Enhanced expression of vascular endothelial growth factor in metastatic melanoma

STC1 competitively binding βPIX enhances melanoma progression via YAP nuclear translocation and M2 macrophage recruitment through the YAP/CCL2/VEGFA/AKT feedback loop

This study investigates the role of Stanniocalcin-1 (STC1) in melanoma progression, with a focus on its impact on metastasis, angiogenesis, and immune evasion. Systematic bioinformatics analysis revealed the potential influence of STC1 dysregulation on prognosis, immune cell infiltration, response to immune therapy, and cellular functions. In vitro assays were conducted to assess the proliferation, invasion, migration, and angiogenesis capabilities of A375 cells. In vivo experiments utilizing C57BL/6 J mice established a lung metastasis model using B16-F10 cells to evaluate macrophage infiltration and M2 polarization. A Transwell co-culture system was employed to explore the crosstalk between melanoma and macrophages. Molecular interactions among STC1, YAP, βPIX, and CCL2 are investigated using mass spectrometry, Co-Immunoprecipitation, Dual-Luciferase Reporter Assay, and Chromatin Immunoprecipitation experiments. STC1 was found to enhance lung metastasis by promoting the recruitment and polarization of M2 macrophages, thereby fostering an immunosuppressive microenvironment. Mechanistically, STC1 competes with YAP for binding to βPIX within the KER domain in melanoma cells, leading to YAP activation and subsequent CCL2 upregulation. CCL2-induced M2 macrophages secrete VEGFA, which enhances tumor vascularization and increases STC1 expression via the AKT signaling pathway in melanoma cells, establishing a pro-metastatic feedback loop. Notably, STC1-induced YAP activation increases PD-L1 expression, promoting immune evasion. Silencing STC1 enhances the efficacy of PD-1 immune checkpoint therapy in mice. This research elucidates STC1's role in melanoma metastasis and its complex interactions with tumor-associated macrophages, proposing STC1 as a potential therapeutic target for countering melanoma metastasis and augmenting the efficacy of PD-1 immunotherapy.

Angiogenesis Still Plays a Crucial Role in Human Melanoma Progression

Angiogenesis plays a pivotal role in tumor progression, particularly in melanoma, the deadliest form of skin cancer. This review synthesizes current knowledge on the intricate interplay between angiogenesis and tumor microenvironment (TME) in melanoma progression. Pro-angiogenic factors, including VEGF, PlGF, FGF-2, IL-8, Ang, TGF-β, PDGF, integrins, MMPs, and PAF, modulate angiogenesis and contribute to melanoma metastasis. Additionally, cells within the TME, such as cancer-associated fibroblasts, mast cells, and melanoma-associated macrophages, influence tumor angiogenesis and progression. Anti-angiogenic therapies, while showing promise, face challenges such as drug resistance and tumor-induced activation of alternative angiogenic pathways. Rational combinations of anti-angiogenic agents and immunotherapies are being explored to overcome resistance. Biomarker identification for treatment response remains crucial for personalized therapies. This review highlights the complexity of angiogenesis in melanoma and underscores the need for innovative therapeutic approaches tailored to the dynamic TME.

Recent advances in tyrosine kinase inhibitors VEGFR 1-3 for the treatment of advanced metastatic melanoma

INTRODUCTION

Increasing evidence from preclinical and clinical studies suggests the role of vascular endothelial growth factor (VEGF) signaling in melanoma progression, response to therapy, and overall survival. Moreover, the discovery of the potential involvement of the VEGF pathway in resistance to immunotherapy has led to new clinical trials with VEGFR inhibitors.

AREAS COVERED

We have reviewed recent literature, mainly published within the last 5 years, on VEGFR-targeted treatments for advanced melanoma, including mucosal, acral, and uveal melanoma. The VEGFR inhibitors were used as a single therapy or combined with either immunotherapy or chemotherapy, and they were employed in treatment for KIT-mutated cutaneous melanoma and for patients with brain metastases.

EXPERT OPINION

Trials involving monotherapy have been unsuccessful in demonstrating meaningful efficacy. Despite some activity, the combination of VEGFR-targeting tyrosine kinase inhibitors (TKIs) with immune checkpoint inhibitors (ICI) in patients with ICI-resistant melanoma, the combination did not significantly improve outcomes compared to anti-PD-1 monotherapy in the first-line settings. On the contrary, some patients with mucosal, acral or KIT-mutant melanoma may benefit from TKI-based therapies. Further studies focused on biomarker discovery and randomized trials are necessary to better understand the role of VEGFR1-3 as a therapeutic target in melanoma.

Deciphering ligand-receptor-mediated intercellular communication based on ensemble deep learning and the joint scoring strategy from single-cell transcriptomic data

BACKGROUND

Cell-cell communication in a tumor microenvironment is vital to tumorigenesis, tumor progression and therapy. Intercellular communication inference helps understand molecular mechanisms of tumor growth, progression and metastasis.

METHODS

Focusing on ligand-receptor co-expressions, in this study, we developed an ensemble deep learning framework, CellComNet, to decipher ligand-receptor-mediated cell-cell communication from single-cell transcriptomic data. First, credible LRIs are captured by integrating data arrangement, feature extraction, dimension reduction, and LRI classification based on an ensemble of heterogeneous Newton boosting machine and deep neural network. Next, known and identified LRIs are screened based on single-cell RNA sequencing (scRNA-seq) data in certain tissues. Finally, cell-cell communication is inferred by incorporating scRNA-seq data, the screened LRIs, a joint scoring strategy that combines expression thresholding and expression product of ligands and receptors.

RESULTS

The proposed CellComNet framework was compared with four competing protein-protein interaction prediction models (PIPR, XGBoost, DNNXGB, and OR-RCNN) and obtained the best AUCs and AUPRs on four LRI datasets, elucidating the optimal LRI classification ability. CellComNet was further applied to analyze intercellular communication in human melanoma and head and neck squamous cell carcinoma (HNSCC) tissues. The results demonstrate that cancer-associated fibroblasts highly communicate with melanoma cells and endothelial cells strong communicate with HNSCC cells.

CONCLUSIONS

The proposed CellComNet framework efficiently identified credible LRIs and significantly improved cell-cell communication inference performance. We anticipate that CellComNet can contribute to anticancer drug design and tumor-targeted therapy.

Circulating galectin-1 delineates response to bevacizumab in melanoma patients and reprograms endothelial cell biology

Blockade of vascular endothelial growth factor (VEGF) signaling with bevacizumab, a humanized anti-VEGF monoclonal antibody (mAb), or with receptor tyrosine kinase inhibitors, has improved progression-free survival and, in some indications, overall survival across several types of cancers by interrupting tumor angiogenesis. However, the clinical benefit conferred by these therapies is variable, and tumors from treated patients eventually reinitiate growth. Previously we demonstrated, in mouse tumor models, that galectin-1 (Gal1), an endogenous glycan-binding protein, preserves angiogenesis in anti-VEGF-resistant tumors by co-opting the VEGF receptor (VEGFR)2 signaling pathway in the absence of VEGF. However, the relevance of these findings in clinical settings is uncertain. Here, we explored, in a cohort of melanoma patients from AVAST-M, a multicenter, open-label, randomized controlled phase 3 trial of adjuvant bevacizumab versus standard surveillance, the role of circulating plasma Gal1 as part of a compensatory mechanism that orchestrates endothelial cell programs in bevacizumab-treated melanoma patients. We found that increasing Gal1 levels over time in patients in the bevacizumab arm, but not in the observation arm, significantly increased their risks of recurrence and death. Remarkably, plasma Gal1 was functionally active as it was able to reprogram endothelial cell biology, promoting migration, tubulogenesis, and VEGFR2 phosphorylation. These effects were prevented by blockade of Gal1 using a newly developed fully human anti-Gal1 neutralizing mAb. Thus, using samples from a large-scale clinical trial from stage II and III melanoma patients, we validated the clinical relevance of Gal1 as a potential mechanism of resistance to bevacizumab treatment.

Involvement of platelet-derived VWF in metastatic growth of melanoma in the brain

Background

The prognosis of patients with brain metastases (BM) is poor despite advances in our understanding of the underlying pathophysiology. The high incidence of thrombotic complications defines tumor progression and the high mortality rate. We, therefore, postulated that von Willebrand factor (VWF) promotes BM via its ability to induce platelet aggregation and thrombosis.

