Tian Xiaoxia, Lu Junping, Nanding Kathleen, Zhang Linzhe, Liu Yanrong, Mailisu Mailisu, Morigen Morigen, Fan Lifei
State Key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, School of Life Sciences, Inner Mongolia University, Hohhot, China.
Front Oncol. 2022 Oct 13;12:828160. doi: 10.3389/fonc.2022.828160. eCollection 2022.
Breast cancer is the second cause of cancer death in women, and tumor metastasis is the primary cause of mortality. Due to the involvement of many regulatory molecules and signaling pathways, the occurrence and development of metastases needs to be further studied. MicroRNAs (miRNAs) are ubiquitously expressed small non-coding RNAs that have been shown to play an important role in the diagnosis and treatment of many diseases, as well as representing an attractive candidate for metastasis control. In this study, we investigated the mechanism of potassium piperonate (GBK) in impairing breast cancer cell invasion and metastasis by targeting miR-31.
Breast cancer cells, either treated with GBK or left untreated, were assessed for migration and invasion capacities using wound healing and transwell assays. GBK-targeted miRNAs were identified and verified using RT-qPCR. Western blotting was used to validate the changes in expression levels of miR-31-targeted genes. Methylation specific PCR was performed to detect the effect of GBK on the methylation levels of the lncRNA host gene. The synergistic effect of GBK and the chemotherapy drug cisplatin (DDP) on breast cancer cells was verified using cell proliferation, colony formation, and RT-qPCR assays , and the tumor xenograft model
We found that miR-31 was the main target of GBK. GBK treatment affected the epigenetic modification at CpG sites by downregulating DNA methyltransferases. Thus, the CpG-associated methylation levels of lncRNA decreased significantly, and in turn upregulated both miR-31 and its host gene in breast cancer cells. We also observed the significant inhibition of miR-31-targeted genes following GBK treatment, including , , and , with functions closely related to cancer cell invasion, migration, and proliferation. Furthermore, we revealed that the combination of GBK and DDP had a synergistic effect on inhibiting the proliferation of breast cancer cells and , especially in triple negative breast cancer (TNBC).
This study investigated the target of GBK in the inhibition of breast cancer migration and invasion, and the underlying mechanisms involved, providing theoretical support for the development of GBK as an auxiliary drug for clinical treatment.
乳腺癌是女性癌症死亡的第二大原因，肿瘤转移是主要的致死原因。由于涉及许多调控分子和信号通路，转移的发生和发展需要进一步研究。微小RNA（miRNA）是广泛表达的小非编码RNA，已被证明在许多疾病的诊断和治疗中发挥重要作用，也是转移控制的一个有吸引力的候选因素。在本研究中，我们研究了胡椒酸钾（GBK）通过靶向miR-31抑制乳腺癌细胞侵袭和转移的机制。
使用伤口愈合和Transwell实验评估经GBK处理或未处理的乳腺癌细胞的迁移和侵袭能力。使用RT-qPCR鉴定和验证GBK靶向的miRNA。蛋白质印迹法用于验证miR-31靶向基因表达水平的变化。进行甲基化特异性PCR以检测GBK对lncRNA宿主基因甲基化水平的影响。使用细胞增殖、集落形成和RT-qPCR实验以及肿瘤异种移植模型验证GBK与化疗药物顺铂（DDP）对乳腺癌细胞的协同作用。
我们发现miR-31是GBK的主要靶点。GBK处理通过下调DNA甲基转移酶影响CpG位点的表观遗传修饰。因此，lncRNA的CpG相关甲基化水平显著降低，进而上调乳腺癌细胞中miR-31及其宿主基因。我们还观察到GBK处理后miR-31靶向基因受到显著抑制，包括 、 和 ，其功能与癌细胞侵袭、迁移和增殖密切相关。此外，我们发现GBK和DDP联合使用对抑制乳腺癌细胞 和 的增殖具有协同作用，尤其是在三阴性乳腺癌（TNBC）中。
本研究探讨了GBK抑制乳腺癌迁移和侵袭的靶点及相关潜在机制，为GBK作为临床治疗辅助药物的开发提供了理论支持。
