Mechanism of action of lenalidomide in hematological malignancies

Prevention of chemotherapy-induced peripheral neuropathy: A review of recent findings

Chemotherapy-induced peripheral neuropathy (CIPN) is an adverse effect of chemotherapy that is frequently experienced by patients receiving treatment for cancer. CIPN is caused by many of the most commonly used chemotherapeutic agents, including taxanes, vinca alkaloids, and bortezomib. Pain and sensory abnormalities may persist for months, or even years after the cessation of chemotherapy. The management of CIPN is a significant challenge, as it is not possible to predict which patients will develop symptoms, the timing for the appearance of symptoms can develop anytime during the chemotherapy course, there are no early indications that warrant a reduction in the dosage to halt CIPN progression, and there are no drugs approved to prevent or alleviate CIPN. This review focuses on the etiology of CIPN and will highlight the various approaches developed for prevention and treatment. The goal is to guide studies to identify, test, and standardize approaches for managing CIPN.

Cyclosporine Broadens the Therapeutic Potential of Lenalidomide in Myeloid Malignancies

The immunomodulatory drug lenalidomide is used for the treatment of certain hematologic malignancies, including myelodysplastic syndromes (MDS). Lenalidomide interacts with cereblon (CRBN), a component of the CRL4CRBN E3 ubiquitin ligase complex, leading to ubiquitination and subsequent degradation of substrates, such as transcription factor Ikaros (Ikaros family zinc finger 1, IKZF1). With a genome loss of function screen, we recently identified two novel pathways mediated by lenalidomide in MDS. In this review, we summarized the major findings of these two pathways and their clinical implications. Depletion of G protein-coupled receptor 68 (GPR68) or an endogenous calcineurin (CaN) inhibitor, regulator of calcineurin 1 (RCAN1), reversed the inhibitory effect of lenalidomide on MDSL cells, an MDS cell line. Intriguingly, both GPR68 and RCAN1 expression levels were upregulated in MDSL cells after treatment with lenalidomide that was dependent on diminishment of IKZF1, indicating that IKZF1 functioned as a transcription repressor for GPR68 and RCAN1. Mechanistic studies revealed that upregulation or activation of GPR68 induced a Ca2+/calpain pro-apoptotic pathway, while upregulation of RCAN1 inhibited the CaN pro-survival pathway in MDSL cells. Notably, the pharmacological CaN inhibitor, cyclosporine, enhanced the sensitivity to lenalidomide in MDS as well as acute myeloid leukemia (AML). Surprisingly, pretreatment with lenalidomide reversed the immunosuppressive effects of cyclosporine on T lymphocytes. Our studies suggest that lenalidomide mediates degradation of IKZF1, leading to derepression of GPR68 and RCAN1 that activates the Ca2+/calpain pro- apoptotic pathway and inhibits the CaN pro-survival pathway, respectively. Our studies implicate that cyclosporine extends the therapeutic potential of lenalidomide to myeloid malignancies without compromising immune function.

A Tale of Two Immunodeficiencies: A Case of Multiple Myeloma Associated with Profound Immune Defect Mimicking Common Variable Immunodeficiency Syndrome

INTRODUCTION

Multiple myeloma (MM) is a clonal plasma cell disorder commonly associated with secondary immune deficiency. By contrast, common variable immunodeficiency (CVID) is a primary immunodeficiency characterized by low serum levels of immunoglobulins (IgG, IgA, and/or IgM) and inability to produce specific protective antibodies in response to infections and immunizations. Besides a defective immune system and susceptibility to infections, CVID is associated with autoimmune disorders, gastrointestinal tract inflammation, granulomatous disease, and malignancies. Although MM and CVID both manifest an abnormal immune system homeostasis, the pathogenesis of the immune defect is distinctly different: Quantitative deficiency of the normal plasma cells in the former and qualitative defect in plasma cell maturation in the latter.

CASE PRESENTATION

An unusual case of MM associated with profound immunodeficiency mimicking CVID occurred in a 51-year-old man with a history of numerous bacterial infections and low γ-globulin levels.

DISCUSSION

A hypothetical connection between MM and CVID is discussed. Patients with MM who have an unusually high burden of infections and profound immune deficit persisting even after successful myeloma therapy merit recognition as a distinct cohort that warrants heightened attention from clinicians and scientists.

A Novel Nanomicellar Combination of Fenretinide and Lenalidomide Shows Marked Antitumor Activity in a Neuroblastoma Xenograft Model

Purpose

Currently >50% of high-risk neuroblastoma (NB) patients, despite intensive therapy and initial partial or complete response, develop recurrent NB due to the persistence of minimal residual disease (MRD) that is resistant to conventional antitumor drugs. Indeed, their low therapeutic index prevents drug-dose escalation and protracted administration schedules, as would be required for MRD treatment. Thus, more effective and less toxic therapies are urgently needed for the management of MRD. To address this aim, we evaluated a new combination of fenretinide and lenalidomide, both endowed with antitumor activity and low-toxicity profiles. New nanomicelles were prepared as carriers for this combination to maximize bioavailability and accumulation at the tumor site because of the enhanced permeability and retention (EPR) effect.

Experimental design

New nanomicelles containing the fenretinide–lenalidomide combination (FLnMs) were prepared by a one-step method, providing high drug encapsulation and micelle dimensions suitable for tumor accumulation. Their administration to mice bearing human NB xenografts allowed us to evaluate their efficacy in comparison with the nanomicelles containing fenretinide alone (FnMs).

Results

Treatment by FLnMs significantly decreased the tumor growth of NB xenografts. FLnMs were more active than FnMs despite comparable fenretinide concentrations in tumors, and lenalidomide alone did not show cytotoxic activity in vitro against NB cells. The tumor mass at the end of treatment with FLnMs was predominantly necrotic, with a decreased Ki-67 proliferation index.

Conclusion

FLnMs provided superior antitumor efficacy in NB xenografts compared to FnMs. The enhanced efficacy of the combination was likely due to the antiangiogenic effect of lenalidomide added to the cytotoxic effect of fenretinide. This new nanomicellar combination is characterized by a low-toxicity profile and offers a novel therapeutic option for the treatment of high-risk tumors where the persistence of MRD requires repeated administrations of therapeutic agents over long periods of time to avoid recurrent disease.

