VEGF-D Research Articles

Regulation of expression level of fms-like tyrosine kinase-4 is related to osteoclast differentiation.

IntroductionThe aim of this study is to determine whether regulation of the expression level of fms-like tyrosine kinase-4 (Flt-4) is related to osteoclast differentiation.Material and methodsOsteoclast formation and differentiation of mouse bone marrow cells and RAW264.7 cells were performed. To induce osteoclast differentiation, RANKL (50 ng/ml) with or without vascular endothelial growth factor-C (VEGF-C) and vascular endothelial growth factor-D (VEGF-D) was added to mouse bone marrow cells and RAW264.7 cells. Then cells were examined under a microscope. TRAP-positive cells with 3 nuclei or more were considered as osteoclasts and counted. The Flt-4 gene was knocked down by transfection of siRNAs against Flt-4. Immunoblot analyses were performed.ResultsThe osteoclast formation assay indicated that VEGF-C resulted in 500 or 450 vs. 100 (p < 0.05) of osteoclasts in mouse bone marrow cells and RAW264.7 cells, respectively. Vascular endothelial growth factor-D resulted in about 600 or 630 vs. 100 (p < 0.05) of osteoclasts for both mouse bone marrow cells and RAW264.7 cells. The knock-down of Flt-4 expression abolished the induction by VEGF-C or VEGF-D, resulting in induction similar to that of the negative control PBS.ConclusionsBoth VEGF-C and VEGF-D can induce osteoclast differentiation in the presence of the receptor activator of nuclear factor κB ligand. Down-regulation of expression level of Flt-4 protein abolishes osteoclast differentiation induced by VEGF-C or VEGF-D.

Pharmacological targeting of VEGFR signaling with axitinib inhibits Tsc2-null lesion growth in the mouse model of lymphangioleiomyomatosis

Pulmonary lymphangioleiomyomatosis (LAM), a rare progressive lung disease associated with mutations of the tuberous sclerosis complex 2 (Tsc2) tumor suppressor gene, manifests by neoplastic growth of LAM cells, induction of cystic lung destruction, and respiratory failure. LAM severity correlates with upregulation in serum of the prolymphangiogenic vascular endothelial growth factor D (VEGF-D) that distinguishes LAM from other cystic diseases. The goals of our study was to determine whether Tsc2 deficiency upregulates VEGF-D, and whether axitinib, the Food and Drug Administration-approved small-molecule inhibitor of VEGF receptor (VEGFR) signaling, will reduce Tsc2-null lung lesion growth in a mouse model of LAM. Our data demonstrate upregulation of VEGF-D in the serum and lung lining in mice with Tsc2-null lesions. Progressive growth of Tsc2-null lesions induces recruitment and activation of inflammatory cells and increased nitric oxide production. Recruited cells isolated from the lung lining of mice with Tsc2-null lesions demonstrate upregulated expression of provasculogenic Vegfa, prolymphangiogenic Figf, and proinflammatory Nos2, Il6, and Ccl2 genes. Importantly, axitinib is an effective inhibitor of Tsc2-null lesion growth and inflammatory cell recruitment, which correlates with reduced VEGF-D levels in serum and lung lining. Our data demonstrate that pharmacological inhibition of VEGFR signaling with axitinib inhibits Tsc2-null lesion growth, attenuates recruitment and activation of inflammatory cells, and reduces VEGF-D levels systemically and in the lung lining. Our study suggests a potential therapeutic benefit of inhibition of VEGFR signaling for treatment of LAM.

