In vitro induction of apoptosis for nasal angiocentric natural killer cell lymphoma-derived cell line, NK-YS, by etoposide and cyclosporine A

Therapeutic challenges in peripheral T-cell lymphoma

Peripheral T-cell lymphoma (PTCL) is a rare and heterogeneous group of hematological malignancies. Compared to our knowledge of B-cell tumors, our understanding of T-cell leukemia and lymphoma remains less advanced, and a significant number of patients are diagnosed with advanced stages of the disease. Unfortunately, the development of drug resistance in tumors leads to relapsed or refractory peripheral T-Cell Lymphomas (r/r PTCL), resulting in highly unsatisfactory treatment outcomes for these patients. This review provides an overview of potential mechanisms contributing to PTCL treatment resistance, encompassing aspects such as tumor heterogeneity, tumor microenvironment, and abnormal signaling pathways in PTCL development. The existing drugs aimed at overcoming PTCL resistance and their potential resistance mechanisms are also discussed. Furthermore, a summary of ongoing clinical trials related to PTCL is presented, with the aim of aiding clinicians in making informed treatment decisions.

Extranodal NK/T Cell Lymphoma: Evidence-based Review of Safety and Toxicity of the Available Regimens

Extranodal natural killer/T cell lymphoma (ENKTL) is a rare type of mature T and NK neoplasm. It is more prevalent in Asia and Latin America where the Epstein-Barr virus is endemic and has been linked to the disease. Most studies have emerged from those 2 regions to evaluate best management options. There are no standards of care in the management owing to the lack of unified approach depending on the treatment region and availability of different therapy options. Several reviews have focused on the outcome of the different chemotherapy combinations. There are no systematic reviews of the toxicity of those regimens despite the fact that many of them incorporate the use of asparaginase and/or radiation in combination with chemotherapy. We have found that although integration of asparaginase and/or radiation have led to improved outcome, it was done at the expense of increased toxicity. The most recent studies are showing promising outcomes while decreasing toxicity.

Treatment of localized extranodal NK/T cell lymphoma, nasal type: a systematic review

Extranodal natural killer/T cell lymphoma (ENKTL), nasal type, presents predominantly as a localized disease involving the nasal cavity and adjacent sites, and the treatment of localized nasal ENKTL is a major issue. However, given its rarity, there is no standard therapy based on randomized controlled trials and therefore a lack of consensus on the treatment of localized nasal ENKTL. Currently recommended treatments are based mainly on the results of phase II studies and retrospective analyses. Because the previous outcomes of anthracycline-containing chemotherapy were poor, non-anthracycline-based chemotherapy regimens, including etoposide and L-asparaginase, have been used mainly for patients with localized nasal ENKTL. Radiotherapy also has been used as a main component of treatment because it can produce a rapid response. Accordingly, the combined approach of non-anthracycline-based chemotherapy with radiotherapy is currently recommended as a first-line treatment for localized nasal ENKTL. This review summarizes the different approaches for the use of non-anthracycline-based chemotherapy with radiotherapy including concurrent, sequential, and sandwich chemoradiotherapy, which have been proposed as a first-line treatment for newly diagnosed patients with localized nasal ENKTL.

One method to establish Epstein-Barr virus-associated NK/T cell lymphoma mouse models

Novel nude mice model of human NK/T cell lymphoma were established by subcutaneously injecting two NK/T cell lymphoma cell lines into the right axillary region of mice and successful passages were completed by injecting cell suspension which was obtained through a 70‐μm cell strainer. These mice models and corresponding cell clones have been successfully developed for more than 8 generations. The survival rates of both resuscitation and transplantation in NKYS and YT models were 90% and 70% correspondingly. Pathologically, the tumour cells in all passages of the lymphoma‐bearing mice and cell lines obtained from tumours were parallel to initial cell lines. Immunologically, the tumour cells expressed the characteristics of the primary and essential NK/T lymphomas. The novel mice models maintained the essential features of human NK/T cell lymphoma, and they would be ideal tools in vivo for further research of human NK/T cell lymphoma.

