AbstractCancer stem cells (CSCs) residing in colorectal cancer tissues have tumorigenic capacity and contribute to chemotherapeutic resistance and disease relapse. It is well known that the survival of colorectal CSCs after 5-fluorouracil (5-FU)-based therapy leads to cancer recurrence. Thus CSCs represent a promising drug target. Here, we designed and synthesized novel hybrid molecules linking 5-FU with the plant-derived compound thymoquinone (TQ) and tested the potential of individual compounds and their combination to eliminate colorectal CSCs. Both, Combi and SARB hybrid showed augmented cytotoxicity against colorectal cancer cells, but were non-toxic to organoids prepared from healthy murine small intestine. NanoString analysis revealed a unique signature of deregulated gene expression in response to the combination of TQ and 5-FU (Combi) and SARB treatment. Importantly, two principle stem cell regulatory pathways WNT/ß-Catenin and PI3K/AKT were found to be downregulated after Combi and hybrid treatment. Furthermore, both treatments strikingly eliminated CD133+ CSC population, accompanying the depleted self-renewal capacity by eradicating long-term propagated 3D tumor cell spheres at sub-toxic doses. In vivo xenografts on chicken eggs of SARB-treated HCT116 cells showed a prominent nuclear ß-Catenin and E-cadherin staining. This was in line with the reduced transcriptional activity of ß-Catenin and diminished cell adhesion under SARB exposure. In contrast to 5-FU, both, Combi and SARB treatment effectively reduced the angiogenic capacity of the remaining resistant tumor cells. Taken together, combination or hybridization of single compounds target simultaneously a broader spectrum of oncogenic pathways leading to an effective eradication of colorectal cancer cells.
摘要:结直肠癌组织中存在的癌干细胞(CSCs)具有肿瘤形成能力,并导致化疗抗药性和疾病复发。众所周知,结直肠CSCs在5-
氟尿
嘧啶(5-FU)基础治疗后的存活导致癌症复发。因此,CSCs代表了一个有前途的药物靶点。在这里,我们设计并合成了将5-FU与植物衍生化合物
百里香醌(TQ)连接的新型混合分子,并测试了单个化合物及其组合消除结直肠CSCs的潜力。Combi和
SARB混合物均显示出对结直肠癌细胞的增强细胞毒性,但对从健康小鼠小肠制备的器官样体无毒。NanoString分析显示,对TQ和5-FU(Combi)以及
SARB处理的组合具有独特的
基因表达失调特征。重要的是,两个主要的干细胞调控途径WNT/ß-Catenin和
PI3K/AKT在Combi和混合物处理后被发现下调。此外,这两种治疗显著消除了CD133+ CSC人口,通过根除长期传播的3D肿瘤细胞球在次毒性剂量下伴随着降低的自我更新能力。在
SARB处理的HCT116细胞的鸡蛋体内异种移植物上显示出明显的核β-连环蛋白和E-
钙粘蛋白染色。这与
SARB暴露下的β-连环蛋白的转录活性降低和细胞粘附减弱一致。与5-FU相比,Combi和
SARB治疗有效降低了剩余抗药性肿瘤细胞的血管生成能力。总的来说,单一化合物的组合或混合化同时靶向更广泛的致癌途径,从而有效根除结直肠癌细胞。