Hirohiko Tachibana

Circulating miR-223 in Oral Cancer: Its Potential as a Novel Diagnostic Biomarker and Therapeutic Target.

Circulating microRNAs (miRNAs) have been detected in various types of cancer and have been proposed as novel biomarkers for diagnosis and treatment. Until recently, however, no studies had comprehensively examined circulating miRNAs in oral cancer. The current study used an ultra-sensitive genome-wide miRNA array to investigate changes in circulating miRNAs in plasma from five patients with oral cancer and ten healthy individuals. Results indicated that there were only a few circulating miRNAs, including miR-223, miR-26a, miR-126, and miR-21, that were up-regulated in patients with oral cancer. A subsequent validation test indicated that circulating miR-223 levels were significantly higher (~2-fold, P< 0.05) in patients with oral cancer (n = 31) than in those without cancer (n = 31). Moreover, miR-223 was found to be up-regulated in tumor-adjacent normal tissue compared to tumor tissue from patients with oral cancer. A gain-of-function assay was performed to explore the potential roles of circulating miR-223 in the development of oral cancer. Results revealed that miR-223 functions as a tumor suppressor by inhibiting cell proliferation and inducing apoptosis. In conclusion, this study suggested that circulating miR-223 may serve as a potential biomarker for diagnosis and that it may represent a novel therapeutic target for treatment of oral cancer.

Significant improvement in temporary dental rehabilitation by notable miniplate application in the hard palate for a patient with a large anterior maxillary defect: a case report/technique article.

The present report describes the application of a miniplate in the hard palate of a 36-year-old patient with a large anterior maxillary defect. The combination of orthodontic elastics with a titanium miniplate improved the stability of the prefabricated prosthesis. This structure retained the ointment gauze covering the wounds and maintained the facial contour. In addition, contracture deformity was prevented by insertion of the prefabricated prosthesis intraoperatively or immediately postoperatively. Furthermore, a soft diet could be ingested immediately postoperatively. The miniplate also supported the anterior part and the definitive prosthesis. This prosthesis restored adequate masticatory, deglutitive, and speech functions and maintained the facial contour with minimum overloading of the remaining teeth.

Disseminated Intravascular Coagulation after Surgery for Facial Injury

A case of disseminated intravascular coagulation (DIC) presenting after surgery for facial trauma associated with multiple facial bone fractures is described. With regard to the oral and maxillofacial region, DIC has been described in the literature following head trauma, infection, and metastatic disease. Until now, only 5 reports have described DIC after surgery for facial injury. DIC secondary to facial injury is thus rare. The patient in this case was young and had no medical history. Preoperative hemorrhage or postoperative septicemia may thus induce DIC.

A Case of Simultaneous Unilateral Anterior and Posterior Stafne Bone Defects

Stafne bone defects (SBDs) are asymptomatic mandibular lingual bone depressions mainly caused by soft tissue inclusions. The most common form of SBDs is posterior; the anterior variant of SBD is relatively uncommon. Although posterior SBD is easily diagnosed by the unique location on radiography, anterior SBD is sometimes misdiagnosed and confused with other pathological entities owing to the location. We report herein a case of simultaneous unilateral anterior and posterior SBDs. In the present case, definitive diagnosis for the anterior mandibular cavity was unclear, as in reported cases. Surgical exploration was thus performed for the lesion in the anterior mandibular cavity. Pathologic examination of the removed tissue showed salivary gland with chronic inflammation. Postoperatively, no functional disturbance has been observed. Management of the posterior SBD was conservative, with radiographic follow-up. To the best of our knowledge, this represents the first report of simultaneous unilateral anterior and posterior SBDs.

Myoepithelioma of the upper lip

Myoepithelioma is a rare form of salivary gland tumor composed entirely of myoepithelial cells. This tumor was formerly considered to be a subtype of pleomorphic adenoma; however, in the 1991 World Health Organization classification, it is listed as an independent entity. The most favorable site of occurrence of myoepithelioma is the parotid gland. Here, we report an extremely rare case of myoepithelioma of the upper lip. A 56-year-old woman presented with a painless mass on her upper lip. Magnetic resonance imaging revealed a 23 mm × 18 mm well-defined ovoid tumor. A benign minor salivary gland tumor was clinically suspected, and the patient underwent complete resection of the tumor under general anesthesia. The tumor was histopathologically diagnosed as a benign myoepithelioma of the minor salivary gland. Immunohistochemically, the tumor cells were positive for S-100 protein, AE1/AE3, CAM5.2, CK7, vimentin, and calponin, confirming the morphologic diagnosis of myoepithelioma. The patients postoperative clinical course was uneventful, and satisfactory results were obtained both functionally and esthetically. To the best of our knowledge, this is the sixth case of myoepithelioma of the upper lip reported in English-language research.