Concurrent Chemoradiation Therapy Followed by Consolidation Chemotherapy for Localized Extranodal Natural Killer/T-Cell Lymphoma, Nasal Type

PURPOSE

To evaluate the effectiveness of concurrent chemoradiation therapy (CCRT) with 40 Gy followed by consolidation chemotherapy for localized extranodal natural killer (NK)/T-cell lymphoma (ENKTL), nasal type.

METHODS AND MATERIALS

From August 2004 to August 2012, 62 patients with newly diagnosed stage IE to IIE ENKTL underwent CCRT followed by consolidation chemotherapy. The median RT dose was 40 Gy. Cisplatin, 30 mg/m(2), was administered weekly during the RT course. Responders to CCRT were encouraged to undergo consolidation chemotherapy. Three different consolidation chemotherapy regimens were used consecutively: VIPD (etoposide, ifosfamide, cisplatin, and dexamethasone); VIDL (etoposide, ifosfamide, and dexamethasone followed by intramuscular injection of l-asparaginase); and MIDLE (methotrexate, etoposide, ifosfamide, mesna, and l-asparaginase).

RESULTS

The median follow-up period was 49 months (range 8-112). After completion of CCRT, 56 patients (90.3%) had a complete response, 4 (6.4%) had a partial response, 1 (1.6%) had stable disease, and 1 patient (1.6%) had progressive disease (PD). Consolidation chemotherapy was recommended to 61 patients, after excluding the patient with PD, but was actually delivered to 58. Of these 58 patients, 56 (96.5%) had a complete response and 2 (3.5%) had PD. During the follow-up period, 17 patients (including 3 with PD) experienced progression. The median interval to progression was 11 months (range 1-61). Local failure developed in 6 patients, of whom, 2 had developed progression outside the RT field. For all patients, the 3-year overall survival, progression-free survival, and local control rates were 83.1%, 77.1%, and 92.4%, respectively. Grade ≥3 nonhematologic toxicity developed in only 3 patients (4.8%).

CONCLUSIONS

Excellent clinical outcomes were achieved using CCRT with 40 Gy followed by consolidation chemotherapy. Additional investigation, however, is warranted to confirm our findings.

Retrospective study of modified SMILE chemotherapy for advanced-stage, relapsed, or refractory extranodal natural killer (NK)/T cell lymphoma, nasal type

Extranodal natural killer/T cell lymphomas, nasal type (ENKLs), which are a group of non-Hodgkin lymphomas with poor prognoses, are much more common in China than in Western countries. Here, we retrospectively assessed the impact of two treatment regimens on clinical response and survival among 42 ENKL patients. All patients were diagnosed with stage IV, relapsed, or refractory ENKL. Twenty patients received modified SMILE (consisting of L-asparaginase, methotrexate, ifosphamide, etoposide, and dexamethasone) chemotherapy, and 22 control patients received CHOP (consisting of cyclophosphamide, doxorubicin, vincristine, and prednisone) treatment. Higher complete response (CR) and overall response rates (ORR) (CR 45.0 vs. 13%, ORR 70 vs. 36%) were observed among the patients treated with the modified SMILE regimen (Fisher's exact = 0.040, Pearson χ(2) P = 0.030). Similarly, a higher ORR rate was observed among Epstein-Barr virus-positive patients (ORR 50.0 vs. 18.0%, Fisher's exact = 0.049). The treatment group was also significantly associated with longer overall survival (OS) and progression-free survival (PFS) (Log-rank, P = 0.0341, P = 0.0142, respectively), but OS did not seem to be longer. Treatment-related toxicity was monitored in all patients throughout the protocol. There were no significant differences in the incidence of hematological and non-hematological toxicities between the two groups (P < 0.05), with the exception of peripheral neuropathy (treatment = 0 control = 5, Fisher's exact = 0.049).