Methods

We measured the abundance of VWF in the blood and intravascular platelet aggregates of patients with BM, and determined the specific contribution of endothelial and platelet-derived VWF using in vitro models and microfluidics. The relevance for the brain metastatic cascade in vivo was demonstrated in ret transgenic mice, which spontaneously develop BM, and by the intracardiac injection of melanoma cells.

Results

Higher levels of plasma VWF in patients with BM were associated with enhanced intraluminal VWF fiber formation and platelet aggregation in the metastatic tissue and peritumoral regions. Platelet activation triggered the formation of VWF multimers, promoting platelet aggregation and activation, in turn enhancing tumor invasiveness. The absence of VWF in platelets, or the blocking of platelet activation, abolished platelet aggregation, and reduced tumor cell transmigration. Anticoagulation and platelet inhibition consistently reduced the number of BM in preclinical animal models.

Conclusions

Our data indicate that platelet-derived VWF is involved in cerebral clot formation and in metastatic growth of melanoma in the brain. Targeting platelet activation with low-molecular-weight heparins represents a promising therapeutic approach to prevent melanoma BM.

Aberrant Expression of Immunohistochemical Markers in Malignant Melanoma: A Review

Immunohistochemical stains are increasingly used to aid in the diagnosis of malignant melanoma, especially when the differentiation of the tumor is unclear based on examination with hematoxylin and eosin. However, aberrant expression of non-melanocytic markers has been reported in melanomas, which can sometimes be further complicated by the loss of conventional melanocytic markers. This review aims to summarize available data regarding unusual staining patterns in primary and metastatic malignant melanoma. It also raises awareness of the potential pitfalls and highlights the importance of appropriate use and interpretation of broad immunohistochemical markers in the context of clinical and histopathologic findings to facilitate the diagnosis of atypical cases of malignant melanoma.

A Microfluidic 3D Endothelium-on-a-Chip Model to Study Transendothelial Migration of T Cells in Health and Disease

The recruitment of T cells is a crucial component in the inflammatory cascade of the body. The process involves the transport of T cells through the vascular system and their stable arrest to vessel walls at the site of inflammation, followed by extravasation and subsequent infiltration into tissue. Here, we describe an assay to study 3D T cell dynamics under flow in real time using a high-throughput, artificial membrane-free microfluidic platform that allows unimpeded extravasation of T cells. We show that primary human T cells adhere to endothelial vessel walls upon perfusion of microvessels and can be stimulated to undergo transendothelial migration (TEM) by TNFα-mediated vascular inflammation and the presence of CXCL12 gradients or ECM-embedded melanoma cells. Notably, migratory behavior was found to differ depending on T cell activation states. The assay is unique in its comprehensiveness for modelling T cell trafficking, arrest, extravasation and migration, all in one system, combined with its throughput, quality of imaging and ease of use. We envision routine use of this assay to study immunological processes and expect it to spur research in the fields of immunological disorders, immuno-oncology and the development of novel immunotherapeutics.

Heterogeneous Expression of Proangiogenic and Coagulation Proteins in Gliomas of Different Histopathological Grade

Brain gliomas are characterized by remarkably intense invasive growth and the ability to create new blood vessels. Angiogenesis is a key process in the progression of these tumors. Coagulation and fibrinolysis factors play a role in promoting angiogenesis. The aim of the study was to evaluate the expression of proangiogenic proteins (VEGF and bFGF) and hemostatic proteins (TF, fibrinogen, fibrin, D-dimers) associated with neoplastic cells and vascular endothelial cells in brain gliomas of various degrees of malignancy. Immunohistochemical tests were performed using the ABC method with the use of mono- and polyclonal antibodies. The obtained results indicated that both neoplastic cells and vascular endothelial cells in gliomas of various degrees of malignancy are characterized by heterogeneous expression of proteins of the hemostatic system and angiogenesis markers. The strongest expression of proangiogenic factors and procoagulant factors was demonstrated in gliomas of higher-grade malignancy.

Chemotherapy combined with antiangiogenic drugs as salvage therapy in advanced melanoma patients progressing on PD-1 immunotherapy

BACKGROUND

This study aimed to evaluate the effect of salvage therapy with nab-paclitaxel (nab-p) or temozolomide (TMZ) combined with antiangiogenic drugs in programmed death 1 (PD-1) inhibitor-resistant patients with unresectable metastatic melanoma.

METHODS

We conducted a retrospective review of 69 metastatic melanoma patients who received nab-p or TMZ combined with antiangiogenic drugs after developing PD-1 inhibitor resistance and were treated at the Beijing Cancer Hospital between 2016 and 2019. The disease control rate (c-DCR) and progression-free survival (c-PFS) of salvage CA (chemotherapy combined with antiangiogenic drugs) regimens were investigated. Univariate and multivariate analyses were performed to evaluate the clinical pathological factors affecting the outcomes. Then, a nomogram was formulated to predict the probability of 3-month and 6-month c-PFS based on the multivariate analysis results.

RESULTS

The c-DCR was 63.8%, and the median c-PFS was 3.0 months. In the univariate analysis, factors associated with the c-DCR were included the melanoma subtype, baseline platelet-to-lymphocyte ratio (PLR) and best response status to PD-1 inhibitors. Factors influencing c-PFS included age, baseline lactic dehydrogenase, PLR, neutrophil-to-lymphocyte ratio (NLR), PFS duration of anti-PD-1 therapy (p-PFS), and the best response and progression pattern of PD-1 inhibitors. In the multivariate analysis, age <65 years, heterogeneous progression pattern and baseline PLR<200 were significantly associated with improved c-PFS. The concordance index (C-index) of the nomogram was equal to 0.65 (95% CI 0.566-0.734).

CONCLUSIONS

CA regimens demonstrated promising effects in PD-1 inhibitor-resistant patients. The nomogram could be a valuable predictive module for salvage therapy choice in PD-1 inhibitor-resistant patients.

Adjuvant bevacizumab for melanoma patients at high risk of recurrence: survival analysis of the AVAST-M trial

Background

Bevacizumab is a recombinant humanised monoclonal antibody to vascular endothelial growth factor shown to improve survival in advanced solid cancers. We evaluated the role of adjuvant bevacizumab in melanoma patients at high risk of recurrence.

Patients and methods

Patients with resected AJCC stage IIB, IIC and III cutaneous melanoma were randomised to receive either adjuvant bevacizumab (7.5 mg/kg i.v. 3 weekly for 1 year) or standard observation. The primary end point was detection of an 8% difference in 5-year overall survival (OS) rate; secondary end points included disease-free interval (DFI) and distant metastasis-free interval (DMFI). Tumour and blood were analysed for prognostic and predictive markers.

Results

Patients (n=1343) recruited between 2007 and 2012 were predominantly stage III (73%), with median age 56 years (range 18–88 years). With 6.4-year median follow-up, 515 (38%) patients had died [254 (38%) bevacizumab; 261 (39%) observation]; 707 (53%) patients had disease recurrence [336 (50%) bevacizumab, 371 (55%) observation]. OS at 5 years was 64% for both groups [hazard ratio (HR) 0.98; 95% confidence interval (CI) 0.82–1.16, P = 0.78). At 5 years, 51% were disease free on bevacizumab versus 45% on observation (HR 0.85; 95% CI 0.74–0.99, P = 0.03), 58% were distant metastasis free on bevacizumab versus 54% on observation (HR 0.91; 95% CI 0.78–1.07, P = 0.25). Forty four percent of 682 melanomas assessed had a BRAF^V600 mutation. In the observation arm, BRAF mutant patients had a trend towards poorer OS compared with BRAF wild-type patients (P = 0.06). BRAF mutation positivity trended towards better OS with bevacizumab (P = 0.21).

Conclusions

Adjuvant bevacizumab after resection of high-risk melanoma improves DFI, but not OS. BRAF mutation status may predict for poorer OS untreated and potential benefit from bevacizumab.

