biostudies-literatureUnknown18(1)Fisch ASAdenoid Cystic Carcinoma Research Foundation, United States<h4>Purpose</h4>MYB has been shown to play a central role in oncogenesis in a majority of adenoid cystic carcinomas (ACC). Testing for MYB expression via immunohistochemistry (IHC) or testing for the MYB gene fusion by next-generation sequencing (NGS) have become useful tools for the diagnosis of ACC. In addition, detection of MYB expression may have implications for patient management.<h4>Methods</h4>A cohort of 35 ACC cases was identified from the archival pathology files of the Massachusetts General Hospital. Cases were tested for MYB expression using a panel of 4 different commercially available MYB antibodies and scored using a modified Allred system. RNA-based NGS for MYB gene fusion detection was also performed.<h4>Results</h4>Among 4 different MYB antibodies, the sensitivity for MYB detection ranged from 26 to 97%. When a 30% threshold for determination of MYB immunohistochemical positivity was used, the AB_10900735 IHC clone showed the maximum sensitivity (97%). RNA sequencing revealed 19 (54%) cases positive for MYB fusions, and expression analysis derived from the sequencing data confirmed a significant association between MYB expression and fusion status (p = 0.036). Although less sensitive, the AB_778878 MYB clone showed a significant positive association between IHC staining and MYB RNA expression (R² = 0.15, p = 0.023).<h4>Conclusion</h4>The detection of MYB expression using immunohistochemistry varies significantly depending on the antibody used. Comparison with MYB fusion and transcription levels, as determined by NGS, reveals that MYB has a complex relationship between genetic alterations, transcript levels, and protein abundance.Head and neck pathology114https://www.ebi.ac.uk/biostudies/studies/S-EPMC11512985biostudies-literatureComparative Analysis of MYB Expression by Immunohistochemistry and RNA Sequencing in Clinical Gene Fusion Detection in Adenoid Cystic Carcinoma.PMC11512985Faquin WCFarahani AAThierauf JLennerz JKFisch ASIafrate AJfalseComparative Analysis of MYB Expression by Immunohistochemistry and RNA Sequencing in Clinical Gene Fusion Detection in Adenoid Cystic Carcinoma.<h4>Purpose</h4>MYB has been shown to play a central role in oncogenesis in a majority of adenoid cystic carcinomas (ACC). Testing for MYB expression via immunohistochemistry (IHC) or testing for the MYB gene fusion by next-generation sequencing (NGS) have become useful tools for the diagnosis of ACC. In addition, detection of MYB expression may have implications for patient management.<h4>Methods</h4>A cohort of 35 ACC cases was identified from the archival pathology files of the Massachusetts General Hospital. Cases were tested for MYB expression using a panel of 4 different commercially available MYB antibodies and scored using a modified Allred system. RNA-based NGS for MYB gene fusion detection was also performed.<h4>Results</h4>Among 4 different MYB antibodies, the sensitivity for MYB detection ranged from 26 to 97%. When a 30% threshold for determination of MYB immunohistochemical positivity was used, the AB_10900735 IHC clone showed the maximum sensitivity (97%). RNA sequencing revealed 19 (54%) cases positive for MYB fusions, and expression analysis derived from the sequencing data confirmed a significant association between MYB expression and fusion status (p = 0.036). Although less sensitive, the AB_778878 MYB clone showed a significant positive association between IHC staining and MYB RNA expression (R² = 0.15, p = 0.023).<h4>Conclusion</h4>The detection of MYB expression using immunohistochemistry varies significantly depending on the antibody used. Comparison with MYB fusion and transcription levels, as determined by NGS, reveals that MYB has a complex relationship between genetic alterations, transcript levels, and protein abundance.2024-01-01T00:00:00Z2024 Oct2026-05-13T14:47:38.105Z2026-05-13T14:28:48.48ZS-EPMC115129853946083110.1007/s12105-024-01719-1