Novel therapies for peripheral T-cell lymphomas

Peripheral T-cell lymphomas (PTCLs) are a diverse family of lymphoid neoplasms with poor prognosis. They represent approximately 6-10% of non-Hodgkin lymphomas with significant geographic variation. The median age at diagnosis varies with histology, however the majority of patients with PTCL are in their fifth or sixth decade of life. Until recently clinical development of new agents for PTCL was slow due to difficulties in making the correct diagnosis, lack of uniform classification and combination of rarity and biologic diversity of the group. In the last 5 years, significant advances were made to overcome these obstacles, leading to the approval of three new agents for relapsed and refractory PTCL by the Food and Drug Administration, based on well conducted prospective studies. Pralatrexate, a unique antifol, was the first agent granted approval, followed by romidepsin, a histone deacetylase inhibitor, and brentuximab vedotin, an immunoconjugate. Owing to the unique nature of these agents, durable responses were seen in patients with highly refractory disease, and some of these responses are long lasting after discontinuation of therapy. Accumulating data indicate that these novel agents have little cumulative toxicity and can be administered continuously to patients who are not candidates for consolidative stem-cell transplantation (SCT), with little impact on quality of life. They might also provide a new salvage option for patients eligible for SCT with no impact on autologous stem-cell collection or subsequent engraftment. New studies are underway to evaluate efficacy and safety of new agents in combination regimens for both newly diagnosed and relapsed/refractory PTCL. Several other investigational drugs showed promise in recent trials. This review focuses on novel therapies for T-cell lymphomas, their place in current treatment paradigms and future directions.

Successful treatment of chemotherapy-refractory angioimmunoblastic T cell lymphoma with cyclosporin A

Angioimmunoblastic T cell lymphoma (AITL) is a rare subtype of T cell non-Hodgkin lymphoma. The standard therapeutic strategy for AITL has not yet been established, and its prognosis remains poor. This report concerns the effect of cyclosporin A (CsA) on chemotherapy-refractory AITL. A 68-year-old female with AITL with systemic symptoms, such as high fever, skin rash and generalized lymphadenopathy, was initially treated with conventional cytotoxic chemotherapies using alkylators, anthracyclines and corticosteroids, which failed to induce remission. However, CsA (4 mg/kg/day) plus dexamethasone treatment resulted in a dramatic regression of the tumors and amelioration of systemic symptoms and induced complete remission (CR) within 2 weeks. Currently, the patient's CR has continued for more than 18 months with CsA maintenance therapy. Our experience and previously reported findings suggest that CsA may constitute an alternative treatment option for AITL, even though the use of conventional cytotoxic chemotherapy continues to be the first-line therapy on an empirical basis.

Physiological Oxidants Induce Apoptosis and Cell Cycle Arrest in a Multidrug-resistant Natural Killer Cell Line, NK-YS

Natural-killer (NK) cell-derived malignant tumors, such as angiocentric lymphoma, is often resistant to various chemotherapeutic agents and follows an aggressive clinical course. We report the effects of physiological oxidants (hydrogen peroxide, H2O2; sodium hypochlorite, NaOCl and monochloramine, NH2Cl) on the cell growth and cell death in a multidrug-resistant NK tumor cell line, NK-YS. Among the oxidants tested, NH2Cl was most cytotoxic, in which more than 90% of the cells died at 150 nmol/1 x 10(6) cells. H2O2 was less cytotoxic, whereas NaOCl showed no significant cell death at this dose. The cell death induced by NH2Cl was accompanied by DNA cleavage and caspase activation, which suggested apoptosis. In addition, lower dose of NH2Cl (70 nmol/1 x 10(6) cells) retarded cell growth and inhibited the cell cycle transition from G1 to S. This cell cycle arrest accompanied a decrease in the phosphorylation of retinoblastoma tumor suppressor protein at serine 795. These observations suggest that NH2Cl may induce apoptotic cell death and growth arrest in multidrug-resistant NK cell tumors.

