A novel protein encoded by circFNDC3B inhibits tumor progression and EMT through regulating Snail in colon cancer
A novel protein encoded by circFNDC3B inhibits tumor progression and EMT through regulating Snail in colon cancer
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circFNDC3B编码的新型蛋白质通过调节结肠癌中的Snail抑制肿瘤进展和EMT
DOI：
10.1186/s12943-020-01179-5
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发表时间：
2020-04-02
期刊：
影响因子：
37.3
通讯作者：
Zhang, Lei
中科院分区：
文献类型：
--
作者：
Pan, Zihao;Cai, Jianye;Zhang, Lei
结肠癌（Colon cancer，CC）是一种常见的恶性肿瘤。最近，发现circFNDC 3B在多种癌症中发挥生物学功能。方法采用桑格序列测定和RNase R酶切实验证实circFNDC 3B基因的存在，实时荧光定量PCR检测circRNA的表达。采用荧光原位杂交（FISH）技术对circFNDC 3B基因进行定位。采用LC-MS/MS鉴定circFNDC 3B编码的蛋白质。通过CCK 8测定、集落形成测定、transwell测定、伤口愈合测定和动物实验评估circFNDC 3B-218 aa对增殖、侵袭和迁移的作用。通过RNA测序和western blot鉴定circFNDC 3B-218 aa调控的基因。结果CircFNDC 3B主要定位于细胞质中，在CC细胞系和组织中表达减少。circFNDC 3B低表达患者的OS比高表达患者短（P= 0.0014）。此外，circFNDC 3B抑制CC细胞的增殖、侵袭和迁移。接下来，我们鉴定了circFNDC 3B可以编码一个新的蛋白circFNDC 3B-218 aa。此外，circFNDC 3B-218 aa而不是circFNDC 3B抑制CC的增殖、侵袭和迁移。此外，体内实验表明，上调的circFNDC 3B-218 aa对CC进展表现出抑制作用。通过RNA测序、western blot和糖代谢相关分析，发现circFNDC 3B-218 aa抑制了Snail的表达，并促进了FBP 1的抑瘤作用。结论circFNDC 3B-218 aa可能作为一种肿瘤抑制因子和潜在的生物标志物，为CC的治疗提供了潜在的靶点。
BackgroundColon cancer (CC) is a common malignant cancer. Recently, circFNDC3B was found to exert biological function in multiple cancers. However, it was unclear whether the potential protein encoded by circFNDC3B is involved in carcinogenesis of CC.MethodsWe used Sanger sequence and RNase R digestion assay to confirm the existence of circFNDC3B, and quantitative real-time PCR was used to evaluate the circRNA’s expression. Then fluorescence in situ hybridization (FISH) was performed to study location of circFNDC3B. The identification of protein encoded by circFNDC3B was performed using LC-MS/MS. The function of circFNDC3B-218aa on proliferation, invasion and migration were assessed by CCK8 assays, colony formation assays, transwell assays, wound-healing assays and animal experiments. RNA-sequencing and western blot were used to identify the gene regulated by circFNDC3B-218aa. Finally, glucose metabolism-related assays were performed to further investigate function of circFNDC3B-218aa.ResultsCircFNDC3B was localized mostly in the cytoplasm, and was decreased in CC cell lines and tissues. The patients with low circFNDC3B expression had a shorter OS (P= 0.0014) than patients with high expression. Moreover, circFNDC3B inhibited the proliferation, invasion and migration of CC cells. Next, we identified that circFNDC3B could encode a novel protein circFNDC3B-218aa. Furthermore, circFNDC3B-218aa, not circFNDC3B, inhibited the proliferation, invasion and migration of CC. Additionally, the in vivo experiments implied that up-regulated circFNDC3B-218aa exhibited an inhibitory effect on CC progression. By RNA-sequencing, western blot and glucose metabolism-related assays, we found that circFNDC3B-218aa inhibited the expression of Snail, and subsequently promoted the tumor-suppressive effect of FBP1 in CC.ConclusionsThe novel circFNDC3B-218aa may serve as a tumor suppressive factor and potential biomarker which may supply the potential therapeutic target for CC.