1. Somatic mutation signatures in primary liver tumors of workers exposed to ionizing radiation
- Author
-
Jan Blancato, Garrett T. Graham, Islam, David S. Goerlitz, Valentina Revina, Archana Ramesh, Christopher A. Loffredo, Evgeniya Kirillova, Jay Zeck, and Bhaskar Kallakury
- Subjects
Male ,Carcinoma, Hepatocellular ,Neoplasms, Radiation-Induced ,Angiogenesis ,DNA Mutational Analysis ,Hemangiosarcoma ,lcsh:Medicine ,Pilot Projects ,Biology ,Chromatin remodeling ,Article ,Russia ,Cholangiocarcinoma ,Cohort Studies ,03 medical and health sciences ,0302 clinical medicine ,Germline mutation ,Occupational Exposure ,Exome Sequencing ,medicine ,Cancer genomics ,Humans ,lcsh:Science ,Protein kinase B ,Gene ,Exome sequencing ,030304 developmental biology ,Aged ,0303 health sciences ,Multidisciplinary ,lcsh:R ,Liver Neoplasms ,Wnt signaling pathway ,Middle Aged ,medicine.disease ,3. Good health ,Occupational Diseases ,Waste Disposal Facilities ,Liver ,030220 oncology & carcinogenesis ,Radioactive Waste ,Mutation ,Cancer research ,lcsh:Q ,Female ,Liver cancer - Abstract
Liver cancer is associated with genetic mutations caused by environmental exposures, including occupational exposure to alpha radiation emitted by plutonium. We used whole exome sequencing (WES) to characterize somatic mutations in 3 histologically distinct primary liver tumors (angiosarcoma of the liver (ASL), cholangiocarcinoma (CCA) and hepatocellular carcinoma (HCC)) from Mayak worker subjects occupationally exposed to ionizing radiation (IR) to investigate the contribution of IR to the mutational landscape of liver cancer. DNA sequence analysis revealed these tumors harbor an excess of deletions, with a deletions:substitutions ratio similar to that previously reported in radiation-associated tumors. These tumors were also enriched for clustered mutations, a signature of radiation exposure. Multiple tumors displayed similarities in abrogated gene pathways including actin cytoskeletal signaling and DNA double-strand break (DSB) repair. WES identified novel candidate driver genes in ASL involved in angiogenesis and PIK3CA/AKT/mTOR signaling. We confirmed known driver genes of CCA, and identified candidate driver genes involved in chromatin remodeling. In HCC tumors we validated known driver genes, and identified novel putative driver genes involved in Wnt/β-catenin signaling, chromatin remodeling, PIK3CA/AKT/mTOR signaling, and angiogenesis. This pilot study identifies several novel candidate driver mutations that are likely to be caused by IR exposure, and provides the first data on the mutational landscape of liver cancer after IR exposure.
- Published
- 2018