Construction of luciferase reporter gene cell model and its application in screening rhein derivatives targeting RAC1 / 中国药理学通报

Aim To establish luciferase reporter gene expression cell models of CNEi-RACI-Luc2 based on the target of RAC1 promoter, and explore the application of screening anti-tumor active of rhein derivatives targeted regulating RAC1 at transcriptional level. Methods The lentiviral carrying luciferase reporter vector was designed and synthesized using RAC1 promoter se-quence, and CNE1 cells were infected with recombinant plasmid lentiviral to obtain cell lines that stably expressed firefly luciferase. Luciferase reporter assay was used to detect the luciferase luminescence value after stimulating with RAC1 activator PMA and inhibitor NSC23766 that targeted regulating the RAC1 promoter activities in cells, and RAC 1 expression was verified by Western blot. The effect of series of rhein derivatives on the lu-cifcrase activity of RAC1 promoter was observed, and RAC1 expression was determined by Western blot. Results The identification result of double enzyme digestion showed that a lentiviral expression vector carrying luciferase reporter vector rc-combined with RAC1 promoter was successfully constructed. Lcntivirus-infcctcd CNE1 cells were screened by puromycin, the CNE1-RAC1-Luc2 cells stably expressing firefly luciferase were obtained, and the Iransfection efficiency was over 90%. The RAC1 luciferase reporter assay system was sensitive to FMA and NSC23766 and consistent with the result of RAC1 protein expression by Western blot. The regulation of series of rhein derivatives to RAC1 luciferase activity of CNE1-RAC1-Luc2 cells was consistent with the results of Western blot. Conclusions The cell model of luciferase reporting system containing RAC1 promoter can be successfully constructed, which provides a practical platform for high throughput screening of RAC1-targeted drugs.

Synthesis and biological evaluation of aminoalcohol rheinate as anti-osteosarcoma agents / 药学学报

Rhein (4,5-dihydroxyanthraquinone-2-carboxylic acid) is the primary anthraquinone in the roots of rhubarb. A recent study showed that rhein can inhibit tumor cell proliferation and induce apoptosis in human tumor cells. However, the clinical application of rhein has been hampered by its poor bioavailability, low aqueous solubility and gastrointestinal disorders. In current study, twenty-four target compounds were designed and synthesized by coupling various hydrophilic alkanolamines to the 2-carboxyl of rhein, and their structures were established by IR, HR-MS, 1H NMR spectra. Solubility test showed that all compounds were 10.04 to 15.08 mg·mL-1 in water, which was 220 to 330-fold better than that of rhein (0.045 6 mg·mL-1). All of rhein derivatives displayed more potent anti-tumor activity than rhein, and most of them were comparable to adriamycin, particularly, compound 4t exhibited IC50 value of 2.08 μmol·L-1, more effective than adriamycin (IC50=2.35 μmol·L-1). Hydroxyapatite adsorption experiment suggests that compound 4t has a better bone affinity than that of tetracycline.