Pain Management in Patients with Multiple Myeloma: An Update

Most patients with multiple myeloma (MM) suffer from chronic pain at every stage of the natural disease process. This review focuses on the most common causes of chronic pain in MM patients: (1) pain from myeloma bone disease (MBD); (2) chemotherapy-induced peripheral neuropathy as a possible consequence of proteasome inhibitor therapy (i.e., bortezomib-induced); (3) post-herpetic neuralgia as a possible complication of varicella zoster virus reactivation because of post-transplantation immunodepression; and (4) pain in cancer survivors, with increasing numbers due to the success of antiblastic treatments, which have significantly improved overall survival and quality of life. In this review, non-pain specialists will find an overview including a detailed description of physiopathological mechanisms underlying central sensitization and pain chronification in bone pain, the rationale for the correct use of analgesics and invasive techniques in different pain syndromes, and the most recent recommendations published on these topics. The ultimate target of this review was to underlie that different types of pain can be observed in MM patients, and highlight that only after an accurate pain assessment, clinical examination, and pain classification, can pain be safely and effectively addressed by selecting the right analgesic option for the right patient.

B-cell acute lymphoblastic leukemia in an elderly man with plasma cell myeloma and long-term exposure to thalidomide and lenalidomide: a case report and literature review

BACKGROUND

The advent of the immunomodulatory imide drugs (IMiDs) lenalidomide and thalidomide for the treatment of patients with plasma cell myeloma (PCM), has contributed to more than a doubling of the overall survival of these individuals. As a result, PCM patients join survivors of other malignancies such as breast and prostate cancer with a relatively new clinical problem - second primary malignancies (SPMs) - many of which are a result of the treatment of the initial cancer. PCM patients have a statistically significant increased risk for acute myeloid leukemia (AML) and Kaposi sarcoma. IMiD treatment has also been associated with an increased risk of myelodysplastic syndrome (MDS), AML, and squamous cell carcinoma of the skin. However, within these overlapping groups, acute lymphoblastic leukemia (ALL) is much less common.

CASE PRESENTATION

Herein, we describe an elderly man with PCM and a 14-year cumulative history of IMiD therapy who developed persistent pancytopenia and was diagnosed with B-cell acute lymphoblastic leukemia (B-ALL). He joins a group of 17 other patients documented in the literature who have followed a similar sequence of events starting with worsening cytopenias while on IMiD maintenance for PCM. These PCM patients were diagnosed with B-ALL after a median time of 36 months after starting IMiD therapy and at a median age of 61.5 years old.

CONCLUSIONS

PCM patients with subsequent B-ALL have a poorer prognosis than their de novo B-ALL counterparts, however, the very low prevalence rate of subsequent B-ALL and high efficacy of IMiD maintenance therapy in PCM should not alter physicians' current practice. Instead, there should be a low threshold for bone marrow biopsy for unexplained cytopenias.

Case of Stroke from Cerebral Vasculitis following Carfilzomib, Lenalidomide, and Dexamethasone Therapy in a Patient with Relapsing Multiple Myeloma

Lenalidomide, a synthetic derivation of thalidomide, in recent years, has been the backbone of multiple myeloma treatment leading to improved survival. Common adverse effects from lenalidomide-based regimens include hypertension, heart disease, and venous thromboembolism. Hence, thromboprophylaxis is recommended to reduce the risk of stroke. We report a case of stroke from cerebral vasculitis in a patient receiving carfilzomib, lenalidomide, and dexamethasone for relapsing multiple myeloma, not previously published. Medical oncologists should be aware of other causes of stroke among multiple myeloma patients receiving a lenalidomide-based regimen to prevent its occurrence.

Lenalidomide Plus Hypomethylating Agent as a Treatment Option in Acute Myeloid Leukemia With Recurrent Genetic Abnormalities-AML With inv(3)(q21.3q26.2) or t(3;3)(q21.3;q26.2); GATA2, MECOM

INTRODUCTION

Acute myeloid leukemia (AML) is a heterogeneous clonal hematopoietic neoplasm. The cytogenetic changes associated with AML affect the response rate and survival and are one of the most important independent prognostic factors. AML with inv(3)(q21.3q26.2) or t(3;3)(q21.3;q26.2); GATA2, MECOM accounts for 1% to 2% of all forms of AML and has been associated with a younger age at diagnosis, a poor response to standard induction chemotherapy, and very poor long-term prognosis.

PATIENTS AND METHODS

We performed a single-center, retrospective cohort study comparing the outcomes with hypomethylating agent (HMA) plus lenalidomide to those with standard intensive induction therapies for newly diagnosed and relapsed/refractory AML with inv(3).

RESULTS

Of the 15 patients, 4 (26.7%) had received lenalidomide and HMA as primary therapy. The overall response rate (ORR) was 100% for the 4 patients who had received lenalidomide with HMA as first-line induction therapy. The ORR was 27.3% (3 of 11) for the patients who had received other induction regimens (P = .0256). The duration of response for first induction therapy was an average of 7.4 months after lenalidomide plus an HMA and a mean of 1.5 months after induction with other chemotherapy regimen (P = .057). The ORR for induction and reinduction therapy was also assessed, with an ORR of 21.4% (6 of 28) for alternative chemotherapy regimens and an ORR of 75% (6 of 8) for induction and reinduction with lenalidomide plus HMA (P = .0046).

CONCLUSIONS

The high ORR and reasonable duration of response could allow for potentially curative allogeneic hematopoietic cell transplantation for these patients with high-risk AML. Our initial data suggest that lenalidomide plus HMA is a promising approach for patients with AML with inv(3).

Maintenance therapy in AML: The past, the present and the future

Curative treatment in acute myeloid leukemia (AML) depends on successful induction therapy to achieve a complete remission (CR), and subsequent post-remission therapy to prevent relapse. High relapse rates after consolidation therapy and after allogeneic stem cell transplant contribute to suboptimal outcomes in AML patients, and continue to represent a difficult challenge. Effective maintenance therapy could play an important role in prolonging the remission interval in the post-consolidation setting, especially in high risk AML patients. Maintenance treatment approaches based on conventional chemotherapy, immunotherapy, hypomethylating agents, and targeted small molecules have been explored in this setting, but no data so far have been convincing enough to establish this approach as the standard of care. However, ongoing and future studies including novel targeted therapies may demonstrate promising efficacy that could facilitate incorporation of maintenance therapy into clinical practice. In this review we summarize previous and ongoing approaches of maintenance therapy in AML and discuss the most promising strategies.

Are We Ready to Treat Diffuse Large B-cell and High-Grade Lymphoma According to Major Genetic Subtypes?

Diffuse Large B-Cell Lymphoma (DLBCL) is a clinically and biologically heterogeneous disease. The revised Classification of Lymphoproliferative diseases published in 2016 (WHO, 2016) refined the previous DLBLC subtypes and identified four categories: DLBCL not otherwise specified (NOS), other lymphomas of large B cells, high grade B-cell lymphoma, and B-cell lymphoma unclassifiable. High grade B-cell lymphomas include the entities carrying MYC, BCL2 and/or BCL6 translocations or cases with blastoid morphology without DH translocations. This classification also acknowledges the cell of origin (COO) classification, that has only a limited impact on the choice of frontline treatment for DLBCL, as most patients still receive R-CHOP chemoimmunotherapy. Attempts to improve the outcomes of specific subgroups, especially COO groups, have so far had limited success. Newer analyses have further subdivided DLBCL into genomically distinct subsets, not yet incorporated in the WHO classification, which may facilitate targeted approaches to therapy. In this review, we discuss the subgroups that are recognized by the WHO 2016 classification, review the newer genomic data, and speculate on how this could alter the treatment landscape of DLBCL in the future. We also discuss novel approaches to salvage therapy in the broad context of the heterogeneity of DLBCL.

