Abstract： Objective To define the contents of different stem characteristic subsets in tumor cells based on the high expression of ALDH. Methods We identified the ALDH expression by FCM in cell line cells of Kunming mouse liver cancer H22, gastric cancer BGC-823, colon cancer LS-174T, liver cancer SMMC-7721, pancreatic cancer SW-1990 and Panc-1. We isolated ALDH high , ALDH low and ALDH neg subsets according to the level of ALDH expression in the ALDH+ cells, and analyzed CD133/CD44 and the cell cycle. Results 1. The expression of ALDH in H22,LS-174T, SW-1990 and Panc-1was positive but negative in BGC-823 and SMMC-7721. 2. In H22 cell, ALDH high ，ALDH low and ALDH neg subsets were identified based on the difference of ALDH. 3. The proportion of CD133/CD44 in ALDH high ，ALDH low and ALDH neg subsets of H22 cell decreased. 4. During the observation of H22 cell, ALDH high subset existed in the G 0/G 1 phase, ALDH low subset was mainly in the S phase and ALDH neg subset largely appeared in the G 2/M phase. Conclusions There exists a specific subset between the stem cells and the normal cells in cancer cells, promising a new horizon in cancer treatment.