Serum Vascular Endothelial Growth Factor-D in Patients With Cystic Lung Diseases

Serum Vascular Endothelial Growth Factor-D in Patients With Cystic Lung Diseases

Correlation of serum vascular endothelial growth factor-D concentration with clinical presentation and course of lymphangioleiomyomatosis

BackgroundIncreased serum vascular endothelial growth factor D (VEGF-D) concentration has been accepted as a diagnostic marker in lymphangioleiomyomatosis (LAM). The study was performed to evaluate the correlation of VEGF-D with clinical presentation and course of LAM. MaterialThe study group comprised of 48 women with LAM (27 with sLAM, 9 with sLAM and lymphangioma (sLAM-LYM) and 12 patients with TSC/LAM). Patients were assessed at the time of VEGF-D examination, and pulmonary function parameters were compared with those, obtained one year before. VEGF-D serum concentration was measured by ELISA method. ResultsPatients with TSC/LAM and sLAM-LYM displayed higher concentrations of VEGF-D than patients with sLAM (2682 ± 1347 pg/mL and 2223 ± 1184 pg/mL vs.1281 ± 791 pg/mL; p = 0.0002, p = 0.009) respectively. Patients with sLAM and VEGF-D concentration <800 pg/mL (sLAM-L) had better lung function as assessed by FEV1 (2.38 ± 0.88 L vs. 1.75 ± 0.8 L; p < 0.015) and DL,CO (5.8 ± 2.25 vs. 3.93 ± 1.74 mL/min/mmHg; p < 0.028), had higher blood oxygenation, then those with VEGF-D >800 pg/mL (sLAM-H). Significant yearly increase of TLC (390 ± 700 mL; p < 0.021) and RV (340 ± 790 mL; p < 0.03), and decrease of distance in 6MWT (−30 ± 50 m; p = 0.04) were observed in sLAM-H group. Lung function parameters remained constant in sLAM-L patients. Patients with sLAM-H displayed higher yearly decline of FVC (120 vs. 50 mL; p = 0.035) and increase of TLC (390 vs. −80 mL; p = 0.038) and RV (340 vs. 90 mL; p = 0.045) than sLAM-L patients. Negative correlations between VEGF-D concentration and DL,CO, PaO2, PaCO2, and positive with HRCT grading, and desaturation in 6MWT were noticed in sLAM patients without lymphangioma. ConclusionsSerum VEGF-D is the useful biomarker of LAM extension, and might also prove predictive towards therapeutic decision.

Resistance Training Outcomes Are Correlated with Muscle Vascular Endothelial Growth Factor-D in Older Adults

Resistance Training Outcomes Are Correlated with Muscle Vascular Endothelial Growth Factor-D in Older Adults

Key endothelial cell angiogenic mechanisms are stimulated by the circulating milieu in sickle cell disease and attenuated by hydroxyurea.

As hypoxia-induced inflammatory angiogenesis may contribute to the manifestations of sickle cell disease, we compared the angiogenic molecular profiles of plasma from sickle cell disease individuals and correlated these with in vitro endothelial cell-mediated angiogenesis-stimulating activity and in vivo neovascularization. Bioplex demonstrated that plasma from patients with steady-state sickle cell anemia contained elevated concentrations of pro-angiogenic factors (angiopoietin-1, basic fibroblast growth factor, vascular endothelial growth factor, vascular endothelial growth factor-D and placental growth factor) and displayed potent pro-angiogenic activity, significantly increasing endothelial cell proliferation, migration and capillary-like structure formation. In vivo neovascularization of Matrigel plugs was significantly greater in sickle cell disease mice than in non-sickle cell disease mice, consistent with an up-regulation of angiogenesis in the disease. In plasma from patients with hemoglobin SC disease without proliferative retinopathy, anti-angiogenic endostatin and thrombospondin-2 were significantly elevated. In contrast, plasma from hemoglobin SC individuals with proliferative retinopathy had a pro-angiogenic profile and more significant effects on endothelial cell proliferation and capillary formation than plasma from patients without retinopathy. Hydroxyurea therapy was associated with significant reductions in plasma angiogenic factors and inhibition of endothelial cell-mediated angiogenic mechanisms and neovascularization. Thus, individuals with sickle cell anemia or hemoglobin SC disease with retinopathy present a highly angiogenic circulating milieu, capable of stimulating key endothelial cell-mediated angiogenic mechanisms. Combination anti-angiogenic therapy to prevent the progression of unregulated neovascularization and associated manifestations in sickle cell disease, such as pulmonary hypertension, may be indicated; furthermore, the benefits and drawbacks of the potent anti-angiogenic effects of hydroxyurea should be clarified.