Cyclosporine A for chemotherapy-resistant subcutaneous panniculitis-like T cell lymphoma with hemophagocytic syndrome

Subcutaneous panniculitis-like T cell lymphoma (SPTL) is a rare subtype of non-Hodgkin lymphoma for which a definitive therapeutic strategy has not been established yet. We report a case of chemotherapy-resistant SPTL with hemophagocytic syndrome (HPS) which was successfully treated with cyclosporine A (CsA) plus methylprednisolone (mPSL), and also reviewed 11 SPTL cases treated with CsA, previously reported in the literature. Our patient was a 38-year-old female with SPTL. The disease progressed despite conventional chemotherapy using cytotoxic agents including alkylators, anthracyclins or purine analogues, and, after 2 months of chemotherapy, was eventually complicated by HPS and disseminated intravascular coagulation (DIC). CsA (4 mg/kg/day) plus mPSL treatment dramatically improved HPS with DIC, reduced subcutaneous tumors within 2 weeks, and finally induced complete remission (CR) after 3 months. Currently, the patient has maintained CR while being treated with CsA for 12 months. In addition to our case, 9 of 11 SPTL cases were successfully treated with CsA, and 8 were induced to CR. Time to first response to CsA was within 2 weeks in most cases, regardless of prior treatment or the co-occurrence of HPS. Our case and this first comprehensive review on CsA for SPTL suggest that CsA may constitute a candidate treatment strategy for SPTL.

Treatment of Aggressive NK-Cell Leukemia: A Case Report and Review of the Literature

Aggressive NK-cell leukemia is a rare malignancy with neoplastic proliferation of natural killer cells. It often presents with constitutional symptoms, a rapid declining clinical course, and a poor prognosis with a median survival of a few months. The disease is usually resistant to cytotoxic agents, and no treatment has emerged as the standard of care for these patients. We report a case of an 18-year-old male who obtains complete remission following two lines of combination chemotherapy. We describe in details our regimens for induction chemotherapy and perform a review of existing literature concerning treatment of aggressive NK-cell leukemia.

Treatment of localized extranodal NK/T cell lymphoma, nasal type

Extranodal NK/T cell lymphoma predominantly presents as a localized disease in the upper aerodigestive tract from the nasal cavity to the hypopharynx. Because radiotherapy has better outcomes than chemotherapy with reduced locoregional failure, it should be considered the preferred first-line therapy. However, the addition of chemotherapy is appropriate as part of the initial treatment because of the frequent systemic progression or relapse after radiotherapy. At present, the combination of radiotherapy and chemotherapy can be considered an effective treatment option, and the promising results of recent prospective studies with concurrent chemoradiotherapy support this treatment strategy. In contrast, intensive chemotherapy should be considered as initial treatment for patients with tumors in non-upper-aerodigestive-tract sites, such as skin or intestine because they usually progress to systemic disease. Likewise, for patients with poor prognostic factors, such as a high NK lymphoma prognostic index, autologous stem cell transplantation during remission and additional treatments with central nervous system prophylaxis may be beneficial. However, the precise role of these treatments needs to be clarified further by prospective clinical trials. Thus, a prospective study is warranted to explore a risk-adapted treatment strategy of applying initial chemoradiotherapy and additional consolidation treatments.

Phase II Trial of Concurrent Radiation and Weekly Cisplatin Followed by VIPD Chemotherapy in Newly Diagnosed, Stage IE to IIE, Nasal, Extranodal NK/T-Cell Lymphoma: Consortium for Improving Survival of Lymphoma Study

Purpose

On the basis of the benefits of frontline radiation in early-stage, extranodal, natural killer (NK)/T-cell lymphoma (ENKTL), we conducted a phase II trial of concurrent chemoradiotherapy (CCRT) followed by three cycles of etoposide, ifosfamide, cisplatin, and dexamethasone (VIPD).

Patients and Methods

Thirty patients with newly diagnosed, stages IE to IIE, nasal ENKTL received CCRT (ie radiation 40 to 52.8 Gy and cisplatin 30 mg/m2 weekly). Three cycles of VIPD (etoposide 100 mg/m2 days 1 through 3, ifosfamide 1,200 mg/m2 days 1 through 3, cisplatin 33 mg/m2 days 1 through 3, and dexamethasone 40 mg days 1 through 4) were scheduled after CCRT.

