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Medication-related osteonecrosis of jaws (MRONJ) is one of the most complicated inflammatory conditions in oral and maxillofacial region. It is very difficult to correctly evaluate the degree and extent of necrosis and infection. This refractory osteonecrosis often needs extended surgery, leading to impaired quality-of-life. We have performed hyperbaric oxygen therapy (HBO) combined with conservative surgery for advanced cases. We have appraised the value of FDG-PET and 3-phase bone scintigraphy in the diagnosis and management of this condition. MRONJ showed significantly higher SUV max on FDG-PET than the others. Although the 3 phase pool bone images did not change significantly, perfusion and static bone image as well as PET showed remarkable response to HBO for MRONJ. SUV max after HBO was significantly lower than those of before HBO. These preliminary results indicate that FDG-PET is useful for monitoring the effect of HBO for MRONJ.

Objective: Hypoxia is a common feature and prognostic factor in cancer. 18 F-fluoromisonidazole (FMISO) positron emission tomography (PET) can detect tumor hypoxia noninvasively. The aim of this study was to assess the correlations between FMISO-PET and 18 F-fluorodexyglucose (FDG)-PET parameters with cell proliferation and hypoxia in patients with oral squamous cell carcinoma (OSCC)., Study Design: Twenty-three preoperative patients with OSCC were included. The tumor/muscle ratio (TMR) of FMISO-PET, the maximum standardized uptake values (SUV max ) of FDG-PET, metabolic tumor volume, and total lesion glycolysis were measured. Ki-67 and hypoxia-inducible factor-1α (HIF-1α) expression was immunohistochemically evaluated., Results: FMISO TMR (P = .003) and FDG SUV max (P = .04) were significantly higher in patients with high expression of Ki-67 compared with those with low expression of Ki-67. FMISO TMR (P = .006) and FDG SUV max (P = .01) were also significantly higher in patients with HIF-1α expression than in those without HIF-1α expression. Metabolic tumor volume was not significantly related to either Ki-67 or HIF-1α expression. Multivariate analysis showed that FMISO TMR was independently predictive of Ki-67 (P = .002; odds ratio 31.1) and HIF-1α (P = .049; odds ratio 10.5) expression., Conclusions: FMISO-PET showed significant relationships with Ki-67 and HIF-1α expression, which are key features of cell proliferation and hypoxia in OSCC., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Objective: Sequential postoperative salivary interleukin-6 (IL-6) concentrations were examined in patients with oral squamous cell carcinoma (OSCC) who had early or late locoregional recurrences or those who did not., Study Design: Twenty-seven consecutive patients with OSCC were originally included in the study. All patients underwent radical surgery. Four saliva samples were collected before (periods I and II) and after (periods III and IV) surgery, and IL-6 concentrations were measured., Results: Although postoperative (period III: at the time of discharge) salivary IL-6 level was significantly higher in patients with early locoregional recurrence (P = .02) than in those without, no such relationships were observed for preoperative IL-6 concentrations (periods I and II). Postoperative (period IV: 24 months after surgery) IL-6 level was significantly higher in patients with late locoregional recurrence (P = .03) than in those without, but no such relationships were observed for IL-6 concentrations in periods I, II, and III., Conclusions: Sequential postoperative salivary IL-6 concentration may be a useful marker for diagnosis of early and late locoregional recurrence in OSCC., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Tumor angiogenesis plays an important role in tumor progression and metastasis. Tumor endothelial cells (TECs) are a therapeutic target of antiangiogenic chemotherapy that was recently developed and is currently being investigated in the clinic with promising results. Low-dose chemotherapy, which is the long-term administration of relatively low doses of chemotherapeutic agents, has been proposed for targeting tumor angiogenesis in various types of cancers. Although the efficacy of low-dose chemotherapy has been confirmed in several clinical models, some studies show insufficient therapeutic effect for malignant cancers. As a possible mechanism of the treatment failure, it has been considered that tumor cells may acquire resistance to this therapy. However, drug resistance by TECs may also be due to another mechanism for resistance of tumor cells to low-dose chemotherapy. We reported elsewhere that TECs were resistant to the anticancer drug paclitaxel, which is a mitotic inhibitor, concomitant with P-glycoprotein up-regulation. Verapamil, a P-glycoprotein inhibitor, abrogated TEC resistance in vitro. Herein, we demonstrated that verapamil coadministration enhanced the effects of low-dose paclitaxel concomitant with inhibiting tumor angiogenesis in a preclinical in vivo mouse melanoma xenograft model. Furthermore, verapamil coadministration reduced lung metastasis. These results suggest that inhibiting P-glycoprotein in TECs may be a novel strategy for low-dose chemotherapy targeting TECs., (Copyright © 2015 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Dysfunctional sinusoidal liver endothelial cells (LECs) are associated with liver diseases, such as liver fibrosis, cirrhosis, and portal hypertension. Because of this, gene therapy targeted to LECs would be a useful and productive strategy for directly treating these diseases at the level of genes. Here, we report on the development of a transgene vector that specifically targets LECs. The vector is a liposome-based gene vector coated with hyaluronic acid (HA). HA is a natural ligand for LECs and confers desirable properties on particles, rendering them biodegradable, biocompatible, and nonimmunogenic. In this study, we constructed HA-modified carriers, and evaluated cellular uptake and transfection activity using cultured LECs from KSN nude mice (KSN-LECs). Cellular uptake analyses showed that KSN-LECs recognized the HA-modified carriers more effectively than skin endothelial cells. The transfection assay indicated that the efficient gene expression in KSN-LECs, using the HA-modified carriers, required an adequate lipid composition and a functional device to control intracellular trafficking. This finding contributes to our overall knowledge of transgene expression targeted to LECs., (Copyright © 2013 Wiley Periodicals, Inc.)

