Sustained expression of B-cell receptor (BCR) critically contributes to the development of diffuse large B-cell lymphoma (DLBCL). However, little is known on the mechanism regulating BCR expression. In the present study, we explored the biological significance of functional intergenic repeating RNA element (FIRRE) in DLBCL and its regulation on BCR. Functional impacts of FIRRE on cell viability, transformation, and apoptosis were examined by MTT, colony formation, and flow cytometry, respectively. The interaction between FIRRE and polypyrimidine tract binding protein 1 (PTBP1) was identified by RNA pull-down and verified using RNA immunoprecipitation (RIP) assays. The effects of FIRRE and PTBP1 on Smurf2 mRNA were examined by RIP, RNA pull-down, and mRNA stability assays. Smurf2-mediated BCR ubiquitination was investigated using co-immunoprecipitation, ubiquitination, and protein stability assays. In vivo, xenograft models were used to assess the impacts of targeting FIRRE on DLBCL growth. FIRRE was specifically up-regulated in and essentially maintained multiple malignant behaviors of BCR-dependent DLBCL cells. Through the interaction with PTBP1, FIRRE promoted the mRNA decay of Smurf2, a ubiquitin ligase for the degradation BCR protein. Targeting FIRRE was sufficient to regulat Smurf2 and BCR expressions and inhibit DLBCL malignancy both in vivo and in vitro. FIRRE-PTBP1 interaction, by simulating Smurf2 mRNA decay and stabilizing BCR, promotes the development of DLBCL. Consequently, targeting this signaling mechanism may provide therapeutic benefits for DLBCL.Keywords: B-cell receptor; DLBCL; FIRRE; PTBP1; Smurf2.

---

 

乐备实（上海优宁维生物科技股份有限公司旗下全资子公司），是国内专注于提供高质量蛋白检测以及组学分析服务的实验服务专家，自2018年成立以来，乐备实不断寻求突破，公司的服务技术平台已扩展到单细胞测序、空间多组学、流式检测、超敏电化学发光、Luminex多因子检测、抗体芯片、PCR Array、ELISA、Elispot、PLA蛋白互作、多色免疫组化、DSP空间多组学等30多个，建立起了一套涵盖基因、蛋白、细胞以及组织水平实验的完整检测体系。

 
我们可提供从样本运输、储存管理、样本制备、样本检测到检测数据分析的全流程服务。凭借严格的实验室管理流程、标准化实验室操作、原始数据储存体系以及实验项目管理系统，已经为超过3000家客户单位提供服务，年检测样本超过100万，受到了广大客户的信任与支持。