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Background: Molecules that are highly expressed in tumour endothelial cells (TECs) may be candidates for specifically targeting TECs. Using DNA microarray analysis, we found that the lysyl oxidase (LOX) gene was upregulated in TECs compared with its expression in normal endothelial cells (NECs). LOX is an enzyme that enhances invasion and metastasis of tumour cells. However, there are no reports on the function of LOX in isolated TECs.Methods: TECs and NECs were isolated to investigate LOX function in TECs. LOX inhibition of in vivo tumour growth was also assessed using β-aminopropionitrile (BAPN).Results: LOX expression was higher in TECs than in NECs. LOX knockdown inhibited cell migration and tube formation by TECs, which was associated with decreased phosphorylation of focal adhesion kinase (Tyr 397). Immunostaining showed high LOX expression in human tumour vessels in vivo. Tumour angiogenesis and micrometastasis were inhibited by BAPN in an in vivo tumour model.Conclusion: LOX may be a TEC marker and a possible therapeutic target for novel antiangiogenic therapy. [ABSTRACT FROM AUTHOR]

Background:We isolated tumour endothelial cells (TECs), demonstrated their abnormalities, compared gene expression profiles of TECs and normal endothelial cells (NECs) by microarray analysis and identified several genes upregulated in TECs. We focused on the gene encoding biglycan, a small leucine-rich repeat proteoglycan. No report is available on biglycan expression or function in TECs.Methods:The NEC and TEC were isolated. We investigated the biglycan expression and function in TECs. Western blotting analysis of biglycan was performed on sera from cancer patients.Results:Biglycan expression levels were higher in TECs than in NECs. Biglycan knockdown inhibited cell migration and caused morphological changes in TECs. Furthermore, immunostaining revealed strong biglycan expression in vivo in human tumour vessels, as in mouse TECs. Biglycan was detected in the sera of cancer patients but was hardly detected in those of healthy volunteers.Conclusion:These findings suggested that biglycan is a novel TEC marker and a target for anti-angiogenic therapy. [ABSTRACT FROM AUTHOR]

Background: Tumour stromal cells differ from its normal counterpart. We have shown that tumour endothelial cells (TECs) isolated from tumour tissues are also abnormal. Furthermore, we found that mRNAs of vascular endothelial growth factor-A (VEGF-A) and cyclooxygenase-2 (COX-2) were upregulated in TECs. Vascular endothelial growth factor-A and COX-2 are angiogenic factors and their mRNAs contain an AU-rich element (ARE). AU-rich element-containing mRNAs are reportedly stabilised by Hu antigen R (HuR), which is exported to the cytoplasm.Methods: Normal endothelial cell (NEC) and two types of TECs were isolated. We evaluated the correlation of HuR and accumulation of VEGF-A and COX-2 mRNAs in TECs and effects of HuR on biological phenotypes of TECs.Results: The HuR protein was accumulated in the cytoplasm of TECs, but not in NECs. Vascular endothelial growth factor-A and COX-2 mRNA levels decreased due to HuR knockdown and it was shown that these ARE-mRNA were bound to HuR in TECs. Furthermore, HuR knockdown inhibited cell survival, random motility, tube formation, and Akt phosphorylation in TECs.Conclusion: Hu antigen R is associated with the upregulation of VEGF-A and COX-2 mRNA in TECs, and has an important role in keeping an angiogenic switch on, through activating angiogenic phenotype in tumour endothelium. [ABSTRACT FROM AUTHOR]

HuR, a ubiquitously expressed member of the Hu protein family that binds and stabilizes an AU-rich element (ARE)-containing mRNAs, is known to shuttle between the nucleus and the cytoplasm via several export pathways. When normal cells were treated with heat shock, HuR was exported to the cytoplasm in a chromosome maintenance region 1 (CRM1)-dependent manner. However, in this study, we demonstrate that HuR is exported to the cytoplasm in oral cancer cells even if the cells were treated with the inhibitor of the CRM1-independent export pathway. Immunohistochemical and biochemical analyses showed that HuR existed in both the cytoplasm and the nucleus in oral cancer cells, such as HSC-3 and Ca9.22, but existed entirely inside the nucleus in normal cells. AU-rich element-mRNAs were also exported to the cytoplasm and stabilised in the oral cancer cells, which were inhibited by HuR knockdown. This export of HuR was not affected by at least 7 h of treatment of leptomycin B (LMB), which is an inhibitor of the CRM1-dependent export pathway. These findings suggest that HuR is exported to the cytoplasm in oral carcinoma cells in a different manner from that of normal cells, and is likely to occur through the perturbation of a normal export pathway. [ABSTRACT FROM AUTHOR]

