Department of Hematology, the Affiliated Hospital of Inner Mongolia Medical University, Hohhot, 010050, China.
Cancer Med. 2018 Jan;7(1):134-145. doi: 10.1002/cam4.1181. Epub 2017 Dec 7.
Although many efforts have contributed to improve our knowledge of molecular pathogenesis about multiple myeloma (MM), the role and significance of microRNAs and long noncoding RNAs in MM cells, along with the core mechanism remains virtually absent. The mRNA levels of miR-125b and MALAT1 in MM cell lines were detected by qRT-PCR. The influence of Lenti-Sh-miR-125b on cell viability and the Notch-1 pathway-related proteins were assessed by MTT method and western blot, respectively. We also investigated the regulation effect between MALAT1 and Notch1 pathway. Moreover, the connection between Notch1 signaling and MM cell growth was discussed in-depth. The reverse effect of pcDNA-Notch1 on the cell viability and Notch-1 pathway proteins induced by Si-MALAT1 was also studied. Furthermore, miR-125b overexpressing MM cell lines were injected subcutaneously into nude mice. MiR-125b and MALAT1 were inversely expressed in MM cell lines. Lenti-Sh-miR-125b inhibited the expression of MALAT1 and Notch-1 protein. Binding sites were confirmed between miR-125b and MALAT1, and silencing MALAT1 did not alter the expression of Notch-1. The apoptosis rate was increased and the survival rate was decreased obviously in GSI XII (targeted cleavage of Notch-1 receptor) group, along with the inhibited Notch1 and HES1 proteins. Moreover, the decreased cell viability and Notch-1 pathway proteins induced by Si-MALAT1 could be reversed by pcDNA-Notch1. Lenti-Sh-miR-125b promoted survival and decreased Notch1 and HES1 proteins levels, while this effect was reversed by si -MALAT1. MiR-125b regulated MALAT1 expression via Notch1 signaling pathway to regulate cell growth, thus participating in the occurrence and progression of MM, which functioned as a therapeutic target for tracking MM.
尽管人们做出了许多努力来提高我们对多发性骨髓瘤（MM）分子发病机制的认识，但微 RNA 和长非编码 RNA 在 MM 细胞中的作用和意义，以及核心机制实际上仍然未知。qRT-PCR 检测 MM 细胞系中 miR-125b 和 MALAT1 的 mRNA 水平。MTT 法和 Western blot 分别评估 Lenti-Sh-miR-125b 对细胞活力和 Notch-1 通路相关蛋白的影响。我们还研究了 MALAT1 与 Notch1 通路之间的调节作用。此外，还深入探讨了 Notch1 信号与 MM 细胞生长之间的关系。还研究了 pcDNA-Notch1 对 Si-MALAT1 诱导的细胞活力和 Notch-1 通路蛋白的反向作用。进一步，将 miR-125b 过表达 MM 细胞系皮下注射到裸鼠中。MM 细胞系中 miR-125b 和 MALAT1 的表达呈负相关。Lenti-Sh-miR-125b 抑制 MALAT1 和 Notch-1 蛋白的表达。miR-125b 和 MALAT1 之间存在结合位点，沉默 MALAT1 不会改变 Notch-1 的表达。GSI XII（靶向 Notch-1 受体的切割）组中细胞凋亡率增加，存活率明显降低，同时 Notch1 和 HES1 蛋白受到抑制。此外，Si-MALAT1 诱导的细胞活力降低和 Notch-1 通路蛋白表达降低可被 pcDNA-Notch1 逆转。Lenti-Sh-miR-125b 促进存活并降低 Notch1 和 HES1 蛋白水平，而 Si-MALAT1 可逆转这种作用。miR-125b 通过 Notch1 信号通路调节 MALAT1 的表达，从而调节细胞生长，参与 MM 的发生和进展，可作为追踪 MM 的治疗靶点。
