Huilai Zhang

Genetic heterogeneity in primary and relapsed mantle cell lymphomas: Impact of recurrent CARD11 mutations

The genetic mechanisms underlying disease progression, relapse and therapy resistance in mantle cell lymphoma (MCL) remain largely unknown. Whole-exome sequencing was performed in 27 MCL samples from 13 patients, representing the largest analyzed series of consecutive biopsies obtained at diagnosis and/or relapse for this type of lymphoma. Eighteen genes were found to be recurrently mutated in these samples, including known (ATM, MEF2B and MLL2) and novel mutation targets (S1PR1 and CARD11). CARD11, a scaffold protein required for B-cell receptor (BCR)-induced NF-κB activation, was subsequently screened in an additional 173 MCL samples and mutations were observed in 5.5% of cases. Based on in vitro cell line-based experiments, overexpression of CARD11 mutants were demonstrated to confer resistance to the BCR-inhibitor ibrutinib and NF-κB-inhibitor lenalidomide. Genetic alterations acquired in the relapse samples were found to be largely non-recurrent, in line with the branched evolutionary pattern of clonal evolution observed in most cases. In summary, this study highlights the genetic heterogeneity in MCL, in particular at relapse, and provides for the first time genetic evidence of BCR/NF-κB activation in a subset of MCL.

A Phase I Trial to Evaluate the Multiple-Dose Safety and Antitumor Activity of Ursolic Acid Liposomes in Subjects with Advanced Solid Tumors

Ursolic acid liposome (UAL), a new antitumor drug, has potential therapeutic value. However, limited clinical data exists regarding multiple-dose safety, antitumor activity, and the recommended dose (RD) of UAL for subjects with advanced solid tumors. All subjects were intravenously administered UAL for 14 consecutive days of a 21-day treatment cycle. Twenty-one subjects were enrolled in 1 of 3 sequential cohorts (56, 74, and 98 mg/m2) to evaluate multiple-dose tolerability and efficacy. Eight additional subjects were treated with UAL (74 mg/m2) to evaluate multiple-dose pharmacokinetics. No ≥grade 3 adverse events (NCI-CTC) were observed. Sixty percent subjects achieved stable disease after 2 treatment cycles. Multiple-dose pharmacokinetic analysis suggested UAL does not accumulate in the body. This trial demonstrates that UAL was tolerable, had manageable toxicity, and could potentially improve patient remission rates. A large phase II study is recommended to confirm these results (i.e., RD of 98 mg/m2).

Risk of second malignant neoplasms after cyclophosphamide-based chemotherapy with or without radiotherapy for non-Hodgkin lymphoma

Abstract Relatively little information is available on quantitative risks of therapy-induced second malignant neoplasm (SMN) in patients with non-Hodgkin lymphoma (NHL). A nested case–control study was conducted in a cohort of 3412 patients treated for NHL between 1990 and 2006, including 118 patients with SMN and 472 controls. Risks of leukemia/lung/breast/colorectal and bladder cancer were higher in NHL compared with the general population. A higher risk of leukemia was restricted to patients given a cumulative dose of cyclophosphamide more than 11 250 mg/m2. However, no significant association was found between SMN risk with rituximab, fludarabine, anthracyclines, epipodophyllotoxins and platinum, respectively. In combined modality treatment, involved-field radiation therapy (IFRT) had a higher risk for second solid cancers as compared to involved-nodal radiation therapy (INRT). For patients receiving radiation doses exceeding 40 Gy, the risk of lung cancer and breast cancer was increased. In conclusion, we found that cyclophosphamide-based therapy increased the risk of SMN in NHL. Leukemia risk was linked with high-dose cyclophosphamide. A received larger radiation field or higher radiation dose also could be an important risk factor for the development of SMN.

Co-expression of PD-L1 and p-AKT is associated with poor prognosis in diffuse large B-cell lymphoma via PD-1/PD-L1 axis activating intracellular AKT/mTOR pathway in tumor cells

Programmed death-1 (PD-1) /programmed death-ligand 1 (PD-L1) engagement usually leads to diminished antitumor T-cell responses, which mediates the immune escape of tumor cells. However, little is known whether PD-1/PD-L1 could directly activates intracellular oncogenic signaling pathways in tumor cells. The purpose of this study is to investigate whether intracellular AKT/mTOR signaling could be directly activated by PD-1/PD-L1 during the malignant progression in diffuse large B-cell lymphoma (DLBCL). Detection of the expression of PD-L1 and p-AKT by immunohistochemistry (IHC) showed that both proteins were overexpressed in 54% and 48% DLBCL cases, respectively. Spearman test showed that PD-L1 expression was correlated with p-AKT expression (R=0.244, χ2=5.962; P=0.017) and the expression of PD-L1 and p-AKT were also correlated with clinic-pathological characteristics. In addition, survival analysis showed that DLBCL patients who co-expressed PD-L1 and p-AKT had significantly poorer outcome than patients with single positive or both negative expression (P<0.05). In vitro, total PD-L1 and membrane PD-L1 (mPD-L1) proteins were overexpressed in five DLBCL cell lines by western blot and flow cytometry. We observed that AKT/mTOR pathway was activated in DLBCL cells after stimulated with human recombination PD-1/Fc. Taken together, these results suggested that the combination of PD-1/PD-L1 antibodies and AKT/mTOR inhibitor might be a promising and novel therapeutic approach for DLBCL in the future.

