When expression patterns of potential Npn-2 ligands in the chick were examined we found that Sema3B and Sema3G [30] are distinctly expressed by cad-7 expressing BC cells (Figure 4a) both at the dorsal root entry zone (DREZ; Figure 4b,b',e,e', red arrows) and the MEP (black arrows). The gene discussed is SEMA3B; the disease is breast cancer.