Real-world treatment patterns and clinical outcomes in patients with stage III NSCLC in Korea: The KINDLE study.

OBJECTIVE: KINDLE-Korea is part of a real-world KINDLE study that aimed to characterize the treatment patterns and clinical outcomes of patients with stage III non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: The KINDLE was an international real-world study that explores patient and disease characteristics, treatment patterns, and survival outcomes. The KINDLE-Korea included stage III NSCLC patients diagnosed between January 2013 and December 2017. RESULTS: A total of 461 patients were enrolled. The median age was 66 years (range: 24-87). Most patients were men (75.7%) with a history of smoking (74.0%), stage IIIA NSCLC (69.2%), and unresectable disease (52.9%). A total of 24.3% had activating EGFR mutation and 62.2% were positive for PDL1 expression. Broadly categorized, 44.6% of the patients received chemoradiation (CRT)-based therapy, 35.1% underwent surgery, and 20.3% received palliative therapies as initial treatment. The most commonly adopted approaches for patients with stage IIIA and IIIB disease were surgery and CRT, respectively. The median PFS was 15.2 months and OS was 66.7 months. Age >65 years, adenocarcinoma histology, and surgery as the initial treatment were significantly associated with longer OS. CONCLUSION: This study revealed the heterogeneity of treatment patterns and survival outcomes in patients with stage III NSCLC before durvalumab consolidation came into clinical practice. There is an unmet need for patients who are not eligible for surgery as an initial therapy. Novel therapeutic approaches are highly warranted to improve clinical outcomes.

Real-world clinical practice and outcomes in treating stage III non-small cell lung cancer: KINDLE-Asia subset.

Introduction: Stage III non-small cell lung cancer (NSCLC) is a heterogeneous disease requiring multimodal treatment approaches. KINDLE-Asia, as part of a real world global study, evaluated treatment patterns and associated survival outcomes in stage III NSCLC in Asia. Methods: Retrospective data from 57 centers in patients with stage III NSCLC diagnosed between January 2013 and December 2017 were analyzed. Median progression free survival (mPFS) and median overall survival (mOS) estimates with two sided 95% confidence interval (CI) were determined by applying the Kaplan-Meier survival analysis. Results: Of the total 1874 patients (median age: 63.0 years [24 to 92]) enrolled in the Asia subset, 74.8% were men, 54.7% had stage IIIA disease, 55.7% had adenocarcinoma, 34.3% had epidermal growth factor receptor mutations (EGFRm) and 50.3% had programmed death-ligand 1 (PD-L1) expression (i.e. PD-L1 ≥1%). Of the 31 treatment approaches as initial therapy, concurrent chemoradiotherapy (CRT) was the most frequent (29.3%), followed by chemotherapy (14.8%), sequential CRT (9.5%), and radiotherapy (8.5%). Targeted therapy alone was used in 81 patients of the overall population. For the Asia cohort, the mPFS and mOS were 12.8 months (95% CI, 12.2-13.7) and 42.3 months (95% CI, 38.1-46.8), respectively. Stage IIIA disease, Eastern Cooperative Oncology Group ≤1, age ≤65 years, adenocarcinoma histology and surgery/concurrent CRT as initial therapy correlated with better mOS (p < 0.05). Conclusions: The results demonstrate diverse treatment patterns and survival outcomes in the Asian region. The high prevalence of EGFRm and PD-L1 expression in stage III NSCLC in Asia suggests the need for expanding access to molecular testing for guiding treatment strategies with tyrosine kinase inhibitors and immunotherapies in this region.

Real-world KINDLE-Latin America subset data on treatment patterns and clinical outcomes in patients with stage III non-small-cell lung cancer.

