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Epigallocatechin-3-gallate (EGCG) and ibuprofen synergistically act to suppress proliferation and enhance apoptosis of prostate cancer cell lines, PC-3 and LNCaP. The purpose of this study was to investigate the mechanism of underlying this synergism. Most interestingly, EGCG + ibuprofen treatment in PC-3 cells resulted in altering the ratio of the splice variants of Bcl-X and Mcl-1, downregulating the mRNA levels of anti-apoptotic Bcl-X(L) and Mcl-1(L) with a concomitant increase in the mRNA levels of pro-apoptotic Bcl-X(s) and Mcl-1(s). However, there were no apparent changes in splicing variants in either ibuprofen or EGCG treated cells. Induction of alternative splicing was correlated with increased activity of protein phosphatase 1 (PP1) in EGCG + ibuprofen-treated cells, since pretreatment with calyculin A and tautomycin blocked EGCG + ibuprofen-induced alternative splicing in PC-3 cells in contrast to pretreatment with okadaic acid. On the other hand, EGCG + ibuprofen treatment in LNCaP cells did not alter splicing variants of Bcl-X and Mcl-1, despite the increase in protein phosphatase activity. In both cell lines, EGCG + ibuprofen inhibited cell proliferation synergistically. Taken together, this study demonstrate for the first time that EGCG + ibuprofen upregulated PP1 activity, which in turn induced alternative splicing of Bcl-X and Mcl-1 in a cell-type specific manner. Our study also demonstrates that the activation of PP1 contributes to the alternative splicing of Mcl-1., (2008 Wiley-Liss, Inc.)

The purpose of this study was to demonstrate gait disturbance after fibular flap transfer using preoperative and postoperative gait analysis. The gait performance of 20 patients was assessed at the Laboratory for Biomechanics, Seoul National University Hospital. Kinematic and kinetic data were collected simultaneously while walking on a 25-m walkway. One month postoperatively, a significant (p<0.05) decrease in the time-distance parameter as well as a significant (p<0.05) decrease in the peak plantarflexion and dynamic range was seen. Only peak plantarflexion in swing was significantly (p<0.05) decreased until 3 months postoperatively. On the basis of the gait analysis results, it was concluded that normalization of the patients' gaits would be expected within 3 months after the operation. There were no permanent pathological changes in the donor site.

A method to produce a desired current pattern in a multiple-source EIT system using voltage sources is presented. Application of current patterns to a body is known to be superior to the application of voltage patterns in terms of high spatial frequency noise suppression, resulting in high accuracy in conductivity and permittivity images. Since current sources are difficult and expensive to build, the use of voltage sources to apply the current pattern is desirable. An iterative algorithm presented in this paper generates the necessary voltage pattern that will produce the desired current pattern. The convergence of the algorithm is shown under the condition that the estimation error of the linear mapping matrix from voltage to current is small. Simulation results are presented to illustrate the convergence of the output current.

Background: One of the green tea components epigallocatechin-3-gallate (EGCG) significantly prevented the growth of prostate cancer cells. In this study, synergistic effect of EGCG and ibuprofen (EGCG+ibuprofen) was investigated to determine their anti-proliferative and pro-apoptotic action in DU-145 prostate cancer cells., Materials and Methods: Cell death analysis, immunoblotting, RT-PCR analysis, and caspase activity assay were used., Results: EGCG+ibuprofen treatment resulted in 90% growth inhibition, while ibuprofen or EGCG alone reduced cell numbers by 25% and 20%, respectively. EGCG+ibuprofen induced MAPK activation, caspase activation and the inhibition of Bfl-1 expression, all of which were blocked by the antioxidant, N-acetyl-L-cysteine (NAC). Moreover, addition of ceramide rescued the NAC-inhibited MAPK activation and pretreatment with the ceramide synthase inhibitor, fumonisin B1, reduced cell death., Conclusion: Our results suggest that in DU-145 prostate cancer cells: (i) EGCG+ibuprofen treatment has a synergistic effect on apoptosis, and (ii) oxidative stress, directly or indirectly via ceramide synthesis mediates pro-apoptotic signaling.