Relatively large amounts of inorganic polyphosphate [poly(P)] (400 μM) have been found in normal osteoblasts. The effect of poly(P) with an average chain length of 65 phosphate residues on cell calcification was therefore investigated with the use of MC3T3-E1 cells. Expression of both osteopontin and osteocalcin was induced by poly(P) (0.1 ∼ 1 mM), and cells treated with poly(P) were strongly stained by alizarin red. In addition, the level of alkaline phosphatase activity induced in poly(P)-treated cells was two-fold higher than that in either orthophosphate-treated or control cells but not higher than that in cells treated with β-glycerophosphate and ascorbic acid. In contrast, however, polyphosphatase activities were activated by poly(P) treatment to levels up to six-fold greater than that in controls. MC3T3-E1 cells may utilize poly(P) as a phosphate source for calcification rather than phosphate sources that are mainly produced by ALPase. Poly(P)-dependent induction of polyphosphatase activities may therefore promote calcification in MC3T3-E1 cells. [ABSTRACT FROM AUTHOR]

To investigate the clinical significance of circulating angiogenic factors, especially in association with early relapse of osteosarcoma, we quantified pre-therapeutic levels of vascular endothelial growth factor, basic fibroblast growth factor and placenta growth factor in the sera of 16 patients with osteosarcoma using an enzyme-linked immunosorbent assay. After a 1-year follow-up, the serum level of angiogenic factors was analysed with respect to microvessel density of the biopsy specimen and clinical disease relapse. The serum vascular endothelial growth factor levels were positively correlated with the microvessel density with statistical significance (P=0.004; Spearman rank correlation) and also significantly higher in seven patients who developed pulmonary metastasis than the remaining nine patients without detectable disease relapse (P=0.0009; The Mann-Whitney U-test). In contrast, the serum levels of basic fibroblast growth factor or placenta growth factor failed to show significant correlation with the microvessel density or relapse of the disease. Although there was no significant correlation between serum vascular endothelial growth factor levels and the tumour volume, the serum vascular endothelial growth factor levels were significantly higher in patients with a vascular endothelial growth factor-positive tumour than those with a vascular endothelial growth factor-negative tumour. These findings suggest that the pre-therapeutic serum vascular endothelial growth factor level reflects the angiogenic property of primary tumour and may have a predictive value on early disease relapse of osteosarcoma. [ABSTRACT FROM AUTHOR]

Salivary gland scintigraphy was performed on 52 patients who were suspected of having Sjögren's syndrome (SS), and the results were compared with clinicopathologic features of the salivary and lacrimal glands. The time-activity curves which were obtained from computer-assisted analysis of 99mTc-pertechnetate (99mTc) scintigraphy were classified into four types (normal, median, flat and sloped types). The stimulated parotid flow rate decreased and the incidence of SS-related sialographic and histopathologic findings increased significantly as the scintigraphic abnormality advanced. In addition, the lacrimal gland function decreased and the proportion of patients diagnosed as having keratoconjunctivitis sicca (KCS) increased significantly as the scintigraphic abnormality advanced. These results indicate that the results of scintigraphy are related not only to the clinicopathologic features of the salivary glands but also to the lacrimal gland function in SS. [ABSTRACT FROM AUTHOR]

