Evaluation safety and efficacy of immune checkpoint blockers (ICB) and radiotherapy combination versus ICB in non-small cell lung cancer patients with recurrence or metastasis: A systematic review and meta-analysis.

BACKGROUND: Currently, immune checkpoint blockers (ICB) and radiotherapy (RT) combination therapy is broadly applied in non-small cell lung cancer (NSCLC) patients. However, meta-analysis about safety and efficacy of RT + ICB versus ICB has not yet been reported. To evaluate safety and efficacy of the combination therapy of ICB and RT in patients with recurrent or metastatic NSCLC and explore factors related to higher response rates, longer lifetime, and lower toxicity, meta-analysis of previous clinical data will be presented in this article. METHODS: A literature search on patients with recurrent or metastatic NSCLC treated with RT + ICB versus ICB was performed using the Cochrane Library, Embase and PubMed up to December 10, 2022. Suitable quality assessment checklists were selected corresponding to various types of research studies. Comparative and single-arm studies were analyzed using Stata 14.0. RESULTS: 10 comparative studies and 15 arms of combination therapy were included for this meta-analysis. RT significantly improved objective response rate (ORR), disease control rate (DCR), and overall survival (OS) and progression-free survival (PFS) of ICB (I-square value (I2 ) = 0.00%, odds ratio (OR) 1.28, 95% confidence interval (CI) 1.09-1.49, I2 = 0.00%, OR 1.12, 95% CI 1.00-1.25, I2 = 42.1%, OR 0.81, 95% CI 0.72-0.92, I2 = 34.5%, OR 0.80, and 95% CI 0.71-0.89, respectively). Toxicity between combination therapy and ICB monotherapy did not significantly differ in any grade or in ≥3 grade of tr-AEs (I2 = 0.00%, OR 1.05, 95% CI 0.91-1.22, I2 = 0.00%, OR 1.46, 95% CI 0.90-2.37, respectively). Subgroup analyses based on single-arm studies showed that applications of SRS/SBRT, PD-1 inhibitor, and administration of ICB after RT were conducive to a better DCR, longer OS and mild adverse events (heterogeneity between groups (HBG) all p < 0.05). CONCLUSION: RT can significantly improve ORR, DCR, OS, and PFS of ICB in patients with recurrent or metastatic NSCLC without increasing toxicity. PD-1 inhibitor following SRS/SBRT could be the best option to maximally benefit the patients.

Early changes in soluble intracellular adhesion molecule-1 as prognostic biomarkers to immune checkpoint inhibitor.

Serologic biomarker to predict clinical outcome is needed for immune checkpoint inhibitors (ICIs). We evaluated soluble intercellular adhesion molecules-1 (sICAM-1) as a predictor of response to ICIs treatment. Ninety-five patients with cancer treated with ICI were studied. The serum sICAM-1 levels of baseline, post two cycle therapy and end of therapy (EOT) were measured by enzyme-linked immunoassay. We randomly assigned the patients into the primary cohort (n = 47) and validation cohort (n = 48). Serum sICAM-1 post two cycle (277.7 ± 181.6 ng/mL) and EOT (403.9 ± 218.9 ng/mL) were significantly elevated compared to baseline (244.8 ± 153.8 ng/mL, p = 0.008 and p = 0.004, respectively). Early changes of sICAM-1 (ΔsICAM-1), deemed as sICAM-1 after two cycles minus baseline, were assessed. Following ICI treatments, responders had significantly lower ΔsICAM-1 compared with nonresponders in the primary cohort (p = 0.040) and the validation cohort (p = 0.026). High ΔsICAM-1 was strongly associated with inferior progression-free survival (PFS; (primary cohort: p = 0.001 and validation cohort: p = 0.002) and overall survival (OS; (primary cohort: p < 0.001 and validation cohort: p = 0.007). The ΔsICAM-1 remained independently associated with worse PFS and OS in the primary cohort and the validation cohort. Subgroup analysis indicated patients whose sICAM-1 significantly elevated had shorter PFS and OS in both anti-PD-1 and anti-PD-L1 treatment groups. Early change of serum sICAM-1 could be used to monitor and predict clinical benefit of ICI therapy in patients with solid cancer.

