Molecular profiling of oral squamous cell carcinoma associated with oral submucous fibrosis

Areca nut, a causative factor for oral submucous fibrosis (OSMF), is identified as a Group 1 human carcinogen. Oral squamous cell carcinoma (OSCC) associated with OSMF is now one of the most common malignancies in South and Southeast Asian countries.

The present study was aimed to have clarity whether OSCC associated with OSMF is a pathologically different disease having different prognosis.

The difference between OSCC associated with OSMF and OSCC not associated with OSMF was studied in relation to expression of molecular markers, Ki-67, a proliferative and prognostic marker for OSCC and matrixmetalloproteinase-9 (MMP-9), and alpha smooth muscle actin (α-SMA), markers for invasiveness.

Expression was analyzed immunohistochemically using paraffin-embedded tissues from ten normal oral mucosa (Group I), thirty OSCC associated with OSMF (Group II), and thirty OSCC not associated with OSMF (Group III).

Group II showed OSCC occurring at younger age with more cases of well-differentiated OSCC. It also showed lower expression of Ki-67, MMP-9, and α-SMA as compared to Group III, and the difference was statistically significant. In addition, statistically significant low expression of markers was found in well and moderate grades of Group II as compared to those of Group III.

OSCC associated with OSMF may have better prognosis and survival rate as it is found to occur at younger age with better grade of tumor differentiation and less expression of molecular markers Ki-67, MMP-9 and α-SMA. Thus, OSCC associated with OSMF can be considered a different disease pathologically and biologically. In-depth analysis of this molecular profiling can help to establish diagnostic, prognostic and therapeutic modalities for this unique malignancy.