Unilateral maxillary or mandibular molars were extracted from twenty-four, 25-day-old male syrian golden hamsters; 25 days after extraction, 20 received MNU intragastrically twice a week for 3 months. All animals were killed 1 month later. High degrees and incidence of invasion of gingival SCC were observed in dentulous jaws without functional occlusion, followed by dentulous jaws with functional occlusion and edentulous jaws. Invasion of carcinomas with extensive bone destruction was observed commonly in the gingiva of dentulous maxillary jaws without functional occlusion, but was scarcely observed in the gingiva of edentulous jaws. By analogy, disuse atrophy of the periodontium due to loss of functional occlusion may result in early deeper invasion, while loss of peridontal ligament due to tooth extraction and disappearance of so-called inner gingival epithelium may result in less invasive carcinomas. [ABSTRACT FROM AUTHOR]

src homology 2 (SH2)-containing protein-tyrosine phosphatase SHP2 is known to transduce positive signals from activated receptor protein-tyrosine kinases such as platelet-derived growth factor receptor (PDGFR) beta and insulin receptor. Here, we demonstrate the physiological expression of SHP2 in rats. In northern and western blot analyses, SHP2 expressions were recognized in all tissues, but their expression levels varied significantly among tissues: it is lowest in the liver and kidney. Immunohistochemical staining and in situ hybridization showed SHP2 was expressed ubiquitously but predominantly in vascular smooth muscle cells (SMC). During the development of granulations. SHP2 was expressed predominantly in vascular SMC and also highly expressed in capillary cells. The functional associations of SHP2 with PDGFR beta, which transduces major growth signals in vascular SMC, identify a crucial function of SHP2 in blood vessels in consert with PDGFR beta. [ABSTRACT FROM AUTHOR]

Presents information on a study which investigated the thermal stability and oxidation resistance of hydrogenation decomposition desorption recombination processed samarium-iron-titanium-boron-nitrogen (Sm-Fe-Ti-B-N) bonded magnets. Methodology; Temperature coefficients of Bromine and iHc of the bonded magnets; Irreversible loss of the bonded magnets; Oxidation resistance of Sm-Fe-Ti-B-N, Sm-Fe-N and Neodymium-Fe-Cobalt-B powders.

Tumor angiogenesis is essential for tumor progression. The inhibition of tumor angiogenesis is a promising therapy for tumors. Bovine lactoferrin (bLF) has been reported as an anti-tumor agent. However, bLF effects on tumor angiogenesis are not well demonstrated. This study evaluated the inhibitory effects of bLF on tumor angiogenesis in vivo and in vitro. Herein, tumor endothelial cells (TECs) and normal endothelial cells (NECs) were used. Proliferation, migration, tube formation assays, RT-PCR, flow cytometry, Western blotting, siRNA experiments and immunoprecipitation were conducted to clarify the mechanisms of bLF-induced effects. CD-31 immunoexpression was examined in tumor tissues of oral squamous cell carcinoma mouse models with or without Liposomal bLF (LbLF)-administration. We confirmed that bLF inhibited proliferation/migration/tube formation and increased apoptosis in TECs but not NECs. TNF receptor-associated factor 6 (TRAF6), p-p65, hypoxia inducible factor-α (HIF-1α) and vascular endothelial growth factor (VEGF) were highly expressed in TECs. In TECs, bLF markedly downregulated VEGF-A, VEGF receptor (VEGFR) and HIF-1α via the inhibition of p-p65 through binding with TRAF6. Since NECs slightly expressed p-p65, bLF-TRAF-6 binding could not induce detectable changes. Moreover, orally administrated LbLF decreased CD31-positive microvascular density only in TECs. Hence, bLF specifically suppressed tumor angiogenesis through p-p65 inhibition by binding to TRAF6 and suppressing HIF-1α activation followed by VEGF/VEGFR down-regulation. Collectively, bLF can be an anti-angiogenic agent for tumors.

