Differential outcomes of jaw bone position after surgical-orthodontic treatment in three types of skeletal Class III asymmetry patients.

BACKGROUND/PURPOSE: Facial asymmetry is common in Class III patients requiring orthognathic surgery. This study aimed to analyze jaw bone position after surgical-orthodontic treatment in three types of skeletal Class III asymmetry patients. METHODS: The retrospective study included 30 Class III patients who underwent surgical-orthodontic treatment comprising LeFort I osteotomy and bilateral sagittal split osteotomy (BSSO) without genioplasty. Cone-beam computed tomography (CBCT) images obtained before surgery (T1) and after post-surgical orthodontic treatment (T2) were superimposed with voxel-based registration. Patients were classified into three groups based on T1 CBCT scans. Groups 1 and 2 exhibited menton and ramus deviated to the same side. Menton deviation was larger than ramus width asymmetry in group 1, while the reverse was true for group 2. Group 3 had menton deviation contralateral to the side with greater ramus width. RESULTS: Menton deviation after treatment was improved in all groups. Ramus width asymmetry and coronal ramus angle difference decreased in groups 1 and 2. Neither improvement nor deterioration of ramus width asymmetry was noted for group 3. Comparing to groups 1 and 2, group 3 had greater roll and yaw rotations of distal segment, more upward pitch of proximal segment on chin deviation side, and largest inward yaw as well as backward translation of proximal segment on non-deviation side. CONCLUSION: The positional changes of osteotomy segments differed among three types of mandibular asymmetry. Special attention should be given to the atypical mandibular asymmetry with mandibular body and ramus deviating to opposite directions during surgical correction of jaw deflection.

Sirtuin 6 ameliorates arthritis through modulating cyclic AMP-responsive element binding protein/CCN1/cyclooxygenase 2 pathway in osteoblasts.

INTRODUCTION: CCN1 is an immediate-early gene product pivotal for arthritis progression. We have previously shown that sirtuin 6 (SIRT6) inhibited hypoxia-induced CCN1 expression in osteoblasts. Herein we examined the contribution of cyclic AMP-responsive element binding protein (CREB)/CRE to this suppressive action and the influence of CCN1 on cyclooxygenase (COX) 2 synthesis. MATERIALS AND METHODS: MC3T3-E1 murine osteoblasts were cultured under normoxia (21% oxygen) or hypoxia (2% oxygen). Expressions of CCN1, phospho-CREB (Ser133), COX2 and relevant kinases were assessed by Western blot. SIRT6 was overexpressed in cultured osteoblasts and arthritic joints by a lentiviral-based technique. Activities of CCN1 gene promoter constructs were examined by luciferase reporter assay. Interaction between CREB and CCN1 promoter was assessed by chromatin immunoprecipitation (ChIP). Collagen-induced arthritis (CIA) was established in 20 rats to evaluate the effects of SIRT6 therapy on osteoblastic expressions of phospho-CREB, CCN1 and COX2. RESULTS: SIRT6 suppressed hypoxia-enhanced CCN1 expression and CREB phosphorylation. Attenuation of calcium/calmodulin-dependent protein kinase II (CaMKII) may be responsible for SIRT6-induced CREB inhibition. CRE at - 286 bp upstream of the ATG start codon was essential for CCN1 expression under hypoxia and SIRT6 reduced hypoxia-stimulated CREB/CRE interaction. Forced expression of CREB rescued SIRT6-suppressed CCN1 synthesis. CCN1 induced COX2 expression in osteoblasts. In rat CIA, the therapeutic effect of SIRT6 was accompanied by decreases in osteoblastic expressions of phospho-CREB, CCN1 and COX2. CONCLUSION: Our study indicated that the benefits of SIRT6 to inflammatory arthritis and bone resorption are at least partially derived from its modulation of CREB/CCN1/COX2 pathway in osteoblasts.

Occlusal function and electromyographic activity of masticatory muscles in skeletal Class III patients with different patterns of mandibular asymmetry.