Early Changes of Serum Interleukin 14α Levels Predicts the Response to Anti-PD-1 Therapy in Cancer.

Background: Programmed cell death-1 (PD-1) blockade has been shown to confer clinical benefit in cancer patients. Here, we assessed the level of serum interleukin 14α (IL14α) in patients receiving anti-PD-1 treatment. Methods: This prospective study recruited 30 patients with advanced solid cancer who received pembrolizumab treatment in Northern Jiangsu People's Hospital between April 2016 and June 2018. The western blot analysis was used to assess the expression level of serum IL14α in patients at baseline and after 2 cycles of treatment. Interleukin 14α was performed using the unpaired 2-tailed Student test. The progression-free survival (PFS) and overall survival (OS) were calculated using the Kaplan-Meier method and compared by the log-rank test. Results: The early change of IL14α after 2 cycles of anti-PD-1 therapy was calculated as delta IL14α % change = (IL14α level after 2 cycles - IL14α level before treatment)/IL14α level before treatment × 100%. Receiver operating characteristic (ROC) was analyzed to get a cutoff point of delta IL14α % change as 2.46% (sensitivity = 85.71%, specificity = 62.5%; area under the ROC curve [AUC] = 0.7277, P = .034). Using this cutoff to subgroup the patients, an improved objective response rate was observed in patients with a delta IL14α change higher than 2.46% (P = .0072). A delta IL14α change over 2.46% was associated with a superior PFS (P = .0039). Conclusions: Early changes of serum IL14α levels may be a promising biomarker to predict outcomes in patients with solid cancer following anti-PD-1 treatment.

Inhibition of USP1 reverses the chemotherapy resistance through destabilization of MAX in the relapsed/refractory B-cell lymphoma.

The patients with relapsed and refractory diffuse large B-cell lymphoma (DLBCL) have poor prognosis, and a novel and effective therapeutic strategy for these patients is urgently needed. Although ubiquitin-specific protease 1 (USP1) plays a key role in cancer, the carcinogenic effect of USP1 in B-cell lymphoma remains elusive. Here we found that USP1 is highly expressed in DLBCL patients, and high expression of USP1 predicts poor prognosis. Knocking down USP1 or a specific inhibitor of USP1, pimozide, induced cell growth inhibition, cell cycle arrest and autophagy in DLBCL cells. Targeting USP1 by shRNA or pimozide significantly reduced tumor burden of a mouse model established with engraftment of rituximab/chemotherapy resistant DLBCL cells. Pimozide significantly retarded the growth of lymphoma in a DLBCL patient-derived xenograft (PDX) model. USP1 directly interacted with MAX, a MYC binding protein, and maintained the stability of MAX through deubiquitination, which promoted the transcription of MYC target genes. Moreover, pimozide showed a synergetic effect with etoposide, a chemotherapy drug, in cell and mouse models of rituximab/chemotherapy resistant DLBCL. Our study highlights the critical role of USP1 in the rituximab/chemotherapy resistance of DLBCL through deubiquitylating MAX, and provides a novel therapeutic strategy for rituximab/chemotherapy resistant DLBCL.

Prevalence of Myositis-Specific Autoantibodies and Myositis-Associated Autoantibodies in COVID-19 Patients: A Pilot Study and Literature Review.

