Makoto Toida

Effects of green tea polyphenol on methylation status of RECK gene and cancer cell invasion in oral squamous cell carcinoma cells.

RECK is a novel tumour suppressor gene that negatively regulates matrix metalloproteinases (MMPs) and inhibits tumour invasion, angiogenesis and metastasis. In the present study, we investigated the effects of epigallocatechin-3-gallate (EGCG), a major polyphenol in green tea, on the methylation status of the RECK gene and cancer invasion in oral squamous cell carcinoma cell lines. Our results showed that treatment of oral cancer cells with EGCG partially reversed the hypermethylation status of the RECK gene and significantly enhanced the expression level of RECK mRNA. Inhibition of MMP-2 and MMP-9 levels was also observed in these cells after treatment with EGCG. Interestingly, EGCG significantly suppressed cancer cell-invasive ability by decreasing the number of invasive foci (P<0.0001) as well as invasion depth (P<0.005) in three-dimensional collagen invasion model. Although further investigation is required to assess the extent of contribution of RECK on MMPs to the suppression of invasive behaviour, these results support the conclusion that EGCG plays a key role in suppressing cell invasion through multiple mechanisms, possibly by demethylation effect on MMP inhibitors such as RECK.

Adenomatoid odontogenic tumor: Report of two cases and survey of 126 cases in Japan

The object of this report is to present two new cases of AOT, to elucidate the clinical features of this tumor in Japan, and to briefly compare the latter findings with those reported in the world literature

Matrix metalloproteinases 2 and 9 in oral squamous cell carcinomas: manifestation and localization of their activity

PurposeThe process of invasion and metastasis is closely related to the prognosis of oral squamous cell carcinoma (OSCC). Matrix metalloproteinases (MMPs) are a group of enzymes characterized by their ability to degrade extracellular matrix proteins and contribute to the tumor invasion and metastasis. Especially MMP-2 and MMP-9 are known to be related to destruction of basement membrane as collagenases. This study focused on protein expression of MMP-2 and MMP-9 and their extracellular matrix degradation activity in OSCCs.MethodsFreshly frozen samples from 31 OSCC patients were analyzed for the localization and activity of MMP-2 and MMP-9. Serial frozen sections were used by routine hematoxylin and eosin staining, immunohistochemistry for MMP-2 and MMP-9, and film in situ zymography (FIZ) for gelatinolytic activity. We also evaluated the activity of MMP-2 and MMP-9 by zymography using the same samples as frozen sections. The activated form/proform ratio of MMPs in zymography was evaluated using an image scanner.ResultsIn MMP-2 the proportion in T3 and T4 clinical stage groups was significantly higher than that in T1 and T2. The proportion in lymph node metastasis cases (N+) was also significantly higher than that in non-lymph node metastasis cases (N−). In contrast to MMP-2, the activated form/proform ratio of MMP-9 was very low, suggesting that MMP-9 is not activated in the matrix degradation of OSCC, although both MMP-2 and MMP-9 protein expression are presented in tumor cells. FIZ revealed MMP in both tumor cells and stromal cells of 70% of the N+ cases and of 47.6% of the N− cases.ConclusionsThese results indicate that two types of proform and activated form matrix metalloproteinases, MMP-2 and MMP-9, are present in human OSCC, and that the activated MMP-2 could be a main enzymatic activity of gelatinolysis in OSCC. Interaction of tumor cells and stromal cells seems to play an important role in the invasion and metastasis of human OSCC. Combination analysis of zymography and FIZ is a usuful method to detect activity and localization of MMPs in human OSCC.

Lobular capillary hemangioma of the oral mucosa: clinicopathological study of 43 cases with a special reference to immunohistochemical characterization of the vascular elements.

