Erratum: Addition and Correction to "High-Performance Concurrent Chemo-Immuno-Radiotherapy for the Treatment of Hematologic Cancer through Selective High-Affinity Ligand Antibody Mimic-Functionalized Doxorubicin-Encapsulated Nanoparticles".

[This corrects the article DOI: 10.1021/acscentsci.8b00746.].

Impact of diagnosis to treatment interval in patients with newly diagnosed mantle cell lymphoma.

The prognostic relevance of diagnosis to treatment interval (DTI) in patients with newly diagnosed mantle cell lymphoma (MCL) is unknown. Hence, we sought to evaluate the impact of DTI on outcomes in MCL using 3 large datasets (1) the University of Iowa/Mayo Clinic Specialized Program of Research Excellence Molecular Epidemiology Resource, (2) patients enrolled in the ALL Age Asthma Cohort/CALGB 50403, and (3) a multisitecohort of patients with MCL. Patients were a priori divided into 2 groups, 0 to 14 days (short DTI) and 15 to 60 days (long DTI). The patients in whom observation was deemed appropriate were excluded. One thousand ninety-seven patients newly diagnosed with MCL and available DTI were included in the study. The majority (73%) had long DTI (n=797). Patients with short DTI had worse eastern cooperative oncology group performance status (ECOG PS ≥2), higher lactate dehydrogenase, bone marrow involvement, more frequent B symptoms, higher MCL International Prognostic Index (MIPI ≥6.2), and were less likely to receive intensive induction therapy than long DTI group. The median progression-free survival (2.5 years vs 4.8 years, p<0.0001) and overall survival (7.8 years vs. 11.8 years, p<0.0001) were significantly inferior in the short DTI group than the long DTI cohort and remained significant for progression-free survival and overall survival in multivariable analysis. We show that the DTI is an important prognostic factor in patients newly diagnosed with MCL and is strongly associated with adverse clinical factors and poor outcomes. DTI should be reported in all the patients newly diagnosed with MCL who are enrolling in clinical trials and steps must be taken to ensure selection bias is avoided.

Combination of Atezolizumab and Obinutuzumab in Patients with Relapsed/Refractory Follicular Lymphoma and Diffuse Large B-Cell Lymphoma: Results from a Phase 1b Study.

BACKGROUND: This was an open-label, phase 1b study assessing the safety, tolerability, preliminary efficacy and pharmacokinetics of the combination of atezolizumab and obinutuzumab in patients with relapsed/refractory follicular lymphoma (FL) or diffuse large B-cell lymphoma (DLBCL). There is a mechanistic rationale suggesting that this combination may enhance recruitment of both innate and adaptive immunity and be effective against CD20+ B-cell malignancies. MATERIALS AND METHODS: The study consisted of a safety evaluation stage and an expansion stage. Patients received obinutuzumab 1000 mg intravenously (IV) in cycle (C) 1, obinutuzumab plus atezolizumab 1200 mg IV for C2-8, and atezolizumab only from C9. Primary endpoints were to identify a recommended phase 2 dose (RP2D) for atezolizumab, and safety and tolerability in the safety and expansion stages. RESULTS: A total of 49 patients were enrolled (FL, n = 26; DLBCL, n = 23), with a median of 2 prior lines of treatment. The RP2D for atezolizumab was 1200 mg IV every 3 weeks. Adverse events reported in ≥ 20% of patients were fatigue (15 patients [31%]), nausea (13 patients [27%]), cough, and diarrhea (10 patients [20%] each). Objective response rate was 54% in the FL cohort (complete response [CR] rate: 23%) and 17% in the DLBCL cohort (CR: 4%). Median progression-free survival was 9 months for FL and 3 months for DLBCL. Median overall survival was not estimable for FL and 9 months for DLBCL. CONCLUSION: The combination of obinutuzumab and atezolizumab was determined to be safe and tolerable, with no new toxicities observed.

