Department of Biochemistry, Osaka International Cancer Institute, Osaka, Japan; Department of Obstetrics and Gynecology, Osaka University Graduate School of Medicine, Suita, Japan.
Department of Biochemistry, Osaka International Cancer Institute, Osaka, Japan; Department of Clinical Bio-resource Research and Development, Graduate School of Medicine Kyoto University, Kyoto, Japan; Department of Obstetrics and Gynecology, Osaka University Graduate School of Medicine, Suita, Japan.
Biochem Biophys Res Commun. 2020 Apr 2;524(2):398-404. doi: 10.1016/j.bbrc.2020.01.024. Epub 2020 Jan 30.
Neuroendocrine carcinoma of small cell type (SCNEC) is a rare pathological subtype in cervical cancer, which has a worse prognosis than other histological cell types. Due to its low incidence and the lack of experimental platforms, the molecular characteristics of SCNEC in the cervix remain largely unknown. Using the cancer tissue-originated spheroid (CTOS) method-an ex vivo 3D culture system that preserves the differentiation status of the original tumors-we established a panel of CTOS lines of SCNEC. We demonstrated that xenograft tumors and CTOSs, respectively, exhibited substantial intra-tumor and intra-CTOS variation in the expression levels of chromogranin A (CHGA), a neuroendocrine tumor marker. Since hypoxia affects differentiation in various tumors and in stem cells, we also investigated how hypoxia affected neuroendocrine differentiation of SCNEC of the uterine cervix. In the CTOS line cerv21, hypoxia suppressed expression of the neuroendocrine markers CHGA and synaptophysin (SYP). Flow cytometry analysis using CD99 (a membrane protein marker of SCNEC) revealed decreased CD99 expression in a subset of cells under hypoxic conditions. These expression changes were attenuated by HIF-1α knockdown, and by a Notch inhibitor, suggesting that these molecules played a role in the regulation of neuroendocrine differentiation. The examined SCNEC markers were suppressed under hypoxia in multiple CTOS lines. Overall, our present results indicated that neuroendocrine differentiation in SCNEC of the uterus is a variable phenotype, and that hypoxia may be one of the factors regulating the differentiation status.
小细胞神经内分泌癌（SCNEC）是宫颈癌中一种罕见的病理亚型，其预后比其他组织学细胞类型差。由于其发病率低，且缺乏实验平台，因此宫颈 SCNEC 的分子特征在很大程度上仍不清楚。我们使用肿瘤组织起源的球体（CTOS）方法-一种保留原始肿瘤分化状态的体外 3D 培养系统-建立了一组 SCNEC 的 CTOS 系。我们证明，异种移植肿瘤和 CTOS 分别在神经内分泌肿瘤标志物嗜铬粒蛋白 A（CHGA）的表达水平上表现出显著的肿瘤内和 CTOS 内变异性。由于缺氧会影响各种肿瘤和干细胞的分化，我们还研究了缺氧如何影响子宫颈 SCNEC 的神经内分泌分化。在 CTOS 系 cerv21 中，缺氧抑制了神经内分泌标志物 CHGA 和突触素（SYP）的表达。使用 CD99（SCNEC 的膜蛋白标志物）进行的流式细胞术分析显示，在缺氧条件下，一部分细胞的 CD99 表达减少。这些表达变化被 HIF-1α 敲低和 Notch 抑制剂减弱，表明这些分子在调节神经内分泌分化中起作用。在多个 CTOS 系中，检查的 SCNEC 标志物在缺氧下受到抑制。总的来说，我们目前的结果表明，子宫 SCNEC 的神经内分泌分化是一种可变性表型，而缺氧可能是调节分化状态的因素之一。
