Abstract
Background: LncRNA NBR2 is a key regulator in cancer metabolism. However, its role in lung cancer is unknown.
Objective: This study aimed to explore the function of NBR2 in non-small cell lung cancer (NSCLC), which is the most common type of lung cancer.
Methods: Paired NSCLC and non-cancer tissues were collected from 68 patients with NSCLC. The expression of NBR2 and transforming growth factor-β1 (TGF-β1) in these samples was analyzed by RT-qPCR. The prognostic value of NBR2 for NSCLC was explored by performing a 5-year follow-up study. The interaction between NBR2 and TGF-β1 in two NSCLC cell lines was detected by overexpression assay, followed by RT-qPCR and Western blot analysis. Flow cytometry was performed to evaluate the role of NBR2 and TGF-β1 in regulating NSCLC cell stemness.
Results: NBR2 was significantly downregulated in NSCLC tissues than that in non-cancer tissues of NSCLC patients, and low expression levels of NBR2 predicted poor survival. TGF-β1 was significantly upregulated in NSCLC tissues than that in non-cancer tissues, and was inversely correlated with NBR2. Overexpression of NBR2 downregulated TGF-β1, while overexpression of TGF-β1 did not affect the expression of NBR2. Overexpression of NBR2 inhibited, while overexpression of TGF-β1 promoted NSCLC cell stemness. Overexpression of TGF-β1 attenuated the effects of overexpression of NBR2. Mechanically, NBR2 interacted with Notch1 protein to inhibit its expression, thereby inhibiting the expression of TGF-β1 and further affecting the proportion of CD133+ cells.
Conclusion: LncRNA NBR2 regulates cancer cell stemness and predicts survival in NSCLC possibly by downregulating TGF-β1 through Notch1.
Keywords: non-small cell lung cancer, lncRNA NBR2, TGF-β1, stemness
[http://dx.doi.org/10.3322/caac.21387] [PMID: 28055103]
[http://dx.doi.org/10.1093/annonc/mdw326] [PMID: 27664245]
[http://dx.doi.org/10.1038/sj.bjc.6605399]
[http://dx.doi.org/10.1007/978-3-319-24223-1_1]
[http://dx.doi.org/10.1136/bmjopen-2015-009419]
[http://dx.doi.org/10.1146/annurev.med.54.101601.152202] [PMID: 12471176]
[http://dx.doi.org/10.1016/j.soc.2011.07.003] [PMID: 21986260]
[http://dx.doi.org/10.4161/rna.20481]
[http://dx.doi.org/10.1038/onc.2011.621]
[http://dx.doi.org/10.1016/j.ccell.2016.03.010]
[http://dx.doi.org/10.1038/modpathol.2012.160] [PMID: 22996375]
[http://dx.doi.org/10.1038/ncb3328]
[http://dx.doi.org/10.3892/ol.2012.928]
[http://dx.doi.org/10.1080/15384101.2016.1249545]
[http://dx.doi.org/10.1155/2015/587193]
[http://dx.doi.org/10.1002/jcb.27508] [PMID: 30187965]
[http://dx.doi.org/10.1186/s13046-017-0664-4]
[http://dx.doi.org/10.1016/j.pharmthera.2014.11.001] [PMID: 25444759]
[http://dx.doi.org/10.1038/ncomms2039] [PMID: 22968701]
[http://dx.doi.org/10.1002/ijc.28520] [PMID: 24155219]
[http://dx.doi.org/10.1002/ijc.31605] [PMID: 29761481]