Outcome of paraosseous extra-medullary disease in newly diagnosed multiple myeloma patients treated with new drugs

Extramedullary disease is relatively frequent in multiple myeloma, but our knowledge on the subject is limited and mainly relies on small case series or single center experiences. Little is known regarding the role of new drugs in this setting. We performed a meta-analysis of eight trials focused on the description of extramedullary disease characteristics, clinical outcome, and response to new drugs. A total of 2,332 newly diagnosed myeloma patients have been included; 267 (11.4%) had extramedullary disease, defined as paraosseous in 243 (10.4%), extramedullary plasmocytoma in 12 (0.5%), and not classified in 12 (0.5%) patients. Median progression-free survival was 25.3 months and 25.2 in extramedullary disease and non-extramedullary disease patients, respectively. In multivariate analysis the presence of extramedullary disease did not impact on progression-free survival (hazard ratio 1.15, P=0.06), while other known prognostic factors retained their significance. Patients treated with immunomodulatory drugs, mainly lenalidomide, or proteasome inhibitors had similar progression-free survival and progression-free survival-2 regardless of extramedullary disease presence. Median overall survival was 63.5 months and 79.9 months (P=0.01) in extramedullary and non-extramedullary disease patients, respectively, and in multivariate analysis the presence of extramedullary disease was associated with a reduced overall survival (hazard ratio 1.41, P<0.001), in line with other prognostic factors. With the limits of the use of low sensitivity imaging techniques, that lead to an underestimation of extramedullary disease, we conclude that in patients treated with new drugs the detrimental effect of extramedullary disease at diagnosis is limited, that lenalidomide is effective as are proteasome inhibitors, and that these patients tend to acquire a more aggressive disease in later stages. (EUDRACT2005-004714-32, NCT01063179 NCT00551928, NCT01091831, NCT01093196, NCT01190787, NCT01346787, NCT01857115).

Cancer drug development: The missing links

IMPACT STATEMENT

The success rate for cancer drugs which enter into phase 1 clinical trials is utterly less. Why the vast majority of drugs fail is not understood but suggests that pre-clinical studies are not adequate for human diseases. In 1975, as per the Tufts Center for the Study of Drug Development, pharmaceutical industries expended 100 million dollars for research and development of the average FDA approved drug. By 2005, this figure had more than quadrupled, to $1.3 billion. In order to recover their high and risky investment cost, pharmaceutical companies charge more for their products. However, there exists no correlation between drug development cost and actual sale of the drug. This high drug development cost could be due to the reason that all patients might not respond to the drug. Hence, a given drug has to be tested in large number of patients to show drug benefits and obtain significant results.

Current advances in Hodgkin's lymphoma

Hodgkin's lymphoma is a highly treatable malignancy. It has high cure rates yet there are many patients who relapse or are refractory to treatment. Traditionally, treatment has been with conventional chemotherapy; however, the development of brentuximab vedotin and immune checkpoint inhibitors has revolutionized the care of Hodgkin's lymphoma. This is a review of the current advances in the management of Hodgkin's lymphoma and a review of ongoing clinical trials in the field.

Venous thromboembolism in patients with B-cell non-Hodgkin lymphoma treated with lenalidomide: a systematic review and meta-analysis

Lenalidomide is associated with increased risk of thromboembolism (VTE) in patients with multiple myeloma. This risk has not previously been defined in B-cell non-Hodgkin lymphoma (NHL), for which lenalidomide is also an active agent. We conducted a systematic literature search in Ovid MEDLINE (1946 to February 2017), Ovid EMBASE (1974 to February 2017), The Cochrane Library (Wiley), and Web of Science Core Collection for prospective studies evaluating lenalidomide-containing regimens in B-cell NHL with adequate reporting of patient characteristics, total cycles received, and safety data including VTE rates. The primary outcome was VTE events per 100 patient-cycles by meta-analysis using random-effects models. Our literature search identified 1719 citations; 28 articles were included. For all patients with B-cell NHL receiving lenalidomide, the rate of VTE per 100 patient-cycles was 0.77 (95% confidence interval [CI], 0.48-1.12; I², 67%). The rate for single-agent lenalidomide was 1.09 events per 100 patient-cycles (95% CI, 0.49-1.94; I², 76%), the rate for lenalidomide plus biologics was 0.49 (95% CI, 0.17-0.97; I², 59%), and the rate for lenalidomide plus chemotherapy was 0.89 (95% CI, 0.39-1.60; I², 57%). Rate of VTE events in B-cell NHL patients treated with lenalidomide in clinical trials is similar to the rate in multiple myeloma. The VTE rate appears to be lowest for lenalidomide combined with a biologic compared with single-agent lenalidomide or its combination with chemotherapy. This protocol was registered at www.crd.york.ac.uk/prospero/ as #CRD42017056042.

Cytomegalovirus Retinitis Associated with Lenalidomide Use for Multiple Myeloma in an Immunocompetent Patient

Purpose

The aim of this report is to present a case of cytomegalovirus (CMV) retinitis in an immunocompetent patient using lenalidomide.

Methods

Case report with fundus photography, spectral-domain optical coherence tomography, and fluorescein angiography imaging.

Results

A 55-year-old male with history of multiple myeloma treated with lenalidomide presented with blurriness and floaters in his right eye and was found to have vitreous biopsy-confirmed CMV retinitis. The patient was treated with pars plana vitrectomy, oral valganciclovir, and intravitreal foscarnet. More than one year later, the patient was doing well with visual acuity of 20/25 and no recurrence of retinitis.

Conclusion

This represents the second report of CMV retinitis associated with lenalidomide therapy. It suggests that even immunocompetent patients can be affected by CMV retinitis in the context of lenalidomide treatment. It is critical that patients being treated with lenalidomide receive prompt evaluation if they develop ophthalmic symptoms.

