目的:胆管癌(CCA)是由肝内(iCCA)或肝外(eCCA)胆管引起的侵袭性恶性肿瘤,预后差,治疗选择有限。先前的证据强调了非规范NF-κB信号通路在不同肿瘤类型的起始和侵袭性中的重要贡献。淋巴毒素β(LTβ)刺激NF-κB诱导激酶(NIK),导致转录因子RelB的激活。然而,通过LTβ/NIK/RelB轴的非经典NF-κB信号通路在CCA癌变和进展中的功能贡献尚未确定。
方法:检测人CCA来源的细胞系和类器官,以确定活化或抑制后NF-κB途径组分的表达。使用实时阻抗测量和流式细胞术分析增殖和细胞死亡。免疫印迹,qRT-PCR,RNA测序和原位杂交用于分析基因和蛋白质表达。使用iCCA的四个体内模型来探测非常规NF-κB途径的激活和调节。
结果:暴露于LTα1/β2会激活LTβ/NIK/RelB轴并促进CCA中的增殖。用小分子抑制剂B022抑制NIK有效地抑制了患者来源的CCA类器官中的RelB表达以及CCA细胞系中由LTα1/β2刺激的RelB和p52的核共转位。在鼠类CCA中,RelB表达显著增加,并且LTβ是非经典NF-κB信号传导途径的主要配体。
结论:我们的研究证实,非经典NF-κB轴LTβ/NIK/RelB驱动了胆管癌的发生,并代表了一个候选治疗靶点。
OBJECTIVE: Cholangiocarcinoma (CCA) is an aggressive malignancy arising from the intrahepatic (iCCA) or extrahepatic (eCCA) bile ducts with poor prognosis and limited treatment options. Prior evidence highlighted a significant contribution of the non-canonical NF-κB signalling pathway in initiation and aggressiveness of different tumour types. Lymphotoxin-β (LTβ) stimulates the NF-κB-inducing kinase (
NIK), resulting in the activation of the transcription factor RelB. However, the functional contribution of the non-canonical NF-κB signalling pathway via the LTβ/
NIK/RelB axis in CCA carcinogenesis and progression has not been established.
METHODS: Human CCA-derived cell lines and organoids were examined to determine the expression of NF-κB pathway components upon activation or inhibition. Proliferation and cell death were analysed using real-time impedance measurement and flow cytometry. Immunoblot, qRT-PCR, RNA sequencing and in situ hybridization were employed to analyse gene and protein expression. Four in vivo models of iCCA were used to probe the activation and regulation of the non-canonical NF-κB pathway.
RESULTS: Exposure to LTα1/β2 activates the LTβ/
NIK/RelB axis and promotes proliferation in CCA. Inhibition of
NIK with the small molecule inhibitor B022 efficiently suppresses RelB expression in patient-derived CCA organoids and nuclear co-translocation of RelB and p52 stimulated by LTα1/β2 in CCA cell lines. In murine CCA, RelB expression is significantly increased and LTβ is the predominant ligand of the non-canonical NF-κB signalling pathway.
CONCLUSIONS: Our study confirms that the non-canonical NF-κB axis LTβ/
NIK/RelB drives cholangiocarcinogenesis and represents a candidate therapeutic target.