Low incidence of Epstein–Barr virus-positive diffuse large B-cell lymphoma of the elderly in Tianjin, northern China

Abstract The purpose of this study was to examine the incidence of Epstein–Barr virus (EBV)-positive diffuse large B-cell lymphoma of the elderly in a representative northern Chinese population. Overall, 212 cases of primary diffuse large B-cell lymphoma were analyzed for EBV-positive status by detection of EBV-encoded RNA using in situ hybridization. Immunophenotypic identity was verified by a streptavidin–biotin peroxidase detection system using the markers CD20, CD3, CD10, BCL6 and MUM1. The prevalence of EBV-positive diffuse large B-cell lymphoma in elderly northern Chinese patients was 3.8% (eight of 212). All eight cases were negative for CD10 and BCL6 immunostaining. The incidence is less frequent than that of southern China and other East-Asian countries. Patients tend to be older, present with a non-germinal center B-cell-like immunophenotype and have a poor outcome.

Inhibition of 4EBP phosphorylation mediates the cytotoxic effect of mechanistic target of rapamycin kinase inhibitors in aggressive B-cell lymphomas

Mechanistic target of rapamycin (mTOR) complex 1 is a central integrator of nutrient and growth factor inputs that controls cell growth in eukaryotes. The second generation of mTOR kinase inhibitors (TORKi), directly targeting the mTOR catalytic site, are more effective than rapamycin and its analogs in cancer treatment, particularly in inducing apoptosis. However, the mechanism underlying the cytotoxic effect of TORKi remains elusive. Herein, we demonstrate that TORKi-induced apoptosis is predominantly dependent on the loss of mTOR complex 1-mediated 4EBP activation. Knocking out RICTOR, a key component of mTOR complex 2, or inhibiting p70S6K has little effect on TORKi-induced apoptosis. Conversely, increasing the eIF4E:4EBP ratio by either overexpressing eIF4E or knocking out 4EBP1/2 protects lymphoma cells from TORKi-induced cytotoxicity. Furthermore, downregulation of MCL1 expression plays an important role in TORKi-induced apoptosis, whereas BCL-2 overexpression confers resistance to TORKi treatment. We further show that the therapeutic effect of TORKi in aggressive B-cell lymphomas can be predicted by BH3 profiling, and improved by combining it with pro-apoptotic drugs, especially BCL-2 inhibitors, both in vitro and in vivo. Taken together, the study herein provides mechanistic insight into TORKi cytotoxicity and identified a potential way to optimize its efficacy in the clinical treatment of aggressive B-cell lymphoma.

Upconverting and persistent luminescent nanocarriers for accurately imaging-guided photothermal therapy

The fluorescence-guided photothermal therapy (FPTT) has great potential in cancer treatment. However, the conventional FPTT has to be stimulated by external light, which tends to increase background noise and leads to the inaccurate infrared light irradiation for PTT. In this study, upconverting and persistent luminescent nanocarriers (UPLNs) loaded mesoporous silica nanoparticles (UPLNs@mSiO2) were first designed to solve the problem mentioned above. The UPLNs cores can effectively reduce the short-lived autofluorescence interference by exerting the delay time between signal acquisition and pulsed excitation light. For testing the luminescence properties, the indotcyanine green (ICG) as photothermal agent was encapsulated into the UPLNs@mSiO2. The experimental results showed that the UPLNs@mSiO2 nanoparticles could significantly reduce the short-lived autofluorescence interference and improve signal-to-noise ratio during FPTT. Our data suggest that UPLNs@mSiO2 may be a promising tool for improving the accuracy of PTT in vivo.

Synergistic antitumor effect of histone deacetylase inhibitor and Doxorubicin in peripheral T-cell lymphoma

Chidamide (CS055) is a new and highly selective histone deacetylase inhibitor displaying significant single-agent activity in peripheral T-cell lymphoma (PTCL). But there is little known the synergistic effect between CS055 and chemotherapy. The purpose of this study is to explore the synergistic effect and molecular mechanisms of CS055 combination with Doxorubicin in PTCL cells. We found that CS055 showed dose- and time-dependent inhibition effects on PTCL cell. Meanwhile, the synergistic effect was significantly observed after combination treatment with lower drug-concentration of CS055 and Doxorubicin. Lower drug-concentration of CS055 induced weak apoptosis in PTCL cells, but combination treatment with CS055 and Doxorubicin promoted more significant apoptosis. Combination treatment with CS055 and Doxorubicin significantly changed mitochondrial membrane potential and H3 acetylated level, resulting in up-regulating DNA damage protein p-γH2AX and apoptosis proteins including cleaved-caspase-3, cleaved-caspase-9 and cleaved-PARP, and down-regulating anti-apoptosis protein Bcl-2. In a word, Doxorubicin could increase the CS055-induced inhibition effects on PTCL cells, suggesting that CS055 combination with Doxorubicin or Doxorubicin-based chemotherapy drugs might be a new therapy approach for PTCL patients.

