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Biology subjects

Puig, O.

Publications and source records attributed to Puig, O..

5 recordsLinked to original sources

Efficient inhibition of cell proliferation and promotion of apoptosis requires continuous treatment with abemaciclib.

Abemaciclib is an oral, selective cyclin-dependent kinase 4 & 6 inhibitor (CDK4 & 6i), approved for hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer (ABC) as monotherapy for endocrine refractory disease, and with endocrine therapy (ET) for initial treatment and after progression on ET. Abemaciclib has also shown clinical activity in combination with ET in patients with high risk early BC (EBC). Here, we examined the preclinical attributes of abemaciclib and other CDK4 & 6i using biochemical and cell-based assays. In vitro, abemaciclib preferentially inhibited CDK4 kinase activity versus CDK6, resulting in inhibition of cell proliferation in a panel of BC cell lines with higher average potency than palbociclib or ribociclib. Abemaciclib showed activity regardless of HER2 amplification and phosphatidylinositol 3-kinase (PI3KCA) gene mutation status. In human bone marrow progenitor cells, abemaciclib showed lower impact on myeloid maturation than other CDK4 & 6i when tested at unbound concentrations similar to those observed in clinical trials. Continuous abemaciclib treatment provided profound inhibition of cell proliferation, and triggered senescence and apoptosis. These preclinical results support the unique efficacy and safety profile of abemaciclib observed in clinical trials.

cell biology↗

Molecular Screening of Familial Hypercholesterolemia in the Icelandic Population

Familial hypercholesterolemia (FH) is a monogenic disease characterized by a lifelong exposure to high LDL-C levels that can lead to early onset coronary heart disease (CHD). The main causes of FH identified to date include loss-of-function mutations in LDLR or APOB, or gain-of-function mutations in PCSK9. Early diagnosis and genetic testing of FH suspects is critical for improved prognosis of affected individuals as lipid lowering treatments are effective in preventing CHD related morbidity and mortality. In the present manuscript, we developed a comprehensive next generation sequencing (NGS) panel which we applied on two different resources of FH in the Icelandic population: 62 subjects from 23 FH families with known or unknown culprit mutations, and a population-based sampling of 315 subjects selected for total cholesterol levels above the 95th percentile cut-point. The application of the NGS panel revealed significant diagnostic yields in identifying pathogenic LDLR mutations in both family and population-based genetic testing.

genetics↗

Comprehensive Genetic Testing for Female and Male Infertility Using Next Generation Sequencing

ObjectiveTo develop a comprehensive genetic test for female and male infertility in support of medical decisions during assisted reproductive technology (ART) protocols.\n\nDesignRetrospective analysis of results from 118 DNA samples with known variants in loci representative of female and male infertility.\n\nInterventions(s)None\n\nMain Outcome Measure(s)Next-Generation Sequencing (NGS) of 87 genes including promoters, 5 and 3 untranslated regions, exons and selected introns. In addition, sex chromosome aneuploidies and Y chromosome microdeletions are analyzed concomitantly using the same panel.\n\nResultsAnalytical accuracy was >99%, with >98% sensitivity for Single Nucleotide Variants (SNVs) and >91% sensitivity for insertions/deletions (indels). Clinical sensitivity was assessed with samples containing variants representative of male and female infertility, and it was 100% for SNVs/indels, CFTR IVS8-5T variants, sex chromosome aneuploidies and Copy Number Variants (CNVs), and >93% for Y chromosome microdeletions. Cost analysis comparing the NGS assay with standard, multiple analysis approach, shows potential savings of $2723 per case. Conclusion: A single, comprehensive, NGS panel can simplify the ordering process for healthcare providers, reduce turnaround time, and lower the overall cost of testing for genetic assessment of infertility in females and males, while maintaining accuracy.

genomics↗

SMN1 and SMN2 Copy Number Determination by droplet digital PCR (ddPCR) based on Extreme Value Theory for Threshold Estimation

Spinal muscular atrophy (SMA) is the most frequent genetic cause of infantile death. Homozygous deletion screening of survival of motor neuron (SMN1) represents the first tier in diagnostic testing. In this work, we adopted and optimized a method to increase the accuracy of SMN1 and SMN2 copy number determination on ddPCR platform. This method, which makes no assumption about the distribution of the fluorescence readouts, was shown to significantly increase accuracy and outperform QuantaSoft software on problematic SMN1 samples.\n\nMethod SummaryIn order to increase the accuracy of SMN1 and SMN2 copy number determination by ddPCR, we adopted and optimized a method based on extreme value theory for threshold estimation. Our method increases total accuracy and improves resolution of problematic samples.

genetics↗

Evaluating genetic ancestry and self-reported ethnicity in the context of carrier screening

BackgroundCurrent professional society guidelines recommend genetic carrier screening be offered on the basis of ethnicity, or when using expanded carrier screening panels, they recommend to compute residual risk based on ethnicity. We investigated the reliability of self-reported ethnicity in 9138 subjects referred to carrier screening. Self-reported ethnicity gathered from test requisition forms and during post-test genetic counseling, and genetic ancestry predicted by a statistical model, were compared for concordance.\n\nResultsWe identified several discrepancies between the two sources of self-reported ethnicity and genetic ancestry. Only 30.3% of individuals who indicated Mediterranean ancestry during consultation self-reported this on requisition forms. Additionally, the proportion of individuals who reported Southeast Asian but were estimated to have a different genetic ancestry was found to depend on the source of self-report. Finally, individuals who reported Latin American demonstrated a high degree of ancestral admixture. As a result, carrier rates and residual risks provided for patient decision-making are impacted if using self-reported ethnicity.\n\nConclusionOur analysis highlights the unreliability of ethnicity classification based on patient self-reports. We recommend the routine use of pan-ethnic carrier screening panels in reproductive medicine. Furthermore, the use of an ancestry model would allow better estimation of carrier rates and residual risks.

genetics↗