INTRODUCTION: Stage III non-small-cell lung cancer (NSCLC) management is challenging given the heterogeneous nature of the disease. The LATAM subset of the real-world, global KINDLE study reported the treatment patterns and clinical outcomes for LATAM from the pre-immuno-oncology era. METHODS: The study was conducted in seven countries (Argentina, Chile, Colombia, Dominican Republic, Mexico, Peru and Uruguay) in stage III NSCLC (American Joint Committee on Cancer, 7th edition) diagnosed between January 2013 and December 2017. Retrospective data from patients' medical records (index date to the end of follow-up) were collected. Summary statistics, Kaplan-Meier survival estimates and a two-sided 95% confidence interval (CI) were provided. Cox proportional hazard model was used for univariate and multi-variate analyses. RESULTS: A total of 231 patients was enrolled, the median age was 65.0 years (range 21.0-89.0), 60.6% were males, 76.6% had smoking history, 64.0% had adenocarcinoma and 28.7% underwent curative resection. Multiple treatment regimens (>25) were used; chemotherapy alone was the most common (24.8%). The overall median progression-free survival (mPFS) and median overall survival (mOS) were 14.8 months (95% CI, 12.1-18.6) and 48.6 months (95% CI, 34.7 to not calculable). Significantly better mPFS and mOS were observed for stage IIIA with curative surgery and resectable tumours and stage IIIB with an Eastern Cooperative Oncology Group score of 0/1, female gender, resectable tumours, adenocarcinoma and curative surgery (p < 0.05). CONCLUSION: Results show diversity in treatment practices and the corresponding clinical outcomes in stage III NSCLC. There is a need to streamline treatment selection and sequencing to decrease relapse rates after initial therapy.

Real-world global data on targeting epidermal growth factor receptor mutations in stage III non-small-cell lung cancer: the results of the KINDLE study.

Background: Tyrosine kinase inhibitors (TKIs) are the standard of care for resectable and metastatic non-small-cell lung cancer (NSCLC) harbouring epidermal growth factor receptor (EGFR) mutations (EGFRm). We describe the real-world practice of EGFRm testing, prevalence, treatment and outcomes in EGFRm stage III NSCLC from a multi-country, observational study. Methods: The KINDLE study retrospectively captured diagnostic information, treatments and survival outcomes in patients with stage III NSCLC from January 2013 to December 2017. Baseline characteristics and treatments were described and real-world outcomes from initial therapy were analysed using Kaplan-Meier methods. Results: A total of 3151 patients were enrolled across three regions: Asia (n = 1874), Middle East and North Africa (MENA) (n = 1046) and Latin America (LA) (n = 231). Of these, 1114 patients (35%) were tested for EGFRm (46% in Asia, 17% in MENA and 32% in LA) and EGFRm was detected in 32% of tested patients (34.3% in Asia, 20.0% in MENA and 28.4% in LA). In a multi-variate analysis, overall EGFRm patients treated with EGFR-TKI monotherapy as initial treatment, without any irradiation, had twice the risk of dying (hazard ratio: 1.983, 95% confidence interval: 1.079-3.643; p = 0.027) versus any other treatment. Finally, unresectable patients with EGFRm NSCLC who received concurrent chemoradiotherapy (cCRT) as initial therapy had longer overall survival (OS) compared with their counterparts who only received TKI monotherapy without any irradiation (48 months versus 24 months; p < 0.001). Conclusion: The KINDLE study showed that a minority of stage III NSCLC patients were tested for EGFRm. Patients with EGFRm with unresectable NSCLC had similar outcomes from cCRT as initial therapy compared with EGFR wild type with a trend in OS favouring the EGFRm group. Outcomes with EGFR-TKI monotherapy as initial therapy, without any irradiation, were worse. The ongoing LAURA study (NCT03521154) will help define the role of EGFR-TKIs in EGFRm stage III NSCLC treated with cCRT. Trial Registration: NCT03725475.

Real-World Treatment Patterns and Clinical Outcomes in Patients With Stage III Non-Small-Cell Lung Cancer: Results of KINDLE-Vietnam Cohort.

