RESUMEN
OBJECTIVE: A key hurdle in broader next-generation sequencing (NGS) biomarker testing access in oncology is the ongoing debate on NGS's cost-effectiveness. We conducted a systematic review of existing evidence of the costs of NGS as a biomarker testing strategy in oncology and developed policy suggestions. METHODS: We searched multiple databases for studies reporting cost comparisons and cost-effectiveness of NGS across oncology indications and geographies between 2017 and 2022, inclusive. Inclusion criteria were established based on indication and type of cost-effectiveness analysis provided. We validated analyses and policy recommendations with 5 payer/policy maker interviews in the United States, Europe, and United Kingdom. RESULTS: Of the 634 identified studies, 29 met inclusion criteria, spanning 12 countries and 6 indications. Cost comparisons of NGS were evaluated using 3 methodologies: (1) comparison of direct testing costs, (2) comparison of holistic testing costs, and (3) comparison of long-term patient outcomes and costs. Targeted panel testing (2-52 genes) was considered cost-effective when 4+ genes were assessed, and larger panels (hundreds of genes) were generally not cost-effective. Holistic analysis demonstrated that NGS reduces turnaround time, healthcare staff requirements, number of hospital visits, and hospital costs. Finally, studies evaluating NGS testing including the cost of targeted therapies generally found the incremental cost-effectiveness ratio to be above common thresholds but highlighted valuable patient benefits. CONCLUSIONS: Current literature supports NGS's cost-effectiveness as an oncology biomarker testing strategy under specific conditions. These findings underscore the need to develop policies to support holistic assessment of NGS to ensure appropriate reimbursement and access.
RESUMEN
Metazoan promoters are enriched in secondary DNA structure-forming motifs, such as G-quadruplexes (G4s). Here we describe 'G4access', an approach to isolate and sequence G4s associated with open chromatin via nuclease digestion. G4access is antibody- and crosslinking-independent and enriches for computationally predicted G4s (pG4s), most of which are confirmed in vitro. Using G4access in human and mouse cells, we identify cell-type-specific G4 enrichment correlated with nucleosome exclusion and promoter transcription. G4access allows measurement of variations in G4 repertoire usage following G4 ligand treatment, HDAC and G4 helicases inhibitors. Applying G4access to cells from reciprocal hybrid mouse crosses suggests a role for G4s in the control of active imprinting regions. Consistently, we also observed that G4access peaks are unmethylated, while methylation at pG4s correlates with nucleosome repositioning on DNA. Overall, our study provides a new tool for studying G4s in cellular dynamics and highlights their association with open chromatin, transcription and their antagonism to DNA methylation.
