Bone Regeneration Using Rat-Derived Dedifferentiated Fat Cells Combined with Activated Platelet-Rich Plasma.

Bone regeneration using mesenchymal stem cells has several limitations. We investigated adipose-derived dedifferentiated fat (DFAT) cells as an alternative, and evaluated their cell proliferation rate, osteoblast differentiation, and bone regeneration ability in combination with activated platelet-rich plasma (aPRP). Rat DFATs and aPRP were isolated using ceiling culture and centrifugation, respectively. The cell proliferation rate was measured, and the cells were cultured in an osteoblast differentiation medium under varying concentrations of aPRP for 21 days and stained with Alizarin red. Gene expression was evaluated using real time polymerase chain reaction. Critical defects were implanted with DFAT seeded gelatin sponges under aPRP, and four weeks later, the bone regeneration ability was evaluated using micro-computed tomography and hematoxylin-eosin staining. The cell proliferation rate was significantly increased by the addition of aPRP. Alizarin red staining was positive 21 days after the start of induction, with significantly higher Runt-related transcription factor 2 (Runx2) and osteocalcin (OCN) expression levels than those in the controls. A 9 mm critical defect was largely closed (60.6%) after four weeks of gelatin sponge implantation with DFAT and aPRP. Therefore, materials combining DFAT cells and aPRP may be an effective approach for bone regeneration. Further research is needed to explore the long-term effects of these materials.

Malignant mesothelioma metastatic to the oral region and latest topics (Review).

Malignant mesothelioma (MM) is a rare neoplasm with poor prognosis that usually develops after exposure to asbestos, and is characterised by aggressive local invasion and metastatic spread. While metastasis to the oral cavity is very rare, a total of 23 cases of MM metastasising to the oral cavity were identifed. Among those, the tongue was the most common site of metastasis (39.1%), and frequently involved the epithelioid MM cell type. Recent studies have elucidated the mechanisms underlying the development of MM. Chronic inflammation has been implicated in promoting MM growth and was shown to play a key role by driving the release of high mobility group box protein 1 following asbestos deposition. Inherited heterozygous germline mutations in the deubiquitylase BRCA-associated protein 1 were shown to increase the incidence of MM in some families. Infection by the simian virus 40 was also found to be associated with the occurrence of MM. Moreover, the increasing incidence rates of MM, together with its propensity to metastasise to the oral cavity, indicate that clinicians and pathologists should be highly aware of this disease. Furthermore, identification of novel serum biomarkers would enable better screening and treatment of MM, and improve the survival outcomes.

Curcumin inhibits epithelial-mesenchymal transition in oral cancer cells via c-Met blockade.

Oral squamous cell carcinoma (OSCC) is the most common type of oral cancer. OSCC cells are highly invasive, a characteristic that involves epithelial-mesenchymal transition (EMT); the conversion of immotile epithelial cells into motile mesenchymal cells. EMT is involved in the progression of various types of cancer by promoting tumour cell scattering and conferring to these cells cancer stem cell (CSC)-like characteristics, such as self-renewal. Hepatocyte growth factor (HGF) signalling plays an important role in EMT induction and, therefore, contributes to cell invasion and metastasis in cancer. Due to its potential chemopreventative and anti-tumour activities, curcumin has attracted much interest and has been shown to act as a potent EMT inhibitor in various types of cancer. However, at present, the potential effects of curcumin on HGF-induced EMT in OSCC have not been investigated. Here, we demonstrated that HGF signalling could induce EMT in the HSC4 and Ca9-22 OSCC cell lines via the HGF receptor c-Met and downstream activation of the pro-survival ERK pathway. Notably, curcumin inhibited HGF-induced EMT and cell motility in HSC-4 and Ca9-22 cells via c-Met blockade. Therefore, these findings establish curcumin as a candidate drug for OSCC treatment. Furthermore, curcumin was able to effectively inhibit the HGF-induced increase in the levels of vimentin by downregulating the expression of phosphorylated c-Met, an ERK. In conclusion, the results of the present study demonstrated that curcumin was able to reverse HGF-induced EMT, possibly by inhibiting c-Met expression in oral cancer cells, providing a strong basis for the development of novel approaches for the treatment of oral cancer.

