RK-33

• CAT Number: I009052
• CAS Number: 1070773-09-9
• Molecular Formula: C23H20N6O3
• Molecular Weight: 428.44
• Purity: ≥95%
• Synonyms: 5,11-bis[(4-methoxyphenyl)methyl]-3,5,7,9,11,13-hexazatricyclo[8.3.0.02,6]trideca-1(10),2,6,8,12-pentaen-4-one
• InChI: InChI=1S/C23H20N6O3/c1-31-17-7-3-15(4-8-17)11-28-14-26-19-20-22(25-13-24-21(19)28)29(23(30)27-20)12-16-5-9-18(32-2)10-6-16/h3-10,13-14H,11-12H2,1-2H3
• InChIKey: COUMZXFUZDBRCZ-UHFFFAOYSA-N
• SMILES: COC1=CC=C(C=C1)CN2C=NC3=C2N=CN=C4C3=NC(=O)N4CC5=CC=C(C=C5)OC

RK-33 is an RNA helicase inhibitor against DDX3, and inhibits its helicase activity.
RK-33 shows inhibition of many kinds of cancer cells with IC50 of 3-6 µM, while PC3 is much less sensitive to RK-33 (IC50 >12 µM). RK-33 treatment causes a significant accumulation in the G1 phase for DU145 and LNCaP, although treatment with RK-33 causes only a moderate accumulation of the G1 phase for 22Rv1, and the treated cells have significantly reduced G2 phase. RK-33 treatment also causes 12 moderate G1 accumulation in 22Rv1[1]. RK-33-loaded NPs demonstrate cytotoxicity to MCF-7 cells in a dose-dependent manner, while equivalent doses of empty NPs have no killing effect. The IC50 value of 5% RK-33 loaded NPs is 49 μg/mL, and the IC50 value of 10% RK-33 loaded NPs is 25 μg/mL[2].
There is more cell death (pyknotic or condensed nuclei) admixed with fibrin and interstitial edema in the tumors from mice from the combination RK-33 and radiation group compared to the control or single treatment groups. The treatment combination of RK-33 and radiation has an advantage in reducing tumor proliferation[1]. In the mice treated with RK-33-PLGA, RK-33 can be detected in the plasma (34 μg/mL) and liver (28 μg/g), but not lungs[2].

Reference

[1]. Xie M,et al. RK-33 radiosensitizes prostate cancer cells by blocking the RNA helicase DDX3. Cancer Res. 2016 Sep 12.
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[2]. Bol GM, e tal. PLGA nanoparticle formulation of RK-33: an RNA helicase inhibitor against DDX3. Cancer Chemother Pharmacol. 2015 Oct;76(4):821-7.
 [Content Brief]