Results

All patients completed CCRT, which resulted in 100% response that included 22 complete responses (CRs) and eight partial responses (PRs). The CR rate after CCRT was 73.3% (ie, 22 of 30 responses; 95% CI, 57.46 to 89.13). Twenty-six of 30 patients completed the planned three cycles of VIPD, whereas four patients did not because they withdrew (n = 2) or because they had an infection (n = 2). The overall response rate and the CR rate were 83.3% (ie; 25 of 30 responses; 95% CI, 65.28 to 94.36) and 80.0% (ie, 24 of 30 responses; 95% CI, 65.69 to 94.31), respectively. Only one patient experienced grade 3 toxicity during CCRT (nausea), whereas 12 of 29 patients experienced grade 4 neutropenia. The estimated 3-year, progression-free and overall survival rates were 85.19% (95% CI, 72.48 to 97.90) and 86.28% (95% CI, 73.97 to 98.59), respectively.

Conclusion

Patients with newly diagnosed, stages IE to IIE, nasal ENKTL are best treated with frontline CCRT.

Phase I study of dexamethasone, methotrexate, ifosfamide, L-asparaginase, and etoposide (SMILE) chemotherapy for advanced-stage, relapsed or refractory extranodal natural killer (NK)/T-cell lymphoma and leukemia

Extranodal natural killer (NK)/T-cell lymphoma, nasal type, and aggressive NK-cell leukemia are rare, and their standard therapy has not been established. They are Epstein-Barr virus-associated lymphoid malignancies, and tumor cells express P-glycoprotein leading to multidrug resistance of the disease. Patients with stage IV, relapsed or refractory diseases have a dismal prognosis, with survival measured in months only. To develop an efficacious chemotherapeutic regimen, we conducted a dose-escalation feasibility study of a new chemotherapeutic regimen, SMILE, comprising the steroid dexamethasone, methotrexate, ifosfamide, L-asparaginase, and etoposide. The components of SMILE are multidrug resistance-unrelated agents and etoposide. Etoposide shows both in vitro and in vivo efficacy for Epstein-Barr virus-associated lymphoproliferative disorders. Eligible patients had newly diagnosed stage IV, relapsed or refractory diseases after first-line chemotherapy, were 15-69 years of age, and had satisfactory performance scores (0-2). Four dose levels of methotrexate and etoposide were originally planned to be evaluated. At level 1, six patients with extranodal NK/T-cell lymphoma, nasal type, were enrolled. Their disease status was newly diagnosed stage IV (n = 3), first relapse (n = 2), and primary refractory (n = 1). All of the first three patients developed dose-limiting toxicities, and one of them died of sepsis with grade 4 neutropenia. A protocol revision stipulating early granulocyte colony-stimulating factor administration was made. Two out of three additional patients developed dose-limiting toxicities that were all manageable and transient. For the six enrolled patients, the overall response rate was 67% and the complete response rate was 50%. Although its safety and efficacy require further evaluation, we recommend a SMILE chemotherapy dose level of 1 for further clinical studies.

Progress in understanding and managing natural killer-cell malignancies

The World Health Organization classification of haematolymphoid tumours recognizes three categories of natural killer (NK)-cell neoplasms: blastic NK-cell lymphoma, aggressive NK-cell leukaemia, and extranodal NK/T-cell lymphoma, nasal-type. Recent studies indicate that CD4+CD56+ blastic NK-cell lymphoma is of plasmacytoid dendritic cell origin, and true tumours of precursor NK-cell origin may be present mainly in the CD4-CD56+ subset. Myeloid/NK-cell precursor acute leukaemia may also develop from precursor NK cells. However, because the developmental pathway of normal NK cells is not well understood, tumours of precursor NK-cell origin are not clearly identified. Among mature NK-cell tumours, extranodal NK/T-cell lymphoma is relatively common in Asia and Latin America. In localized disease, chemoradiotherapy seems to be promising, and in advanced disease, new combination chemotherapies are under active investigation. Aggressive NK-cell leukaemia is rare and has a poor prognosis. Because NK-cell neoplasms are rare and difficult to manage, rigorous studies are required for their understanding and management.

