Li Lihua, Zhang Xiaolian, Yi Zengxing, Liang Xiaofang, Yin Weihua, Li Shaoyuan
Department of Oncology, People's Hospital of Yichun, Jiangxi Province, China.
J BUON. 2018 May-Jun;23(3):579-586.
MicroRNAs are expressed abnormally in colorectal cancer (CRC) and could participate in its development. In this study we aimed to explore the molecular mechanisms of miR-503 in the genesis of CRC.
The relative expression of miR-503 and programmed cell death 4 (PDCD4) tumor suppressor in CRC tissues and cell lines were detected by qRT-PCR and Western blot. Cell migration and cell invasion were assessed by transwell assay. Moreover, the confirmation of the direct target of miR-503 in CRC was performed by luciferase reporter assay.
The expression of miR-503 was increased remarkably in CRC, while PDCD4 decreased. Moreover, PDCD4 was verified as a specific target of miR-503 in CRC and it could reverse the effect of miR-503 on CRC cells. Furthermore, the abnormal expression of miR-503 played an important role in regulating of the development of CRC cells. In addition, PDCD4 protein expression and miR-503 mRNA expression were negatively correlated in CRC tissues.
The inhibitory effect of miR-503 in CRC was realized by the upregulation of PDCD4, suggesting that miR-503/PDCD4 axis might play a critical role in CRC and could possibly be a therapeutic target.
微小RNA在结直肠癌（CRC）中异常表达，并可能参与其发展。在本研究中，我们旨在探讨miR - 503在CRC发生中的分子机制。
采用qRT - PCR和蛋白质免疫印迹法检测CRC组织和细胞系中miR - 503和程序性细胞死亡4（PDCD4）肿瘤抑制因子的相对表达。通过Transwell实验评估细胞迁移和侵袭能力。此外，通过荧光素酶报告基因实验验证miR - 503在CRC中的直接靶点。
miR - 503在CRC中表达显著增加，而PDCD4表达降低。此外，PDCD4被证实为CRC中miR - 503的特异性靶点，并且它可以逆转miR - 503对CRC细胞的影响。此外，miR - 503的异常表达在调节CRC细胞发展中起重要作用。另外，在CRC组织中，PDCD4蛋白表达与miR - 503 mRNA表达呈负相关。
miR - 503对CRC的抑制作用是通过上调PDCD4实现的，提示miR - 503/PDCD4轴可能在CRC中起关键作用，并且可能成为一个治疗靶点。
