A Comparative Analysis of Tumors and Plasma Circulating Tumor DNA in 145 Advanced Cancer Patients Annotated by 3 Core

Kristian Larson1, Radhamani Kannaiyan2, Ritu Pandey3

  • 1University of Arizona College of Medicine, 1501 N Campbell Ave, Tucson, AZ 85724, USA.

Cancers
|March 20, 2020
PubMed

Insights

This study categorizes gene mutations from next-generation sequencing (NGS) into cell fate, cell survival, and genome maintenance processes. Cell survival mutations were most common, offering insights for advanced cancer treatment strategies.

Area of Science:

  • Genomics and Bioinformatics
  • Cancer Biology
  • Precision Medicine

Background:

  • Targeted and immune checkpoint therapies have advanced cancer treatment, yet tumor heterogeneity causes drug resistance.
  • Understanding complex biological interactions through gene mutation analysis is crucial for guiding effective cancer therapies.

Purpose of the Study:

  • To categorize gene mutations identified via next-generation sequencing (NGS) into three core biological processes: cell fate (CF), cell survival (CS), and genome maintenance (GM).
  • To compare mutation concordance and discordance between tissue (Caris MI/X) and plasma-based (Guardant360) NGS platforms.
  • To identify actionable gene alterations and analyze trends in TP53 mutations and PD-L1 expression in advanced cancer patients.

Main Methods:

  • Collected NGS data from 145 advanced cancer patients who had previously failed standard therapy.
  • Utilized both Caris MI/X (tissue) and Guardant360 (plasma cell-free circulating tumor DNA) platforms for 142 patients.
  • Categorized mutated genes into CF, CS, and GM; performed comparative analysis for concordance, discordance, unclassified mutations, TP53 alterations, and PD-L1 expression.

Main Results:

  • Mutated genes were predominantly categorized under the Cell Survival (CS) process, with higher concordance observed for Guardant360 (64.4%) compared to Caris (51.5%).
  • TP53 alterations represented a significant fraction of mutations across both platforms (Caris: 14.7%, Guardant360: 13.1%).
  • Twenty-six potentially actionable gene alterations were identified by matching circulating tumor DNA (ctDNA) data with unclassified Caris alterations.

Conclusions:

  • The Cell Survival (CS) core cellular process was the most prevalent category of gene mutations in the study population.
  • The findings highlight the potential of ctDNA analysis and categorized mutation data in identifying actionable targets.
  • Further clinical trials are recommended to validate these three core cellular processes as biomarkers for optimizing treatment strategies in advanced cancer.