Management of lymphangioleiomyomatosis.

Lymphangioleiomyomatosis (LAM), a multisystem disease affecting almost exclusively women, is characterized by cystic lung destruction and presents with dyspnea, recurrent pneumothoraxes, chylous effusions, lymphangioleiomyomas, and angiomyolipomas. It is caused by the proliferation of a cancer-like LAM cell that possesses a mutation in either the tuberous sclerosis complex (TSC)1 or TSC2 genes. This article reviews current therapies and new potential treatments that are currently undergoing investigation. The major development in the treatment of LAM is the discovery of two mammalian target of rapamycin (mTOR) inhibitors, sirolimus and everolimus, as effective drugs. However, inhibition of mTOR increases autophagy, which may lead to enhanced LAM cell survival. Use of autophagy inhibitors, for example, hydroxychloroquine, in combination with sirolimus is now the subject of an ongoing drug trial (SAIL trial). Another consequence of mTOR inhibition by sirolimus is an increase in Rho activity, resulting in reduced programmed cell death. From these data, the concept evolved that a combination of sirolimus with disruption of Rho activity with statins (e.g. simvastatin) may increase TSC-null cell death and reduce LAM cell survival. A combined trial of sirolimus with simvastatin is under investigation (SOS trial). Since LAM occurs primarily in women and TSC-null cell survival and tumor growth is promoted by estrogens, the inhibition of aromatase to block estrogen synthesis is currently undergoing study (TRAIL trial). Other targets, for example, estrogen receptors, mitogen-activated protein kinase inhibitors, vascular endothelial growth factor-D signaling pathway, and Src kinase, are also being studied in experimental model systems. As in the case of cancer, combination therapy may become the treatment of choice for LAM.

Circulating Angiogenesis Biomarkers Are Associated With Disease Progression in Lung Adenocarcinoma

Dysregulation of angiogenesis is known to be associated with tumorigenesis and metastatic progression in multiple carcinomas. The aim of this study was to evaluate the prognostic value of circulating angiogenesis biomarkers in lung adenocarcinoma progression. For that,we hypothesize that circulating levels of biomarkers characteristic for discrete processes within angiogenesis are associated with specific phases of disease progression. Appreciation of these profiles may have important implications for disease detection and prognostication. Patients with lung adenocarcinoma enrolled in the study were grouped as follows: node negative (T1a-3N0M0; n= 69), node positive (T1a-4N1-2M0; n=60), and disseminated disease (TxNxM1; n= 68). All serum specimens were assayed for 17 angiogenesis biomarkers on the Luminex platform and statistically evaluated by analysis of variance for median differences in biomarker concentration at distinct phases of disease progression and by log rank methods for associations with clinical outcome. We found circulating hepatocyte growth factor, heparin-binding epidermal growth factor, epidermal growth factor, and vascular endothelial growth factor-C levels significantly elevated (p < 0.05) in patients with node positive versus node negative disease. Similarly, median serum concentrations of bone morphogenic protein-9, endoglin, fibroblast growth factor-1, fibroblast growth factor-2, interleukin-8, placental growth factor, vascular endothelial growth factor-C, and vascular endothelial growth factor-D were significantly (p < 0.05) higher in patients with disseminated disease than in patients with node positive disease. Five biomarkers total were strongly prognostic (p < 0.05) for overall survival in the node negative cohort. Angiogenesis is a process central to lung adenocarcinoma progression. We describe the modulation in serum angiogenesis biomarker concentrations through the various phases of non-small cell lung cancer progression. Additional refinement efforts are under way to enhance test performance, followed by additional validation studies.

