To explore a more effective treatment for newly diagnosed stage IV, relapsed, or refractory extranodal natural killer/T-cell lymphoma, nasal type (ENKL), we conducted a phase II study of the steroid ...(dexamethasone), methotrexate, ifosfamide, L-asparaginase, and etoposide (SMILE) regimen.
Patients with newly diagnosed stage IV, relapsed, or refractory disease and a performance status of 0 to 2 were eligible. Two cycles of SMILE chemotherapy were administered as the protocol treatment. The primary end point was the overall response rate (ORR) after the protocol treatment.
A total of 38 eligible patients were enrolled. The median age was 47 years (range, 16 to 67 years), and the male:female ratio was 21:17. The disease status was newly diagnosed stage IV in 20 patients, first relapse in 14 patients, and primary refractory in four patients. The eligibility was revised to include lymphocyte counts of 500/μL or more because the first two patients died from infections. No treatment-related deaths were observed after the revision. The ORR and complete response rate after two cycles of SMILE chemotherapy were 79% (90% CI, 65% to 89%) and 45%, respectively. In the 28 patients who completed the protocol treatment, 19 underwent hematopoietic stem-cell transplantation. The 1-year overall survival rate was 55% (95% CI, 38% to 69%). Grade 4 neutropenia was observed in 92% of the patients. The most common grade 3 or 4 nonhematologic complication was infection (61%).
SMILE chemotherapy is an effective treatment for newly diagnosed stage IV, relapsed or refractory ENKL. Myelosuppression and infection during the treatment should be carefully managed.
The so-called "double-hit" and "double-protein-expression" lymphoma with
and
rearrangements is a rare, mature B-cell neoplasm characterized by a germinal center B-cell phenotype, abundant protein ...expression of MYC and BCL2, rapid disease progression, and a poor prognosis. In this study, we showed the potential benefit of the BCL2 inhibitor venetoclax in the treatment of this disease. Immunohistochemical studies of the lymphoma tissues confirmed that overexpression of MYC and BCL2 was observed more frequently in this subtype than in other germinal center B-cell-like diffuse large B-cell lymphomas. In contrast, another pro-survival protein MCL1 was less expressed in this subtype, even when compared with its expression in the non-"double-hit" and "double-protein-expression" type. Furthermore,
studies using two "double-hit" and "double-protein-expression" lymphoma-derived cell lines, Karpas231 and OCI-Ly8, clearly showed that a low concentration of venetoclax, but not the MCL1 inhibitor S63845, was sufficient to induce apoptosis in the two lines, compared with in other germinal center B-cell-derived cell lines, BJAB and SU-DHL10. These results indicate that the survival of this type of lymphoma depends predominantly on BCL2 rather than on MCL1. Unexpectedly, we found that venetoclax not only disrupts the interaction between BCL2 and the pro-apoptotic protein BIM, but also leads to dephosphorylation of BCL2 and further downregulates MCL1 protein expression, probably through modulation of the protein phosphatase 2A B56α activity in Karpas231 and OCI-Ly8. Indeed, a low concentration of venetoclax induced substantial apoptosis in the primary lymphoma cells, regardless of high protein expression of MCL1 associated with venetoclax resistance. Venetoclax clearly triggers the signal transduction related to BCL2 and MCL1 in "double-hit" and "double-protein-expression" lymphoma cells.
To explore a more effective treatment for localized nasal natural killer (NK)/T-cell lymphoma, we conducted a phase I/II study of concurrent chemoradiotherapy.
Treatments comprised concurrent ...radiotherapy (50 Gy) and 3 courses of dexamethasone, etoposide, ifosfamide, and carboplatin (DeVIC). Patients with a newly diagnosed stage IE or contiguous IIE disease with cervical node involvement and a performance status (PS) of 0 to 2 were eligible for enrollment. The primary end point of the phase II portion was a 2-year overall survival in patients treated with the recommended dose.
