How to treat patients with relapsed/refractory multiple myeloma: evidence-based information and opinions

Introduction: Relapsed/refractory multiple myeloma (rrMM) remains a difficult condition to treat despite the availability of new drugs. This review aims to provide evidence to guide physicians in the choice of salvage therapy in certain subgroups of patients.

Areas covered: The review attempts to present evidence-based information and suggest possible approaches based on data on previous therapies, previous remission duration and toxicity of previous treatments, patient's co-morbidities and disease characteristics at relapse. Unfortunately, little evidence is available; there are no large and/or randomized trials, direct comparisons of drugs or combinations for rrMM patients to draw any definite conclusion.

Expert opinion: Almost all the studies presented here suggest that depth of response is a key factor also for patients with rrMM. Identifying the best approach between combinations and sequential therapies remains controversial. Several studies favor the former approach in early relapse as it leads to a higher complete response rate, regardless of previous therapies. However, in both strategies, achieving maximal response should always remain a main goal. Consolidation/maintenance therapy is beneficial both in combination and sequential therapies also in rrMM. Second generation new drugs, such as pomalidomide, carfilzomib, bendamustine and HDAC inhibitors, will probably expand the rescue possibilities also in this setting.     

Current therapeutic uses of lenalidomide in multiple myeloma

Thalidomide has demonstrated a broad spectrum of pharmacological and immunological effects, with potential therapeutic applications that span a wide spectrum of diseases: cancer and related conditions; infectious diseases; autoimmune diseases; dermatological diseases; and other disorders such as sarcoidosis, macular degeneration and diabetic retinopathy. Immunomodulatory derivative lenalidomide has more potent antitumour and anti-inflammatory effects. The molecular mechanisms of antitumour activity of lenalidomide have been extensively studied in multiple myeloma (MM). It directly induces growth arrest and/or apoptosis of even drug-resistant MM cells; inhibits binding of MM cells to bone marrow extracellular matrix proteins and stromal cells; modulates cytokine secretion and inhibits angiogenesis in the bone marrow milieu; and augments host antitumour immunity. Importantly, lenalidomide induces significant clinical responses even in patients with relapsed/refractory MM. Therefore, lenalidomide represents a new class of antitumour agents that is useful in the treatment of MM. Lenalidomide has received fast track designation from the FDA for the treatment of MM and myelodysplastic syndromes.     

New generation pharmacotherapy in elderly multiple myeloma patients

Background: Observational databases have demonstrated that the overall prognosis of multiple myeloma patients has markedly improved over the past decade, yet the greatest strides have been attained in younger rather than older patients. Objective: To review recent clinical trials that include new generation agents (thalidomide, lenalidomide and bortezomib) and autologous stem cell transplantation in older multiple myeloma patients. Results: Conventional regimens such as melphalan plus prednisone can be improved with the addition of thalidomide or bortezomib: more patients attain complete and near-complete remission, and progression-free survival rates are nearly doubled. In addition, autologous hematopoietic stem cell transplantation studies show that this treatment approach can be used successfully in selected older myeloma patients in whom the toxicity profile of autotransplant and resulting overall survival may be similar to that obtained in the younger patient group. Conclusions: In the advanced-age population, implementation of new therapies results in significant benefits in older as well as younger patients.     

Biotechnology and genetic engineering in the new drug development. Part II. Monoclonal antibodies,modern vaccines and gene therapy

Monoclonal antibodies, modern vaccines and gene therapy have become a major field in modern biotechnology, especially in the area of human health and fascinating developments achieved in the past decades are impressive examples of an interdisciplinary interplay between medicine, biology and engineering. Among the classical products from cells one can find viral vaccines, monoclonal antibodies, and interferons, as well as recombinant therapeutic proteins. Gene therapy opens up challenging new areas. In this review, a definitions of these processes are given and fields of application and products, as well as the future prospects, are discussed.     

三氧化二砷联合沙利度胺对骨髓增生异常综合征的调节作用

目的 探讨三氧化二砷联合沙利度胺对骨髓增生异常综合征(MDS)的调节作用.方法 将46例MDS患者随机分为2组,每组23例.治疗组给予三氧化二砷及沙利度胺,对照组仅给予三氧化二砷.治疗2个月后评估2组总体疗效,比较血红蛋白(Hb)、中性粒细胞绝对值(ANC)、血小板计数(PLT)、骨髓原始细胞比例及不良反应的差异.结果 治疗组总有效率显著高于对照组.治疗组Hb、ANC、PLT水平及骨髓原始细胞比例的改善程度均显著大于对照组.2组不良反应发生率无显著差异.结论 与单独应用三氧化二砷相比,三氧化二砷联合沙利度胺可显著改善MDS患者三系血细胞,降低骨髓原始细胞比例,提高近期疗效,且不增加不良反应.     