Coronavirus disease 2019 (COVID-19) infection has been linked to numerous autoimmune manifestations. Neither the mechanism nor the etiology of this association has been fully explored or elucidated. Prior studies have detected myositis in patients with proven COVID-19 infection, suggesting a relationship between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and the development of myositis. Studies have reported elevated levels of autoimmune antibodies, including myositis-specific autoantibodies (MSAs) and myositis-associated autoantibodies (MAAs), in patients with COVID-19 infection, however the prevalence is not well documented. Our objective was to assess the prevalence of MSAs and MAAs in COVID-19 patients compared with unaffected subjects. Serum samples from 74 unvaccinated, polymerase chain reaction (PCR)-positive COVID-19 infected patients were compared with serum samples from 41 healthy, unaffected individuals. All serum samples were tested for MSA and MAA reactivity. Within the COVID-19-positive group, six (8.1%) patients exhibited MSA/MAA positivity, compared with only one (2.4%) individual from the control group. Although a higher prevalence of MSA/MAA positivity was observed within the COVID-19 infected group, the difference did not reach statistical significance (p=0.223). The autoantibodies detected in this study have a unique association with dermatomyositis and other inflammatory myopathies, and may play a role in COVID-19-associated myopathy. This article was previously presented as an abstract at Jacobs School of Medicine and Biomedical Sciences Research Day on June 3rd, 2022.

Hexokinase II expression as a prognostic marker in diffuse large B-cell lymphoma: pre- and post-rituximab era.

We aimed to assess HKII expression and its prognostic significance in diffuse large B-cell lymphoma (DLBCL) patients. The HKII protein level was determined by immunohistochemistry in 159 newly diagnosed DLBCL patients, and its relationship with overall response rate, progression-free survival (PFS), and overall survival (OS) was analyzed. HKII was expressed in 95 DLBCL patients (59.7%). HKII-positive patients had poorer outcomes than negative patients for 5-y PFS (68% vs. 84%, p = 0.029) and 5-y OS (78% vs. 94%, p = 0.05). When only patients without no bulky disease, B symptoms, or extranodal involvement who had low IPI scores were considered, those with positive HKII had worse 5y-PFS and 5y-OS (p < 0.05). Multivariate analysis indicated that HKII status was an independent prognostic factor of OS. In subgroup analysis, HKII expression was associated with inferior OS in the CHOP group (p = 0.017). In CHOP group patients without bulky disease or extranodal involvement who had low LDH and low IPI scores (p < 0.05), positive HKII was associated with worse PFS and OS. No differences in PFS and OS, or any independent prognostic factors, were found in the RCHOP group. In DLBCL, HKII is valuable as a prognostic biomarker and may be useful as a tool for assessing disease risk.

Four cycles of R-CHOP followed by two applications of rituximab based on negative interim PET/CT: an analysis of a prospective trial.

BACKGROUND: R-CHOP with or without radiotherapy is the standard treatment for limited-stage diffuse large B-cell lymphoma (DLBCL). To prevent overtreatment, we assessed whether four cycles of CHOP plus six applications of rituximab was adequate with negative interim PET/CT and the role of consolidation radiotherapy specifically for patients with Waldeyer's ring DLBCL. One hundred and twenty-nine patients with limited-stage DLBCL were enrolled in this open-label, nonrandomized, single-arm, phase 2 clinical trial (NCT01804127). METHODS: All patients were initially treated with 4 cycles of R-CHOP and underwent interim PET/CT. Patients with negative PET/CT (Deauville scores 1-2) received 2 additional cycles of rituximab monotherapy, unless they had any risk factors (primary mediastinal large B-cell lymphoma, extranodal primary or bulky disease). Otherwise, patients received another 2 cycles of R-CHOP. Patients with partial response on interim PET/CT received another 4 cycles of R-CHOP. No radiotherapy was conducted in Waldeyer's ring DLBCL patients with negative PET/CT. The primary endpoint was 3-year progression-free survival (PFS). Overall survival (OS) in this study was compared with those from a historical study (NCT 00854568159). RESULTS: One hundred fifteen interim PET/CT scans (89.1%) were negative after 4 cycles of R-CHOP. An elevated lactate dehydrogenase level was significantly associated with positive interim PET/CT (P < 0.05). A trend of inferior outcome was observed in patients with positive interim PET/CT in terms of 3-year PFS (78.6% vs. 91.9%, P = 0.24) and 3-year OS (85.7% vs. 95.6%, P = 0.16). There were no PFS or OS differences found between patients treated with 4R-CHOP+2R and those treated with 6R-CHOP from a historical control study. Patients with Waldeyer's ring DLBCL and negative interim PET/CT achieved a 3-year PFS of 87.2% and a 3-year OS of 89.7%. CONCLUSIONS: Our results suggested that for interim PET/CT-negative patients without risk factors, the extra 2 cycles of CHOP might be omitted, and radiotherapy might also be omitted in patients with Waldeyer's ring DLBCL without compromising the efficacy. These results need to be confirmed in a randomized study. TRIAL REGISTRATION: clinicaltrials.gov , NCT01804127 . Date of first registration: 05/03/2013.

