Synthesis and biological evaluation of tetrahydropyridinepyrazoles (‘PFPs’) as inhibitors of STAT3 phosphorylation
作者:Revanna C. N、Basappa、Srinivasa V、Feng Li、Kodappully Sivaraman Siveen、Xiaoyun Dai、Shivananju Nanjunda Swamy、Bhadregowda D. G、Gautam Sethi、Mantelingu K、Andreas Bender、Rangappa KS
DOI:10.1039/c3md00119a
日期:——
The transcription factor STAT3 is constitutively overexpressed in many human tumors and hence represents a putative target for anticancer drug design. In this work, we describe the synthesis and biological evaluation of a novel chemotype, pyridine-fused pyrazoles (âPFPsâ) as inhibitors of STAT3 phosphorylation. The effect of the compounds synthesized was evaluated in cell proliferation assays of MCF-7 and HepG2 cancer cell lines and two of the compounds tested (12g and 12k) were found to show significant activity. Both compounds were also found to inhibit the proliferation of Hep3B, HUH-7 and PLC/PRF5 HCC cells in a dose- and time-dependent manner. Furthermore, we established in a DNA binding assay that one of the compounds (12g) was able to significantly inhibit the DNA binding ability of STAT3. Cytotoxicity of 12g against PC3 cells, which do not constitutively phosphorylate STAT3, was found to be minimal, hence lending further support for our mode-of-action hypothesis of this compound. We established for this structure a complete inhibition of CXCL12-induced cell invasion and associated wound healing in HCCLM3 cells, corroborating the proposed modulation of the STAT3 axis by 12g. Finally, molecular modeling was employed to evaluate the hypothesis of PFPs to bind to the SH2 domain of STAT3. Given the efficacy of PFPs in the biological systems studied here we propose their further evaluation in the context of STAT3-mediated cancer therapy.
转录因子STAT3在许多人類肿瘤中持续过表达,因此成为抗癌药物设计的一个潜在靶点。在本工作中,我们描述了合成一种新型化学类型——吡啶并吡唑(简称“PFPs”)作为STAT3磷酸化抑制剂,并对它们进行了生物学评估。通过在MCF-7和HepG2癌细胞系的细胞增殖实验中评估合成的化合物,发现其中两种化合物(12g和12k)显示出显著活性。这两种化合物还发现能以剂量和时间依赖的方式抑制Hep3B、HUH-7和PLC/PRF5肝癌细胞的增殖。此外,我们在DNA结合实验中证实,其中一种化合物(12g)能够显著抑制STAT3的DNA结合能力。对不持续磷酸化STAT3的PC3细胞,12g的细胞毒性极小,这进一步支持了我们对这种化合物作用机制的假设。我们在HCCLM3细胞中确立了对CXCL12诱导的细胞侵袭和相关伤口愈合的完全抑制,印证了12g对STAT3轴的调节作用。最后,分子建模用于评估PFPs结合到STAT3的SH2结构域的假设。鉴于PFPs在我们的生物学研究系统中的效力,我们建议在STAT3介导的癌症治疗背景下进一步评估它们。