The aim of this study was to determine the appropriate treatment for ameloblastoma by considering the factors associated with recurrence, and to make a quantitative prediction of the risk factors for recurrence. Data on age and gender distribution, location of the tumour, histopathological findings, treatment method, and whether or not patients had a preoperative biopsy confirmation report were collected in 305 cases (239 patients; M: 139, F: 100) of ameloblastoma diagnosed and treated in 1985-2002. After initial statistical evaluation (chi(2)-test and Fisher's exact test), logistic regression analysis was performed to check relative significance and predict recurrence. The disease-free survival function curves of the patients with or without recurrence were obtained by the Kaplan-Meier method and compared using univariate regression analysis. The correlation between recurrence and the treatment method or histopathological type was significant. The differences between the 'conservative' and 'resection with bone margin' and between the 'conservative' and 'segmental resection or maxillectomy' groups in terms of disease-free survival were highly significant. The difference between the 'resection with bone margin' and 'segmental resection or maxillectomy' groups was not significant. A resection with safety margin is the best method to treat most proven ameloblastomas, and conservative treatment is reasonable for patients in their first decade or with unicystic or plexiform ameloblastoma.

Hypoxia inducible factor-1 (HIF-1) is central to most adaptation responses of tumors to hypoxia, and consists of a hypoxia inducible HIF-1alpha or -2alpha subunit, and a constitutively expressed HIF-1beta subunit. Previously, mitochondrial uncouplers, rottlerin and FCCP, were shown to increase the rate of cellular O(2 )consumption. In this study, we determined that mitochondrial uncouplers, rottlerin and FCCP, significantly decreased hypoxic as well as normoxic HIF-1 transcriptional activity which was in part mediated by down-regulation of the oxygen labile HIF-1alpha and HIF-2alpha protein levels in PC-3 and DU-145 prostate cancer cells. Our results also revealed that mitochondrial uncouplers decreased the expression of HIF target genes, VEGF and VEGF receptor-2. Taken together, our results indicate that functional mitochondria are important in HIF-1alpha and HIF-2alpha protein stability and transcriptional activity during normoxia as well as in hypoxia, and that mitochondrial uncouplers may be useful in the inhibition of HIF pathway in tumors.

The purpose of this study was to evaluate the effect of tamoxifen (TAM) when used in combination with cisplatin on oral squamous cell carcinoma (OSCC). For this, the relation between estrogen receptor (ER) expression level and the cytotoxic effect of TAM, the apoptotic effect and its molecular mechanisms of TAM were investigated using OSCC cell lines. Combination treatment demonstrated a superior cytotoxic and apoptotic effect on OSCC cell lines. Considerable amount of ER was detected in some OSCC cell lines, but there were no significant differences of cytotoxic effect of TAM. TAM inhibited PKC activity and up-regulated TGF-beta1 secretion.

The purposes of this study were to examine the correlations between proliferation markers and survival rate in oral squamous cell carcinoma (OSCC) patients, and to evaluate the efficacy of proliferation markers in predicting lymph node metastasis. The patients' age, gender, T score, clinical stage, PCNA and Ki-67 index were analysed. Univariate analysis showed that T score had a significant influence on survival, and stage 4 group had a significantly lower survival rate. Lymph node metastasis was also a significant predictor of survival. Using a cut-off point of 25%, those patients with lower Ki-67 scores had survival advantage over those with higher Ki-67 scores. PCNA did not show any differences in survival with a cut-off point of 50%. Ki-67 and PCNA were significantly higher in the primary tumours associated with lymph node metastasis (pN+) than in those without lymph node metastasis (pN0). Multivariate analysis showed that clinical stage and Ki-67 were independent prognostic factors for survival in OSCC patients. From this result, it can be postulated that the cancer staging based on the TNM stage was a powerful prognostic variable and Ki-67 had a significant effect on the cumulative survival rate.