Clinical Trial Information

ISRCTN 81261306; EudraCT Number: 2006-005505-64

Expression of VEGF in human conjunctival melanoma analyzed with immunohistochemistry

Purpose

The aim of this study was to examine the immunolocalization of VEGF-A and CD34, a marker of endothelial cells, in human conjunctival melanoma.

Methods

This study retrospectively analyzed primary conjunctival melanoma patients who underwent surgical resection of the tumor. All excised tissues were fixed with paraformaldehyde and embedded in paraffin, which were then submitted for immunohistochemistry with anti-VEGF and CD34 antibodies.

Results

The study sample comprised 4 female and two male melanoma patients. The age of the patients ranged from 64 to 84 (average age, 73) years. Histopathology of the surgically resected tumor tissues demonstrated accumulation of polygonal atypical malignant cells producing melanin. Cytoplasmic immunoreactivity for VEGF was clearly observed in tumor cells of all six tumors. In contrast, CD34-positive endothelial cells were less marked in the melanoma tissues than in the adjacent noncancerous subconjunctival stroma.

Conclusion

VEGF immunoreactivity was observed in conjunctival melanoma tissues, in which endothelial cells were hardly observed. These results suggest that although VEGF is expressed, conjunctival melanoma is a hypovascular tumor.

NCI 8628: A randomized phase 2 study of ziv-aflibercept and high-dose interleukin 2 or high-dose interleukin 2 alone for inoperable stage III or IV melanoma

BACKGROUND

Interleukin 2 (IL-2) is a growth factor for T and natural killer cells, promotes proinflammatory cytokines, and can lead to durable responses in patients with melanoma. Vascular endothelial growth factor (VEGF) promotes angiogenesis and modulates host innate and adaptive immunity. High VEGF levels were found to be associated with nonresponse to IL-2. Ziv-aflibercept may deplete VEGF and thereby enhance antitumor T-cell responses, thus supporting a combination immunotherapeutic strategy with IL-2.

METHODS

NCI 8628 was a phase 2 trial of ziv-aflibercept and IL-2 (arm A) versus IL-2 alone (arm B) randomized at 2:1, respectively. Eligible patients had inoperable American Joint Committee on Cancer stage III or stage IV melanoma. The primary endpoint was progression-free survival (PFS).

RESULTS

A total of 89 patients were enrolled and 84 patients were treated. The median follow-up was 41.4 months. Among treated patients (55 patients in arm A and 29 patients in arm B), PFS was significantly improved in favor of arm A, with a median of 6.9 months (95% confidence interval [95% CI], 4.1-8.7 months) versus 2.3 months (95% CI, 1.6-3.5 months) (P<.001). No significant difference was noted with regard to overall survival, with a median of 26.9 months (95% CI, 14.4-63.6 months) for arm A and 24.2 months (95% CI, 11.3-36.4 months) for arm B. The response rate (according to Response Evaluation Criteria In Solid Tumors [RECIST]) was 22% in arm A (4 complete responses [CRs] and 8 partial responses [PRs]) and 17% in arm B (1 CR and 4 PRs). Stable disease or PR or CR was noted in 65% of patients in arm A and 48% of patients in arm B. The combination was found to be superior to monotherapy in patients with high and low levels of serum VEGF and VEGF receptor 2. Adverse events were consistent with the expected profiles of monotherapy with IL-2 and ziv-aflibercept.

CONCLUSIONS

Ziv-aflibercept and IL-2 were found to significantly improve PFS compared with IL-2 alone, thereby meeting the primary endpoint of the current study. These findings support further study of immunotherapeutic combination strategies involving VEGF inhibitors.

RAGE-aptamer Attenuates the Growth and Liver Metastasis of Malignant Melanoma in Nude Mice

Epidemiological studies have suggested the link between cumulative diabetic exposure and cancer. Interaction of advanced glycation end products (AGEs) with their receptor (RAGE) may contribute to the phenomenon. We examined here the effects of DNA aptamer raised against RAGE (RAGE-aptamer) on growth and liver metastasis of G361 melanoma in nude mice. Malignant melanoma cells were intradermally injected into the upper flank region of nude mice, which received continuous administration of RAGE-aptamer (38.4 pmol/day/g body weight) or vehicle intraperitoneally by an osmotic pump up to 42 days. RAGE-aptamer significantly reduced levels of 8-hydroxy-2'-deoxy-guanosine, AGEs, RAGE, proliferating nuclear antigen, cyclin D1, vascular endothelial growth factor (VEGF), monocyte chemoattractant protein-1 (MCP-1), and CD31 and Mac-3, respective markers of endothelial cells and macrophages in tumors of nude mice and suppressed the proliferation and liver metastasis of malignant melanoma. Furthermore, RAGE-aptamer attenuated the AGE-induced oxidative stress generation, proliferation, and VEGF and MCP-1 gene expression in both G361 melanoma cells and endothelial cells. The present findings suggest that RAGE-aptamer could attenuate melanoma growth and liver metastasis in nude mice by suppressing the tumor angiogenesis and macrophage infiltration via inhibition of the AGE-RAGE system. RAGE-aptamer may be a novel therapeutic tool for the treatment of malignant melanoma.

Angiogenesis in Dermatology - Insights of Molecular Mechanisms and Latest Developments

Angiogenesis is the growth of new blood vessels from pre-existing vessels. It is a biological process essential in physiological wound healing or pathological inflammation and tumor growth, which underlies a complex interplay of stimulating and inhibiting signals. Extracellular matrix, cells of innate and adaptive immunity and endothelial cells itself are a major source of angiogenic factors that activate or inhibit specific receptors and consequently influence intracellular signaling pathways. Most inflammatory and neoplastic diseases in dermatology are characterized by excessive angiogenesis, such as psoriasis, atopic dermatitis, as well as melanoma, non-melanoma skin cancer, but also benign vascular neoplasia. In this article we describe current knowledge of angiogenesis and its most relevant mechanisms in different dermatological disorders with particular emphasis on the angiogenic factors (vascular endothelial growth factor) and angiopoietins as a target of current and future directions of anti-angiogenic therapy.

Predicting lymph node metastasis in patients with papillary thyroid carcinoma by vascular index on power Doppler ultrasound

BACKGROUND

For patients with papillary thyroid carcinoma (PTC), lymph node metastasis is associated with an increased recurrence rate. The purpose of this study was to investigate whether the vascular endothelial growth factor (VEGF), microvessel density (MVD), and vascular index (VI) can predict lymph node metastasis in patients with PTC.

METHODS

From January 2011 to October 2011, 202 patients with PTCs underwent preoperative staging ultrasound evaluation. To evaluate vascularity, we measured the VI, VEGF expression, and MVD.

RESULTS

The VI was significantly correlated with MVD (p = .009). On multivariate analysis, young age showed a significant correlation with lymph node metastasis (p < .001; p < .001; p < .001). However, the other clinicopathologic features, VEGF, MVD, and VI failed to show any significant correlations with lymph node metastasis.

CONCLUSION

Although the VI showed significant correlation with MVD, it was not significantly correlated to lymph node metastasis. © 2016 Wiley Periodicals, Inc. Head Neck 39: 334-340, 2017.

The role of miRNAs in cutaneous squamous cell carcinoma

MicroRNAs (miRs) are small, noncoding RNAs that negatively regulate gene expressions at posttranscriptional level. Each miR can control hundreds of gene targets and play important roles in various biological and pathological processes such as hematopoiesis, organogenesis, cell apoptosis and proliferation. Aberrant miR expression contributes to initiation and cell progression of cancers. Accumulating studies have found that miRs play a significant role in cutaneous squamous cell carcinoma (cSCC). Deregulations of miRs may contribute to cSCC carcinogenesis is through acting as oncogenic or tumour suppressive miRs. In this study, we summarized the recent data available on cSCC‐associated miRs. In particular, we will discuss the contribution of miR to the initiation and progression of cSCCs. Although there are many obstacles to be overcome, clinical use of miRs as biomarkers for diagnosis, prediction of prognosis and target for therapies, will be a promising area in the future with more expression and functional role of miRs revealed.

The combination of axitinib followed by paclitaxel/carboplatin yields extended survival in advanced BRAF wild-type melanoma: results of a clinical/correlative prospective phase II clinical trial

BACKGROUND

Simultaneous chemotherapy with vascular endothelial growth factor (VEGF) inhibition has not shown additional benefit over chemotherapy alone in advanced melanoma. We tested administration of the potent VEGF inhibitor axitinib followed by paclitaxel/carboplatin to determine whether enhanced tumour proliferation during axitinib withdrawal leads to sustained chemosensitivity.