Objective: KINDLE-Vietnam was a part of a real-world KINDLE study with an aim to characterise treatment patterns and clinical outcomes of patients with stage III non-small cell lung cancer (NSCLC). Materials and Methods: Retrospective data from patients diagnosed with stage III NSCLC (American Joint Committee on Cancer, 7th edition) between January 2013 and December 2017 with at least 9 months of follow-up were collected from 2 centres in Vietnam. Descriptive statistics were used to summarise demographics, disease characteristics and treatment modalities. Kaplan-Meier methodology evaluated survival estimates; 2-sided 95% confidence intervals (CIs) were computed. Inferential statistics were used to correlate clinical and treatment variables with median progression-free survival (mPFS) and median overall survival (mOS). Results: A total of 150 patients (median age: 60 years [range 26-82]) were enrolled; 75.3% were male, 62.0% had smoking history, 56.4% had stage IIIB disease and 62.5% had adenocarcinoma. The majority of the cases (97.3%) were not discussed at a multidisciplinary team meeting. Overall, chemotherapy alone (43.3%), radiotherapy alone (17.0%), sequential chemoradiation (13.5%) and concurrent chemoradiation (12.8%) were preferred as initial therapy. Surgery-based treatment was administered in limited patients (stage IIIA, 10%; stage IIIB, 1.3%). Palliative therapy was the most commonly administered treatment upon relapse in the second-and third-line setting. The mPFS and mOS for the Vietnam cohort were 8.7 months (95% CI, 7.59-9.72) and 25.7 months (95% CI, 19.98-42.61), respectively. The mPFS and mOS for stage IIIA were 11.9 months (95% CI, 8.64-14.95) and 28.2 months (95% CI, 24.15-not-calculable) and for stage IIIB were 7.8 months (95% CI, 6.64-8.71) and 20.0 months (95% CI, 13.01-42.61). Conclusions: KINDLE-Vietnam offers insights into the clinical findings of stage III NSCLC. There is a high unmet need for identifying patients in the early stages of NSCLC. Strategies for improving clinical outcomes in this patient population include physician education, multidisciplinary management and catering to increased access to novel agents like immunotherapy and targeted therapy.

Real-World Treatment Patterns and Clinical Outcomes in Patients With Stage III NSCLC: Results of KINDLE, a Multicountry Observational Study.

INTRODUCTION: Stage III NSCLC is a heterogeneous disease requiring a multimodal management approach. We conducted a real-world, global study to characterize patients, treatment patterns, and their associated clinical outcomes for stage III NSCLC. METHODS: KINDLE was a retrospective study in patients with stage III NSCLC (American Joint Committee on Cancer, seventh edition) diagnosed between January 2013 and December 2017, with at least 9 months of documented follow-up since index diagnosis. In addition to descriptive statistics, Kaplan-Meier methodology evaluated survival estimates; two-sided 95% confidence interval was computed. Cox proportional hazards model was used for univariate and multivariate analyses. RESULTS: A total of 3151 patients from more than 100 centers across 19 countries from Asia, Middle East, Africa, and Latin America were enrolled. Median age was 63.0 years (range: 21.0-92.0); 76.5% were males, 69.2% had a smoking history, 53.7% had adenocarcinoma, and 21.4% underwent curative resection. Of greater than 25 treatment regimens, concurrent chemoradiotherapy was the most common (29.4%). The overall median progression-free survival (95% confidence interval) and median overall survival (mOS) were 12.5 months (12.06-13.14) and 34.9 months (32.00-38.01), respectively. Significant associations (p < 0.05) were observed for median progression-free survival and mOS with respect to sex, region, smoking status, stage, histology, and Eastern Cooperative Oncology Group status. In univariate and multivariate analyses, younger age, stage IIIA, better Eastern Cooperative Oncology Group status, concurrent chemoradiotherapy, and surgery as initial therapy predicted better mOS. CONCLUSIONS: KINDLE reveals the diversity in treatment practices and outcomes in stage III NSCLC in a real-world setting in the preimmuno-oncology era. There is a high unmet medical need, necessitating novel approaches to optimize outcomes.

An important role of the SDF-1/CXCR4 axis in chronic skin inflammation.

