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Angiogenesis is a constant hallmark of multiple myeloma (MM) progression and involves direct production of angiogenic cytokines by plasma cells and their induction within the bone marrow microenvironment. This article summarizes the more recent literature data concerning the employment of anti-angiogenic therapeutic agents actually used in preclinical models and clinical settings for the treatment of multiple myeloma.

Thalidomide is a drug with interesting therapeutic properties but also with severe side effects which require a careful and monitored use. Potential immunomodulatory, antiinflammatory, anti-angiogenic and sedative properties make thalidomide a good candidate for the treatment of several diseases such as multiple myeloma. Through an increase in the degradation of TNFα-mRNA, thalidomide reduces the production of TNFα by monocytes and macrophages stimulated by lipopolysaccharide or by T lymphocytes induced by mitogenic stimuli. The decreased level of TNFα alters the mechanisms of intracellular transduction by preventing the activation of NF-kB and by decreasing the synthesis of proteins, in particular IL-6, involved in cell proliferation, inflammation, angiogenesis and protection from apoptosis. Furthermore, thalidomide affects VEGF levels by down-regulating its expression. Nowadays, new safer and less toxic drugs, analogs of thalidomide, are emerging as beneficial for a more targeted treatment of multiple myeloma and several other diseases such as Crohn';s disease, rheumatoid arthritis, sarcoidosis, erythema nodosum leprosum, graft-versus-host disease., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Multiple myeloma (MM) is a clonal B-cell malignancy characterized by an accumulation of clonal plasma cells (PC) in the bone marrow (BM) leading to bone destruction and BM failure. Despite recent advances in pharmacological therapy, MM remains a largely incurable pathology. Therefore, novel effective and less toxic agents are urgently necessary. In the last few years, pomegranate has been studied for its potential therapeutic properties including treatment and prevention of cancer. Pomegranate juice (PGJ) contains a number of potential active compounds including organic acids, vitamins, sugars, and phenolic components that are all responsible of the pro-apoptotic effects observed in tumor cell line. The aim of present investigation is to assess the antiproliferative and antiangiogenic potential of the PGJ in human multiple myeloma cell lines. Our data demonstrate the anti-proliferative potential of PGJ in MM cells; its ability to induce G0/G1 cell cycle block and its anti-angiogenic effects. Interestingly, sequential combination of bortezomib/PGJ improved the cytotoxic effect of the proteosome inhibitor. We investigated the effect of PGJ on angiogenesis and cell migration/invasion. Interestingly, we observed an inhibitory effect on the tube formation, microvessel outgrowth aorting ring and decreased cell migration and invasion as showed by wound-healing and transwell assays, respectively. Analysis of angiogenic genes expression in endothelial cells confirmed the anti-angiogenic properties of pomegranate. Therefore, PGJ administration could represent a good tool in order to identify novel therapeutic strategies for MM treatment, exploiting its anti-proliferative and anti-angiogenic effects. Finally, the present research supports the evidence that PGJ could play a key role of a future therapeutic approach for treatment of MM in order to optimize the pharmacological effect of bortezomib, especially as adjuvant after treatment., Competing Interests: The authors declare no conflict of interest.

Angiogenesis is associated with the progression of multiple myeloma (MM). Wogonin is an active mono-flavonoid with remarkable antitumor activity. However, its impact on MM-stimulated angiogenesis remains largely unknown. Here, we demonstrated that wogonin decreased expression and secretion of pro-angiogenic factors in MM cells via c-Myc/HIF-1α signaling axis, reducing MM-stimulated angiogenesis and MM cell proliferation in vivo. Overexpression of c-Myc in MM cells disrupted the balance between VHL SUMOylation and ubiquitination, and thus inhibited proteasome-mediated HIF-1α degradation. Impaired function of VHL ubiquitination complex in c-Myc-overexpressing cells was fully reversed by wogonin treatment via increasing HIF-1α-VHL interaction and promoting HIF-1α degradation. Collectively, our in vitro and in vivo studies reveal for the first time that wogonin represses MM-stimulated angiogenesis and tumor progression via c-Myc/VHL/HIF-1α signaling axis.

