Dinaciclib synergizes with BH3 mimetics targeting BCL-2 and BCL-XL in multiple myeloma cell lines partially dependent on MCL-1 and in plasma cells from patients.

A better understanding of multiple myeloma (MM) biology has led to the development of novel therapies. However, MM is still an incurable disease and new pharmacological strategies are needed. Dinaciclib, a multiple cyclin-dependent kinase (CDK) inhibitor, which inhibits CDK1, 2, 5 and 9, displays significant antimyeloma activity as found in phase II clinical trials. In this study, we have explored the mechanism of dinaciclib-induced death and evaluated its enhancement by different BH3 mimetics in MM cell lines as well as in plasma cells from MM patients. Our results indicate a synergistic effect of dinaciclib-based combinations with B-cell lymphoma 2 or B-cell lymphoma extra-large inhibitors, especially in MM cell lines with partial dependence on myeloid cell leukemia sequence 1 (MCL-1). Simultaneous treatment with dinaciclib and BH3 mimetics ABT-199 or A-1155463 additionally showed a synergistic effect in plasma cells from MM patients, ex vivo. Altered MM cytogenetics did not affect dinaciclib response ex vivo, alone or in combined treatment, suggesting that these combinations could be a suitable therapeutic option for patients bearing cytogenetic alterations and poor prognosis. This work also opens the possibility to explore cyclin-dependent kinase 9 inhibition as a targeted therapy in MM patients overexpressing or with high dependence on MCL-1.

Ecto-calreticulin expression in multiple myeloma correlates with a failed anti-tumoral immune response and bad prognosis.

Immunogenic cell death (ICD) has been proposed to be a crucial process for antitumor immunosurveillance. ICD is characterized by the exposure and emission of Damage Associated Molecular Patterns (DAMP), including calreticulin (CRT). A positive correlation between CRT exposure or total expression and improved anticancer immunosurveillance has been found in certain cancers, usually accompanied by favorable patient prognosis. In the present study, we sought to evaluate CRT levels in the plasma membrane of CD38+ bone marrow mononuclear cells (BMMCs) isolated from 71 patients with varying degrees of multiple myeloma (MM) disease and examine the possible relationship between basal CRT exposure and the bone marrow immune microenvironment, as well as its connection with different clinical markers. Data show that increased levels of cell surface-CRT were associated with more aggressive clinical features and with worse clinical prognosis in MM. High CRT expression in MM cells was associated with increased infiltration of NK cells, CD8+ T lymphocytes and dendritic cells (DC), indicative of an active anti-tumoral immune response, but also with a significantly higher presence of immunosuppressive Treg cells and increased expression of PD-L1 in myeloma cells.

Relevance of infections on the outcomes of patients with myelodysplastic syndromes, chronic myelomonocytic leukemia, and acute myeloid leukemia treated with hypomethylating agents: a cohort study from the GESMD.

Background: The consequences of infectious toxicity of hypomethylating agents (HMAs) on overall survival (OS) of patients diagnosed with high-risk myeloid neoplasms have not been thoroughly investigated. Objectives: We aimed to evaluate whether infectious events (IEs) negatively influenced the results of HMA treatment in a real-world setting. Design: Observational study. Methods: We obtained data from 412 non-selected consecutive patients from 23 Spanish hospitals who were diagnosed with high-risk myelodysplastic syndrome, chronic myelomonocytic leukemia, or acute myeloid leukemia and were treated with HMA. HMAs received after chemotherapy or stem cell transplant were excluded. All IEs were recorded. Outcomes included OS, modifications to the pre-planned treatment, incidence and characteristics of IEs, hospitalization, red blood cell transfusions, and factors associated with infection. Results: The rate of infection was 1.2 per patient/year. Next-cycle delay (p = 0.001) and hospitalizations (p = 0.001) were significantly influenced by IEs. Transfusion requirements during each cycle were significantly higher after infection compared with cycles without infection (coefficient = 1.55 [95% confidence interval (CI) = 1.26-1.84], p < 0.001). The median number of cycles was lower in patients experiencing any infection during the first four cycles (5 [3-8] versu 8 [5-16], p < 0.001). In the multivariable analysis, factors associated with lower OS were having any infection during the first four cycles (hazard ratio (HR) = 1.43 [95% CI = 1.09-1.88], p = 0.01), bone marrow blasts ⩾30% (HR = 2.13 [95% CI = 1.14-3.96], p = 0.01), adverse cytogenetics (HR = 1.70 [95% CI = 1.30-2.24], p < 0.001), and platelet count <50 × 109/l (HR = 1.69 [95% CI = 1.3-2.2], p < 0.001). BM blasts >20% (HR = 1.57 [95% CI = 1.19-2.01], p < 0.001) and adverse cytogenetics (HR = 1.7 [95% CI = 1.35-2.14], p < 0.001) were associated with infection, whereas hemoglobin >9 g/dl (HR = 0.65 [95% CI = 0.51-0.82], p < 0.001) and higher platelet count (HR = 0.997 [95% CI = 0.996-0.998], p = 0.016) protected from it. Conclusion: HMA infectious toxicity worsens OS, hinders the adherence to antineoplastic treatment and results in significant morbidity. Preventive strategies are fundamental in vulnerable patients.

