Zhang Jin, Song Ni, Duan Zhongqi
Urinary Surgery Department, The Second Hospital of Yulin, Yulin, China.
Geriatric Department, Xianyang Central Hospital, Xianyang, China.
J Cell Biochem. 2019 May;120(5):7297-7308. doi: 10.1002/jcb.28004. Epub 2018 Nov 1.
In this study, we evaluated the effect of rs6265 polymorphism on the expression of brain-derived neurotrophic factor (BDNF) and relevant downstream targets, as well as the involvement of this polymorphism in bladder cancer.
A computational analysis and luciferase assays were used to explore the interaction among BDNF, miR-205, and cyclin J (CCNJ). Real-time polymerase chain reaction (RT-PCR) and Western blot analysis were carried out to determine the effect of rs6265 polymorphism on the expression of BDNF and relevant downstream genes.
BDNF directly inhibited miR-205 expression but enhanced the expression of CCNJ, which was identified as a virtual target gene of miR-205. Furthermore, the inhibitory effect of BDNF carrying the Val genotype, defined as BDNF (Val), on miR-205 expression was much stronger than that of BDNF (Met), while the inductive effect of BDNF (Val) on CCNJ expression was much weaker than that of BDNF (Met). miR-205 and CCNJ small interfering RNA (siRNA) were found to reduce cell proliferation and arrest the cells in G0/G1 phase. In addition, miR-205 expression in patients carrying BDNF genotyped as Met/Met (defined as Met/Met group) was much higher than patients carrying BDNF genotyped as Val/Val and Val/Met (defined as Val/Val group and Val/Met group). As an inhibitor of CCNJ expression, the inhibitory effect of miR-205 was much higher in the Met/Met group than that in the Val/Val and Val/Met groups.
In summary, we suggested that the rs6265 polymorphism in BDNF upregulates the expression of CCNJ in bladder cancer via the inhibition of miR-205 expression, which leads to the promoted proliferation of bladder cancer cells.
在本研究中，我们评估了rs6265多态性对脑源性神经营养因子（BDNF）及其相关下游靶点表达的影响，以及该多态性与膀胱癌的关系。
采用计算分析和荧光素酶测定法探究BDNF、miR-205和细胞周期蛋白J（CCNJ）之间的相互作用。通过实时聚合酶链反应（RT-PCR）和蛋白质免疫印迹分析来确定rs6265多态性对BDNF及相关下游基因表达的影响。
BDNF直接抑制miR-205的表达，但增强CCNJ的表达，CCNJ被确定为miR-205的一个潜在靶基因。此外，携带Val基因型的BDNF（定义为BDNF（Val））对miR-205表达的抑制作用比BDNF（Met）更强，而BDNF（Val）对CCNJ表达的诱导作用比BDNF（Met）更弱。发现miR-205和CCNJ小干扰RNA（siRNA）可降低细胞增殖并使细胞停滞于G0/G1期。此外，携带BDNF基因型为Met/Met（定义为Met/Met组）的患者中miR-205的表达远高于携带BDNF基因型为Val/Val和Val/Met（定义为Val/Val组和Val/Met组）的患者。作为CCNJ表达的抑制剂，miR-205在Met/Met组中的抑制作用高于Val/Val组和Val/Met组。
总之，我们认为BDNF中的rs6265多态性通过抑制miR-205的表达上调膀胱癌中CCNJ的表达，从而导致膀胱癌细胞增殖增加。
