Study on the expression and function of smad family member 7 in oral submucous fibrosis and oral squamous cell carcinoma.

OBJECTIVE

To investigate the expression and function of smad family member 7 (SMAD7) in the progress of oral submucous fibrosis (OSF) and oral squamous cell carcinoma (OSCC).

METHODS

Mucosa tissue microarray containing 12 normal oral mucosa samples, 69 OSF samples, 28 OSCC sample and paired adjacent tissues was used to explore the expression levels in OSF and OSCC by immunochemistry. Several online bioinformatics analysis tools were used to explore "transcriptome level" and mostly probable "functions and pathways" of SMAD7 in head and neck squamous cell carcinoma.

RESULTS

SMAD7 expression was up-regulated significantly in "OSF" (P < 0.0001) and "OSCC" (P < 0.05). In the status of "OSF and OSCC with OSF", the trends of SMAD7 expression were consistent and up-regulated (P < 0.0001). Based on bioinformatics analysis results, SMAD7 was significantly higher in head and neck squamous cell carcinoma than that of normal tissues. No mutation was found in head and neck squamous cell carcinoma. Pathway analysis results showed three mostly probable functions (extracellular matrix organization, blood vessel development and laminin interactions) and two mostly probable pathways (regulation of actin cytoskeleton and ras-associated protein-1 signaling pathway) that SMAD7 participated in.

CONCLUSIONS

In OSF and OSCC, SMAD7 is indicated to be a promoter, as well as a potential diagnostic biomarker.