Abstract：
Cancer stem cells (CSCs) play pivotal roles in the growth, invasion, metastasis, chemo-resistance in malignant peripheral nerve sheath tumor (MPNST). The current characterization of CSCs in MPNST is not complete. Decorin is a critical regulator of microenvironment, but its expression and function in CSCs of MPNST has not been studied. In the current study, Decorin levels and its relationship with lung and liver metastasis were determined in clinical specimens. Decorin expression in CD133-positive or CD44-positive CSCs was analyzed by RT-qPCR on cytospun MPNST cells after flow cytometry-based cell sorting. Decorin-positive cells were separated from Decorin-negative cells in transfected MPNST cell lines using a designed plasmid expressing red fluorescent protein (RFP) under a Decorin promoter. Tumor sphere formation, tumor growth, cell invasion, cell migration, and the resistance to chemotherapy-induced apoptosis were determined on Decorin-positive versus Decorin-negative MPNST cells. In vivo tumor growth was analyzed in mice receiving subcutaneous transplantation of Decorin-positive versus Decorin-negative MPNSTs. We found that Decorin levels were significantly downregulated in MPNST specimens, compared to non-tumorous adjacent tissue. Significantly lower Decorin levels were detected in MPNSTs with lung or liver metastasis compared to those without. Poorer patient survival was detected in Decorin-low MPNST, compared to Decorin-high subjects. More Decorin-negative cells were detected in CD133-positive MPNST cells than CD133-negative MPNST cells, and in CD44-positive MPNST cells than in CD44-negative MPNST cells. Compared to Decorin-positive MPNST cells, Decorin-negative MPNST cells generated significantly more tumor spheres in culture, were more invasive and migratory, and were more resistant to chemotherapy-induced apoptosis, likely due to the inhibition of epidermal growth factor receptor signaling by Decorin. Decorin-negative MPNST cells grew significantly larger tumor in vivo. Thus, depletion of Decorin may occur in CSCs in MPNSTs, serving possibly as a new therapeutic target.
摘要：
肿瘤干细胞(CSCs)在肿瘤的生长过程中发挥着关键作用,入侵,转移,恶性周围神经鞘瘤（MPNST）的化学耐药性。目前MPNST中CSC的表征还不完整。Decorin是微环境的关键调节器，但其在MPNSTCSC中的表达和功能尚未被研究。在目前的研究中,在临床标本中确定了Decorin的水平及其与肺和肝转移的关系。在基于流式细胞术的细胞分选后,通过RT-qPCR在细胞纺丝MPNST细胞上分析CD133阳性或CD44阳性CSC中的Decorin表达。使用设计的在Decorin启动子下表达红色荧光蛋白（RFP）的质粒，在转染的MPNST细胞系中将Decorin阳性细胞与Decorin阴性细胞分离。肿瘤球形成，肿瘤生长，细胞入侵，细胞迁移，并确定了Decorin阳性与Decorin阴性MPNST细胞对化疗诱导的凋亡的抗性。在接受Decorin阳性与Decorin阴性MPNST的皮下移植的小鼠中分析体内肿瘤生长。我们发现在MPNST标本中Decorin水平显著下调,与非肿瘤邻近组织相比。与没有肺或肝转移的MPNSTs相比，在有肺或肝转移的MPNSTs中检测到明显较低的Decorin水平。在Decorin低MPNST中检测到较差的患者生存率，与Decorin高科目相比。在CD133阳性MPNST细胞中检测到的Decorin阴性细胞多于CD133阴性MPNST细胞，CD44阳性MPNST细胞高于CD44阴性MPNST细胞。与Decorin阳性MPNST细胞相比，Decorin阴性MPNST细胞在培养物中产生了更多的肿瘤球，更具侵入性和迁徙性，并且对化疗诱导的细胞凋亡更有抵抗力，可能是由于Decorin对表皮生长因子受体信号的抑制作用。Decorin阴性MPNST细胞在体内生长明显更大的肿瘤。因此，Decorin的耗尽可能发生在MPNST的CSC中，可能作为一个新的治疗靶点。
