Diagnostic significance of tight junction associated proteins in meningeal neoplasms

Abstract

Objective To investigate the expression pattern and value of differential diagnosis of tight junction associated proteins in meningioma, hemangiopericytoma (HPC) and solitary fibrous tumor (SFT). Methods Clinicopathologic and immunohistochemical features of 77 meningiomas, in which including 57 WHO Ⅰmeningiomas composed of 10 fibrous (fibroblastic), 10 meningiothelial, 10 transitional (mixed), 10 angiomatous, 10 psammomatous, and 7 microcystic meningiomas, 10 WHO Ⅱ and 10 WHO Ⅲ meningiomas and 10 HPC and 3 SFT were analyzed. Results Eighty ⁃ five point seventy ⁃ one percent positive epithelial membrance antigen (EMA) immunostain was found in meningiomas (66/77), in which the positive rate of WHO Ⅰ meningiomas was 87.72% (50/57), meningiothelial type was the highest (100%), angiomatous and transitional type were the lowest (80%, for all), WHO Ⅱ and WHO Ⅲ meningioma was 90% (9/10) and 70% (7/10), respectively, and negative for HPC and SFT. The immunoreactivity of CD34, Bcl⁃2, S⁃100 protein (S⁃100) was expressed in some different degree in the above meningeal neoplasms. Except for one HPC showed a special performance of negative⁃stained in tumor cells at the central region around the blood vessel and positive⁃stained in tumor cells at the surrounding region, the rest was positive staining for vimentin (Vim). Except for one WHO Ⅲ meningioma was negative, the others were positive for CD99 staining. Ki⁃67 proliferation index increased with the grade in meningiomas and lower in SFT, but higher in HPC. Immunoreactivities of the tight junction associated protein Claudin⁃1, ⁃3, ⁃4 and ⁃7 were 44.16%-57.14% in meningiomas, in which WHO Ⅰmeningiothelial type was the highest, however, negative for HPC and SFT. Zonula occludens⁃1 (ZO⁃1) was highly positive⁃stained in meningiomas, HPC and SFT. Conclusion Positive ⁃ immunostaining of tight junction associated protein Claudin ⁃ 1, ⁃ 3, ⁃ 4 and ⁃ 7 in meningiomas and negative in HPC and SFT suggest that these claudin proteins could be serve as specific markers in the diagnosis and differential diagnosis of meningeal neoplasms. DOI：10.3969/j.issn.1672-6731.2010.02.021