An important concept in tumor angiogenesis is that tumor endothelial cells (TECs) are genetically normal and homogeneous. However, we previously reported that TECs differ from normal ECs. Whether the characteristics of TECs derived from different tumors differ remains unknown. To elucidate this, in this study, we isolated two types of TECs from high-metastatic (HM) and low-metastatic (LM) tumors and compared their characteristics. HM tumor-derived TECs (HM-TECs) showed higher proliferative activity and invasive activity than LM tumor-derived TECs (LM-TECs). Moreover, the mRNA expression levels of pro-angiogenic genes, such as vascular endothelial growth factor (VEGF) receptors 1 and 2, VEGF, and hypoxia-inducible factor-1α, were higher in HM-TECs than in LM-TECs. The tumor blood vessels themselves and the surrounding area in HM tumors were exposed to hypoxia. Furthermore, HM-TECs showed higher mRNA expression levels of the stemness-related gene stem cell antigen and the mesenchymal marker CD90 compared with LM-TECs. HM-TECs were spheroid, with a smoother surface and higher circularity in the stem cell spheroid assay. HM-TECs differentiated into osteogenic cells, expressing activated alkaline phosphatase in an osteogenic medium at a higher rate than either LM-TECs or normal ECs. Furthermore, HM-TECs contained more aneuploid cells than LM-TECs. These results indicate that TECs from HM tumors have a more pro-angiogenic phenotype than those from LM tumors., (Copyright © 2012 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Tumor endothelial cells (TECs) are therapeutic targets in anti-angiogenic therapy. Contrary to the traditional assumption, TECs can be genetically abnormal and might also acquire drug resistance. In this study, mouse TECs and normal ECs were isolated to investigate the drug resistance of TECs and the mechanism by which it is acquired. TECs were more resistant to paclitaxel with the up-regulation of multidrug resistance (MDR) 1 mRNA, which encodes the P-glycoprotein, compared with normal ECs. Normal human microvascular ECs were cultured in tumor-conditioned medium (CM) and became more resistant to paclitaxel through MDR1 mRNA up-regulation and nuclear translocation of Y-box-binding protein 1, which is an MDR1 transcription factor. Vascular endothelial growth factor (VEGF) receptor 2 (VEGFR2) and Akt were activated in human microvascular ECs by tumor CM. We observed that tumor CM contained a significantly high level of VEGF. A VEGFR kinase inhibitor, Ki8751, and a phosphatidylinositol 3-kinase-Akt inhibitor, LY294002, blocked tumor CM-induced MDR1 up-regulation. MDR1 up-regulation, via the VEGF-VEGFR pathway in the tumor microenvironment, is one of the mechanisms of drug resistance acquired by TECs. We observed that VEGF secreted from tumors up-regulated MDR1 through the activation of VEGFR2 and Akt. This process is a novel mechanism of the acquisition of drug resistance by TECs in the tumor microenvironment., (Copyright © 2012 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Adipose tissue has long been considered to be a simple tissue that contains adipocytes. Because of this, the isolation and characterization of microvascular endothelical cells, which are also present in adipose tissue, have been neglected, even though they are components of a capillary network that surrounds each individual adipocyte. Here we report on a protocol for producing highly purified murine microvascular endothelial cells (MECs) from diverse sites of murine adipose tissues including inguinal and epididymal adipose tissues. The method is based on a combination of negative and positive immunomagnetic selection. The protocol involves the preparation of a single cell suspension (digestion, filtration and density gradient centrifugation), immunomagnetic enrichment of the CD45(-) cell population and the purification of the MECs by a combination of common specific markers CD31, CD102 and isolectin B4. The isolated MECs can be successively cultured for 10 to 12 passages without any detectable changes in morphology and phenotype. Therefore, the method described herein represents a protocol for the isolation and long-term maintenance of highly pure mouse MECs in high yields from adipose tissues.