BACKGROUND: Although jaw asymmetry is commonly seen in skeletal Class III patients, its correlation with occlusal function and masticatory muscle activity has not been fully elucidated. OBJECTIVES: The purpose of this study was to investigate the occlusal function and masticatory muscle activity in skeletal Class III patients with various patterns of mandibular asymmetry. METHODS: Forty-two patients and 10 normal participants were examined. The patients were categorised into three groups. Groups 1 and 2 exhibited menton and ramus deviation to the same side. Menton deviation was larger than ramus deviation in Group 1, whereas Group 2 showed the inverse relation. Group 3 patients showed menton and ramus deviation in opposite directions. Occlusal contact area (OCA), relative bite force (RBF), and temporalis anterior (TA) and masseter muscle (MM) activity at maximum clenching were measured using T-Scan Novus system and Bio-EMG-III. Statistical analysis was performed using the t-test, one-way analysis of variance with Bonferroni correction and Spearman correlation (α = .05). RESULTS: Compared with normal participants, the patients had smaller OCA and greater asymmetry in the distribution of masticatory muscle activity. Greater ramus deviation was associated with smaller OCA in Group 1 but with larger OCA in Group 3. In Group 1, greater menton deviation was related to stronger TA activity on the non-deviation side. In Group 2, greater ramus deviation was related to stronger MM activity on the deviation side. CONCLUSION: Deviation of the menton and ramus was individually related to OCA and masticatory muscle activity, and this relationship varied according to the pattern of mandibular asymmetry.

Prognosis of medication-related osteonecrosis of the jaws in metastatic prostate cancer patients.

OBJECTIVES: The aim of this study was to find out the prognosis of medication-related osteonecrosis of the jaws (MRONJ) in prostate cancer patients who received two different types of antiresorptive agents for bone metastasis. MATERIALS AND METHODS: We retrospectively surveyed a cohort of 95 metastatic prostate cancer patients with 122 MRONJ lesions treated in a single medical center. Treatment outcomes and prognostic factors were investigated. The cumulative complete response rate was calculated with the Kaplan-Meier method, and significance was examined with the log-rank and Breslow tests. Cox regression was used for the univariate and multivariate analyses of prognostic factors. RESULTS: The cumulative complete response rate of all patients at 12 months was 37.8%, and that of patients treated with zoledronic acid and denosumab was 22.9% and 70.5%, respectively. Denosumab, pretreatment C-terminal telopeptide of collagen I (CTX) level > 150 pg/ml, and anemia were identified as independent prognostic factors in a multivariate analysis with adjusted hazard ratios of 3.18 (95% confidence interval [CI], 1.24-8.11), 3.24 (95% CI, 1.39-7.53), and 0.42 (95% CI, 0.19-0.93), respectively. CONCLUSION: A higher pretreatment level of CTX, using denosumab as the antiresorptive agent and without anemia, indicates a better treatment outcome of MRONJ in prostate cancer patients.

Differences of condylar changes after orthognathic surgery among Class II and Class III patients.

BACKGROUND/PURPOSE: The nature of susceptibility to condylar resorption after orthognathic surgery can be different between skeletal Class II and Class III populations, which was addressed by few in the past. The aim of the present study was to use cone-beam computed tomographic (CBCT) images to investigate the displacement and morphological changes of temporomandibular joints (TMJs) in patients received orthodontic treatment combined with orthognathic surgery. METHODS: Both Class III (n = 34) and Class II (n = 17) patients were compared through overall and regional superimpositions of the initial and posttreatment CBCTs. Two-sample t-test was used to identify significance between group differences. Pearson's correlation coefficient was used to address changes of TMJ and the amount of setback or advancement. RESULTS: The axial ramal angle increased significantly in Class III group and decreased in Class II groups after orthognathic surgery (p < FDR_p). For condylar dimensions, significant widths and lengths reductions were noted only in Class II group. However, no significant difference was found after comparing subgroup differences according to one-jaw and two-jaw options, nor any significant correlation found between the condylar changes and the amount of surgical movements. CONCLUSION: The nature of condylar susceptibility could result more from different skeletal patterns than the amount of surgical movements. However, the direction of mandibular surgery may contribute to different changes of condylar angle in axial section.

The possible role of sirtuin 5 in the pathogenesis of apical periodontitis.

