Table 2. Primers for semi-quantitative RT-PCR.

Genes	Forward primer sequence	Reverse primer sequence
Dll4	5′-GCTGGAAGTGGATTGTGG-3′	5′-CTTGTCGCTGTGAGGATAC-3′
VEGF	5′- AGCCCATGAAGTGGTGAA -3′	5′- TGCGGATCTTGGACAAAC -3′
β-Actin	5′-CACCCGCGAGTACAACCTTC -3′	5′-CCCATACCCACCATCACACC -3′