The effects of sonic hedgehog signaling pathway components on non-small-cell lung cancer progression and clinical outcome.

BackgroundResearchers in recent studies have reported that the sonic hedgehog (Shh) signaling pathway plays a crucial role during tumorigenesis, angiogenesis and cellular differentiation. We investigated the clinical and pathological significances of the Shh pathway and of its lymphangiogenic components in non-small-cell lung cancer (NSCLC), namely, Shh, glioma-associated oncogene homolog zinc finger protein 1 (Gli1), lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1) and vascular endothelial growth factor D (VEGF-D).MethodsThe expression of Shh, Gli1, LYVE-1 and VEGF-D in primary NSCLC tissue from 40 patients was examined using immunohistochemical assays, and relationships between expression and clinicopathological data, such as age, gender, histology, tumor size, nodal stage, visceral pleural invasion, lymphatic thromboembolism, recurrence and overall survival were investigated.ResultsOf the 40 specimens examined, 25 (62.5%), 20 (50.0%), 11 (27.5%) and 20 (50.0%) were positive for Shh, Gli1, LYVE-1 or VEGF-D expression, respectively. The expression of Gli1 and LYVE-1 were significantly associated (P = 0.011), and Shh and LYVE-1 expression was related to visceral pleural invasion and lymphatic thromboembolism, respectively (P < 0.05). Shh expression levels compared on survival curves were statistically significant in univariate logrank analysis (P = 0.020). However, other clinicopathological factors did not reveal any statistical significance in univariate and multivariate analyses.ConclusionsTo our knowledge, this the first report of the relationship between components of the Shh signaling pathway and prognosis in NSCLC. The expression of Shh, Gli1 and LYVE-1 was found to be associated with clinicopathological factors and survival. Thus, the overexpression of the Shh signaling pathway could serve as a predictor of malignant behavior, including lymphangiogenesis, in NSCLC.

Lymphangioleiomyomatosis: differential diagnosis and optimal management.

Lymphangioleiomyomatosis (LAM) is an uncommon disease presented as diffuse thin-walled cystic changes in the lung. The main differential diagnoses include pulmonary Langerhans’ histiocytosis (PLCH), Birt-Hogg-Dubé syndrome (BHD), lymphoid interstitial pneumonia (LIP), and amyloidosis. A combination of clinical, radiological, and pathological approaches as well as genetic testing will clarify the diagnosis in most cases. LAM is a disease almost exclusively in women. Dyspnea, pneumothorax, and hemoptysis are common presentations in LAM patients. LAM is also a lymphatic disorder affecting lymphatic vessels and lymph nodes. Chylothorax, chylous ascites, and lymphangiomyomas are frequently seen. LAM can present sporadically as a single entity or as part of tuberous sclerosis complex (TSC). Angiomyolipoma (AML) is a characteristic extra-pulmonary lesion, either found in association with sporadic or TSC-related LAM. High-risk populations should be screened for LAM, including adult women with TSC and female patients with spontaneous pneumothorax, AMLs in the kidney, and diffuse cystic lung diseases. Definitive diagnosis of LAM is based on a high level of clinical suspicion on presentation supported by pathological findings or by a distinct feature, such as a history of TSC, AMLs in the kidney, chylothorax, or chylous ascites. Vascular endothelial growth factor-D (VEGF-D) in serum is a noninvasive and reliable diagnostic biomarker. In experienced centers, trans-bronchial lung biopsy (TBLB) provides a convenient and safe way to obtain lung specimens for diagnostic purposes. An effective treatment for LAM is now available, namely using a mechanistic target of rapamycin (mTOR) inhibitor such as sirolimus. Efficacy of sirolimus has been confirmed in clinical trials. Research in other molecular-targeted therapies is under investigation. A previously little-known rare disease with no cure is now better understood with regards to its pathogenesis, diagnosis, and management. In this review, current knowledge in diagnosis and differential diagnosis of LAM will be discussed, followed by the discussion of therapy with mTOR inhibitors.