METHODS

We conducted a prospective phase II trial in metastatic melanoma patients with ECOG performance status 0-1 and normal organ function. Axitinib 5 mg PO b.i.d. was taken on days 1-14 of each 21-day treatment cycle, and carboplatin (AUC=5) with paclitaxel (175 mg m(-2)) was administered on day 1 starting with cycle 2. 3'-Deoxy-3'-(18)F-fluorothymidine ((18)F-FLT)-PET scans were performed in five patients to assess tumour proliferation on days 1, 14, 17, and 20 of cycle 1. Molecular profiling for BRAF was performed for all patients with cutaneous, acral, or mucosal melanoma.

RESULTS

The treatment was well tolerated. The most common grade 3 AEs were hypertension, neutropenia, and anaemia. Grade 4 non-haematologic AEs were not observed. Four of five patients completing (18)F-FLT-PET scans showed increases (23-92%) in SUV values during the axitinib holiday. Of 36 evaluable patients, there were 8 confirmed PRs by Response Evaluation Criteria in Solid Tumors. Overall, 20 patients had SD and 8 had PD as the best response. The median PFS was 8.7 months and the median overall survival was 14.0 months. Five BRAF(V600E/K) patients had significantly worse PFS than patients without these mutations.

CONCLUSIONS

Axitinib followed by carboplatin and paclitaxel was well tolerated and effective in BRAF wild-type metastatic melanoma. 3'-Deoxy-3'-(18)F-fluorothymidine-PET scans showed increased proliferation during axitinib withdrawal.

Phase II study of nab-paclitaxel and bevacizumab as first-line therapy for patients with unresectable stage III and IV melanoma

OBJECTIVES

This study was an open-label multicenter phase II trial to investigate the efficacy and safety of nab-paclitaxel and bevacizumab as first-line therapy in patients with histologically confirmed unresectable metastatic melanoma.

METHODS

The treatment regimen consisted of a 28-day cycle in which patients received nab-paclitaxel, 150 mg/m through intravenous (IV) infusion weekly for 3 weeks and bevacizumab, 10 mg/kg IV every 2 weeks without a rest period. The 28-day cycle was repeated until there was unacceptable toxicity or disease progression. If 1 drug had to be stopped because of toxicity, treatment was continued with the other drug until disease progression or unacceptable toxicity. The primary endpoint was the progression-free survival rate (PFS) at 4 months.

RESULTS

Fifty patients were enrolled. The PFS rate at 4 months was 75%. The median PFS was 7.6 months and the median overall survival was 16.8 months with a median duration follow-up of 41.6 months. The overall survival rate was 64% at 1 year and 30% at 2 years. Ten patients (20%) remain alive. The objective response rate was 36%. Common adverse events associated with this regimen were peripheral neuropathy, fatigue, alopecia, and gastrointestinal disorders.

CONCLUSIONS

In this phase II multicenter study, this doublet had significant activity in patients with metastatic melanoma, and was well tolerated. These results are promising and follow-up trials to further explore this regimen are warranted.

Circulating biomarkers in malignant melanoma

Melanoma is an aggressive tumor with increasing incidence worldwide. Biomarkers are valuable tools to minimize the cost and improve efficacy of treatment of this deadly disease. Serological markers have not widely been introduced in routine clinical practice due to their insufficient diagnostic sensitivity and specificity. It is likely that the lack of objective responses with traditional treatment hinder biomarker research and development in melanoma. Recently, new drugs and therapies have, however, emerged in advanced melanoma with noticeable objective response ratio and survival. In this new scenario, serological tumor markers should be revisited. In addition, other potential circulating biomarkers such as cell-free DNA, exosomes, microRNA, and circulating tumor cells have also been identified. In this review, we summarize classical and emerging tumor markers and discuss their possible roles in emerging therapeutics.

Microvessel density, lymphovascular density, and lymphovascular invasion in primary cutaneous melanoma-correlation with histopathologic prognosticators and BRAF status

The relationship between microvessel density (MVD), lymphovascular density (LVD), and lymphovascular invasion (LVI) in primary cutaneous melanoma (PCM) remains unclear. Given this, a total of 102 PCMs were assessed for MVD (vascular endothelial growth factor receptor 2 and Endocan), LVD (D2-40), and LVI (immunostaining with D2-40/S-100 and hematoxylin and eosin); tumoral S-100A13, vascular endothelial growth factor receptor 2, and Endocan; and BRAF status. LVD was associated with MVD (P = .01). MVD was higher in PCMs with depth greater than or equal to 2 mm and ulceration (P = .04, .05), whereas LVD was higher in PCMs with depth greater than or equal to 2 mm and mitoses (P = .03, .02). After adjusting for MVD and LVD, only ulceration was associated with LVI (P < .02). A BRAF mutation was seen in 30.4% cases, and when present, both LVD and host response (P = .0008 and .04, respectively) were significantly associated with MVD. Immunostaining with S-100A13 was noted in 99% of cases and a significant association noted only with ulceration (P = .05). Immunostaining increased LVI positivity (46.5% versus 4.9% by hematoxylin and eosin, P < .0001). MVD and LVD are not associated with LVI, appear to be closely related with each other, and are associated with select markers of poor prognosticative value. The association between a host response and LVD and MVD in PCMs with a BRAF mutation suggests that they exhibit potential for strategizing immunotherapies.

Lymphangiogenesis and its correlation with the VEGF expression and the sentinel lymph node in cutaneous melanomas

The aim of the study is to evaluate the density of intratumoral and peritumoral lymphatic vessels in primary cutaneous melanomas and to assess their correlation with the status of sentinel lymph nodes and the VEGF expression in tumor cells and stromal cells. A total of 40 patients were enrolled in the study: the melanomas were radically excised with the extirpation of the sentinel lymph node. The study subjects were divided into two groups: 20 cases with positive and 20 cases with negative sentinel lymph node results. The density of lymphatic vessels was evaluated by the antibody D2-40 and the VEGF expression was investigated in the semiquantitative way. The VEGF expression in melanoma cells and the stromal cells was negative to variable positive at both SLN negative and SLN positive patients in all pT stages. In the group of SLN positive patients, the density of intratumoral lymphatic vessels was low up to moderate, while it was observed to be absent, somewhere on the low level in the group of SLN negative patients. On the other side, the density of peritumoral lymphatic vessels was equally numerous at both SLN negative and SLN positive patients. The lymphatic invasion was found out at 4 SLN positive patients only. The ulceration was chiefly in the group of LN positive patients. The results show that the density of lymphangiogenesis and the intensity of the VEGF expression are considered to be an unreliable predictor of melanoma metastasis to the sentinel lymph node, but the ulceration and the lymphatic invasion can predict the potential for metastasis.

Adjuvant bevacizumab in patients with melanoma at high risk of recurrence (AVAST-M): preplanned interim results from a multicentre, open-label, randomised controlled phase 3 study

BACKGROUND

Bevacizumab, a monoclonal antibody that targets VEGF, has shown restricted activity in patients with advanced melanoma. We aimed to assess the role of bevacizumab as adjuvant treatment for patients with resected melanoma at high risk of recurrence. We report results from the preplanned interim analysis.

METHODS

We did a multicentre, open-label, randomised controlled phase 3 trial at 48 centres in the UK between July 18, 2007, and March 29, 2012. Patients aged 16 years or older with American Joint Committee on Cancer stage (AJCC) stage IIB, IIC, and III cutaneous melanoma were randomly allocated (1:1), via a central, computer-based minimisation procedure, to receive intravenous bevacizumab 7.5 mg/kg, every 3 weeks for 1 year, or to observation. Randomisation was stratified by Breslow thickness of the primary tumour, N stage according to AJCC staging criteria, ulceration of the primary tumour, and patient sex. The primary endpoint was overall survival; secondary endpoints included disease-free interval, distant-metastases interval and quality of life. Analysis was by intention-to-treat. This trial is registered as an International Standardised Randomised Controlled Trial, number ISRCTN81261306.

