Miyako Kurihara

Downregulation of miR-126 induces angiogenesis and lymphangiogenesis by activation of VEGF-A in oral cancer

Background:MicroRNA (miRNA)-126 (miR-126) is an endothelial-specific miRNA located within intron 7 of epidermal growth factor-like domain 7 (EGFL7). However, the role of miR-126 in cancer is controversial.Methods:We examined the function of miR-126 in oral squamous cell carcinoma (OSCC) cells. Furthermore, a series of 118 cases with OSCC were evaluated for the expression levels of miR-126.Results:MicroRNA-126 (miR-126) was associated with cell growth and regulation of vascular endothelial growth factor-A activity, and demethylation treatment increased expression levels of miR-126 and EGFL7 in OSCC cells. A significant association was found between miR-126 expression and tumour progression, nodal metastasis, vessel density, or poor prognosis in OSCC cases. In the multivariate analysis, decreased miR-126 expression was strongly correlated with disease-free survival.Conclusion:The present results suggest that miR-126 might be a useful diagnostic and therapeutic target in OSCC.

MIA-dependent angiogenesis and lymphangiogenesis are closely associated with progression, nodal metastasis and poor prognosis in tongue squamous cell carcinoma.

We examined the role of angiogenesis/lymphangiogenesis and the relationship between melanoma inhibitory activity (MIA) and angiogenesis or lymphangiogenesis in oral squamous cell carcinoma (OSCC). One hundred and one formalin-fixed, paraffin-embedded specimens of primary OSCC were evaluated for microvessel density (MVD), lymphovessel density (LVD), expression of vascular endothelial growth factor (VEGF), VEGF-C, VEGF-D and MIA. Fresh frozen 18 samples of primary OSCC were further examined for the expression of VEGF, VEGF-C, VEGF-D and MIA protein by enzyme-linked immunosorbent assay (ELISA). In in vitro analysis, we studied the change of VEGF, VEGF-C and VEGF-D expression after MIA siRNA treatment. Higher MVD, LVD and VEGF expression levels were closely associated with tumour progression, nodal metastasis and poor prognosis. Expression levels of VEGF-C and VEGF-D were only related with nodal metastasis. MIA expression was significantly associated with MVD, LVD, VEGF, VEGF-C and VEGF-D expression by immunohistochemistry and ELISA assay. VEGF, VEGF-C, VEGF-D and MIA expression levels of metastatic tongue cancer HSC-3 cells were higher than those with no metastatic HSC-4 cells, and VEGF, VEGF-C and VEGF-D expression levels were decreased by MIA siRNA treatment in both cells. MIA-dependent angiogenesis/lymphangiogenesis might be a useful therapeutic target in progressive and metastatic OSCC.

Maxillofacial Fractures Resulting From Falls

PURPOSE The purpose of this study was to analyze maxillofacial fractures resulting from falls in terms of the demographics, the circumstance of injury, the site and severity of fracture, and the treatment. PATIENTS AND METHODS Data of 457 patients treated for fall-related maxillofacial fractures at the Department of Oral and Maxillofacial Surgery, Nara Medical University, Nara, Japan, from 1981 to 2007 were retrospectively analyzed. RESULTS Patients were 163 males and 116 females with an average age of 51.3 years who had fallen on a level surface (simple fall), and 110 males and 68 females with an average age of 31.9 years in falls from a greater height (fall from height), respectively. Fractures of the mandible were more frequently observed than those of the midface. In the mandible, fracture lines were exclusively observed at the condyle, especially in simple falls. In the midface, the zygoma was most frequently involved. Facial Injury Severity Scale ranged from 1 to 6, with an average of 1.78 in simple falls, and from 1 to 9, with an average of 2.04 in falls from height, respectively. These were dependent on the causes and height of the fall. Fractures at the other sites of the body were found in 14 patients (5.0%) with simple falls and 38 (21.3%) with falls from height. Maxillomandibular fixation was most frequently chosen for mandibular fractures and observation for midface fractures. Open reduction and fixation was more frequently chosen in patients with falls from height than those with simple falls and in patients with a higher Facial Injury Severity Scale score. CONCLUSIONS Maxillofacial fractures resulting from falls showed characteristic features in the demographics, the circumstance of injury, and the site and severity of fracture. Treatment was chosen according to these features.

