Akihiko Oyama

Simvastatin inhibits growth via apoptosis and the induction of cell cycle arrest in human melanoma cells.

Competitive inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A reductase (the statins) that inhibit the synthesis of mevalonic acid are in wide use for treatment of hypercholesterolemia. Although antitumor effects on a variety of cell types have been reported for statins, the effect of simvastatin (one of the statins) on human melanoma cell lines is not known. Here, we report antitumor effects of simvastatin on human melanoma cell lines. We treated human melanoma cell lines, A375M, G361, C8161, GAK, and MMAc with simvastatin in various concentrations for 1 to 3 days. To investigate the antitumor effect of simvastatin, we analyzed cell viability, morphologic changes, reversibility of inhibition by geranylgeranyl pyrophosphate and farnesyl pyrophosphate, apoptosis and the cell cycle. Simvastatin treatment reduced cell viability in all five melanoma cell lines. The different melanoma cell lines, however, displayed different sensitivities to simvastatin. The addition of geranylgeranyl pyrophosphate to A375M and G361 cells in the presence of simvastatin completely restored the viability of cells, but the addition of farnesyl pyrophosphate did not. DNA fragmentation assay showed that simvastatin induced apoptosis in A375M and G361 cells. Simvastatin caused a G1 arrest in G361 and MMAc cells. Consistent with the cell cycle arrest, simvastatin caused an increase in the mRNA levels of p21 and p27 on G361 and MMAc cells.We conclude that simvastatin has an antitumor effect on human melanoma cells in vitro via apoptosis and cell cycle arrest. These results suggest that simvastatin may be an effective anticancer drug for malignant melanoma.

Sentinel lymph node biopsy using real-time fluorescence navigation with indocyanine green in cutaneous head and neck/lip mucosa melanomas.

The triple technique (lymphoscintigraphy, patent‐blue staining, and a gamma probe) constitutes a reliable method for the sentinel lymph node (SLN) biopsy. However, in head and neck melanomas, a shine‐through phenomenon, which occurs because these SLNs are close to the primary focus, is irreversibly problematic. To get around the shine‐through phenomenon, this study uses the fluorescence navigation with indocyanine green (ICG) as well as the triple technique.

A New Uniform Protocol of Combined Corticosteroid Injections and Ointment Application Reduces Recurrence Rates After Surgical Keloid/Hypertrophic Scar Excision

BACKGROUND Published reports indicate that corticosteroid injections can prevent recurrence after keloid excision, but the side effects of repetitive intralesional steroid injections may preclude treatment maintenance. Additionally, few of these studies employed a standardized treatment protocol. OBJECTIVES To analyze the results of a new uniform treatment protocol combining corticosteroid injections and ointment application designed to reduce recurrence rates after excisional surgery in individuals with keloids or hypertrophic scars. METHODS As a standard procedure, the first corticosteroid injection took place after removal of the sutures and then once every 2 weeks after that until it had been done five times. In addition, all postsurgical wounds received self‐administered steroid ointment application twice daily for 6 months after suture removal. RESULTS Postoperative follow‐up in this series ranged from 24 to 57 months (median 32 months, mean 32.5 months). Recurrence occurred in three of the 21 keloid cases (14.3%) and one of the six hypertrophic scar cases (16.7%). CONCLUSION We evaluated a new standardized adjuvant corticosteroid therapy to prevent recurrence after surgical keloid or hypertrophic scar excision. Using this method, we achieved low recurrence rates.

Microsurgical lymphaticovenous implantation targeting dermal lymphatic backflow using indocyanine green fluorescence lymphography in the treatment of postmastectomy lymphedema.

Background: Microsurgical lymphaticovenous implantation in lymphedema is done to create a lymphaticovenous shunt by an implantation of collecting lymphatics into the small vein, as reported previously. The authors have recently introduced ultrasonograpy and indocyanine green fluorescence lymphography into this procedure. Methods: Nine cases of postmastectomy lymphedema had received preoperative venous marking using ultrasonography and lymphatic mapping using indocyanine green fluorescence lymphography. The concept of modification is to pick up the most effective point for microsurgical lymphaticovenous implantation that involves both subcutaneous veins and the dermal backflow of excess lymphatics. Objective improvement was analyzed by the percent reduction of edema circumference at two points of the affected forearm. Results: Preoperative lymphography showed a spotty image for dermal backflow in all nine extremities, a linear image on the dorsal hand in six extremities, and a linear image on the forearm in three extremities. With an average follow-up of 17 months, three patients had excellent results with the reduction of edema circumference more than 50 percent for both the distal and proximal sites of the treated forearm. Four patients had good results with the reduction of edema circumference more than 50 percent at the distal or proximal sites, two patients had fair results, and no patients had poor results. The average number of modified microsurgical lymphaticovenous implantations was 3.7 per case. Conclusion: Modified microsurgical lymphaticovenous implantation is expected to provide favorable results with a minimum number of these modified implantations, even though no linear lymph channel was detected by preoperative indocyanine green fluorescence lymphography.

A new model of acquired lymphedema in the mouse hind limb: a preliminary report.

Abstract Lymphedema is known to be caused by many pathologic conditions; however, its correct diagnosis and optimal therapeutic strategies remain to be established. In this report, we describe an experimental model for acquired lymphedema in the lower extremity of the mouse that creates a lymphatic block in the groin induced by both radiation treatment and surgical division of the superficial and deep lymphatics. To evaluate the lymphatic system in this model, an indocyanine green fluorescence-sensitive camera system was used. This model has the advantages of relative technical simplicity and cost-effective use of a rodent animal model. Furthermore, a greater range of research tools such as antibodies and various databases are available for mice. This mouse model may be useful to anyone modeling lymphedema mechanisms, by providing a defined molecular context.

