STAT1 modification improves therapeutic effects of interferons on lung cancer cells.
BACKGROUND
Interferons (IFNs) have potent anti-proliferative, pro-apoptotic, and immunomodulatory activities against cancer. However, the clinical utility of IFNs is limited by toxicity and pharmacokinetics making it difficult to achieve sustained therapeutic levels especially in solid tumors.


METHODS
Signal Transducer and Activator of Transcription 1 (STAT1) or a modified STAT1 (designated STAT1-CC) that is hyper-responsive to IFN were overexpressed in lung cancer SPC-A-1 and H1299 cells using lentiviral vectors. Transduction efficiency was monitored using enhanced green fluorescent protein (EGFP) expression. After transduction, cells were treated with interferon-gamma (IFN-γ) or interferon-beta (IFN-β) and monitored for cell proliferation, migration, and invasiveness using Cell Counting Kit-8 and transwell chamber assays and for apoptosis using Annexin V detection by flow cytometry. In addition, levels of STAT1, STAT1 Tyr-701 phosphorylation (pSTAT1), fibronectin, and β-catenin were determined using western blotting. In the case of IFN-γ stimulation, levels of S100A4, proliferating cell nuclear antigen (PCNA), and c-fos expression were also determined.


RESULTS
We found that expression of STAT1 or STAT1-CC enhanced the effect of IFN-γ and, IFN-β on inhibition of human lung cancer cell proliferation, migration and invasiveness. Moreover, STAT1 and STAT1-CC expression caused increases in pSTAT1 and decreases in fibronectin and β-catenin levels. STAT1-CC showed increased effects compared to STAT1 on IFN-γ induced pSTAT1 and down-regulation of S100A4, PCNA, and c-fos levels.


CONCLUSIONS
The results show that STAT1-CC exhibited more strength in improving the antitumor response of IFNs in lung cancer cells. Results from this study suggest that combined treatment of IFNs and STAT1-CC might be a feasible approach for the clinical management of lung cancer in the future.
Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, Zhejiang, China. jiestory414@163.com.
Junjie
J
Chen
Department of Pulmonary Medicine, Lishui Central Hospital, The Fifth Affiliated Hospital of Wenzhou Medical University, Lishui Hospital of Zhejiang University, Lishui, Zhejiang, China. zhaojialu521@126.com.
Jialu
J
Zhao
Department of Neurosurgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China. chenlefu915@163.com.
Lefu
L
Chen
Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, Zhejiang, China. 154598090@qq.com.
Nian
N
Dong
Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, Zhejiang, China. yingzj0577@126.com.
Zhaojian
Z
Ying
Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, Zhejiang, China. 670775624@qq.com.
Zhenzhen
Z
Cai
Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, Zhejiang, China. 251354702@qq.com.
Dongxiang
D
Ji
Drug Discovery Program, Pulmonary and Critical Care Medicine, Department of Medicine, Washington University, St. Louis, MO, USA. yzhang@dom.wustl.edu.
Yong
Y
Zhang
Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, Zhejiang, China. conniejs1984@163.com.
Li
L
Dong
Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, Zhejiang, China. wzliyp@163.com.
Yuping
Y
Li
Central Laboratory, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China. jiangleistone79@163.com.
Lei
L
Jiang
Drug Discovery Program, Pulmonary and Critical Care Medicine, Department of Medicine, Washington University, St. Louis, MO, USA. holtzmanm@wustl.edu.
Michael J
MJ
Holtzman
Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, 325000, Zhejiang, China. chenchengshui@126.com.
Chengshui
C
Chen
D000970:Antineoplastic Agents / Q000627:therapeutic use; D017209:Apoptosis; D045744:Cell Line, Tumor; D002465:Cell Movement; D049109:Cell Proliferation; D002470:Cell Survival; D005353:Fibronectins / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic; D049452:Green Fluorescent Proteins / Q000737:chemistry; D057809:HEK293 Cells; D006801:Humans; D016899:Interferon-beta / Q000494:pharmacology; D007371:Interferon-gamma / Q000494:pharmacology; D008175:Lung Neoplasms / Q000188:drug therapy / Q000378:metabolism*; D009361:Neoplasm Invasiveness; D009362:Neoplasm Metastasis; D010766:Phosphorylation; D050794:STAT1 Transcription Factor / Q000737:chemistry* / Q000235:genetics*; D051176:beta Catenin / Q000378:metabolism
D000970:Antineoplastic Agents; D005353:Fibronectins; D050794:STAT1 Transcription Factor; C494079:STAT1 protein, human; D051176:beta Catenin; D049452:Green Fluorescent Proteins; D016899:Interferon-beta; D007371:Interferon-gamma