1 Department of Surgery, Medical University of Vienna, Vienna, Austria ; 2 Oncologic Respiratory Unit, Otto-Wagner Hospital, Vienna, Austria.
Transl Lung Cancer Res. 2016 Feb;5(1):71-7. doi: 10.3978/j.issn.2218-6751.2015.12.12.
Small cell lung cancer (SCLC) is an aggressive and invasive variant of lung tumors. SCLC, especially in advanced stages, is distinguished by extremely high numbers of circulating tumor cells (CTCs) in comparison to other malignancies. CTCs are operative in tumor spread and are currently enumerated to assess prognosis and response to cytotoxic therapy. Chemosensitivity of SCLC CTCs compared to primary tumors and metastases is not known.
Establishment of two SCLC CTC cell lines, namely BHGc7 and BHGc10, allowed the in vitro characterization of their chemosensitivity to the second-line chemotherapeutics topotecan and epirubicin in comparison to a range of SCLC cell lines.
The SCLC CTC cell lines exhibited an approximately 7- and 12-fold increased chemosensitivity to epirubicin compared to topotecan, respectively, in in vitro cytotoxicity assays. In comparison to a panel of six SCLC cell lines, the two CTC lines showed a significantly higher chemosensitivity to epirubicin (range, 3- to 16-fold) and topotecan (range, 2.2- to 14.4-fold), respectively.
CTC cell lines derived from SCLC patients with recurrent disease exhibit high chemosensitivity to epirubicin vs. topotecan and show considerable more cytotoxicity in response to both compounds in comparison to a panel of SCLC cell lines. Thus, a decrease in the number of CTCs in response to second-line chemotherapy in SCLC patients may overestimate the effect on resident SCLC lesions and metastases.
小细胞肺癌（SCLC）是一种侵袭性和侵袭性的肺肿瘤变体。与其他恶性肿瘤相比，SCLC，尤其是晚期，其循环肿瘤细胞（CTC）数量极高。CTC 参与肿瘤扩散，目前用于评估预后和对细胞毒性治疗的反应。SCLC CTC 相对于原发性肿瘤和转移灶的化疗敏感性尚不清楚。
建立了两种 SCLC CTC 细胞系，即 BHGc7 和 BHGc10，允许对其体外对二线化疗药物拓扑替康和表柔比星的化疗敏感性进行体外特征分析，并与一系列 SCLC 细胞系进行比较。
在体外细胞毒性测定中，SCLC CTC 细胞系对表柔比星的敏感性分别比拓扑替康增加了约 7 倍和 12 倍。与六株 SCLC 细胞系相比，两种 CTC 系对表柔比星（范围为 3 至 16 倍）和拓扑替康（范围为 2.2 至 14.4 倍）的化疗敏感性明显更高。
从复发性疾病的 SCLC 患者中分离出的 CTC 细胞系对表柔比星与拓扑替康的化疗敏感性较高，与 SCLC 细胞系相比，对这两种化合物的反应均具有更高的细胞毒性。因此，二线化疗后 SCLC 患者 CTC 数量的减少可能高估了对常驻 SCLC 病变和转移灶的影响。
