Presence of intermediate filament protein synemin in select sarcomas

Abstract

Synemin, a large intermediate filament protein, is expressed during development in the central and peripheral nervous system as well as in tumors derived from those tissues. It is also abundant in all three types of muscle and more recently has been found in bone. The purpose of this study was to determine whether synemin is present in tumors of soft tissue and myogenic origin, and to semi-quantitate the amount of synemin therein. Using formalin-fixed, paraffin-embedded tissues, it was determined using immunohistochemistry that synemin was present in most sarcomas but was in highest quantities in gastrointestinal stromal cell tumors (GIST) and leiomyosarcomas. Synemin presence in leiomyosarcomas was not unexpected as it is already known to be found in benign smooth muscle. The presence of synemin in GIST was unexpected and may warrant follow up as a diagnostic marker.

Keywords:

• FFPE
• GIST
• gastrointestinal stromal cell tumor
• sarcoma
• synemin
• immunohistochemistry
• image analysis

Acknowledgments

We would like to thank Cindy Lazar, Histology Manager at Methodist University Hospital, for her histology and immunohistochemistry expertise. S. Criswell obtained IRB approval, performed the technical work in sample preparation and drafted the manuscript. T. O’Brien provided pathology interpretation and manuscript editing. O. Skalli provided idea of the study and manuscript editing.