Deubiquitinase OTUD7B is a potential prognostic biomarker in diffuse large B-cell lymphoma.

OTUD7B is a deubiquitinase and has been reported as a prognostic factor in various solid tumors. However, its prognostic value in lymphoma patients remains unclear. We detected OTUD7B expression levels in 160 diffuse large B-cell lymphoma (DLBCL) tissue samples by immunohistochemistry, and analyzed correlations between its expression and clinic-pathologic parameters as well as clinical outcomes. We also investigated association between OTUD7B expression and chemotherapeutic drugs anti-tumor activity in vitro. We found that OTUD7B overexpressed in 129 (80.6%) cases, and patients with overexpression of OTUD7B experienced better overall survival comparing to those with OTUD7B low expression (P=0.021). Multivariate Cox regression analysis illustrated that OTUD7B was an independent prognostic indicator. In DLBCL cell lines, we found that Chidamide could up-regulate OTUD7B in several DLBCL cell lines, and also had synergistic effect with doxorubicin at low concentration. Our data illustrated that OTUD7B deficiency is a negative predictor of clinical outcome, and might be a potential therapeutic target in the treatment of diffuse large B-cell lymphoma.

Chidamide triggers BTG1-mediated autophagy and reverses the chemotherapy resistance in the relapsed/refractory B-cell lymphoma.

Rituximab/chemotherapy relapsed and refractory B cell lymphoma patients have a poor overall prognosis, and it is urgent to develop novel drugs for improving the therapy outcomes. Here, we examined the therapeutic effects of chidamide, a new histone deacetylase (HDAC) inhibitor, on the cell and mouse models of rituximab/chemotherapy resistant B-cell lymphoma. In Raji-4RH/RL-4RH cells, the rituximab/chemotherapy resistant B-cell lymphoma cell lines (RRCL), chidamide treatment induced growth inhibition and G0/G1 cell cycle arrest. The primary B-cell lymphoma cells from Rituximab/chemotherapy relapsed patients were sensitive to chidamide. Interestingly, chidamide triggered the cell death with the activation of autophagy in RRCLs, likely due to the lack of the pro-apoptotic proteins. Based on the RNA-seq and chromatin immunoprecipitation (ChIP) analysis, we identified BTG1 and FOXO1 as chidamide target genes, which control the autophagy and the cell cycle, respectively. Moreover, the combination of chidamide with the chemotherapy drug cisplatin increased growth inhibition on the RRCL in a synergistic manner, and significantly reduced the tumor burden of a mouse lymphoma model established with engraftment of RRCL. Taken together, these results provide a theoretic and mechanistic basis for further evaluation of the chidamide-based treatment in rituximab/chemotherapy relapsed and refractory B-cell lymphoma patients.

The adhesion molecule ICAM-1 in diffuse large B-cell lymphoma post-rituximab era: relationship with prognostic importance and rituximab resistance.