Inflammatory angiogenesis and vascular remodeling play key roles in the chronic inflammatory skin disease psoriasis, but little is known about the molecular mediators of vascular activation. Based on the reported elevated mRNA levels of the angiogenic chemokine stromal cell-derived factor-1 (SDF-1) and its receptor CXCR4 in psoriasis, we investigated the relevance of the SDF-1/CXCR4 axis in two experimental models of chronic psoriasis-like skin inflammation. The cutaneous expression of both SDF-1 and CXCR4 was upregulated in the inflamed skin of K14-VEGF-A transgenic mice and in imiquimod-induced skin inflammation, with expression of CXCR4 by blood vessels and macrophages. Treatment with the CXCR4 antagonist AMD3100 potently inhibited skin inflammation in both models, associated with reduced inflammatory angiogenesis and inflammatory cell accumulation, including dermal CD4+ cells and intraepidermal CD8+ T cells. Similar anti-inflammatory effects were seen after treatment with a neutralizing anti-SDF-1 antibody. In vitro, inhibition of CXCR4 blocked SDF-1-induced chemotaxis of CD11b+ splenocytes, in agreement with the reduced number of macrophages after in vivo CXCR4 blockade. Our results reveal an important role of the SDF-1/CXCR4 axis in skin inflammation and inflammatory angiogenesis, and they indicate that inhibition of the SDF-1/CXCR4 axis might serve as a novel therapeutic strategy for chronic inflammatory skin diseases.

Increased permeability of cutaneous lymphatic capillaries and enhanced blood flow in psoriatic plaques.

INTRODUCTION: Morphological abnormalities of microvessels are described in psoriasis. However, there are conflicting data as to whether their function is also altered. OBJECTIVE: Our aim was to study the morphology and function of the lymphatic capillaries of psoriatic skin. METHODS: Morphology and permeability of initial lymphatics were studied by microlymphography and densitometry in 20 patients. Perfusion was studied by laser Doppler fluxmetry. RESULTS: Permeability of lymphatics in plaques was increased by 7.6% compared to unafflicted skin (p < 0.001). Lymphatic vessel density and the extension of dye in lymphatic networks were not significantly different between involved and uninvolved areas. Both sites showed a wide range of diameters of lymphatics. The median laser Doppler flux in plaques was increased by 144% (91-380%) compared to unaffected skin (p < 0.001). CONCLUSIONS: Increased permeability of lymphatics and increased blood flow was demonstrated in vivo in psoriatic skin lesions. These findings may reflect the local inflammatory process and may be used as markers when studying new therapeutic approaches for psoriasis.

Non-invasive dynamic near-infrared imaging and quantification of vascular leakage in vivo.

Preclinical vascular research has been hindered by a lack of methods that can sensitively image and quantify vascular perfusion and leakage in vivo. In this study, we have developed dynamic near-infrared imaging methods to repeatedly visualize and quantify vascular leakage in mouse skin in vivo, and we have applied these methods to transgenic mice with overexpression of vascular endothelial growth factors VEGF-A or -C. Near-infrared dye conjugates were developed to identify a suitable vascular tracer that had a prolonged circulation lifetime and slow leakage into normal tissue after intravenous injection. Dynamic simultaneous imaging of ear skin and a large blood vessel in the leg enabled determination of the intravascular signal (blood volume fraction) from the tissue signal shortly after injection and quantifications of vascular leakage into the extravascular tissue over time. This method allowed for the sensitive detection of increased blood vascularity and leakage rates in K14-VEGF-A transgenic mice and also reliably measured inflammation-induced changes of vascularity and leakage over time in the same mice. Measurements after injection of recombinant VEGF-A surprisingly revealed increased blood vascular leakage and lymphatic clearance in K14-VEGF-C transgenic mice which have an expanded cutaneous lymphatic vessel network, potentially indicating unanticipated effects of lymphatic drainage on vascular leakage. Increased vascular leakage was also detected in subcutaneous tumors, confirming that the method can also be applied to deeper tissues. This new imaging method might facilitate longitudinal investigations of the in vivo effects of drug candidates, including angiogenesis inhibitors, in preclinical disease models.

Endocan is upregulated on tumor vessels in invasive bladder cancer where it mediates VEGF-A-induced angiogenesis.