Oral squamous cell carcinoma (OSCC) impairs functionality and sensuousness resulting in poor quality of life. Biomarkers can predict disease trajectory and lead to effective treatments. Transcriptomics have identified genes that are upregulated in tumor endothelial cells (TECs) compared with normal endothelial cells (NECs). Among them, chemokine receptor 7 (CXCR7) is highly expressed in TECs of several cancers and involved in angiogenesis of TECs. However, levels of CXCR7 in OSCC blood vessels have not been fully investigated. In this study, we analyzed the correlation between CXCR7 expression in TECs and clinicopathological factors in OSCC. Immunohistochemistry for CXCR7 and CD34 was performed on 59 OSCC tissue specimens resected between 1996 and 2008 at Hokkaido University Hospital. CXCR7 expression in blood vessels was evaluated by the ratio of CXCR7+/CD34+ blood vessels. CXCR7 expression was 42% and 19% in tumor and non-tumor parts, respectively, suggesting that CXCR7 expression is higher in TECs than in NECs. CXCR7 expression in TECs correlated with advanced T-stage and cancer stage. Overall survival and disease-free survival rates were higher in low-expressing CXCR7 patients than in high-expressing. These results suggest that CXCR7 expression in blood vessels may be a useful diagnostic and prognostic marker for OSCC patients., (© 2021 Japanese Society of Pathology and John Wiley & Sons Australia, Ltd.)

AU-rich elements (AREs) are RNA elements that enhance the rapid decay of mRNAs, including those of genes required for cell growth and proliferation. HuR, a member of the embryonic lethal abnormal vision (ELAV) family of RNA-binding proteins, is involved in the stabilization of ARE-mRNA. The level of HuR in the cytoplasm is up-regulated in most cancer cells, resulting in the stabilization of ARE-mRNA. We developed the adenoviruses AdARET and AdAREF, which include the ARE of TNF- α and c-fos genes in the 3'-untranslated regions of the E1A gene, respectively. The expression of the E1A protein was higher in cancer cells than in normal cells, and virus production and cytolytic activities were also higher in many types of cancer cells. The inhibition of ARE-mRNA stabilization resulted in a reduction in viral replication, demonstrating that the stabilization system was required for production of the virus. The growth of human tumors that formed in nude mice was inhibited by an intratumoral injection of AdARET and AdAREF. These results indicate that these viruses have potential as oncolytic adenoviruses in the vast majority of cancers in which ARE-mRNA is stabilized., Competing Interests: The authors declare no conflicts of interest.

AU-rich elements (AREs) are RNA elements that enhance the rapid decay of mRNA. The fate of ARE-mRNA is controlled by ARE-binding proteins. HuR, a member of the embryonic lethal abnormal vision (ELAV) family of RNA-binding proteins, is involved in the export and stabilization of ARE-mRNA. In the vast majority of cancer cells, HuR constitutively relocates to the cytoplasm, resulting in the stabilization of ARE-mRNA. Previously, we described that the adenovirus gene product, E4orf6, which is necessary for virus replication, participates in ARE-mRNA export and stabilization. In the present study, we showed the oncolytic potential of E4orf6-deleted adenovirus dl355, which is expected to be replicated selectively in cancer cells. Virus production and cytolytic activity of dl355 were higher in cancer cells than in normal cells. HuR-depletion downregulated dl355 replication, demonstrating that ARE-mRNA stabilization is required for the production of this virus. Tumor growth was inhibited in nude mice by an intratumoral injection of dl355. Furthermore, dl355 had a stronger oncolytic effect than E1B55k-deleted adenovirus. These results indicate that dl355 has potential as an oncolytic adenovirus for a large number of cancers where ARE-mRNA is stabilized.

Special AT-rich sequence-binding protein 2 (SATB2)-associated syndrome (SAS) is characterized by alterations of SATB2. Its clinical features include intellectual disability and craniofacial abnormalities, such as cleft palate, dysmorphic features, and dental abnormalities. Here, we describe three previously undiagnosed, unrelated patients with SAS who exhibited dental abnormalities, including multiple odontomas. Although isolated odontomas are common, multiple odontomas are rare. Individuals in families 1 and 3 underwent whole-exome sequencing. Patient 2 and parents underwent targeted amplicon sequencing. On the basis of the hg19/GRCh37 reference and the RefSeq mRNA NM_001172517, respective heterozygous mutations were found and validated in Patients 1, 2, and 3: a splice-site mutation (chr2:g.200137396C > T, c.1741-1G > A), a nonsense mutation (chr2:g.200213750G > A, c.847C > T, p.R283*), and a frame-shift mutations (chr2:g.200188589_200188590del, c.1478_1479del, p.Q493Rfs*19). All mutations occurred de novo. The mutations in Patients 1 and 3 were novel; the mutation in Patient 2 has been described previously. Tooth mesenchymal cells derived from Patient 2 showed diminished SATB2 expression. Multiple odontomas were evident in the patients in this report; however, this has not been recognized previously as a SAS-associated phenotype. We propose that multiple odontomas be considered as an occasional manifestation of SAS., (© 2018 Wiley Periodicals, Inc.)

