Acute Adult T-cell Leukemia/lymphoma Research Articles

Overview of Targeted Therapies for Adult T-Cell Leukemia/Lymphoma.

Adult T-Cell Leukemia/lymphoma (ATL) is the first human malignancy associated with a chronic infection by a retrovirus, the human T-cell lymphotropic virus type I (HTLV-I). ATL occurs, after a long latency period, only in about 5% of 10-20 millions infected individuals. ATL has a dismal prognosis with a median survival of less than 1 year, mainly due to its resistance to chemotherapy and to a profound immunosuppression. The viral oncoprotein, Tax, plays a major role in ATL oncogenic transformation by interfering with cell proliferation, cell cycle, apoptosis, and DNA repair. The diversity in ATL clinical features and prognosis led to Shimoyama classification of ATL into four clinical subtypes (acute, lymphoma, chronic, and smoldering) requiring different therapeutic strategies. Clinical trials, mainly conducted in Japan, demonstrated that combination of chemotherapy could induce acceptable response rate in the lymphoma subtype but not in acute ATL. However, long-term prognosis remains poor for both subtypes, due to a high relapse rate. Similarly, whether managed by a watchful waiting or treated with chemotherapy, the indolent forms (smoldering and chronic) have a poor long-term outcome. An international meta-analysis showed improved survival in the leukemic subtypes of ATL (chronic, smoldering as well as a subset of the acute subtype) with the use of two antiviral agents, zidovudine and interferon-alpha, and accordingly, this combination should be considered the standard first-line treatment in this context. ATL patients with lymphoma subtype benefit from induction chemotherapy, given simultaneously or sequentially with an antiviral combination of zidovudine and interferon-alpha. Allogeneic hematopoietic stem cells transplantation remains a promising and potentially curative approach but is limited to a small number of patients. Novel drugs such as arsenic trioxide in combination with interferon-alpha or monoclonal antibodies such as anti-CXCR4 have shown promising results and warrant further investigation.

Impact of Chromosomal Abnormalities in Acute and Lymphoma Types Adult T-Cell Leukemia-Lymphoma

Background:Adult T-cell leukemia-lymphoma (ATL), which is a hematological malignancy related to human T-lymphotropic virus type I (HTLV-1), is known as a malignant lymphoid disease with poor prognosis. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is considered a treatment modality to contribute prolonging the survival in some population of patients (Katsuya H et al. 2015 Blood). A small study indicated that ATL cells frequently have chromosomal abnormalities including various numerical aberrations and complex structural abnormalities (Kamada N et al. Cancer Res. 1992). However, there has been no large study to examine the relationship between chromosomal abnormalities and survival. Here we report the impact of chromosomal abnormalities on survival in ATL patients with conventional chemotherapy.Patients and Methods:In this study, we extracted a population of patients from the database of ATL-PI project, which is a nation-wide survey of ATL patients newly diagnosed between January 2000 and May 2009, and the overall results were reported elsewhere (Katsuya H et al. JCO 2012, Blood 2015). Fifteen hundred and twelve patients were registered in this project, and we excluded the patients who received allo-HSCT, and who were diagnosed with smoldering and chronic type ATL. Moreover, patients whose chromosomal analysis with G-banding stain showed normal, multiploid or no mitosis, or no information on chromosomal analysis and on the factors to determine the ATL-PI were also excluded. As a consequence, 210 patients with acute (n=157) and lymphoma (n=53) types were selected for this analysis. Abnormal karyotypes were analyzed from the aspect of numerical and structural break points. To identify the specific abnormalities and to avoid the secondary changes, the stem-line karyotype, which meant the simplest abnormal clone, was used as the representative karyotype for this study. A statistical analysis was performed with 'EZR' (Kanda T. BMT 2013). We examined an overall survival (OS) in relation to chromosomal abnormalities using cox proportional hazard regression model, and p-value of less than 0.05 was considered as statistically significant.Results:Among the 210 patients, 119 and 91 patients were male and female, respectively. The median age of patients was 66 years (40-89). With respect to other factors of ATL-PI, the median level of soluble interleukin-2 receptor (sIL-2R), serum albumin, were 30800 U/mL (620-1,219,000), 3.6 g/dL (1.6-5.3), respectively. Almost all patients were diagnosed with stage II-IV of clinical stage (n=200), and almost half of patients certified 2-4 of ECOG-PS (n=113). Sixty-nine, 106, and 35 patients were classified as high, intermediate and low risk by ATL-PI, respectively. Specimens used for chromosomal analysis were taken from lymph nodes (n=77), bone marrow (n=72), peripheral blood (n=50), pleural fluids (n=4), ascites (n=4) and 1 each of stomach, sinusoidal tumor, and tonsillar lesions. The median number of numerical abnormalities and marker chromosomes were 2 (0-20) and 1 (0-20), and the median number of structural break points was 6 (0-21). The numerical abnormalities were loss of sex chromosomes (31%) followed in decreasing order by -14 (24%), -13 (19%), -9 (12%) and -17 (12%) while the structural break points were located at 1p (30%), 3q (30%), 14q (30%), 6q (26%) and 1q (22%). The median OS was 286 days (1-2565). ECOG-PS, serum albumin level, sIL-2R, and structural break points at 9q or 19p, and the number of structural break points over 4 or 5 points were shown to be the significant factors affecting the survival by univariate analysis. Then, the multivariate analysis indicated that 2-4 of ECOG-PS (HR: 2.021, 95%CI: 1.436-2.791, p<0.001), serum albumin level < 3.5 g/dl (HR: 1.631, 95%CI: 1.282-2.074, P<0.001), and chromosomally structural break points at 9q (HR: 1.584, 95%CI: 1.096-2.289, p<0.001) and 19p (HR: 1.765, 95%CI: 1.038-2.999, p<0.001) were factors that negatively contributed to OS.Discussions and Conclusion:This is the first large study showing the impact of chromosomal abnormality in acute and lymphoma types ATL on OS. It demonstrated that structural break points at 9q and 19p were the independent risk factors for OS in addition to those of ATL-PI. DisclosuresKatsuya:The Uehara Memorial Foundation: Research Funding. Utsunomiya:Daiichi Sankyo Co., Ltd.: Speakers Bureau. Tsukasaki:Daiichi Sankyo Co., Ltd.: Consultancy; Takeda: Research Funding. Suzumiya:Takeda: Honoraria; Astellas: Research Funding; Kyowa Hakko kirin: Research Funding; Chugai: Honoraria, Research Funding; Toyama Chemical: Research Funding; Eisai: Honoraria, Research Funding.