OBJECTIVES: We investigated the relation between expression of sirtuin 5 (SIRT5) in osteoblastic cells and progression of apical periodontitis. The role of SIRT5 in hypoxia-induced reactive oxygen species (ROS) formation and osteoblast apoptosis was also examined. MATERIALS AND METHODS: Progression of rat apical periodontitis was monitored by conventional radiography and microcomputed tomography. SIRT5 and oxidative stress biomarker 8-OHdG in bone-lining cells were assessed by immunohistochemistry. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling was used to demonstrate apoptosis. In primary human osteoblasts cultured under hypoxia, Western blot was used to analyze SIRT5 expression and cleavage of pro-caspase 3 and poly(ADP-ribose) polymerase (PARP). SIRT5 was overexpressed through lentiviral technique. ROS formation and mitochondrial membrane potential changes were assessed by MitoSOX-Red and JC-1 fluorescence, respectively. Immunofluorescence microscope was used to evaluate mitochondrial release of cytochrome c. RESULTS: In rat apical periodontitis, disease progression was accompanied by decreased expression of SIRT5, increased oxidative stress, and enhanced apoptosis in bone-lining cells. SIRT5 was suppressed in cultured osteoblasts under hypoxia. SIRT5 overexpression ameliorated hypoxia-enhanced ROS formation, mitochondrial depolarization, cytochrome c leakage, activation of caspase-3, and PARP fragmentation. CONCLUSIONS: SIRT5 is able to alleviate hypoxia-enhanced osteoblast apoptosis. SIRT5 augmentation may have therapeutic potential for apical periodontitis.

Prognosis of medication-related osteonecrosis of the jaws in cancer patients using antiresorptive agent zoledronic acid.

BACKGROUND/PURPOSE: Anti-resorptive agents are commonly used in cancer patients with bone metastasis or multiple myeloma (MM). An adverse event termed medication-related osteonecrosis of the jaws (MRONJ) was discovered in patients using these agents but relatively little attention has been paid to its prognosis. Our aims were to find out the treatment outcomes and prognostic indicators of MRONJ in cancer patients who received zoledronic acid as antiresorptive therapy. METHODS: We retrospectively surveyed a cohort of 133 cancer patients who received zoledronic acid. A total of 150 MRONJ lesions were included for investigation. Cumulative complete response rate after treatment was calculated with the Kaplan-Meier method, and significance was examined with the log-rank tests. Cox regression was used for univariate and multivariate analyses of prognostic factors. RESULTS: The cumulative complete response rate of all patients at 24 months was 53.2%, and those of patients with MM, breast cancer and prostate cancer were 27.8%, 60.7% and 68.0%, respectively. Having MM was identified as an independent prognostic factor in a multivariate analysis with adjusted hazard ratios of 0.28 (95% confidence interval, 0.09-0.83). CONCLUSION: For cancer patients with ONJ related to zoledronic acid, patients with MM endure a worse treatment outcome.

Upregulation of vascular endothelial growth factor mRNA level is significantly related to progression and prognosis of oral squamous cell carcinomas.

BACKGROUND/PURPOSE: Vascular endothelial growth factor (VEGF) is a potent angiogenic factor. This study evaluated whether the VEGF mRNA level in oral squamous cell carcinoma (OSCC) tissue could be a biomarker to predict the progression and prognosis of OSCCs in Taiwan. METHODS: This study used quantitative real-time reverse transcription-polymerase chain reaction (quantitative RT-PCR) to detect the VEGF mRNA levels in 60 OSCC specimens. Threshold cycle (CT) was defined as the PCR cycle number needed to generate a predetermined amount of DNA (threshold). The relative amount of tissue VEGF mRNA, standardized against the amount of glyceraldehyde 3-phosphate dehydrogenase (GAPDH) mRNA, was expressed as ΔCT = (VEGF CT - GAPDH CT). For a chosen threshold, a smaller starting copy number of mRNA results in a higher CT value. Thus, the lower the ΔCT, the greater the copy number of VEGF mRNA in tissues. RESULTS: The lower mean VEGF mRNA ΔCT value was significantly associated with OSCCs with larger tumor size (p = 0.040), positive lymph node metastasis (p = 0.023), and more advanced clinical stages (p = 0.008). VEGF mRNA ΔCT value < 4.2 (p = 0.026) was identified as an independent unfavorable prognosis factor using multivariate regression analyses. Moreover, Kaplan-Meier curve showed that OSCC patients with a VEGF mRNA ΔCT value < 4.2 had a significantly poorer overall survival than those with a VEGF mRNA ΔCT value ≥4.2 (log-rank test, p = 0.0427). CONCLUSION: The OSCC tissue VEGF mRNA level can be used to predict the progression and prognosis of OSCCs in Taiwan.