Human antigen R (HuR) is a RNA-binding protein, which binds to the AU-rich element (ARE) in the 3'-untranslated region (3'-UTR) of certain mRNA and is involved in the export and stabilization of ARE-mRNA. HuR constitutively relocates to the cytoplasm in many cancer cells, however the mechanism of intracellular HuR trafficking is poorly understood. To address this question, we examined the functional role of the cytoskeleton in HuR relocalization. We tested the effect of actin depolymerizing macrolide latrunculin A or myosin II ATPase activity inhibitor blebbistatin for HuR relocalization induced by the vasoactive hormone Angiotensin II in cancer and control normal cells. Western blot and confocal imaging data revealed that both inhibitors attenuated the cytoplasmic HuR in normal cells but no such alteration was observed in cancer cells. Concomitant with changes in intracellular HuR localization, both inhibitors markedly decreased the accumulation and half-lives of HuR target ARE-mRNAs in normal cells, whereas no change was observed in cancer cells. Furthermore, co-immunoprecipitation experiments with HuR proteins revealed clear physical interaction with ß-actin only in normal cells. The current study is the first to verify that cancer cells can implicate a microfilament independent HuR transport. We hypothesized that when cytoskeleton structure is impaired, cancer cells can acquire an alternative HuR trafficking strategy., (Copyright © 2018 Elsevier Inc. All rights reserved.)

HuR is an RNA-binding protein of the embryonic lethal abnormal vision (ELAV) family, which binds to the AU-rich element (ARE) in the 3'-untranslated region (UTR) of certain mRNAs and is involved in the nucleo-cytoplasmic export and stabilization of ARE-mRNAs. The cytoplasmic relocalization of ARE-mRNAs with several proteins such as HuR and pp32 increases in cells transformed by the adenovirus oncogene product E4orf6. Additionally, these ARE-mRNAs were stabilized and acquired the potential to transform cells. Although, the relocalization of HuR and the stabilization of ARE-mRNAs are crucial for cell transformation, evidence regarding the relationship of HuR and ARE-mRNAs with adenovirus replication is lacking. In this report, we demonstrate that adenovirus infection induces the relocation of HuR to the cytoplasm of host cells. Analysis using the luciferase-ARE fusion gene and the tetracycline (tet)-off system revealed that the process of stabilizing ARE-mRNAs is activated in adenovirus-infected cells. Heat shock treatment or knockdown-mediated depletion of HuR reduced adenovirus production. Furthermore, expression of ARE-including viral IVa2 mRNA, decreased in HuR-depleted infected cells. These results indicate that HuR plays an important role in adenovirus replication, at least in part, by up-regulating IVa2 mRNA expression and that ARE-mRNA stabilization is required for both transformation and virus replication., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Tumor blood vessels play an important role in tumor progression and metastasis. We previously reported that tumor endothelial cells (TEC) exhibit several altered phenotypes compared with normal endothelial cells (NEC). For example, TEC have chromosomal abnormalities and are resistant to several anticancer drugs. Furthermore, TEC contain stem cell-like populations with high aldehyde dehydrogenase (ALDH) activity (ALDH high TEC). ALDH high TEC have proangiogenic properties compared with ALDH low TEC. However, the association between ALDH high TEC and drug resistance remains unclear. In the present study, we found that ALDH mRNA expression and activity were higher in both human and mouse TEC than in NEC. Human NEC:human microvascular endothelial cells (HMVEC) were treated with tumor-conditioned medium (tumor CM). The ALDH high population increased along with upregulation of stem-related genes such as multidrug resistance 1, CD90, ALP, and Oct-4. Tumor CM also induced sphere-forming ability in HMVEC. Platelet-derived growth factor (PDGF)-A in tumor CM was shown to induce ALDH expression in HMVEC. Finally, ALDH high TEC were resistant to fluorouracil (5-FU) in vitro and in vivo. ALDH high TEC showed a higher grade of aneuploidy compared with that in ALDH low TEC. These results suggested that tumor-secreting factor increases ALDH high TEC populations that are resistant to 5-FU. Therefore, ALDH high TEC in tumor blood vessels might be an important target to overcome or prevent drug resistance., (© 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.)

