FOS-ANKH and FOS-RUNX2 Fusion Genes in Osteoblastoma
CANCER GENOMICS & PROTEOMICS
Authors: Panagopoulos, Ioannis; Gorunova, Ludmila; Lobmaier, Ingvild; Andersen, Kristin; Kostolomov, Ilya; Lund-Iversen, Marius; Bjerkehagen, Bodil; Heim, Sverre
Abstract
Background/Aim: Osteoblastoma is a rare benign tumor of the bones in which recurrent rearrangements of FOS have been found. Our aim was to investigate two osteoblastomas for possible genetic aberrations. Materials and Methods: Cytogenetic, RNA sequencing, and molecular analyses were performed. Results: A FOS-ANKH transcript was found in the first tumor, whereas a FOS-RUNX2 was detected in the second. Exon 4 of FOS fused with sequences either from intron 1 of ANKH or intron 5 of RUNX2. The fusion events introduced a stop codon and removed sequences involved in the regulation of FOS. Conclusion: Rearrangements and fusions of FOS show similarities with those of HMGA2 (a feature of leiomyomas and lipomas) and CSF1 (tenosynovial giant cell tumors). The replacement of a 3'-untranslated region, controlling the gene's expression, by a new sequence is thus a common pathogenetic theme shared by FOS, HMGA2, and CSF1 in many benign connective tissue tumors.
Giant Cell Tumor of Tendon Sheath With a t(1;1)(p13;p34) Chromosomal Translocation
ANTICANCER RESEARCH
Authors: Nakayama, Shizuhide; Nishio, Jun; Nakatani, Kimihiko; Nabeshima, Kazuki; Yamamoto, Takuaki
Abstract
Background: Giant cell tumor of tendon sheath (GCTTS) is a benign soft-tissue tumor that occurs predominantly in the fingers, with the capacity for local recurrence. The cytogenetic hallmark of GCTTS is the presence of 1p13 rearrangement. Several chromosomal segments have been recognized as translocation partners to 1p13. Herein, we describe a novel cytogenetic finding of GCTTS arising in the right thumb of a 71-year-old man. Case Report: Physical examination revealed a 4-cm, elastic hard, immobile, nontender mass. Magnetic resonance imaging demonstrated a nodular mass with reduced signal intensity on both T1- and T2-weighted images. Contrast-enhanced fat-suppressed T1-weighted images showed intense heterogeneous enhancement of the mass. After a needle biopsy, complete excision was performed. Histologically, the tumor was composed of mononuclear cells admixed with multinucleated osteoclast-like giant cells, hemosiderin-laden macrophages, foamy cells, and inflammatory cells. Cytogenetic analysis revealed a reciprocal t(1;1)( p13; p34) translocation as the sole structural aberration. Conclusion: To the best of our knowledge, this is the first report of this tumor with t(1;1)(p13; p34).