Prox1 and FOXC2 Act as Regulators of Lymphangiogenesis and Angiogenesis in Oral Squamous Cell Carcinoma

Prospero homeobox 1 (Prox1) and forkhead box (FOX) C2 regulate angiogenesis and/or lymphangiogenesis. However, the detailed role and function of Prox1 and FOXC2 in cancer remains controversial. In the present study, we examined the expression of Prox1 and FOXC2 proteins in specimens from 163 cases with oral squamous cell carcinoma (OSCC). Furthermore, the role of Prox1 and FOXC2 in cancer cell growth and invasion was evaluated in cultured OSCC cells. Prox1 expression was significantly associated with local progression of the tumor (P = 0.0023), clinical stage (P<0.0001), lymphovessel density (LVD) (P<0.0001), nodal metastasis (P<0.0001), and worse prognosis (P<0.0001). Immunoreactivity of FOXC2 was strongly correlated with microvessel density (MVD) (P<0.0001) and poor prognosis (P = 0.0076). In vitro analysis demonstrated that Prox1 regulates cell growth, proliferation, invasion, and lymphangiogenesis by activating vascular endothelial growth factor (VEGF)-C expression. Furthermore, FOXC2 enhanced the expression level of Prox1 and promoted angiogenesis by enhancement of VEGF-A expression. Our results suggested that Prox1 and FOXC2 play key roles in OSCC progression and that further studies focusing on these proteins may yield useful insights for diagnosis and therapy of OSCC.

Tropomyosin receptor kinases B and C are tumor progressive and metastatic marker in colorectal carcinoma

Members of the tropomyosin receptor kinase (Trk) family have a high affinity for neurotrophins and regulate neuronal survival. The role of Trks in cancer is still controversial. The expression and role of TrkB and TrkC were examined in colorectal cancer (CRC). Immunohistochemical analysis of TrkB and TrkC was performed in 133 patients with CRC. Using human CRC cell lines, expression of vascular endothelial growth factor (VEGF) and transforming growth factor β, cell growth, invasion, and apoptosis were examined by knockdown methods. Immunohistochemistry showed positive results of TrkB and TrkC (23.3% and 12.8%, respectively). TrkB expression was associated with local progression (P = .0284), clinical stage (P = .0026), nodal metastasis (P = .0068), and peritoneal metastasis (P = .0026). TrkC expression was only related to liver metastasis (P = .0001). Coexpression of TrkB or TrkC and their ligands was found in 80.6% and 82.4% of cases, respectively. In vitro analysis using human CRC cells showed that TrkB positively regulated gene expression of VEGF-A (P < .05) and VEGF-C (P < .05), whereas TrkC suppressed transforming growth factor β expression (P < .05). TrkB and TrkC induced cell growth (P < .05) and invasion (P < .05), respectively. Both TrkB and TrkC showed antiapoptotic effect (P < .05). These results suggest that TrkB and TrkC have a tumor progressive function and may be a useful diagnostic and therapeutic target in CRC.

HMGB1 attenuates anti-metastatic defence of the liver in colorectal cancer

High mobility group box (HMGB) 1 induces apoptosis of monocyte-lineage cells. We examined the effect of HMGB1 on Kupffer cells (KCs). In 50 Dukes C and 12 liver-metastasised Dukes D colorectal cancers (CRCs), higher HMGB1 concentration in the primary tumours and metastatic foci, and fewer KCs were found in Dukes D cases than in Dukes C cases. The portal blood HMGB1 concentration was higher in Dukes D cases than in Dukes C cases. HMGB1 induced growth inhibition and apoptosis in mouse KCs in a dose-dependent manner, which was associated with the phosphorylation of c-Jun N-terminal kinase (JNK). JNK inhibition and knockdown of HMGB1 receptor abrogated growth inhibition and apoptosis. In a nude mouse liver metastasis model, the caecal administration of HMGB1 decreased the number of KCs and increased the embedment of Colo320 CRC cells in a dose-dependent manner. HMGB1 transfection increased the liver metastasis of Colo320 cells, and the metastasis was inhibited by anti-HMGB1 antibody administration. These results suggest that HMGB1 secreted from primary tumours decreases the number of KCs and attenuates the anti-metastatic defence of the liver in patients with CRCs.

Protumoral roles of melanoma inhibitory activity 2 in oral squamous cell carcinoma

