Phase II study of thalidomide in patients with metastatic malignant melanoma

VEGF/VEGFR axis and its signaling in melanoma: Current knowledge toward therapeutic targeting agents and future perspectives

Melanoma is responsible for most skin cancer-associated deaths globally. The progression of melanoma is influenced by a number of pathogenic processes. Understanding the VEGF/VEGFR axis, which includes VEGF-A, PlGF, VEGF-B, VEGF-C, and VEGF-D and their receptors, VEGFR-1, VEGFR-2, and VEGFR-3, is of great importance in melanoma due to its crucial role in angiogenesis. This axis generates multifactorial and complex cellular signaling, engaging the MAPK/ERK, PI3K/AKT, PKC, PLC-γ, and FAK signaling pathways. Melanoma cell growth and proliferation, migration and metastasis, survival, and acquired resistance to therapy are influenced by this axis. The VEGF/VEGFR axis was extensively examined for their potential as diagnostic/prognostic biomarkers in melanoma patients and results showed that VEGF overexpression can be associated with unfavorable prognosis, higher level of tumor invasion and poor response to therapy. MicroRNAs linking to the VEGF/VEGFR axis were identified and, in this review, divided into two categories according to their functions, some of them promote melanoma angiogenesis (promotive group) and some restrict melanoma angiogenesis (protective group). In addition, the approach of treating melanoma by targeting the VEGF/VEGFR axis has garnered significant interest among researchers. These agents can be divided into two main groups: anti-VEGF and VEGFR inhibitors. These therapeutic options may be a prominent step along with the modern targeting and immune therapies for better coverage of pathological processes leading to melanoma progression and therapy resistance.

Targeting Epigenetic Modifications in Uveal Melanoma

Uveal melanoma (UM), the most common intraocular malignancy in adults, is a rare subset of melanoma. Despite effective primary therapy, around 50% of patients will develop the metastatic disease. Several clinical trials have been evaluated for patients with advanced UM, though outcomes remain dismal due to the lack of efficient therapies. Epigenetic dysregulation consisting of aberrant DNA methylation, histone modifications, and small non-coding RNA expression, silencing tumor suppressor genes, or activating oncogenes, have been shown to play a significant role in UM initiation and progression. Given that there is no evidence any approach improves results so far, adopting combination therapies, incorporating a new generation of epigenetic drugs targeting these alterations, may pave the way for novel promising therapeutic options. Furthermore, the fusion of effector enzymes with nuclease-deficient Cas9 (dCas9) in clustered regularly interspaced short palindromic repeats (CRISPR) associated protein 9 (Cas9) system equips a potent tool for locus-specific erasure or establishment of DNA methylation as well as histone modifications and, therefore, transcriptional regulation of specific genes. Both, CRISPR-dCas9 potential for driver epigenetic alterations discovery, and possibilities for their targeting in UM are highlighted in this review.

Efficacy and Safety of Thalidomide for Chemotherapy-induced Nausea and Vomiting

Purpose: A substantial number of cancer patients discontinue chemotherapy due to severe chemotherapy-induced nausea and vomiting (CINV). This study aimed to evaluate the efficacy and safety of thalidomide (THD) in CINV. Methods: We searched different databases to identify related studies that investigated the efficacy and safety of THD in CINV. The primary outcomes were CINV in the acute (0-24 h), delayed (24-120 h), and overall (0-120 h) phases, respectively. The secondary outcomes were the safety of THD and the patients' quality of life (QOL). Results: Fourteen randomized control trials (RCTs) including 1744 patients (42% male) reported the risk ratio (RR) and 95%CI of the THD group versus control group in reducing nausea and vomiting. Meta-analysis showed that THD statistically enhanced the complete response rate of nausea and vomiting in the delayed (nausea: RR = 1.69, 95%CI: 1.47-1.94; vomiting: RR = 1.38, 95%CI: 1.26-1.51) and overall phases (nausea: RR = 1.54, 95%CI: 1.31-1.81; vomiting: RR = 1.31, 95%CI: 1.18-1.46). Furthermore, subgroup analysis based on THD dosage (100 vs 200 mg/day) demonstrated no statistical significance with respect to overlapping 95%CI. Thirty studies monitored the adverse events (AEs) of THD, all under grade 3 based on the CTCAE criteria. We compared the eight most common AEs; sedation, constipation, and drowsiness/dizziness were slightly frequent compared with controls. Conclusion: THD is an effective adjuvant and a potential alternative in reducing delayed and overall CINV. Other regimens might be added for CINV during the acute phase.