Simvastatin inhibits cysteine-rich protein 61 expression in rheumatoid arthritis synovial fibroblasts through the regulation of sirtuin-1/FoxO3a signaling.

OBJECTIVE: To examine the role of sirtuin-1 (SIRT-1)/FoxO3a in the expression of cysteine-rich protein 61 (CYR-61) in rheumatoid arthritis synovial fibroblasts (RASFs) and the influence of simvastatin on this pathway, and to determine the relationship between disease progression and FoxO3a/CYR-61 signaling in synovial fibroblasts in vivo using a rat model of collagen-induced arthritis (CIA). METHODS: In RASFs, the expression of CYR-61 and SIRT-1, the localization of FoxO3a in the nucleus/cytoplasm, and the phosphorylation/acetylation of FoxO3a were examined by Western blotting. Secretion of CCL20 was assessed by enzyme-linked immunosorbent assay. Promoter activity of the Cyr61 gene was evaluated by luciferase assay, with or without forced expression of FoxO3a and SIRT-1 by lentiviral transduction. FoxO3a-Cyr61 promoter interaction was examined by chromatin immunoprecipitation. In rats with CIA, the expression of CYR-61 and phosphorylated FoxO3a in synovial fibroblasts was examined by immunohistochemistry. RESULTS: In RASFs, simvastatin suppressed the tumor necrosis factor α (TNFα)-induced production of CYR-61 and CCL20. Nuclear levels of FoxO3a were decreased after TNFα stimulation of RASFs, and forced expression of FoxO3a reversed the inductive effects of TNFα on CYR-61. Simvastatin inhibited the nuclear export, phosphorylation, and acetylation of FoxO3a and maintained its binding to the Cyr61 promoter. Forced expression of SIRT-1 in RASFs led to decreased levels of CYR-61 and deacetylation of FoxO3a. Following treatment with simvastatin, the expression of SIRT-1 was up-regulated and SIRT-1/FoxO3a binding was enhanced in RASFs. In rats with CIA, intraarticular injection of simvastatin alleviated arthritis and suppressed CYR-61 expression and FoxO3a phosphorylation in synovial fibroblasts. CONCLUSION: CYR-61 is important in the pathogenesis of RA, and SIRT-1/FoxO3a signaling is crucial to induction of CYR-61 in RASFs. Simvastatin plays a beneficial role in inflammatory arthritis through its up-regulation of SIRT-1/FoxO3a signaling in synovial fibroblasts. Continued study of the pathways linking sirtuins, FoxO proteins, and the inflammatory responses of RASFs may provide new insights into the pathophysiology of RA.

Needlestick and sharps injuries among dental healthcare workers at a university hospital.

BACKGROUND/PURPOSE: Needlestick/sharps injuries (NSI) are a major occupational hazard among healthcare workers. Since needles and sharps are commonly used during dental procedures, workers in the dental profession are especially prone to sharps-related injuries. In this study, NSI among workers in the dental department of National Taiwan University Hospital (NTUH) were analyzed to find out the risk factors associated with NSI. METHODS: NSI cases reported by the Department of Dentistry to NTUH from 2009 to 2011 were collected. Correlations between NSI and parameters related to the events were analyzed. RESULTS: A total of 56 NSI events including 31 occurring during surgical treatment and 25 occurring during cleanup procedure were reported. The annual incidence of NSI was 8.19% among all dental workers. NSI incidences per person-year were 21.28% for interns, 7.50% for residents, 6.77% for nursing staffs, 3.33% for clerks, and 0.85% for attending doctors (P < 0.001, chi-square test). NSI events occurred more frequently in the 3-month period from July to September (20 cases), on Wednesday (18 cases) or Friday (14 cases), and at the hours from 11:00 to 14:00 and after 16:00 (39 cases). Dental injection needle (19 cases) was the most common instrument involved in NSI and 9 of these 19 needle injuries occurred during need removal. CONCLUSION: NSI events tend to occur in dental personnel (interns) with lesser clinical skill and experience, in the period (from July to September) when new interns and residents join the clinic, on the working days in the middle (Wednesday) and end (Friday) of the week, and at the hours close to lunch break (11:00 to 14:00) and getting off duty (after 16:00). In addition, establishment of standard operating procedure for injection needle removal is necessary, because one-third of NSI are needle-related.

