Citing the potential for noninvasive tests capable of the early detection of head and neck cancer, researchers based at Queen Mary University in London announce that they have identified epigenetic changes in cancerous cells that are not seen in healthy cells. In particular, two genes (GLT8D1 and C6orf136) were found to be differentially expressed in head and neck squamous cell carcinomas (HNSCCs). Using methylation-specific quantitative PCR, the researchers confirmed that the promoters of GLT8D1 and C6orf136 were hypo- and hypermethylated, respectively, in HNSCC tissues.
The researchers published their results October 1 in the journal Cancer, in a paper entitled “Identification of FOXM1-induced epigenetic markers for head and neck squamous cell carcinomas.” In this paper, the researchers describe how they analyzed clinical specimens of malignant tissue from 93 cancer patients from Norway and the United Kingdom. These specimens were compared with either tissue donated by health individuals undergoing wisdom tooth extractions, or with noncancerous tissue from the same patients.
Lead researcher Muy Teck-Teh, M.D., from the Institute of Dentistry at Queen Mary, said: “In this study we have identified genes which were either over- or underexpressed in head and neck cancer. The expression of these genes was inversely correlated with particular DNA methylation marks, suggesting the genes are epigenetically modified in these cancers.”
Dr. Tuck-Teh said that these epigenetic markers could be clinically exploited as biomarkers for early precancer screening of head and neck cancer, but he also noted that further work would be needed, as his group's work is still in the discovery stage. At present, there is still no diagnostic test.
“The eventual aim would be to test asymptomatic patients and/or people with unknown mouth lesions,” added Dr. Tuck-Teh. “An advantage of epigenetic DNA markers is that it may be possible to measure them using noninvasive specimens. So it could enable the use of saliva, buccal scrapes, or blood serum for early cancer screening, diagnosis, and prognosis.”
Last year, in the International Journal of Cancer, researchers from Queen Mary University published a paper in which they described a genetic test that they had developed for the early detection of oral cancer. That test, called the quantitative Malignancy Index Diagnostic System, quantifies the expression levels of 14 genes associated with the FOXM1 cancer gene, and converts the measurements into a diagnostic score that indicates the risk of a lesion becoming cancerous.