O2-8-5 - Possible stimulatory immune checkpoint molecules releasing allows adult T-cell leukemia/lymphoma development

The interleukin (IL)-2 receptor α chain (IL-2Rα, CD25) and CD30 are cell membrane proteins expressed on activated T-cell. High levels of soluble cytokine receptors, soluble IL-2Rα (sIL-2R) and soluble CD30 (sCD30) are detected in the serum of patients with adult T-cell leukemia/lymphoma (ATL), which is a highly aggressive leukemia/lymphoma caused by human T-cell leukemia virus type 1 (HTLV-1) (Nishioka C, Takemoto S, et al. 2005; Porunkuna R, Takemoto S, et al. 2014). Freshly isolated leukemic cells from acute type ATL patients express little CD30 on the surface, and predominantly produce sCD30 (Pornkuna R, Nishioka C, and Takemoto S. 2014). We here investigated whether plasma sCD30 is associated with risk of ATL in a nested case-control study within a cohort of HTLV-1 carriers (Takemoto S, et al. 2015). We compared sCD30 levels between 11 cases (i.e., HTLV-1 carriers who later progressed to ATL) and 22 age-, sex- and institution-matched control HTLV-1 carriers (i.e., those with no progression). The sIL-2R and sCD30 concentrations at baseline were significantly higher in cases than in controls (P = 0.009 and P<0.001, respectively). In the univariate logistic regression analysis, a higher sIL-2R (≥546.5 U/mL) or sCD30 (≥30.2 U/mL) was significantly associated with ATL development. Among cases, sIL-2R and sCD30 concentrations tended to increase at the time of diagnosis of aggressive-type ATL, but the concentrations were stable in those developing the smoldering-type. High levels of sIL-2R probably down-regulate the proliferative capability of T cells that encounter tumor cells, and proliferating ATL cells are thought to release sCD30, and excess sCD30 may block CD30L on normal activated T cells and myeloid cells, protecting CD30+ ATL cells from apoptosis. Accordingly, high levels of sIL-2R and sCD30 suggest that impaired tumor surveillance leads to the survival of ATL cells. The interleukin (IL)-2 receptor α chain (IL-2Rα, CD25) and CD30 are cell membrane proteins expressed on activated T-cell. High levels of soluble cytokine receptors, soluble IL-2Rα (sIL-2R) and soluble CD30 (sCD30) are detected in the serum of patients with adult T-cell leukemia/lymphoma (ATL), which is a highly aggressive leukemia/lymphoma caused by human T-cell leukemia virus type 1 (HTLV-1) (Nishioka C, Takemoto S, et al. 2005; Porunkuna R, Takemoto S, et al. 2014). Freshly isolated leukemic cells from acute type ATL patients express little CD30 on the surface, and predominantly produce sCD30 (Pornkuna R, Nishioka C, and Takemoto S. 2014). We here investigated whether plasma sCD30 is associated with risk of ATL in a nested case-control study within a cohort of HTLV-1 carriers (Takemoto S, et al. 2015). We compared sCD30 levels between 11 cases (i.e., HTLV-1 carriers who later progressed to ATL) and 22 age-, sex- and institution-matched control HTLV-1 carriers (i.e., those with no progression). The sIL-2R and sCD30 concentrations at baseline were significantly higher in cases than in controls (P = 0.009 and P<0.001, respectively). In the univariate logistic regression analysis, a higher sIL-2R (≥546.5 U/mL) or sCD30 (≥30.2 U/mL) was significantly associated with ATL development. Among cases, sIL-2R and sCD30 concentrations tended to increase at the time of diagnosis of aggressive-type ATL, but the concentrations were stable in those developing the smoldering-type. High levels of sIL-2R probably down-regulate the proliferative capability of T cells that encounter tumor cells, and proliferating ATL cells are thought to release sCD30, and excess sCD30 may block CD30L on normal activated T cells and myeloid cells, protecting CD30+ ATL cells from apoptosis. Accordingly, high levels of sIL-2R and sCD30 suggest that impaired tumor surveillance leads to the survival of ATL cells.

