Figure 3.

Immunoblot of tumor lysates for VEGF. Tumors were grown either s.c. or in the brain. Twenty μg of protein were resolved on a nonreducing 10% polyacrylamide gel, transferred to nitrocellulose, and blotted as described in Materials and Methods. The VEGF:CHO tumors (VEGF) always had the most VEGF, whereas the glioblastomas (U87 and U251) generated the least amount of immunodetectible VEGF. Location minimally affected the amount of VEGF in these tumors. The ∼30-kd band in the U251 i.c. lane may be a VEGF monomer, given that RT-PCR determined that VEGF 121 and 189 were not substantially produced by any tumor. This band was variably present in other samples of tumor lysates.