Tülüce Yasin, Köstekci Sedat, Karakuş Fuat, Keleş Ahmet Yasin, Tunçyürekli Merve
Department of Medical Biology, Faculty of Medicine, Van Yüzüncü Yıl University, Van, 65080, Türkiye.
Department of Molecular Biology and Genetics, Institute of Natural and Applied Sciences, Van Yüzüncü Yıl University, Van, 65080, Türkiye.
Mol Biol Rep. 2025 Mar 19;52(1):326. doi: 10.1007/s11033-025-10435-0.
In the present study, we investigated the immunotherapeutic and anticancer activities of microRNA-4477a (miR-4477a) as a PD-L1 inhibitor in breast cancer cells (MCF-7).
To this end, a series of analytical procedures were conducted, including bioinformatic analysis, RT-PCR analysis, PD-L1 ELISA, in vitro co-culture analysis, cytotoxicity assays, cell migration assays, and colony formation assays, with the objective of determining the anticancer activity of the compound in question.
The results demonstrated that miR-4477a can bind to three distinct regions of PD-L1 mRNA with high scores (94%, 88% and 80%), effectively targeting and suppressing the crucial regulatory pathways of cancer cells. In vitro studies demonstrated that a 25 nM dose of miR-4477a caused relatively high cytotoxicity in the MCF-7 cell line, suppressed PD-L1 gene expression, and decreased sPD-L1 protein levels, strongly inhibited cell migration, and significantly reduced colony formation. The in vitro co-culture analysis revealed that cancer cells were unable to evade the surveillance and cytotoxic activity of T cells (CD8) due to the blockade of PD-L1 expression by miR-4477a.
In conclusion, miRNA-4477a has the capacity to regulate immune responses in breast cancer cells and may therefore be a promising candidate for use in cancer immunotherapy as a therapeutic agent.
在本研究中，我们调查了微小RNA-4477a（miR-4477a）作为程序性死亡受体配体1（PD-L1）抑制剂在乳腺癌细胞（MCF-7）中的免疫治疗和抗癌活性。
为此，进行了一系列分析程序，包括生物信息学分析、逆转录-聚合酶链反应（RT-PCR）分析、PD-L1酶联免疫吸附测定（ELISA）、体外共培养分析、细胞毒性测定、细胞迁移测定和集落形成测定，目的是确定所研究化合物的抗癌活性。
结果表明，miR-4477a能以高分（94%、88%和80%）与PD-L1 mRNA的三个不同区域结合，有效靶向并抑制癌细胞的关键调控途径。体外研究表明，25 nM剂量的miR-4477a在MCF-7细胞系中引起相对较高的细胞毒性，抑制PD-L1基因表达，降低可溶性PD-L1蛋白水平，强烈抑制细胞迁移，并显著减少集落形成。体外共培养分析显示，由于miR-4477a阻断了PD-L1的表达，癌细胞无法逃避T细胞（CD8）的监视和细胞毒性活性。
总之，微小RNA-4477a有能力调节乳腺癌细胞中的免疫反应，因此可能是一种有前途的癌症免疫治疗候选药物。