Expression of Gα12 predicts progression and prognosis of oral squamous cell carcinomas in Taiwan.

BACKGROUND: Expression of Gα12 is found to be associated with cancer cell proliferation, migration, invasion, and metastasis. METHODS: This study used immunohistochemistry to examine the expression of Gα12 protein in 100 specimens of oral squamous cell carcinoma (OSCC), 45 specimens of oral epithelial dysplasia (OED), and 36 specimens of normal oral mucosa (NOM). RESULTS: The mean Gα12 labeling indices (LIs, defined as the percentage of positive cells in total cells) increased significantly from NOM (7 ± 11%) through OED (21 ± 20%) to OSCC samples (53 ± 33%, P < 0.001). The higher mean Gα12 LI was significantly associated with OSCCs with larger tumor size (P = 0.003), positive lymph node metastasis (P = 0.002), or more advanced clinical stages (P = 0.003). Positive lymph node metastasis (P = 0.039) and Gα12 LI > 50% (P = 0.009) were identified as independent unfavorable prognosis factors by multivariate analyses with Cox regression model. Moreover, Kaplan-Meier curve showed that OSCC patients with a Gα12 LI > 50% had a significantly poorer cumulative survival than those with a Gα12 LI ≤ 50% (log-rank test, P = 0.009). CONCLUSIONS: Our results showed a stepwise and significant elevation in Gα12 protein expression from NOM through OED to OSCCs, suggesting that overexpression of Gα12 protein may be an early event in oral carcinogenesis and may play a pivotal role in oral cancer development. Moreover, the Gα12 protein can be a biomarker for prediction of the progression of OSCCs and the prognosis of patients with OSCC in Taiwan.

Transverse and sagittal angulations of proximal segment after sagittal split and vertical ramus osteotomies and their influence on the stability of distal segment.

BACKGROUND/PURPOSE: This study aimed at comparing the transverse and sagittal angulations of proximal segment after sagittal split ramus osteotomy (SSRO) and intraoral vertical ramus osteotomy (IVRO), and examining their influences on the stability of distal segment. METHODS: Patients who received SSRO (n = 21) or IVRO (n = 11) for mandibular setback were included. Lateral and posteroanterior cephalograms taken within 1 month before surgery (T1), within 1 week after surgery (T2), and at least 6 months after surgery (T3) were analyzed. The angulation of each proximal segment relative to the upper orbital margin line was measured on posteroanterior cephalogram and the sum of both angles (total ramus angle, TRA) was obtained. On lateral radiograph, ramus inclination angle (RIA) relative to a horizontal reference line 7° to the sella-nasion was assessed and B-point position was measured. RESULTS: From T1 to T2, more increases in TRA and RIA were noted after IVRO than after SSRO. From T2 to T3, TRA and RIA significantly decreased in IVRO group but remained relatively stable in SSRO group. ΔTRA(T1-T2) positively related to upward rotation of distal segment for SSRO and downward rotation for IVRO from T2 to T3. For SSRO only, ΔRIA(T1-T2) significantly related to forward movement of distal segment during remodeling. CONCLUSION: TRA and RIA increase significantly after IVRO and then regress, whereas they increase mildly after SSRO and remain stable. Increase in TRA significantly relates to distal segment rotation during remodeling for both surgeries, but increase in RIA relates to forward relapse of the distal segment only for SSRO. The reasons underlying the correlations are not certain and deserve future investigations.

Increased placenta growth factor mRNA level is significantly associated with progression, recurrence and poor prognosis of oral squamous cell carcinoma.