Tumor-associated blood vessels differ from normal vessels and proteins present only on tumor vessels may serve as biomarkers or targets for antiangiogenic therapy in cancer. Comparing the transcriptional profiles of blood vascular endothelium from human invasive bladder cancer with normal bladder tissue, we found that the endothelial cell-specific molecule endocan (ESM1) was highly elevated on tumor vessels. Endocan was associated with filopodia of angiogenic endothelial tip cells in invasive bladder cancer. Notably, endocan expression on tumor vessels correlated strongly with staging and invasiveness, predicting a shorter recurrence-free survival time in noninvasive bladder cancers. Both endocan and VEGF-A levels were higher in plasma of patients with invasive bladder cancer than healthy individuals. Mechanistic investigations in cultured blood vascular endothelial cells or transgenic mice revealed that endocan expression was stimulated by VEGF-A through the phosphorylation and activation of VEGFR-2, which was required to promote cell migration and tube formation by VEGF-A. Taken together, our findings suggest that disrupting endocan interaction with VEGFR-2 or VEGF-A could offer a novel rational strategy to inhibit tumor angiogenesis. Furthermore, they suggest that endocan might serve as a useful biomarker to monitor disease progression and the efficacy of VEGF-A-targeting therapies in patients with bladder cancer.

The cutaneous vascular system in chronic skin inflammation.

The blood and lymphatic vasculature have an important role in skin homeostasis. Angiogenesis and lymphangiogenesis-the growth of new vessels from existing ones-have received tremendous interest because of their role in promoting cancer spread. However, there is increasing evidence that both vessel types also have a major role in acute and chronic inflammatory disorders. Vessels change their phenotype during inflammation (vascular remodeling). In inflamed skin, vascular remodeling consists of a hyperpermeable, enlarged network of vessels with increased blood flow, and influx of inflammatory cells. During chronic inflammation, the activated endothelium expresses adhesion molecules, cytokines, and other molecules that lead to leukocyte rolling, attachment, and migration into the skin. Recent studies reveal that inhibition of blood vessel activation exerts potent anti-inflammatory properties. Thus, anti-angiogenic drugs might be used to treat inflammatory conditions. In particular, topical application of anti-angiogenic drugs might be ideally suited to circumvent the adverse effects of systemic therapy with angiogenesis inhibitors. Our recent results indicate that stimulation of lymphatic vessel growth and function unexpectedly represents a new approach for treating chronic inflammatory disorders.

An important role of lymphatic vessel activation in limiting acute inflammation.

In contrast to the established role of blood vessel remodeling in inflammation, the biologic function of the lymphatic vasculature in acute inflammation has remained less explored. We studied 2 established models of acute cutaneous inflammation, namely, oxazolone-induced delayed-type hypersensitivity reactions and ultraviolet B irradiation, in keratin 14-vascular endothelial growth factor (VEGF)-C and keratin 14-VEGF-D transgenic mice. These mice have an expanded network of cutaneous lymphatic vessels. Transgenic delivery of the lymphangiogenic factors VEGF-C and the VEGFR-3 specific ligand mouse VEGF-D significantly limited acute skin inflammation in both experimental models, with a strong reduction of dermal edema. Expression of VEGFR-3 by lymphatic endothelium was strongly down-regulated at the mRNA and protein level in acutely inflamed skin, and no VEGFR-3 expression was detectable on inflamed blood vessels and dermal macrophages. There was no major change of the inflammatory cell infiltrate or the composition of the inflammatory cytokine milieu in the inflamed skin of VEGF-C or VEGF-D transgenic mice. However, the increased network of lymphatic vessels in these mice significantly enhanced lymphatic drainage from the ear skin. These results provide evidence that specific lymphatic vessel activation limits acute skin inflammation via promotion of lymph flow from the skin and reduction of edema formation.

Stimulation of lymphangiogenesis via VEGFR-3 inhibits chronic skin inflammation.