Vascular endothelial growth factor (VEGF) has been reported not only to induce angiogenesis within the bone marrow, but also directly stimulate the proliferation and survival of multiple myeloma cells, thus being involved in the development and progression of this second most common hematological malignancy. We, along with others, have found that pigment epithelium-derived factor (PEDF) has anti-angiogenic and anti-vasopermeability properties both in cell culture and animal models by counteracting the biological actions of VEGF. However, effects of PEDF on VEGF-exposed myeloma cells remain unknown. In this study, we examined whether and how PEDF could inhibit the VEGF-induced proliferation and survival of myeloma cells. PEDF, a glutathione peroxidase mimetic, ebselen, or an inhibitor of NADPH oxidase, diphenylene iodonium significantly inhibited the VEGF-induced reactive oxygen species (ROS) generation, increase in anti-apoptotic and growth-promoting factor, myeloid cell leukemia 1 (Mcl-1) expression, and proliferation in U266 myeloma cells. VEGF blocked apoptosis of multiple myeloma cells isolated from patients, which was prevented by PEDF. PEDF also reduced p22phox levels in VEGF-exposed U266 cells. Furthermore, overexpression of dominant-negative human Rac-1 mutant mimicked the effects of PEDF on ROS generation and Mcl-1 expression in U266 cells. Our present study suggests that PEDF could block the VEGF-induced proliferation and survival of multiple myeloma U266 cells through its anti-oxidative properties via suppression of p22phox, one of the membrane components of NADPH oxidase. Suppression of VEGF signaling by PEDF may be a novel therapeutic target for multiple myeloma., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Angiogenesis is a constant hallmark of multiple myeloma (MM) progression and has prognostic potential. The pathophysiology of MM-induced angiogenesis involves both direct production of angiogenic cytokines by plasma cells and their induction within the bone marrow microenvironment. An improved understanding of the importance of angiogenesis-related signaling in MM has allowed for the rational use of antiangiogenic therapies in this tumor. This review article summarizes the literature data concerning the employment of the most important antiangiogenic therapeutic agents actually used in preclinical models and clinical settings for the treatment of MM.

Research on the formation of new blood vessels (angiogenesis) in general and vascular endothelial growth factor (VEGF) in particular is a major focus in biomedicine and has led to the clinical approval of the monoclonal anti- VEGF antibody bevazicumab; and the second-generation multitargeted receptor kinase inhibitors (RTKIs) sorafenib, sunitinib, and pazopanib. Although these agents show significant preclinical and clinical anti-cancer activity, they prolong overall survival of cancer patients for only months, followed by a restoration of tumor growth and progression. Therefore, there is a clear need to increase our understanding of tumor angiogenesis and the development of resistance. In this review we discuss up-to-date knowledge on mechanisms of tumor angiogenesis, and summarize preclinical and clinical data on existing and potential future anti-angiogenic agents and treatment strategies for Multiple Myeloma (MM) and other hematologic and solid malignancies.

Previous studies have established a role of vascular-disrupting agents as anti- cancer agents. Plinabulin is a novel vascular-disrupting agent that exhibits potent interruption of tumor blood flow because of the disruption of tumor vascular endothelial cells, resulting in tumor necrosis. In addition, plinabulin exerts a direct action on tumor cells, resulting in apoptosis. In the present study, we examined the anti-multiple myeloma (MM) activity of plinabulin. We show that low concentrations of plinabulin exhibit a potent antiangiogenic action on vascular endothelial cells. Importantly, plinabulin also induces apoptotic cell death in MM cell lines and tumor cells from patients with MM, associated with mitotic growth arrest. Plinabulin-induced apoptosis is mediated through activation of caspase-3, caspase-8, caspase-9, and poly(ADP-ribose) polymerase cleavage. Moreover, plinabulin triggered phosphorylation of stress response protein JNK, as a primary target, whereas blockade of JNK with a biochemical inhibitor or small interfering RNA strategy abrogated plinabulin-induced mitotic block or MM cell death. Finally, in vivo studies show that plinabulin was well tolerated and significantly inhibited tumor growth and prolonged survival in a human MM.1S plasmacytoma murine xenograft model. Our study therefore provides the rationale for clinical evaluation of plinabulin to improve patient outcome in MM.

