SEMA3D and neoplasm: In contrast, expression of sema3A did not inhibit tumor development (Fig. 4, A–B), while sema3D which binds to both neuropilins [26], significantly inhibited tumor development from the MDA-MB-435 cells though less potently than sema3G (Fig. 4, C–D) which may be due to the lower expression levels obtained with sema3D in these cells (Fig. 2B).