New mouse model of acute adult T-cell leukemia generated by transplantation of AKT, BCLxL, and HBZ-transduced T cells.

Adult T‐cell leukemia/lymphoma (ATL) develops in human T‐cell leukemia virus type 1 (HTLV‐1) carriers. Although the HTLV‐1‐encoded HBZ gene is critically involved, HBZ alone is insufficient and additional, cooperative “hits” are required for the development of ATL. Candidate cooperative hits are being defined, but methods to rapidly explore their roles in ATL development in collaboration with HBZ are lacking. Here, we present a new mouse model of acute type ATL that can be generated rapidly by transplanting in vitro‐induced T cells that have been retrovirally transduced with HBZ and two cooperative genes, BCLxL and AKT, into mice. Co‐transduction of HBZ and BCLxL/AKT allowed these T cells to grow in vitro in the absence of cytokines (Flt3‐ligand and interleukin‐7), which did not occur with any two‐gene combination. Although transplanted T cells were a mixture of cells transduced with different combinations of the genes, tumors that developed in mice were composed of HBZ/BCLxL/AKT triply transduced T cells, showing the synergistic effect of the three genes. The genetic/epigenetic landscape of ATL has only recently been elucidated, and the roles of additional “hits” in ATL pathogenesis remain to be explored. Our model provides a versatile tool to examine the roles of these hits, in collaboration with HBZ, in the development of acute ATL.

Induction of apoptosis by HBI-8000 in adult T-cell leukemia/lymphoma is associated with activation of Bim and NLRP3.

Adult T‐cell leukemia/lymphoma (ATL) is an aggressive T‐cell malignancy caused by human T‐cell lymphotropic virus 1. Treatment options for acute ATL patients include chemotherapy, stem cell transplantation, and recently the anti‐chemokine (C‐C motif) receptor 4 antibody, although most patients still have a poor prognosis and there is a clear need for additional options. HBI‐8000 is a novel oral histone deacetylase inhibitor with proven efficacy for treatment of T‐cell lymphomas that recently received approval in China. In the present study, we evaluated the effects of HBI‐8000 on ATL‐derived cell lines and primary cells obtained from Japanese ATL patients. In most cases HBI‐8000 induced apoptosis in both primary ATL cells and cell lines. In addition, findings obtained with DNA microarray suggested Bim activation and, interestingly, the contribution of the NLR family, pyrin domain containing 3 (NLRP3) inflammasome pathway in HBI‐8000‐induced ATL cell death. Further investigations using siRNAs confirmed that Bim contributes to HBI‐8000‐induced apoptosis. Our results provide a rationale for a clinical investigation of the efficacy of HBI‐8000 in patients with ATL. Although the role of NLRP3 inflammasome activation in ATL cell death remains to be verified, HBI‐8000 may be part of a novel therapeutic strategy for cancer based on the NLRP3 pathway.