Inhibition of interferon-gamma-activated nuclear factor-kappa B by cyclosporin A: A possible mechanism for synergistic induction of apoptosis by interferon-gamma and cyclosporin A in gastric carcinoma cells

We previously reported synergistic induction of apoptosis by IFN-gamma plus either cyclosporin A (CsA) or tacrolimus (FK506) in gastric carcinoma cells. In this study, we aimed to elucidate the mechanism for this synergistic induction of apoptosis. IFN-gamma plus CsA synergistically induced caspase-3 mediated apoptosis in gastric carcinoma cells. Although IFN-gamma induced activation of signal transducer and activator of transcription1 (STAT1) and expression of interferon regulatory factor-1 (IRF-1) mRNA, IFN-gamma alone was not able to induce caspase-3 activation and apoptosis. When gastric carcinoma cells were treated with cyclohexamide, a protein synthesis inhibitor, following IFN-gamma pretreatment, caspase-3 was activated, and apoptosis was markedly induced. These findings suggest the existence of IFN-gamma-induced anti-apoptotic pathway and we evaluated the effect of IFN-gamma and CsA on calcium-sensitive nuclear factor-kappa B (NF-kappa B) activation. IFN-gamma increased intracellular calcium ion concentration ([Ca(2+)](i)) consisting of a spike and a sustained phase, and the latter was completely abrogated by CsA. Activation of NF-kappa B occurred in response to IFN-gamma, and which was markedly inhibited by either CsA or FK506. NF-kappa B decoy also enhanced the cytotoxic effect of IFN-gamma. These results suggest that IFN-gamma may simultaneously induce the STAT1-mediated apoptotic pathway and the anti-apoptotic pathway through calcium-activated NF-kappa B and that inhibition of the latter by CsA may result in dominance of the apoptosis-inducing pathway.

Induction and characterization of cutaneous lymphocyte antigen on natural killer cells

Cutaneous lymphocyte antigen (CLA) has been reported to be expressed mainly by memory/effector T lymphocytes infiltrating inflammatory skin lesions and cutaneous T-cell lymphoma. It has been suggested that CLA is a specific homing receptor, facilitating the T-cell migration into skin lesions, and also an indicator of the skin-homing T-cell subset. In the present study, we investigated the expression of CLA in natural killer (NK) cells defined phenotypically as surface CD3- and CD56+ cells in peripheral blood. CLA was definitely expressed on CD3-CD56+ cells at a level comparable to CD3+ cells in peripheral blood of normal Japanese volunteers. After in vitro stimulation of peripheral blood mononuclear cells with interleukin 2 (IL-2) and IL-12, there was a significant increase in the number and percentage of CLA+ NK cells but not CLA+ T cells (P < 0.01). To analyse the characteristics of CLA expressed by NK cells, we investigated a CLA+ NK-leukaemia cell line, NK-YS, established from a patient with NK leukaemia/lymphoma with skin infiltration. In the in vitro study, the CLA-expressing NK-leukaemic cell line bound to E-selectin-transfected cells and was inhibited by HECA 452 antibody or neuraminidase treatment of leukaemic cells. These findings suggest that CLA expressed by NK cells is a homing receptor for the E-selectin molecule and may explain skin infiltration by NK cells and NK lymphoma cells analogous to T cells. An NK-cell subset expressing CLA must play an important role in host defence against microorganisms and neoplasms in skin lesions.

Risk of etoposide-related acute myeloid leukemia in the treatment of Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis

We studied the impact of etoposide on the prognosis of 81 patients (77 of whom were children <15 years old) with Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis (EBV-HLH). The study group received a median cumulative dose of 1,500 mg/m2 etoposide (range, 0-14,550 mg/m2), with a median follow-up period of 44 months (range, 20-88 months) from the diagnosis. Only 1 patient, who received 3150 mg/m2 etoposide, developed therapy-related acute myeloid leukemia (t-AML), at 31 months after diagnosis. Excluding 9 patients who underwent hemopoietic stem cell transplantation during the course of treatment, the prognosis was poorer for those patients who received less than a 1,000 mg/m2 cumulative dose of etoposide. Our results indicate that the risk of etoposide-related t-AML is low. An appropriate dosage of etoposide for the treatment of EBV-HLH would be in the range of 1,000 to 3,000 mg/m2. However, even at these doses, care must be taken to prevent the rare risk of t-AML.