Safety and Efficacy of Engineered Toxin Body MT-3724 in Relapsed or Refractory B-cell Non-Hodgkin's Lymphomas and Diffuse Large B-cell Lymphoma.

MT-3724, a novel engineered toxin body comprised of an anti-CD20 single-chain variable fragment genetically fused to Shiga-like Toxin A subunit, is capable of binding to and internalizing against CD20, inducing cell killing via permanent ribosomal inactivation. This study evaluated MT-3724 in patients with relapsed/refractory B-cell non-Hodgkin lymphoma (r/rNHL). This open-label, multiple-dose phase Ia/b trial included a dose escalation in patients with r/rNHL according to a standard 3+3 design. Primary objectives were to determine the MTD and pharmacokinetics/pharmacodynamics. In a dose expansion study at MTD in serum rituximab-negative patients with diffuse large B-cell lymphoma (DLBCL), primary objectives were safety, tolerability, and pharmacokinetics/pharmacodynamics. Twenty-seven patients enrolled. MTD was 50 µg/kg/dose with 6,000 µg/dose cap. Thirteen patients experienced at least one grade ≥3 treatment-related adverse events; the most common grade ≥3 event was myalgia (11.1%). Two patients (75 µg/kg/dose) experienced grade 2 treatment-related capillary leak syndrome. Overall objective response rate was 21.7%. In serum rituximab-negative patients with DLBCL or composite DLBCL (n = 12), overall response rate was 41.7% (complete response, n = 2; partial response, n = 3). In patients with detectable baseline peripheral B cells, treatment resulted in dose-dependent B-cell depletion. The proportion of patients with anti-drug antibodies (ADA) increased during treatment and the majority appeared to be neutralizing based on an in vitro assay; nevertheless, tumor regression and responses were observed. MT-3724 demonstrated efficacy at the MTD in this population of previously treated patients with r/rDLBCL, with mild-to-moderate immunogenic safety events. Significance: This work describes the safety and efficacy of a new pharmaceutical pathway that could provide a treatment option for a subset of patients with a critical unmet therapeutic need. The study drug, MT-3724, is capable of targeting B-cell lymphomas via a unique, potent cell-killing mechanism that appears to be promising.

Early relapse identifies MCL patients with inferior survival after intensive or less intensive frontline therapy.

Although an expanding array of effective treatments has resulted in recent improvement in survival of patients with mantle cell lymphoma (MCL), outcomes remain heterogeneous, and identification of prognostic factors remains a priority. We assessed the prognostic impact of time to progression of disease (POD) after first-line therapy among 455 patients with relapsed MCL. Patients were categorized by duration of first remission as PRF/POD6, defined as progressive disease during induction or POD within 6 months of diagnosis (n = 65; 14%); POD6-24, defined as POD between 6 and 24 months after diagnosis (n = 153; 34%); and POD>24, defined as POD >24 months after diagnosis (n = 237; 53%). The median overall survival from POD (OS2) was 1.3 years (95% confidence interval [CI], 0.9-2.4) for patients with PRF/POD6, 3 years (95% CI, 2-6.8) for those with POD6-24, and 8 years (95% CI, 6.2-NR) for those with POD>24. Median OS2 was inferior in patients with early POD (defined as PRF/POD6 or POD6-24) after both intensive and less intensive frontline treatment. The prognostic performance of time until POD was replicated in an independent cohort of 245 patients with relapsed MCL, with median OS2 of 0.3 years (95% CI, 0.1-0.5) for PRF/POD6, 0.8 years (95% CI, 0.6-0.9) for POD6-24, and 2.4 years (95% CI 2.1-2.7) for POD>24. Early POD is associated with inferior OS2 in patients with relapsed MCL, identifying a high-risk population for future prospective studies.

Equal access to care and nurse navigation leads to equitable outcomes for minorities with aggressive large B-cell lymphoma.

