Department of Gastroenterology, The Affiliated Hospital of Inner Mongolia Medical University, Hohhot, Inner Mongolia, China.
Eur Rev Med Pharmacol Sci. 2019 Jul;23(14):6105-6118. doi: 10.26355/eurrev_201907_18424.
Previous reports have shown that long non-coding RNAs (lncRNAs) are involved in a series of biological processes and cancer in humans. Recently, lncRNA double homeobox A pseudogene 8 (DUXAP8) was frequently reported to be aberrantly expressed in multiple cancers and play a functional role. However, the exact expression, function, and mechanism of DUXAP8 in colorectal cancer (CRC) remain uncovered.
The expression levels of DUXAP8 were detected by Reverse Transcription-Polymerase Chain Reaction (RT-PCR). The clinical influence of DUXAP8 in HCC patients was statistically analyzed. Luciferase reporter and ChIP assays were carried out for the exploration of whether STAT3 was able to bind to the promoter of DUXAP8. Lost-of-function experiments were carried out for the determination of possible cellular function in CRC cells. The modulating associations between DUXAP8 and miR-577 and RAB14 were further studied in CRC cells.
In this study, we first provided evidence that DUXAP8 was overexpressed in CRC and increasing expression of DUXAP8 indicates advanced clinical progression and poor survival of CRC patients. Then, transcription factor STAT3 was demonstrated to upregulate DUXAP8 in CRC cells. Functional assays via in vitro assays revealed that DUXAP8 knockdown through shRNA in HCT116 and LOVO cells inhibited cell proliferation, migration and invasion, and promoted apoptosis. Furthermore, an inverse relationship between DUXAP8 and miR-577 was found. In addition, we confirmed that DUXAP8 served as competing endogenous RNA to modulate miR-577, which can modulate RAB14, a well-studied oncogene.
Our study revealed that the STAT3-induced up-regulation of DUXAP8 might provide a new perspective for CRC therapy.
先前的报告表明，长非编码 RNA（lncRNA）参与了一系列生物过程和人类癌症。最近，lncRNA 双同源盒 A 假基因 8（DUXAP8）频繁报道在多种癌症中异常表达，并发挥功能作用。然而，DUXAP8 在结直肠癌（CRC）中的确切表达、功能和机制仍未被揭示。
通过逆转录-聚合酶链反应（RT-PCR）检测 DUXAP8 的表达水平。对 HCC 患者 DUXAP8 的临床影响进行统计学分析。进行荧光素酶报告和 ChIP 测定，以探究 STAT3 是否能够与 DUXAP8 的启动子结合。进行失活功能实验，以确定 CRC 细胞中可能的细胞功能。进一步研究 CRC 细胞中 DUXAP8 与 miR-577 和 RAB14 的调节关联。
在本研究中，我们首先提供了证据表明 DUXAP8 在 CRC 中过表达，并且 DUXAP8 表达的增加表明 CRC 患者的临床进展更晚期和生存不良。然后，转录因子 STAT3 被证明在 CRC 细胞中上调 DUXAP8。通过 shRNA 在 HCT116 和 LOVO 细胞中进行的体外功能测定显示，DUXAP8 敲低抑制细胞增殖、迁移和侵袭，并促进细胞凋亡。此外，还发现了 DUXAP8 与 miR-577 之间的负相关关系。此外，我们证实 DUXAP8 作为竞争性内源性 RNA 来调节 miR-577，miR-577 可以调节 RAB14，RAB14 是一个研究充分的癌基因。
我们的研究表明，STAT3 诱导的 DUXAP8 上调可能为 CRC 治疗提供新的视角。
