Thyroid cancer is the most common form of solid neoplasms known to be associated with radiation exposure. However, the mechanisms of radiation-induced carcinogenesis are not well understood. The high prevalence of rearrangements of the RET gene has been recently found in post-Chernobyl papillary thyroid carcinomas and in thyroid tumors from patients exposed to therapeutic external radiation. The positions of breakpoints sites in the RET and ELEI genes identified in post-Chemobyl tumors with RETPTC3 rearrangements suggested that these two genes may be aligned across from each other in the nucleus at the time of DNA breaks (Nikiforov et al., Oncogene, 1999). Consistent with this idea, we found that one pair of RET and H4 genes (contributing to RET/PTCI rearrangement) was juxtaposed in 35 percent of inter-phase nuclei of normal thyroid cells. These data suggest that two potentially recombinogenic chromosomal loci may be contiguous to each other in the nucleus predisposing to generation of rearrangement by adjacent double-strand DNA breaks produced by ionizing radiation or other genotoxic agents. The main goal of the current proposal is to explore the role of nuclear architecture and gene proximity in generation of chromosomal rearrangements after radiation exposure. We propose to use two-color FISH and three-dimensional confocal laser-scanning microscopy to determine the frequency of physical proximity of genes, contributing to the major types of RET/PTC rearrangements, in normal human thyroid follicular cells and in other cell lineages. We will establish whether chromosomal organization with respect to these loci is cell-type specific, age-dependent, or varies with cell cycle stage. Any of these parameters could explain in part the high prevalence of thyroid cancer after irradiation, and the higher susceptibility of children. Then, we will expose cultured cells to different doses of ionizing radiation to test directly the relationship between gene proximity and the frequency of radiation-induced RET/PTC rearrangements in vitro. These studies will extend our understanding of the mechanisms of radiation-induced carcinogenesis in the thyroid gland. In addition, they are likely to have importance for a broad range of chromosomal rearrangements found in cancer.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA088041-03
Application #
6608213
Study Section
Endocrinology Study Section (END)
Program Officer
Pelroy, Richard
Project Start
2001-07-01
Project End
2006-06-30
Budget Start
2003-07-01
Budget End
2004-06-30
Support Year
3
Fiscal Year
2003
Total Cost
$313,994
Indirect Cost
Name
University of Cincinnati
Department
Pathology
Type
Schools of Medicine
DUNS #
041064767
City
Cincinnati
State
OH
Country
United States
Zip Code
45221
Evdokimova, Viktoria N; Gandhi, Manoj; Nikitski, Alyaksandr V et al. (2018) Nuclear myosin/actin-motored contact between homologous chromosomes is initiated by ATM kinase and homology-directed repair proteins at double-strand DNA breaks to suppress chromosome rearrangements. Oncotarget 9:13612-13622
Efanov, Alexey A; Brenner, Alina V; Bogdanova, Tetiana I et al. (2018) Investigation of the Relationship Between Radiation Dose and Gene Mutations and Fusions in Post-Chernobyl Thyroid Cancer. J Natl Cancer Inst 110:371-378
Panebianco, Federica; Kelly, Lindsey M; Liu, Pengyuan et al. (2017) THADA fusion is a mechanism of IGF2BP3 activation and IGF1R signaling in thyroid cancer. Proc Natl Acad Sci U S A 114:2307-2312
Seethala, Raja R; Chiosea, Simion I; Liu, Cheng Z et al. (2017) Clinical and Morphologic Features of ETV6-NTRK3 Translocated Papillary Thyroid Carcinoma in an Adult Population Without Radiation Exposure. Am J Surg Pathol 41:446-457
Picarsic, Jennifer L; Buryk, Melissa A; Ozolek, John et al. (2016) Molecular Characterization of Sporadic Pediatric Thyroid Carcinoma with the DNA/RNA ThyroSeq v2 Next-Generation Sequencing Assay. Pediatr Dev Pathol 19:115-22
Karunamurthy, Arivarasan; Panebianco, Federica; J Hsiao, Susan et al. (2016) Prevalence and phenotypic correlations of EIF1AX mutations in thyroid nodules. Endocr Relat Cancer 23:295-301
Bogdanova, Tetiana I; Zurnadzhy, Liudmyla Yu; Nikiforov, Yuri E et al. (2015) Histopathological features of papillary thyroid carcinomas detected during four screening examinations of a Ukrainian-American cohort. Br J Cancer 113:1556-64
Dettmer, Matthias S; Perren, Aurel; Moch, Holger et al. (2014) MicroRNA profile of poorly differentiated thyroid carcinomas: new diagnostic and prognostic insights. J Mol Endocrinol 52:181-9
Leeman-Neill, Rebecca J; Kelly, Lindsey M; Liu, Pengyuan et al. (2014) ETV6-NTRK3 is a common chromosomal rearrangement in radiation-associated thyroid cancer. Cancer 120:799-807
Armstrong, Michaele J; Yang, Huaitao; Yip, Linwah et al. (2014) PAX8/PPAR? rearrangement in thyroid nodules predicts follicular-pattern carcinomas, in particular the encapsulated follicular variant of papillary carcinoma. Thyroid 24:1369-74

Showing the most recent 10 out of 52 publications