Angiotensin II type 1 receptor blocker telmisartan induces apoptosis and autophagy in adult T‐cell leukemia cells

Adult T‐cell leukemia/lymphoma (ATL), an aggressive T‐cell malignancy that develops after long‐term infection with human T‐cell leukemia virus (HTLV‐1), requires new treatments. Drug repositioning, reuse of a drug previously approved for the treatment of another condition to treat ATL, offers the possibility of reduced time and risk. Among clinically available angiotensin II receptor blockers, telmisartan is well known for its unique ability to activate peroxisome proliferator‐activated receptor‐γ, which plays various roles in lipid metabolism, cellular differentiation, and apoptosis. Here, telmisartan reduced cell viability and enhanced apoptotic cells via caspase activation in ex vivo peripheral blood monocytes from asymptomatic HTLV‐1 carriers (ACs) or via caspase‐independent cell death in acute‐type ATL, which has a poor prognosis. Telmisartan also induced significant growth inhibition and apoptosis in leukemia cell lines via caspase activation, whereas other angiotensin II receptor blockers did not induce cell death. Interestingly, telmisartan increased the LC3‐II‐enriched protein fraction, indicating autophagosome accumulation and autophagy. Thus, telmisartan simultaneously caused caspase activation and autophagy. A hypertension medication with antiproliferation effects on primary and leukemia cells is intriguing. Patients with an early diagnosis of ATL are generally monitored until the disease progresses; thus, suppression of progression from AC and indolent ATL to acute ATL is important. Our results suggest that telmisartan is highly effective against primary cells and leukemia cell lines in caspase‐dependent and ‐independent manners, and its clinical use may suppress acute transformation and improve prognosis of patients with this mortal disease. This is the first report demonstrating a cell growth‐inhibitory effect of telmisartan in fresh peripheral blood mononuclear cells from leukemia patients.

Adult T-Cell Leukemia/Lymphoma: A Clinical and Epidemiological Analysis at the Medicine School of Sao Paulo University

Background: Adult T-cell leukemia/lymphoma (ATLL) is a rare disease described in Japan in 1977 and associated with human T-cell leukemia virus 1 (HTLV-1) infection. It is classified into four subgroups [1]: smoldering and chronic forms which are considered indolent and acute and lymphoma subtypes that present an aggressive behavior and short overall survival (OS) despite the treatment. Here, we describe an ATLL experience at a reference cancer treatment institution in Sao Paulo, Brazil.Methods: We retrospectively analyzed 29 ATLL patients who were attended from June/2006 to June/2015 at the Medicine School of Sao Paulo University, Brazil. ATLL was classified according to Shimoyama criteria [1] and Levine score [2] was used to estimate the probability of ATLL diagnosis. All patients were HTLV-1+. In the leukemic subtypes of ATLL, the neoplastic cells were CD3+/CD4+/CD8- or CD3+/CD4-/CD8- along with CD25+ and lack of CD7 expression. In the lymphoma type all patients showed a peripheral T cell lymphoma on their tissue biopsy. Statistical analysis was performed using GraphPad Prism Version 5.0 software.Results: Table 1 shows the clinical characteristics of patients on diagnosis. Acute ATLL was associated with higher Levine's score. The average age on diagnosis was 48.82 years old (18.69-74.26). Our data is in accordance with previous Brazilian studies that showed lower average age on diagnosis. This could be related to earlier infection, intrinsic characteristics of virus strains circulating in Americas or host immune particularities. There was confection with B hepatitis, C hepatitis and HIV in three, two and one case, respectively. Forty-five per cent of the patients had skin lesions and eight patients presented central nervous system disease (4 of acute ATLL). No patient had concomitant HTLV-I-Associated Myelopathy/Tropical Spastic Paraparesis.In our practice, smoldering ATLL was usually held in a watchfull-waiting approach. All six chronic ATLL patients were treated with interferon alpha and zidovudine (IFN+AZT) first-line. Progression-free survival (PFS) was 36.06 months and 12.4 months for smoldering and chronic subtypes, respectively. Acute and lymphoma subtypes had been treated with polichemotherapy, usually with CHOEP regimen (vincristine 1,4 mg/m2 i.v D1, doxorubicin 50mg/m2 i.v D1, cyclophosphamide 750mg/m2 i.v D1, etoposide 750 mg/m2 i.v D1, dexamethasone 20 mg i.v on day 1, prednisone 100 mg days 2 to 5) first-line. Overall average survival for lymphoma ATLL was 11.57 months, shorter than previous reports (average of 16 months, 86% treated with CHOP regimen [3]; survival of 19.7 months LSG15 protocol [4]). Eleven in 15 patients with acute ATLL had died after an average of 8.5 months (2.3 - 15.5) after the diagnosis. Overall survival for all subtypes was 15.17months (fig 1A), and 59.03; 44.47; 11.75 and 5.8 months (p= 0.0634) for smoldering, chronic, lymphoma and acute subtypes, respectively (fig 1B).Conclusion: We found an OS of 5.8 months for acute ATLL treated with chemotherapy as first-line, which is comparable to literature (average survival of 6 months [3]) but shorter than those patients treated with first-line IFN+AZT (average survival of 9 months [3]). In our setting it is still scarcely available trioxide arsenic and clinical trials for ATLL, and allogenic transplant related to mortality is still high. We are therefore changing our practice according to recent recommendations and aiming to treat leukemic ATLL first-line with higher tolerated doses of IFN+AZT to improve our survival curve.

