The mRNA Expression of Various Angiogenesis-Related Genes in Pediatric Sarcomas and Nonmalignant Lesions of Tissue

For better understanding cancer pathogenesis and searching a potential target for antineoplastic therapy, the authors have studied mRNA expression profile in tissues from 39 children with histological confirmed malignant sarcomas and from 23 patients with bone and soft tissue nonmalignant lesions. mRNA levels of Angiogenesis-related genes VEGFA (including isoforms of 121, 165, 189), VEGFC, VEGFR-1, VEGFR-2, VEGFR-3, HIF-1 alpha, TF, TFPI-1, TFPI-2, uPA, PAI-1 in pediatric specimens were examined using quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). uPA, HIF-1 alpha, VEGFR-1, VEGFR-2, VEGFR-3, and VEGFC mRNA levels from nonmalignant tissue were significantly higher than those from cancer tissue. On the other hand, isoform VEGFA121 and VEGFA165 and ratio VEGFA165/189 mRNA levels in cancer were higher in comparison with nonmalignant tissue. There was a strong correlation between VEGFA165 and VEGFA189 mRNA expression levels both in cancer tissue and in nonmalignant tissue. In grade 4 tumors in comparison with grade 2 tumors, there was a reduced VEGFA165/189 ratio. Moreover, TFPI-1 and TFPI-2 mRNA levels were significantly lower in sarcomas than in nonmalignant lesions and TFPI-2 was significantly lower in grade 4 tumors than in grade 2. The present data suggested that mRNA overexpression of angiogenesis-related genes is not a prerogative of malignant tissues. The authors supposed that in pediatric bone and soft tissue pathology, high expression of mRNAs of some angiogenesis-related genes may be associated with inflammation and physiological angiogenesis rather than with the development of a malignant tumor. The authors showed the importance of VEGFA121 and/or VEGFA165 and VEGFA165/189 isoform ratio in pediatric sarcomas neoangiogenesis and TFPI-2 for tumors grade 4.