BACKGROUND: Aggressive large B-cell lymphomas (LBCLs) are curable, but previous studies have shown inferior outcomes in minorities. Nurse navigation programs can improve patient outcomes by providing patient support. This study presents the outcomes of White and minority patients with aggressive LBCL at an institution with an active nurse navigation program. METHODS: The authors prospectively collected baseline characteristics, treatment regimens, and outcome data for patients with aggressive LBCL. Navigation encounters were characterized as low or high intensity. Overall survival (OS) and progression-free survival (PFS) were calculated with Kaplan-Meier methods. Baseline characteristics were compared with Fisher exact tests. RESULTS: Two hundred four consecutive patients (47 minority patients and 157 White patients) were included. Results were presented as minorities versus Whites. There were no differences in prognostic scores (Revised International Prognostic Index score of 3-5, 43% vs 47%; P = .50), frontline chemotherapy (98% vs 96%; P = .68), or the incidence of relapsed/refractory disease (40% vs 38%; P = .74). For relapsed/refractory LBCL, similar proportions of patients underwent hematopoietic stem cell transplantation (32% vs 29%; P > .99) or chimeric antigen receptor T-cell therapy (16% vs 19%; P > .99). Enrollment in clinical trials was comparable (17% vs 14%; P = .64). More than 85% received nurse navigation, but minorities had higher intensity navigation encounters (42% vs 21%; P = .01). The 2-year OS rates were 81% and 76% for minorities and Whites, respectively (P = .27); the 2-year PFS rates were 62% and 65%, respectively (P = .78). CONCLUSIONS: This study shows similar survival between Whites and minorities with aggressive LBCL, which was likely due to equal access to guideline-concordant therapy. Minorities received higher intensity navigation encounters, which may have helped them to overcome socioeconomic disadvantages.

Multi-center analysis of practice patterns and outcomes of younger and older patients with mantle cell lymphoma in the rituximab era.

Clinical outcomes and predictors of survival in patients with newly diagnosed mantle cell lymphoma (MCL) treated in the rituximab era (2000-2015) at 12 US academic centers were assessed to identify determinants of survival across age groups. Objectives were to characterize and compare practice patterns, outcomes and prognostic factors for survival in younger patients (age < 65) and older patients (age ≥ 65 years). Among 1162 patients included, 697 were younger and 465 were older. In younger patients, 2-year progression free survival (PFS) and overall survival (OS) rates were 79% and 92% respectively; blastoid histology, ECOG ≥ 2, and lack of maintenance rituximab (MR) remained statistically relevant to poor OS on univariate analysis (UVA) and multivariate analysis (MVA). In older patients, 2-year PFS and OS rates were 67% and 86% respectively; lack of maintenance rituximab remained significantly associated with inferior PFS and OS on UVA and MVA (p < 0.001). Two-year PFS rates were 79%, and 67% and 2-year OS rates were 92% and 86% for ages < 65 and ≥ 65 respectively (p < 0.001). First-line high-dose cytarabine exposure and/or MR lessened the negative impact of age on survival. Taken collectively, survival outcomes for older patients remain inferior to those of younger patients in the rituximab era. However, maintenance rituximab and potentially high-dose cytarabine-based induction can mitigate the negative impact of age on survival.

Intensive induction regimens after deferring initial therapy for mantle cell lymphoma are not associated with improved survival.

INTRODUCTION: While most patients with mantle cell lymphoma (MCL) receive therapy shortly after diagnosis, a subset of patients with indolent-behaving disease can safely defer treatment. In this subgroup, we evaluated the importance of treatment intensity in patients with MCL who defer initial therapy. METHODS: Out of 1134 patients with MCL from 12 academic centers, we analyzed 219 patients who initiated therapy at least 90 days after diagnosis. Patients who received induction with high-dose cytarabine and/or autologous stem cell transplantation (ASCT) in first remission were considered to have received intensive therapy (n = 88) while all other approaches were non-intensive (n = 131). RESULTS: There was no difference in progression-free (PFS; P = .224) or overall survival (OS; P = .167) in deferred patients who received non-intensive vs. intensive therapy. Additionally, univariate and multivariate Cox proportional hazards models were performed for PFS and OS. Treatment at an academic center (HR 0.43, P = .015) was associated with improved OS in both univariate and multivariate models, while intensity of treatment was not associated with improved OS in either model. CONCLUSIONS: These results indicate that intensified initial treatment is not associated with improved survival after deferring initial therapy, although prospective studies are needed to determine which of these patients with MCL may benefit from intensive therapy.