Response of high-risk MDS to azacitidine and lenalidomide is impacted by baseline and acquired mutations in a cluster of three inositide-specific genes

Specific myeloid-related and inositide-specific gene mutations can be linked to myelodysplastic syndromes (MDS) pathogenesis and therapy. Here, 44 higher-risk MDS patients were treated with azacitidine and lenalidomide and mutations analyses were performed at baseline and during the therapy. Results were then correlated to clinical outcome, overall survival (OS), leukemia-free-survival (LFS) and response to therapy. Collectively, 34/44 patients were considered evaluable for response, with an overall response rate of 76.25% (26/34 cases): 17 patients showed a durable response, 9 patients early lost response and 8 patients never responded. The most frequently mutated genes were ASXL1, TET2, RUNX1, and SRSF2. All patients early losing response, as well as cases never responding, acquired the same 3 point mutations during therapy, affecting respectively PIK3CD (D133E), AKT3 (D280G), and PLCG2 (Q548R) genes, that regulate cell proliferation and differentiation. Moreover, Kaplan–Meier analyses revealed that this mutated cluster was significantly associated with a shorter OS, LFS, and duration of response. All in all, a common mutated cluster affecting 3 inositide-specific genes is significantly associated with loss of response to azacitidine and lenalidomide therapy in higher risk MDS. Further studies are warranted to confirm these data and to further analyze the functional role of this 3-gene cluster.

Lenalidomide for the treatment of mantle cell lymphoma

INTRODUCTION

Although a variety of therapeutic schemes for Mantle Cell Lymphoma (MCL) have been attempted, the clinical outcome of patients continues to be unsatisfactory especially among patients with a very high-risk profile and in the relapsed/refractory setting. For this reason, recent clinical trials have explored novel approaches, either by the use of biological agents in chemotherapy-free schedules or by integrating them with chemoimmunotherapy regimens. Areas covered: The efficacy of lenalidomide monotherapy and combination therapy established in clinical studies mainly involving relapsed/refractory MCL is reviewed. The mechanism of action of lenalidomide is also discussed. Furthermore, the current position of lenalidomide in the MCL treatment algorithm is debated. Expert opinion: Lenalidomide demonstrated high efficacy and tolerability in several clinical trials as well as in retrospective real-world reports, even in patients who relapsed or were resistant to bortezomib and ibrutinib. In 2013, lenalidomide was approved by the Food and Drug Administration (FDA) for relapsed/refractory MCL after two prior therapies including at least one prior treatment with bortezomib. However, the potential synergistic anti-neoplastic effects of lenalidomide in combination with other biological agents, i.e. ibrutinib and venetoclax, especially in the management of p53-mutated cases, still remain an open issue.

Treatment of Lymphoid and Myeloid Malignancies by Immunomodulatory Drugs

Thalidomide and its derivatives (lenalidomide, pomalidomide, avadomide, iberdomide hydrochoride, CC-885 and CC-90009) form the family of immunomodulatory drugs (IMiDs). Lenalidomide (CC5013, Revlimid®) was approved by the US FDA and the EMA for the treatment of multiple myeloma (MM) patients, low or intermediate-1 risk transfusion-dependent myelodysplastic syndrome (MDS) with chromosome 5q deletion [del(5q)] and relapsed and/or refractory mantle cell lymphoma following bortezomib. Lenalidomide has also been studied in clinical trials and has shown promising activity in chronic lymphocytic leukemia (CLL) and non-Hodgkin lymphoma (NHL). Lenalidomide has anti-inflammatory effects and inhibits angiogenesis. Pomalidomide (CC4047, Imnovid® [EU], Pomalyst® [USA]) was approved for advanced MM insensitive to bortezomib and lenalidomide. Other IMiDs are in phases 1 and 2 of clinical trials. Cereblon (CRBN) seems to have an important role in IMiDs action in both lymphoid and myeloid hematological malignancies. Cereblon acts as the substrate receptor of a cullin-4 really interesting new gene (RING) E3 ubiquitin ligase CRL4CRBN. This E3 ubiquitin ligase in the absence of lenalidomide ubiquitinates CRBN itself and the other components of CRL4CRBN complex. Presence of lenalidomide changes specificity of CRL4CRBN which ubiquitinates two transcription factors, IKZF1 (Ikaros) and IKZF3 (Aiolos), and casein kinase 1α (CK1α) and marks them for degradation in proteasomes. Both these transcription factors (IKZF1 and IKZF3) stimulate proliferation of MM cells and inhibit T cells. Low CRBN level was connected with insensitivity of MM cells to lenalidomide. Lenalidomide decreases expression of protein argonaute-2, which binds to cereblon. Argonaute-2 seems to be an important drug target against IMiDs resistance in MM cells. Lenalidomide decreases also basigin and monocarboxylate transporter 1 in MM cells. MM cells with low expression of Ikaros, Aiolos and basigin are more sensitive to lenalidomide treatment. The CK1α gene (CSNK1A1) is located on 5q32 in commonly deleted region (CDR) in del(5q) MDS. Inhibition of CK1α sensitizes del(5q) MDS cells to lenalidomide. CK1α mediates also survival of malignant plasma cells in MM. Though, inhibition of CK1α is a potential novel therapy not only in del(5q) MDS but also in MM. High level of full length CRBN mRNA in mononuclear cells of bone marrow and of peripheral blood seems to be necessary for successful therapy of del(5q) MDS with lenalidomide. While transfusion independence (TI) after lenalidomide treatment is more than 60% in MDS patients with del(5q), only 25% TI and substantially shorter duration of response with occurrence of neutropenia and thrombocytopenia were achieved in lower risk MDS patients with normal karyotype treated with lenalidomide. Shortage of the biomarkers for lenalidomide response in these MDS patients is the main problem up to now.

Relief of intractable pruritus with romidepsin in patients with cutaneous T-cell lymphoma: A series of four cases

Cutaneous T-cell lymphomas (CTCL) are a relatively rare and heterogeneous group of non-Hodgkin lymphomas that typically present in the skin. The majority of patients with CTCL experience pruritus, which can interfere with daily activities, significantly impact quality of life, and is typically uncontrolled by standard anti-itch therapies. Several lymphoma treatments have reported anti-pruritic effects including romidepsin, a potent class 1 selective histone deacetylase inhibitor approved for the treatment of patients with CTCL who have had at least one prior systemic therapy. Here, we describe the cases of four patients with debilitating and refractory pruritus that were resolved with romidepsin. Resolution of pruritus was observed in both clinical responders and nonresponders, and dose modification was used successfully to manage adverse events and for maintenance treatment. The potential for pruritus relief with romidepsin should be considered when treating patients with CTCL.