Towards personalised therapy for lymphangioleiomyomatosis: lessons from cancer

Lymphangioleiomyomatosis (LAM) is a rare cystic, destructive lung disease occurring almost exclusively in females. Bi-allelic inactivating tuberous sclerosis complex (TSC) gene mutations occur in LAM cells, resulting in activation of the mTORC1 pathway. Pivotal clinical trials have demonstrated that inhibition of mTORC1 with sirolimus can induce a partial response of TSC-associated tumours and decrease the rate of lung function decline in females with LAM. Many parallels have been identified between LAM pathogenesis and neoplasia. Here, we highlight three key nodes through which advances in cancer therapy can streamline future innovation in clinical LAM research with parallels to breast and prostate cancer. These include: 1) hormonally targeted therapies to achieve true disease-free complete remissions; 2) the use of vascular endothelial growth factor-D and other plasma biomarkers to streamline early-phase clinical trials; and 3) the utilisation of histological and molecular features of biopsy material to enable patient stratification and personalised therapies.

Prognostic Value of Lymphocyte Vascular Density and E-Cadherin in Inflammatory Breast Cancer

Background: We recently evaluated four laboratory assays, vascular endothelial growth factor D (VEGF-D), E-cadherin, lymphatic vessel density (LVD) measured by podoplanin, and intra-lymphatic tumor emboli (ILTE), which showed notable differences between inflammatory breast cancer (IBC) and non-inflammatory locally advanced breast cancer (LABC). In this study we investigated the potential of the three most quantitatively measured markers, E-cadherin, LVD and VEGF-D, to predict survival in the IBC patients. Materials and Methods: This study involved the 100 cases identified in the Inflammatory Breast Cancer Registry (IBCR) whose tumors were previously evaluated for the four assays noted above. Living patients were recontacted and survival data were available for up to 17 years. Overall survival (OS) was analyzed through the Kaplan-Meier method stratified by E-cadherin, LVD, VEGF-D, and response to chemotherapy. The differences in OS curves were compared using the log-rank test. Results: The median OS for patients with high LVD was 6.63 years (95% CI: 4.06 to 10.14), compared to median at 10 years not reached in those with low LVD (p = 0.03). There was a trend towards a longer median OS in patients with high E-cadherin (10.14, 95% CI: 6.63 to 11.67), compared with those with low E-cadherin (6.26, 95% CI: 3.42 to undeterminable). VEGF-D levels showed no correlation with survival. Conclusion: Low LVD significantly predicts better survival. High E-cadherin expression, as with non-IBC breast cancer and several other malignancies, tends to be associated with a better prognosis.

Patients with rheumatoid arthritis in clinical remission and ultrasound-defined active synovitis exhibit higher disease activity and increased serum levels of angiogenic biomarkers

