Hidetaka Shimizu

The effects of trichostatin A on the oncolytic ability of herpes simplex virus for oral squamous cell carcinoma cells

Combining the use of a chemotherapeutic agent with oncolytic virotherapy is a useful way to increase the efficiency of the treatment of cancer. The effect of the histone diacetylase (HDAC) inhibitor trichostatin A (TSA) on the antitumor activity of a herpes simplex virus type-1 (HSV-1) mutant was examined in oral squamous cell carcinoma (SCC) cells. Immunoblotting analysis and immunoflourescence staining revealed that a cytoplasmic nuclear factor-κB (NF-κB) component, p65, translocated into the nucleus after infection with γ134.5 gene-deficient HSV-1 R849, indicating that R849 activated NF-κB. TSA induced acetylation of p65 and increased the amount of p65 in the nucleus of oral SCC cells. Treatment of R849-infected cells with TSA also increased the amount of nuclear p65 and binding of NF-κB to its DNA-binding site and an NF-κB inhibitor SN50 diminished the increase in nuclear p65. In the presence of TSA, the production of virus and the expression of LacZ integrated into R849 and glycoprotein D, but not ICP0, ICP6 and thymidine kinase, were increased. The viability of cells treated with a combination of R849 and TSA was lower than that of those treated with R849 only. After treatment with TSA, expression of the cell cycle kinase inhibitor p21 was upregulated and the cell cycle was arrested at G1. These results indicate that TSA enhanced the replication of the HSV-1 mutant through the activation of NF-κB and induced cell cycle arrest at G1 to inhibit cell growth. TSA can be used as an enhancing agent for oncolytic virotherapy for oral SCC with γ134.5 gene-deficient HSV-1.

Bilateral multiple spindle cell lipomas of the tongue

Spindle cell lipoma (SCL) typically occurs in elderly men as a solitary lesion in the posterior neck and back, but less commonly also involves the oral cavity. Here, we describe a rare case of bilateral multiple SCLs of the tongue. The patient was a 72-year-old Japanese man with multiple painless soft nodules in the bilateral margins of the tongue. The patient was not obese, and had used alcohol moderately for more than 40 years. A clinical diagnosis of multiple tongue lipomas was made. The tumors were resected surgically, and they exhibited the histopathological features of SCL, composed of mature fat cells, collagen-forming CD34-positive spindle cells, and sparse mast cells. This suggests that differential diagnosis of intraoral multiple lipomatous nodules should include not only lipomatosis but also multiple SCLs, notwithstanding the rare incidence of the latter.

Maxillary Distraction Osteogenesis in Cleft Lip and Palate Patients With Skeletal Anchorage

Objective: Maxillary distraction osteogenesis with the rigid external distraction (RED) system has been used to treat cleft lip and palate (CLP) patients with severe maxillary hypoplasia. We introduce maxillary distraction osteogenesis for CLP patients with skeletal anchorage adapted on a stereolithographic model. Patients: Six maxillary deficiency CLP patients treated according to our CLP treatment protocol had undergone maxillary distraction osteogenesis. Method: In all patients, computed tomography (CT) images were recorded preoperatively, and the data were transferred to a workstation. Three-dimensional skeletal structures were reconstructed with CT data sets, and a stereolithographic model was produced. On the stereolithographic model, miniplates were adapted to the surface of maxilla beside aperture piriforms. The operation performed involved a high Le Fort I osteotomy with pterygomaxillary disjunction. Miniplates were fixed to the maxillary segment with three or four screws and used for anchorage of the RED system. Retraction of the maxillary segment was initiated after 1 week. Results: The accuracy of the stereolithographic models was enough to adapt the miniplates so that there was no need to readjust the plates during surgery. Postoperative cephalometric analysis showed that the direction of the retraction was almost parallel to the palatal plane, and dental compensation did not occur. Conclusions: We performed maxillary distraction osteogenesis with skeletal anchorage adapted on the stereolithographic models. Excellent esthetic outcome and skeletal advancement were achieved without dentoalveolar compensations.

C-arm-guided reduction of zygomatic fractures revisited.

BACKGROUND Anatomic reduction of the zygomatic arch, a key surgical landmark for midfacial width and projection, is essential for the treatment of combined fractures of the zygomaticomaxillary complex and zygomatic arch. Reduction control in surgery for this common facial fracture would be facilitated by intraoperative real-time assessment using widely available and reliable equipment. Although C-arm fluoroscopy is routinely used in the repair of orthopedic fractures, its use in the maxillofacial region, particularly for combined zygomatic fractures, has been scarcely reported. METHODS We prospectively evaluated C-arm-guided reduction in 38 patients of combined zygomatic fracture without concurrent craniofacial fractures. Patients were classified according to the presence or absence of bone contact in the displaced zygomatic arch, namely as conserved (C) and loss (L) types, respectively. Reduction status was determined by the degree of recovery of the malar prominence and arch shape. RESULTS In all cases, C-arm imaging clearly displayed the displaced zygomatic arch and body in a single image. Cumulative fluoroscopic time was a few minutes in all cases. Total reduction status was excellent in 21 patients and good in 17. No case was classified as fair or poor. Repair was significantly more favorable in type C than in type L cases (p = 0.0016). CONCLUSIONS In combined zygomatic fractures, the C-arm technique provides easy, flexible, and time-efficient adjustment. Its comprehensive imaging for zygomatic arch shape and body contour markedly facilitates the control of fracture reduction and protects against unexpected, unsatisfactory outcomes.

Involvement of RhoA and RalB in geranylgeranyltransferase I inhibitor-mediated inhibition of proliferation and migration of human oral squamous cell carcinoma cells.

PurposeGeranylgeranyltransferase I is required for the prenylation of the small GTPases. The effect of GGTase I inhibitors (GGTIs) on oral squamous cell carcinoma (SCC) cells was examined.MethodsThe GGTI-treated cells were examined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay, flow cytometric analysis, transwell chamber assays, and immunofluorescent staining. Small GTPases were detected by immunoblot analysis, and siRNA were used for silencing RalA and RalB.ResultsGGTI suppressed the proliferation of oral SCC cells and induced cell cycle arrest at G1, but the sub-G1 fraction was small. The expression of the cyclin-dependent kinase (CDK) inhibitor p21Waf1/Cip1, but not p27Kip1, was markedly increased by GGTI. There was an apparent increase in the expression and reduction in the membrane localization of RhoA and RalB, but not Ras and RalA. Assays with transwell chambers and wound healing and invasion revealed the migrative and invasive capabilities of SAS cells to be inhibited by GGTI. Actin filaments were rearranged and stress fibers and peripheral cell processes were lost, accompanying cell rounding. siRNA for RalB, but not RalA, significantly suppressed the migration of SAS cells.ConclusionThese results suggest that GGTI inhibits the geranylgeranylation of RhoA and increases the p21Waf1/Cip1 level, resulting in cell cycle arrest at G1 to decrease cell proliferation, and that of RalB to suppress the migration and invasion by oral SCC cells. GGTIs may be useful as inhibitors of invasion and metastasis in cases of oral SCC.