Establishment of a human colorectal cancer cell line P6C with stem cell properties and resistance to chemotherapeutic drugs
Abstract
Guan-hua RAO2, #, Hong-min LIU3, #, Bao-wei LI1, Jia-jie HAO4, Yan-lei YANG1, Ming-rong WANG4, Xiao-hui WANG1, Jun WANG1, Hai-jing JIN1, Lei DU1, *, Quan CHEN1, *
1State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; 2Tianjin Key Laboratory of Protein Sciences, College of Life Sciences, Nankai University, Tianjin 300071, China; 3Pathogenic Microbiology Laboratory, Biomedical Science, Hebei United University, Tangshan 063000, China; 4State Key Laboratory of Molecular Oncology, Cancer Institute/Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100021, China
Aim: Cancer stem cells have the capacity to initiate and sustain tumor growth. In this study, we established a CD44+ colorectal cancer stem cell line with particular emphasis on its self-renewal capacity, enhanced tumor initiation and drug resistance.
Methods: Fresh colon cancer and paired normal colon tissues were collected from 13 patients who had not received chemotherapy or radiotherapy prior to surgery. Among the 6 single-cell derived clones, only the P6C cell line was cultured for more than 20 passages in serial culture and formed holoclones with high efficiency, and then the stemness gene expression, colony formation, tumorigenicity and drug sensitivities of the P6C cell line were examined.
Results: Stemness proteins, including c-Myc, Oct3/4, Nanog, Lgr5, and SOX2, were highly expressed in the P6C cell line. Oct3/4-positive P6C cells mostly generated holoclones through symmetric division, while a small number of P6C cells generated meroclones through asymmetric division. P6C cells stably expressed CD44 and possessed a high capacity to form tumor spheres. A single cell-derived sphere was capable of generating xenograft tumors in nude mice. Compared to SW480 and HCT116 colorectal cancer cells, P6C cells were highly resistant to Camptothecin and 5-fluorouracil, the commonly used chemotherapeutic agents to treat colorectal cancers.
Conclusion: We established a colorectal cancer stem cell line P6C with a high tumorigenic capacity and the characteristics of normal stem cells. It will benefit the mechanistic studies on cancer stem cells and the development of drugs that specifically target the cancer stem cells.
Keywords: colorectal cancer; cancer stem cell; Oct3/4; self-renewal; CD44 antigens; drug resistance; Camptothecin; 5-fluorouracil
This study was supported by grants from the “Strategic Priority Research Program” of the Chinese Academy of Sciences (Grant No XDA01020105), the 973 program of China (2011CBA01101) and the 863 program of China (2011AA020108).
# These authors contributed equally to this work.
* To whom correspondence should be addressed.
E-mail chenq@ioz.ac.cn (Quan CHEN); dul@ioz.ac.cn (Lei DU)
Received 2013-02-06 Accepted 2013-04-12
Keywords:
1State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China; 2Tianjin Key Laboratory of Protein Sciences, College of Life Sciences, Nankai University, Tianjin 300071, China; 3Pathogenic Microbiology Laboratory, Biomedical Science, Hebei United University, Tangshan 063000, China; 4State Key Laboratory of Molecular Oncology, Cancer Institute/Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100021, China
Aim: Cancer stem cells have the capacity to initiate and sustain tumor growth. In this study, we established a CD44+ colorectal cancer stem cell line with particular emphasis on its self-renewal capacity, enhanced tumor initiation and drug resistance.
Methods: Fresh colon cancer and paired normal colon tissues were collected from 13 patients who had not received chemotherapy or radiotherapy prior to surgery. Among the 6 single-cell derived clones, only the P6C cell line was cultured for more than 20 passages in serial culture and formed holoclones with high efficiency, and then the stemness gene expression, colony formation, tumorigenicity and drug sensitivities of the P6C cell line were examined.
Results: Stemness proteins, including c-Myc, Oct3/4, Nanog, Lgr5, and SOX2, were highly expressed in the P6C cell line. Oct3/4-positive P6C cells mostly generated holoclones through symmetric division, while a small number of P6C cells generated meroclones through asymmetric division. P6C cells stably expressed CD44 and possessed a high capacity to form tumor spheres. A single cell-derived sphere was capable of generating xenograft tumors in nude mice. Compared to SW480 and HCT116 colorectal cancer cells, P6C cells were highly resistant to Camptothecin and 5-fluorouracil, the commonly used chemotherapeutic agents to treat colorectal cancers.
Conclusion: We established a colorectal cancer stem cell line P6C with a high tumorigenic capacity and the characteristics of normal stem cells. It will benefit the mechanistic studies on cancer stem cells and the development of drugs that specifically target the cancer stem cells.
Keywords: colorectal cancer; cancer stem cell; Oct3/4; self-renewal; CD44 antigens; drug resistance; Camptothecin; 5-fluorouracil
This study was supported by grants from the “Strategic Priority Research Program” of the Chinese Academy of Sciences (Grant No XDA01020105), the 973 program of China (2011CBA01101) and the 863 program of China (2011AA020108).
# These authors contributed equally to this work.
* To whom correspondence should be addressed.
E-mail chenq@ioz.ac.cn (Quan CHEN); dul@ioz.ac.cn (Lei DU)
Received 2013-02-06 Accepted 2013-04-12