ABSTRACT
Objective: To investigate the effect of BSO on DAAO/D-Ala system killing K562e cells. Methods: KDFGC cell stably expressing DAAO was obtained by retrovirus transfection. The integration and expression of DAAO gene in KDFGC cells were identified by PCR and in situ hybridization. The killing effects of D-Ala on KDfGC cells treating with Immol/L BSO were observed. Results: PCR and in situ hybridization analysis confirmed integration of DAAO gene in positive clone and expression of it at mRNA level. The IC50 of KDFGC and KDFGC + BSO treating with D-Ala for 24 hours were 10.21 mmol/L and 7.92 mmol/L, respectively. The 95% confidence limits of them were different. Conclusion: BSO can enhance the killing effect of DAAO/D-Ala system on K652e cells.
ABSTRACT
Objective: To construct retroviral vector pLDAAOSN and observe the function of DAAO gene. Methods: With recombinant DNA technology, DAAO cDNA was cloned into retroviral vector (pLDAAOSN). The vector was transfected into ?XNA cells by CaPO4 method, and the DAAO cDNA was transferred by recombinant retroviral vector into leukemia cell line K562. The positive clones were obtained after G418 selection and termed K DAAO. PCR and in situ hybridization were used to identify the integration and expression of DAAO gene in K DAAO. In order to observe the function of DAAO, K DAAO was treated with 50 mm/L D-Ala. Results: Results of plasmid pLDAAOSN digested with KpnⅠ and the sequence determination confirmed pLDAAOSN contains full-length DAAO cDNA. Infectious titer generated by the packaging cells was 5.2?10 6 CFU/ml. PCR and in situ hybridization analysis showed integration of DAAO gene in K DAAO and expression of DAAO gene at mRNA level. Preliminary observation suggested that D-Ala could effectively kill K DAAO. Conclusion: Retroviral vector pLDAAOSN may be useful for futher study of gene therapy in cancer.