Histone deacetylases (HDACs) are master regulators of chromatin remodeling, acting as epigenetic regulators of gene expression. In the last decade, inhibition of HDACs has become a target for ...specific epigenetic modifications related to cancer development. Overexpression of HDAC has been observed in several hematologic malignancies. Therefore, the observation that HDACs might play a role in various hematologic malignancies has brought to the development of HDAC inhibitors as potential antitumor agents. Recently, the class IIb, HDAC6, has emerged as one potential selective HDACi. This isoenzyme represents an important pharmacological target for selective inhibition. Its selectivity may reduce the toxicity related to the off-target effects of pan-HDAC inhibitors. HDAC6 has also been studied in cancer especially for its ability to coordinate a variety of cellular processes that are important for cancer pathogenesis. HDAC6 has been reported to be overexpressed in lymphoid cells and its inhibition has demonstrated activity in preclinical and clinical study of lymphoproliferative disease. Various studies of HDAC6 inhibitors alone and in combination with other agents provide strong scientific rationale for the evaluation of these new agents in the clinical setting of hematological malignancies. In this review, we describe the HDACs, their inhibitors, and the recent advances of HDAC6 inhibitors, their mechanisms of action and role in lymphoproliferative disorders.
Cytokines are a broad group of small regulatory proteins with many biological functions involved in regulating the hematopoietic and immune systems. However, in pathological conditions, ...hyperactivation of the cytokine network constitutes the fundamental event in cytokine release syndrome (CRS). During the last few decades, the development of therapeutic monoclonal antibodies and T-cell therapies has rapidly evolved, and CRS can be a serious adverse event related to these treatments. CRS is a set of toxic adverse events that can be observed during infection or following the administration of antibodies for therapeutic purposes and, more recently, during T-cell-engaging therapies. CRS is triggered by on-target effects induced by binding of chimeric antigen receptor (CAR) T cells or bispecific antibody to its antigen and by subsequent activation of bystander immune and non-immune cells. CRS is associated with high circulating concentrations of several pro-inflammatory cytokines, including interleukins, interferons, tumor necrosis factors, colony-stimulating factors, and transforming growth factors. Recently, considerable developments have been achieved with regard to preventing and controlling CRS, but it remains an unmet clinical need. This review comprehensively summarizes the pathophysiology, clinical presentation, and treatment of CRS caused by T-cell-engaging therapies utilized in the treatment of hematological malignancies.
Bone physiology relies on the delicate balance between resorption and formation of its tissue. Bone resorption depends on a process called osteoclastogenesis in which bone-resorbing cells, i.e., ...osteoclasts, are produced by the differentiation of more undifferentiated progenitors and precursors. This process is governed by two main factors, monocyte colony-stimulating factor (M-CSF) and receptor activator of NFκB ligand (RANKL). While the former exerts a proliferating effect on progenitors/precursors, the latter triggers a differentiation effect on more mature cells of the same lineage. Bone homeostasis requires a perfect space-time coordination of the involved signals. When osteoclastogenesis is poorly balanced with the differentiation of the bone forming counterparts, i.e., osteoblasts, physiological bone remodelling can turn into a pathological state, causing the systematic disruption of bone tissue which results in osteopenia or osteolysis. Examples of these conditions are represented by osteoporosis, Paget's disease, bone metastasis, and multiple myeloma. Therefore, drugs targeting osteoclastogenesis, such as bisphosphonates and an anti-RANKL monoclonal antibody, have been developed and are currently used in the treatment of such diseases. Despite their demonstrated therapeutic efficacy, these agents are unfortunately not devoid of side effects. In this regard, a condition called osteonecrosis of the jaw (ONJ) has been recently correlated with anti-resorptive therapy. In this review we will address the involvement of osteoclasts and osteoclast-related factors in the pathogenesis of ONJ. It is to be hoped that a better understanding of the biological mechanisms underlying bone remodelling will help in the design a medical therapeutic approach for ONJ as an alternative to surgical procedures.