Of the 33 patients enrolled, 10 patients were enrolled in the phase I portion and a two thirds dose of DeVIC was established as the recommended dose. Twenty-seven patients (range, 21 to 68; median, 56 years) treated with the recommended dose showed the following clinical features: male:female, 17:10; stage IE, 18; stage IIE, 9; B symptoms present, 10; elevated serum lactate dehydrogenase, 5; and PS 2, 2. With a median follow-up of 32 months, the 2-year overall survival was 78% (95% CI, 57% to 89%). This compared favorably with the historical control of radiotherapy alone (45%). Of the 26 patients assessable for a response, 20 (77%) achieved a complete response, with one partial response. The overall response rate was 81%. The most common grade 3 nonhematologic toxicity was mucositis related to radiation (30%). No treatment-related deaths were observed.
Concurrent chemoradiotherapy using multidrug resistance-nonrelated agents and etoposide is a safe and effective treatment for localized nasal NK/T-cell lymphoma and warrants further investigation.
L‐asparaginase (L‐ASNase) is an important branch of chemotherapy for acute lymphoblastic leukemia (ALL) and some types of non‐Hodgkin's lymphoma, including natural killer (NK)‐cell lymphoma. Although ...it mediates hydrolysis of asparagine (Asn) and glutamine (Gln), which are variably required for cancer cell survival, the relative contribution of Asn and Gln depletion to the anti‐tumor activity in therapeutic doses is unclear in ALL and malignant lymphoma. Here we demonstrate that L‐ASNase exerts cytotoxicity through targeting the Gln addiction phenotype in lymphoid cell lines. A clinically attainable intermediate dose of L‐ASNase induced massive apoptosis in ALL Jurkat and mantle cell lymphoma Jeko cell lines, while a low dose of L‐ASNase effectively killed NK‐cell lymphoma cells. In the lymphoid cell lines Jurkat and Jeco, deprivation of Gln but not Asn specifically suppressed cell growth and survival, and phenocopied the action of L‐ASNase. L‐ASNase treatment and Gln deprivation dramatically disrupted the refilling of the tricarboxylic acid (TCA) cycle by intracellular glutamate (Glu) and disturbed the mitochondrial integrity, which were alleviated by various anaplerotic TCA cycle intermediates, suggesting a direct contribution of glutaminase activity of L‐ASNase. The action of L‐ASNase differs between Jurkat cells and NK‐cell lymphoma cells, according to their dependence on Gln and Asn. Furthermore, we observed that high expression of glutaminase GLS1 is associated with increased sensivity to L‐ASNase in pediatric B lineage ALL. Our results redefine L‐ASNase as a therapeutic agent targeting Gln addiction in certain lymphoid cells and offer an additional basis for predicting L‐ASNase sensitivity and engineering selective L‐ASNase derivatives for leukemia and lymphoma.
L‐asparaginase (L‐ASNase) is an important branch of chemotherapy for acute lymphoblastic leukemia (ALL) and some types of non‐Hodgkin's lymphoma, including natural killer (NK)‐cell lymphoma. Relative contribution of Asn and Gln depletion to L‐ASNase activity is unclear in ALL and malignant lymphoma. The present study demonstrates that L‐ASNase mediates the cytotoxicity through targeting Gln addiction phenotype in lymphoid cell lines.
We conducted a retrospective Japan–Korea multicenter study to better elucidate the clinicopathologic features and therapeutic modalities for aggressive natural killer cell leukemia (ANKL). A total of ...34 patients were analyzed. The median age of the patients was 40 years. Among the patients in the study, four had a history of Epstein–Barr virus‐related disorders. Three types of ANKL cells were categorized according to their morphological features. Leukemic cells were below 20% in both peripheral blood and bone marrow of 11 patients. The clinical characteristics and prognoses of these 11 patients did not differ significantly from those of the others. As an initial therapy, l‐asparaginase chemotherapy resulted in a better response. A total of six patients received allogeneic hematopoietic stem cell transplantation (HSCT) and two received autologous HSCT, with all in non‐complete remission (CR). After HSCT, four with allogeneic and one with autologous HSCT reached CR. Median survival of all patients was 51 days. Median survival for the patients with and without HSCT were 266 and 36 days, respectively. A total of two patients with allogeneic HSCT were alive and in CR. All patients without HSCT died of ANKL. The use of l‐asparaginase was indicated as a factor for longer survival (HR 0.33, 95% confidence interval; 0.13–0.83, P = 0.02). Early diagnosis of ANKL, l‐asparaginase‐based chemotherapy and allogeneic HSCT might lead to improved patient outcomes. (Cancer Sci 2012; 103: 1079–1083)