Uveal melanoma: From diagnosis to treatment and the science in between

Melanomas of the choroid, ciliary body, and iris of the eye are collectively known as uveal melanomas. These cancers represent 5% of all melanoma diagnoses in the United States, and their age-adjusted risk is 5 per 1 million population. These less frequent melanomas are dissimilar to their more common cutaneous melanoma relative, with differing risk factors, primary treatment, anatomic spread, molecular changes, and responses to systemic therapy. Once uveal melanoma becomes metastatic, therapy options are limited and are often extrapolated from cutaneous melanoma therapies despite the routine exclusion of patients with uveal melanoma from clinical trials. Clinical trials directed at uveal melanoma have been completed or are in progress, and data from these well designed investigations will help guide future directions in this orphan disease. Cancer 2016;122:2299-2312. © 2016 American Cancer Society.

Systemic treatment of metastatic uveal melanoma: review of literature and future perspectives

Up to 50% of patients with uveal melanoma develop metastatic disease with poor prognosis. Regional, mainly liver-directed, therapies may induce limited tumor responses but do not improve overall survival. Response rates of metastatic uveal melanoma (MUM) to systemic chemotherapy are poor. Insights into the molecular biology of MUM recently led to investigation of new drugs. In this study, to compare response rates of systemic treatment for MUM we searched Pubmed/Web of Knowledge databases and ASCO website (1980-2013) for "metastatic/uveal/melanoma" and "melanoma/eye." Forty studies (one case series, three phase I, five pilot, 22 nonrandomized, and two randomized phase II, one randomized phase III study, data of three expanded access programs, three retrospective studies) with 841 evaluable patients were included in the numeric outcome analysis. Complete or partial remissions were observed in 39/841 patients (overall response rate [ORR] 4.6%; 95% confidence intervals [CI] 3.3-6.3%), no responses were observed in 22/40 studies. Progression-free survival ranged from 1.8 to 7.2, median overall survival from 5.2 to 19.0 months as reported in 21/40 and 26/40 studies, respectively. Best responses were seen for chemoimmunotherapy (ORR 10.3%; 95% CI 4.8-18.7%) though mainly in first-line patients. Immunotherapy with ipilimumab, antiangiogenetic approaches, and kinase inhibitors have not yet proven to be superior to chemotherapy. MEK inhibitors are currently investigated in a phase II trial with promising preliminary data. Despite new insights into genetic and molecular background of MUM, satisfying systemic treatment approaches are currently lacking. Study results of innovative treatment strategies are urgently awaited.

Oncogenic CUL4A determines the response to thalidomide treatment in prostate cancer

Thalidomide is experimentally used to treat various human cancers; however, clinical responses to thalidomide are sporadic. Here we demonstrate that CUL4A plays an oncogenic role in prostate cancer development and prostate cancer cells with higher level of CUL4A are particularly sensitive to thalidomide treatment. We show that CUL4A is frequently overexpressed in human primary prostate cancer and cell lines. Notably, subjects with tumors that highly expressed CUL4A had poor overall survival. CUL4A downregulation inhibited cell proliferation and induced apoptosis in vitro and in vivo, whereas CUL4A overexpression transformed human normal prostate epithelial cells and promoted invasion, which was attenuated by the extracellular signal-regulated kinase (ERK) inhibitor. We further show that the sensitivity to thalidomide is positively correlated with CUL4A expression in a panel of prostate cell lines. Ectopic CUL4A expression greatly enhanced sensitivity to thalidomide, while its downregulation conferred resistance to this drug. Mechanistically, thalidomide decreased CUL4A in a time- and dose-dependent manner, consequently leading to inaction of ERK pathway. Finally, we show that cereblon level is correlated with CUL4A expression and downregulated in thalidomide-resistant prostate cancer cell. Our results offer the first evidence that CUL4A is a potential therapeutic target for prostate cancer and may serve as a biomarker for assessing prognosis of human prostate cancer and response to thalidomide treatment.