Clinical and histopathological features were investigated in 43 cases of oral lobular capillary hemangiomas (LCH) with a special reference to characteristics of the vascular elements. The lesions affected females more than males by a ratio of 1:1.5. Average age of the patients was 52.7 years. The lesions involved the gingiva (n = 15), the tongue (n = 13), the labial mucosa (n = 10) and other sites. The lesions appeared usually as a pedunculated mass with ulceration; size of the lesions was up to 15 mm. Histologically, a lobular area and an ulcerative area were distinguished. The density of vessels was about 1045/mm2 and 160/mm2 in the lobular and ulcerative areas, respectively. The average diameter of the vascular lumen was 9.1   5.6 mm (range: 2.8–42.0 mm) and 18.8  20.9 mm (range: 5.6–139.7 mm) in the lobular and ulcerative areas, respectively. In the lobular area, most of the vessels had an inner layer of endothelial cells showing positive reaction for von Willebrand factor (vWF) and CD34, as well as an outer layer of mesenchymal cells showing positive reaction for alpha‐smooth muscle actin (ASMA). However, in the ulcerative area, there was a variety of types of vessels consisting of various proportions of both endothelial and ASMA‐positive perivascular mesenchymal cells. These results indicate that most of the vascular elements in the lobular area resemble more pericapillary microvascular segments than they do capillaries. Thus, the authors propose the term ‘lobular pericapillary hemangioma’ to represent this type of lesion.

A simple cryosurgical method for treatment of oral mucous cysts

A simple and easy cryosurgical method to treat intraoral mucous cysts is described. Twelve female and six male patients, with mucous cysts on the lower lip and the tip of the tongue, were treated by direct application of liquid nitrogen with a cotton swab. Each lesion was exposed to four or five cycles composed of freezings of 10-30 s and thawings of double the freezing times. No anesthesia was required. All lesions had disappeared completely 2-4 weeks after one or two treatment courses of cryosurgery. In all cases, neither scarring nor recurrence was noted during the 6 months to 5 years of follow-up.

Hypermethylation of the RECK gene predicts poor prognosis in oral squamous cell carcinomas

The RECK gene is a novel tumor suppressor gene that regulates matrix metalloproteinases (MMPs) to inhibit tumor angiogenesis, invasion and metastasis. We investigated the methylation status of the RECK gene in 40 primary oral squamous cell carcinomas (OSCC) and 20 paired adjacent normal mucosa by methylation-specific PCR. Furthermore, we determined the prognostic importance of RECK hypermethylation in OSCC patients. Our findings showed that the RECK gene was methylated in 52.5% (21 of 40) of the primary OSCC. Among the 20 cases with corresponding normal tissues, RECK hypermethylation was detected in both primary tumor (55%, 11 of 20) and adjacent normal mucosa (30%, 6 of 20). Methylation of the RECK gene was not detected in all normal oral mucosa samples of the 12 healthy controls. In univariate analysis, RECK hypermethylation was inversely correlated with recurrence-free survival (p=0.027) and overall survival (p=0.023) of the OSCC patients. Multivariate analysis showed that the methylation status of the RECK gene was the only independent prognostic factor affecting overall survival (p=0.037). The result indicates that hypermethylation of RECK promoter is a common event in human OSCC, occurs concurrently in tumor-adjacent normal mucosa and is correlated with poor prognosis in OSCC patients. Although additional work is needed, hypermethylation of the RECK gene is a promising biomarker in early detection and prognosis for oral cancer patients.

Glandular odontogenic cyst: a case report and literature review.

