Gene expression profiling in head and neck squamous cell carcinoma: Clinical perspectives

Abstract

Some transcriptional signatures that could improve HNSCC management have been identified, but further analyses are required to properly validate and to precisely evaluate their clinical relevance. After an exploratory phase, the completion of large scale projects with stringent methodology is now necessary to transfer GEP from bench to bedside.

Molecular Genetics and Biology of Head and Neck Squamous Cell Carcinoma: Implications for Diagnosis, Prognosis and Treatment

“…Gene expression signatures constitute an additional biological approach used to: identify screening and diagnostic molecular markers, improve tumour staging (cervical lymph node and distant metastasis prediction), differentiate lung metastasis of HNSCC from primary lung squamous cell carcinomas, predict tumour response to therapy, and provide outcome predictors (Lallemant et al, 2010). Two technologies are currently used: DNA microarrays, which extensively measures the expression of thousands of genes, and qRT-PCR, which provides a more accurate quantification of the expression of more limited number of transcripts.…”

“…It is possible to use matched or unmatched normal tissue samples as a control, in which matched tissue is taken from the same patient from whom the tumour sample was obtained, while unmatched sample is obtained from subjects without cancer. However, from the pooled gene expression data, it was possible to identify a group of genes reported by multiple studies to be significantly up-regulated and down-regulated in HNSCC (Choi & Chen, 2005;Lallemant et al, 2010). These genes were used to encode cytoskeletal and extracellular matrix proteins, inflammatory mediators, proteins involved in epidermal differentiation and cell adhesion molecules (Choi & Chen, 2005).…”

“…Differences between metastatic and non-metastatic tumours may be detected. Data from fourteen studies demonstrated that specific differences in gene expression exist between N+ and N0 HNSCC (Lallemant et al, 2010).This difference can be used to predict the N status on initial diagnostic biopsy. On the contrary, a few studies have tried to find gene expression signatures that could predict the development of distant metastasis in HNSCC, but to date, poor results have been obtained (Choi & Chen, 2005).…”

“…One of the main difficulties during the diagnosis of HNSCC is detecting microscopic tumour clusters, known to be easily overlooked by conventional histopathological methods in lymph nodes and/or surgical margins (Lallemant et al, 2010). Micrometastases are responsible for cancer recurrence in the neck o f p a t i e n t s c l a s s i f i e d a s N 0 a n d , w h o consequently did not receive a prophylactic treatment either by neck dissection or radiotherapy.…”

“…As suggested by preliminary results, gene expression signatures may greatly facilitate the identification of micrometastases in N0 patients. In the same way, the development of high frequency recurrence may be due to the presence of microscopic cancer cells cluster in the resection margins disregarded by conventional microscopy (Lallemant et al, 2010). Among the molecular markers with proven predictive value for lymphatic disease are E-cadherin, podoplanin, p16, bmi-1 and LOX Lallemant et al, 2010).…”