Infiltrating angiolipoma of the lower lip: A case report and literature review.

Infiltrating angiolipoma (IAL) is a rare lesion and is a clinicopathological variant of angiolipoma. IAL occurs most commonly in the trunk and extremities, it is rarely found in the head and neck regions and extremely rare in the oral cavity. This study presents the case of a 74-year-old female with IAL of the lower lip. To the best of our knowledge, this is the first case of IAL arising in the lower lip to be reported. Microscopically, IAL was unencapsulated and mature lipocytes were separated by a branching network of proliferating small vessels that infiltrated the adjacent tissues. Therefore, complete excision was difficult to perform. Magnetic resonance imaging has been reported to be valuable in determining the extent of the tumor and asserting a preoperative diagnosis. According to previous studies, the recurrence rate of IAL following surgical extirpation is 35-50%. Furthermore, the levels of mRNA expression of the vascular endothelial growth factor (VEGF) family members in the tumor were investigated. VEGF-A and -B expression were detected, however, VEGF-C and -D were expressed at extremely low levels. Excisional biopsy was performed under local anesthesia. During four years of follow-up, no evidence of tumor recurrence had been identified. An operating microscope may be utilized for the total removal of an IAL to minimize damage to normal tissues. This report indicates that mast cell-derived VEGF may be responsible for the enhanced vascularity in the tumor. We would therefore consider careful extirpation with no wide safety margin to be the procedure of choice, except when the tumor invades irregularly into the muscles.

A rare case of amelanotic malignant melanoma in the oral region: Clinical investigation and immunohistochemical study.

Amelanotic malignant melanoma (AMM) is rare in the oral region. The present study examined the clinical features of this tumor in an attempt to establish diagnostic criteria. The expression of three melanocytic differentiation markers, HMB-45, S-100 and Melan-A, was also measured in primary oral AMMs in order to determine whether the markers could be used to diagnose primary oral AMMs and to find out which marker was the most sensitive. It may be particularly difficult to correctly diagnose AMM that lacks a radial growth phase without immunohistochemical assistance. In the present study, mixtures of polygonal and spindle cells at different ratios were observed in the tumors with and without a radial growth phase. Immunohistochemistry was used to examine the HMB-45, S-100 and Melan-A expression in the formalin-fixed paraffin-embedded specimens of primary oral AMMs. Comparison of staining intensities (SIs) and labeling indices (LIs) of the markers was also performed. The immunostaining results revealed that the SI of Melan-A was significantly higher than that of S-100 (P=0.0011). HMB-45, S-100 and Melan-A also exhibited high positive rates and LIs in AMMs and, therefore, may be good markers for the immunohistochemical diagnosis of primary oral AMMs. Furthermore, Melan-A may be a more sensitive marker than S-100 and HMB-45, as it has a higher SI.

A case of synovial chondromatosis of the temporomandibular joint followed for 17 years.

The patient was a 52-year-old woman who visited our hospital for the chief complaint of a strange sensation in the left temporomandibular joint region on February 22, 1992. On the first examination, crepitus was heard, but no disturbance of mouth opening was noted. On panoramic radiography, radiopaque bodies were present in the left temporomandibular joint region, diagnosed as synovial chondromatosis. Course observation without active treatment was selected. Calcified bodies were noted on the lateral side directly below the left temporomandibular articular tubercle on the first computed tomography image performed in December 1998. Reportedly, this lesion grows slowly, but the lesions started to enlarge at a specific time point during the 17-year follow-up in this patient, showing the necessity of long-term follow-up by imaging even though no quality-of-life reduction or subjective symptom is observed.