Intercellular adhesion molecule-1 (ICAM-1) is a cell-surface receptor contributing to lymphocyte homing, adhesion and activation. The prognostic significance of the protein is unknown in diffuse large B-cell lymphoma (DLBCL) in post-rituximab era. We detected expression of ICAM-1 immunohistochemically in 102 DLBCL tissue samples. Overexpression of ICAM-1 was found in 28 (27.5%) cases. In patients with low ICAM-1 expression levels, the addition of rituximab to CHOP (cyclophosphamide, doxorubicin, vincristine and prednisone) chemotherapy resulted in an improved overall response rate, progression-free survival (PFS) and overall survival (OS) (P=0.019, 0.01, 0.02). In pre-clinical models, we found that chronic exposure of cell lines to rituximab led to downregulation of ICAM-1 and acquirement of a rituximab resistant phenotype. In vitro exposure of rituximab resulted in rapid aggregation of B-cells regardless of the ICAM-1 expression levels. MTT assay showed knockdown of ICAM-1 could cause rituximab resistance. Neutralization of ICAM-1 did not affect rituximab activity in vitro and in vivo. Our data illustrated that in post-rituximab era, R-CHOP significantly improved the ORR, PFS and OS in ICAM-1 negative subset patients. Downregulation of ICAM-1 may contribute to rituximab resistance, and that rituximab, by promoting cell-cell aggregation, may sensitize cells to the cytotoxic effects of chemotherapy agents.

Metformin sensitizes therapeutic agents and improves outcome in pre-clinical and clinical diffuse large B-cell lymphoma.

BACKGROUND: The treatment of diffuse large B-cell lymphoma (DLBCL) is limited by the development of resistance to therapy, and there is a need to develop novel therapeutic strategies for relapsed and refractory aggressive lymphoma. Metformin is an oral agent for type 2 diabetes that has been shown to decrease cancer risk and lower mortality in other types of cancer. METHODS: We performed a retrospective analysis of the RPCCC database looking at patients with DLBCL treated with front-line chemotherapy. We also performed pre-clinical studies looking at the effect of metformin on cell viability, cell number, Ki67, ATP production, apoptosis, ROS production, mitochondrial membrane potential, cell cycle, effect with chemotherapeutic agents, and rituximab. Finally, we studied mouse models to see the anti-tumor effect of metformin. RESULTS: Among diabetic patients, metformin use was associated with improved progression-free survival (PFS) and overall survival (OS) compared to diabetic patients not on metformin. Our pre-clinical studies showed metformin is itself capable of anti-tumor effects and causes cell cycle arrest in the G1 phase. Metformin induces apoptosis, ROS production, and increased mitochondrial membrane permeability. Metformin exhibited additive/synergistic effects when combined with traditional chemotherapy or rituximab in vitro. In vivo, metformin in combination with rituximab showed improved survival compared with rituximab monotherapy. CONCLUSIONS: Our retrospective analysis showed that metformin with front-line chemotherapy in diabetic patients resulted in improved PFS and OS. Our pre-clinical studies demonstrate metformin has potential to re-sensitize resistant lymphoma to the chemo-immunotherapy and allow us to develop a hypothesis as to its activity in DLBCL.

The SMAC mimetic LCL-161 displays antitumor activity in preclinical models of rituximab-resistant B-cell lymphoma.

Clinical observations suggest the existence of shared resistance pathways between rituximab and chemotherapy agents. To explore the mechanisms of rituximab resistance, our group created rituximab-resistant cell lines (RRCLs), which display altered expression of several inhibitor of apoptosis (IAP) family proteins. Here, we provide evidence to support pharmacologically targeting IAPs in lymphoma with LCL-161, a small molecule mimetic of the second mitochondria-derived activator of caspases (SMAC). The antitumor effect of LCL-161 was determined using luminescent adenosine triphosphate assays, flow cytometry, SCID mouse xenografts, and ex vivo patient biopsy sample studies. In vitro exposure to LCL-161 also resulted in a dose-dependent decrease in IAP levels, along with synergistic enhancement of the antitumor effect of cytotoxic chemotherapy, in rituximab-sensitive cell lines and RRCLs. In addition, LCL-161 increased the cytotoxic effect of the proteasome inhibitor carfilzomib in ex vivo lymphoma patient samples. The combination of LCL-161 with the chemotherapy regimen rituximab, gemcitabine, and vinorelbine (RGV) improved in vivo survival compared with RGV alone in severe combined immunodeficient mice implanted with RRCLs but not in animals implanted with rituximab-sensitive cell lines. In summary, LCL-161 exhibits synergistic antitumor activity in both in vitro and in vivo models of resistant lymphoma. Our data support further preclinical investigation of LCL-161 as a novel antilymphoma agent.

