Fig. 2

CD133⁺ lung cancer cells possess the characteristics of lung CSCs. a, b Tumor growth curve. CD133⁺ or CD133⁻ lung cancer cells (2 × 10⁵) were implanted subcutaneously into SCID mice. The tumor volume = (width² × length)/2. Data are expressed as mean ± SD (n = 6). c, d CD133⁺ lung cancer cells produced more tumor spheres compared with CD133⁻ lung cancer cells. Data are expressed as mean ± SD (n = 3). e, f The mRNA level normalized to β-actin analyzed by RT-PCR. Data are expressed as mean ± SD (n = 3). Student’s non-paired t tests were taken to compare the two groups