AIMS: In this study, we aimed to investigate the molecular mechanisms underlying the development of mucoepidermoid carcinoma (MEC). METHODS AND RESULTS: In 31 cases, we examined the MAML2 fusion status using reverse transcriptase-polymerase chain reaction, and HER2 and EGFR status using immunohistochemistry and chromogenic in-situ hybridization. MAML2 fusions were detected in 15 (57.7%) of 26 MECs analysed, including 11 of 16 (68.8%) low-grade, two of four (50%) intermediate-grade and two of six (33.3%) high-grade MECs. HER2 gene amplification and an increased EGFR gene copy number (with balanced chromosome 7 high-polysomy) were each detected in four of 28 (14.3%) MECs analysed. Irrespective of MAML2 fusion status, all seven high-grade MECs had an increased gene copy number of either HER2 or EGFR, in a mutually exclusive manner, whereas such abnormalities were extremely rare in low- and intermediate-grade MEC. CONCLUSIONS: These results suggest that HER2 or EGFR gene abnormality could play an important role in the development of high-grade MEC, and also in the progression from MAML2 fusion-positive low-/intermediate-grade to high-grade in a subset of MEC. Furthermore, we suggest that high-grade MEC comprises a heterogeneous group of tumours in terms of molecular pathogenesis, in particular MAML2 fusion status.
AIMS: In this study, we aimed to investigate the molecular mechanisms underlying the development of mucoepidermoid carcinoma (MEC). METHODS AND RESULTS: In 31 cases, we examined the MAML2 fusion status using reverse transcriptase-polymerase chain reaction, and HER2 and EGFR status using immunohistochemistry and chromogenic in-situ hybridization. MAML2 fusions were detected in 15 (57.7%) of 26 MECs analysed, including 11 of 16 (68.8%) low-grade, two of four (50%) intermediate-grade and two of six (33.3%) high-grade MECs. HER2 gene amplification and an increased EGFR gene copy number (with balanced chromosome 7 high-polysomy) were each detected in four of 28 (14.3%) MECs analysed. Irrespective of MAML2 fusion status, all seven high-grade MECs had an increased gene copy number of either HER2 or EGFR, in a mutually exclusive manner, whereas such abnormalities were extremely rare in low- and intermediate-grade MEC. CONCLUSIONS: These results suggest that HER2 or EGFR gene abnormality could play an important role in the development of high-grade MEC, and also in the progression from MAML2 fusion-positive low-/intermediate-grade to high-grade in a subset of MEC. Furthermore, we suggest that high-grade MEC comprises a heterogeneous group of tumours in terms of molecular pathogenesis, in particular MAML2 fusion status.
Authors: Nicole A Cipriani; Jonathan J Lusardi; James McElherne; Alexander T Pearson; Andrea D Olivas; Carrie Fitzpatrick; Mark W Lingen; Elizabeth A Blair Journal: Am J Surg Pathol Date: 2019-07 Impact factor: 6.394
Authors: Andrés Coca-Pelaz; Juan P Rodrigo; Asterios Triantafyllou; Jennifer L Hunt; Alessandra Rinaldo; Primož Strojan; Missak Haigentz; William M Mendenhall; Robert P Takes; Vincent Vander Poorten; Alfio Ferlito Journal: Eur Arch Otorhinolaryngol Date: 2014-04-26 Impact factor: 2.503
Authors: Kshitij Parag-Sharma; Jason Tasoulas; Adele M Musicant; Carlos H Viesi do Nascimento-Filho; Zhichuan Zhu; Chloe Twomey; Pengda Liu; Rogerio M Castilho; Antonio L Amelio Journal: Oral Oncol Date: 2021-02-11 Impact factor: 5.337