Ibrutinib treatment via alternative administration in a patient with chronic lymphocytic leukemia and dysphagia.

INTRODUCTION: Ibrutinib is a small molecule inhibitor of Bruton's tyrosine kinase indicated for the treatment of a variety of B-cell malignancies including chronic lymphocytic leukemia, mantle cell lymphoma, marginal zone lymphoma, and Waldenstrom's macroglobulinemia. These indolent hematologic malignancies are considered diseases of the elderly, a population that may have dysphagia leading to difficulty swallowing tablets and capsules. Ibrutinib is currently not available in a liquid oral dosage form. We report the utilization and clinical outcomes associated with alternative administration of ibrutinib capsules in a patient with chronic lymphocytic leukemia and significant dysphagia. CASE REPORT: An 86-year old female requiring chronic lymphocytic leukemia-directed therapy due to a rising absolute lymphocyte count and worsening, transfusion-dependent anemia with a past medical history of dementia and dysphagia, was initiated on ibrutinib. MANAGEMENT & OUTCOME: Due to the patient's significant inability to swallow, ibrutinib capsules were administered via an alternative method by opening them and sprinkling onto soft food or applesauce. With ibrutinib therapy, the patient has had a significant clinical response in her chronic lymphocytic leukemia as evidenced by her decreased absolute lymphocyte count and achieving transfusion independence with improvements in hemoglobin. DISCUSSION: Ibrutinib administration via this alternative method resulted in an initial clinical response in the treatment of our patient's chronic lymphocytic leukemia as evidenced by a decreasing absolute lymphocyte count and improved anemia that achieved transfusion independence. The patient has maintained this response to therapy after approximately 1 year at the time of manuscript preparation.

Trispecific natural killer cell nanoengagers for targeted chemoimmunotherapy.

Activation of the innate immune system and natural killer (NK) cells has been a key effort in cancer immunotherapy research. Here, we report a nanoparticle-based trispecific NK cell engager (nano-TriNKE) platform that can target epidermal growth factor receptor (EGFR)-overexpressing tumors and promote the recruitment and activation of NK cells to eradicate these cancer cells. Moreover, the nanoengagers can deliver cytotoxic chemotherapeutics to further improve their therapeutic efficacy. We have demonstrated that effective NK cell activation can be achieved by the spatiotemporal coactivation of CD16 and 4-1BB stimulatory molecules on NK cells with nanoengagers, and the nanoengagers are more effective than free antibodies. We also show that biological targeting, either through radiotherapy or EGFR, is critical to the therapeutic effects of nanoengagers. Last, EGFR-targeted nanoengagers can augment both NK-activating agents and chemotherapy (epirubicin) as highly effective anticancer agents, providing robust chemoimmunotherapy.

Anti-CD30 CAR-T Cell Therapy in Relapsed and Refractory Hodgkin Lymphoma.