Relapsed/refractory (RR) multiple myeloma (MM) patients are a fragile population because of prolonged drug exposure and advanced age. Preserving a good quality of life is of high priority for these ...patients and the treatment of disease- and treatment-related complications plays a key role in their management. By preventing and limiting MM-induced complications, supportive care improves patients’ outcome. Erythropoietin-stimulating agents and bisphosphonates are well-established supportive strategies, yet novel agents are under investigation, such as anabolic bone agents and activin receptor-like kinase (ALK) inhibitors. The recent dramatic changes in the treatment landscape of MM pose an additional challenge for the routine care of RRMM patients. Multidrug combinations in first and later lines increase the risk for long-lasting toxicities, including adverse cardiovascular and neurological events. Moreover, recently approved first-in-class drugs have unique side-effect profiles, such as ocular toxicity of belantamab mafodotin or gastrointestinal toxicity of selinexor. This review discusses current standards in supportive treatment of RRMM patients, including recommendations in light of the recent SARS-CoV-19 pandemic, and critically looks at the incidence and management of side effects of standard as well as next generation anti-MM agents.
Summary
Novel treatments for multiple myeloma (MM) have shown promising results in clinical trials, but the advantage in unselected patients is still unclear. In order to evaluate whether novel ...therapies impact survival of MM patients, we performed a population‐based analysis on data collected by the Modena Cancer Registry from 1989 to 2009. The analysis evaluated 1206 newly diagnosed MM patients collected in the years 1988–96 (conventional therapy), 1997–05 (high dose melphalan and autologous transplant), and 2006–09 (novel agents era). Both relative survival (RS) and overall survival (OS) improved over the years, but not equally in the three groups. For patients aged <65 years, RS improved in 1997–05 and 2006–09 compared with previous years and a trend to improvement was observed from 1997–05 to 2006–09. For patients aged 65–74 years, RS improved significantly in 2006–09 compared with 1988–96 and 1997–05. No amelioration was observed for patients 75+ years old. OS confirmed RS. In conclusion, the survival of MM patients aged <65 and, in particular, 65–74 years, has improved over time, especially after 2006. This observation provides circumstantial evidence that novel therapies might impact patient survival. Despite the limits of this study, these data refer to an unselected population, giving a picture of every day clinical practice.
To verify whether absolute monocyte count (AMC) and lymphocyte- monocyte ratio (LMR) at diagnosis are valid prognostic parameters in classical Hodgkin lymphoma (cHL).
Data were collected from 1450 ...patients with cHL treated in Israel and Italy from January 1, 1988, through December 31, 2007.
The median age of the patients was 33 years (range, 17-72 years), and 70% (1017) of the patients had nodular sclerosis (NS); the median follow-up duration was 87 months. The best cutoff value for AMC was 750 cells/mm3, and the best ratio for LMR was 2.1. The adverse prognostic impact of an AMC of more than 750 cells/mm3 was confirmed for the entire cohort, and its clinical significance was particularly evident in patients with NS histology. The progression-free survival (PFS) at 10 years for an AMC of more than 750 cells/mm3 was 65% (56%-72%), and the PFS at 10 years for an AMC of 750 cells/mm3 or less was 81% (76%-84%; P<.001). The overall survival (OS) at 10 years for an AMC of more than 750 cells/mm3 was 78% (70%-85%), and the OS at 10 years for an AMC of 750 cells/mm3 or less was 88% (84%-90%; P=.01). In multivariate analysis, both AMC and LMR maintained prognostic significance for PFS (hazard ratio HR, 1.54, P=.006, and HR, 1.50, P=.006) after adjusting for the international prognostic score, whereas the impact on OS was confirmed (HR, 1.56; P=.04) only in patients with NS and an AMC of more than 750 cells/mm3.
This study confirms that AMC has prognostic value in cHL that is particularly significant in patients with NS subtype histology. This finding links the known impact of macrophages and monocytes in Hodgkin lymphoma with routine clinical practice.
In this study we assessed the prognostic significance of absolute monocyte count and selected the best cut-off value at diagnosis in a large cohort of patients with diffuse large B-cell lymphoma. ...Data were retrieved for therapy-naïve patients with diffuse large B-cell lymphoma followed in Israel and Italy during 1993-2010. A final cohort of 1017 patients was analyzed with a median follow up of 48 months and a 5-year overall survival rate of 68%. The best absolute monocyte count cut-off level was 630/mm(3) and the 5-year overall survival for patients with counts below this cut-off was 71%, whereas it was 59% for those with a count >630 mm(3) (P=0.0002). Of the 1017 patients, 521 (51%) were treated with chemo-immunotherapy, and in this cohort, using multivariate analysis, elevated monocyte count retained a negative prognostic value even when adjusted for International Prognostic Index (HR1.54, P=0.009). This large study shows that a simple parameter such as absolute monocyte count (>630/mm(3)) can easily be used routinely in the evaluation of newly diagnosed diffuse large B-cell lymphoma to identify high-risk patients with a worse survival in the rituximab era.
