Invadopodia are membrane protrusions into the extracellular matrix by aggressive tumor cells. Through reorganization of the actin cytoskeleton, these structures are associated with sites of matrix degradation and invasiveness of malignant tumor cells in an in vitro fibronectin degradation/invasion assay. In this study, we examined cell morphology and invasive activity for three cell lines derived from human oral squamous cell carcinomas with different invasive modes. According to Yamamoto-Kohama's classification, OSC-20 was classified as grade 3, OSC-19 as grade 4C, and HOC313 as grade 4D. OSC-20 and OSC-19 showed pavement stone patterns, and HOC313 showed a fibroblast-like cell pattern. OSC-19 and HOC313 showed dot-like degradation in the in vitro fibronectin degradation/invasion assay, whereas OSC-20 showed diffuse-type degradation. Our results suggest that reorganization of the actin cytoskeleton and cell shape are related to the invasiveness of oral squamous carcinoma cells.
Neural cell adhesion molecule (NCAM) is one cell surface glycoprotein and a member of the immunoglobulin superfamily. It has been reported that NCAM may be associated with perineural invasion by malignant glandular tumors, such as bile duct carcinoma or gallbladder carcinoma. However, it remains unclear whether NCAM is really associated with the development of salivary gland tumors. Previous studies have demonstrated that NCAM is constitutively expressed in the human salivary gland tumor cell line HSG in vitro. In this study, molecular mechanisms of perineural invasion were examined using HSG cells in which NCAM-mediated inhibition of salivary gland tumor proliferation is caused by homophilic binding. In addition, the localization of NCAM in adenoid cystic carcinomas (ACCs) was examined immunohistochemically. The levels of NCAM mRNA and protein expression were found to decrease in a dose-dependent manner on treatment with anti-NCAM antibody. The MTT assay revealed a significant reduction in the number of viable HSG cells. Confocal laser microscopy showed that HSG cells undergo apoptosis in response to treatment with anti-NCAM antibody. The activation of caspases 3, 7, and 9 was observed in HSG cells after treatment with anti-NCAM antibody, thus confirming the induction of activated caspase-mediated apoptosis. The up-regulation of TGF-β1-mediated NCAM expression seemed to lead to the activation of homophilic NCAM binding, further accelerating HSG cell proliferation. Immunohistochemical examinations revealed that NCAM was slightly to moderately positive in 9 of 13 cases (69.2%) of ACC. These findings suggest that NCAM is associated not only with a cell-to-cell adhesion mechanism but also with tumorigenesis, including growth, development, and perineural invasion in human ACCs.
Metastasis in invasive carcinoma is closely associated with the production of extracellular matrix catabolic enzymes such as matrix metalloproteinases (MMPs), as well as with enhanced cell motility and growth. It is known that ets oncogenes exist in transcriptional regulation regions of MMPs, such as AP1 sites, and enhance or inhibit MMP transcription. In this study, we investigated the effect of ets-1, a member of the ets oncogene family, on the invasive properties of oral cancer from a molecular biological perspective. By means of lipofection, an oral squamous carcinoma cell line was transfected with ets-1. The invasive ability of the transfected cells was determined using a matrigel invasion assay, and MMP-9 production was measured using gelatin zymography. The results for the transfected cells were compared with those for normal cultured cells. Matrigel invasion assay revealed that the transfected cells had higher invasive ability than that of normal cultured cells, and gelatin zymography demonstrated that their MMP-9 production had increased. These results suggest that ets-1 is involved in enhanced invasive ability and increased MMP-9 production in oral squamous carcinoma cells.
We report a case of congenital insensitivity to pain with anhidrosis (CIPA), a intractable ulcer of the oral mucosa, and fever of unknown origin. A 4-month-old girl was referred to our clinic on May, 1999 because of an ulcer of the lower gingiva and the oral floor, accompanied by a high fever. The present episode of ulcer and high fever began 1 month before presentation. The patient was malnourished as an infant, and physical findings were essentially normal. There was an ulcer, measuring 3×3cm on the lower gingiva and the oral floor. We treated the ulcerative lesion, and she was admitted to the Department of pediatrics to improve physical status. Clinical examination did not reveal the cause. CT and MRI scans of the head showed no abnormal findings. While we were perplexed about the diagnosis, CIPA was suggested when the patient showed painless behavior at venipuncture, biting her finger. CIPA was diagnosed by the sweating test, biopsy of nerve and skin, and mutations in the TRKA/NGF receptor gene. The ulcer of the gingiva and oral floor rapidly improved in response to exercise restraint of an arm. Afterward, ulcers of inferior lingual surface and buccal mucosa appeared with teeth eruption, but the ulcers improved after milling the teeth.
