In this study, it was observed that the level of VEGF was reduced with reduction of levels of Id1 and Id3 in SCLC in vitro and in vivo (Fig.6C, Fig. 6D, Fig. 5) and that reduced VEGF secreted by transfectant cells was associated with reduction of angiogenesis (Fig. 6F). The gene discussed is ID1; the disease is small cell lung carcinoma.