Scientific Reports 4, Article number: 6331 (2014); Published: 11 September 2014; Updated: 21 November 2014

Huibin Liu was omitted from the author list in the original version of this Article.

The Author Contribution Statement should read ‘D.M. and C.Y.J. conceived, designed and carried out the experiments, analysed the experimental data and wrote the paper; X.L.H. and H.B.L. guided the experiments and prepared figures 1-2 and tables 1-4; Q.Z.L. co-performed clinical samples collections and DNA extraction experiments; T.T.L. and Y.Y.Y. co-performed methylation-specific PCR experiments; O.L. supervised and directed the project. All authors discussed the results and commented on the manuscript and reviewed the manuscript.’

This has now been corrected in the PDF and HTML versions of the Article.