PURPOSE: Chimeric antigen receptor (CAR) T-cell therapy of B-cell malignancies has proved to be effective. We show how the same approach of CAR T cells specific for CD30 (CD30.CAR-Ts) can be used to treat Hodgkin lymphoma (HL). METHODS: We conducted 2 parallel phase I/II studies (ClinicalTrials.gov identifiers: NCT02690545 and NCT02917083) at 2 independent centers involving patients with relapsed or refractory HL and administered CD30.CAR-Ts after lymphodepletion with either bendamustine alone, bendamustine and fludarabine, or cyclophosphamide and fludarabine. The primary end point was safety. RESULTS: Forty-one patients received CD30.CAR-Ts. Treated patients had a median of 7 prior lines of therapy (range, 2-23), including brentuximab vedotin, checkpoint inhibitors, and autologous or allogeneic stem cell transplantation. The most common toxicities were grade 3 or higher hematologic adverse events. Cytokine release syndrome was observed in 10 patients, all of which were grade 1. No neurologic toxicity was observed. The overall response rate in the 32 patients with active disease who received fludarabine-based lymphodepletion was 72%, including 19 patients (59%) with complete response. With a median follow-up of 533 days, the 1-year progression-free survival and overall survival for all evaluable patients were 36% (95% CI, 21% to 51%) and 94% (95% CI, 79% to 99%), respectively. CAR-T cell expansion in vivo was cell dose dependent. CONCLUSION: Heavily pretreated patients with relapsed or refractory HL who received fludarabine-based lymphodepletion followed by CD30.CAR-Ts had a high rate of durable responses with an excellent safety profile, highlighting the feasibility of extending CAR-T cell therapies beyond canonical B-cell malignancies.

Positron Emission Tomography-Directed Therapy for Patients With Limited-Stage Diffuse Large B-Cell Lymphoma: Results of Intergroup National Clinical Trials Network Study S1001.

PURPOSE: Diffuse large B-cell lymphoma (DLBCL) presents as a limited-stage disease in 25% to 30% of patients, with better overall survival (OS) than that for advanced-stage disease but with continuous relapse regardless of treatment approach. The preferred treatment is abbreviated rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) and radiation therapy. On the basis of promising results of positron emission tomography (PET)-directed treatment approaches, we designed a National Clinical Trials Network (NCTN) study to improve outcomes and decrease toxicity. METHODS: Patients with nonbulky (< 10 cm) stage I/II untreated DLBCL received 3 cycles of standard R-CHOP therapy and underwent a centrally reviewed interim PET/computed tomography scan (iPET). Those with a negative iPET proceeded with 1 additional cycle of R-CHOP, whereas those with a positive iPET received involved field radiation therapy followed by ibritumomab tiuxetan radioimmunotherapy. RESULTS: Of 158 patients enrolled, 132 were eligible and 128 underwent iPET, which was positive in 14 (11%) of the patients. With a median follow-up of 4.92 years (range, 1.1-7.7 years), only 6 patients progressed and 3 died as a result of lymphoma. Eleven patients died as a result of nonlymphoma causes at a median age of 80 years. The 5-year progression-free survival estimate was 87% (95% CI, 79% to 92%) and the OS estimate was 89% (95% CI, 82% to 94%), with iPET-positive and iPET-negative patients having similar outcomes. CONCLUSION: To our knowledge, S1001 is the largest prospective study in the United States of limited-stage DLBCL in the rituximab era, with the best NCTN results in this disease subset. With PET-directed therapy, 89% of the patients with a negative iPET received R-CHOP × 4, and only 11% had a positive iPET and required radiation, with both groups having excellent outcomes. The trial establishes R-CHOP × 4 alone as the new standard approach to limited-stage disease for the absolute majority of patients.

ABVD followed by BV consolidation in risk-stratified patients with limited-stage Hodgkin lymphoma.