A phase II study of gefitinib in patients with metastatic melanoma

Gefitinib is an inhibitor of the epidermal growth factor receptor, which is frequently expressed on both choroidal and nonchoroidal melanoma cells. We evaluated the clinical efficacy of gefitinib in patients with metastatic melanoma. Patients with stage IV or unresectable stage III melanoma and Zubrod performance status of less than or equal to 2 were eligible. Previous systemic treatment for metastatic disease was required. The dose of oral gefitinib was 250 mg administered daily, and tumor response was evaluated every 6 weeks. Forty-six patients with nonchoroidal melanoma and six with choroidal melanoma were treated, and 48 were evaluable for response. The median age was 62.5 years. Forty-one patients (79%) had stage M1c disease. There were no drug-related grade 4 or 5 adverse events, and fatigue was the only grade 3 adverse event that occurred in more than 5% of patients. Two patients (4%) had partial responses and 13 patients (27%) had disease stabilization. The two responders had a median duration of response of 10.9 months. The median overall progression-free survival was 1.4 months and the median overall survival was 9.7 months. Among the patients with sufficient tissues obtained before and 6 weeks after starting gefitinib administration, there were no notable trends in the changes of the tumoral expression of p-ERK1/2, p-AKT, PAK1, and serum levels of vascular endothelial growth factor or IL-8 with treatment. We concluded that gefitinib was well tolerated but had minimal clinical efficacy as a single-agent therapy for unselected patients with metastatic melanoma.

Results of a multicenter, randomized, double-blind phase 2/3 study of lenalidomide in the treatment of pretreated relapsed or refractory metastatic malignant melanoma

BACKGROUND

The results of an international, multicenter, randomized, double-blind, controlled study assessing the efficacy and safety of lenalidomide treatment in patients with refractory stage IV metastatic malignant melanoma are reported.

METHODS

The study compared treatment with lenalidomide (25 mg/d on Days 1-21 of a 28-day cycle) to placebo in 306 patients with metastatic malignant melanoma. Treatment was continued until progression of disease or unacceptable toxicity.

RESULTS

There were no significant differences between lenalidomide and placebo in overall survival (median 5.9 months vs 7.4 months, respectively; P = .32), time to progression (median 3.0 months vs 2.1 months; P = .19), or Response Evaluation Criteria in Solid Tumors tumor response (5.3% vs 5.8%; P = .82). None of the patients given placebo discontinued treatment because of treatment-related adverse events, compared with 4.6% of those treated with lenalidomide. Treatment-related myelosuppression was observed in 2.0% of patients treated with placebo and 7.3% of patients treated with lenalidomide.

CONCLUSIONS

This study showed that treatment with lenalidomide (25 mg/d) has a manageable safety profile in patients with previously treated metastatic malignant melanoma but no benefit in tumor response, time to progression, or overall survival in these patients. Future trials for treatment of metastatic malignant melanoma with lenalidomide should focus on its use in combination therapies.

Phase 2 trial of combination thalidomide plus temozolomide in patients with metastatic malignant melanoma: Southwest Oncology Group S0508

BACKGROUND

In limited institution phase 2 studies, thalidomide and temozolomide has yielded response rates (RRs) up to 32% for advanced melanoma, leading to the use of this combination as "standard" by some. We conducted a multicenter phase 2 trial to better define the clinical efficacy of thalidomide and temozolomide and the immune modulatory effects of thalidomide, when combined with temozolomide, in patients with metastatic melanoma.

METHODS

Patients must have had stage IV cutaneous melanoma, no active brain metastases, Zubrod PS 0-1, up to 1 prior systemic therapy excluding thalidomide, temozolomide, or dacarbazine, adequate organ function, and given informed consent. The primary endpoint was 6-month progression-free survival (PFS). Secondary endpoints included overall survival (OS), RR, toxicities, and assessment of relationships between biomarkers and clinical outcomes. Patients received thalidomide (200 mg/d escalated to 400 mg/d for patients <70, or 100 mg/d escalated to 250 mg/d for patients > or =70) plus temozolomide (75 mg/m(2)/d x 6 weeks, and then 2 weeks rest).

RESULTS

Sixty-four patients were enrolled; 2 refused treatment. The 6-month PFS was 15% (95% confidence interval [CI], 6%-23%), the 1-year OS was 35% (95% CI, 24%-47%), and the RR was 13% (95% CI, 5%-25%), all partial. One treatment-related death occurred from myocardial infarction; 3 other grade 4 events occurred, including pulmonary embolism, neutropenia, and central nervous system (CNS) ischemia. There was no significant correlation between biomarkers and PFS or OS.

