Small heat-shock protein is expressed in meningiomas and in granulofilamentous inclusion bodies

FF cellular expression of estrogen receptor-related small heat-shock protein (HSP27) in meningiomas was investigated immunologically. A cytoplasmic distribution of HSP27 was demonstrated in surgical specimens of 22 of 26 cases with meningiomas and cultured meningioma cells derived from two individuals. By Western blotting, HSP27 was detected in every tissue homogenate of 17 cases studied. Thus, HSP27 appears to be constitutively expressed in most meningiomas. In anaplastic portions of one papillary meningioma, there were numerous granulofilamentous inclusion bodies [Goldman JE et al. (1980) Cancer 46:156-161]. The inclusion bodies were immunopositive for HSP27 despite the negativity of the tumor cytoplasms. Thus, HSP27 seems to participate in the formation of certain inclusion bodies in meningioma cells, like alpha B-crystallin which participates in the formation of Rosenthal fibers in astrocytes.