Azacitidine with or without lenalidomide in higher risk myelodysplastic syndrome & low blast acute myeloid leukemia

Standard treatment for higher risk myelodysplastic syndromes, chronic myelomonocytic leukemia and low blast acute myeloid leukemia is azacitidine. In single arm studies, adding lenalidomide had been suggested to improve outcomes. The ALLG MDS4 phase II trial randomized such patients to standard azacitidine or combination azacitidine (75mg/m²/d days 1 to 5) with lenalidomide (10mg days 1–21 of 28-day cycle from cycle 3) to assess clinical benefit (alive without progressive disease) at 12 months. A total of 160 patients were enrolled; median age 70.7 years (range 42.5-87.2), 31.3% female with 14% chronic myelomonocytic leukemia, 12% acute myeloid leukemia and 74% myelodysplastic syndromes. Adverse events were similar in both arms. There was excellent delivery of protocol therapy (median azacitidine cycles 11 both arms) with few dose reductions, delays or early cessations. At median follow up 33.1 months (range 0.7-59.5), the rate of clinical benefit at 12 months was 65% azacitidine arm and 54% lenalidomide+azacitidine arm (P=0.2). There was no difference in clinical benefit between each arm according to WHO diagnostic subgroup or IPSS-R. Overall response rate was 57% in azacitidine arm and 69% in lenalidomide+azacitidine (P=0.14). There was no difference in progression- free or overall survival between the arms (each P>0.12). Although the combination of lenalidomide and azacitidine was tolerable, there was no improvement in clinical benefit, response rates or overall survival in higher risk myelodysplastic syndrome, chronic myelomonocytic leukemia or low blast acute myeloid leukemia patients compared to treatment with azacitidine alone. This trial was registered at www.anzc-tr.org.au as ACTRN12610000271000.

Ig-Like Transcript 2 (ILT2) Blockade and Lenalidomide Restore NK Cell Function in Chronic Lymphocytic Leukemia

One of the cardinal features of chronic lymphocytic leukemia (CLL) is its association with a profound immunosuppression. NK cell function is markedly impaired in CLL patients, who show a significant dysregulation of the expression of activating and inhibitory receptors. Here, we analyzed the role of the novel inhibitory receptor Ig-like transcript 2 (ILT2, also termed LIR-1, LILRB1) in the regulation of NK cells in CLL. Our results show that ILT2 expression was significantly decreased on leukemic cells and increased on NK cells of CLL patients, particularly in those with advanced disease and with bad prognostic features, such as those carrying chromosome del(11q). The immunomodulatory drug lenalidomide may regulate the expression of ILT2 and its ligands in CLL since it significantly increased the expression of ILT2 and partially reestablished the expression of its ligands on leukemic cells. Furthermore, lenalidomide significantly increased the activation and proliferation of NK cells, which was strongly enhanced by ILT2 blockade. Combining ILT2 blockade and lenalidomide activated NK cell cytotoxicity resulting in increased elimination of leukemic cells from CLL patients. Overall, we describe herein the role of an inhibitory receptor involved in the suppression of NK cell activity in CLL, which is restored by ILT2 blockade in combination with lenalidomide, suggesting that it may be an interesting therapeutic strategy to be explored in this disease.

Where does PD-1 blockade fit in HL therapy?

Genetic alterations of the PD-L1/PD-L2 locus on chromosome 9p24.1 are a defining biological feature of classical Hodgkin lymphoma (HL). The resulting programmed death-ligand 1 (PD-L1) expression on Hodgkin Reed-Sternberg cells as well as the PD-L1 expressed in the HL microenvironment result in an ineffective host antitumor immune response and make HL a ripe target for programmed cell death-1 (PD-1) blockade. Anti-PD-1 antibody monotherapy has been effective and well tolerated in patients with relapsed or refractory (rel/ref) HL, with the majority of patients experiencing an objective response (approximately two-thirds of patients) and a median duration of response of 16.6 months in the study with the longest follow-up. Based on these data, nivolumab and pembrolizumab were approved by the US Food and Drug Administration (FDA) for the treatment of advanced rel/ref HL. Evidence has emerged that patients with HL benefit from continued PD-1 blockade beyond disease progression according to traditionally defined response criteria, and that the addition of, or switch to, chemotherapy after anti-PD-1 antibody failure can potentially re-induce clinical response. Subsequent studies have evaluated novel anti-PD-1-based combination regimens as well as the use of anti-PD-1 antibody therapy earlier in the course of a HL patient's therapy, including first salvage therapy for rel/ref disease (eg, nivolumab plus brentuximab vedotin) and even first-line treatment (eg, nivolumab added to doxorubicin, vinblastine, dacarbazine chemotherapy). The current role of PD-1 blockade in HL is as monotherapy in patients with advanced rel/ref disease, but the results of ongoing studies and the evolving treatment landscape in HL will determine the role of PD-1 blockade in the future.

Crbn I391V is sufficient to confer in vivo sensitivity to thalidomide and its derivatives in mice

Thalidomide and its derivatives, lenalidomide and pomalidomide, are clinically effective treatments for multiple myeloma and myelodysplastic syndrome with del(5q). These molecules lack activity in murine models, limiting investigation of their therapeutic activity or toxicity in vivo. Here, we report the development of a mouse model that is sensitive to thalidomide derivatives because of a single amino acid change in the direct target of thalidomide derivatives, cereblon (Crbn). In human cells, thalidomide and its analogs bind CRBN and recruit protein targets to the CRL4CRBN E3 ubiquitin ligase, resulting in their ubiquitination and subsequent degradation by the proteasome. We show that mice with a single I391V amino acid change in Crbn exhibit thalidomide-induced degradation of drug targets previously identified in human cells, including Ikaros (Ikzf1), Aiolos (Ikzf3), Zfp91, and casein kinase 1a1 (Ck1α), both in vitro and in vivo. We use the Crbn I391V model to demonstrate that the in vivo therapeutic activity of lenalidomide in del(5q) myelodysplastic syndrome can be explained by heterozygous expression of Ck1α in del(5q) cells. We found that lenalidomide acts on hematopoietic stem cells with heterozygous expression of Ck1α and inactivation of Trp53 causes lenalidomide resistance. We further demonstrate that Crbn I391V is sufficient to confer thalidomide-induced fetal loss in mice, capturing a major toxicity of this class of drugs. Further study of the Crbn I391V model will provide valuable insights into the in vivo efficacy and toxicity of this class of drugs.

Evaluating Angiogenic Potential of Small Molecules Using Genetic Network Approaches

Control of microvascular network growth is critical to treatment of ischemic tissue diseases and enhancing regenerative capacity of tissue engineering implants. Conventional therapeutic strategies for inducing angiogenesis aim to deliver one or more proangiogenic cytokines or to over-express known pro-angiogenic genes, but seldom address potential compensatory or cooperative effects between signals and the overarching signaling pathways that determine successful outcomes. An emerging grand challenge is harnessing the expanding knowledge base of angiogenic signaling pathways toward development of successful new therapies. We previously performed drug optimization studies by various substitutions of a 2-(2,6-dioxo-3-piperidyl)isoindole-1,3-dione scaffold to discover novel bioactive small molecules capable of inducing growth of microvascular networks, the most potent of which we termed phthalimide neovascularization factor 1 (PNF1, formerly known as SC-3–149). We then showed that PNF-1 regulates the transcription of signaling molecules that are associated with vascular initiation and maturation in a time-dependent manner through a novel pathway compendium analysis in which transcriptional regulatory networks of PNF-1-stimulated microvascular endothelial cells are overlaid with literature-derived angiogenic pathways. In this study, we generated three analogues (SC-3–143, SC-3–263, SC-3–13) through systematic transformations to PNF1 to evaluate the effects of electronic, steric, chiral, and hydrogen bonding changes on angiogenic signaling. We then expanded our compendium analysis toward these new compounds. Variables obtained from the compendium analysis were then used to construct a PLSR model to predict endothelial cell proliferation. Our combined approach suggests mechanisms of action involving suppression of VEGF pathways through TGF-β andNR3C1 network activation.