IntroductionThe aim of this study was to identify and characterize subclinical synovitis in patients with rheumatoid arthritis (RA) in clinical remission using power Doppler ultrasound (PDUS) and serum levels of biomarkers of inflammation and/or angiogenesis.MethodsWe selected patients with RA in clinical remission defined as a Disease activity score of 28 joints (DAS28)-erythrocyte sedimentation rate (ESR) <2.6 for more than six months tested by two independent rheumatologists. Clinical, epidemiological, demographic and serological data were analyzed. PDUS of knees and hands was performed by a sonographer. Synovial hypertrophy (SH) and PDUS signal were scored (grades 0 to 3). SH ≥2 and a PDUS signal was classified as active synovitis. Serum levels of biomarkers of inflammation/angiogenesis were determined by Quantibody® Human Array.ResultsThis study included 55 patients, of whom 25 (45.4%) met criteria for ultrasound-defined active synovitis. Patients with active synovitis had higher DAS28-C reactive protein (P = 0.023), DAS28-ESR (P = 0.06), simplified disease activity score, SDAI (P = 0.064), and only 12% were taking oral glucocorticoids (≤5 mg/day) compared with 40% of patients without active synovitis (P = 0.044). Patients with synovitis also had significantly higher serum levels of the angiogenic biomarkers angiopoietin-2 (P = 0.038), vascular endothelial growth factor-D (P = 0.018), placental growth factor (P = 0.043), stromal cell-derived factor-1 (P = 0.035), matrix metallopeptidase-2 (P = 0.027) and basic fibroblast growth factor (bFGF) (P = 0.007), but not of pro-inflammatory cytokines.In the multivariate logistic regression model used to explore prognostic biomarkers for active synovitis, serum levels of bFGF, DAS28-ESR and not receiving glucocorticoids were the best predictors of active synovitis. The predictive indexes provided by the model were specificity 73.3%, sensitivity 72%, and area under the curve in receiver operating characteristic 81.5% (95% CI: 70.1% to 92.8%).ConclusionsNearly half of the patients with RA in clinical remission had ultrasound-defined active synovitis, higher disease activity and less frequent oral glucocorticoid consumption than patients without active synovitis. This clinical situation was associated with a specific biological profile characterized by an excess of angiogenic mediators rather than persistent proinflammatory cytokine responses.

Correlation between vascular endothelial growth factors and their receptor with lymph node metastasis of lung cancer

Objective To investigate the expression of vascular endothelial growth factor-C (VEGF-C),VEGF-D and VEGF receptor-3 (VEGFR-3) in non-small cell lung cancer (NSCLC) and their correlation with lymph node metastasis.Methods By using fluorescence quantitative RT-PCR,the expression of VEGF-C,VEGF-D and VEGFR-3 was detected in 96 patients with NSCLC.Results There was a significant correlation betwwen the positive expression of VEGF-C,VEGF-D and VEGFR-3 and lymph node metastasis and TNM stage (P ＜ 0.05).The expression levels of VEGF-C,VEGF-D and VEGFR-3 mRNA in lung cancer tissues were significantly higher than in normal tissues (P ＜0.01).in NSCLC,there was a positive correlation among VEGF-C,VEGF-D and VEGFR-3 mRNA expression.Conclusion VEGF-C,VEGF-D and VEGF-3 play an important role in the occurrence,development and lymph node metastasis of NSCLC. Key words: Lung cancer; Vascular endothelial growth factor; Lymph node; Metastasis

Expression of vascular endothelial growth factor D in human esophageal squamous cell carcinoma tissue and its significance

To investigate the expression of vascular endothelial growth factor D (VEGF-D) in human esophageal squamous cell carcinoma (ESCC) and its significance. The expression of VEGF-C mRNA in tumor tissues and non-cancer tissues from 39 ESCC patients in our hospital from March 2009 to February 2010 was detected by in situ hybridization (ISH) method. The expression of D2-40 was detected by immunohistochemistry,and microlymphatic vessel density (MLVD) was determined by lymphatic endothelial specific marker D2-40. The associations of VEGF-C mRNA expression with clinical data and MLVD were analyzed. Positive ISH VEGF-D mRNA was observed in tumor tissue samples of 22 cases (56.4%, 22/39) and non-cancer tissue sample of 1 case (2.6%, 1/39), whose difference was statistically significant (P<0.05). The expression of VEGF-D mRNA in ESCC was significantly associated with lymph node metastasis [92.9% (13/14) vs. 36.0% (9/25), P<0.05] and MLVD [(8.20±1.22) vs. (5.31±0.97), P<0.01], but not significantly associated with age, sex, pathological grade and depth of infiltration. VEGF-D can promote lymphatic metastasis of ESSC by induction of lymphangiogenesis.