TPGS functionalized mesoporous silica nanoparticles for anticancer drug delivery to overcome multidrug resistance

Multidrug resistance (MDR) has become a very serious problem in cancer therapy. To effectively reverse MDR in tumor treatments, a new pH-sensitive nano drug delivery system (NDDS) composed of mesoporous silica nanoparticles (MSNs) and d-a-tocopheryl poly-ethylene glycol 1000 succinate (TPGS) copolymers was synthesized to deliver doxorubicin (DOX) into drug-resistant breast cancer cell line (MCF-7/ADR). DOX@MSNs-TPGS were characterized to have a single peak size distribution, high DOX loading efficiency and a pH-dependent drug release profile. MSNs-TPGS were internalized via caveolae, clathrin-mediated endocytosis and energy-dependent cellular uptake. The DOX@MSNs-TPGS exhibited 10-fold enhanced cell killing potency compared to free DOX and DOX@MSNs. The enhanced MDR reversal effect was ascribed to the higher amount of cellular uptake of DOX@MSNs-TPGS in MCF-7/ADR cells than that of free DOX and DOX@MSNs, as a result of the inhibition of P-gp mediated drug efflux by TPGS. In vivo studies of NDDS in tumor-bearing mice showed that DOX@MSNs-TPGS displayed better efficacy against MDR tumors in mice and reached the tumor site more effectively than DOX and DOX@MSNs, with minimal toxicity. These results suggest DOX@MSNs-TPGS developed in this study have promising applications to overcome drug resistance in tumor treatments.

Necroptosis as a potential therapeutic target in multiple organ dysfunction syndrome

Purpose To investigate how necroptosisis, i.e. programmed necrosis, is involved in MODS, and to examine whether Nec-1, a specific necroptosis inhibitor, ameliorates multiorgan injury in MODS. Experimental Design A model of MODS was established in six-week old SD rats using fracture trauma followed by hemorrhage. Control animals received sham surgery. Cell death form and necrosome formation were measured by fluorescence-activated cell sorting and western blotting. MODS rats were randomly assigned to receive Nec-1 or saline with pretreatment and once daily. The first end-point was 72 hours survival. Organ injury and dysfunction, inflammatory cytokine levels, and necroptotic execution protein expression were also recorded. Results Organ injury and dysfunction were significantly more severe in the MODS group than the sham group (all p<0.01). Furthermore, MODS-induced liver, lung and kidney tissue injury was characterized by necroptosis rather than apoptosis, and accompanied by necrosome formation. Compared to MODS group, Nec-1 administration significantly improved 72 hours survival (p<0.01). Nec-1 administration significantly reduced necroptosis-induced liver, lung and kidney injury and dysfunction, inhibited inflammatory cytokines production, inhibited release of necroptotic execution proteins such as high-mobility group box 1 and mixed-lineage kinase domain-like protein pseudokinase in MODS rats (all p<0.01). Conclusions These results suggest that necroptosis is involved the pathology of MODS. Further, a necroptotic inhibitor Nec-1 may be considered as an adjunct treatment for MODS.PURPOSE To investigate how necroptosisis, i.e. programmed necrosis, is involved in MODS, and to examine whether Nec-1, a specific necroptosis inhibitor, ameliorates multiorgan injury in MODS. EXPERIMENTAL DESIGN A model of MODS was established in six-week old SD rats using fracture trauma followed by hemorrhage. Control animals received sham surgery. Cell death form and necrosome formation were measured by fluorescence-activated cell sorting and western blotting. MODS rats were randomly assigned to receive Nec-1 or saline with pretreatment and once daily. The first end-point was 72 hours survival. Organ injury and dysfunction, inflammatory cytokine levels, and necroptotic execution protein expression were also recorded. RESULTS Organ injury and dysfunction were significantly more severe in the MODS group than the sham group (all p<0.01). Furthermore, MODS-induced liver, lung and kidney tissue injury was characterized by necroptosis rather than apoptosis, and accompanied by necrosome formation. Compared to MODS group, Nec-1 administration significantly improved 72 hours survival (p<0.01). Nec-1 administration significantly reduced necroptosis-induced liver, lung and kidney injury and dysfunction, inhibited inflammatory cytokines production, inhibited release of necroptotic execution proteins such as high-mobility group box 1 and mixed-lineage kinase domain-like protein pseudokinase in MODS rats (all p<0.01). CONCLUSIONS These results suggest that necroptosis is involved the pathology of MODS. Further, a necroptotic inhibitor Nec-1 may be considered as an adjunct treatment for MODS.