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.)

Tumor progression is dependent on tumor angiogenesis. We previously reported that the phenotype of tumor endothelial cells (TECs) is distinct from normal endothelial cells (NECs). Herein, we conducted a pathway analysis using a public TEC microarray database and identified several putative TEC-specific miRNAs. We found that miR-145 expression was upregulated in TECs and that miR-145 enhanced cell adhesion and anoikis resistance and upregulated Bcl-2 and Bcl-xl via ERK1/2 in human microvascular endothelial cells. These findings suggested that miR-145 is involved in the acquisition of the TEC phenotype, partially. Therefore, miR-145 and its target genes may be molecular targets for anti-angiogenic therapy., (© The Authors 2017. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.)

Reactive oxygen species (ROS) are unstable molecules that activate oxidative stress. Because of the insufficient blood flow in tumors, the tumor microenvironment is often exposed to hypoxic condition and nutrient deprivation, which induces ROS accumulation. We isolated tumor endothelial cells (TECs) and found that they have various abnormalities, although the underlying mechanisms are not fully understood. Here we showed that ROS were accumulated in tumor blood vessels and ROS enhanced TEC migration with upregulation of several angiogenesis related gene expressions. It was also demonstrated that these genes were upregulated by regulation of Nuclear factor erythroid 2-related factor 2 (NRF2). Among these genes, we focused on Biglycan, a small leucine-rich proteoglycan. Inhibition of Toll-like receptors 2 and 4, known BIGLYCAN (BGN) receptors, cancelled the TEC motility stimulated by ROS. ROS inhibited NRF2 expression in TECs but not in NECs, and NRF2 inhibited phosphorylation of SMAD2/3, which activates transcription of BGN. These results indicated that ROS-induced BGN caused the pro-angiogenic phenotype in TECs via NRF2 dysregulation.

Aim: We evaluated the prognostic value of vasohibin-1 (VASH1) expression in head and neck squamous cell carcinoma., Materials and Methods: Immunohistochemistry for VASH1 and cluster of differentiation 34 (CD34) was performed on 61 head and neck squamous cell carcinoma specimens. The association between VASH1 expression in the tumour and clinical outcomes was analyzed statistically., Results: VASH1 staining in normal tissue adjacent to cancerous tissue was negative, whereas it was positive in tumour blood vessels and AE1/AE3 and Ki67-positive tumour cells. Therefore, we examined the association between VASH1 expression in the tumour and clinical outcomes. Patients with high VASH1 expression in tumour had significantly shorter disease-free survival and more frequently had lymph node recurrence than those with low VASH1 expression., Conclusion: These results suggest that VASH1 expression is associated with tumour progression and may be useful as a prognostic marker of head and neck squamous cell carcinoma., (Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Oral leukoplakia (OL) is a clinically diagnosed preneoplastic lesion of the oral cavity with an increased oral cancer risk. However, the risk of malignant transformation is still difficult to assess. The objective of the present study was to examine the expression patterns of aldehyde dehydrogenase 1 (ALDH1) and podoplanin in OL, and to determine their roles in predicting oral cancer development. In the present study, the expression patterns of ALDH1 and podoplanin were determined in samples from 79 patients with OL. The association between protein expression and clinicopathological parameters, including oral cancer-free survival, was analyzed during a mean follow-up period of 3.4 years. Expression of ALDH1 and podoplanin was observed in 61 and 67% patients, respectively. Kaplan-Meier analysis demonstrated that the expression of the proteins was correlated with the risk of progression to oral cancer. Multivariate analysis revealed that expression of ALDH1 and podoplanin was associated with 3.02- and 2.62-fold increased risk of malignant transformation, respectively. The malignant transformation risk of OL was considerably higher in cases with expression of both proteins. Point-prevalence analysis revealed that 66% of patients with co-expression of ALDH1 and podoplanin developed oral cancer. Taken together, our data indicate that ALDH1 and podoplanin expression patterns in OL are associated with oral cancer development, suggesting that ALDH1 and podoplanin may be useful biomarkers to identify OL patients with a substantially high oral cancer risk.