Myelodysplastic syndromes with 20q deletion: incidence, prognostic value and impact on response to azacitidine of ASXL1 chromosomal deletion and genetic mutations.

In myelodysplastic syndromes (MDS), the 20q deletion [del(20q)] may cause deletion of the ASXL1 gene. We studied 153 patients with MDS and del(20q) to assess the incidence, prognostic value and impact on response to azacitidine (AZA) of ASXL1 chromosomal alterations and genetic mutations. Additionally, in vitro assay of the response to AZA in HAP1 (HAP1WT ) and HAP1 ASXL1 knockout (HAP1KN ) cells was performed. ASXL1 chromosomal alterations were detected in 44 patients (28·5%): 34 patients (22%) with a gene deletion (ASXL1DEL ) and 10 patients (6·5%) with additional gene copies. ASXL1DEL was associated with a lower platelet count. The most frequently mutated genes were U2AF1 (16%), ASXL1 (14%), SF3B1 (11%), TP53 (7%) and SRSF2 (6%). ASXL1 alteration due to chromosomal deletion or genetic mutation (ASXL1DEL /ASXL1MUT ) was linked by multivariable analysis with shorter overall survival [hazard ratio, (HR) 1·84; 95% confidence interval, (CI): 1·11-3·04; P = 0·018] and a higher rate for acute myeloid leukaemia progression (HR 2·47; 95% CI: 1·07-5·70, P = 0·034). ASXL1DEL /ASXL1MUT patients were correlated by univariable analysis with a worse response to AZA. HAP1KN cells showed more resistance to AZA compared to HAP1WT cells. In conclusion, ASXL1 alteration exerts a negative impact on MDS with del(20q) and could become useful for prognostic risk stratification and treatment decisions.

Expanded NK cells from umbilical cord blood and adult peripheral blood combined with daratumumab are effective against tumor cells from multiple myeloma patients.

In this study we evaluated the potential of expanded NK cells (eNKs) from two sources combined with the mAbs daratumumab and pembrolizumab to target primary multiple myeloma (MM) cells ex vivo. In order to ascertain the best source of NK cells, we expanded and activated NK cells from peripheral blood (PB) of healthy adult donors and from umbilical cord blood (UCB). The resulting expanded NK (eNK) cells express CD16, necessary for carrying out antibody-dependent cellular cytotoxicity (ADCC). Cytotoxicity assays were performed on bone marrow aspirates of 18 MM patients and 4 patients with monoclonal gammopathy of undetermined significance (MGUS). Expression levels of PD-1 on eNKs and PD-L1 on MM and MGUS cells were also quantified. Results indicate that most eNKs obtained using our expansion protocol express a low percentage of PD-1+ cells. UCB eNKs were highly cytotoxic against MM cells and addition of daratumumab or pembrolizumab did not further increase their cytotoxicity. PB eNKs, while effective against MM cells, were significantly more cytotoxic when combined with daratumumab. In a minority of cases, eNK cells showed a detectable population of PD1+ cells. This correlated with low cytotoxic activity, particularly in UCB eNKs. Addition of pembrolizumab did not restore their activity. Results indicate that UCB eNKs are to be preferentially used against MM in the absence of daratumumab while PB eNKs have significant cytotoxic advantage when combined with this mAb.

A new prognostic model identifies patients aged 80 years and older with diffuse large B-cell lymphoma who may benefit from curative treatment: A multicenter, retrospective analysis by the Spanish GELTAMO group.

The means of optimally managing very elderly patients with diffuse large B-cell lymphoma (DLBCL) has not been established. We retrospectively analyzed 252 patients aged 80-100 years, diagnosed with DLBCL or grade 3B follicular lymphoma, treated in 19 hospitals from the GELTAMO group. Primary objective was to analyze the influence of the type of treatment and comorbidity scales on progression-free survival (PFS) and overall survival (OS). One hundred sixty-three patients (63%) were treated with chemotherapy that included anthracyclines and/or rituximab, whereas 15% received no chemotherapeutic treatment. With a median follow-up of 44 months, median PFS and OS were 9.5 and 12.5 months, respectively. In an analysis restricted to the 205 patients treated with any kind of chemotherapy, comorbidity scales did not influence the choice of treatment type significantly. Independent factors associated with better PFS and OS were: age < 86 years, cumulative illness rating scale (CIRS) score < 6, intermediate risk (1-2) R-IPI, and treatment with R-CHOP at full or reduced doses. We developed a prognostic model based on the multivariate analysis of the 108 patients treated with R-CHOP-like: median OS was 45 vs. 12 months (P = .001), respectively, for patients with 0-1 vs. 2-3 risk factors (age > 85 years, R-IPI 3-5 or CIRS > 5). In conclusion, treatment with R-CHOP-like is associated with good survival in a significant proportion of patients. We have developed a simple prognostic model that may aid the selection patients who could benefit from a curative treatment, although it needs to be validated in larger series.