Inflammation induces neuro-lymphatic protein expression in multiple sclerosis brain neurovasculature

BackgroundMultiple sclerosis (MS) is associated with ectopic lymphoid follicle formation. Podoplanin+ (lymphatic marker) T helper17 (Th17) cells and B cell aggregates have been implicated in the formation of tertiary lymphoid organs (TLOs) in MS and experimental autoimmune encephalitis (EAE). Since podoplanin expressed by Th17 cells in MS brains is also expressed by lymphatic endothelium, we investigated whether the pathophysiology of MS involves inductions of lymphatic proteins in the inflamed neurovasculature.MethodsWe assessed the protein levels of lymphatic vessel endothelial hyaluronan receptor and podoplanin, which are specific to the lymphatic system and prospero-homeobox protein-1, angiopoietin-2, vascular endothelial growth factor-D, vascular endothelial growth factor receptor-3, which are expressed by both lymphatic endothelium and neurons. Levels of these proteins were measured in postmortem brains and sera from MS patients, in the myelin proteolipid protein (PLP)-induced EAE and Theiler’s murine encephalomyelitis virus (TMEV) induced demyelinating disease (TMEV-IDD) mouse models and in cell culture models of inflamed neurovasculature.Results and conclusionsIntense staining for LYVE-1 was found in neurons of a subset of MS patients using immunohistochemical approaches. The lymphatic protein, podoplanin, was highly expressed in perivascular inflammatory lesions indicating signaling cross-talks between inflamed brain vasculature and lymphatic proteins in MS. The profiles of these proteins in MS patient sera discriminated between relapsing remitting MS from secondary progressive MS and normal patients. The in vivo findings were confirmed in the in vitro cell culture models of neuroinflammation.

Role of serum vascular endothelial growth factor D in discrimination of patients with polycystic lung diseases

Polycystic lung diseases (PLDs) include numerous rare diseases including lymphangioleiomyomatosis (LAM), pulmonary Langerhans cell histiocytosis (PLCH), and lymphocytic interstitial pneumonia. In these cases, diagnosis is based on a histological examination of open lung biopsy samples; however, it is not always possible to perform this procedure. Serum markers characteristic for a given entity are still being sought. The aim of the study was to determine the usefulness of assessing serum vascular endothelial growth factor D (VEGF‑D) concentration in the differential diagnosis of LAM and other PLDs (OPLDs). Serum VEGF‑D levels were measured by an enzyme‑linked immunosorbent assay in 75 patients with PLDs including 29 women with LAM and 46 patients with OPLDs (28 women and 18 men). Serum VEGF‑D levels were significantly higher in patients with LAM (median, 1557 pg/ml; interquartile range [IQR], 636-2593 pg/ml) than in all patients with OPLDs (median, 292 pg/ml; IQR, 233-405 pg/ml, P <0.0001) or than in women with OPLDs (median, 344 pg/ml; IQR, 243-452 pg/ml, P <0.0001). The serum VEGF‑D level exceeding 468 pg/ml identified LAM patients with the specificity of 90% and sensitivity of 87% (area under the curve of 0.908; 95% confidence interval, 0.820-0.996). In none of the patients with OPLDs serum VEGF‑D concentrations exceeded 800 pg/ml. An increased serum VEGF‑D level is a highly specific biomarker useful in a differential diagnosis of LAM and OPLDs.

Vascular Endothelial Growth Factor-D–Mediated Blockade of Regulatory T Cells within Tumors Is Induced by Hematopoietic Stem Cell Transplantation

