Melanoma cell migration in vitro can be blocked in a modified Boyden chamber assay using the anti-angiogenic endogenous sister isoform VEGF165b.


Session type:

Daemon Dewing1, Maxine Emmett1, Paul McArthur1, Rowan Pritchard Jones1
1University of Liverpool, Merseyside, United Kingdom


Background: Melanoma is the most lethal skin cancer with 2000 deaths annually in the UK. Angiogenesis, the growth of new blood vessels, is an absolute pre-requisite for tumour growth and metastasis. Central to this process is Vascular Endothelial Growth Factor (VEGF)[1]. The alternative splicing of the VEGF gene results in pro- (eg VEGF165) or anti-angiogenic isoforms (eg VEGF165b) [2]. This latter isoform binds at VEGF-R2 as an equipotent inhibitor of pro-angiogenic VEGF.

VEGF stimulates endothelial cell migration, sprouting of blood vessels and generates new vessel formation within tumours. Significantly, we have demonstrated that VEGF also stimulates melanoma cell migration.


Methods: Using a modified Boyden chamber, migration of metastatic A375 melanoma cells was assessed in response to pro-angiogenic VEGF165 and anti-angiogenic VEGF165b, through a collagen coated porous membrane.


Results: We demonstrated mean ±SEM dose dependent migration of 1.49±0.15 and 10.37±0.94 fold increases over the control, when using VEGF165 at concentrations of 20ng/ml and 160ng/ml respectively (ANOVA p<0.001). Furthermore, this VEGF165 induced migration can be completely blocked using equipotent anti-angiogenic VEGF165b in a dose dependent fashion.


Conclusion: Our data demonstrates, for the first time, not only that tumour cells migrate in a dose dependent manner, and hence potentially metastasise in response to pro-angiogenic VEGF, but that migration is inhibited by endogenous anti-angiogenic VEGF165b in a similarly dose dependent manner. This further supports our endeavor to consider the therapeutic possibilities of this molecule.