CONCLUSIONS

This combination of thalidomide and temozolomide does not appear to have a clinical benefit that exceeds dacarbazine alone. We would not recommend it further for phase 3 trials or for standard community use.

Results of a multicenter, randomized, double-blind, dose-evaluating phase 2/3 study of lenalidomide in the treatment of metastatic malignant melanoma

BACKGROUND

There are currently no systemic treatments for stage IV melanoma, which have been proven in randomized trials to benefit overall survival (OS). Lenalidomide has efficacy against melanoma in animal models and safety in phase 1 trials. The authors reported the results of a phase 2/3 study comparing the safety and efficacy of 2 doses of lenalidomide in patients with relapsed metastatic melanoma disease refractory to previous treatment with dacarbazine, temozolomide, interleukin-2, or interferon-alpha.

METHODS

A total of 294 patients were randomized to oral lenalidomide at 5 mg or 25 mg dose. Tumor response, time to progression, and OS were evaluated. Treatment continued until disease progression or unacceptable adverse events.

RESULTS

No significant differences in response rate, OS, or time to progression were observed between lenalidomide 25 mg versus 5 mg (overall response rate: 5.5% vs 3.4%, P = .38; median OS: 6.8 months vs 7.2 months, P = .71; and median time to progression: 2.2 months vs 1.9 months, P = .24). Myelosuppression was observed in 37.0% of patients in the 25 mg group and 13.7% of patients in the 5 mg group. Treatment-related serious adverse events were seen in 39.0% of patients at the 25 mg dose and 35.4% of patients at the 5 mg dose.

CONCLUSIONS

Despite the occurrence of treatment-related serious adverse events, approximately 80% of patients continued treatment. The higher dose of lenalidomide did not improve response rate, time to progression, or OS of patients with relapsed/refractory stage IV melanoma. A parallel placebo-controlled study has been conducted to further assess the efficacy of lenalidomide in stage IV melanoma patients.

The role of angiogenesis in solid tumours: an overview

Angiogenesis is the physiological process of the formation of new blood vessels from pre-existing ones. Multiple molecules regulate angiogenesis, such as the vascular endothelial growth factor, angiopoietins, the fibroblast growth factor, the platelet-derived growth factor and the transforming growth factor-beta. Angiogenesis plays an important role in the growth, progression and metastasis of a tumour. Inhibiting the angiogenic process or targeting existing tumour vessels can be used for treatment of tumours as an alternative or in parallel with conventional chemotherapy. Many anti-angiogenic factors are under investigation and some are already being used in clinical practice with various results.

Molecular-targeted therapy in malignant melanoma

Malignant melanoma is a deadly disease in which standard treatment options have remained remarkably static over the past 30 years. Recent discoveries have expanded the understanding of the molecular processes critical to melanomagenesis. During this same time period, therapeutic agents have been developed that target these processes, leading to an explosion of preclinical research. Several agents that have shown promise in the preclinical setting have now entered clinical trials. To date, the success of these molecularly targeted approaches as single agents has been limited. Although more encouraging results have been seen when these agents have been used in combination with cytotoxic therapy, the specific contribution of the targeted agents to the observed anti-tumor effects remains to be established in randomized controlled Phase III trials. This article presents a review of the limitations of current therapy, a description of key pathogenic mechanisms for which inhibitors exist and a summary of therapeutic trials of molecularly targeted agents in this disease.

Novel therapeutics for the treatment of metastatic melanoma

Metastatic malignant melanoma is an incurable disease with a median survival of 8.5 months and a probability of surviving 5 years after the diagnosis of less than 5%. To date, no systemic therapy has meaningfully changed these survival end points. Currently, in the USA the FDA has approved three agents for the treatment of metastatic melanoma: hydroxyurea, dacarbazine and interleukin-2. None of these have demonstrated a meaningfully prolonged survival of patients with metastatic melanoma. Therefore, a number of innovative therapeutic strategies have been pursued to improve outcomes, including immune therapy, tyrosine kinase inhibitors and angiogenesis inhibitors. Herein, we review some of the recent advances in novel therapeutic developments for the treatment of metastatic melanoma.

A phase II study of thalidomide in patients with brain metastases from malignant melanoma

INTRODUCTION

Brain metastases develop in nearly half of the patients with advanced melanoma and in 15 to 20% of these patients CNS is the first site of relapse. Overall median survival is short, ranging from 2 to 4 months. Thalidomide has antiangiogenic and immunomodulatory effects. Results obtained in prior trials indicate that Thalidomide acts as a cytostatic agent in metastatic melanoma. We evaluated single agent antitumour activity and toxicity of Thalidomide in a phase II setting in patients with brain metastases associated with metastatic melanoma.

