STAT3 的过表达增强了非小细胞肺癌（NSCLC）细胞的生长、存活和放射抵抗能力。

Overexpression of STAT3 potentiates growth, survival, and radioresistance of non-small-cell lung cancer (NSCLC) cells.

机构信息

Department of Respiratory Medicine, Tangdu Hospital, Fourth Military Medical University, Xi'an, Shaanxi Province, China.

出版信息

J Surg Res. 2011 Dec;171(2):675-83. doi: 10.1016/j.jss.2010.03.053. Epub 2010 Apr 18.

DOI:10.1016/j.jss.2010.03.053

PMID:20605584

Abstract

OBJECTIVE

Activation of signal transducer and activator of transcription 3 (STAT3) play important roles in tumorigenesis and tumor progression. The overexpression of STAT3 has been found in various malignancies including non-small-cell lung carcinoma (NSCLC). The purpose of this study was to explore the correlation between overexpression of STAT3 gene and growth, survival, and radiosensitivity of NSCLC cells.

METHODS

Subclones using vector-based short hairpin RNA (shRNA) were established. RT-PCR and Western blot assays were performed to detect the expression of STAT3 mRNA and protein in untransfected or stably transfected NSCLC cells. Then, MTT and soft agar colony assays were performed to determine the effect of STAT3 inhibition on in vitro growth of NSCLC cells. Hoechst staining assay was performed to analyze the effect of STAT3 inhibition on apoptosis of NSCLC cells. Additionally, clonogenic survival assays were performed to detect the effect of STAT3 inhibition on in vitro radiosensitivity of NSCLC cells. Finally, to examine the effect of pSUPER-shSTAT3 on proliferation and radiosensitivity in vivo, a subcutaneous (s.c.) tumor formation assay in nude mice was performed.

RESULTS

We successfully established two stable transfected cell lines (A549/shSTAT3 and SK-MES-1/shSTAT3) in which the expression of STAT3 mRNA and protein was down-regulated. Those two stable subclones showed a significantly dramatic reduction in colony-forming ability and proliferation not only in vitro but also in vivo. The apoptotic rates of A549/shSTAT3 and SK-MES-1/shSTAT3 cells increased to 19.2% and 16.4%, respectively. Moreover, shRNA-mediated STAT3 inhibition could also significantly enhance radiosensitivity of NSCLC cells both in vitro and in vivo.

CONCLUSION

Together, the overexpression of STAT3 is correlated with growth, survival, and radioresistance of NSCLC cells, and STAT3 might be a molecular therapeutic target for gene therapy or radiosensitization of NSCLC.

摘要

目的

信号转导和转录激活因子 3（STAT3）的激活在肿瘤发生和肿瘤进展中起着重要作用。STAT3 的过表达已在各种恶性肿瘤中发现，包括非小细胞肺癌（NSCLC）。本研究旨在探讨 STAT3 基因过表达与 NSCLC 细胞生长、存活和放射敏感性的相关性。

方法

使用基于载体的短发夹 RNA（shRNA）建立亚克隆。未转染或稳定转染 NSCLC 细胞中 STAT3 mRNA 和蛋白的表达通过 RT-PCR 和 Western blot 检测。然后，MTT 和软琼脂集落测定用于确定 STAT3 抑制对 NSCLC 细胞体外生长的影响。Hoechst 染色法用于分析 STAT3 抑制对 NSCLC 细胞凋亡的影响。此外，集落形成存活测定用于检测 STAT3 抑制对 NSCLC 细胞体外放射敏感性的影响。最后，为了研究 pSUPER-shSTAT3 对体内增殖和放射敏感性的影响，在裸鼠中进行了皮下（s.c.）肿瘤形成测定。

结果

我们成功建立了两个稳定转染的细胞系（A549/shSTAT3 和 SK-MES-1/shSTAT3），其中 STAT3 mRNA 和蛋白的表达下调。这两个稳定的亚克隆显示出明显的集落形成能力和增殖能力下降，不仅在体外，而且在体内也是如此。A549/shSTAT3 和 SK-MES-1/shSTAT3 细胞的凋亡率分别增加到 19.2%和 16.4%。此外，shRNA 介导的 STAT3 抑制还可以显著增强 NSCLC 细胞的放射敏感性，无论是在体外还是体内。