High Throughput Screening of Biomarkers for Oral Squamous Cell Carcinoma

Objectives: High throughput screening of methylation profiling of oral squamous cell carcinoma (OSCC) screened by DNA methylation microarray, followed by validation of methylation statuses of significant candidate genes using methylation specified polymerase chain reaction (MSPCR). Finally, OSCC prognostic values were also conducted on demographic and clinicopathological data with promoter hypermethylated genes of OSCC.  Methods:  Normal oral mucosa and OSCC tissues were analysed using methylation microarray. The selected differential hypermethylated genes from microarray profiling were further verified for their methylation status. Lastly, relations of demographic and clinicopathological characteristics and these signature genes were conducted for prognostic purposes of OSCC.  Results: 91 of promoter hypermethylated and 85 hypomethylated genes have been screened using methylation microarray. High frequencies of promoter hypermethylation of clinical samples were found in genes of PIKCR3, TP73, MEF2D, RRM2 and CELSR3 by MSPCR analysis. In addition, significant associations were found between TP73 hypermethylation with patients’ tumour site (p=0.006), and CELSR3 and TP73 hypermethylation with patients’ invasive stages (p=0.008 and 0.025). Conclusions: High throughput screening using DNA methylation profiling revealed potential diagnostic and prognostic biomarkers for OSCC in this study. The results also provide a new insight into the molecular basis of promoter hypermethylation in OSCC.