In 1992, the World Health Organization (WHO) named glandular odontogenic cyst (GOC) as an independent pathologic entity and classified it as a developmental odontogenic epithelial cyst.1,2 The WHO defined this lesion as “a cyst arising in the tooth-bearing areas of the jaws and characterized by an epithelial lining with cuboidal or columnar cells both at the surface and lining crypts or cyst-like spaces within the thickness of the epithelium.”1 GOCs occur over a wide age range in both sexes and in either jaw, and have the propensity to recur and to become large. Radiographically, the GOC appears as an intrabony, unilocular or multilocular, sometimes honeycomblike, well-defined radiolucent lesion. Histologically, the lining epithelium may be partly squamous, without distinctive features.1 However, in many areas, the stratified epithelium has a surface layer of eosinophilic cuboidal or columnar cells, often forming irregular papillary projections.1 A variable number of ciliated and mucus-producing cells may also be interspersed in the surface layer.1 Within the thickness of the epithelium there may be crypts and glandular or cystlike spaces lined by cells similar to those seen in the epithelial surface.1 Pools of mucous material within the intraepithelial spaces and within the main cyst cavity are a prominent feature. Plaquelike and whirlpoollike epithelial thickenings also may be present.1 The fibrous capsule is usually free of inflammatory cells.1 Multicystic or botryoid varieties also occur.1 Because this lesion has been characterized only recently, and only a few cases have been reported in the literature,3–8 its biologic nature is uncertain.1,2 However, the aggressive behavior and the recurrent tendencies of this lesion have been suggested,1,2 even in the limited number of reported cases.3–8 We report a case of GOC that exhibited histologic features suggesting the aggressive and somewhat neoplastic nature of this lesion. Furthermore, the clinicopathologic features of 17 cases reported in the literature3–8 are reviewed, and the differential diagnosis of this rare lesion, especially from central low-grade mucoepidermoid carcinoma (MEC), as well as its treatment, are also discussed.

Usefulness of Low-Level Laser for Control of Painful Stomatitis in Patients with Hand-Foot-and-Mouth Disease

OBJECTIVE The aim of this study was to evaluate the usefulness of low-level laser therapy (LLLT) for the control of painful stomatitis in patients with hand-foot-and-mouth disease (HFMD). BACKGROUND DATA LLLT has been successfully applied to various painful oral mucosal diseases, although there have been few reports on LLLT for HFMD patients. MATERIALS AND METHODS Through a randomized double-blind placebo controlled trial, the painful period of HFMD stomatitis was compared between the LLLT group (n=11) and the placebo LLLT one (n=9), which had similar clinical backgrounds. The LLLT parameters supplied were as follows: wavelength of 830 nm, power of 30 mW, frequency of 30 Hz, and energy output of 1.1 J/cm2. Acceptability and safety of the treatment were also evaluated. RESULTS The painful period was shorter in the LLLT group (4.0 +/- 1.3 days) than in the placebo LLLT one (6.7 +/- 1.6 days) with a statistically significant difference (p<0.005). The treatment was judged acceptable for 90.0% (18 of 20) of patients. No adverse events were observed in any cases. CONCLUSION LLLT is a useful method to control HFMD stomatitis by shortening the painful period, with its high acceptability and lack of adverse events.

Analysis of genetic alterations in salivary gland tumors by comparative genomic hybridization

In order to define and map chromosomal copy number alterations in salivary gland tumors (SGTs), a comparative genomic hybridization (CGH) technique was applied to two pleomorphic adenomas (PAs), one adenoid cystic carcinoma (ACC), and one basal cell adenocarcinoma (BCAC). The PAs exhibited regional copy number losses at 5q12.4-q14.1, 9q12-q21.13, and 16q11.2, as well as a gain at 20p12.1; among these, the losses at the 9q12-q21.11 and 16q11.2 regions were common to both PAs. The ACC showed overrepresentations of the entire regions of chromosomes 16 and 20, a regional gain at 22q12.3-q13.1, and no losses. In the BCAC, regional gains at 9p21.1-pter, 18q21.1-q22.3, and 22q11.23-q13.31 as well as losses at 2q24.2 and 4q25-q27 were seen; the gain at 22q12.3-q13.1 was common in both the ACC and the BCAC. These CGH data indicate that different genetic alterations are present in the different types of SGTs, and that the alterations involve several chromosomes. The discovery of common alterations in the same and/or different types of tumors might be important in the understanding of the development and progression of the SGTs.

Kabuki make-up syndrome (Niikawa-Kuroki syndrome) with cleft lip and palate

Kabuki make-up syndrome (Niikawa-Kuroki syndrome), recognized in Japan in 1981, is characterized by mental and growth retardation with specific craniofacial malformation such as lower palpebral eversion and depressed nasal tip. In this paper we describe a case associated with cleft lip and palate. Attention should be paid by maxillofacial surgeons to this syndrome, since 41% of the cases have been associated with cleft lip and palate (Niikawa et al., 1988; Tonoki and Niikawa, 1988).