It has been described that tumor progression has many similarities to inflammation and wound healing in terms of the signaling processes involved. Among biological responses, angiogenesis, which is necessary for tumor progression and metastasis, is a common hallmark; therefore, tumor blood vessels have been considered as important therapeutic targets in anticancer therapy. We focused on pentraxin 3 (PTX3), which is a marker of cancer-related inflammation, but we found no reports on its expression and function in tumor blood vessels. Here we showed that PTX3 is expressed in mouse and human tumor blood vessels based on immunohistochemical analysis. We found that PTX3 is upregulated in primary mouse and human tumor endothelial cells compared to normal endothelial cells. We also showed that PTX3 plays an important role in the proliferation of the tumor endothelial cells. These results suggest that PTX3 is an important target for antiangiogenic therapy., (© 2016 Japanese Society of Pathology and John Wiley & Sons Australia, Ltd.)

The risk of malignant transformation in oral preneoplastic lesions (OPLs) is challenging to assess. The objective of the present study was to determine the expression of ELAV like RNA binding protein 1 (HuR) and podoplanin in OPLs, and to evaluate the use of each protein as biomarkers for the risk assessment of malignant transformations. Immunohistochemistry for HuR and podoplanin was performed on the tissues of 51 patients with OPL, including cases of low grade dysplasia (LGD) and high grade dysplasia (HGD). The association between the protein expression patterns and clinicopathological parameters, including oral cancer free survival (OCFS) time, was analyzed during the follow-up period. HuR and podoplanin expression was observed in 28 (55%) and 36 (71%) of 51 patients, respectively. Kaplan-Meier analysis showed that the expression of HuR and podoplanin was associated with the risk of progression to oral cancer (P<0.05). Multivariate analysis revealed that HuR and podoplanin expression was associated with a 2.93-fold (95% confidence interval (CI), 0.98-10.34; P=0.055) and 2.06-fold (95% CI, 0.55-8.01; P=0.283) increase in risk of malignant transformation, respectively. The risk of OPL malignant transformation was considerably increased with the coexpression of HuR and podoplanin compared with the histological grading (95% CI, 1.64-23.59; P=0.005). The results of the present study demonstrated that the expression of HuR and podoplanin associates with malignant transformation and suggests that the proteins may be used as biomarkers to identify OPL patients with an increased risk of cancer development.

Tumour blood vessels are gateways for distant metastasis. Recent studies have revealed that tumour endothelial cells (TECs) demonstrate distinct phenotypes from their normal counterparts. We have demonstrated that features of TECs are different depending on tumour malignancy, suggesting that TECs communicate with surrounding tumour cells. However, the contribution of TECs to metastasis has not been elucidated. Here, we show that TECs actively promote tumour metastasis through a bidirectional interaction between tumour cells and TECs. Co-implantation of TECs isolated from highly metastatic tumours accelerated lung metastases of low metastatic tumours. Biglycan, a small leucine-rich repeat proteoglycan secreted from TECs, activated tumour cell migration via nuclear factor-κB and extracellular signal-regulated kinase 1/2. Biglycan expression was upregulated by DNA demethylation in TECs. Collectively, our results demonstrate that TECs are altered in their microenvironment and, in turn, instigate tumour cells to metastasize, which is a novel mechanism for tumour metastasis.