FINDINGS

1343 patients were randomised to either the bevacizumab group (n=671) or the observation group (n=672). Median follow-up was 25 months (IQR 16-37) in the bevacizumab group and 25 months (17-37) in the observation group. At the time of interim analysis, 286 (21%) of 1343 enrolled patients had died: 140 (21%) of 671 patients in the bevacizumab group, and 146 (22%) of 672 patients in the observation group. 134 (96%) of patients in the bevacizumab group died because of melanoma versus 139 (95%) in the observation group. We noted no significant difference in overall survival between treatment groups (hazard ratio [HR] 0.97, 95% CI 0.78-1.22; p=0.76); this finding persisted after adjustment for stratification variables (HR 1.03; 95% CI 0.81-1.29; p=0.83). Median duration of treatment with bevacizumab was 51 weeks (IQR 21-52) and dose intensity was 86% (41-96), showing good tolerability. 180 grade 3 or 4 adverse events were recorded in 101 (15%) of 671 patients in the bevacizumab group, and 36 (5%) of 672 patients in the observation group. Bevacizumab resulted in a higher incidence of grade 3 hypertension than did observation (41 [6%] vs one [<1%]). There was an improvement in disease-free interval for patients in the bevacizumab group compared with those in the observation group (HR 0.83, 95% CI 0.70-0.98, p=0.03), but no significant difference between groups for distant-metastasis-free interval (HR 0.88, 95% CI 0.73-1.06, p=0.18). No significant differences were noted between treatment groups in the standardised area under the curve for any of the quality-of-life scales over 36 months. Three adverse drug reactions were regarded as both serious and unexpected: one patient had optic neuritis after the first bevacizumab infusion, a second patient had persistent erectile dysfunction, and a third patient died of a haemopericardium after receiving two bevacizumab infusions and was later identified to have had significant predisposing cardiovascular risk factors.

INTERPRETATION

Bevacizumab has promising tolerability. Longer follow-up is needed to identify an effect on the primary endpoint of overall survival at 5 years.

DNA aptamer raised against advanced glycation end products inhibits melanoma growth in nude mice

Epidemiological studies have suggested that diabetes is associated with an increased risk of cancer. However, the underlying molecular mechanism remains unclear. We investigated here whether DNA aptamer directed against advanced glycation end products (AGE-aptamer) inhibited melanoma growth in nude mice. G361 melanoma cells were injected intradermally into the upper flank of athymic nude mice. Mice received continuous intraperitoneal infusion (0.136 μg/day) of either AGE-aptamer (n=9) or Control-aptamer (n=8) by an osmotic mini pump. Tumor volume was measured at 4-day interval, and G361 melanoma was excised at day 43 after the aptamer treatment. We further examined the effects of AGE-aptamer on proliferation of AGE-exposed endothelial cells and G361 cells. AGE-aptamer significantly inhibited the in vivo-tumor growth of G361 melanoma. Immunohistochemical and western blotting analyses of G361 melanoma revealed that AGE-aptamer decreased expression levels of proliferating nuclear antigen, CD31 and Mac-3, markers of endothelial cells and macrophages, respectively. AGE-aptamer significantly decreased the number of tumor-associated vessels. AGE, receptor for AGE (RAGE) and vascular endothelial growth factor levels were also reduced in AGE-aptamer-treated G361 melanoma. AGE-aptamer inhibited the AGE-induced proliferation and tube formation of endothelial cells as well as the growth of G361 cells in vitro. The present findings suggest that AGE-aptamer could inhibit the AGE-RAGE axis in G361 melanoma and resultantly suppress the tumor growth in nude mice by blocking the angiogenesis. AGE-aptamer might be a novel therapeutic strategy for preventing the progression of malignant melanoma in diabetes.

Why is melanoma so metastatic?

Malignant melanoma is one of the most aggressive cancers and can disseminate from a relatively small primary tumor and metastasize to multiple sites, including the lung, liver, brain, bone, and lymph nodes. Elucidating the molecular and genetic changes that take place during the metastatic process has led to a better understanding of why melanoma is so metastatic. Herein, we describe the unique features that distinguish melanoma from other solid tumors and contribute to the malignant phenotype of melanoma cells. For example, although melanoma cells are highly antigenic, they are extremely efficient at evading host immune response. Melanoma cells share numerous cell surface molecules with vascular cells, are highly angiogenic, are mesenchymal in nature, and possess a higher degree of 'stemness' than do other solid tumors. Finally, analysis of melanoma mutations has revealed that the gene expression profile of malignant melanoma is different from that of other cancers. Elucidating these molecular and genetic processes in highly metastatic melanoma can lead to the development of improved treatment and individualized therapy options.

ECOG phase II trial of graded-dose peginterferon α-2b in patients with metastatic melanoma overexpressing basic fibroblast growth factor (E2602)

PURPOSE

We investigated the use of graded-dose peginterferon α-2b (Peg-IFN) in patients with stage IV melanoma overexpressing basic fibroblast growth factor (FGF-2). The primary objective was suppression of plasma FGF-2 to within reference range (≤ 7.5 pg/mL).

EXPERIMENTAL DESIGN

Plasma FGF-2 was measured at baseline (step 1), and patients with concentrations of 15 pg/mL or more were eligible for study treatment (step 2). Peg-IFN was given weekly at a starting dose of 0.5 μg/kg/wk with increment every 3 weeks based on serial FGF-2 concentrations.

RESULTS

Two hundred seven patients entered step 1; 45 (22%) overexpressed FGF-2 (median = 22 pg/dL). Twenty-nine eligible patients entered step 2 and received treatment. Patients' median age was 64 years (range, 29-84 years). Most had more than two prior therapies. FGF-2 decreased in 28 (97%) patients, with suppression to reference range in 10 (35%). Median time to FGF-2 suppression was 30 days. The best clinical responses were partial response (7%) and stable disease (17%). Median progression-free survival (PFS) and overall survival (OS) were 2.0 and 9.7 months, respectively. Patients who achieved FGF-2 suppression were more likely than those who did not to have a response or stable disease (P = 0.03). VEGF concentrations decreased in 27 patients (93%) during treatment and paralleled those of FGF-2 over time. We found no compensatory increase in VEGF among those with FGF-2 suppression.

CONCLUSIONS

Graded-dose Peg-IFN suppresses FGF-2 in patients with metastatic melanoma who overexpress FGF-2. Over one third of patients had complete suppression of plasma FGF-2, which correlated with clinical response to this therapy.

The effect of bevacizumab on human malignant melanoma cells with functional VEGF/VEGFR2 autocrine and intracrine signaling loops

Receptors for the angiogenic factor VEGF are expressed by tumor cancer cells including melanoma, although their functionality remains unclear. Paired human melanoma cell lines WM115 and WM239 were used to investigate differences in expression and functionality of VEGF and VEGFR2 in vitro and in vivo with the anti-VEGF antibody bevacizumab. Both WM115 and WM239 cells expressed VEGF and VEGFR2, the levels of which were modulated by hypoxia. Detection of native and phosphorylated VEGFR2 in subcellular fractions under serum-free conditions showed the presence of a functional autocrine as well as intracrine VEGF/VEGFR2 signaling loops. Interestingly, treatment of WM115 and WM239 cells with increasing doses of bevacizumab (0-300 µg/ml) in vitro did not show any significant inhibition of VEGFR2 phosphorylation. Small-molecule tyrosine kinase inhibitor, sunitinib, caused an inhibition of VEGFR2 phosphorylation in WM239 but not in WM115 cells. An increase in cell proliferation was observed in WM115 cells treated with bevacizumab, whereas sunitinib inhibited proliferation. When xenografted to immune-deficient mice, we found bevacizumab to be an effective antiangiogenic but not antitumorigenic agent for both cell lines. Because bevacizumab is unable to neutralize murine VEGF, this supports a paracrine angiogenic response. We propose that the failure of bevacizumab to generate an antitumorigenic effect may be related to its generation of enhanced autocrine/intracrine signaling in the cancer cells themselves. Collectively, these results suggest that, for cancers with intracrine VEGF/ VEGFR2 signaling loops, small-molecule inhibitors of VEGFR2 may be more effective than neutralizing antibodies at disease control.