BACKGROUND/PURPOSE: Expression of placenta growth factor (PlGF) mRNA is shown to correlate with the progression and prognosis of several human cancers. In this study, we assessed whether the PlGF mRNA level in oral squamous cell carcinoma (OSCC) tissue could be used to predict the progression and prognosis of OSCCs in Taiwan. METHODS: This study used quantitative real-time reverse transcription-polymerase chain reaction (quantitative RT-PCR) to detect the PlGF mRNA levels in 63 paired OSCC and adjacent normal-looking oral mucosa (non-OSCC) tissues. Threshold cycle (CT) was defined as the PCR cycle number needed to generate a pre-determined amount of DNA (threshold). For a chosen threshold, a smaller starting copy number of mRNA results in a higher CT value. In this study, the relative expression level of tissue PlGF mRNA in each OSCC patients was expressed as -ΔCT = -(OSCC CT - non-OSCC CT). Thus, the higher the -ΔCT, the greater the copy number of PlGF mRNA in tissues. RESULTS: We found that the higher mean PlGF mRNA -ΔCT value was significantly associated with OSCCs with larger tumor size (p = 0.03), positive lymph node metastasis (p = 0.003), more advanced clinical stages (p = 0.013) or the presence of loco-regional recurrence (p = 0.039). Positive lymph node metastasis (p = 0.019) and PlGF mRNA -ΔCT value >2 (p = 0.016) were identified as two independent unfavorable prognosis factors by multivariate analyses with Cox regression model. Moreover, Kaplan-Meier curve showed that OSCC patients with a PlGF mRNA -ΔCT value >2 had a significantly poorer recurrence-free survival than those with a PlGF mRNA -ΔCT value ≤2 (log-rank test, p = 0.017). CONCLUSION: The OSCC tissue PlGF mRNA level can be used to predict the progression and prognosis of OSCCs in Taiwan.

Metformin Reduces Bone Resorption in Apical Periodontitis Through Regulation of Osteoblast and Osteoclast Differentiation.

INTRODUCTION: We have previously demonstrated that auxiliary metformin therapy promotes healing of apical periodontitis. Here we aimed to investigate the effects of metformin on osteoblast differentiation and osteoclast formation in cultured cells and rat apical periodontitis. METHODS: Murine pre-osteoblasts MC3T3-E1 and macrophages RAW264.7 were cultured under hypoxia (2% oxygen) or normoxia (21% oxygen) and stimulated with receptor activator of nuclear factor-κB ligand (RANKL) when indicated. Metformin was added to the cultures to evaluate its anti-hypoxic effects. Expressions of osteoblast differentiation regulator runt-related transcription factor 2 (RUNX2), RANKL, and osteoclast marker tartrate-resistant acid phosphatase (TRAP) were assessed by Western blot. Apical periodontitis was induced in mandibular first molars of 10 Sprague-Dawley rats. Root canal therapy with or without metformin supplement was performed. Periapical bone resorption was measured by micro-computed tomography. Immunohistochemistry was used to examine RUNX2, RANKL, and TRAP expressions. RESULTS: Hypoxia suppressed RUNX2 expression and enhanced RANKL synthesis in pre-osteoblasts. TRAP production increased in macrophages after hypoxia and/or RANKL stimulation. Metformin reversed hypoxia-induced RUNX2 suppression and RANKL synthesis in pre-osteoblasts. Metformin also inhibited hypoxia and RANKL-enhanced TRAP synthesis in macrophages. Intracanal metformin diminished bone loss in rat apical periodontitis. Comparing with vehicle control, cells lining bone surfaces in metformin-treated lesions had significantly stronger expression of RUNX2 and decreased synthesis of RANKL and TRAP. CONCLUSIONS: Alleviation of bone resorption by intracanal metformin was associated with enhanced osteoblast differentiation and diminished osteoclast formation in rat apical periodontitis. Our results endorsed the role of metformin as an effective medicament for inflammatory bone diseases.

Epigallocatechin-3-gallate diminishes cytokine-stimulated Cyr61 expression in human osteoblastic cells: a therapeutic potential for arthritis.