Tumor angiogenesis is necessary for solid tumor progression and metastasis. Increasing evidence indicates that tumor endothelial cells (TECs) are more relevant to the study of tumor angiogenesis than normal endothelial cells (NECs) because their morphologies and gene expression are different from NECs. However, it is challenging to isolate and culture large numbers of pure ECs from tumor tissue since the percentage of ECs is only about 1-2% and tumor cells and fibroblasts easily overgrow them. In addition, there has been concern that isolated TECs may lose their special phenotype once they are dissociated from tumor cells. In this study, we have successfully purified murine TECs from four different human tumor xenografts and NECs from murine dermal tissue. Isolated ECs expressed endothelial markers, such as CD31, VE-cadherin (CD144), and endoglin (CD105), for more than 3 months after isolation. TECs maintained tumor endothelial-specific markers, such as tumor endothelial marker 8 (TEM8) and aminopeptidase N (APN), as in tumor blood vessels in vivo. In addition, TECs were more proliferative and motile than NECs. TECs showed a higher response to VEGF and higher expression of VEGF receptors-1 and -2 than NECs did. Stem cell antigen-1 was up-regulated in all four TECs, suggesting that they have a kind of stemness. Cultured TECs maintain distinct biological differences from NECs as in vivo. In conclusion, it was suggested that TECs are relevant material for tumor angiogenesis research., (2010 Elsevier Inc. All rights reserved.)

