Detection of TGIF1 homeobox gene in oral squamous cell carcinoma according to histologic grading.

Objective: TGIF1 homeobox gene involvement in oral cancer has not yet been investigated. This study analyzed the expression of TGIF1 transcripts and protein in oral squamous cell carcinoma (OSCC).

Study Design: Snap-frozen samples from 16 patients were taken from both OSCC and nontumoral adjacent epithelium (NT) for in situ hybridization (ISH). Forty-six paraffin-embedded samples of OSCC were submitted to immunohistochemistry (IHC). A descriptive analysis of the transcript signal detection was accomplished, and TGIF1 immunoexpression was carried out considering protein levels, localization, and cellular differentiation.

Results: ISH reactions showed TGIF1 transcripts with a signal that was frequently intense in NT, and generally weak in OSCC, and that had stronger transcript signal in well-differentiated areas of OSCC when compared with poorly differentiated ones. IHC reactions had poorly differentiated cases associated with TGIF1 protein expression in both the nucleus and cytoplasm (P = .05, Fisher test).

Conclusions: TGIF1 gain or loss of function might possibly play a role in oral cancer cell differentiation.