Emam Ahmed A, Abo-Elkhair Salwa M, Sobh Mohamed, El-Sokkary Ahmed M A
Medical Experimental Research Center (MERC), Faculty of Medicine, Mansoura University, Egypt.
Medical Biochemistry and Molecular Biology Department, Faculty of Medicine, Mansoura University, Egypt.
Heliyon. 2021 Apr 8;7(4):e06698. doi: 10.1016/j.heliyon.2021.e06698. eCollection 2021 Apr.
Micro-RNAs (MiRNAs) are a class of small non-coding RNAs that regulate cellular gene expression. MiR-155 overexpression has been implicated in many types of cancer. Besides, miR-155 appears to help tumor invasion and migration and works as a moderator of epithelial-to-mesenchymal transition (EMT). Exopolysaccharides (EPSs) are a large group of natural heterogeneous polymers of sugars with a biologically antitumor effect. Herein, we test a hypothesis that EPS might promote its anti-tumorigenic effect regulating miR-155 expression and its target pathways. Expression of miR-155 and a panel of targeted genes were investigated by real-time PCR. In our study, we have succeeded in the extraction, purification of exopolysaccharide with great cytotoxicity to different cancer cell lines, HepG II, Caco-2, and MCF-7. We reported that EPSs have a suppression effect on the oncogenic miR-155. In conclusion, this work clarifies a new possible mechanism for the anti-tumorigenic effect of EPSs in cancer cells and provides insights into the biological pathways through which EPSs act. Moreover, it paves the way for new prospective cancer therapeutics as anti-miRNA.
微小RNA（miRNA）是一类可调节细胞基因表达的小型非编码RNA。miR-155的过表达与多种癌症有关。此外，miR-155似乎有助于肿瘤侵袭和迁移，并在上皮-间质转化（EMT）过程中起调节作用。胞外多糖（EPS）是一类具有生物抗肿瘤作用的天然异质糖聚合物。在此，我们验证了一个假设，即EPS可能通过调节miR-155的表达及其靶途径来增强其抗肿瘤作用。通过实时PCR研究miR-155和一组靶向基因的表达。在我们的研究中，我们成功提取并纯化了对不同癌细胞系HepG II、Caco-2和MCF-7具有高度细胞毒性的胞外多糖。我们报道EPS对致癌性miR-155具有抑制作用。总之，这项工作阐明了EPS在癌细胞中抗肿瘤作用的一种新的可能机制，并深入了解了EPS发挥作用的生物学途径。此外，它为作为抗miRNA的新型前瞻性癌症治疗方法铺平了道路。