MATERIAL AND METHODS

Patients with measurable metastatic melanoma in progression and with PS < or = 2 were enrolled in the study. Thalidomide was given orally. Dose was escalated over 4 weeks from 100 mg/day to 400 mg/day. Primary objective of the study was to determine response rate, according to RECIST. Secondary objectives were to estimate time to progression, overall survival and to evaluate tolerability of the regimen.

RESULTS

Twenty five men and 11 women were enrolled in the study, median age 48 years. Among 36 eligible patients 35 were evaluable for response. None of the patients obtained a response in brain metastases. Three patients obtained a partial response in extracranial lesions. Toxicity was acceptable and manageably. Median time to progression and overall survival time was 1.7 and 3.1 months, respectively.

CONCLUSION

There were no objective responses in the brain but single agent Thalidomide has some activity in melanoma patients with brain metastases. It has encouraged us to investigate Thalidomide in combination with Temozolomide, a very lipophilic agent, in this group of patients.

Translational research in melanoma

Current treatment of malignant melanoma exemplifies not only the need for translational research but also many of the challenges of moving from bench to bedside. Melanoma remains unique among solid tumors in that its treatment primarily is surgical. Radiation is of limited benefit, and chemotherapy has been disappointing in both the adjuvant and metastatic settings. This leaves clinicians with few options for reducing the chance of recurrence after surgery and for treating unresectable disease. With this in mind, there has been a fervent attempt to identify novel approaches to melanoma therapy and translate them into clinical use.

Preliminary results of the combination of bevacizumab and weekly Paclitaxel in advanced melanoma

BACKGROUND

Pretreated advanced melanoma is a poor prognosis scenario with few, if any, active therapeutic options. The antibody against vascular endothelial growth factor, bevacizumab, has demonstrated increased activity in combination with chemotherapy in many tumors. We intended to evaluate the activity of the combination of weekly paclitaxel and bevacizumab in previously treated metastatic melanoma.

PATIENTS AND METHODS

Patients with previously treated metastatic melanoma received paclitaxel 70 mg/m(2) weekly and bevacizumab 10 mg/kg biweekly for 5 consecutive weeks every 6 weeks.

RESULTS

Twelve patients were treated. Two patients (16.6%) achieved a partial response and 7 patients (58.3%) stable disease. Responses were seen in soft tissue, lung and brain metastases. Median disease-free and overall survival times were 3.7 and 7.8 months, respectively. Treatment was well tolerated. Main toxicities were grade 3 asymptomatic lymphopenia in 6 patients, grade 3 leucopenia in 2 patients, and grade 3 thrombocytopenia in 1 patient.

CONCLUSIONS

Our preliminary results suggest that the combination of bevacizumab and weekly paclitaxel is active and safe in patients with metastatic melanoma, warranting further investigation.

NF-kappaB as a molecular target in the therapy of pancreatic carcinoma

The constitutive activation of the transcription factor nuclear-factor kappa B (NF-kappaB) is a hallmark of many highly malignant tumours such as the pancreatic ductal adenocarcinoma and accounts for profound chemoresistance. Inhibition of NF-kappaB activation has been shown to be a useful strategy for increasing the sensitivity towards cytostatic drug treatment in vitro and in vivo. Moreover, various pharmacological substances (e.g. thalidomide, bortezomib, sulphasalazine) have already entered clinical studies partially showing promising results for certain types of cancer. Further studies will be needed, in particular for pancreatic ductal adenocarcinoma, to evaluate the therapeutic efficacy of appropriate combinations of a NF-kappaB inhibitor and cytostatic drugs.

