Correlation of MMP-9 and FLT-1 expression with microvessel density in astrocytoma

Purpose To investigate the expression of MMP-9 and Flt-1 in different types of astrocytoma, and their correlation with microvessel density (MVD), and the malignant behaviors of astrocytoma. Methods Immunohistochemical method was used to detect the expression of CD34, MMP-9 and Flt-1 in 50 cases of astrocytoma. MVD was determined according to CD34 immunostaining. Results The expression of MMP-9 and Flt-1 in various degrees was observed in different types of astrocytoma; in different histologic types, obvious difference existed in the expression and its intensity. Grades Ⅲ~Ⅳ astrocytomas of the WHO classification, positive expression of MMP-9 was (76.52±3.38)%, that of Flt-1 was (72.90±2.64)%, and MVD was 87.00±4.18; Grades Ⅰ~Ⅱ astrocytoma, positive expression of MMP-9 was (27.90±2.53)%, that of Flt-1 was (29.67±2.87)%, and MVD was 48.62±4.05. The positive expression of MMP-9 and Flt-1 and MVD in grades Ⅲ~Ⅳ tumours were significantly higher than grades Ⅰ~Ⅱ tumous (P0.01). The expression of MMP-9 and Flt-1 had positively correlated with MVD in astrocytoma. Conclusions MVD and MMP-9 and Flt-1 expression are positively correlated with the grade of astrocytoma and its malignant degree, and probably assistant markers in the evaluation of malignant behaviors and prognosis.