Oral squamous cell carcinoma (OSCC) accounts for 4.5% of all malignant tumors in Korean males and 3.5% in Korean females. The high recurrence rate, and in particular the high local recurrence rate, constitutes a major therapeutic problem for the Korean population, yet there is a paucity of reports addressing the independent predictors of response and survival rate of OSCC in Korea. The present study was designed to investigate the prognostic value of clinical and demographic data within a set of 861 cases of OSCC in Korea. The medical records of 861 OSCC patients who received treatment between 1984 and 1996 at 22 Korean hospitals were reviewed retrospectively with respect to several patient characteristics, including age at diagnosis, gender, location, TNM stage, and treatment. Independent patient-related and treatment-related factors that significantly influenced disease outcome after treatment were analyzed. To assess the independent factors affecting survival rate, univariate and multivariate regression analyses of the survival data were performed using the Cox proportional hazards model. A tree-structured survival model was also derived using survival tree with unbiased detection of interaction (STUDI). The multivariate Cox regression analysis showed that age, gender, composite stage, and treatment method were significant independent prognostic factors. Radiation dose, stage, size of tumor mass, and age of patient also strongly impacted survival time. OSCC is an extremely malignant carcinoma whose prognostic factors are multiple and complex. Based on the findings of this study, we believe that the prognosis of OSCC might depend directly on cancer stage as determined by the TNM system. Furthermore, the survival rate is positively affected by treatment of the neck upon presentation of the cancer, as this can prevent late neck disease due to persistent growth of occult metastases.

Hypoxia-inducible factor-1, an alphabeta heterodimeric transcription factor, consists of a constitutively expressed HIF-1beta subunit and a hypoxia-inducible HIF-1alpha subunit, and contributes to hypoxia-mediated tumor angiogenesis. Numerous epidemiologic and laboratory studies indicate that green tea has cancer preventive activity which has been attributed to its polyphenol components, the major one being epigallocatechin gallate (EGCG). This study investigated the effect of EGCG on normoxic HIF-1alpha expression in human prostate cancer cells. Surprisingly, we observed an EGCG-induced-dose-dependent increase in HIF-1-mediated transcription and HIF-1alpha protein levels under normoxia. However, concomitant treatment of the prostate cancer cells with EGCG and ferrous ions abolished the increase in HIF-1-mediated transcription that was seen with EGCG treatment alone, suggesting that EGCG may act as a ferrous ion chelator. Furthermore, we determined, for the first time, that EGCG inhibits prolyl hydroxylation of HIF-1alpha, thus preventing HIF-1alpha and pVHL interaction.

Squamous cell carcinoma (SCC) is the most common malignant head and neck tumor and is responsible for more than 90% of head and neck cancers and accounts for 4.5% of all malignant tumors in males and 3.5% in females in South Korea. The purpose of this study was to investigate the correlation of suggested clinico-pathological prognostic factors such as gender, age, T score (T number in TNM), clinical stage, proliferation, invasion index, and lymph node metastasis to the survival of SCC patients in Korea. Furthermore, cytokeratin (CK), carcinoembryonic antigen (CEA), and recently documented apoptosis related protein, survivin, were analyzed by RT-PCR. In 113 patients, survival curves were estimated by the Kaplan-Meier method and nominal or numeric variable influence on survival was studied by Univariate and Multivariate Regression analysis (Cox proportional hazards model). Univariate analysis demonstrated that gender and age factor had no significant effect on survival rate. T score, on the other hand, significantly influenced survival and univariate analysis demonstrated that Stage 4 group had a significantly lower survival rate than the other stage groups but differentiation and invasion index factors had no significant effect on survival rate. Using a 50% cut-off point, patients with lower PCNA scores showed no survival advantages over those with higher PCNA scores but lymph node metastasis was a significant survival predictor in univariate analysis. In addition, lymph node CK and survivin mRNA expression have significant effects on OSCC patient survival rate. This means that prognostic value can be amplified by coincident analysis of T score, pathologically confirmed lymph node metastasis, and lymph node CK or survivin mRNA expression. Multivariate analysis using Cox's proportional hazards model, clinical TNM stage and lymph node survivin mRNA expression were independent OSCC prognostic factors, which support cancer staging based on the TNM as a powerful prognostic variable and lymph node survivin expression might provide predictive information for OSCC patient survival.