OBJECTIVE: To assess the effects of epigallocatechin-3-gallate (EGCG) on cytokine-induced Cyr61 synthesis in human osteoblastic cells and the associated signalling pathways. The therapeutic effect of EGCG on CIA in rats was also studied. METHODS: The expression of Cyr61 and NF-κB pathway molecules was examined by western blotting. CCL2 expression was assessed by northern blotting and ELISA. Interaction between NF-κB and Cyr61 promoter was evaluated by electrophoretic mobility shift assay. In rat CIA, osteoblastic expression of Cyr61 was examined by immunohistochemistry and disease progression was assessed by clinical, radiographic and histological examinations. RESULTS: EGCG inhibited Cyr61 expression stimulated by cytokines in primary human osteoblasts and human osteoblastic cell line U2OS. In U2OS, oncostatin M (OSM) induced IκB-α degradation through the mTOR/rictor/Akt pathway, and EGCG attenuated the action. Electrophoretic mobility shift assay revealed that the OSM-enhanced NF-κB/DNA binding was reduced by EGCG, possibly through abrogating nucleus localization of p65 and p50. Cyr61 enhanced OSM-induced expression of CCL2. Moreover, EGCG diminished OSM-stimulated CCL2 expression at least partially via suppressing Cyr61 induction. Co-distribution of CD68(+) macrophages and Cyr61(+) osteoblasts in osteolytic areas was obvious in the CIA model. Clinical, radiographic and immunohistochemical analyses revealed that administration of EGCG markedly diminished the severity of CIA, macrophage infiltration, and the number of Cyr61-synthesizing osteoblasts. CONCLUSION: By modulating the mTOR/rictor/Akt/NF-κB pathway, EGCG attenuated Cyr61 production in osteoblastic cells and in turn diminished macrophage chemotaxis. Our data support the therapeutic potential of EGCG on arthritis.

Simvastatin inhibits cytokine-stimulated Cyr61 expression in osteoblastic cells: a therapeutic benefit for arthritis.

OBJECTIVE: To examine the effects of proinflammatory cytokines on Cyr61 expression in osteoblastic cells and the modulatory action of simvastatin, to assess the role of CREB in Cyr61 induction, and to investigate the relationship of osteoblastic expression of Cyr61 to disease progression in experimental arthritis. METHODS: Cyr61 expression and CREB phosphorylation at serine 133 were examined by Western blotting. Promoter activity of Cyr61 was assessed by luciferase assay with promoter deletion/mutagenesis and forced expression/gene silencing of CREB. Interaction between CREB and the Cyr61 promoter was evaluated by electrophoretic mobility shift assay and chromatin immunoprecipitation. CCL2 expression was examined by Northern blotting and enzyme-linked immunosorbent assay. In rats with collagen-induced arthritis (CIA), osteoblastic expression of Cyr61 was examined by immunohistochemistry, and disease progression was assessed by clinical, radiographic, and histologic examination. RESULTS: In primary human osteoblasts and U2OS cells, Cyr61 expression stimulated by tumor necrosis factor α, interleukin-1ß (IL-1ß), oncostatin M (OSM), and other IL-6-family cytokines was suppressed by simvastatin. In U2OS cells, simvastatin inhibited OSM-induced CREB phosphorylation and CREB-DNA binding. Knockdown of CREB by short hairpin RNA reduced Cyr61 synthesis. OSM-induced Cyr61 promoter activation was dependent on CRE-CREB interaction and inhibited by simvastatin. Cyr61 enhanced CCL2 expression by U2OS cells. Intraarticular injection of simvastatin inhibited CIA progression and diminished the number of Cyr61+ osteoblasts and infiltrating macrophages. CONCLUSION: Simvastatin inhibited cytokine-stimulated Cyr61 expression in osteoblastic cells and suppressed disease progression and osteoblastic expression of Cyr61 in inflammatory arthritis. This finding indicates that simvastatin may have potential as a therapeutic agent for inflammatory arthritis.

Effects of Interleukin-6 on STAT3-regulated signaling in oral cancer and as a prognosticator of patient survival.