A randomized phase 2 study of temozolomide and bevacizumab or nab-paclitaxel, carboplatin, and bevacizumab in patients with unresectable stage IV melanoma : a North Central Cancer Treatment Group study, N0775

BACKGROUND

Increasing evidence shows chemotherapy in combination with vascular endothelial growth factor (VEGF) inhibition is a clinically active therapy for patients with metastatic melanoma (MM).

METHODS

A phase 2 trial was conducted in chemotherapy-naive patients with unresectable stage IV MM who were randomized to temozolomide (200 mg/m(2) on days 1 through 5) and bevacizumab (10 mg/kg intravenously on days 1 and 15) every 28 days (Regimen TB) or nab-paclitaxel (100 mg/m(2) , or 80 mg/m(2) post-addendum 5 secondary to toxicity, on days 1, 8, and 15), bevacizumab (10 mg/kg on days 1 and 15), and carboplatin (area under the curve [AUC] 6 on day 1, or AUC 5 post-addendum 5) every 28 days (Regimen ABC). Accrual goal was 41 patients per regimen. The primary aim of this study was to estimate progression-free survival rate at 6 months (PFS6) in each regimen. A regimen would be considered promising if its PFS6 rate was > 60%.

RESULTS

Ninety-three eligible patients (42 TB and 51 ABC) were enrolled. The majority of patients had M1c disease (20 TB and 26 ABC). The median PFS and overall survival times with ABC were 6.7 months and 13.9 months, respectively. Median PFS time and median overall survival with TB were 3.8 months and 12.3 months, respectively. The most common severe toxicities (≥ grade 3) in both regimens were cytopenias, fatigue, and thrombosis. Among the first 41 patients enrolled onto each regimen, PFS6 rate was 32.8% (95% confidence interval: 21.1%-51.2%) for TB and 56.1% (90% confidence interval: 44.7%-70.4%) for ABC.

CONCLUSIONS

The addition of bevacizumab to nab-paclitaxel and carboplatin shows promising activity despite tolerability issues.

The expression levels of microRNA-361-5p and its target VEGFA are inversely correlated in human cutaneous squamous cell carcinoma

Vascular endothelial growth factor A (VEGFA) plays a key role in the angiogenesis of human skin. Elevated levels of VEGFA are associated with several pathological conditions, including chronic inflammatory skin diseases and several types of skin cancer. In particular, squamous cell carcinoma (SCC) of the skin, the second most common skin cancer in the general population, is characterized by invasive growth, pronounced angiogenesis and elevated levels of VEGFA. The processing, turnover and production of VEGFA are extensively regulated at the post-transcriptional level, both by RNA-binding proteins and microRNAs (miRNAs). In the present study, we identified a new miRNA recognition element in a downstream conserved region of the VEGFA 3'-UTR. We confirmed the repressive effect of miR-361-5p on this element in vitro, identifying the first target for this miRNA. Importantly, we found that miR-361-5p levels are inversely correlated with VEGFA expression in SCC and in healthy skin, indicating that miR-361-5p could play a role in cancers.

Stabilization of HIF-2α induces sVEGFR-1 production from tumor-associated macrophages and decreases tumor growth in a murine melanoma model

Macrophage secretion of vascular endothelial growth factor (VEGF) in response to hypoxia contributes to tumor growth and angiogenesis. In addition to VEGF, hypoxic macrophages stimulated with GM-CSF secrete high levels of a soluble form of the VEGF receptor (sVEGFR-1), which neutralizes VEGF and inhibits its biological activity. Using mice with a monocyte/macrophage-selective deletion of hypoxia-inducible factor (HIF)-1α or HIF-2α, we recently demonstrated that the antitumor response to GM-CSF was dependent on HIF-2α-driven sVEGFR-1 production by tumor-associated macrophages, whereas HIF-1α specifically regulated VEGF production. We therefore hypothesized that chemical stabilization of HIF-2α using an inhibitor of prolyl hydroxylase domain 3 (an upstream inhibitor of HIF-2α activation) would increase sVEGFR-1 production from GM-CSF-stimulated macrophages. Treatment of macrophages with the prolyl hydroxylase domain 3 inhibitor AKB-6899 stabilized HIF-2α and increased sVEGFR-1 production from GM-CSF-treated macrophages, with no effect on HIF-1α accumulation or VEGF production. Treatment of B16F10 melanoma-bearing mice with GM-CSF and AKB-6899 significantly reduced tumor growth compared with either drug alone. Increased levels of sVEGFR-1 mRNA, but not VEGF mRNA, were detected within the tumors of GM-CSF- and AKB-6899-treated mice, correlating with decreased tumor vascularity. Finally, the antitumor and antiangiogenic effects of AKB-6899 were abrogated when mice were simultaneously treated with a sVEGFR-1 neutralizing Ab. These results demonstrate that AKB-6899 decreases tumor growth and angiogenesis in response to GM-CSF by increasing sVEGFR-1 production from tumor-associated macrophages. Specific activation of HIF-2α can therefore decrease tumor growth and angiogenesis.

The Roles of Angiogenesis in Malignant Melanoma: Trends in Basic Science Research over the Last 100 Years

Blood vessels arose during evolution carrying oxygen and nutrients to distant organs via complex networks of blood vessels penetrating organs and tissues. Mammalian cells require oxygen and nutrients for survival, of which oxygen has a diffusion limit of 100 to 200 μm between cell and blood vessel. For growth beyond this margin, cells must recruit new blood vessels, first by vasculogenesis, where embryonic vessels form from endothelial precursors, then angiogenesis which is the sprouting of interstitial tissue columns into the lumen of preexisting blood vessels. Angiogenesis occurs in many inflammatory diseases and in many malignant disease states, including over 90% of solid tumours. Malignant melanoma (MM) is the most lethal skin cancer, highly angiogenic, highly metastatic, and refractory to all treatments. Raised serum levels of vascular endothelial growth factor (VEGF) strongly correlate MM disease progression and poor prognosis. Melanoma cells secrete several proangiogenic cytokines including VEGF-A, fibroblast growth factor (FGF-2), platelet growth factor (PGF-1), interleukin-8 (IL-8), and transforming growth factor (TGF-1) that modulate the angiogenic switch, changing expression levels during tumour transition from radial to invasive vertical and then metastatic growth. We highlight modern and historical lines of research and development that are driving this exciting area of research currently.

The role of VEGF in melanoma progression

BACKGROUND

Melanoma is the most serious skin cancer. There is an established correlation between thickness and aggressiveness of the tumor. Nevertheless, the potential value of vascular endothelial growth factor (VEGF) in correlation with tumor progression remains unresolved.

MATERIALS AND METHODS

Thirty seven paraffin blocks of cutaneous melanoma were obtained from Pathology department of Al-zahra hospital between 2005 and 2010. The sections were stained with monoclonal mouse antibodies (mAbs) against vascular endothelial growth factor A and evaluated by distribution of expression of VEGF in tumor cells as 0, 0%; 1, 1%--25%; 2, 25%--50%; 3, >50% and the staining intensity from 0 (negative) to 3 (strong). The sum of intensity score and distribution score was then calculated as the VEGF index. The relationship between VEGF expression (distribution, intensity, and index) and tumor progression (vertical and radial growth, Clark's level, and Breslow's depth) was studied. SPSS software was used to analyze the data by ANOVA, and chi-square tests.

RESULTS

51.4% of the patients showed vertical growth pattern. Mean Breslow's depth was 1.84 ± 1.79 mm. There was a significant association between growth pattern and VEGF distribution, intensity and index (P = 0.006, P = 0.005, and P = 0.001 respectively). VEGF distribution, intensity, and index all had correlation with Breslow's depth as well (ANOVA test: P = 0.003, P < 0.001, and P < 0.001 respectively) VEGF index had also correlation with Clark's level, but this was not seen for VEGF distribution and intensity.

CONCLUSION

VEGF expression (both VEGF distribution and intensity) is associated with progression of malignant melanoma. VEGF index can explain this association better.