One recent application area of EIT is the detection of breast cancer by imaging the conductivity and the permittivity distribution inside the breast. The present "gold standard" for breast cancer detection is X-ray mammography, and it is desirable that the EIT and the X-ray mammography use the same geometry. This work presents a simplified model of the mammography geometry for EIT imaging. The mammography geometry is modeled as a rectangular box with electrode arrays on the top and bottom planes. A forward model for the electrical impedance imaging problem is derived for the homogeneous conductivity distribution and validated by experiment using a phantom tank. The effect of unmodeled surface on the sides of the electrodes is studied.

Oral squamous cell carcinoma (OSCC) is one of the most common head and neck cancers. OSCC generally has a poor prognosis due to its tendency towards local invasion and subsequent metastasis, which is mediated by multiple proteolytic enzymes and angiogenesis. The purpose of this study was to evaluate the anti-cancer effects of genistein, a soybean product known to be an effective natural anti-angiogenic agent, with respect to tumor growth, angiogenesis and in vitro invasion in an OSCC model. Northern blot analysis for vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and matrix metalloproteinase-2 (MMP-2), in vitro invasion assay and gelatin zymography were carried out for HSC-3 cells treated with genistein (27.3 microg/ml). In the animal experiment, genistein (0.5 mg/kg) was injected into tumor (HSC-3)-bearing mice (male balb/c/nu). The tumor growth rate and metastasis to lymph node or lung were compared and the microvessel density (CD31) was subsequently analyzed by immunohistochemistry. The genistein-treated group showed a down-regulation in VEGF mRNA expression, but not in bFGF and MMP-2 mRNA expression. Genistein reduced in vitro invasion through the artificial basement membrane and gelatin zymography also showed a reduced gelatinolytic activity in the genistein-treated group. In the genistein-treated mice, a significantly lower CD31 immunoreactivity was found. However, the tumor growth and metastatic behavior in the experimental group and the control group were similar and there were no significant differences. These results suggest the possible use of genistein as an anti-cancer agent in oral squamous cell carcinoma. However, it appears from the present study that anti-angiogenic therapy consisting of a single application of genistein may not provide a satisfactory treatment for OSCC. As a result, further research is recommended to confirm that genistein may be employed as an adjunct treatment modality for OSCC.

A local invasion and lymph node metastasis (LNM) of an oral squamous cell carcinoma (OSCC) has a poor prognosis, and involves the degradation of the extracellular matrix mediated by multiple proteolytic enzymes including membrane type I-matrix metalloproteinase (MT1-MMP). This study aimed to determine the role of MT1-MMP in OSCC, to evaluate the immunohistochemical expression of MT1-MMP with regard to the invasiveness and LNM of the OSCC, and to evaluate the major source of MT1-MMP mRNA and its protein using immunohistochemistry and in situ hybridization. MT1-MMP expression was examined in 46 OSCCs via immunohistochemistry and non-radioisotope in situ hybridization. The relationship between MT1-MMP expression and LNM, as well as the histological invasiveness, was statistically analyzed. The results showed that whereas 12 out of the 18 OSCCs (66.7%) with LNM showed moderate to strong MT1-MMP expression, only nine of the 28 OSCCs (32.1%) without LNM expressed MT1-MMP strongly. MT1-MMP expression was significantly higher with regard to LNM (P=0.022). As the invasion grade became stronger (from grade a to grade d), MT1-MMP was significantly more strongly expressed (P=0.033). These results suggest that MT1-MMP is primarily secreted in the OSCC cells and is involved in the invasiveness of the OSCC and LNM. Moreover, MT1-MMP combined with other markers may be used to predict the metastatic potential of an OSCC.