Approximately 90% of limited-stage Hodgkin lymphoma (HL) patients are projected to be cured with standard therapy, but many do not live their expected life span because of late treatment-related complications. New treatment paradigms are needed to reduce the use of radiation therapy (RT) as well as conventional chemotherapy drugs while improving upon current standard-of-care survival outcomes. In this phase 2 multicenter study, patients with non-bulky limited-stage HL received doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) followed by brentuximab vedotin (BV) consolidation. Forty-one patients were enrolled, and patient characteristics included median age of 29 years (range, 19 to 67 years), 58% were female, 45% had unfavorable disease, and 98% had stage II disease. Based on positron emission tomography (PET)-based risk stratification, patients received 2 to 6 cycles of ABVD followed by 6 cycles of BV. After ABVD followed by BV, 95% of evaluable patients (37 out of 39; 95% confidence interval [CI], 83%-99%) achieved PET-negative status. In the intent-to-treat patient population, the estimated 3-year progression-free survival (PFS) rate was 92%, and the overall survival (OS) rate was 97%, with a median follow-up of 47 months. All 37 patients who achieved negative PET status after BV consolidation effectively avoided RT and remain in remission with estimated 3-year PFS and OS rates of 100%. In conclusion, BV demonstrates encouraging clinical activity when it follows ABVD therapy in limited-stage HL. Early incorporation of BV may reduce the use of RT as well as conventional chemotherapy drugs while achieving favorable survival outcomes in risk-stratified patients with non-bulky limited-stage HL. This trial was registered at www.clinicaltrials.gov as #NCT01578967.

Pretargeted delivery of PI3K/mTOR small-molecule inhibitor-loaded nanoparticles for treatment of non-Hodgkin's lymphoma.

Overactivation of the PI3K/mTOR signaling has been identified in non-Hodgkin's lymphoma. BEZ235 is an effective dual PI3K/mTOR inhibitor, but it was withdrawn from early-phase clinical trials owing to poor solubility and on-target/off-tumor toxicity. Here, we developed a nanoparticle (NP)-based pretargeted system for the therapeutic delivery of BEZ235 to CD20- and HLA-DR-expressing lymphoma cells for targeted therapy. The pretargeted system is composed of dibenzocyclooctyne-functionalized anti-CD20 and anti-Lym1 antibodies as the tumor-targeting components and azide-functionalized BEZ235-encapsulated NPs as the effector drug carrier. Using lymphoma cell lines with different CD20 and HLA-DR antigen densities as examples, we demonstrate that the dual antibody pretargeted strategy effectively raises the number of NPs retained on the target tumor cells and improves the in vitro and in vivo antitumor activity of BEZ235 through the inhibition of the PI3K/mTOR pathway. Our data demonstrate that the NP-based pretargeted system improves the therapeutic window of small-molecule kinase inhibitor.

Outcomes for Relapsed and Refractory Peripheral T-Cell Lymphoma Patients after Front-Line Therapy from the COMPLETE Registry.

BACKGROUND: Outcomes for patients with peripheral T-cell lymphoma (PTCL) who fail to achieve complete response (CR) or relapse after front-line therapy are poor with lack of prospective outcomes data. OBJECTIVES: COMPLETE is a prospective registry of 499 patients enrolled at academic and community sites in the United States detailing patient demographics, treatment and outcomes for patients with aggressive T cell lymphomas. We report results for patients with primary refractory and relapsed disease. METHODS: Primary refractory disease was defined as an evaluable best response to initial treatment (induction ± maintenance or consolidation/transplant) other than CR, and included a partial response, progressive disease, or no response/stable disease. Relapsed disease was defined as an evaluable best response to initial treatment of CR, followed by disease progression at a later date, irrespective of time to progression. Patients were included in the analysis if initial treatment began within 30 days of enrollment and treatment duration was ≥4 days. RESULTS: Of 420 evaluable patients, 97 met the definition for primary refractory and 58 with relapsed disease. In the second-line setting, relapsed patients received single-agent therapies more often than refractory patients (52 vs. 28%; p = 0.01) and were more likely to receive single-agent regimens (74 vs. 53%; p = 0.03). The objective response rate to second-line therapy was higher in relapsed patients (61 vs. 40%; p = 0.04) as was the proportion achieving a CR (41 vs. 14%; p = 0.002). Further, relapsed patients had longer overall survival (OS) compared to refractory patients, with a median OS of 29.1 versus 12.3 months. CONCLUSIONS: Despite the availability of newer active single agents, refractory patients were less likely to receive these therapies and continue to have inferior outcomes compared to those with relapsed disease. PTCL in the real world remains an unmet medical need, and improvements in front-line therapies are needed.