We report a case of florid cemento-osseous dysplasia (FCOD) occurring in the mandibular ramus. The patient was a 21-year-old woman who had had discomfort in the right mandibular gingiva. Since a panoramic radiograph by her dental practitioner showed a radiopacity in the right side of the mandible, she was referred to our department. A radiographic examination revealed a massive radiopaque lesion, measuring approximately 3×3cm, involving the entire mandibular ramus. The lesion was removed under general anesthesia. The lesion was diagnosed as a FCOD or other cemento-osseous dysplasia. There was no evidence of recurrence 18 months after the operation.
we evaluated the analgesic efficacy of fentanyl patches for terminal stage patients with oral cancer. In all cases (two cases of tongue cancer, one of gingival cancer, and one of soft palate cancer), we could assess effectiveness. We consider fentanyl patches to be a useful analgesic with high and continued effectiveness against pain in terminal stage patients with oral cancer.
Myofibroma is a rare benign localized or generalized proliferation of fibroblastic tissue occurring exclusively in infants or children. In the oral region, most lesions occur in the mandible, lip, buccal mucosa, and tongue, but and lesions arising in the maxilla are very rare. Myofibroma has an aggressive clinical presentation and is often over- treated because of an inappropriate diagnosis. We report a case of myofibroma arising in the left side of the maxilla of a 9-year-old girl and describe the differential diagnosis from other spindle cell lesions. Surgical resection of the tumor was performed under general anesthesia. Immunohistochemical staining was very useful for establishing the diagnosis, since histopathological diagnosis with conventional staining could not distinguish myofibroma from spindle cell tumors, especially fibrosarcoma. Fibrosarcoma is positive for vimentin and negative for anti-muscle-specific actin antibody (HHF-35), but this tumor was positive for both vimentin and HHF-35. These features led to the diagnosis of myofibroma. The patient has shown no signs of recurrence during 2 years of follow-up.
Methemoglobinemia is characterized by increased quantities of methemoglobin. Methemoglobin is useless as an oxygen carrier and thus causes a varying degree of cyanosis. An 18-day-old girl weighing 3.2kg was referred to our department because of congenital teeth (upper and lower). The teeth were extracted under general anesthesia. To reduce bleeding, the surgeon injected 0.8m1 of 3% propitocaine with felypressin at the surgical site. After approximately 1.5hrs, the neonate became pale and cyanotic. Arterial blood gas analysis revealed a methemoglobin plasma concentration of 43.9%. Methylene blue was given at a total dose of 5mg, and the methemoglobin level improved to 2%. The subsequent course of the neonate was uneventful, and she was discharged in a satisfactory condition.
Ameloblastoma often tends to infiltrate or recur, although it is a benign tumor with slowly expansive growth. Based on these features, extensive surgical resection similar to that for malignant tumors is considered the treatment of choice. However, such treatment sometimes results in functional and aesthetic disorders. This article describes three female patients with mandibular ameloblastoma who underwent marginal resection and mandibular reconstruction with bone grafts by an intraoral approach. The mandibular defect was repaired with an iliac bone graft combined with particulate cancellous bone and marrow in two patients, and with chin bone in one patient. About 7 months after the operation, endosseous implants were placed. After confirming osseointegration (about 6.5 months later), abutments were placed, and prosthetic reconstruction was carried out. In all patients, masticatory function was well restored by dental implants in the grafted bone, and good aesthetic results were achieved. We believe that intraoral resection and reconstruction with a bone graft followed by application of dental implants is one of the treatments of choice for mandibular ameloblastoma.
Many reports describe how a foreign body was accidentally inserted into oral soft tissue during dental treatment. Sometimes it is very difficult to locate inserted foreign bodies, without damaging adjacent tissues. This report describes the use of a metal detector to locate metallic foreign bodies, such as an inlay, file, and knifepoint fragments, lodged in the oral or maxillary region (or both). The metallic detector (Implant Finder®, Degussa AG, Germany) is routinely used to look for fixtures under the gingival mucosa at secondary implant operations. Detection of materials was possible within a 10mm depth in principle, of objects such as dental metal, bars, and suture needles. Use of an Implant Finder® facilitated removal of foreign bodies, thus helping to avoid unnecessary incisions and dissection of other parts. Postoperative recovery was excellent, without nerve damage or recurrence of inflammation.