Department of Ophthalmology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China.
J Cell Biochem. 2020 Jul;121(7):3516-3525. doi: 10.1002/jcb.29631. Epub 2020 Feb 17.
It is growingly recognized that messenger RNAs (mRNAs) are important regulators of various cancers. However, there are few reporters about the function of E2F3 in retinoblastoma (RB), which needs more exploration. In addition, the circRNA circ-0075804 was derived from the E2F3 host gene. The purpose of the study is to figure out the role and molecular regulation mechanism of E2F3 and circ-0075804 in RB. The role of E2F3 in RB was determined through E2F3 silencing and loss of expression was evaluated by real-time quantitative polymerase chain reaction (RT-qPCR), Western blot, CCK-8, colony formation, and 5-ethynyl-2'-deoxyuridine assays. The interactions between E2F3 and circ-0075804 were validated through loss and gain function of circ-0075804. Besides, the role of circ-0075804 in RB was determined by several functional assays. And the binding ability between heterogeneous nuclear ribonucleoprotein K and circ-0075804 was verified by RNA pull-down, Western blot, and RT-qPCR assays. The expression of E2F3 was upregulated in RB cell lines. Furthermore, knockdown of E2F3 inhibited cell proliferation and induced cell apoptosis in RB. And circ-0075804 positively regulated the expression of E2F3. Moreover, circ-0075804 facilitated cell proliferation and suppressed cell apoptosis. Besides, HNRNPK could bind with circ-0075804 in RB. Finally, knockdown of E2F3 partly rescued the promoting role of circ-0075804 overexpression in RB. Overall, circ-0075804 promotes the proliferation of RB via combining HNRNPK to improve the stability of E2F3, which brings new light for treating RB.
越来越多的人认识到信使 RNA（mRNA）是各种癌症的重要调节剂。然而，关于 E2F3 在视网膜母细胞瘤（RB）中的作用的报道很少，这需要更多的探索。此外，circRNA circ-0075804 来源于 E2F3 宿主基因。本研究的目的是探讨 E2F3 和 circ-0075804 在 RB 中的作用和分子调节机制。通过 E2F3 沉默来确定 E2F3 在 RB 中的作用，并通过实时定量聚合酶链反应（RT-qPCR）、Western blot、CCK-8、集落形成和 5-乙炔基-2'-脱氧尿苷测定评估 E2F3 的缺失和表达。通过 circ-0075804 的缺失和获得功能来验证 E2F3 和 circ-0075804 之间的相互作用。此外，通过几种功能测定来确定 circ-0075804 在 RB 中的作用。并通过 RNA 下拉、Western blot 和 RT-qPCR 测定验证异质核核糖核蛋白 K 与 circ-0075804 之间的结合能力。E2F3 在 RB 细胞系中的表达上调。此外，E2F3 的敲低抑制了 RB 中的细胞增殖并诱导了细胞凋亡。并且 circ-0075804 正向调节 E2F3 的表达。此外，circ-0075804 促进细胞增殖并抑制细胞凋亡。此外，HNRNPK 可以与 RB 中的 circ-0075804 结合。最后，circ-0075804 过表达促进 RB 作用的部分挽救了 E2F3 敲低的作用。总的来说，circ-0075804 通过与 HNRNPK 结合来提高 E2F3 的稳定性，从而促进 RB 的增殖，为治疗 RB 带来了新的思路。