Previously, we discovered a novel small molecule (PNF1) that is capable of inducing growth of microvascular networks, a mechanism that is very important in many regenerative applications. In this study, we alter the structure of PNF1 slightly to get three different analogues and focus on gaining insight into how these drugs induce their pro-angiogenic effects. This is done through a few techniques that result in a map of all the transcripts that are up- or downregulated as a result of administering the drug, a knowledge that is necessary for successful therapeutic strategies.

Angiogenesis and neovascularization is important in a number of regenerative medicine therapeutics, including soft tissue regeneration. Having a deep understanding of the transcriptional mechanism of small molecules with this angiogenic potential will aid in designing specific immunomodulatory biomaterials. In the future, we will study these drugs and their angiogenic properties in impactful and clinically translatable applications.

Severe Renal Allograft Rejection Resulting from Lenalidomide Therapy for Multiple Myeloma: Case Report

Lenalidomide, a thalidomide analogue, is an immunomodulatory drug currently used as a chemotherapeutic agent in treating certain hematologic malignancies, including multiple myeloma. The antineoplastic effect of lenalidomide may be due to its ability to modulate different components of the immune system as well as its antiangiogenic, antiproliferative, and direct cytotoxic activity. Given its immunomodulatory effects, lenalidomide may potentially elicit unintended immune activity against allografts in solid organ transplant recipients. Here, we present a case of a renal transplant recipient who developed multiple myeloma after transplantation and was treated with the use of lenalidomide, which precipitated severe acute T-cell-mediated rejection. Lenalidomide was thought to be causative, and after cessation of the drug her renal function stabilized.

Chronic immune response dysregulation in MDS pathogenesis

Chronic innate immune signaling in hematopoietic cells is widely described in myelodysplastic syndromes (MDS), and innate immune pathway activation, predominantly via pattern recognition receptors, increases the risk of developing MDS. An inflammatory component to MDS has been reported for many years, but only recently has evidence supported a more direct role of chronic innate immune signaling and associated inflammatory pathways in the pathogenesis of MDS. Here we review recent findings and discuss relevant questions related to chronic immune response dysregulation in MDS.

Cereblon gene expression and correlation with clinical outcomes in patients with relapsed/refractory multiple myeloma treated with pomalidomide: an analysis of STRATUS

We analyzed gene expression levels of CRBN, cMYC, IRF4, BLIMP1, and XBP1 in 224 patients with multiple myeloma treated with pomalidomide and low-dose dexamethasone in the STRATUS study (ClinicalTrials.gov: NCT01712789; EudraCT number: 2012-001888-78). Clinical responses were observed at all CRBN expression levels. A trend in progression-free survival (PFS; p = .038) and a potential trend in overall survival (OS; p = .059) favoring high CRBN expressers were observed; however, no notable difference in overall response rate (ORR) was observed. ORR (30%), median PFS (17.7 weeks), and median OS (52.3 weeks) in low-CRBN expressers were comparable to those in the STRATUS intent-to-treat population (ORR, 33%; median PFS, 20.0 weeks; median OS, 51.7 weeks). A trend in ORR (p = .050) favoring higher cMYC expressers was observed with no notable difference in PFS or OS. This analysis does not support exploring CRBN as a biomarker for selecting patients for pomalidomide therapy.

Lymphomas and thyroid: Bridging the gap

The thyroid gland is often involved in the development of neoplastic diseases, including lymphoproliferative disorders. The aim of this paper is to provide a comprehensive overview of the multiple interactions between lymphoma and thyroid. Through an extensive research among the literature, the relationship between lymphomas and thyroid can be established at various levels, and the possible interconnections are here summarized in 5 points: (1) the greater risk of lymphoma development in some thyroid diseases; (2) the primary thyroid lymphoma, with focus on issues related to the diagnosis, differential diagnosis, and treatment; (3) the incidence of thyroid involvement in primitive nodal lymphomas or in extranodal lymphomas of the other sites; (4) thyroid changes after treatment of lymphoma, in relation to the effects of radiation therapy and immuno-chemotherapy; (5) the incidental findings of thyroid changes, on imaging, in patients with lymphoma, without a direct involvement of the gland in malignant disease. In conclusion, issues that until now have been dealt with separately will therefore be analyzed in a unique paper, allowing a global view of the topic and emphasizing the need of a multidisciplinary approach. Future learning areas in this topic mainly relate to rapidly increasing the knowledge of imaging studies together with expanding the armamentarium of novel biological and targeting agents in lymphoma patients.

Immune Checkpoint Inhibition in Hodgkin Lymphoma

Intricate systems of checkpoints such as the programmed cell death protein 1 (PD-1)/programmed death ligand 1 (PD-L1) axis regulate adaptive immune responses to protect against tissue damage. However, diverse cancers can exploit these pathways to evade or suppress antitumor immunity, leading to tumor progression. Correspondingly, immune checkpoint inhibitors that block PD-1/PD-L1 signaling have shown marked therapeutic efficacy in certain cancers, such as Hodgkin lymphoma. Reed-Sternberg cells, the hallmark cells of Hodgkin lymphoma, commonly overexpress PD-1 ligands, and recent clinical trials have demonstrated impressive response rates with the PD-1 inhibitors nivolumab and pembrolizumab in relapsed or refractory Hodgkin lymphoma, leading to their FDA approval in this setting. Current efforts are underway to improve clinical responses by incorporating PD-1 inhibitors into earlier treatment regimens and identifying therapeutic agents that synergize with PD-1 inhibitors. This review summarizes our understanding of the PD-1/PD-L1 axis in Hodgkin lymphoma, recent clinical studies of anti-PD-1 monotherapy and promising combination immunotherapy in the pipeline.

