MCRS1 overexpression, which is specifically inhibited by miR-129*, promotes the epithelial-mesenchymal transition and metastasis in non-small cell lung cancer

Min-Xia Liu, Ke-Cheng Zhou, Yi Cao
Molecular Cancer 2014, 13: 245

BACKGROUND: Although tumor invasion and metastasis are both classical hallmarks of cancer malignancy and the major causes of poor clinical outcomes among cancer patients, the underlying master regulators of invasion and metastasis remain largely unknown. In this study, we observed that an overexpression of microspherule protein 1 (MCRS1) promotes the invasion and metastasis of non-small cell lung cancer (NSCLC) cells. Furthermore, we sought to systematically investigate the pathophysiological functions and related mechanisms of MCRS1.

METHODS: Retrovirus-mediated RNA interference was employed to knockdown MCRS1 expression in NSCLC cell lines. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot respectively were used to measure levels of mRNA and protein. Further cell permeability assessment, invasion and proliferation assays were conducted to evaluate MCRS1 functions in vitro while nude mice experiments were performed to examine metastatic capability in vivo. Microarray analysis and microRNA (miRNA) sequencing were respectively carried out for mRNA and miRNA expression profiling, while chromatin immunoprecipitation (ChIP), luciferase reporter assay, and miRNA transfection were used to investigate the interaction between MCRS1 and miRNAs.

RESULTS: MCRS1 knockdown induced morphological alterations, increased monolayer integrity, decreased cellular invasion and metastasis, and attenuated stemness and drug resistance among tested NSCLC cells. The levels of MCRS1 expression were likewise correlated with tumor metastasis among NSCLC patients. We identified differentially expressed genes after MCRS1 silencing, which included cell junction molecules, such as ZO-1, Occludin, E-cadherin, and DSG2. However, these differentially expressed genes were not directly recognized by a transcriptional complex containing MCRS1. Furthermore, we found that MCRS1 binds to the miR-155 promoter and regulates its expression, as well as MCRS1 promotes epithelial-mesenchymal transition (EMT), invasion, and metastasis through the up-regulation of miR-155. Systematic investigations ultimately showed that MCRS1 was directly and negatively regulated by the binding of miR-129* to its 3'-UTR, with miR-129* overexpression suppressing the growth and invasion of NSCLC cells.

CONCLUSIONS: MiR-129* down-regulation induced MCRS1 overexpression, which promotes EMT and invasion/metastasis of NSCLC cells through both the up-regulation of miR-155 and down-regulation of cell junction molecules. This miR-129*/MCRS1/miR-155 axis provides a new angle in understanding the basis for the invasion and metastasis of lung cancer.

Full Text Links

Find Full Text Links for this Article


You are not logged in. Sign Up or Log In to join the discussion.

Related Papers

Remove bar
Read by QxMD icon Read

Save your favorite articles in one place with a free QxMD account.


Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"