作为唯一用于骨巨细胞瘤（GCTB）治疗的核因子-κB配体受体激活剂（RANKL）的人源化单克隆抗体，地诺塞麦对肿瘤基质细胞的抗肿瘤作用有限。然而，其作用机制尚未明确。先前的研究表明，p62可能在狄诺塞麦的抗肿瘤活性中发挥重要作用。该研究旨在探讨狄诺塞麦抑制GCTB肿瘤基质细胞生长的机制是否是通过p62调节和其他相关机制。p62在治疗前后的表达情况通过 RT-qPCR、蛋白质印迹、ELISA 和免疫组织化学分析对狄诺塞麦治疗进行了分析。从新鲜GCTB肿瘤组织（L细胞）和转移组织（M细胞）中分离出两种原代肿瘤基质细胞。在体外研究短发夹 RNA 慢病毒转染的 p62 敲低肿瘤基质细胞中的细胞增殖、迁移、凋亡和自噬。在体内鸡绒毛尿囊膜模型中评估肿瘤生长。发现狄诺塞麦治疗后 p62 表达下调。 p62表达降低的患者无复发生存率较低。 M 细胞的增殖不受地诺塞麦治疗的抑制，但通过 p62 敲除可恢复。此外，p62敲低可抑制体内肿瘤生长。狄诺塞麦诱导 M 细胞凋亡并在 G1/G0 转变时阻止细胞周期，并且 p62 敲低也增强了这些作用。自噬通量测定显示，狄诺塞麦孵育后，p62 调节依赖于自噬。狄诺塞麦通过依赖于自噬途径的 p62 下调，诱导肿瘤基质细胞凋亡。对于 GCTB 靶向治疗，p62 和 RANKL 敲低的组合可能是比单独 RANKL 敲低更好的策略。版权所有 © Bentham Science Publishers；如有任何疑问，请发送电子邮件至 epub@benthamscience.net。

As the only humanized monoclonal antibody against receptor activator of nuclear factor-κB ligand (RANKL) for giant cell tumour of bone (GCTB) therapy, denosumab has limited antitumour effect on neoplastic stromal cells. Nevertheless, its mechanism of action has not yet been clarified. A previous study has revealed that p62 may play an important role in the antitumour activity of denosumab.The study aimed to investigate if the mechanism by which denosumab inhibits GCTB neoplastic stromal cells growth is via p62 modulation and other related mechanisms.p62 expression before and after denosumab therapy was analysed by RT‒qPCR, western blot, ELISA, and immunohistochemical assays. Two primary neoplastic stromal cells were isolated from fresh GCTB tumour tissue (L cell) and metastatic tissue (M cell). Cell proliferation, migration, apoptosis, and autophagy were investigated in p62 knockdown neoplastic stromal cells transfected by short hairpin RNA lentivirus in vitro. Tumor growth was evaluated in the chick chorioallantoic membrane model in vivo.p62 expression was found to be downregulated following denosumab therapy. The patients with a decrease in p62 expression had lower recurrence-free survival rates. The proliferation of M cells was not inhibited by denosumab therapy, but it was restored by p62 knockdown. Moreover, p62 knockdown inhibited tumour growth in vivo. Denosumab induced M cell apoptosis and arrested the cell cycle at the G1/G0 transition and these effects were also enhanced by p62 knockdown. Autophagic flux assays revealed p62 modulation to be dependent on autophagy following denosumab incubation.Denosumab induced neoplastic stromal cells apoptosis via p62 downregulation dependent on autophagy pathway. The combination of p62 and RANKL knockdown might be a better strategy than RANKL knockdown alone for GCTB targeted therapy.Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.