Dual action of TGF-β induces vascular growth in vivo through recruitment of angiogenic VEGF-producing hematopoietic effector cells

The role of Transforming growth factor β (TGF-β) as a regulator of blood vessel endothelium is complicated and controversial, and the mechanisms by which TGF-β is able to induce angiogenesis in vivo are not well understood. Here we show that TGF-β causes in vivo a massive recruitment of tissue infiltrating hematopoietic cells. Concurrently, TGF-β induces strong vascular endothelial growth factor (VEGF) production in the recruited hematopoietic cells, resulting in activated angiogenesis and vascular remodeling. TGF-β also promoted abnormalities of α-smooth muscle actin-expressing pericytes on angiogenic capillaries. TGF-β-induced angiogenic effect was inhibited by a systemic treatment with VEGF-neutralizing antibodies. When studied in isolated human hematopoietic cells, physiological concentrations of TGF-β stimulated VEGF mRNA and protein expression in a dose- and time-dependent manner. This induction was p38 and p44/p42 mitogen activated kinase dependent. p38 and p44/p42 activation was also observed in vivo in TGF-β-treated angiogenic murine tissues. Taken together, our results provide a dual action mechanism by which TGF-β promotes angiogenesis in vivo via recruitment of paracrine VEGF-expressing hematopoietic effector cells. This mechanism may activate vascular growth and remodeling during inflammatory conditions and tumor growth when TGF-β activity is upregulated.

BEAM: a randomized phase II study evaluating the activity of bevacizumab in combination with carboplatin plus paclitaxel in patients with previously untreated advanced melanoma

PURPOSE

Metastatic melanoma, a highly vascularized tumor with strong expression of vascular endothelial growth factor, has an overall poor prognosis. We conducted a placebo-controlled, double-blind phase II study of carboplatin plus paclitaxel with or without bevacizumab in patients with previously untreated metastatic melanoma.

PATIENTS AND METHODS

Patients were randomly assigned in a two-to-one ratio to carboplatin (area under the curve, 5) plus paclitaxel (175 mg/m(2)) and bevacizumab (15 mg/kg; CPB) or placebo (CP) administered intravenously once every 3 weeks. Progression-free survival (PFS) was the primary end point. Secondary end points included overall survival (OS) and safety.

RESULTS

Two hundred fourteen patients (73% with M1c disease) were randomly assigned. With a median follow-up of 13 months, median PFS was 4.2 months for the CP arm (n = 71) and 5.6 months for the CPB arm (n = 143; hazard ratio [HR], 0.78; P = .1414). Overall response rates were 16.4% and 25.5%, respectively (P = .1577). With 13-month follow-up, median OS was 8.6 months in the CP arm versus 12.3 months in the CPB arm (HR, 0.67; P = .0366), whereas in an evaluation 4 months later, it was 9.2 versus 12.3 months, respectively (HR, 0.79; P = .1916). In patients with elevated serum lactate dehydrogenase (n = 84), median PFS and OS were longer in the CPB arm (PFS: 4.4 v 2.7 months; HR, 0.62; OS: 8.5 v 7.5 months; HR, 0.52). No new safety signals were observed.

CONCLUSION

The study did not meet the primary objective of statistically significant improvement in PFS with the addition of bevacizumab to carboplatin plus paclitaxel. A larger phase III study will be necessary to determine whether there is benefit to the addition of bevacizumab to carboplatin plus paclitaxel in this disease setting.

Angiogenesis and host immune response contribute to the aggressive character of non-melanoma skin cancers in renal transplant recipients

AIMS

The aim of this study was to determine the contribution of tumour angiogenesis to the aggressive growth of non-melanoma skin cancers (NMSCs) in renal transplant recipients (RTRs).

METHODS AND RESULTS

The study cohort included RTRs (n = 38) with formalin-fixed paraffin-embedded tumour samples available from first post-transplant NMSC (NMSC1) surgically excised at Christchurch Hospital, New Zealand, from 1997 to 2007. Comparable samples excised from immunocompetent individuals (ICIs) (n = 36) were selected to accommodate confounding factors. Markers of tumour angiogenesis were evaluated by immunohistochemistry, and analysed for associations with clinicopathological variables. As compared with ICIs, RTRs had a higher proportion of tumours with high microvessel density (P = 0.008), high proliferating capillary index (P < 0.0001) and low microvessel pericyte coverage index (P < 0.0001), and RTRs had a shorter cumulative second NMSC (NMSC2)-free interval (P < 0.0001). ICIs had a higher proportion of tumours with a 'marked' number of vascular endothelial growth factor (VEGF)-A-positive leukocytes than RTRs (P = 0.04), and RTRs with a 'moderate/marked' number of VEGF-A-positive leukocytes had longer cumulative NMSC2-free intervals than those with a 'minimum' number (P = 0.02).

CONCLUSIONS

This study demonstrates increased tumour angiogenesis in NMSC in RTRs, and suggests a role for VEGF-A-positive peritumoural leukocytes in suppressing NMSC development.

Prognostic Significance of Microvessel Density and Vascular Endothelial Growth Factor (VEGF) Expression in non-Hodgkin's Lymphoma

Angiogenesis has a major role in the pathogenesis of malignancies. Studies involving the role of angiogenesis have been most commonly performed in solid tumors. However, studies related to hemapoietic neoplasia and angiogenesis are relatively limited. We investigated the role of angiogenesis in non-Hodgkin's lymphomas (NHLs) and its relation with clinical and histopathologic prognostic indicators. In this respect, angiogenesis markers were evaluated in 71 patients with NHL and these were compared with other prognostic indicators including age, gender, histological grade, stage, extranodal involvement and survival. Microvessel density (MVD) using Factor VIII monoclonal antibody and vascular endothelial growth factor (VEGF) using monoclonal antibody for VEGF expression were studied in paraffin-embedded tissue samples. We did not find a significant relationship between MVD and patient characteristics including age, gender, stage, histological grade, nodal status, international prognostic index (IPI), and response to treatment. MVD was found to be greater in cases with B symptoms compared to those without B symptoms (14.6 +/- 5.7 and 11.4 +/- 5.3, respectively, p = 0.002). No significant relationship was found between VEGF and age, gender, stage, histological grade, IPI, and overall survival. The complete and partial response rate to therapy was significantly higher in VEGF-negative patients than in the VEGF-positive patients (p = 0.003). In conclusion, there appears to be a role for angiogenesis and angiogenic factors in NHLs. The combination of anti-angiogenic drugs with conventional anti-neoplastic treatment will probably be used in the future. Larger series of patients are needed to determine the prognostic value of angiogenesis in NHL.

In vitro antimetastatic effect of Changweiqing through antiinvasion of hypoxic colorectal carcinoma LoVo cells

OBJECTIVE

To investigate the in vitro effects and the primary mechanisms of Changweiqing (, CWQ) on antimetastasis and antiinvasion of hypoxic colon carcinoma cells. In addition, to provide experimental evidence for the Chinese medicinal theory of "strengthening the body's resistance to eliminate pathogenic factors" in the treatment of colorectal cancer, including its invasion and metastasis.

METHODS

First, CWQ sera were prepared with serum-pharmacology methods. Then, the modified hypoxic chamber was designed and flushed with 5% CO(2) and 95% N(2) at 37 °C to induce a hypoxic environment. The effect of CWQ serum on the viability of LoVo cells was tested with MTT cytotoxicity assay. The wound model and chamber model were established to estimate the effects of CWQ serum on migration and invasion of LoVo cells. The model for cell adhesion was established to evaluate the effect of CWQ serum on LoVo cells' adhesion. The gelatin zymography model was performed to determine the effects of CWQ serum on the activities of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9). The effects of CWQ serum on the hypoxia-inducible factor 1 α (HIF-1α) nuclear translocation and the mRNA level of vascular endothelial growth factor (VEGF) in LoVo cells were determined by Western blot and reverse transcription-polymerase chain reaction (RT-PCR) analyses, respectively.

RESULTS

CWQ inhibited LoVo cells' migration based on wound healing assay. The inhibitive effect could reach about 68.00% under hypoxic culture and about 29.87% under normoxic culture when cells were treated with 10% CWQ serum for 24 h. The results from both cell invasion and adhesion assays showed that CWQ serum could dose-dependently repress the invasion of LoVo cells and inhibit cells from adhering to extra cellular matrix (ECM). Under the hypoxic culture condition, RT-PCR analysis showed that 10% CWQ serum had down-regulated the expression of VEGF by 45.87%, and the result of Western blot analysis provided further evidence. The HIF-1α amount in the nucleus of the LoVo cells was also diminished in a dose-dependent manner, as shown by the Western blot. Gel zymogram assay revealed that CWQ serum could suppress the activities of MMP-2 and MMP-9.