Up-regulation of hexokinase II contributes to rituximab-chemotherapy resistance and is a clinically relevant target for therapeutic development.

In order to identify cellular pathways associated with therapy-resistant aggressive lymphoma, we generated rituximab-resistant cell lines (RRCL) and found that the acquirement of rituximab resistance was associated with a deregulation in glucose metabolism and an increase in the apoptotic threshold leading to chemotherapy resistance. Hexokinase II (HKII), the predominant isoform overexpressed in cancer cells, has dual functions of promoting glycolysis as well as inhibiting mitochondrial-mediated apoptosis. We found that RRCL demonstrated higher HKII levels. Targeting HKII resulted in decreased mitochondrial membrane potential, ATP production, cell viability; and re-sensitization to chemotherapy agents. Analyzed gene expression profiling data from diffuse large B-cell lymphoma patients, high-HKII levels were associated with a shorter progression free survival (PFS) and/or overall survival (OS). Our data suggest that over-expression of HKII is associated with resistance to rituximab and chemotherapy agents in aggressive lymphoma and identifies this enzyme isoform as a potential therapeutic target.

Development and Testing of an Intelligent Pain Management System (IPMS) on Mobile Phones Through a Randomized Trial Among Chinese Cancer Patients: A New Approach in Cancer Pain Management.

BACKGROUND: Cancer has become increasingly prevalent in China over the past few decades. Among the factors that determine the quality of life of cancer patients, pain has commonly been recognized as a most critical one; it could also lead to the ineffective treatment of the cancer. Driven by the need for better pain management for cancer patients, our research team developed a mobile-based Intelligent Pain Management System (IPMS). OBJECTIVE: Our objective was to design, develop, and test the IPMS to facilitate real-time pain recording and timely intervention among cancer patients with pain. The system's usability, feasibility, compliance, and satisfaction were also assessed. METHODS: A sample of 46 patients with cancer pain symptoms were recruited at the Oncology Center of Xinhua Hospital affiliated to Shanghai Jiao Tong University School of Medicine, Chongming Branch (hereinafter referred to as "the Oncology Center"). In a pretest, participants completed a pain management knowledge questionnaire and were evaluated using the baseline cancer pain assessment and Karnofsky Performance Status (KPS) evaluation. The participants were then randomly assigned into two groups (the trial group and the control group). After a 14-day trial period, another round of cancer pain assessment, KPS evaluation and pain management knowledge assessment were repeated. In the trial group, the data were fully automatically collected by the IPMS. In the control group, the data were collected using conventional methods, such as phone interviews or door-to-door visits by physicians. The participants were also asked to complete a satisfaction questionnaire on the use of the IPMS. RESULTS: All participants successfully completed the trial. First, the feasibility of IPMS by observing the number of daily pain assessments recorded among patients was assessed. Second, the users' satisfaction, effectiveness of pain management, and changes in the quality of their lives were evaluated. All the participants gave high satisfaction score after they used IMPS. Both groups reported similar pain scores and KPS scores at the baseline. At the end of the trial, the mean pain score of the trial group was significantly lower than of the control group (P<.001). The ending KPS score of the trial group was significantly higher than of the control group (P<.001). The improvement of pain management knowledge score in the trial group was more pronounced than that in the control group (P<.001). CONCLUSIONS: This study provided preliminary data to support the potentials of using IPMS in cancer pain communication between patients and doctors and to provide real-time supportive intervention on a convenient basis at a low cost. Overall, the IPMS can serve as a reliable and effective approach to control cancer pain and improve quality of life for patients with cancer pain. TRIAL REGISTRATION: Clinicaltrials.gov NCT02765269; http://clinicaltrials.gov/ct2/show/NCT02765269 (Archived by WebCite at http://www.webcitation.org/6rnwsgDgv).

