A novel protein FNDC3B-267aa encoded by circ0003692 inhibits gastric cancer metastasis via promoting proteasomal degradation of c-Myc

作者全名：Liu, Yu-Ying; Zhang, Yu-Ying; Ran, Ling-Yu; Huang, Bo; Ren, Jun-Wu; Ma, Qiang; Pan, Xiao-Juan; Yang, Fei-Fei; Liang, Ce; Wang, Xiao-Lin; Wang, Shi-Min; Ran, Ai; Ning, Hao; Jiang, Yan; Qin, Chang-Hong; Xiao, Bin

作者地址：[Liu, Yu-Ying; Zhang, Yu-Ying; Huang, Bo; Ren, Jun-Wu; Ma, Qiang; Pan, Xiao-Juan; Yang, Fei-Fei; Liang, Ce; Wang, Xiao-Lin; Wang, Shi-Min; Ran, Ai; Ning, Hao; Jiang, Yan; Qin, Chang-Hong; Xiao, Bin] Chongqing Med Univ, Coll Pharm, Chongqing 400016, Peoples R China; [Ran, Ling-Yu] Army Med Univ, Southwest Hosp, Dept Kidney, Chongqing 400038, Peoples R China

通信作者：Xiao, B (通讯作者)，Chongqing Med Univ, Coll Pharm, Chongqing 400016, Peoples R China.

来源：JOURNAL OF TRANSLATIONAL MEDICINE

ESI学科分类：CLINICAL MEDICINE

WOS号：WOS:001233444200003

JCR分区：Q1

影响因子：6.1

年份：2024

卷号：22

期号：1

开始页：　

结束页：　

文献类型：Article

关键词：circ0003692; FNDC3B-267aa; c-Myc; Proteasomal degradation; Gastric cancer

摘要：Background Gastric cancer (GC) ranks fifth in global cancer incidence and third in mortality rate among all cancer types. Circular RNAs (circRNAs) have been extensively demonstrated to regulate multiple malignant biological behaviors in GC. Emerging evidence suggests that several circRNAs derived from FNDC3B play pivotal roles in cancer. However, the role of circFNDC3B in GC remains elusive.Methods We initially screened circFNDC3B with translation potential via bioinformatics algorithm prediction. Subsequently, Sanger sequencing, qRT-PCR, RNase R, RNA-FISH and nuclear-cytoplasmic fractionation assays were explored to assess the identification and localization of circ0003692, a circRNA derived from FNDC3B. qRT-PCR and ISH were performed to quantify expression of circ0003692 in human GC tissues and adjacent normal tissues. The protein-encoding ability of circ0003692 was investigated through dual-luciferase reporter assay and LC/MS. The biological behavior of circ0003692 in GC was confirmed via in vivo and in vitro experiments. Additionally, Co-IP and rescue experiments were performed to elucidate the interaction between the encoded protein and c-Myc.Results We found that circ0003692 was significantly downregulated in GC tissues. Circ0003692 had the potential to encode a novel protein FNDC3B-267aa, which was downregulated in GC cells. We verified that FNDC3B-267aa, rather than circ0003692, inhibited GC migration in vitro and in vivo. Mechanistically, FNDC3B-267aa directly interacted with c-Myc and promoted proteasomal degradation of c-Myc, resulting in the downregulation of c-Myc-Snail/Slug axis.Conclusions Our study revealed that the novel protein FNDC3B-267aa encoded by circ0003692 suppressed GC metastasis through binding to c-Myc and enhancing proteasome-mediated degradation of c-Myc. The study offers the potential applications of circ0003692 or FNDC3B-267aa as therapeutic targets for GC.Graphical abstract The mechanism of circ0003692 in suppressing metastasis of GC. FNDC3B-267aa encoded by circ0003692 interacted with c-Myc and promoted the proteasomal degradation of c-Myc, thereby down-regulated c-Myc-Snail/Slug axis and EMT pathway. Circ0003692 is decreased in GC and associated with T, N, M grade.Circ0003692 encodes a novel protein FNDC3B-267aa.Circ0003692 inhibits GC migration by translating FNDC3B-267aa.FNDC3B-267aa interacts with c-Myc and promotes its proteasomal degradation.

基金机构：National Natural Science Foundation of China

基金资助正文：We express our gratitude to Department of General Surgery, Southwest Hospital, Army Medical University for providing GC tissue samples.