Wang, C, Sheng, G, Lu, J, Xie, L, Bai, S, Wang, Y et al.. Effect of RNAi-induced down regulation of nuclear factor kappa-B p65 on acute monocytic leukemia THP-1 cells in vitro and vivo. Mol Cell Biochem 359: 125-133

ArticleinMolecular and Cellular Biochemistry 359(1-2):125-33 · September 2011with11 Reads
DOI: 10.1007/s11010-011-1006-z · Source: PubMed
NF-κB p65 is found constitutively active in acute monocytic leukemia, and has been considered an important factor for poor prognosis. Therefore, develop specifically target p65 inhibitors will be substantial interest. Until now, although several p65 inhibitors are currently in preclinical and clinical development, none of them are targeting. In this study, siRNA targeting p65 was introduced into the acute monocytic leukemia cell line THP-1 and THP-1 xenograft tumors in nude mice, and then, we measured p65 mRNA and protein levels by real-time RT-PCR and Western blotting, and levels of related protein cyclin D1, Bc1-2, and SMRT by Western blotting. We also investigated the cell cycle and apoptosis via FCM, and cell proliferation by Cell Counting Kit-8 assay. We found that p65 siRNA could effectively reduce the p65 mRNA and protein expression, arrest cells in G0/G1 phase, inhibit the proliferation and increase the apoptosis of THP-1 cells, and intratumoral injection of p65 siRNA could suppress tumor growth in nude mice. We also found that when down regulation of p65, the expression of cyclin D1 and Bc1-2 decreased, and the expression of SMRT increased in vitro and vivo. All these findings suggest that NF-κB p65 maybe an attractive candidate for the therapeutic targeting of acute monocytic leukemia.
    • "And when they were used in combination with chemotherapy or radiotherapy, synergism could be achieved [9,10,11,12]. Another approach of p65 siRNA transfection has been tried in many types of cancers [15,23,24,25] , and enhanced chemosensitivity was demonstrated as well [15,23]. Yet, combined therapy including p65 siRNA transfection has not been tested in thyroid cancer so far. "
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