Mogamulizumab: An Anti-CC Chemokine Receptor 4 Antibody for T-Cell Lymphomas.

Objective: To review the pharmacology, pharmacokinetics, efficacy, safety, dosing, and administration of mogamulizumab for the treatment of T-cell lymphomas. Data Sources: A literature search of PubMed (1966 to September 2019) was conducted using the keywords mogamulizumab, KW-0761, and lymphoma. Data were also obtained from package inserts and meeting abstracts. Study Selection and Data Extraction: All relevant published articles, package inserts, and unpublished meeting abstracts on mogamulizumab for the treatment of T-cell lymphomas were reviewed. Data Synthesis: Mogamulizumab is an anti-CC chemokine receptor 4 (CCR4) monoclonal antibody that has demonstrated activity in various T-cell lymphomas. It was approved by the US Food and Drug Administration (FDA) for the treatment of adult patients with relapsed or refractory mycosis fungoides (MF) or Sézary syndrome (SS) who have been treated with at least 1 prior line of therapy. Mogamulizumab demonstrated significant improvement in progression-free survival compared with vorinostat in patients with relapsed or refractory MF or SS. Serious adverse events associated with mogamulizumab include infusion-related reactions, cutaneous drug eruption, and autoimmune complications. Mogamulizumab administration in the preallogeneic hematopoietic stem cell transplant setting can increase the risk for severe posttransplant graft-versus-host disease. Relevance to Patient Care and Clinical Practice: Mogamulizumab is a first-in-class CCR4 inhibitor, providing a new option in the treatment of relapsed or refractory cutaneous T-cell lymphomas. Although not currently FDA approved for this indication, mogamulizumab may have some utility for the treatment of relapsed adult T-cell leukemia/lymphoma. Conclusion: The recent approval of mogamulizumab represents an important addition to the armamentarium of pharmacotherapies for T-cell lymphomas.

Inhibition of Aurora A Kinase in Combination with Chemotherapy Induces Synthetic Lethality and Overcomes Chemoresistance in Myc-Overexpressing Lymphoma.

BACKGROUND: Aberrant Myc expression plays a critical role in various tumors, including non-Hodgkin lymphoma (NHL). Myc-positive lymphoma is clinically aggressive, more resistant to chemotherapy, and associated with high mortality. OBJECTIVE: The current study aimed to show inhibition of aurora A kinase (AURKA) may overcome resistance to chemotherapy and improve outcomes in Myc-overexpressing lymphoma. METHODS: Myc-overexpressing lymphoma cell lines were evaluated by trypan blue, annexin V/propidium iodide staining, and western blotting for cytotoxicity, cell cycle, apoptosis, and Myc-associated protein expression, respectively, in the presence of cyclophosphamide with or without MLN8237, an AURKA inhibitor. Immunofluorescence for apoptosis-inducing factor (AIF) and acridine orange staining were used to analyze levels of autophagy. EµMyc genetically modified mouse model and xenograft models bearing Myc-overexpressing lymphoma cells were used to determine the efficacy of cyclophosphamide, MLN8237, or the combination in chemosensitive and chemoresistant tumors. RESULTS: In our in vitro experiments using chemoresistant lymphoma cells, MLN8237 and cyclophosphamide showed synergistic effects. Mice bearing lymphoma xenograft had rapid disease progression with median survival of ~ 35 days when treated with cyclophosphamide alone. In contrast, the combination of cyclophosphamide and MLN8237 induced complete tumor regression in all mice, which led to improvement in survival compared with the single agent control (p = 0.022). Kinome analysis of tumors treated with MLN8237 showed global suppression of various kinases. CONCLUSION: Our data demonstrate that AURKA inhibition induces synthetic lethality and overcomes chemoresistance in Myc-overexpressing lymphoma. The combination of MLN8237 and conventional chemotherapy showed promising safety and anti-tumor activities in preclinical models of Myc-positive NHL.