in maintaining genomic stability and integrity. Further intensive investigations are necessary to uncover additional AML prognosis loci. In this study, we analyzed 16 candidate SNPs within NER and BER pathways in AML patients. Our results showed the GT/GG genotype of the XPC rs2228001 polymorphism was significantly associated with WBC count in dominant models (OR = 0.41, 95 % CI = 0.18-0.96, p = 0.039). Additionally, the rs25487 and rs3213245 SNPs in the XRCC1 gene, in both co-dominant and dominant models, were significantly associated with PLT count in AML (p < 0.05). The GG genotype of rs1130409 in APEX1 was more prone to adverse cytogenetics in both the codominant and recessive models (p < 0.05). Furthermore, the GA genotypes of ERCC8 rs158572 in codominant model was significantly correlated with refractory group (p < 0.05). ERCC8 rs158572 and XRCC1 rs3213245 in both codominant and dominant models were significantly correlated with the MRD positivity (p < 0.05). Kaplan-Meier analysis revealed an link between overall survival (OS) and the co-dominant, dominant, and recessive models of rs2228001 in XPC. Additionally, patients with the GG and GT/GG genotype in the co-dominant, dominant model and recessive model in XPC rs2228001 exhibited significantly longer survival (p < 0.05). Multivariate Cox analyses indicated that rs2228001 in both co-dominant and dominant models were independent favorable factors impacting patient OS (OR < 1). Our findings suggest that genetic polymorphisms in DNA excision repair pathway genetic polymorphisms contribute to the chemosensitivity and prognosis of acute myeloid leukemia.

Gene polymorphisms of METTL5 and METTL16 are related to epithelial ovarian cancer risk in South China: A three-center case-control study

Background: The potential relation of methyltransferase-like gene polymorphisms and epithelial ovarian cancer (EOC) remains unclear. Methods: Five SNPs (METTL5 rs3769767 A>G, METTL16 rs1056321 T>C, METTL5 rs10190853 G>A, METTL5 rs3769768 G>A and METTL16 rs11869256 A>G) of methyltransferase-like genes was selected trough NCBI dbSNP database. Two hundred and eighty-eight cases and 361 controls were enrolled from three hospitals in South China to conduct the case-control study. Genomic DNA was abstracted from peripheral blood and genotyped through a TapMan assay. Stratified analysis was conducted to explore the association of rs10190853, rs3769768, rs11869256 genotype and EOC susceptibility. The combination analysis was adopted to evaluate the relation between inferred haplotypes of the METTL5, METTL16 genes and EOC risk. Multifactor dimensionality reduction (MDR) analysis was performed to verify the interaction of SNPs. Results: Among the five analyzed SNPs, METTL5 rs3769768 AA exhibited a significant association with increased EOC risk, while METTL5 rs10190853 GA, METTL16 rs11869256 GA was certified to decrease the susceptibility of EOC. The stratified analysis further revealed the harmful effect of METTL5 rs3769768 AA in EOC patients. On the contrary, METTL16 rs11869256 AG/GG and METTL5 rs10190853 AA showed the reduced risk of EOC in patients of specific subgroups. Combination analysis identified that haplotypes AAA highly connected with reduced risk of EOC. MDR analysis revealed that these SNPs existed no specific interactions. Conclusion: METTL5 rs3769768 was related to increased risk of EOC. METTL5 rs10190853 and METTL16 rs11869256 decreased the susceptibility in EOC. METTL5 and METTL16 could be potential target of molecular therapy and prognosis markers.

Recommendations for Advancing the Diagnosis and Management of Hereditary Breast and Ovarian Cancer in Brazil

PURPOSE

The objective of this review was to address the barriers limiting access to genetic cancer risk assessment and genetic testing for individuals with suspected hereditary breast and ovarian cancer (HBOC) through a review of the diagnosis and management steps of HBOC.

METHODS

A selected panel of Brazilian experts in fields related to HBOC was provided with a series of relevant questions to address before the multiday conference. During this conference, each narrative was discussed and edited by the entire group, through numerous drafts and rounds of discussion, until a consensus was achieved.

RESULTS

The authors propose specific and realistic recommendations for improving access to early diagnosis, risk management, and cancer care of HBOC specific to Brazil. Moreover, in creating these recommendations, the authors strived to address all the barriers and impediments mentioned in this article.

CONCLUSION

There is a great need to expand hereditary cancer testing and counseling in Brazil, and changing current policies is essential to accomplishing this goal. Increased knowledge and awareness, together with regulatory actions to increase access to this technology, have the potential to improve patient care and prevention and treatment efforts for patients with cancer across the country.

Somatic variants of potential clinical significance in the tumors of BRCA phenocopies

Background

BRCA phenocopies are individuals with the same phenotype (i.e. cancer consistent with Hereditary Breast and Ovarian Cancer syndrome = HBOC) as their affected relatives, but not the same genotype as assessed by blood germline testing (i.e. they do not carry a germline BRCA1 or BRCA2 mutation). There is some evidence of increased risk for HBOC-related cancers in relatives of germline variant carriers even though they themselves test negative for the familial variant (BRCA non-carriers). At this time, BRCA phenocopies are recommended to undergo the same cancer surveillance as individuals in the general population. This raises the question of whether the increased cancer risk in BRCA non-carriers is due to alterations (germline, somatic or epigenetic) in other cancer-associated genes which were not analyzed during BRCA analysis.

Methods

To assess the nature and potential clinical significance of somatic variants in BRCA phenocopy tumors, DNA from BRCA non-carrier tumor tissue was analyzed using next generation sequencing of 572 cancer genes. Tumor diagnoses of the 11 subjects included breast, ovarian, endometrial and primary peritoneal carcinoma. Variants were called using FreeBayes genetic variant detector. Variants were annotated for effect on protein sequence, predicted function, and frequency in different populations from the 1000 genomes project, and presence in variant databases COSMIC and ClinVar using Annovar.

Results

None of the familial BRCA1/2 mutations were found in the tumor samples tested. The most frequently occurring somatic gene variants were ROS1(6/11 cases) and NUP98 (5/11 cases). BRCA2 somatic variants were found in 2/6 BRCA1 phenocopies, but 0/5 BRCA2 phenocopies. Variants of uncertain significance were found in other DNA repair genes (ERCC1, ERCC3, ERCC4, FANCD2, PALB2), one mismatch repair gene (PMS2), a DNA demethylation enzyme (TET2), and two histone modifiers (EZH2, SUZ12).

Conclusions

Although limited by a small sample size, these results support a role of selected somatic variants and epigenetic mechanisms in the development of tumors in BRCA phenocopies.