UNASSIGNED: The relationship between DDX58 expression and breast cancer prognosis was investigated by online clinical databases and confirmed by immunohistochemistry analysis. DDX58 was knockout by CRISPR-Cas9 system (DDX58-KO), knockdown by DDX58-siRNA (DDX58-KD), and stably over expressed (DDX58-OE) by lentivirus. Western blotting, immunofluorescence and qPCR were used for related molecules detection. Apoptosis was analyzed through flow cytometry (Annexin V/7AAD apoptosis assay) and Caspase 3/7 activity assay.
UNASSIGNED: Patients with lower expression of DDX58 led to lower rate of pathological complete response (pCR) and worse prognosis by online databases and hospital clinical data. DDX58-KD cells showed multiple chemo-drugs resistance (paclitaxel, doxorubicin, 5-fluorouracil) in TNBC cell lines. Similarly, DDX58-KO cells also showed multiple chemo-drugs resistance in a dosage-dependent manner. In the CDX model, tumours in the DDX58-KO group had a 25% reduction in the tumour growth inhibition rate (IR) compared to wild-type (WT) group after doxorubicin (Dox) treatment. The depletion of DDX58 inhibited proliferation and promoted the migration and invasion in MDA-MB-231 cells. The findings of our research indicated that DDX58-KO cells exhibit a reduction in Dox-induced apoptosis both in vivo and in vitro. Mechanistically, Dox treatment leads to a significant increase in the expression of double-stranded RNAs (dsRNAs) and activates the DDX58-Type I interferon (IFN) signaling pathway, ultimately promoting apoptosis in TNBC cells.
UNASSIGNED: In the process of TNBC chemotherapy, the deficiency of DDX58 can inhibit Dox-induced apoptosis, revealing a new pathway of chemotherapy resistance, and providing a possibility for developing personalized treatment strategies based on DDX58 expression levels.
■通过在线临床数据库研究DDX58表达与乳腺癌预后之间的关系,并通过免疫组织化学分析证实。DDX58被CRISPR-Cas9系统(DDX58-KO)敲除,DDX58-siRNA(DDX58-KD)并且通过慢病毒稳定过表达(DDX58-OE)。西方印迹,免疫荧光和qPCR用于相关分子检测。通过流式细胞术(膜联蛋白V/7AAD细胞凋亡测定)和Caspase3/7活性测定分析细胞凋亡。
■根据在线数据库和医院临床数据,DDX58表达较低的患者病理完全缓解率(pCR)较低,预后较差。DDX58-KD细胞显示多种化疗药物耐药(紫杉醇,阿霉素,5-氟尿嘧啶)在TNBC细胞系中。同样,DDX58-KO细胞也以剂量依赖性方式显示多种化疗药物抗性。在CDX模型中,与多柔比星(Dox)治疗后的野生型(WT)组相比,DDX58-KO组的肿瘤生长抑制率(IR)降低了25%。DDX58的清除抑制MDA-MB-231细胞的增殖,促进细胞的迁移和侵袭。我们的研究结果表明,DDX58-KO细胞在体内和体外均表现出Dox诱导的凋亡减少。机械上,Dox处理导致双链RNA(dsRNA)的表达显着增加,并激活DDX58-I型干扰素(IFN)信号通路,最终促进TNBC细胞凋亡。
■在TNBC化疗过程中,DDX58的缺乏可以抑制Dox诱导的细胞凋亡,揭示了化疗耐药的新途径,并为开发基于DDX58表达水平的个性化治疗策略提供了可能性。