Survival of patients affected by Multiple Myeloma (MM), a B-cell tumor of malignant plasma cells, has dramatically improved, owing to the recent introduction of the proteasome inhibitor (PI) Bortezomib and of the immunomodulatory drugs (IMiDs). This major advance originates from accumulating knowledge on MM biology, leading to the development of drugs targeting not only MM cells, but also their microenvironment. Indeed, the disease develops as a result of genetic abnormalities and of reciprocal interactions between MM cells and the permissive BM microenvironment, which delivers growth- and pro-survival signals and confers resistance to drugs. As for solid tumors, bone marrow (BM) angiogenesis is emerging as a critical component of MM development and progression, and hence as an attractive therapeutic target for the disease. The patho-physiology of MM associated angiogenesis is complex and involves a plethora of soluble factors, cellular players and mechanisms. Moreover, the hypoxic microenvironment inside the BM might significantly contribute to the induction and maintenance of a pro-angiogenic profile, given the well-known role of hypoxia in promoting angiogenesis in all its forms. Here we present an overview of the literature focusing on the mechanisms implicated in the "angiogenic switch", which corresponds to the transition from the avascular to the vascular phase of the disease. We also review evidence on the anti-angiogenic effects of PI and IMiDs, which substantially contribute to their anti-MM activity. Finally, we summarize possible caveats and perspectives about antiangiogenic strategies that could be addressed to improve the efficacy of treatments for MM patients.

Bone marrow neovascularisation supports plasma cell tumour progression in patients with multiple myeloma (MM), and is partially sustained by bone marrow macrophages through their angiogenic and vasculogenic activities. As such, macrophages may be a target for antivascular treatment in MM. Here, we show that bortezomib (BZ) and zoledronic acid (ZOL) display distinct and synergistic inhibitory effects on cell proliferation, adhesion, migration and expression of angiogenic cytokines (i.e.: VEGF, bFGF, HGF and PDGF). Similar effects were found on capillarogenic organisation and expression of vascular markers in cells which became vasculogenic. VEGFR2 and ERK1/2 phosphoactivation as well as NF-kappaB activity were also inhibited. Overall these data provide evidence that the exposure of bone marrow macrophages in MM during the treatment with ZOL and BZ, alone and or in combination, impacts their angiogenic and vasculogenic properties, suggesting that these cells may be considered as a target of both drugs in MM patients., (Copyright 2009 Elsevier Ltd. All rights reserved.)

Fenretinide (4HPR), a nontoxic analog of ATRA, has been investigated in various malignancies but not in multiple myeloma (MM), a plasma cell malignancy associated with induction of osteolytic bone disease. Here we show that 4HPR induces apoptosis through increased level of ROS and activation of caspase-8, 9 and 3, and inhibits growth of several MM cell lines in a dose-dependent manner. Serum or co-culture with the supportive osteoclasts partially protects MM cells from 4HPR-induced growth inhibition. Sphingosine-1 phosphate (S1P) significantly protects MM cells from 4HPR-induced apoptosis suggesting that as in other malignancies, this drug up-regulates ceramide in MM cells. 4HPR has no toxic effects on non-malignant cells such as blood mononucleated cells, mesenchymal stem cells and osteoblasts, but markedly reduces viability of endothelial cells and mature osteoclasts and inhibits differentiation of osteoclasts and MM-induced tube formation. 4HPR is a potential anti-MM agent, affecting MM cells and MM-induced bone disease and angiogenesis., (2009 Elsevier Ireland Ltd.)

During the last decade, a central role for insulin-like growth factor 1 (IGF-1) in the pathophysiology of multiple myeloma (MM) has been well established. IGF-I provided by the tumor-microenvironment interaction may directly and indirectly facilitate the migration, survival and expansion of the MM cells in the bone marrow (BM). The inhibition of the IGF-1R-mediated signaling pathway has recently been suggested to be a possible new therapeutic principle in MM. Using the mouse 5T2MM model, we now demonstrate that targeting the IGF-1R using picropodophyllin (PPP) in a therapeutical setting not only has strong antitumor activity on the established MM tumor but also influences the BM microenvironment by inhibiting angiogenesis and bone disease, having a profound effect on the survival of the mice. At therapeutically achievable concentrations of PPP, the average survival was 180 days for the PPP-treated mice as compared to 100 days for vehicle-treated mice. PPP used as single drug treatment in the 5T2MM model resulted in a decrease of tumor burden by 65% while the paraprotein concentrations were reduced by 75%. This decrease was associated with a significant inhibition of tumor-associated angiogenesis and osteolysis. The present studies on the biological effects of PPP in the 5T2MM model constitute an important experimental platform for future therapeutic implementation., ((c) 2007 Wiley-Liss, Inc.)