The small GTPase RhoU lays downstream of JAK/STAT signaling and mediates cell migration in multiple myeloma

Multiple myeloma is a post-germinal center B-cell neoplasm, characterized by the proliferation of malignant bone marrow plasma cells, whose survival and proliferation is sustained by growth factors and cytokines present in the bone marrow microenvironment. Among them, IL-6 triggers the signal downstream of its receptor, leading to the activation of the JAK/STAT pathway. The atypical GTPase RhoU lays downstream of STAT3 transcription factor and could be responsible for mediating its effects on cytoskeleton dynamics. Here we demonstrate that RHOU is heterogeneously expressed in primary multiple myeloma cells and significantly modulated with disease progression. At the mRNA level, RHOU expression in myeloma patients correlated with the expression of STAT3 and its targets MIR21 and SOCS3. Also, IL-6 stimulation of human myeloma cell lines up-regulated RHOU through STAT3 activation. On the other hand, RhoU silencing led to a decrease in cell migration with the accumulation of actin stress fibers, together with a decrease in cyclin D2 expression and in cell cycle progression. Furthermore, we found that even though lenalidomide positively regulated RhoU expression leading to higher cell migration rates, it actually led to cell cycle arrest probably through a p21 dependent mechanism. Lenalidomide treatment in combination with RhoU silencing determined a loss of cytoskeletal organization inhibiting cell migration, and a further increase in the percentage of cells in a resting phase. These results unravel a role for RhoU not only in regulating the migratory features of malignant plasma cells, but also in controlling cell cycle progression.

The CXCR4-STAT3-IL-10 Pathway Controls the Immunoregulatory Function of Chronic Lymphocytic Leukemia and Is Modulated by Lenalidomide

Chronic lymphocytic leukemia (CLL) cells possess regulatory functions comparable to those of normal B10 cells, a regulatory B cell subset that suppresses effector T-cell function through STAT3-mediated IL-10 production. However, the mechanisms governing IL-10 production by CLL cells are not fully understood. Here, we show that the CXC chemokine ligand 12 (CXCL12)–CXCR4–STAT3 axis regulates IL-10 production by CLL cells and their ability to suppress T-cell effector function through an IL-10 mediated mechanism. Knockdown of STAT3 significantly impaired the ability of CLL cells to produce IL-10. Furthermore, experiments to assess the role of lenalidomide, an immunomodulatory agent with direct antitumor effect as well as pleiotropic activity on the immune system, showed that this agent prevents a CXCL12-induced increase in p-S727-STAT3 and the IL-10 response by CLL cells. Lenalidomide also suppressed IL-10-induced Y705-STAT3 phosphorylation in healthy T cells, thus reversing CLL-induced T-cell dysfunction. We conclude that the capacity of CLL cells to produce IL-10 is mediated by the CXCL12–CXCR4–STAT3 pathway and likely contributes to immunodeficiency in patients. Lenalidomide appears to be able to reverse CLL-induced immunosuppression through including abrogation of the CXCL12–CXCR4–S727–STAT3-mediated IL-10 response by CLL cells and prevention of IL-10-induced phosphorylation of Y705-STAT3 in T cells.

Targeted Therapy: Attacking Cancer with Molecular and Immunological Targeted Agents

Today, personalized cancer therapy with targeted agents has taken center stage, and offers individualized treatment to many. As the mysteries of the genes in a cell's DNA and their specific proteins are defined, advances in the understanding of cancer gene mutations and how cancer evades the immune system have been made. This article provides a basic and simplified understanding of the available (Food and Drug Administration- approved) molecularly and immunologically targeted agents in the USA. Other agents may be available in Asia, and throughout the USA and the world, many more agents are being studied. Nursing implications for drug classes are reviewed.

Neuroprotection by immunomodulatory agents in animal models of Parkinson's disease

Parkinson's disease (PD) is an age-related neurodegenerative disease for which the characteristic motor symptoms emerge after an extensive loss of dopamine containing neurons. The cell bodies of these neurons are present in the substantia nigra, with the nerve terminals being in the striatum. Both innate and adaptive immune responses may contribute to dopaminergic neurodegeneration and disease progression is potentially linked to these. Studies in the last twenty years have indicated an important role for neuroinflammation in PD through degeneration of the nigrostriatal dopaminergic pathway. Characteristic of neuroinflammation is the activation of brain glial cells, principally microglia and astrocytes that release various soluble factors. Many of these factors are proinflammatory and neurotoxic and harmful to nigral dopaminergic neurons. Recent studies have identified several different agents with immunomodulatory properties that protected dopaminergic neurons from degeneration and death in animal models of PD. All of the agents were effective in reducing the motor deficit and alleviating dopaminergic neurotoxicity and, when measured, preventing the decrease of dopamine upon being administered therapeutically after 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, 6-hydroxydopamine, rotenone-lesioning or delivery of adeno-associated virus-α-synuclein to the ventral midbrain of animals. Some of these agents were shown to exert an anti-inflammatory action, decrease oxidative stress, and reduce lipid peroxidation products. Activation of microglia and astrocytes was also decreased, as well as infiltration of T cells into the substantia nigra. Pretreatment with fingolimod, tanshinoine I, dimethyl fumarate, thalidomide, or cocaine- and amphetamine-regulated transcript peptide as a preventive strategy ameliorated motor deficits and nigral dopaminergic neurotoxicity in brain-lesioned animals. Immunomodulatory agents could be used to treat patients with early clinical signs of the disease or potentially even prior to disease onset in those identified as having pre-disposing risk, including genetic factors.

Immunotherapy Strategies Against Multiple Myeloma

Multiple myeloma is a monoclonal B-cell malignancy characterized by an accumulation of malignant plasma cells in the bone marrow, the presence of a monoclonal protein in the serum and/or urine, decreased normal immunoglobulin levels, and lytic bone disease. Patients with multiple myeloma benefit from combination therapy including novel therapeutic agents followed by autologous stem cell transplantation prolonged maintenance therapy. However, multiple myeloma remains incurable; most patients with multiple myeloma will eventually become resistant to chemotherapy, and progression or relapse of the disease is inevitable. Immunotherapy represents a novel therapeutic approach with few adverse effects and good targeting capability that might be a powerful pool to allow long-term control of minimal residual disease. This article reviews the literature evaluating 4 major immunotherapeutic approaches for multiple myeloma including cellular immunotherapy, humoral immunotherapy, radio immunotherapy, and immunomodulation.

Anti-hypersensitivity effects of the phthalimide derivative N-(4methyl-phenyl)-4-methylphthalimide in different pain models in mice

The treatment of chronic pain remains a challenge for clinicians worldwide, independent of its pathogenesis. It motivates several studies attempting to discover strategies to treat the disease. The in silico analysis using molecular docking approach demonstrated that the phthalimide N-(4methyl-phenyl)-4-methylphthalimide (MPMPH-1) presented high affinity to adenylyl-cyclase enzyme (AC). It also prominently reduced the mechanical hypersensitivity of mice challenged by Forskolin, an AC activator. This effect lasted for up to 48h after Forskolin injection, presenting activity longer than MDL-12330A (AC inhibitor). MPMPH-1 was also effective in reducing the hypersensitivity induced by IL-1β, bradykinin, prostaglandin E₂ or epinephrine, chemical mediators that have, among others, AC as pivotal protein in their signalling cascade to induce mechanical-pain behaviour. The compound presented marked inhibition in inflammatory-pain models induced by carrageenan, lipopolysaccharide or complete Freund's adjuvant, including neutrophil migration inhibition. Furthermore, it also seems to act in both peripheral and pain central-control pathways, being also effective in reducing the persistent cancer-pain behaviour induced by melanoma cells in mice. MPMPH-1 could represent a promising pharmacological tool to treat acute and chronic painful diseases, with good bioavailability, local activity, and lack of locomotor-activity interference. Further studies are necessary to determine the exact mechanism of action but it seems to involve AC enzyme as possible target.

