Molecular profiling of head and neck tumors

Head and neck squamous cell carcinoma is the fifth most common cancer worldwide. Unfortunately, patients with the same diagnostic and prognostic profile can have markedly different clinical outcomes. This most likely results from the fact that the current taxonomy of head and neck squamous cell carcinoma groups molecularly different diseases with distinct clinical phenotypes into classifications based mainly on morphology. A combination of circumstances, including the advent of array-based technology and progress in the human genome initiative, now provides an ideal opportunity to begin performing comprehensive molecular and genetic profiling of head and neck squamous cell carcinoma. This article reviews recently reported studies that have used such approaches.

Comparison of gene expression profiles between head and neck squamous cell carcinoma and normal tissues showed altered expression levels of genes involved in the control of cell growth and differentiation, angiogenesis, apoptosis, cell cycle, and signaling, most of which have not been previously described in head and neck squamous cell carcinoma. Additionally, they revealed the implication of different signaling and metabolic pathways such wnt and noch, highlighting the potential role of these pathways in oral cancer development. Their results provide new insights into the carcinogenesis of head and neck squamous cell carcinoma as well as a source of potential prognostic and predictive markers and targets for its prevention and therapeutics.

Although the sample sizes of these studies were small and their findings therefore require further validation in larger trials, such preliminary results provide important clues to the understanding of the various gene networks implicated in oral carcinogenesis and may contribute to the selection of target genes for possible molecular diagnosis and therapy in the future.