Background: In multiple myeloma (MM), bone marrow angiogenesis parallels tumour progression and correlates with disease activity. Recent studies have proved resveratrol possesses antiangiogenic activity in vitro and in vivo. In this study, we examined the effects of resveratrol on myeloma cell dependent angiogenesis and the effects of resveratrol on some important angiogenic factors of RPMI 8226 cells., Methods: RPMI 8226 cells were cocultured with human umbilical vein endothelial cells (HUVECs) to evaluate the effects of myeloma cells on angiogenesis. The RPMI 8226 cells were treated with various concentrations of resveratrol (6.25 - 50.00 micromol/L) for different times (12 - 72 hours). Reverse transcriptase polymerase chain reaction (RT-PCR) was used to assay vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), metalloproteinases (MMP)-2 and MMP-9 mRNA. Gelatin zymography was used to analyze MMP-2 and MMP-9 activity. VEGF and bFGF proteins secreted by the cells in the medium were quantified by enzyme linked immunosorbent assay (ELISA)., Results: Cell proliferation, migration and differentiation of HUVECs markedly increased by coculture with RPMI 8226 cells. Resveratrol inhibited proliferation, migration and tube formation of HUVECs cocultured with myeloma cells in a dose dependent manner. Treatment of RPMI 8226 cells with resveratrol caused a decrease in MMP-2 and MMP-9 activity. Resveratrol inhibited VEGF and bFGF protein expression in a dose and time dependent manner. Furthermore, decreased levels of VEGF, bFGF, MMP-2 and MMP-9 mRNA from cells treated with various concentrations of resveratrol confirmed its antiangiogenic action at the level of gene expression., Conclusions: Resveratrol inhibits multiple myeloma angiogenesis by regulating expression and secretion of VEGF, bFGF, MMP-2 and MMP-9. Resveratrol may be a potential candidate for the treatment of multiple myeloma.

The aim of this study was to investigate the effect of [(-)-epigallocatechin-3-gallate (EGCG)] on angiogenesis induced by multiple myeloma cell line KM3 and its mechanism. The effects of KM3 cell supernatant after being treated with EGCG in different concentrations on migration and vascular formation ability of endothelial cell line HUVEC were investigated through culture of MM cell line KM3 in vitro. The secretion level of vascular endothelial growth factor (VEGF) in KM3 cell supernatant and the expression level of VEGF mRNA in KM3 were detected by ELISA and RT-PCR respectively. The results indicated that the KM3 cell supernatant significantly induced endothelial cell migration and vascular formation in vitro. EGCG inhibited the effect of endothelial cell migration induced by KM3 cell supernatant, and the numbers of migrated cells were 414 +/- 27, 299 +/- 70, 202 +/- 42 and 116 +/- 13 at 5, 25, 50, 100 micromol/L respectively. The numbers of migrated cells showed negative correlation with the dose of EGCG (r = -0.952, p < 0.05). The areas of the capillary-like structures decreased while the concentrations of EGCG increased, 88343.9 +/- 3231.1 microm(2) at 25 micromol/L, 60897.5 +/- 914.1 microm2 at 50 micromol/L, which were significantly less than that in the control (p < 0.01) and showed negative correlation with the dose of EGCG (r = -0.888, p < 0.05). 48 hours after treatment with EGCG at concentrations of 5, 25, 50 and 100 micromol/L, the levels of VEGF in the culture supernatant were 1399.0 +/- 47.4, 660.1 +/- 5.7, 108.5 +/- 5.8 and 26.2 +/- 18.6 pg/ml respectively. Except 5 micromol/L, all the other groups showed significant changes while compared with the controls (p < 0.01). Furthermore, EGCG depressed the mRNA expression of VEGF in KM3 cells in a dose-dependent manner. It is concluded that the EGCG can significantly inhibit angiogenic ability of multiple myeloma KM3 cells, its pharmacological mechanism may be downregulation of VEGF mRNA expression and reduction of VEGF secretion.