Inflammatory and Anti-Inflammatory Equilibrium, Proliferative and Antiproliferative Balance: The Role of Cytokines in Multiple Myeloma

Multiple myeloma (MM) is typically exemplified by a desynchronized cytokine system with increased levels of inflammatory cytokines. We focused on the contrast between inflammatory and anti-inflammatory systems by assessing the role of cytokines and their influence on MM. The aim of this review is to summarize the available information to date concerning this equilibrium to provide an overview of the research exploring the roles of serum cytokines in MM. However, the association between MM and inflammatory cytokines appears to be inadequate, and other functions, such as pro-proliferative or antiproliferative effects, can assume the role of cytokines in the genesis and progression of MM. It is possible that inflammation, when guided by cancer-specific Th1 cells, may inhibit tumour onset and progression. In a Th1 microenvironment, proinflammatory cytokines (e.g., IL-6 and IL-1) may contribute to tumour eradication by attracting leucocytes from the circulation and by increasing CD4 ⁺ T cell activity. Hence, caution should be used when considering therapies that target factors with pro- or anti-inflammatory activity. Drugs that may reduce the tumour-suppressive Th1-driven inflammatory immune response should be avoided. A better understanding of the relationship between inflammation and myeloma will ensure more effective therapeutic interventions.

Targeting the cancer epigenome: synergistic therapy with bromodomain inhibitors

Epigenetic and genomic alterations regulate the transcriptional landscape of cells during cancer onset and progression. Recent clinical studies targeting the epigenetic 'readers' (bromodomains) for cancer therapy have established the effectiveness of bromodomain (BRD) and extraterminal (BET) inhibitors in treating several types of cancer. In this review, we discuss key mechanisms of BET inhibition and synergistic combinations of BET inhibitors with histone deacetylase inhibitors (HDACi), histone methyltransferase inhibitors (HMTi), DNA methyltransferase inhibitors (DNMTi), kinase, B-cell lymphoma 2 (Bcl-2) and proteosome inhibitors, and immunomodulatory drugs for cancer therapy. We also highlight the potential of such combinations to overcome drug resistance, and the evolving approaches to developing novel BET inhibitors.

Immunohistochemical expression of cereblon and MUM1 as potential predictive markers of response to lenalidomide in extranodal marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT lymphoma)

Lenalidomide is an active agent for the treatment of MALT lymphoma. Recently, high expression levels of cereblon (CRBN) and MUM1 have been associated with better response rates in multiple myeloma treated with lenalidomide. However, there are no data on CRBN and MUM1 expression in MALT lymphoma. In the current study, we have systematically investigated a potential correlation of CRBN/MUM1 immunohistochemical expression and response to lenalidomide-based therapy in a series of 46 patients with MALT lymphoma treated at the Medical University Vienna 2009 to 2014. In total, 28% (13/46) of biopsy specimens derived from gastric tissues, while 72% (33/46) originated from extragastric MALT lymphoma. In terms of CRBN, 54% showed high expression (CRBN+, ≥50% positive cells); the remaining 46% were classified as low expression (CRBN-). In contrast to other reports, there was a non-significant trend towards worse response rates in CRBN+ (68% versus 86%, P = 0.161). Relapse rates (P = 0.592) and PFS (P = 0.306) did not differ between CRBN+/CRBN-, but all 3 patients progressing on lenalidomide were CRBN+ and both patients completely lacking CRBN expression responded to treatment. Concerning MUM1, 62% were MUM1-negative (MUM1-) and 38% positive (MUM1+). There was no difference in response to lenalidomide by MUM1-status (MUM1+ 71% versus MUM1- 79%, P = 0.546) and also relapse rates (P = 0.828) and PFS (P = 0.681) did not differ. Interestingly, a subgroup analysis of gastric lymphoma revealed a significantly better PFS for CRBN- and MUM1- patients, respectively (both P < 0.05). To conclude, there was no significant difference in response to lenalidomide between patients with low or high expression of CRBN/MUM1 in a general population of MALT lymphoma, and immunohistochemical CRBN/MUM1 assessment cannot be recommended in the clinical routine.

Lenalidomide-induced eosinophilic pneumonia

Multiple myeloma is a plasma cell dyscrasia accounting for 10% of haematologic malignancies. Lenalidomide is an immunomodulatory drug analogous to thalidomide that is approved for use in patients with myelodysplastic syndrome, and in combination with dexamethasone for refractory or relapsed multiple myeloma. Lenalidomide is preferred to thalidomide because of reduced toxicity, and pulmonary side effects are considered rare. We present, to our knowledge, an unusual and first reported case of a patient with relapsed multiple myeloma who received lenalidomide after autologous stem cell transplant, then developed eosinophilic pneumonia presenting as dyspnoea, peripheral eosinophilia, and bilateral pulmonary opacities. Bronchoscopy with bronchoalveolar lavage was negative for infection, and transbronchial lung biopsies showed eosinophilic pneumonia. After discontinuation of lenalidomide and initiation of prednisone therapy, his dyspnoea improved and eosinophilia resolved; however, symptoms recurred when the drug was restarted at a lower dose, confirming its causative role. In the absence of infection, clinicians should always bear in mind drug toxicity in the differential diagnosis of patients receiving lenalidomide and related agents.

Azacitidine in adult patients with acute myeloid leukemia

Azacitidine is recommended front-line treatment for older patients with acute myeloid leukemia (AML) who are not candidates for intensive treatment regimens, and was recently granted approval in the European Union for treatment of adult AML. Reviewed here is azacitidine experience in AML, including: mechanistic and pharmacokinetic data; safety and efficacy in controlled trials; treatment effects in AML subpopulations defined by disease characteristics; experience in unselected patients treated in the community setting; clinical outcomes relative to other approved AML therapies; and experience with azacitidine-based combination treatment regimens. Collectively, these data suggest that (a) azacitidine may prolong overall survival to a similar or greater extent than do other approved AML treatments, but with less toxicity, (b) azacitidine may be the preferred treatment option for older patients with unfavorable cytogenetics, and (c) experience and outcomes with azacitidine in the clinic are similar to those seen in clinical trials. Continued investigation of combination regimens on an azacitidine backbone is warranted.