Expression of Vascular Endothelial Growth Factor and Thrombospondin-1 mRNA Related to Microvessel Density in Invasive Cervical Carcinomas / 대한산부인과학회지

ABSTRACT

OBJECTIVE: Vascular Endothelial Growth Factor (VEGF) is a potent stimulator of angiogenesis in solid tumors. Thrombospondin-1 (TSP-1) has inhibitory role in cancer cell proliferation and metastasis. To analyze the correlation with expression of VEGF and TSP-1 including microvessel density (MVD), the levels of VEGF/TSP-1 mRNA expression and microvessel count (MVC) were estimated in patients with invasive cervical carcinomas. METHODS: From 1996 to 1999, 37 carcinomas and 7 normal cervical tissues were collected, frozen and stored at -70 degrees C until used. The levels of VEGF and TSP-1 mRNAs were determined by quantitative RT-PCR. MVD was assessed by immunostaining for factor VIII-related antigen. The results are expressed as the largest number of microvessels present within a single x 40 field, and counted at x 100 field. RESULTS: Quantitative RT-PCR analysis demonstrated abnormally increased VEGF mRNA expression levels (>0.66) in 14 (37.8%) of 37 cervical carcinomas comparing to control groups (mean 0.32+/-0.09) and abnormally low TSP-1 mRNA expression levels (<0.72) in 13 (35.1%) of 37 cervical carcinomas comparing to control groups (mean 0.51+/-0.07). MVC was higher in tumors showing decreased expression of TSP-1 (but not statistically) (p<0.18) and overexpression of VEGF (p<0.05). When VEGF overexpression was accompanied with reduced TSP-1 expression, the microvessel density showed significantly increased pattern (p<0.05). CONCLUSION: Our study demonstrates that reduced expression of TSP-1 mRNAs and overexpression of VEGF mRNAs may be an important contributing factor in cervical carcinomas. Moreover, the inversed correlation of VEGF and TSP-1 mRNA expression can be an evidence of angiogenic role in cervical carcinomas.