Lymphopenia-induced homeostatic proliferation of T cells after autologous hematopoietic stem cell transplantation (HSCT) skews the T cell repertoire by engaging tumor-associated Ags, leading to an induction of antitumor immunity. However, how HSCT alters the immunosuppressive microenvironment in the tumors is unknown. In this study, we first analyzed the kinetics of regulatory T cells (Tregs) in the tumors after syngeneic HSCT. Unexpectedly, the frequency of CD4⁺ cells expressing Foxp3 was increased in the spleens, whereas the frequency was clearly decreased in the tumors after HSCT. The origin of reconstituted CD4⁺ and Foxp3⁺ cells in the tumors was mainly from the expansion of transferred splenic T cells. Then, to examine the mechanism of Treg suppression after HSCT, we isolated CD11c⁺ cells from tumors. A large amount of Treg-inhibitory cytokine IL-6 was secreted from the CD11c⁺ cells in the tumors, but not in the spleens in the recipient mice. Furthermore, to understand what factor affects the activity of CD11c⁺ cells in the tumors after HSCT, we analyzed the expression of various cytokines/chemokines with mouse cytokine Ab arrays, and noticed that VEGF-D concentration was increased in the tumors in the early period after HSCT. The CD11c⁺ cells produced IL-6 in response to VEGF-D stimulation, and an administration of VEGF receptor-3 neutralizing Ab significantly suppressed the production of IL-6 from CD11c⁺ cells accompanied with the increase of Tregs in the tumors of HSCT recipients. Autologous HSCT creates an environment that strongly supports the enhancement of antitumor immunity in reconstituted lymphopenic recipients through the suppression of Tregs.

Vascular Endothelial Growth Factor-d Modulates Caliber and Function of Initial Lymphatics in the Dermis

The lymphatic vasculature is important for skin biology as it maintains dermal fluid homeostasis. However, the molecular determinants of the form and function of the lymphatic vasculature in skin are poorly understood. Here, we explore the role of vascular endothelial growth factor-d (Vegf-d), a lymphangiogenic glycoprotein, in determining the form and function of the dermal lymphatic network, using Vegf-d-deficient mice. Initial lymphatic vessels in adult Vegf-d-deficient mice were significantly smaller than wild-type but collecting lymphatics were unaltered. The uptake/transport of dextran in initial lymphatics of Vegf-d-deficient mice was far less efficient, indicating compromised function of these vessels. The role of Vegf-d in modulating initial lymphatics was further supported by delivery of Vegf-d in skin of wild-type mice, which promoted enlargement of these vessels. Vegf-d-deficient mice were subjected to cutaneous wounding to challenge lymphatic function: the resulting wound epithelium was highly edematous and thicker, reflecting inadequate lymphatic drainage. Unexpectedly, myofibroblasts were more abundant in Vegf-d-deficient wounds leading to faster wound closure, but resorption of granulation tissue was compromised suggesting poorer-quality healing. Our findings demonstrate that Vegf-d deficiency alters the caliber of initial lymphatics in the dermis leading to reduced functional capacity.

Pressure and inflammatory stimulation induced increase of cadherin-11 is mediated by PI3K/Akt pathway in synovial fibroblasts from temporomandibular joint

The goal of the study was to investigate the expression of cadherin-11 in synovial fibroblasts (SFs) under mechanical or inflammatory stimuli, and its potential relationship with PI3K/Akt signaling pathway. SFs separated from rat temporomandibular joint (TMJ) were treated with hydrostatic pressures (HP) of 30, 60, 90, and 120kPa, as well as tumor necrosis factor-α (TNF-α) for 12, 24, 48, and 72h. The location of cadherin-11 was observed by immunofluorescence microscopy, and its expression was detected by real-time PCR and Western blot. We also studied the activation of PI3K/Akt signaling pathway in SFs with HP or TNF-α stimulation. The results showed that increased expression of cadherin-11 could be found in the cell-cell contact site of SFs in response to HP and inflammatory stimulation. The mRNA and protein expression of cadherin-11 was positively correlated with the intensity of HP and the duration time of TNF-α treatment. Increased expression of vascular endothelial growth factor-D (VEGF-D) and activation of Akt were also found. Treatment with PI3K inhibitor LY294002 attenuated the pressure or inflammatory cytokine induction increases of cadherin-11, VEGF-D, and FGF-2 both in mRNA and protein levels. These findings suggest that cadherin-11 may play important roles in SFs following exposure to mechanical loading and inflammatory stimulation. In addition, PI3K/Akt pathway was associated with pressure or inflammation-induced cadherin-11 expression, which may involve in the pathogenesis of temporomandibular diseases.