The vascularization is a very important part of a structure of each tissue both normal, including bone marrow stroma, and pathologically changed. Neoplastic tissues secure supplying in necessary substances for growth and expansion through regulated by its own cells neovasculation. Key role in multipotential cell's differentiation to endothelial cells plays regulatory system consisted of vascular-epithelial growth factor's family (VEGF B, C, D), receptors VEGFR-1, -2, -3, and system Tie2/angiopoetins. Stimulation and importance of angiogenesis for expansion of neoplastic diseases is a current problem in oncology. It is pointed to importance of neovascularization in pathogenesis of acute and chronic leukemias, lymphomas and multiple myeloma. The knowledge of the importance ofvascularization of neoplastic tissues is availing in therapy (researching of substances inhibiting angiogenesis--semaxinib, SU6668, ZD 6474, thalidomid, cetuximab, gefitinib, interferon-alpha, irradiation and others), in diagnostics as a monitoring of a success of the therapy, and in prognosis. Inhibitors ofangiogenesis are antineoplastic drugs with relatively lower toxicity, and lower risk of drug-resistance than conventional chemotherapy what has the importance especially during prolong administration, so they can be an alternative way of therapeutic process. During qualification for antiangiogenic therapy it is necessary to have a consciousness of its limited efficiency.

Purpose: A second-generation tetrathiomolybdate analogue (ATN-224; choline tetrathiomolybdate), which selectively binds copper with high affinity, is currently completing two phase I clinical trials in patients with advanced solid and advanced hematologic malignancies. However, there is very little information about the mechanism of action of ATN-224 at the molecular level., Experimental Design: The effects of ATN-224 on endothelial and tumor cell growth were evaluated in cell culture experiments in vitro. The antiangiogenic activity of ATN-224 was investigated using the Matrigel plug model of angiogenesis., Results: ATN-224 inhibits superoxide dismutase 1 (SOD1) in tumor and endothelial cells. The inhibition of SOD1 leads to inhibition of endothelial cell proliferation in vitro and attenuation of angiogenesis in vivo. The inhibition of SOD1 activity in endothelial cells is dose and time dependent and leads to an increase in the steady-state levels of superoxide anions, resulting in the inhibition of extracellular signal-regulated kinase phosphorylation without apparent induction of apoptosis. In contrast, the inhibition of SOD1 in tumor cells leads to the induction of apoptosis. The effects of ATN-224 on endothelial and tumor cells could be substantially reversed using Mn(III)tetrakis(4-benzoic acid)porphyrin chloride, a catalytic small-molecule SOD mimetic., Conclusions: These data provide a distinct molecular target for the activity of ATN-224 and provide validation for SOD1 as a target for the inhibition of angiogenesis and tumor growth.

Although autologous stem cell transplant is an effective therapy for patients with multiple myeloma and extends progression-free survival (PFS) and overall survival (OS), patients show a continued pattern of recurrent disease. Twenty-nine patients were enrolled in a phase II study investigating the tolerability and efficacy of maintenance thalidomide following single autologous peripheral blood stem cell transplant. Six to eight weeks after transplant, patients were started on maintenance thalidomide at 50 mg a day. The dose was gradually escalated to a target dose of 400 mg a day and continued until disease progression or 6 months after achieving complete remission (CR) for a maximum total duration of 18 months. At 6 months, 13 patients (45%) achieved CR or near complete remission (positive immunofixation without any evidence of disease). The estimated 2-year OS was 83% and PFS was 49%. Median tolerated dose of thalidomide was 200 mg a day. In conclusion, thalidomide as maintenance therapy is feasible and may improve outcome after single autologous stem cell transplant., (Bone Marrow Transplantation (2006) 37, 819-824. doi:10.1038/sj.bmt.1705349; published online 20 March 2006.)

In order to explore the probability of curcumin treating multiple myeloma (MM) via the inhibition of angiogenesis, the expressions of brain derived neurotrophic factor (BDNF) and its specific receptor in human MM cells and endothelial cells were detected by reverse transcriptase-polymerase chain reaction (RT-PCR). The angiogenic activity was evaluated by endothelial cell migration assay and tubule formation assay in vitro. The results showed that exogenous BDNF significantly induced endothelial cell tubule formation and endothelial cell migration, these two effects were inhibited by curcumin. Furthermore, BDNF was detected in the MM cell and TrkB was detected in the endothelial cell and curcumin depressed the mRNA expression of BDNF and TrkB in the dose- and time-dependent manners. It is concluded that BDNF is a novel angiogenesis protein. Curcumin interrupts the interaction between multiple myeloma cells and endothelial cells by reducing TrkB expression in endothelial cells and inhibiting BDNF production in multiple myeloma cells, eventually, resulting in inhibition of angiogenesis. This is probably one part of the mechanism of the curcumin treating MM via the inhibition of angiogenesis.