Tumor blood vessels are thought to contain genetically normal and stable endothelial cells (ECs), unlike tumor cells, which typically display genetic instability. Yet, chromosomal aberration in human tumor-associated ECs (hTECs) in carcinoma has not yet been investigated. Here we isolated TECs from 20 human renal cell carcinomas and analyzed their cytogenetic abnormalities. The degree of aneuploidy was analyzed by fluorescence in situ hybridization using chromosome 7 and chromosome 8 DNA probes in isolated hTECs. In human renal cell carcinomas, 22-58% (median, 33%) of uncultured hTECs were aneuploid, whereas normal ECs were diploid. The mechanisms governing TEC aneuploidy were then studied using mouse TECs (mTECs) isolated from xenografts of human epithelial tumors. To investigate the contribution of progenitor cells to aneuploidy in mTECs, CD133(+) and CD133(-) mTECs were compared for aneuploidy. CD133(+) mTECs showed aneuploidy more frequently than CD133(-) mTECs. This is the first report showing cytogenetic abnormality of hTECs in carcinoma, contrary to traditional belief. Cytogenetic alterations in tumor vessels of carcinoma therefore can occur and may play a significant role in modifying tumor- stromal interactions.

We describe here a procedure of endoscopic removal of a gutta-percha point under the maxillary sinus mucosa by using an ultrathin arthroscope. In this study, a 1.2-mm-diameter ultrathin arthroscope was introduced for observation into the maxillary sinus. The surgical technique is suggested to be a reliable and minimally invasive procedure that provides limited incision and bone removal and respects the integrity of the sinus.

A 54-year-old man presented with an 8-year history of a hard asymptomatic mass of the left submandibular area. Total excision of the left submandibular gland with radical neck dissection was performed under a diagnosis of a submandibular tumor, probably a malignant mixed tumor. The pathologic diagnosis was carcinosarcoma consisting of carcinomatous and sarcomatous elements. The epithelial component was composed of squamous cell carcinoma, undifferentiated carcinoma, and adenocarcinoma. The nonepithelial component was composed of chondrosarcoma, osteosarcoma, spindle cell sarcoma, rhabdomyosarcoma, and liposarcoma. In the central area of the tumor, a few remnants of benign pleomorphic adenoma were identifiable. The finding suggested that in our patient, the carcinosarcoma arose from a preexisting pleomorphic adenoma. In view of the expected aggressive nature of the tumor, the patient was treated with postoperative radiotherapy of 60 Gy total, in 30 daily fractions of 2 Gy, and chemotherapy. He currently remains well and free of disease 24 months after treatment.

Two proteins stimulating the GTPase activity of the smg-21 GTP-binding protein (smg p21) having the same effector domain as the ras proteins (ras p21s) are partially purified from the cytosol fraction of human platelets. These proteins, designated as smg p21 GTPase activating protein (GAP) 1 and 2, do not stimulate the GTPase activity of c-Ha-ras p21. The GAP activity for c-Ha-ras p21 is also detected in the cytosol fraction of human platelets. smg p21 GAP1 and 2 are separated from c-Ha-ras p21 GAP by column chromatographies. The activity of smg p21 GAP1 and 2 is killed by tryptic digestion or heat boiling. The Mr values of smg p21 GAP1 and 2 are similar and are estimated to be 2.5-3.5 x 10(5) by gel filtration analysis. These results indicate that there are two GAPs for smg p21 in addition to a GAP for c-Ha-ras p21 in human platelets.

A novel regulatory protein for rhoB p20, a ras p21-like GTP-binding protein (G protein), was partially purified from the cytosol fraction of rabbit intestine. This protein, designated as rhoB p20 GDP dissociation inhibitor (GDI), inhibited the dissociation of GDP from rhoB p20. rhoB p20 GDI also inhibited the binding of guanosine 5'-(3-O-thio)triphosphate (GTP gamma S) to the GDP-bound form of rhoB p20 but not of that to the guanine nucleotide-free form. GDI did not affect the GTPase activity of rhoB p20 and by itself showed no GTP gamma S-binding activity. GDI was inactive for other ras p21/ras p21-like G proteins including c-Ha-ras p21, smg p21 and smg p25A. The Mr value of GDI was estimated to be about 27,000 from the S value. These results indicate that rabbit intestine contains a novel regulatory protein that inhibits the dissociation of GDP from and thereby the subsequent binding of GTP to rhoB p20.