Early experience with novel immunomodulators for cancer treatment

Immunotherapy involves the treatment of cancer by modification of the host-tumour relationship. It is now known that this relationship is quite complex and only some of the interactions have been elucidated. Early attempts at immunotherapy, such as Coley's toxins, were undertaken without an understanding of the processes mediating the effects. With a better understanding of the immunology of this anticancer response, recent trials have focussed on certain aspects of the process to stimulate an antitumour response. In this review, the authors discuss a number of novel biological response modifiers that work as general stimulants of the immune system, through varied mechanisms including induction of stimulatory cytokines (such as IFN-alpha, TNF-alpha and IL-12) and activation of T cells and the antigen-presenting dendritic cells. These compounds include Toll-like receptor agonists, several of which are in clinical trials at present. In addition to immunomodulatory activity, some compounds such as 5,6-dimethylxanthenone-4-acetic acid (DMXAA) and thalidomide and its analogues also target existing or developing tumour vasculature. Some of these compounds have single-agent activity in clinical trials, while others such as DMXAA have shown promise in combination with chemotherapy without increasing toxicity. Lactoferrin is another compound that has shown clinical activity with low toxicity. At present, accepted indications for immunotherapy are limited to a few cancers such as renal cell carcinoma and melanoma. This paper looks at some of the reasons for the limited impact of immunotherapy so far and suggest possible avenues for further research with a greater likelihood of success.

A phase II trial of thalidomide and cyclophosphamide in patients with recurrent or refractory pediatric malignancies

BACKGROUND

Previous clinical and pre-clinical research has demonstrated synergy between anti-angiogenic agents and cytotoxic chemotherapy. This trial was undertaken to investigate whether the combination of cyclophosphamide and thalidomide would be active against pediatric tumors.

PROCEDURE

Patients with pediatric malignancies who had no remaining conventional therapeutic options were recruited from January 1999 to May 2001. They received thalidomide (6-12 mg/kg po every day; maximum daily dose 800 mg) and cyclophosphamide (1,200 mg/m2 IV every 28 days).

RESULTS

Twenty-seven patients were enrolled on the study. Seventeen were male and 10 were female. Median age at the time of registration was 15 years (range 1-54 years). The median number of prior treatment regimens was four. Twenty-one patients were evaluable for response; 1 had a partial response (Hodgkin disease), 1 demonstrated stable disease (neuroendocrine tumor), and 19 had progressive disease. The most common toxicities were hematological (leukocytopenia and neutropenia) and gastrointestinal. One patient experienced a grade 3 rash. Fatigue and daytime somnolence were variable. No peripheral neuropathy was observed.

CONCLUSION

The combination of thalidomide and cyclophosphamide as described herein has a modest and tolerable toxicity profile but little evidence of efficacy.

A phase II study of ABT-510 (thrombospondin-1 analog) for the treatment of metastatic melanoma

OBJECTIVES

Thrombospondins are natural inhibitors of angiogenesis, tumor metastases, and tumor growth (melanoma). ABT-510 is a synthetic analog of thrombospondin-1, well tolerated in phase I studies. We conducted a phase II trial evaluating the clinical efficacy of ABT-510 and its effects on biomarkers of angiogenesis and immunity in patients with metastatic melanoma (MM).

PATIENTS AND METHODS

A 2-stage phase II clinical trial was conducted to assess the clinical efficacy, safety, and pharmacodynamic effects (angiogenesis and immunity) of ABT-510 in patients with stage IV melanoma. The primary endpoint was 18-week treatment failure rate. Patients self-administered 100 mg of ABT-510 subcutaneously twice daily. Blood samples were collected at baseline and every 3 weeks while on therapy. Eligible patients demonstrated measurable disease, good performance status and no evidence of intracranial metastases. Correlative laboratory studies evaluated biomarkers of angiogenesis and immunity.

RESULTS

Twenty-one patients were enrolled. Most patients were stage M1c (71%) and all had prior therapy for MM. Only 3 of the first 20 patients enrolled were progression free and on treatment at 18 weeks resulting in early termination of the study. Decreases in peripheral blood VEGF-A levels and VEGF-C levels, and CD146 and CD34/133 counts relative to pretreatment were detected. Limited changes in antitumor T cell immunity were observed.

CONCLUSIONS

ABT-510 therapy administered at 100 mg twice/day in patients with MM did not demonstrate definite clinical efficacy. Further dose escalation or combination with cytotoxic therapy may be more effective therapeutically.

Malignant melanoma in the 21st century, part 2: staging, prognosis, and treatment

Critical to the clinical management of a patient with malignant melanoma is an understanding of its natural history. As with most malignant disorders, prognosis is highly dependent on the clinical stage (extent of tumor burden) at the time of diagnosis. The patient's clinical stage at diagnosis dictates selection of therapy. We review the state of the art in melanoma staging, prognosis, and therapy. Substantial progress has been made in this regard during the past 2 decades. This progress is primarily reflected in the development of sentinel lymph node biopsies as a means of reducing the morbidity associated with regional lymph node dissection, increased understanding of the role of neoangiogenesis in the natural history of melanoma and its potential as a treatment target, and emergence of innovative multimodal therapeutic strategies, resulting in significant objective response rates in a disease commonly believed to be drug resistant. Although much work remains to be done to improve the survival of patients with melanoma, clinically meaningful results seem within reach.

