Division in Anatomy and Developmental Biology, Department of Oral Biology, Oral Science Research Center, BK21 FOUR Project, Yonsei University College of Dentistry, Seoul, Korea.
Department of Oral & Maxillofacial Surgery, Yonsei University, College of Dentistry, Seoul, Korea.
Cell Prolif. 2021 Jul;54(7):e13073. doi: 10.1111/cpr.13073. Epub 2021 Jun 6.
The treatment of ameloblastoma, an odontogenic epithelial tumour destroying jawbone, mainly depends on radical destructive resections. Other therapeutic options are limited by the characteristics of ameloblastoma, such as high recurrence rates and resistance to radiation and chemotherapy, which implies possible existence of cancer stem cells (CSCs) in ameloblastoma. Here, we identified a putative CSC population in immortalized and primary human ameloblastoma cells and examined possible therapeutic reagents to reduce the CSC population.
We investigated subpopulations of AM-1 cell line and human ameloblastoma cells using immunocytochemistry and flow cytometry and the effects of Wnt signalling activators on the 2- and 3-dimensional cultured ameloblastoma cells using molecular biological analyses.
Among heterogenous ameloblastoma cells, small-sized and round-shaped cells were found to be proliferative and expressed a marker of dental epithelial stem cells, SRY-box 2 (Sox2). Exogenous activation of Wnt signalling using glycogen synthase kinase 3β inhibitors, lithium chloride (LiCl) and valproic acid (VPA), increased the cell size and decreased proliferation of cells and expression of Sox2 in 2 dimensionally cultured AM-1 and human primary ameloblastoma cells. Furthermore, the growth of 3 dimensionally cultured AM-1 cells as suspended or embedded in gel was suppressed by treatment with Wnt signalling activators, VPA and CHIR99021, or antibodies to sclerostin, an antagonist of Wnt signalling.
We suggest that Wnt signalling activators are potential drug candidates to suppress CSCs in ameloblastoma.
成釉细胞瘤是一种破坏颌骨的牙源性上皮肿瘤，其主要治疗方法依赖于根治性破坏性切除术。其他治疗选择受到成釉细胞瘤特征的限制，如高复发率以及对放疗和化疗的耐药性，这意味着成釉细胞瘤中可能存在癌症干细胞（CSC）。在这里，我们在永生化和原代人成釉细胞瘤细胞中鉴定出一个假定的 CSC 群体，并研究了可能减少 CSC 群体的治疗试剂。
我们使用免疫细胞化学和流式细胞术研究 AM-1 细胞系和人成釉细胞瘤细胞的亚群，并使用分子生物学分析研究 Wnt 信号激活剂对 2 维和 3 维培养的成釉细胞瘤细胞的影响。
在异质成釉细胞瘤细胞中，发现小尺寸圆形细胞具有增殖能力，并表达牙上皮干细胞标志物 Sry 盒 2（Sox2）。使用糖原合成酶激酶 3β抑制剂氯化锂（LiCl）和丙戊酸（VPA）外源激活 Wnt 信号，增加了二维培养的 AM-1 和人原代成釉细胞瘤细胞的细胞大小，降低了细胞增殖和 Sox2 的表达。此外，Wnt 信号激活剂 VPA 和 CHIR99021 或抗骨硬化蛋白抗体处理抑制了 3 维培养的 AM-1 细胞作为悬浮或嵌入凝胶中的生长，骨硬化蛋白是 Wnt 信号的拮抗剂。
我们认为 Wnt 信号激活剂是抑制成釉细胞瘤 CSC 的潜在候选药物。
