Comparative insight into expression of recombinant human VEGF111b, a newly identified anti-angiogenic isoform, in eukaryotic cell lines

VEGF-A is a critical growth factor in tumor growth and progression. Two families of VEGF-A isoforms are produced through alternative splicing including VEGFxxx pro-angiogenic and VEGFxxxb anti-angiogenic isoforms. VEGF111b is a new member of the VEGFxxxb family that is induced by mitomycin C and doesn't express in normal conditions. The potent anti-angiogenic properties of VEGF-111b and its remarkable resistance to proteolysis make it an interesting alternative candidate for therapeutic use in all types of cancers. Here, the recombinant VEGF-111b cDNA with insertion of intronic sequence was constructed by using a class IIs restriction enzyme-based method. The recombinant pBud-VEGF111b was transfected into CHO dhfr− and HEK 293 cell lines which are currently the standard hosts for the production of candidate therapeutic proteins. Then, the VEGF-111b expression was evaluated in two cell lines using the Real-time PCR. The production of VEGF-111b protein was also investigated here by dot blotting. The VEGF expression was increased about 109 and 185-folds in transfected CHO-dhfr− and HEK 293 cells, respectively, in comparison with the un-transfected cells. Dot blotting approach confirmed that both cell lines have successfully produced the VEGF-111b protein.