Activation‐induced cell death (AICD) mediated by the Fas/Fas ligand (FasL) system plays a key role in regulating immune response. Although normal natural killer (NK) cells use this system for their ...homeostasis, malignant NK cells seem to disrupt the process. Extranodal NK/T‐cell lymphoma, nasal type (ENKL) is a rare but fatal disease, for which novel therapeutic targets need to be identified. We confirmed that ENKL‐derived NK cell lines NK‐YS and Hank1, and primary lymphoma cells expressed procaspase‐8/FADD‐like interleukin‐1β‐converting enzyme (FLICE) modulator and cellular FLICE‐inhibitory protein (c‐FLIP), along with Fas and FasL. Compared with Fas‐sensitive Jurkat cells, NK‐YS and Hank1 showed resistance to Fas‐mediated apoptosis in spite of the same expression levels of c‐FLIP and the death‐inducing signaling complex (DISC) formation. Unexpectedly, the long isoform of c‐FLIP (c‐FLIPL) was coimmunoprecipitated with Fas predominantly in both ENKL‐derived NK cell lines after Fas ligation. Indeed, c‐FLIPL was more sufficiently recruited to the DISC in both ENKL‐derived NK cell lines than in Jurkat cells after Fas ligation. Knockdown of c‐FLIPL per se enhanced autonomous cell death and restored the sensitivity to Fas in both NK‐YS and Hank1 cells. Although ENKL cells are primed for AICD, they constitutively express and efficiently utilize c‐FLIPL, which prevents their Fas‐mediated apoptosis. Our results show that c‐FLIPL could be a promising therapeutic target against ENKL.
Extranodal natural killer (NK)/T‐cell lymphoma, nasal type (ENKL)‐derived NK cells are primed for activation‐induced cell death (AICD) like activated normal NK cells. ENKL‐derived NK cells efficiently recruit the long isoform of c‐FLIP to the death‐inducing signaling complex and show resistance to AICD.
Epstein-Barr virus (EBV) infection is highly prevalent in humans and is implicated in various diseases, including cancer
. Chronic active EBV infection (CAEBV) is an intractable disease classified as ...a lymphoproliferative disorder in the 2016 World Health Organization lymphoma classification
. CAEBV is characterized by EBV-infected T/natural killer (NK) cells and recurrent/persistent infectious mononucleosis-like symptoms
. Here, we show that CAEBV originates from an EBV-infected lymphoid progenitor that acquires DDX3X and other mutations, causing clonal evolution comprising multiple cell lineages. Conspicuously, the EBV genome in CAEBV patients harboured frequent intragenic deletions (27/77) that were also common in various EBV-associated neoplastic disorders (28/61), including extranodal NK/T-cell lymphoma and EBV-positive diffuse large B-cell lymphoma, but were not detected in infectious mononucleosis or post-transplant lymphoproliferative disorders (0/47), which suggests a unique role of these mutations in neoplastic proliferation of EBV-infected cells. These deletions frequently affected BamHI A rightward transcript microRNA clusters (31 cases) and several genes that are essential for producing viral particles (20 cases). The deletions observed in our study are thought to reactivate the lytic cycle by upregulating the expression of two immediate early genes, BZLF1 and BRLF1
, while averting viral production and subsequent cell lysis. In fact, the deletion of one of the essential genes, BALF5, resulted in upregulation of the lytic cycle and the promotion of lymphomagenesis in a xenograft model. Our findings highlight a pathogenic link between intragenic EBV deletions and EBV-associated neoplastic proliferations.
