Department of Ophthalmology, Clinic for Stem Cell Transplantation, University Hospital Hamburg-Eppendorf, Hamburg, Germany.
Melanoma Res. 2011 Oct;21(5):405-16. doi: 10.1097/CMR.0b013e328348db10.
'Cancer stem cells' (CSCs) are tumor cells with stem cell properties hypothesized to be responsible for tumorigenesis, metastatis, and resistance to treatment, and have been identified in different tumors including cutaneous melanoma, using stem cell markers such as CD133. This study explored expression of CD133 and other putative stem cell markers in uveal melanoma. Eight uveal melanoma cell lines were subjected to flow-cytometric (fluorescence-activated cell sorting) analysis of CD133 and other stem cell markers. Eight paraffin-embedded tumors were analyzed by immunohistochemistry for CD133, Pax6, Musashi, nestin, Sox2, ABCB5, and CD68 expressions. Ocular, uveal melanoma, and hematopoietic stem cell distributions of C-terminal and N-terminal CD133 mRNA splice variants were compared by reverse-transcription PCR. Fluorescence-activated cell sorting analysis revealed a population of CD133-positive/nestin-positive cells in cell lines Mel270, OMM 2.3, and OMM2.5. All cell lines studied were positive for nestin, CXCR-4, CD44, and c-kit. Immunohistochemistry identified cells positive for CD133, Pax6, Musashi, nestin, Sox2, ABCB5, and CD68 predominantly at the invading tumor front. C-terminal primers interacting with CD133 splice variant s2 detected a novel variant lacking exon 27. Differential expression of CD133 splice variants was found in iris, ciliary body, retina, and retinal pigment epithelium/choroid as well as in uveal melanoma cell lines. mRNA for nestin, Sox2, and Musashi was present in all studied cell lines. Uveal melanoma such as cutaneous melanoma may therefore contain CSCs. Further experiments are needed to isolate stem cell marker-positive cells, to evaluate their functional properties and to explore therapeutical approaches to these putative CSCs in uveal melanoma.
'癌症干细胞'（CSC）是具有干细胞特性的肿瘤细胞，被假设为肿瘤发生、转移和治疗抵抗的原因，并已在不同的肿瘤中被识别，包括皮肤黑色素瘤，使用干细胞标志物如 CD133。本研究探讨了葡萄膜黑色素瘤中 CD133 和其他假定干细胞标志物的表达。对 8 种葡萄膜黑色素瘤细胞系进行了 CD133 和其他干细胞标志物的流式细胞术（荧光激活细胞分选）分析。对 8 例石蜡包埋的肿瘤进行了 CD133、Pax6、Musashi、巢蛋白、Sox2、ABCB5 和 CD68 表达的免疫组织化学分析。通过逆转录 PCR 比较了 C 端和 N 端 CD133 mRNA 剪接变体的 C 端和 N 端 CD133 mRNA 剪接变体在眼部、葡萄膜黑色素瘤和造血干细胞中的分布。荧光激活细胞分选分析显示，在细胞系 Mel270、OMM 2.3 和 OMM2.5 中存在 CD133 阳性/巢蛋白阳性细胞群。所有研究的细胞系均为巢蛋白、CXCR-4、CD44 和 c-kit 阳性。免疫组织化学鉴定出 CD133、Pax6、Musashi、巢蛋白、Sox2、ABCB5 和 CD68 阳性细胞主要位于侵袭性肿瘤前缘。与 CD133 剪接变体 s2 相互作用的 C 端引物检测到一种缺乏外显子 27 的新型变体。在虹膜、睫状体、视网膜和视网膜色素上皮/脉络膜以及葡萄膜黑色素瘤细胞系中发现了 CD133 剪接变体的差异表达。所有研究的细胞系均存在 nestin、Sox2 和 Musashi 的 mRNA。因此，葡萄膜黑色素瘤，如皮肤黑色素瘤，可能含有 CSC。需要进一步的实验来分离干细胞标志物阳性细胞，评估它们的功能特性，并探索针对葡萄膜黑色素瘤中这些假定的 CSC 的治疗方法。
