Detection of Nine Oncogenes Amplification in Lung and Colorectal Cancer Formalin-Fixed Paraffin-Embedded Tissue Samples using Combined Next-Generation Sequencing-Based Script and Digital Droplet Polymerase Chain Reaction

Introduction Gene copy number variations have theranostic impact and require reliable methods for their identification. We aimed to evaluate the reliability of combined next-generation sequencing (NGS) and digital droplet PCR (ddPCR) method for gene amplification evaluation. Methods We conducted a retrospective multicentric observational study. MET/ERBB2 amplifications were assessed in patients with lung or colorectal carcinoma (cohort A), from 2016 to 2020, by fluorescence in situ hybridization (FISH)/immunohistochemistry (IHC), NGS and ddPCR. NGS-based script and ddPCR were then used to detect amplifications of 7 additional oncogenes ( EGFR, KRAS, BRAF, FGFR1, FGFR2, FGFR3, PIK3CA) in a cohort of patients (cohort B). Results 55 patients (9 control, 25 ERBB2- amplified and 21 MET- amplified) out of 3779 patients tested were included in cohort A. Correlation coefficient between NGS-based script and FISH/IHC results were .88 for MET (P < .001) and .89 (P < .001) for ERBB2 . Using a threshold ratio of 1.56 with the NGS-based script, the sensitivity was 100% for both genes and the specificity 69% for MET and 90% for ERBB2 , respectively . With an alternative 1.76 threshold, sensitivity was 94% for MET and 96% for ERBB2 , while specificity was 85% for MET and 90% for ERBB2 . Correlation coefficient between FISH and ddPCR ratio was .90 for MET and .88 for ERBB2 . In both cohorts, NGS-based script and ddPCR results were significantly correlated regarding all genes (P < .001). Conclusion Combined NGS-based script and ddPCR method is reliable and easily feasible for the detection of gene amplifications, providing useful data for guided therapy in cancer

Genotype-Phenotype Relationships in Inheritable Idiopathic Pulmonary Fibrosis: A Greek National Cohort Study

International audienceBackground: Monogenic and polygenic inheritances are evidenced for idiopathic pulmonary fibrosis (IPF). Pathogenic variations in surfactant protein-related genes, telomere-related genes (TRGs), and a single-nucleotide polymorphism in the promoter of MUC5B gene encoding mucin 5B (rs35705950 T risk allele) are reported. This French-Greek collaborative study, Gen-Phen-Re-GreekS in inheritable IPF (iIPF), aimed to investigate genetic components and patients' characteristics in the Greek national IPF cohort with suspected heritability.Patients and methods: 150 patients with familial PF, personal-family extrapulmonary disease suggesting short telomere syndrome, and/or young age IPF were analyzed.Results: MUC5B rs35705950 T risk allele was detected in 103 patients (90 heterozygous, 13 homozygous, allelic frequency of 39%), monoallelic TRG pathogenic variations in 19 patients (8 TERT, 5 TERC, 2 RTEL1, 2 PARN, 1 NOP10, and 1 NHP2), and biallelic ABCA3 pathogenic variations in 3. Overlapping MUC5B rs35705950 T risk allele and TRG pathogenic variations were shown in 11 patients (5 TERT, 3 TERC, 1 PARN, 1 NOP10, and 1 NHP2), MUC5B rs35705950 T risk allele, and biallelic ABCA3 pathogenic variations in 2. In 38 patients, neither MUC5B rs35705950 T risk allele nor TRG pathogenic variations were detectable. Kaplan-Meier curves showed differences in time-to-death (p = 0.025) where patients with MUC5B rs35705950 T risk allele alone or in combination with TRG pathogenic variations presented better prognosis.Conclusion: The Gen-Phen-Re-GreekS in iIPF identified multiple and overlapping genetic components including the rarest, underlying disease's genetic "richesse," complexity and heterogeneity. Time-to-death differences may relate to diverse IPF pathogenetic mechanisms implicating "personalized" medical care driven by genotypes in the near futur

Genotype-Phenotype Relationships in Inheritable Idiopathic Pulmonary Fibrosis: A Greek National Cohort Study

Background: Monogenic and polygenic inheritances are evidenced for idiopathic pulmonary fibrosis (IPF). Pathogenic variations in surfactant protein-related genes, telomere-related genes (TRGs), and a single-nucleotide polymorphism in the promoter of MUC5B gene encoding mucin 5B (rs35705950 T risk allele) are reported. This French-Greek collaborative study, Gen-Phen-Re-GreekS in inheritable IPF (iIPF), aimed to investigate genetic components and patients’ characteristics in the Greek national IPF cohort with suspected heritability. Patients and Methods: 150 patients with familial PF, personal-family extrapulmonary disease suggesting short telomere syndrome, and/or young age IPF were analyzed. Results: MUC5B rs35705950 T risk allele was detected in 103 patients (90 heterozygous, 13 homozygous, allelic frequency of 39%), monoallelic TRG pathogenic variations in 19 patients (8 TERT, 5 TERC, 2 RTEL1, 2 PARN, 1 NOP10, and 1 NHP2), and biallelic ABCA3 pathogenic variations in 3. Overlapping MUC5B rs35705950 T risk allele and TRG pathogenic variations were shown in 11 patients (5 TERT, 3 TERC, 1 PARN, 1 NOP10, and 1 NHP2), MUC5B rs35705950 T risk allele, and biallelic ABCA3 pathogenic variations in 2. In 38 patients, neither MUC5B rs35705950 T risk allele nor TRG pathogenic variations were detectable. Kaplan-Meier curves showed differences in time-to-death (p = 0.025) where patients with MUC5B rs35705950 T risk allele alone or in combination with TRG pathogenic variations presented better prognosis. Conclusion: The Gen-Phen-Re-GreekS in iIPF identified multiple and overlapping genetic components including the rarest, underlying disease’s genetic “richesse,” complexity and heterogeneity. Time-to-death differences may relate to diverse IPF pathogenetic mechanisms implicating “personalized” medical care driven by genotypes in the near future