Fig. 2G shows that YPK2-SortLm expressed a higher ratio of CD44v than YPK2-Lm and YPK2. The ratio of CD44v in YPK2 was only 0.2%; however, this ratio in YPK2-Lm and YPK2-SortLm was 16.7 and 99.8%, respectively. Expression of CD44v in YPK5-SortLm was also high compared to YPK5 (Fig. 2H). When NSF-1 or LIF was omitted from CSC-inducing media, CD24low/CD44low cells were dominant; these cells were also dominant in parent cancer cells (Fig. 2I and J). The gene discussed is LIF; the disease is cancer.