This comparative analysis was done to assess cancer data on Filipinos in the Philippines and migrant Filipinos, to review the trends of cancer incidence with emphasis on oral cancer on both populations and to recommend needs based on findings. The current data on oral cancer in the Philippines revealed varying results on the reported incidences within the country. The country is evolving as a new oral cancer hotspot in Southeast Asia. A general trend of increase in oral cancer and general cancer incidence rates among migrant Filipinos for both sexes was seen when compared with home country values. The urgent need for additional epidemiological and experimental data and research on other regional areas of the country as well as other top destinations for Filipino migrants was seen to fully supplement the current available cancer data.

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Decalcified bone implants induce new bone formation. In this experiment, the autogenous bone implant of canine mandible was treated by HCl under ultrasonic exposure for rapid decalcification. The aim of this study was to investigate the osteoinduction property of this rapidly decalcified bone reimplanted to the original site. The decalcified bone implant exhibited a similar degree of new formation to that of the fresh bone graft which was not subjected to decalcification. The results demonstrate that the combinational use of HCl and ultrasonic exposure for rapid decalcification treatment preserves the regenerative capacity of bone to be implanted.

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Induction of mucosal immunity by direct immunization of mucosal surfaces has been considered for vaccine approaches including DNA vaccines. In this study, we used a particle-mediated gene gun system in hamster, rabbit, and canine models to determine suitable conditions for foreign gene delivery to the oral mucosa. The results showed expression of the marker genes (green fluorescent protein gene and luciferase gene) in the oral mucosa that was substantially higher compared with skin. DNA vaccination was performed with influenza A/WSN/33(H1N1) hemagglutinin cDNA combined with mouse interleukin-18 (IL-18) cDNA. Results with the canine model showed that the technique was safe for clinical application. Our results suggested that oral mucosal gene immunization using a gene gun may have great potential.

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E1AF, an ets-oncogene family transcription factor, has been shown to upregulate transcription from matrix metalloproteinase (MMP) genes, which confers the invasive phenotype on cancer cells. On the other hand, we have demonstrated by luciferase assay that E1AF positively regulates transcription from the p21^waf1/cip1 promoter. Ca9.22 cells were transfected with a metallothionein-inducible E1AF expression vector (Ca9.22MTF) to investigate the relationship between invasive ability and cell cycle modulation caused by E1AF. MMP-9 and p21^waf1/cip1 protein were synergistically increased in the ZnCl₂ stimulated CA9.22MTF cells, and both proteins were identified in the same cells when E1AF was induced. These results imply that invasive growth of tumor cells occurs in the static state of the cell cycle and that E1AF plays a key role in this phenomenon.

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The melanoma is a malignant neoplasm of melanocytic origin, and four clinicopathologic types are recognized: lentigo maligna melanoma, superficial spreading melanoma, nodular melanoma and acral lentiginous melanoma (ALM). The latter differs from ordinary malignant melanoma in exhibiting a predominant radial growth phase. ALM of the oral mucosa is rare. Although the prognosis of such lesions is reportedly poor, some studies show encouraging results with early diagnosis and adequate treatment. The present case highlights the potential role of a dental surgeon in early detection and recognition of signs of malignancy in melanotic lesions. A loose denture may be the only complaint of such a lesion. The need for biopsy at multiple sites to ensure accurate diagnosis is also highlighted. The management of oral ALM is discussed.

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Adenomatoid odontogenic tumors are uncommon odontogenic lesions of which biological features have not been fully understood. We report a case of adenomatoid odontogenic tumor arising in a pregnant woman. The patient was a 20-year-old Japanese female complained of a swelling in the right maxillary gingiva and the swelling rapidly enlarged in size after pregnancy. We investigated the lesion immunohistochemically to find out biological behavior. Bcl-2 protein was strongly positive, and growth activity determined by MIB-1 was extremely high. Immunoreactivity for estrogen receptor was not detected. These results suggest that this adenomatoid odontogenic tumor showed rapid growth due to high proliferative activity and also inhibition of apoptotic cell loss but not dependent on estrogen receptor in our case.

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A 30-year-old Japanese man presented white spongy plaques on his buccal mucosa and lower lip. The surface of the lesion showed irregular and small portions of the plaques were desquamative. Histopathologically, stratified squamous epithelium characterized by acanthosis and parakeratosis of surface layer was identified. Marked intracellular edema without spongiosis and vacuolated spinous cells were observed. Topical steroid and laser treatment were not effective, but the lesion disappeared completely after treatment with azithromycin.

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