Department of Pharmaceutical Technology and Chemistry, School of Pharmacy and Nutrition, University of Navarra, Irunlarrea 1, E-31008 Pamplona, Spain.
Instituto de Investigación Sanitaria de Navarra (IdiSNA), Irunlarrea 3, E-31008 Pamplona, Spain.
Int J Mol Sci. 2019 Jan 26;20(3):521. doi: 10.3390/ijms20030521.
The prognosis for patients with metastatic melanoma remains very poor. Constitutive signal transducer and activator of transcription 3 (STAT3) activation has been correlated to metastasis, poor patient survival, larger tumor size, and acquired resistance against vemurafenib (PLX-4032), suggesting its potential as a molecular target. We recently designed a series of isoseleno- and isothio-urea derivatives of several biologically active heterocyclic scaffolds. The cytotoxic effects of lead isoseleno- and isothio-urea derivatives (compounds 1 and 3) were studied in a panel of five melanoma cell lines, including B-RAF-mutant and wild-type (WT) cells. Compound 1 (IC range 0.8⁻3.8 µM) showed lower IC values than compound 3 (IC range 8.1⁻38.7 µM) and the mutant B-RAF specific inhibitor PLX-4032 (IC ranging from 0.4 to >50 µM), especially at a short treatment time (24 h). These effects were long-lasting, since melanoma cells did not recover their proliferative potential after 14 days of treatment. In addition, we confirmed that compound 1 induced cell death by apoptosis using Live-and-Dead, Annexin V, and Caspase3/7 apoptosis assays. Furthermore, compound 1 reduced the protein levels of STAT3 and its phosphorylation, as well as decreased the expression of STAT3-regulated genes involved in metastasis and survival, such as survivin and c-myc. Compound 1 also upregulated the cell cycle inhibitor p21. Docking studies further revealed the favorable binding of compound 1 with the SH2 domain of STAT3, suggesting it acts through STAT3 inhibition. Taken together, our results suggest that compound 1 induces apoptosis by means of the inhibition of the STAT3 pathway, non-specifically targeting both B-RAF-mutant and WT melanoma cells, with much higher cytotoxicity than the current therapeutic drug PLX-4032.
转移性黑色素瘤患者的预后仍然非常差。组成性信号转导和转录激活因子 3（STAT3）的激活与转移、患者生存不良、肿瘤体积较大以及对 vemurafenib（PLX-4032）产生获得性耐药有关，提示其作为分子靶标的潜力。我们最近设计了一系列具有生物活性的杂环骨架的异硒代和异硫代脲衍生物。在包括 B-RAF 突变和野生型（WT）细胞在内的五株黑色素瘤细胞系中研究了先导异硒代和异硫代脲衍生物（化合物 1 和 3）的细胞毒性作用。化合物 1（IC 范围 0.8-3.8 µM）的 IC 值低于化合物 3（IC 范围 8.1-38.7 µM）和 B-RAF 特异性抑制剂 PLX-4032（IC 范围从 0.4 到> 50 µM），尤其是在较短的治疗时间（24 小时）。这些作用是持久的，因为黑色素瘤细胞在治疗 14 天后并没有恢复其增殖能力。此外，我们通过 Live-and-Dead、Annexin V 和 Caspase3/7 凋亡测定证实，化合物 1 通过诱导细胞凋亡导致细胞死亡。此外，化合物 1 降低了 STAT3 及其磷酸化的蛋白水平，并降低了参与转移和存活的 STAT3 调节基因的表达，如 survivin 和 c-myc。化合物 1 还上调了细胞周期抑制剂 p21。对接研究进一步表明，化合物 1 与 STAT3 的 SH2 结构域具有良好的结合，表明其通过抑制 STAT3 起作用。综上所述，我们的结果表明，化合物 1 通过抑制 STAT3 通路诱导细胞凋亡，非特异性地靶向 B-RAF 突变和 WT 黑色素瘤细胞，其细胞毒性比目前的治疗药物 PLX-4032 高得多。
