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BRCA1 is a major tumor suppressor that functions in the accurate repair of DNA double-strand breaks via homologous recombination (HR). Nonsense mutations in BRCA1 lead to inactive truncated protein products and are associated with high risk of breast and ovarian cancer. These mutations generate premature termination codons (PTCs). Different studies have shown that aminoglycosides can induce PTC suppression by promoting stop codon readthrough and restoring full-length (FL) protein expression. The use of these compounds has been studied in clinical trials for genetic diseases such as cystic fibrosis and Duchenne muscular dystrophy, with encouraging results. Here we show proof-of-concept data demonstrating that the aminoglycoside G418 can induce BRCA1 PTC readthrough and restore FL protein synthesis and function. We first demonstrate that G418 treatment restores BRCA1 FL protein synthesis in HCC1395, a human breast tumor cell line carrying the R1751X mutation. HCC1395 cells treated with G418 also recover HR DNA repair and restore cell cycle checkpoint activation. A set of naturally occurring BRCA1 nonsense variants encoding different PTCs was evaluated in a GFP C-terminal BRCA1 construct model and BRCA1 PTC readthrough levels vary depending on the stop codon context. Because PTC readthrough could generate FL protein carrying pathogenic missense mutations, variants representing the most probable acquired amino acid substitutions in consequence of readthrough were functionally assessed by a validated transcription activation assay. Overall, this is the first study that evaluates the readthrough of PTC variants with clinical relevance in the breast and ovarian cancer-predisposing gene BRCA1 ., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Abreu, Gomes, Nepomuceno, Li, Fuchshuber-Moraes, De Gregoriis, Suarez-Kurtz, Monteiro and Carvalho.)

Objective: Several algorithms have been proposed to reduce the genotyping effort and cost, while retaining the accuracy of N-acetyltransferase-2 (NAT2) phenotype prediction. Data from the 1000 Genomes (1KG) project and an admixed cohort of Black Brazilians were used to assess the accuracy of NAT2 phenotype prediction using algorithms based on paired single nucleotide polymorphisms (SNPs) (rs1041983 and rs1801280) or a tag SNP (rs1495741)., Methods: NAT2 haplotypes comprising SNPs rs1801279, rs1041983, rs1801280, rs1799929, rs1799930, rs1208 and rs1799931 were assigned according to the arylamine N-acetyltransferases database. Contingency tables were used to visualize the agreement between the NAT2 acetylator phenotypes on the basis of these haplotypes versus phenotypes inferred by the prediction algorithms., Results: The paired and tag SNP algorithms provided more than 96% agreement with the 7-SNP derived phenotypes in Europeans, East Asians, South Asians and Admixed Americans, but discordance of phenotype prediction occurred in 30.2 and 24.8% 1KG Africans and in 14.4 and 18.6% Black Brazilians, respectively. Paired SNP panel misclassification occurs in carriers of NATs haplotypes *13A (282T alone), *12B (282T and 803G), *6B (590A alone) and *14A (191A alone), whereas haplotype *14, defined by the 191A allele, is the major culprit of misclassification by the tag allele., Conclusion: Both the paired SNP and the tag SNP algorithms may be used, with economy of scale, to infer NAT2 acetylator phenotypes, including the ultra-slow phenotype, in European, East Asian, South Asian and American populations represented in the 1KG cohort. Both algorithms, however, perform poorly in populations of predominant African descent, including admixed African-Americans, African Caribbeans and Black Brazilians.

Background: Cervix cancer (CC) represents the fourth most common cancer in women. Treatment involving cisplatin and radiotherapy has been the standard for locally advanced disease. Everolimus inhibits the aberrant activity of mTOR that is part of carcinogenesis in CC. Further everolimus inactivates the HPV E7 oncoprotein and inhibits its proliferation. Preclinical models have suggested that everolimus sensitizes tumoral cells and vasculature to cisplatin and radiotherapy., Methods: In a 3 + 3 design, the trial aimed to treat three dose levels of at least three patients with daily doses of everolimus (2.5, 5 and 10 mg/day), cisplatin and radiotherapy delivered in a 9-week interval in CC patients, stage IIB, IIIA or IIIB. Patients received everolimus from day -7 up to the last day of brachytherapy. Primary objective was to evaluate safety, toxicity and the maximum-tolerated dose (MTD) of everolimus in association with cisplatin and radiotherapy. Pharmacokinetic (PK) parameters and response rates were analyzed as secondary objectives., Results: Thirteen patients were enrolled, 6 at 2.5 mg, 3 at 5 mg and 4 at 10 mg. Four patients did not complete the planned schedule, 1 at 2.5 mg presented grade 4 acute renal failure interpreted as dose-limiting toxicity (DLT) and 3 at 10 mg: 1 with disease progression, and 2 with DLTs-1 grade 3 rash and 1 grade 4 neutropenia. PK results were characterized by dose-dependent increases in AUC and C max., Conclusions: The MTD of everolimus in combination with cisplatin and radiotherapy has been defined as 5 mg/day. The data regarding safety and response rates support further studies.