Growth inhibition of head and neck carcinomas by D-allose.

BACKGROUND: An inhibitory effect of D-allose, a rare sugar, on several cancer cell lines has been reported. This study aimed to investigate the growth inhibition of head and neck squamous cell carcinoma cells by D-allose. METHODS: We treated 3 head and neck carcinoma cell lines with D-allose, D-fructose, D-psicose, and D-glucose. Cell growth assays as well as analyses of messenger RNA (mRNA) expression, cell cycle, apoptosis, and uptake of 14C-glucose were performed. RESULTS: D-allose had inhibitory effects on all 3 cell lines and tended to upregulate mRNA expression of glucose transporters, p21 and p53, and downregulate mRNA expression of cyclin A2, cyclin B1, and CDC2. We observed that D-allose tended to interfere with the intracellular uptake of D-glucose and induced apoptosis. CONCLUSION: Our results indicate that D-allose inhibits the growth of head and neck squamous cell carcinoma cells. D-allose has a considerable potential as a new anticancer agent in those patients.

Expression of prostaglandin E2 receptors in oral squamous cell carcinomas and growth inhibitory effects of an EP3 selective antagonist, ONO-AE3-240.

Prostaglandin E2 (PGE2) can stimulate tumor progression by both direct and indirect mechanisms. However, its influence on cell proliferation is still unclear. The present study characterized expression of subtypes of PGE2 receptors in oral squamous cell carcinomas, while also investigating the effects of EP3 and EP4 selective antagonists on oral carcinoma cell lines. EP1, EP2, EP3 and EP4 receptor mRNAs were detected in 4, 5, 10 and 10 of 11 surgical specimens respectively. Application of an EP3 antagonist (ONO-AE3-240) strongly inhibited cell growth in COX-2 and PGE2 high expression cells (Ca9-22) but not in COX-2 and PGE2 low expression cells (HSC4). The antagonist also reduced the production of endogenous PGE2 and induced G0/G1 phase cell arrest. Addition of exogenous PGE2 only partly abrogated the growth inhibition, indicating that the anti-proliferative effect via EP3 receptor signaling was not only due to PGE2-dependent but also PGE2-independent mechanisms. In contrast, an EP4 antagonist (ONO-AE3-208) did not inhibit growth in either of the cancer cell lines. In summary, PGE2 receptor EP3 signaling probably contributes to development of oral carcinomas and use of EP3 antagonist may be a new therapeutic strategy for head and neck cancer.

Evaluation of the therapeutic effects and recurrence for head and neck cancer after chemoradiotherapy by FDG-PET.

OBJECTIVE: The purpose of this study was to detect early stage recurrence or a residual tumor after chemoradiotherapy by FDG-PET. METHODS: A total of 51 head and neck cancer lesions in 27 patients were examined-including primary sites and metastatic lymph nodes. The therapeutic effects were evaluated by visual inspection, pre-treatment SUV, post-treatment SUV and % change in SUV. RESULTS: No local recurrence was observed in 37 of the lesions, while recurrence or a residual tumor was observed in the other 14 lesions after therapy. A significant difference was found between the two groups regarding the post-treatment SUV and the % change in SUV. Taking the post-treatment SUV of 3 and the % change of 60 as a cut-off value, a significant difference was thus found between the recurrence cases and non-recurrence cases. When all lesions were divided into two groups-including the post-treatment SUV>3 and the % change in the SUV<60 group, and the post-treatment SUV<3 or the % change in SUV>60 group, the overall accuracy was 88.2% (45/51). Therefore, it is more useful to predict the prognosis after chemoradiotherapy by a combined analysis of the post-treatment SUV and the % change in SUV. According to the post-treatment PET period, namely, within 4 weeks and from 5 to 15 weeks after treatment, the accuracy was 85.7% (24/28) and 91.3% (21/23), respectively (p=0.5385). CONCLUSION: The results suggest that it may be possible to predict the recurrence even at 4 weeks after treatment. Therefore, the use of a semi-quantitative analysis of FDG-PET between the pre-treatment and post-treatment findings is thus considered to be helpful in choosing the optimal therapy and for making an accurate prognosis.

[Study on detection of allergenic substances (egg and milk) in processed meat products and frozen foods].

Allergenic substances (egg and milk) were measured in processed meat products and frozen foods of which the milk and egg ingredient ratios and manufacturing processes were clearly identified. An ovomucoid ELISA kit gave good results in the detection of egg ingredients. With an ovalbumin ELISA kit and egg ELISA kit, results for 6 of 16 foods were negative, but better results were obtained when a protein denaturant was added to the extraction buffer. Occurrence of contamination in the egg ingredient manufacturing line was confirmed in frozen foods. For milk ingredients, good results were obtained by ELISA using two kinds of kits (a casein ELISA kit and milk ELISA kit) described as being suitable for detection of allergenic substances. Allergenic substances were identified by Western blot analysis in all of the foods containing egg and milk ingredients.