Clinical implications of angiogenesis in cancers

Angiogenesis plays an important role in the growth and progression of cancer. The regulation of tumor angiogenesis depends on a net balance of angiogenic factors and antiangiogenic factors, which are secreted by both tumor cells and host-infiltrating cells. Numerous studies have indicated that assessment of angiogenic activity by either microvessel density or expression of angiogenic factors in cancer can provide prognostic information independent of conventional clinicopathological factors such as tumor staging. Some studies also suggested that assessment of tumor angiogenesis may predict cancer response to chemotherapy or radiotherapy. However, the most important clinical implication of tumor angiogenesis is the development of a novel strategy of anticancer therapy targeting tumor vessels instead of cancer cells. Antiangiogenic therapy aims to inhibit the growth of tumor, and current evidence suggests that it works best in combination with conventional cytotoxic chemotherapy. Recently, a monoclonal antibody against vascular endothelial growth factor, which is one of the most potent angiogenic factors, has been approved for clinical use in colorectal cancer patients after a clinical trial confirmed that combining the antibody with standard chemotherapy regimen could prolong patient survival. The clinical implications of angiogenesis in cancer are reviewed in this article.

Novel treatment strategies for malignant melanoma: a new beginning?

Malignant melanoma is one of the most common cancer types among the Caucasian population. While the prognosis is excellent for patients diagnosed at an early stage and treated by adequate surgery, unresectable or advanced metastatic diseases shrink the overall survival at 5 years dramatically to less than 10%. For disseminated malignant melanoma, the appropriate systemic medical treatment is still controversial. Fortunately, progress in the molecular biology and in the understanding of pathogenesis has been made recently and should in the near future translate into molecular-based therapeutic strategies. In this review, we briefly describe the status of current treatment strategies and existing standards for malignant melanoma. We will focus on the new and emerging compounds including recent developments of targeted therapy such as antiangiogenic and immunomodulatory drugs, Bcl-2 antisense therapy, raf kinase inhibitors, heat shock protein modulators, anti-cytotoxic T lymphocyte-associated antigen (CTLA)-4 monoclonal antibody and finally PARP and proteasome inhibitors.

Anti-angiogenic drugs: from bench to clinical trials

Angiogenesis, the generation of new capillaries through a process of pre-existing microvessel sprouting, is under stringent control and normally occurs only during embryonic and post-embryonic development, reproductive cycle, and wound repair. However, in many pathological conditions (solid tumor progression, metastasis, diabetic retinopathy, hemangioma, arthritis, psoriasis and atherosclerosis among others), the disease appears to be associated with persistent upregulated angiogenesis. The development of specific anti-angiogenic agents arises as an attractive therapeutic approach for the treatment of cancer and other angiogenesis-dependent diseases. The formation of new blood vessels is a complex multi-step process. Endothelial cells resting in the parent vessels are activated by an angiogenic signal and stimulated to synthesize and release degradative enzymes allowing endothelial cells to migrate, proliferate and finally differentiate to give rise to capillary tubules. Any of these steps may be a potential target for pharmacological intervention. In spite of the disappointing results obtained initially in clinical trials with anti-angiogenic drugs, recent reports with positive results in phases II and III trials encourage expectations in their therapeutic potential. This review discusses the current approaches for the discovery of new compounds that inhibit angiogenesis, with emphasis on the clinical developmental status of anti-angiogenic drugs.

Molecularly targeted therapy for melanoma

Effective therapy for melanoma remains an unmet goal, with most traditional therapies representing inadequate trade-offs among the several goals of specificity, efficacy, and toxicity. Targeted molecular therapeutics are tailored to genetic abnormalities that are associated with tumor progression. Modulation of aberrant signaling pathways in cancer cells has the potential to provide more effective and potentially nontoxic therapy for a broad range of cancers, including melanoma. Among the possible targets in melanoma are the Ras-MAPK and PI3K/AKT signal transduction pathways, the proteasome, histone deacetylases, methyltransferases, and melanoma-induced angiogenesis.