Slit2/Robo1信号在胃肠道血管畸形发病机制中的作用以及沙利度胺对其表达的影响

目的：探讨Slit2/Robo1信号在胃肠道血管畸形发病机制中的作用以及沙利度胺对其表达的影响。方法：收集7例胃肠道血管畸形患者血管病变组织与正常黏膜组织,分别检测Slit2,Robo1,VEGF基因和蛋白水平的表达。体外培养原代人脐静脉内皮细胞至对数生长期,同步化后用不同浓度的沙利度胺（50、100、200mg/L）作用24-48小时后,实时定量PCR法测定处理组与溶剂对照组的Slit2,Robo1,VEGF mRNA表达水平,免疫印迹方法测定Slit2,Robo1,VEGF蛋白表达水平。结果：显示胃肠道血管畸形患者血管病变组织中Slit2,Robo1,VEGF基因及蛋白表达水平显著高于正常黏膜组织。沙利度胺能够明显抑制Slit2,Robo1,VEGF基因与蛋白的表达。结论：Slit2,Robo1可能与胃肠道血管畸形的发病相关,而沙利度胺可抑制其表达,这一作用可能是沙利度胺抑制血管生成,从而治疗GIVM的机制之一。     

硼替佐米联合地塞米松与沙利度胺治疗多发性骨髓瘤的效果

目的比较硼替佐米＋地塞米松＋沙利度胺（BDT）方案与长春地辛＋表柔比星＋地塞米松＋沙利度胺（VADT）方案治疗多发性骨髓瘤（MM）的临床效果。方法MM病人67例,应用BDT方案治疗30例,VADT方案治疗37例,均治疗4个疗程,比较两组治疗前、治疗后β2-微球蛋白、免疫球蛋白、骨髓瘤细胞的变化,并比较两组疗效。结果BDT组及VADT组化疗后β2-微球蛋白、免疫球蛋白、骨髓瘤细胞均低于化疗前,差异有显著性（t=2．837～7．562,P％0．05）。BDT组完全缓解（CR）占13．0％,接近完全缓解（ncR）占20．0％,部分缓解（PR）占53．0％,微小反应（MR）占6．7％,总有效率93．3％;VADT组CR占3．0％,nCR占10．8％,PR占40．5％,MR占16．2％,总有效率70．3％,两组疗效比较,差异有显著性（Hc=51．67,P〈0．05）。结论BDT方案治疗MM效果优于VADT方案,且起效快,可改善病人的预后。     

Environmental impact on vascular development predicted by high-throughput screening

Background: Understanding health risks to embryonic development from exposure to environmental chemicals is a significant challenge given the diverse chemical landscape and paucity of data for most of these compounds. High-throughput screening (HTS) in the U.S. Environmental Protection Agency (EPA) ToxCast™ project provides vast data on an expanding chemical library currently consisting of > 1,000 unique compounds across > 500 in vitro assays in phase I (complete) and Phase II (under way). This public data set can be used to evaluate concentration-dependent effects on many diverse biological targets and build predictive models of prototypical toxicity pathways that can aid decision making for assessments of human developmental health and disease.Objective: We mined the ToxCast phase I data set to identify signatures for potential chemical disruption of blood vessel formation and remodeling.Methods: ToxCast phase I screened 309 chemicals using 467 HTS assays across nine assay technology platforms. The assays measured direct interactions between chemicals and molecular targets (receptors, enzymes), as well as downstream effects on reporter gene activity or cellular consequences. We ranked the chemicals according to individual vascular bioactivity score and visualized the ranking using ToxPi (Toxicological Priority Index) profiles.Results: Targets in inflammatory chemokine signaling, the vascular endothelial growth factor pathway, and the plasminogen-activating system were strongly perturbed by some chemicals, and we found positive correlations with developmental effects from the U.S. EPA ToxRefDB (Toxicological Reference Database) in vivo database containing prenatal rat and rabbit guideline studies. We observed distinctly different correlative patterns for chemicals with effects in rabbits versus rats, despite derivation of in vitro signatures based on human cells and cell-free biochemical targets, implying conservation but potentially differential contributions of developmental pathways among species. Follow-up analysis with antiangiogenic thalidomide analogs and additional in vitro vascular targets showed in vitro activity consistent with the most active environmental chemicals tested here.Conclusions: We predicted that blood vessel development is a target for environmental chemicals acting as putative vascular disruptor compounds (pVDCs) and identified potential species differences in sensitive vascular developmental pathways.     

Clinical impact of chromosomal aberrations in multiple myeloma

Chromosomal aberrations are frequently found in multiple myeloma cells and play a major role in patient outcome and management of the disease. The most important chromosomal aberrations associated with poor outcome are del(17p), t(4;14), t(14;16) and t(14;20). Others that may be associated with adverse prognosis include amp(1)(q21), del(1p32), del(13), del(8p21) and hypodiploidy. Many chromosomal aberrations have no or uncertain impact; for example, t(11;14), t(8;14) and hyperdiploidy. Attempts have been made to overcome the negative prognostic impact of chromosomal aberrations using autologous or allogeneic transplantation or new immunomodulatory drugs such as thalidomide, lenalidomide and the proteasome inhibitor bortezomib, but the results are controversial. Data suggest that allogeneic transplantation and treatment with bortezomib or lenalidomide may help to overcome the negative effect of del(13) on prognosis, whereas bortezomib may have some influence on reducing the impact of del(17p), t(4;14) and t(14;16). Chromosome analysis should always be performed at diagnosis of multiple myeloma to improve the prediction of outcome and to aid treatment decision-making.