Caspase-3 expression is reduced, in the absence of cleavage, in terminally differentiated normal oral epithelium but is increased in oral squamous cell carcinomas and correlates with tumour stage.

Oral carcinomas are known to have a greater apoptotic index than normal oral epithelium, evident as shrinking cells with condensed chromatin. In this study, these morphologically apoptotic cells stained positively for cleaved (active) caspase-3. In normal oral epithelium, cleaved caspase-3 positive-cells were only rarely detected.

The cyclooxygenase 2-selective inhibitor NS398 inhibits proliferation of oral carcinoma cell lines by mechanisms dependent and independent of reduced prostaglandin E2 synthesis.

Purpose: We investigated the potential of cyclooxygenase (COX)-2 as anappropriate chemopreventive and/or therapeutic target for oral cancer.

Experimental Design: Immunohistochemical analysis of COX-2 expression was carried out on 37 oral squamous cell carcinomas (OSCCs) and 23 normal oral epithelium samples. We investigated whether the COX-2-selective inhibitor NS398 induced growth inhibition in four human OSCC cell lines and whether this was COX-2 dependent.

Deregulated Bag-1 protein expression in human oral squamous cell carcinomas and lymph node metastases.

Bag-1 is an anti-apoptotic protein that promotes metastasis in some tumour cell types. To determine whether Bag-1 expression is altered in 64 oral squamous cell carcinomas, tumour samples were compared with 17 samples of normal oral epithelium. Normal oral epithelia had pronounced nuclear staining in the basal and maturation layers and weak cytoplasmic staining that was most pronounced in the basal and suprabasal layers.