Peripheral T‐ or natural killer (NK)‐cell lymphomas are rare and difficult‐to‐recognize diseases. It remains arduous to distinguish between NK cell‐ and cytotoxic T‐lymphocyte‐derived lymphomas ...through routine histological evaluation. To clarify the cells of origin, we focused on NK‐cell receptors and examined the expression using immunohistochemistry in 22 cases with T‐ and NK‐cell neoplasms comprising angioimmunoblastic T‐cell lymphoma, anaplastic lymphoma kinase (ALK)‐positive and ‐negative anaplastic large‐cell lymphomas, extranodal NK/T‐cell lymphoma, nasal type, monomorphic epitheliotropic intestinal T‐cell lymphoma, aggressive NK‐cell leukemia, and other peripheral T‐cell lymphomas. Inhibitory receptor leukocyte immunoglobulin‐like receptor subfamily B member 1 (LILRB1) was detected in 14 (64%) cases, whereas activating receptors DNAM1, NKp46, and NKG2D were expressed in 7 (32%), 9 (41%), and 5 (23%) cases, respectively. Although LILRB1 was detected regardless of the disease entity, the activating NK‐cell receptors were expressed predominantly in TIA‐1‐positive neoplasms (DNAM1, 49%; NKp46, 69%; and NKG2D, 38%). In addition, NKp46 and NKG2D were detected only in NK‐cell neoplasms and cytotoxic T‐lymphocyte‐derived lymphomas including monomorphic epitheliotropic intestinal T‐cell lymphoma. One Epstein‐Barr virus‐harboring cytotoxic T‐lymphocyte‐derived lymphoma mimicking extranodal NK/T‐cell lymphoma, nasal type lacked these NK‐cell receptors, indicating different cell origin from NK and innate‐like T cells. Furthermore, NKG2D expression showed a negative impact on survival among the 22 examined cases, which mainly received the standard chemotherapy regimen (log‐rank test, P = .024). We propose that the presence of activating NK‐cell receptors may provide new insights into understanding peripheral T‐cell lymphomas and characterizing them as innate‐like T‐cell neoplasm.
It remains difficult to distinguish between NK‐cell‐ and cytotoxic T‐lymphocyte‐derived lymphomas through routine histological evaluation. Cytotoxic T‐lymphocyte‐derived lymphomas are characterized as innate‐like T‐cell neoplasms by the expression of activating NK‐cell receptors. NKG2D expression might show a negative impact on survival in T‐ and NK‐cell lymphoma cases receiving the standard CHOP‐like regimen.
Light-chain plasma cell myeloma (LC-PCM) is a PCM subtype in which only immunoglobulin light-chain is secreted. However, the absence of immunoglobulin heavy-chain (IGH) production in this condition ...has not been fully elucidated. To address this issue, we retrospectively analyzed patients at our center with LC-PCM and found a group who had only split signals of
IGH
gene derived from 14q32/
IGH
translocations by fluorescence in situ hybridization (FISH). Six patients were identified with only split signals of the
IGH
gene derived from 14q32/
IGH
translocations. Five of these patients were newly diagnosed, while one had IgG-λ PCM at presentation, which transformed to λ LC-PCM after treatment. The translocation partners were identified in four patients: two cases of (11;14)(q13;q32) and two cases of (4;14)(p16;q32). The development of LC-PCM appears to be explained by the application of allelic exclusion in these patients, such that 14q32/
IGH
translocation in one allele contributes to the pathogenesis of PCM and the subsequent loss of the other allele is responsible for the loss of IGH production. These findings suggest that a FISH pattern of
IGH
with “split and loss” may constitute a unique subgroup of LC-PCM.
The introduction of all-
trans
retinoic acid (ATRA) has made acute promyelocytic leukemia (APL) a curable disease; however, early death prior to the completion of treatment remains a problem. In ...quantitative evaluation of response to ATRA treatment, lymphocytes must be excluded as they do not originally have t(15;17). We categorized peripheral blood leukocytes by nuclear morphology into polymorphonuclear cells (PMNs) comprising segmented granulocytes, and non-polymorphonuclear cells (NPMs) which includes lymphocytes, monocytes, band cells, and immature myeloid cells. We consecutively evaluated the ratio of t(15;17)-positive cells using fluorescence in situ hybridization in eight newly diagnosed patients with APL. We confirmed the differentiation of APL cells until cytogenetic complete remission; the association of a decrease of t(15;17)-positive NPMs and an increase of t(15;17)-positive PMNs was followed by a decrease of t(15;17)-positive PMNs. The kinetic pattern of t(15;17)-positive NPMs and PMNs was consistent in most patients, irrespective of leukocyte counts at diagnosis, additional chromosomal changes, and ATRA with or without chemotherapies. Kinetic analysis enables us to evaluate treatment response and the recovery of normal hematopoiesis in individuals.