The role of lymphangiogenesis in inflammation has remained unclear. To investigate the role of lymphatic versus blood vasculature in chronic skin inflammation, we inhibited vascular endothelial growth factor (VEGF) receptor (VEGFR) signaling by function-blocking antibodies in the established keratin 14 (K14)-VEGF-A transgenic (Tg) mouse model of chronic cutaneous inflammation. Although treatment with an anti-VEGFR-2 antibody inhibited skin inflammation, epidermal hyperplasia, inflammatory infiltration, and angiogenesis, systemic inhibition of VEGFR-3, surprisingly, increased inflammatory edema formation and inflammatory cell accumulation despite inhibition of lymphangiogenesis. Importantly, chronic Tg delivery of the lymphangiogenic factor VEGF-C to the skin of K14-VEGF-A mice completely inhibited development of chronic skin inflammation, epidermal hyperplasia and abnormal differentiation, and accumulation of CD8 T cells. Similar results were found after Tg delivery of mouse VEGF-D that only activates VEGFR-3 but not VEGFR-2. Moreover, intracutaneous injection of recombinant VEGF-C156S, which only activates VEGFR-3, significantly reduced inflammation. Although lymphatic drainage was inhibited in chronic skin inflammation, it was enhanced by Tg VEGF-C delivery. Together, these results reveal an unanticipated active role of lymphatic vessels in controlling chronic inflammation. Stimulation of functional lymphangiogenesis via VEGFR-3, in addition to antiangiogenic therapy, might therefore serve as a novel strategy to treat chronic inflammatory disorders of the skin and possibly also other organs.

Podoplanin-Fc reduces lymphatic vessel formation in vitro and in vivo and causes disseminated intravascular coagulation when transgenically expressed in the skin.

Podoplanin is a small transmembrane protein required for development and function of the lymphatic vascular system. To investigate the effects of interfering with its function, we produced an Fc fusion protein of its ectodomain. We found that podoplanin-Fc inhibited several functions of cultured lymphatic endothelial cells and also specifically suppressed lymphatic vessel growth, but not blood vessel growth, in mouse embryoid bodies in vitro and in mouse corneas in vivo. Using a keratin 14 expression cassette, we created transgenic mice that overexpressed podoplanin-Fc in the skin. No obvious outward phenotype was identified in these mice, but surprisingly, podoplanin-Fc-although produced specifically in the skin-entered the blood circulation and induced disseminated intravascular coagulation, characterized by microthrombi in most organs and by thrombocytopenia, occasionally leading to fatal hemorrhage. These findings reveal an important role of podoplanin in lymphatic vessel formation and indicate the potential of podoplanin-Fc as an inhibitor of lymphangiogenesis. These results also demonstrate the ability of podoplanin to induce platelet aggregation in vivo, which likely represents a major function of lymphatic endothelium. Finally, keratin 14 podoplanin-Fc mice represent a novel genetic animal model of disseminated intravascular coagulation.

Systemic anti-VEGF treatment strongly reduces skin inflammation in a mouse model of psoriasis.

Although(,) vascular remodeling is a hallmark of many chronic inflammatory disorders such as rheumatoid arthritis, inflammatory bowel disease, and psoriasis, anti-vascular strategies to treat these conditions have received little attention to date. We investigated the anti-inflammatory activity of systemic blockade of VEGF-A by the inhibitory monoclonal antibody G6-31, employing a therapeutic trial in a mouse model of psoriasis. Simultaneous deletion of JunB and c-Jun (DKO*) in the epidermis of adult mice leads to a psoriasis-like phenotype with hyper- and parakeratosis and increased subepidermal vascularization. Moreover, an inflammatory infiltrate and elevated levels of cytokines/chemokines including TNFalpha, IL-1alpha/beta, IL-6, and the innate immune mediators IL-22, IL-23, IL-23R, and IL-12p40 are detected. Here we show that anti-VEGF antibody treatment of mice already displaying disease symptoms resulted in an overall improvement of the psoriatic lesions leading to a reduction in the number of blood vessels and a significant decrease in the size of dermal blood and lymphatic vessels. Importantly, anti-VEGF-treated mice showed a pronounced reduction of inflammatory cells within the dermis and a normalization of epidermal differentiation. These results demonstrate that systemic blockade of VEGF by an inhibitory antibody might be used to treat patients who have inflammatory skin disorders such as psoriasis.

Activation of the VEGFR-3 pathway by VEGF-C attenuates UVB-induced edema formation and skin inflammation by promoting lymphangiogenesis.