Mitotic catastrophe and cell cycle arrest are alternative cell death pathways executed by bortezomib in rituximab resistant B-cell lymphoma cells.

The ubiqutin-proteasome system (UPS) plays a role in rituximab-chemotherapy resistance and bortezomib (BTZ) possesses caspase-dependent (i.e. Bak stabilization) and a less characterized caspase-independent mechanism-of-action(s). Here, we define BTZ-induced caspase-independent cell death pathways. A panel of rituximab-sensitive (RSCL), rituximab-resistant cell lines (RRCL) and primary tumor cells derived from lymphoma patients (N = 13) were exposed to BTZ. Changes in cell viability, cell-cycle, senescence, and mitotic index were quantified. In resting conditions, RRCL exhibits a low-proliferation rate, accumulation of cells in S-phase and senescence. Exposure of RRCL to BTZ reduces cell senescence, induced G2-M phase cell-cycle arrest, and is associated with mitotic catastrophe. BTZ stabilized p21, CDC2, and cyclin B in RRCL and in primary tumor cells. Transient p21 knockdown alleviates BTZ-induced senescence inhibition, G2-M cell cycle blockade, and mitotic catastrophe. Our data suggest that BTZ can induce apoptosis or mitotic catastrophe and that p21 has a pivotal role in BTZ activity against RRCL.

Cardiotoxicity as indicated by LVEF and troponin T sensitivity following two anthracycline-based regimens in lymphoma: Results from a randomized prospective clinical trial.

Anthracycline-induced cardiotoxicity influences treatment selection and may negatively affect clinical outcomes in lymphoma patients. While epirubicin induced cardiotoxicity less often than the same dose of doxorubicin in breast cancer, higher doses of epirubicin are required in lymphoma regimens for equivalent efficacy. Whether a higher dosage of epirubicin also induces cardiotoxicity less often than doxorubicin in lymphoma remains unknown. We therefore administered 6-8 cycles of cyclophosphamide, vincristine and prednisone (CEpOP) +/- rituximab (R) with either epirubicin (CEpOP) or doxorubicin (CHOP) to patients (N=398) with untreated diffuse large B-cell lymphoma (DLBCL) or follicular lymphoma grade 3 (FLG3). Left ventricular ejection fraction (LVEF) and high-sensitivity serum cardiac troponin T (HsTnT) were assessed at baseline and after 4 cycles of treatment. Epirubicin (70 mg/m2/dose) was equivalent to doxorubicin (50 mg/m2/dose) in terms of 3-year progression-free survival. The risk of decreased LVEF was similar between the two regimens. CEpOP+/-R induced HsTnT elevation less often than CHOP+/-R. We conclude that CEpOP+/-R is a more acceptable regimen with short-term efficacy similar to CHOP+/-R in lymphoma patients. Longer follow-up is needed to monitor the risk of cardiac dysfunction and determine whether differences in the induction of elevated HsTnT between epirubicin and doxorubicin justify changes in clinical practice.

Vorinostat, a histone deacetylase (HDAC) inhibitor, promotes cell cycle arrest and re-sensitizes rituximab- and chemo-resistant lymphoma cells to chemotherapy agents.

