Background & objective: It was reported that reported that changes of the expression of integrins played critical roles in differentiation, proliferation, and invasion of lung carcinoma, melanoma, and glioma. However, no data was available on the expression of integrins in meningiomas. The aim of this study was to investigate the expression of integrin-alpha 3 in meningiomas and its biological significance.
Methods: Integrin-alpha 3 subunit was detected using in situ hybridization in meningiomas(36 cases), normal dura(2 cases), and arachnoid tissue(3 cases). SABC immunohistochemical assay was used to determine the expressions of Ki-67 nuclear antigen.
Results: Expressions of integrin-alpha 3 mRNA in benign, atypical, and malignant meningiomas were 2.52 +/- 0.362, 1.75 +/- 0.316, and 1.42 +/- 0.633, respectively. The expression levels of integrin-alpha 3 mRNA were significantly lower in the atypical and malignant meningiomas than in the benign meningiomas(P < 0.05, < 0.01). The integrin-alpha 3 mRNA expression in those with invasive biological behavior was lower than that in those without invasion(1.63 +/- 0.462 vs 2.61 +/- 0.526, P < 0.01). Moreover, the expression of integrin-alpha 3 mRNA was inversely associated with Ki-67 labeling index.
Conclusions: Integrin-alpha 3 sub-unit participates the process of regulating growth of meningiomas. The proliferational activity and malignant grade of meningiomas correlates to decreased expression of integrin-alpha 3 subunit, and the down-regulation of integrin-alpha 3 mRNA is associated with the invasive biological behavior in meningiomas.