Background: Soy isoflavones, genistein, daidzein and glycitein, are thought to have beneficial effects on cancer prevention., Materials and Methods: We used cell cycle analysis, invasion assay and immunoblotting to determine the effects of genistein and glycitein on Jurkat T cells., Results: Glycitein inhibited Jurkat cell invasion at a level comparable to the inhibition by genistein. Both genistein and glycitein down-regulated MMP-13 proteolytic activity by 60-70% and MMP-8 expression. Caffeine could block G2/M arrest by genistein, but was unable to block the inhibition of invasion by genistein and glycitein. We also demonstrated that glycitein inhibited proteintyrosine phosphorylation in Jurkat cells., Conclusion: We determined, for the first time, that glycitein inhibited Jurkat cell invasion, in part through the down-regulation of MMP-13 activity and MMP-8 expression. Our findings also suggest that soy isoflavones may utilize different mechanisms to exert their effects on cell cycle progression and invasiveness of Jurkat cells.

Since it is known that a 307 bp fragment of the position specific regulatory element of human HOXA-7 contains two (DR3 and DR5) retinoic acid response elements (RAREs) at its 3' end, we constructed several deletion constructs containing different numbers of RAREs and examined their effects in vitro and in vivo. The 5' deletion constructs, BM112 and OM213, retaining both RAREs, were highly responsible (about 8 fold induction) for RA in F9 teratocarcinoma cells, versus NM307 (4-5 fold). The construct NS218, with both RAREs deleted but retaining the 5' sequences lost RA responsibility completely, whereas NR271, with one RARE(DR5) deleted retained a 50% inducibility (2.5 fold). In vivo transgenic analysis revealed that the constructs NM307 and NR271, but not OM213 nor BM112, directed the position specific expression pattern. Sequence analysis revealed that HOXA-7 enhancer sequences, including the RARE repeat sequences, were well conserved in human, mouse and chick. Part of the RAREs overlaps with the CDX1 binding site, and sequences of the DR3 RAREs were identical in this species. Two GAGA binding sites were also found to be strictly conserved. Because OM213, which had one GAGA site disrupted but retaining both RAREs, did not direct anterior boundary formation in transgenic mice, these results suggest the importance of the 5' 94 bp region, including the GAGA binding site, in anterior boundary formation and the involvement of the RARE in the rate of expression not in anterior boundary formation.

The purpose of this study was to evaluate the clinical availability of a bisphosphonate in autogenous free bone grafts. Bisphosphonate (0.01 mg/kg/day) was administered daily after an autogenous free bone graft on a rat calvarium. The effects of a bisphosphonate on the resorption of grafted bone and mRNA expression in bone specific genes, i.e. bone morphogenetic protein 2, bone morphogenetic protein 4, alkaline phosphatase, osteocalcin, osteoclast inhibitory factor and calcitonin receptor, were studied via a reverse transcription-polymerase chain reaction (RT-PCR), real time RT-PCR and tartrate-resistant alkaline phosphatase (TRAP) staining. In a clinical and histomorphological review, bone resorption decreased in the experimental group in contrast to the control group where active bone resorption was observed. Bisphosphonate altered not only the mRNA expression of the bone resorption associated genes but also the bone formation associated genes. The expression of the calcitonin receptor (CTR) mRNA was not detected and the osteoclast inhibitory factor (OCIF) was significantly up-regulated in the experimental group as opposed to the control group. The expressions of osteocalcin and alkaline phosphatase mRNAs were also higher in the experimental group. However, there was no significant difference in the mRNA expression of bone morphogenetic proteins between the two groups. The data suggest the possibility of a clinical application of bisphosphonates for decreasing resorption of grafted bone.