PURPOSE: Preclinical models of chemotherapy resistance and clinical observations derived from the prospective multicenter phase III collaborative trial in relapsed aggressive lymphoma (CORAL) study demonstrated that primary refractory/relapsed B cell diffuse large B cell lymphoma has a poor clinical outcome with current available second-line treatments. Preclinically, we found that rituximab resistance is associated with a deregulation on the mitochondrial potential rendering lymphoma cells resistant to chemotherapy-induced apoptotic stimuli. There is a dire need to develop agents capable to execute alternative pathways of cell death in an attempt to overcome chemotherapy resistance. Posttranscriptional histone modification plays an important role in regulating gene transcription and is altered by histone acetyltransferases (HATs) and histone deacetylases (HDACs). HDACs regulate several key cellular functions, including cell proliferation, cell cycle, apoptosis, angiogenesis, migration, antigen presentation, and/or immune regulation. Given their influence in multiple regulatory pathways, HDAC inhibition is an attractive strategy to evaluate its anti-proliferation activity in cancer cells. To this end, we studied the anti-proliferation activity and mechanisms of action of suberoylanilide hydroxamic acid (SAHA, vorinostat) in rituximab-chemotherapy-resistant preclinical models. METHODS: A panel of rituximab-chemotherapy-sensitive (RSCL) and rituximab-chemotherapy-resistant cell lines (RRCL) and primary tumor cells isolated from relapsed/refractory B cell lymphoma patients were exposed to escalating doses of vorinostat. Changes in mitochondrial potential, ATP synthesis, and cell cycle distribution were determined by Alamar blue reduction, Titer-Glo luminescent assays, and flow cytometric, respectively. Protein lysates were isolated from vorinostat-exposed cells, and changes in members of Bcl-2 family, cell cycle regulatory proteins, and the acetylation status of histone H3 were evaluated by Western blotting. Finally, cell lines were pre-exposed to vorinostat for 48 h and subsequently exposed to several chemotherapy agents (cisplatin, etoposide, or gemcitabine); changes in cell viability were determined by CellTiter-Glo(®) luminescence assay (Promega, Fitchburg, WI), and synergistic activity was evaluated using the CalcuSyn software. RESULTS: Vorinostat induced dose-dependent cell death in RRCL and in primary tumor cells. In addition, in vitro exposure of RRCL to vorinostat resulted in an increase in p21 and acetylation of histone H3 leading to G1 cell cycle arrest. Vorinostat exposure resulted in apoptosis in RSCL cell lines but not in RRCL. This finding suggests that in RRCL, vorinostat induces cell death by alternative pathways (i.e., irreversible cell cycle arrest). Of interest, vorinostat was found to reverse acquired chemotherapy resistance in RRCL. CONCLUSIONS: Our data suggest that vorinostat is active in RRCL with a known defective apoptotic machinery, it can active alternative cell death pathways. Given the multiple pathways affected by HDAC inhibition, vorinostat can potentially be used to overcome acquired resistant to chemotherapy in aggressive B cell lymphoma.

Entinostat, a novel histone deacetylase inhibitor is active in B-cell lymphoma and enhances the anti-tumour activity of rituximab and chemotherapy agents.

Histone deacetylases (HDACs) inhibitors are active in T-cell lymphoma and are undergoing pre-clinical and clinical testing in other neoplasms. Entinostat is an orally bioavailable class I HDAC inhibitor with a long half-life, which is under evaluation in haematological and solid tumour malignancies. To define the activity and biological effects of entinostat in B-cell lymphoma we studied its anti-tumour activity in several rituximab-sensitive or -resistant pre-clinical models. We demonstrated that entinostat is active in rituximab-sensitive cell lines (RSCL), rituximab-resistant cell lines (RRCL) and primary tumour cells isolated from lymphoma patients (n = 36). Entinostat exposure decreased Bcl-XL (BCL2L1) levels and induced apoptosis in cells. In RSCL and RRCL, entinostat induced p21 (CDKN1A) expression leading to G1 cell cycle arrest and exhibited additive effects when combined with bortezomib or cytarabine. Caspase inhibition diminished entinostat activity in some primary tumour cells suggesting that entinostat has dual mechanisms-of-action. In addition, entinostat increased the expression of CD20 and adhesion molecules. Perhaps related to these effects, we observed a synergistic activity between entinostat and rituximab in a lymphoma-bearing severe combined immunodeficiency (SCID) mouse model. Our data suggests that entinostat is an active HDAC inhibitor that potentiates rituximab activity in vivo and supports its further clinical development in B-cell lymphoma.