We have previously demonstrated that UVB irradiation resulted in impaired function of cutaneous lymphatic vessels, suggesting a crucial role of lymphatic function in the mediation of UVB-induced inflammation. Nonetheless, the molecular mechanisms of lymphatic involvement in inflammation have remained unclear. Here, we show that vascular endothelial growth factor (VEGF)-C expression is downregulated after UVB irradiation, associated with enlargement of lymphatic vessels and with an increase of macrophage infiltration in the dermis. To determine whether activation of VEGF-C/VEGFR-3 signaling might reduce UVB-induced inflammation, mice were exposed to a single dose of UVB irradiation together with intradermal injection of mutant VEGF-C (Cys156Ser), which specifically binds to VEGFR-3 on lymphatic endothelium. We found that the activation of VEGFR-3 attenuated UVB-induced edema formation, associated with a decreased number of CD11b-positive macrophages. Moreover, mutant VEGF-C injection inhibited UVB-induced enlargement of lymphatic vessels and also induced the proliferation of lymphatic endothelial cells. In contrast, treatment with mutant VEGF-C had no effect on blood vessel size or number. These results demonstrate that UVB-induced lymphatic impairment is mediated by downregulation of VEGF-C expression and that the activation of the VEGF-C/VEGFR-3 pathway might represent a feasible target for the prevention of UVB-induced inflammation by promoting lymphangiogenesis.

Transcriptional profiling of VEGF-A and VEGF-C target genes in lymphatic endothelium reveals endothelial-specific molecule-1 as a novel mediator of lymphangiogenesis.

Lymphatic vessel growth and activation, mediated by vascular endothelial growth factor (VEGF)-C and/or VEGF-A, have important roles in metastasis and in chronic inflammation. We aimed to comprehensively identify downstream molecular targets induced by VEGF-A or VEGF-C in lymphatic endothelium by analyzing the time-series transcriptional profile of treated human dermal lymphatic endothelial cells (LECs). We identified a number of genes, many not previously known to be involved in lymphangiogenesis, that were characterized either as early response genes, transiently induced genes, or progressively induced genes. Endothelial-specific molecule-1 (ESM-1) was one of the genes that were most potently induced by both VEGF-A and VEGF-C. Whereas ESM-1 induction by VEGF-A was mainly dependent on activation of VEGFR-2, VEGF-C-mediated induction depended on the activity of both VEGFR-2 and VEGFR-3. Incubation of LECs with ESM-1 increased the stimulatory effects of both VEGF-A and VEGF-C on LEC proliferation and migration, whereas ESM-1 alone had no effect. Importantly, VEGF-A (or VEGF-C) induction of LEC proliferation and migration were significantly inhibited by siRNA-mediated silencing of ESM-1 in vitro and in vivo. These studies reveal ESM-1 as a novel mediator of lymphangiogenesis and as a potential target for the inhibition of pathologic lymphatic vessel activation.

Nitric oxide mediates lymphatic vessel activation via soluble guanylate cyclase alpha1beta1-impact on inflammation.

The lymphatic vascular system regulates tissue fluid homeostasis and the afferent phase of the immune response, and it is also involved in tumor metastasis. There is increasing evidence that lymphatic vessels also mediate acute and chronic inflammation. However, the mechanisms and functional consequences of lymphangiogenesis under inflammatory conditions are largely unknown. Here, we show that lymphatic endothelial cells (LECs) specifically express the alpha1beta1 isoform of soluble guanylate cyclase (sGC), that vascular endothelial growth factor-A potently induces sGCalpha1beta1, and that nitric oxide (NO) -induced LEC proliferation, migration, and cGMP production in LECs are specifically dependent on sGCalpha1beta1. Moreover, the specific sGC inhibitor NS-2028 completely prevents ultraviolet B-irradiation-induced lymphatic vessel enlargement, edema formation, and skin inflammation in vivo. These findings identify a crucial role of the NO/sGCalpha1beta1/cGMP pathway in modulating lymphatic vessel function. The blockade of sGCalpha1beta1 signaling might serve as a novel therapeutic strategy for inhibiting lymphangiogenesis and inflammation, in addition to its effects on the blood vasculature.