Background:The role of melanoma inhibitory activity 2 (MIA2) was examined in human oral squamous cell carcinoma (OSCC).Methods:MIA2 role was examined by immunohistochemistry of human OSCCs and knockdown studies using human 3 OSCC cell lines with MIA2 expression.Results:MIA2 expression was observed in 62 (66.7%) of 93 OSCCs and was associated with tumour expansion and nodal metastasis. Melanoma inhibitory activity 2 expression was inversely correlated with intratumoral infiltration of lymphocytes. Invasion and anti-apoptotic survival were reduced by MIA2 knockdown in HSC3 cells. MOLT-3 lymphocytes infiltrating the HSC3 cell layer was enhanced by MIA2 knockdown or MIA2 depletion with the antibody. In HSC3 cells, MIA2 knockdown decreased the expressions of vascular endothelial growth factor (VEGF), VEGF-C, and VEGF-D. The downregulation of VEGF-C and -D was caused by inhibition of p38 and extracellular signal-regulated kinase (ERK)1/2, respectively. Melanoma inhibitory activity 2 was co-precipitated with integrin α4 andα5 in HSC3 cells. Integrin α4 knockdown decreased p38 phosphorylation and increased apoptosis, whereas integrin α5 knockdown decreased c-Jun N-terminal kinase (JNK) phosphorylation and apoptosis. Inhibition of JNK decreased apoptosis in the HSC3 cells.Conclusion:These findings suggest that the roles of MIA2 might be based on the variety of the integrins and the subtypes of mitogen-activated protein kinase.

Trks are novel oncogenes involved in the induction of neovascularization, tumor progression, and nodal metastasis in oral squamous cell carcinoma

The function of tropomyosin receptor kinase (Trk) family including TrkA, TrkB, and TrkC in cancer remains unknown. The role of Trks in oral squamous cell carcinoma (OSCC) was examined. Knockdown of Trks provided inhibition of growth or invasion and decrease of apoptosis in OSCC cells, which expressed Trks at high levels. VEGF expression was associated with TrkA and TrkB expression; a decrease of VEGF-C and VEGF-D was observed in OSCC cells with TrkB knockdown. TrkC did not affect the expression of VEGF family. An immunohistochemical analysis of 102 OSCCs showed that TrkB expression was related to microvessel density (MVD), lymph vessel density (LVD), and poor prognosis. TrkC expression was correlated with clinical stage, lymph node metastasis, MVD, LVD, and poor prognosis. TrkA expression was associated with VEGF expression, whereas TrkB expression was associated with the expressions of VEGF, VEGF-C and VEGF-D. No significant association was found between the expression of TrkC and genes of the VEGF family. Expression of Trks was not associated with RUNX3 silencing by methylation in OSCC cells. Trks expression was inversely correlated with RUNX3 expression in the OSCC cases. These results suggested that Trks enhances progression of OSCC through angiogenesis and lymphangiogenesis.

Transport and Golgi organisation protein 1 is a novel tumour progressive factor in oral squamous cell carcinoma.

Transport and Golgi organisation protein 1 (TANGO), also known as MIA3, belongs to the melanoma inhibitory activity (MIA) gene family. Although MIA acts as an oncogene, MIA2 and TANGO have a tumour-suppressive function in several malignancies; accordingly, the role and function of the MIA gene family in tumours remain controversial. Here the roles of TANGO were investigated in oral squamous cell carcinoma (OSCC). We analysed expression and function of TANGO in human OSCC cell lines. TANGO expression was also examined in 171 cases of primary OSCC by immunohistochemistry and statistically assessed the correlation between TANGO positivity and the clinicopathological parameters including vessel density. By TANGO knockdown in OSCC cells, the growth and invasion were repressed and apoptosis was induced. Activities of platelet-derived growth factor beta polypeptide (PDGFB) and Neuropilin2 were inhibited by TANGO knockdown. TANGO immunoreactivity was detected in 35.1% (60/171) cases of OSCC. TANGO expression was strongly associated with tumour progression, nodal metastasis, clinical stage and number of blood or lymph vessels in OSCC. Patients showing TANGO-expression fared significantly worse disease-free survival than cases without TANGO expression. These findings suggest that TANGO might promote angiogenesis and lymphangiogenesis by upregulation of PDGFB and Neuropilin2 in OSCC.

Whole saliva flow rate and body profile in healthy young adults.

OBJECTIVE The purpose of this study was to clarify the effect of the body profile on the whole saliva flow rate in healthy male and female subjects. STUDY DESIGN The whole saliva flow rate was evaluated under unstimulated (UWSFR) and stimulated conditions by the gum test (SWSFR-GT) and Saxon test (SWSFR-ST), and its correlation with body profiles such as body height (BH), body weight (BW), body surface area (BSA) and body mass index (BMI) was analysed in 100 male and 100 female subjects. RESULTS The averages of UWSFR, SWSFR-GT and SWSFR-ST and those of BH, BW, BSA and BMI were significantly larger in males than in females (p<0.0001). No correlation was observed between any of UWSFR, SWSFR-GT and SWSFR-ST and any of BH, BW, BSA and BMI for either males or females. However, UWSFR, SWSFR-GT and SWSFR-ST were significantly correlated with BH, BW and BSA when data from male and female subjects were combined. CONCLUSION The whole saliva flow rate from an individual should only be compared with the data from the group of the same gender.