CONCLUSIONS

CWQ could effectively inhibit tumor metastasis in vitro The antimetastatic effects of CWQ were associated with the inhibition of cell motility, which was evidenced by inhibition of cell invasion and adhesion. The molecular mechanisms of the inhibition of tumor invasion by CWQ were due to the reduced expression of both HIF-1α and VEGF and the suppression of MMP-2 and MMP-9 expression.

VEGFR-2 expression in human melanoma: revised assessment

Vascular endothelial growth factor (VEGF) is an angiogenic factor that also functions as an autocrine growth factor for VEGF receptor (VEGFR)-2(+) melanomas. In multiple studies, VEGFR-2 was detected by immunostaining in 78-89% of human melanoma cells, suggesting that most patients with melanoma would benefit from anti-VEGF therapy. Here, we evaluated 167 human melanoma specimens in a tissue microarray to verify the presence of VEGFR-2, but found disparities in staining with commercial antibodies A-3 and 55B11. Antibody A-3 stained melanoma cells in 79% of specimens, consistent with published results; however, we noted extensive nonspecific staining of other cells such as smooth muscle and histiocytes. In contrast, antibody 55B11 stained melanoma cells in only 7% (95% confidence interval: 3.3-11.5) of specimens. As an internal positive control for VEGFR-2 detection, vascular endothelial cells were stained with antibody 55B11 in all specimens. We compared VEGFR-2(+) and VEGFR-2(-) melanoma cell lines by immunoblotting and immunohistochemistry after small interfering RNA (siRNA) knockdown and transient overexpression of VEGFR-2 to validate antibody specificity. Immunoblotting revealed that A-3 primarily cross-reacted with several proteins in both cell lines and these were unaffected by siRNA knockdown of VEGFR-2. In contrast, 55B11 staining of VEGFR-2(+) cells was mostly eliminated by siRNA knockdown of VEGFR-2 and increased in VEGFR-2(-) melanoma cell lines following transfection to express ectopic VEGFR-2. Our results show that relatively few melanoma cells (<10%) express detectable levels of VEGFR-2, and therefore, the majority of patients with melanoma are unlikely to benefit from antiproliferative effects of anti-VEGF therapy.

Blood vessel maturation, vascular phenotype and angiogenic potential in malignant melanoma: one step forward for overcoming anti-angiogenic drug resistance?

Angiogenesis is a pivotal process for growth, invasion and spread of the majority of solid tumors including melanoma. Anti-angiogenic agents have not been systematically tested in patients with advanced melanoma. Clinical efficacy of angiogenesis inhibitors targeting endothelial cells has not been as affirmative as initially hoped and improved clinical outcomes have been observed in combination with chemotherapy or additional drugs for many types of human cancer. However, angiogenesis is not only dependent on endothelial cell invasion and proliferation, it also requires pericyte coverage of vascular sprouts for stabilization and maturation of vascular walls. Recent data suggest that pericytes might be able to confer resistance to anti-vascular endothelial growth factor (VEGF) therapy. This review will focus on the significance of the vascular phenotype but also on the impact of pericyte-mediated vessel maturation for the susceptibility to anti-angiogenic therapy, including malignant melanoma, which we identified as crucial factor regarding therapeutic efficacy.

Biomarkers: the useful and the not so useful--an assessment of molecular prognostic markers for cutaneous melanoma

Among individuals with localized (Stage I-II) melanoma, stratifying patients by a number of phenotypic variables (e.g., depth of invasion, ulceration) yields a wide range of 10-year melanoma-specific survival rates. With the possible exception of Ki-67, no molecular assessment is routinely used. However, there have been a tremendous number of studies assessing protein expression by immunohistochemistry toward the goal of better prediction of recurrence. In a previous systematic review, which required publication of multivariable prognostic models as a strict inclusion criterion, we identified 37 manuscripts that collectively reported on 62 proteins. Data for 324 proteins extracted from 418 manuscripts did not meet our inclusion criteria for that study, but are revisited here, emphasizing trends of protein expression across either melanocytic lesion progression or gradations of tumor thickness. These identified 101 additional proteins that stratify melanoma, organized according to the Hanahan and Weinberg functional capabilities of cancer.

Angiogenesis and progression in human melanoma

In tumor growth, angiogenesis, the process of new-formation of blood vessels from pre-existing ones, is uncontrolled and unlimited in time. The vascular phase is characterized by the new-formation of vascular channels that enhances tumor cell proliferation, local invasion and hematogenous metastasis. Human malignant melanoma is a highly metastatic tumor with poor prognosis, and high resistance to treatment. Parallel with progression, melanoma acquires a rich vascular network, whereas an increasing number of tumor cells express the laminin receptor, which enables their adhesion to the vascular wall, favouring tumor cell extravasation and metastases. Melanoma neovascularization has been correlated with poor prognosis, overall survival, ulceration and increased rate of relapse. Secretion of various angiogenic cytokines, i.e. VEGF-A, FGF-2, PGF-1 and -2, IL-8, and TGF-1 by melanoma cells promote the angiogenic switch and has been correlated to transition from the radial to the vertical growth phase, and to the metastatic phase. Moreover, melanoma cells overexpress alphavbeta3, alphavbeta5, alpha2beta1 and alpha5beta1 integrins and release, together with stromal cells, higher amount of metalloproteases that increasing their invasive potential and angiogenesis. Basing on these observations, different molecular targets of antiangiogenic molecules has be recognized and various antiangiogenic agents are currently in preclinical and clinical trials for melanoma.

Current systemic therapy for metastatic melanoma

Metastatic melanoma remains a lethal disease with a long-term remission rate of less than 10%. Despite many years of research, there has not been a new drug approved in this disease in over two decades. Single-agent chemotherapy is palliative in some patients and there is no advantage of combination chemotherapy or chemo-immunotherapy in randomized trials. High-dose bolus IL-2 produces some long-term remissions and is available for highly selected individuals at selected centers in the USA but is impractical for most patients. Research is ongoing in exploring novel immunotherapeutic and targeted approaches. The status of recently completed and ongoing trials is discussed in this review.

Tissue biomarkers for prognosis in cutaneous melanoma: a systematic review and meta-analysis

In the clinical management of early-stage cutaneous melanoma, it is critical to determine which patients are cured by surgery alone and which should be treated with adjuvant therapy. To assist in this decision, many groups have made an effort to use molecular information. However, although there are hundreds of studies that have sought to assess the potential prognostic value of molecular markers in predicting the course of cutaneous melanoma, at this time, no molecular method to improve risk stratification is part of recommended clinical practice. To help understand this disconnect, we conducted a systematic review and meta-analysis of the published literature that reported immunohistochemistry-based protein biomarkers of melanoma outcome. Three parallel search strategies were applied to the PubMed database through January 15, 2008, to identify cohort studies that reported associations between immunohistochemical expression and survival outcomes in melanoma that conformed to the REMARK criteria. Of the 102 cohort studies, we identified only 37 manuscripts, collectively describing 87 assays on 62 distinct proteins, which met all inclusion criteria. Promising markers that emerged included melanoma cell adhesion molecule (MCAM)/MUC18 (all-cause mortality [ACM] hazard ratio [HR] = 16.34; 95% confidence interval [CI] = 3.80 to 70.28), matrix metalloproteinase-2 (melanoma-specific mortality [MSM] HR = 2.6; 95% CI = 1.32 to 5.07), Ki-67 (combined ACM HR = 2.66; 95% CI = 1.41 to 5.01), proliferating cell nuclear antigen (ACM HR = 2.27; 95% CI = 1.56 to 3.31), and p16/INK4A (ACM HR = 0.29; 95% CI = 0.10 to 0.83, MSM HR = 0.4; 95% CI = 0.24 to 0.67). We further noted incomplete adherence to the REMARK guidelines: 14 of 27 cohort studies that failed to adequately report their methods and nine studies that failed to either perform multivariable analyses or report their risk estimates were published since 2005.