Objective: The aim of this study was to compare the total cancellous bone density, bone-implant interface density, and cortical thickness of 6 donor bone types commonly used in oral and maxillofacial reconstruction., Methods: A total of 120 bones from 20 Korean adults-including iliac bones, fibulas, cranial bones, scapulas, ribs, and clavicles-were selected. The implant recipient site was determined by the shape, contour, and anatomical limitations of the bones. The serial cross-sectional images of each bone were then acquired through computed tomography. Total cancellous bone density, bone-implant interface density around the imaginary implant fixture, and the cortical thickness along both sides of the imaginary fixture on each cross-sectional image were evaluated and compared., Results: The cancellous bone density of each donor bone type had a statistically significant difference. The cranial bone showed the highest cancellous bone density, followed by the iliac bone, clavicle, scapula, rib, and fibula (P <.05). The bone-implant interface density of the cranial bone, clavicle, fibula, and scapula each belonged to the same Duncan's group, whereas the rib and iliac bone showed lower bone-implant interface density. In average cortical thickness, the scapula and fibula had a thicker cortex surrounding the imaginary implant than the other bones, and the rib had the thinnest cortex., Conclusion: Although more extensive testing is needed to explain the clinical implications of these results, the findings of this study may help clinicians choose the most appropriate donor bone.

Odontogenic keratocyst (OKC) is of particular interest because of its high recurrence rate and aggressive behavior. Two hundred fifty-six cases of OKC were reviewed for the age of the patient at diagnosis, sex of the patient, OKC location, and radiographic findings, and 132 patients with OKC were observed to estimate recurrence, which was analyzed for age, sex, location, and several histopathologic findings. OKCs occurred more frequently in men (58.6%) than in women (41.4%), and they occurred in patients within a wide age range, most commonly in patients in the third decade of life (28.9%), followed by those in the second decade (25.0%); the mean age of patients with OKC was 30.8 years. One hundred ninety-six of the 256 cases (76.5%) occurred in the mandible, and the other 60 cases (23.5%) occurred in the maxilla. The mandibular molar and the premolar areas (51.2%) were the most common sites, and the most frequent clinical manifestations at first admission were swelling, pain, or both (82.4% of total cases). Radiographic impressions included dentigerous cyst (27.3%), OKC (25.4%), primordial cyst (14.8%), ameloblastoma (11.7%), residual cyst (9.8%), and radicular cyst (3.1%). The frequency of recurrence at the follow-up examination was 58.3%. There was no significant difference in the recurrence rate on the basis of the sex of the patient. However, OKCs had a significantly higher recurrence rate in patients in the fifth decade of life than in patients in the other age groups (P = .005).Recurrence rates were significantly dependent on the sites of involvement, and OKCs in the mandibular molar region had significantly higher recurrence rates than those in other sites (P = .001). The histopathologic presence of one or more daughter cysts was significantly related to recurrence (P = .03).

Angiogenesis is an essential process for the growth and invasion of cancer. However, it is uncertain that anti-angiogenic effects can be a major treatment strategy of oral cancer. The aim of this study was to investigate whether thalidomide and paclitaxel, which are known to be potent inhibitors of angiogenesis, have inhibitory effects on the growth of oral squamous cell carcinoma (OSCC) xenotransplanted into nude mice and whether anti-angiogenesis can be included as a major treatment strategy of oral cancer. After human OSCC cell line, KB, was subcutaneously inoculated into 32 nude mice, the volume of tumor was measured every 3 days. When the tumor mass reached 300-500 mm3, thalidomide (200 mg/kg) and paclitaxel (13 mg/kg) were administered into the animals and tumor volume change was checked. The excised tumor masses on the 30th day after administration were frozen and processed for immunohistochemistry using vascular endothelial growth factor (VEGF) and CD31, and for real-time reverse transcription-polymerase chain reaction (RT-PCR). We evaluated VEGF expression and the expression of its mRNA and CD31 for vessel density. Paclitaxel showed an inhibitory effect on the growth of transplanted human OSCC and reduced the immunohistochemical expression of VEGF and CD31 and VEGF mRNA (P<0.01). Thalidomide also lowered remarkably VEGF expression (P<0.01) and CD31 (P<0.01) as well as VEGF mRNA (P<0.05), but it did not show statistically significant inhibitory effect on the tumor growth. These results suggest that the growth of human OSCC is not simply dependent on VEGF-induced angiogenesis and that anti-angiogenic therapy alone is not likely to be effective for the treatment of OSCC, but might be regarded as adjuvant chemotherapeutic strategy.