HMN-176 is a stilbene derivative which inhibits mitosis, interfering with polo-like kinase-1 (plk1), without significant effect on tubulin polymerization.
HMN-176 (2.5 uM) greatly increases the duration of mitosis in hTERT-RPE1 and CFPAC-1 Cell lines. The effect of HMN-176 on spindle morphology does not appear to be related to effects on microtubule polymerization. HMN-176 (2.5, 0.25, and 0.025 uM) inhibits aster formation in a concentration dependent manner[1]. HMN-176 (0.1, 1.0, or 10.0 ug/mL) demonstrates inhibitory effects in multiple tumors, with notable activity seen in breast, nonsmall-cell lung, and ovarian cancer specimens. HMN-176 demonstrates activity towards 63% of the breast (5/8), 67% of the non-small cell lung (4/6), and 57% of the ovarian (4/7) tumor specimens treated with 10.0 ug/mL[2]. HMN-176 shows potent cytotoxicity, with a mean IC50 value of 118 nM. HMN-176 displays similar cytotoxicity against tumors with various characteristics from different organs[3]. Treatment with 3 uM HMN-176 suppresses the expression of MDR1 mRNA by 56%. HMN-176 has no significant effect on the residual promoter activity[4].
HMN-176 prevents spindle assembly and meiosis in Spisula oocytes by inhibiting centrosome-dependent MT nucleation, i.e., aster formation. Oocytes treated with 0.25 uM HMN-176 undergoes GVBD, but asters or spindles fails to form, even after prolonged periods[1]. After p.o. of HMN-214 to male rats, the prodrug is not detected in the plasma, while plasma levels of HMN-176 peaks at 2 h and gradually decreases thereafter[3].
References:
[1]. DiMaio MA, et al. The small organic compound HMN-176 delays satisfaction of the spindle assembly checkpoint by inhibiting centrosome-dependent microtubule nucleation. Mol Cancer Ther. 2009 Mar;8(3):592-601.
[2]. Medina-Gundrum L, et al. Investigation of HMN-176 anticancer activity in human tumor specimens in vitro and the effects of HMN-176 on differential gene expression. Invest New Drugs. 2005 Jan;23(1):3-9.
[3]. Takagi M, et al. In vivo antitumor activity of a novel sulfonamide, HMN-214, against human tumor xenografts in mice and the spectrum of cytotoxicity of its active metabolite, HMN-176. Invest New Drugs. 2003 Nov;21(4):387-99.
[4]. Tanaka H, et al. HMN-176, an active metabolite of the synthetic antitumor agent HMN-214, restores chemosensitivity to multidrug-resistant cells by targeting the transcription factor NF-Y. Cancer Res. 2003 Oct 15;63(20):6942-7.
[5]. Garland LL, et al. A phase I pharmacokinetic study of HMN-214, a novel oral stilbene derivative with polo-like kinase-1-interacting properties, in patients with advanced solid tumors. Clin Cancer Res. 2006 Sep 1;12(17):5182-9.