In order to explore the molecular mechanism of arsenic trioxide treating multiple myeloma (MM) via inhibition of angiogenesis, the expression of brain derived neurotrophic factor (BDNF) and its specific receptor TrkB in human MM cell line KM3 and endothelial cell line ECV304 was detected by Western blotting. The angiogenic activity was evaluated by wound migration assay and tubule formation assay in vitro. The results showed that BDNF was detected in the MM cells and TrkB in the endothelial cells. Furthermore, 100 ng/mL BDNF could significantly induced endothelial cell tubule formation and wound migration. As2 O3 depressed the expression of BDNF and TrkB in the dose- and time-dependent manner. As2 O3 inhibited BDNF-induced wound migration and capillary tube formation. It was concluded that BDNF is a novel angiogenic protein as well as VEGF and has a relation with the pathogenesis of MM. As2 O3 interrupts a paracrine loop between MM cells and endothelial cells by down-regulating the TrkB expression in endothelial cells and inhibiting BDNF production in MM cells, finally resulting in inhibition of MM angiogenesis. This is probably one part of the mechanisms of the As2 O3 treating MM via the inhibition of angiogenesis.

Purpose: Increased bone marrow angiogenesis and vascular endothelial growth factor (VEGF) levels are of adverse prognostic significance in patients with multiple myeloma (MM). VEGF, a soluble circulating angiogenic molecule, acts via receptor tyrosine kinases, including VEGF receptor 2. SU5416 is a small molecule VEGF receptor 2 inhibitor., Experimental Design: Adult patients with advanced MM were entered on a multicenter phase II study., Results: Twenty-seven patients (median age 69, range 39-79), median 4 (0-10) lines of prior therapy, 14 with prior thalidomide therapy, received SU5416 at 145 mg/m(2) twice weekly i.v. for a median of two 4-week cycles (range 0.2-9). Grade 3/4 toxicities were rarely observed; the most frequent was thrombocytopenia (12%). Mild-to-moderate toxicities included nausea (63%), headache (56%), diarrhea, vomiting (both 37%), and fatigue (33%). There were three thromboembolic episodes and five cases of new onset hypertension. Two (7%) patients did not complete the first 4-week cycle of therapy because of adverse events (pneumonia and headache). There were no objective responses. Four patients had disease stabilization for >/==" BORDER="0">4 months. A decrease in median VEGF plasma levels was observed in patients with stable disease (n = 7) compared with patients with progressive disease (n = 5). Overall median survival was 42 weeks (range 3-92+)., Conclusions: Although SU5416 had minimal clinical activity, signs of biological activity (decrease in plasma VEGF levels) suggest that angiogenic modulation may be of value in patients with MM.

Angiogenesis is defined as a neoformation of blood vessels of capillary origin. Hematopoiesis is closely linked with angiogenesis, for they share a common ancestor, the hemangioblast. Although it is well established that growth in solid tumors is dependent on angiogenesis, its role in hematologic malignancies has not yet been clarified. In this review, the direct evidence, ie, increased microvessel density, and the indirect evidence, ie, elevated level of angiogenic factors or overexpression of messenger RNA or protein of angiogenic factors, for and against the role of angiogenesis in the development and progression of hematologic malignancies are presented.

There is accumulating evidence that leukemias and other hematologic diseases are angiogenesis-dependent. Therefore, angiogenesis inhibitors may be useful adjuncts to conventional therapies in the treatment of these diseases. When all conventional therapy has failed, an angiogenesis inhibitor may be successfully used alone, as has been demonstrated in the treatment of multiple myeloma by thalidomide. The experimental and clinical evidence that the efficacy of thalidomide against multiple myeloma is mediated in part by its antiangiogenic activity is presented here. In current clinical trials throughout the United States, angiogenesis inhibitors are being used against cancer in combination with conventional chemotherapy or radiotherapy. Angiogenesis inhibitors are also being used in combination with each other. This practice may increase as different angiogenesis inhibitors become more widely available., (Copyright 2001 by W.B. Saunders Company.)