OBJECTIVES: Human oral squamous cell carcinoma (OSCC) produces an inflammatory microenvironment enriched with cytokines including interleukin-6 (IL-6); however, the underlying molecular mechanisms of OSCC progression are unclear. We aimed to delineate the STAT3-mediated signaling pathways involved in tumor cell survival and growth. MATERIALS AND METHODS: Immunohistochemistry was used to semi-quantitate IL-6 and STAT3 in 111 OSCC tissues. IL-6-induced STAT3 signaling pathways and effects on tumor cell survival and progression were investigated in vitro and in xenograft mouse models. Effects of blocking IL-6-induced activation of STAT3 in an OSCC cell line were determined in vitro. RESULTS: A higher level of IL-6 or STAT3 in situ was associated with an unfavorable prognosis in OSCC patients with regard to both disease-free and overall survival rates. Overexpressed or exogenous IL-6 could induce SAS cell proliferationin vitroand significantly enhanced tumor growthin vivo. In addition, knockdown or inhibition of STAT3 expression in SAS cells significantly reduced tumor growth and abolished the responsiveness to IL-6 stimulation. Siltuximab or Tocilizumab could also significantly suppress IL-6-induced STAT3 phosphorylation and STAT3 nuclear translocation, resulting in a significant decrease of downstream anti-apoptotic proteins Bcl-2, Bcl-xL, and survivin. CONCLUSION: The IL-6 level in the tumor microenvironment could serve as a stage-independent predictor of OSCC progression and survival. Further, IL-6 may play a role in this disease through STAT3-dependent upregulation of anti-apoptotic genes and subsequent proliferation of tumor cells.

Expression of vascular endothelial growth factor is significantly associated with progression and prognosis of oral squamous cell carcinomas in Taiwan.

BACKGROUND/PURPOSE: Expression of vascular endothelial growth factor (VEGF) correlates with progression and prognosis of several human cancers. The main purposes of this study were to assess expression of VEGF in specimens of oral squamous cell carcinoma (OSCC) and to evaluate the possible influence of VEGF on the progression and prognosis of OSCC in Taiwan. METHODS: An immunohistochemical technique was used to examine the expression of VEGF in 100 specimens of OSCC, 66 specimens of oral epithelial dysplasia, and 36 specimens of normal oral mucosa. RESULTS: We found that the mean labeling indices (Lis) of VEGF increased significantly from normal oral mucosa (13 ± 6%), through mild (22 ± 8%), moderate (24 ± 13%), and severe oral epithelial dysplasia (32 ± 14%), to OSCC samples (50 ± 18%, p < 0.001). The higher mean VEGF LI was significantly related to OSCC with positive lymph node metastasis (p = 0.022) and with more advanced clinical stages (p = 0.046). In addition, positive lymph node metastasis (p = 0.008) and VEGF LI > 40% (p = 0.046) were identified as independent unfavorable prognosis factors for OSCC patients by multivariate analysis with the Cox regression model. Moreover, the Kaplan-Meier curve showed that OSCC patients with a VEGF LI > 40% had a significantly poorer cumulative survival than those with a VEGF LI ≤ 40% (log-rank test, p = 0.016). CONCLUSION: We conclude that VEGF may be a biomarker for prediction of the progression and prognosis of OSCC in Taiwan.

Differential toxicities of intraneurally injected mercuric chloride for sympathetic and somatic motor fibers: an ultrastructural study.

BACKGROUND/PURPOSE: Mercury is a well-known neurotoxin but the susceptibility of autonomic nerves to mercury poisoning in vivo has seldom been studied. Our previous studies have shown that the hypoglossal nerve in hamsters contains somatic motor and postganglionic sympathetic fibers. The aim of this study was to investigate the ultrastructural changes in the nervous system following intraneural injection of mercuric chloride into the hypoglossal nerve in hamsters. METHODS: Six adult hamsters were used in this study. After anesthesia, the digastric muscle on the right side was removed and the trunk of the hypoglossal nerve was exposed. Two microliters of mercuric chloride aqueous solution was injected into the main trunk of the hypoglossal nerve at the bifurcation. The contralateral hypoglossal nerve was kept intact and used as the normal control. Animals were allowed to survive for 1 or 3 days and were prepared for ammonium sulfide histochemistry and electron microscopy. RESULTS: Three days after injection of mercuric chloride solution, almost all unmyelinated sympathetic fibers in the hypoglossal nerve trunk were lost, whereas myelinated somatic axons were spared. Although mercury deposition in the myelin sheaths of neuronal processes was observed in the hypoglossal nucleus, the neuronal somas were intact. By contrast, degenerated neuronal processes and mercury deposition in neuronal somas were frequently found in the superior cervical ganglia. CONCLUSION: This study demonstrated an undue susceptibility of sympathetic fibers to mercury intoxication. The mechanisms that underlie the selective reaction of sympathetic fibers to mercury warrant further investigation.