New grading system for patients with treacher Collins syndrome.

Treacher Collins syndrome (TCS) is a congenital, craniofacial disorder affecting the development of structures derived from the first and second branchial arches. The associated clinical features and their severity are variable. Therefore, we reasoned that objective assessment of the clinical features and their severity in TCS is necessary to plan the treatment and to evaluate the outcome. We hereby propose a new grading system for Treacher Collins syndrome (TCS). Since 1978, 16 patients have been diagnosed with TCS. Eleven out of the 16 TCS patients, for whom we were able to estimate the severity of the clinical features in each region, and to make an objective assessment of the therapeutic outcomes, were selected. By allocating points according to the degree of severity of the clinical features in each region, then summing them up and categorizing them, we classified the overall clinical features into 3 grades. The severity increases from grades I to III. In summary, there were 3 patients of grade I, 4 patients of grade II and 4 patients of grade III. Distinctive differences regarding the degree of severity of the clinical features were clearly observed between each grade. We propose a new TCS grading system and applied it to 11 patients. We believe that this system may be useful for planning treatment and to evaluate the outcome in TCS patients.

How do the type and location of a vascular malformation influence growth in Klippel-Trénaunay syndrome?

Background: Although Klippel-Trénaunay syndrome is a mixed vascular malformation characterized by abnormal growth in the extremities, no uniform diagnostic criteria have been established because of the variety in its manifestation. Consequently, no anatomical analysis based on a comparison study has been reported. In this study, the authors determine the frequency of various vascular malformations and abnormal growth and assess any statistical relationship between vascular malformation type/location and abnormal growth in terms of length and girth. Methods: Thirty-five patients with Klippel-Trénaunay syndrome satisfying the criteria proposed by Oduber et al. in 2008 were enrolled. The type and location of the vascular malformation and abnormal circumferential growth were assessed by magnetic resonance imaging and ultrasonography. Bone girth was assessed by axial magnetic resonance imaging/computed tomography. Plain radiographs of the long bones were used to measure growth in length. Results: The spectrum of vascular types was similar to that in previous reports. There was no significant association between leg length and vascular malformation type or location. Leg bone circumferential hypoplasia was observed in 50 percent of cases and was significantly related to the presence of intramuscular lesions. A single venous malformation in the subcutaneous tissue was significantly associated with the presence of subcutaneous hypertrophy. Patients with intramuscular lymphatic malformations had a significantly higher frequency of muscle hypoplasia. Conclusion: The type and location of certain vascular malformations were significantly associated with abnormal subcutaneous tissue, muscle, and bone growth.

Treg-enriched CD4+ T cells attenuate collagen synthesis in keloid fibroblasts

Keloid is an inflammatory and fibrotic disease with an unknown pathogenesis. Regulatory T cells (Tregs) of CD4+ lineage can suppress other effector CD4+ T cells and modulate the immune response. A relative decrease in the number of Tregs may be involved in the pathogenesis of inflammatory and fibrotic diseases. We therefore investigated the number of Tregs in keloids using immunohistochemistry and examined the interaction between Tregs and keloid fibroblasts (KFs) using a coculture system. It was found that the ratio of Tregs/CD4+ T cells was lower compared with that in other common inflammatory skin conditions. In addition, Treg‐enriched CD4+ T cells reduced collagen synthesis by KFs. Our findings suggest that a local imbalance of Tregs contributes to the development of keloids and that correction of this imbalance might represent a novel therapeutic approach to keloid fibrosis.

Pathophysiological Characteristics of Melanoma In-Transit Metastasis in a Lymphedema Mouse Model

In-transit metastasis (ITM) is a unique manifestation of intralymphatic tumor dissemination, characterized by the presence of melanoma cells between the primary lesion and the draining regional lymph node basin that is clinically associated with poor prognosis. In this study, we aimed to establish an experimental animal model of melanoma ITM, as research progress in this field has been hampered by a lack of suitable experimental models. We reproduced melanoma ITM in a mouse hind limb by transplanting melanoma cells into the footpad of a mouse with lymphedema (LE). The tumor cells at the ITM site were highly proliferative, and mice with ITMs were more likely than control mice to develop distant lymph node and lung metastases. Peritumoral lymphatic vessels and tumor-associated blood vessels were increased in the primary tumor site of the LE mice. Our established ITM melanoma mouse model enabled us to clarify the molecular determinants and pathophysiology of ITM. This ITM model is also comparable to the unfavorable clinical behavior of melanoma ITM in humans and, moreover, underlined the importance of lymphangiogenic factors in the tumor dissemination through the lymphatic system.

Velopharyngeal insufficiency in hemifacial microsomia: Analysis of correlated factors

OBJECTIVE: To investigate the incidence of unilateral hypodynamic palate (UHP) and velopharyngeal insufficiency (VPI) in hemifacial microsomia (HFM), and to determine the dysmorphic manifestations having significant associations with UHP/VPI in HFM. STUDY DESIGN: This was a nonrandomized study of 48 patients with unilateral HFM without cleft palate. The correlation between each anomaly and UHP/VPI was analyzed statistically. In addition, we observed 4 HFM patients with cleft palate to examine the influence on cleft palate speech. RESULTS: The incidence of UHP in HFM was 50.0% and that of VPI was 14.6%. All the VPI patients had UHP. Severe micrognathia and soft tissue deficiency, macrostomia, and mental retardation were significant risk factors for developing VPI in HFM. Moreover, UHP exacerbated speech in HFM with cleft lip and palate. CONCLUSIONS: Significant correlations were detected between VPI and HFM. This finding should be helpful in the overall management of HFM.