To compare doxorubicin, bleomycin, vinblastine, dacarbazine (ABVD) versus bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone (BEACOPP) versus ...cyclophosphamide, lomustine, vindesine, melphalan, prednisone, epidoxirubicin, vincristine, procarbazine, vinblastine, and bleomycin (COPPEBVCAD; CEC) for advanced Hodgkin's lymphoma (HL).
Three hundred seven patients with advanced HL (stage IIB, III, and IV) were randomly assigned to receive six courses of ABVD, four escalated plus two standard courses of BEACOPP, or six courses of CEC, plus a limited radiation therapy program.
After a median follow-up of 41 months, BEACOPP resulted in a superior progression-free survival (PFS), with a significant reduction in risk of progression (hazard ratio HR = 0.50) compared with ABVD. No differences between BEACOPP and CEC, or CEC and ABVD were observed. The 5-year PFS was 68% (95% CI, 56% to 78%), 81% (95% CI, 70% to 89%), and 78% (95% CI, 68% to 86%), for ABVD, BEACOPP, and CEC, respectively (BEACOPP v ABVD, P = .038; CEC v ABVD and BEACOPP v CEC, P = not significant NS). The 5-year overall survival was 84% (95% CI, 69% to 92%), 92% (95% CI, 84% to 96%), and 91% (95% CI, 81% to 96%) for ABVD, BEACOPP, and CEC, respectively (P = NS). BEACOPP and CEC resulted in higher rates of grade 3-4 neutropenia than ABVD (P = .016); BEACOPP was associated with higher rates of severe infections than ABVD and CEC (P = .003).
As adopted in this study BEACOPP is associated with a significantly improved PFS compared with ABVD, with a predictable higher acute toxicity.
Understanding the pathogenesis of cancer-related bone disease is crucial to the discovery of new therapies. Here we identify activin A, a TGF-β family member, as a therapeutically amenable target ...exploited by multiple myeloma (MM) to alter its microenvironmental niche favoring osteolysis. Increased bone marrow plasma activin A levels were found in MM patients with osteolytic disease. MM cell engagement of marrow stromal cells enhanced activin A secretion via adhesion-mediated JNK activation. Activin A, in turn, inhibited osteoblast differentiation via SMAD2-dependent distal-less homeobox-5 down-regulation. Targeting activin A by a soluble decoy receptor reversed osteoblast inhibition, ameliorated MM bone disease, and inhibited tumor growth in an in vivo humanized MM model, setting the stage for testing in human clinical trials.
The phosphoinositide 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathway mediates multiple myeloma (MM) cell proliferation, survival, and development of drug resistance, underscoring the ...role of mTOR inhibitors, such as rapamycin, with potential anti-MM activity. However, recent data show a positive feedback loop from mTOR/S6K1 to Akt, whereby Akt activation confers resistance to mTOR inhibitors. We confirmed that suppression of mTOR signaling in MM cells by rapamycin was associated with upregulation of Akt phosphorylation. We hypothesized that inhibiting this positive feedback by a potent Akt inhibitor perifosine would augment rapamycin-induced cytotoxicity in MM cells. Perifosine inhibited rapamycin-induced phosphorylated Akt, resulting in enhanced cytotoxicity in MM.1S cells even in the presence of interleukin-6, insulin-like growth factor-I, or bone marrow stromal cells. Moreover, rapamycin-induced autophagy in MM.1S MM cells, as evidenced by electron microscopy and immunocytochemistry, was augmented by perifosine. Combination therapy increased apoptosis detected by Annexin V/propidium iodide analysis and caspase/poly(ADP-ribose) polymerase cleavage. Importantly, in vivo antitumor activity and prolongation of survival in a MM mouse xenograft model after treatment was enhanced with combination of nanoparticle albumin-bound-rapamycin and perifosine. Utilizing the in silico predictive analysis, we confirmed our experimental findings of this drug combination on PI3K, Akt, mTOR kinases, and the caspases. Our data suggest that mutual suppression of the PI3K/Akt/mTOR pathway by rapamycin and perifosine combination induces synergistic MM cell cytotoxicity, providing the rationale for clinical trials in patients with relapsed/refractory MM. Mol Cancer Ther; 9(4); 963-75. (c)2010 AACR.
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