Effect of oxygenated water as a new chemopreventive modality in experimentally induced hamster buccal pouch carcinogenesis

Document Type : Original Article

Authors

1 Demonstrator, Oral and Dental Pathology Department, Faculty of Dental Medicine, (Boys- Cairo), Al-Azhar University, Egypt.

2 Assistant Professor, Pharmacology and Toxicology Department, Faculty of Pharmacy, (Boys-Cairo), Al-Azhar University, Egypt.

Abstract

The aim of the present study was directed to investigate the effect of oxygenated water as a new chemopreventive modality in experimentally induced hamster buccal pouch (HBP) carcinogenesis. Material and methods: sixty one golden Syrian male hamsters five weeks old, weighting 80-120 gs were used as experimental animals and divided into three group(s) (G(S)) (G1, G2 and G3): G1 (negative control): 5 animals were left untreated. G2: (DMBA painting-HBP group): 14 animals, their right buccal pouches were painted with 0.5% DMBA in paraffin oil 3 times a week. G3 (oxygenated water chemoprevention group): 42 animals, were subdivided according to the methods of receiving oxygen into 3 equal models each contained 14 animals: G3A which received oxygen in the free access (in water), G3B which received oxygen once daily obligatory 1 ml of the (by oral tube) in addition to the free access and G3C which received oxygen twice daily obligatory 1 ml in addition to the free access. At 6 and 14 weeks, 7 (half) animals of G2 and of each model of the G3 (G3A, G3B and G3C) were sacrificed, and the buccal mucosa was excised. Results: Gross observations revealed variable features in the treated groups (G2 and G3) compared to that observed in group G1ranging from normal and smooth surface to fungating tumor masses of large sizes. Histopathological findings revealed variations among the treated groups ranging from normal epithelial layers to epithelial dysplasia to squamous cell carcinoma with invading nests and pearls. Immunohistochemical (IHC) results, regarding Bax expression, revealed variability in the area percentage throughout the groups used. At 6 weeks, area percentages of G2, G3A, G3B and G3C were (28.58 %, 32.9 %, 37.86% and 41.27%) respectively, and at 14 weeks were (10.38 %, 14.64 %, 27.19 % and 15.59 %) respectively. Bcl2 expressions also had variability in the area percentage throughout the same groups at 6 weeks were (31.77 %, 27.36 %, 16.9 % and 8.8 %) respectively, while at 14 weeks they were (68.3 %, 54.8 %, 39.8 % and 51.74 %) respectively. Conclusion: Oxygenated water is considered as a promising chemopreventive agent in prevention of induced HBP carcinogenesis (epithelial dysplasia & invasive carcinoma) and prove beneficial role in improving the outcome by modulating apoptosis and proliferation throughout the process of carcinogenesis as visualized by Bax and Bcl2.

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