Mogamulizumab Therapy for Adult T-Cell Leukemia-Lymphoma: A Retrospective Multicenter Study

Introduction: Adult T-cell leukemia-lymphoma (ATL) is a peripheral T-cell malignancy, which is caused by human T-cell leukemia virus type I (HTLV-1) and is considered to be derived from regulatory T cells (Treg). ATL is usually resistant to conventional chemotherapies and the patients with ATL have very poor prognosis. Mogamulizumab (Moga) is a humanized monoclonal antibody against CC chemokine receptor 4 (CCR4) which is expressed on T-helper type 2, Treg and tumor cells from most patients with ATL. It was reported that Moga used to treat ATL with 50% efficacy in a phase II study and frequently developed cutaneous adverse reactions (CAR). In that study, development of CAR was reported to be closely associated with the response to Moga therapy. To confirm efficacy and safety of Moga therapy for ATL, we retrospectively analyzed relapsed or refractory ATL patients who were treated by Moga at 4 institutes in Kagoshima, one of the endemic areas of HTLV-1 infection, Southwestern Japan.Patients and methods: There were 77 patients, who were received Moga therapy between March, 2007 (phase I study) and December, 2014. We studied about backgrounds (age, sex, subtypes of ATL, ECOG performance status (PS) at diagnosis and clinical stage) of the patients, contents of prior therapy and the response, prognostic index for acute and lymphoma type ATL (ATL-PI), PS and disease status at Moga therapy, response and adverse events (AE) of Moga therapy, and the survival.Results: Enrolled patients were 44 men and 33 women, and median age at Moga therapy was 65.6 years (range: 44-83 years). They consisted 54 acute, 18 lymphoma, and 5 chronic type ATL, and ATL-PI was low in 18, intermediate in 43 and high in 16 patients. Initial induction chemotherapies were mainly VCAP-AMP-VECP regimen in 41, CHOP like regimen in 19 patients. Median duration between diagnosis and Moga therapy was 8.1 months (range: 0.5-94.9 months). They were administered Moga median 5 cycles (range: 1-10 cycles). Disease status at Moga therapy were 23 relapsed and 54 refractory [partial response (PR): 8, stable disease (SD): 15, progressive disease (PD): 31] disease. Myelosuppression associated with Moga, development of cytomegalovirus antigenemia (19.5%) and other AE were tolerable. Best objective response rate was 42.9% including 18 complete remission (CR) and 15 PR. Fifty-four patients died after Moga therapy (50 from ATL, 4 from infection and so on). Median overall survival (OS) time from Moga therapy was 7.7 months (95%CI: 5.1-11.2 months) and 3-year OS rate was 18.2%. The cohort included 27 patients over 70 years, but their survival was no worse than younger. Twelve patients received allogeneic hematopoietic stem cell transplantation after Moga therapy, but had no survival advantage. Twenty-four patients suffered from CAR, which were developed median 7 cycles (range: 2-8 cycles). The severity of CAR according to CTCAE v3.0 was grade 1 in three, 2 in eight, 3 in eleven and 4 in two patients, respectively. In patients (n = 51) received Moga more than 4 cycles, 22 patients suffered from CAR and their OS (3-year OS: 43.6%) was significantly better than patients without CAR (median OS: 23.4 vs 7.9 months, p = 0.0003).Discussion: Moga therapy is effective and safe for ATL patients and the onset of moderate CAR is a favorable sign of the efficacy. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Molecular Pathology of Adult T-Cell Leukemia/Lymphoma

Adult T-cell leukemia/lymphoma (ATLL) is a peripheral T-cell neoplasm of highly pleomorphic lymphoid cells. ATLL is usually widely disseminated, and it is caused by human T-cell leukemia virus type 1 (HTLV-1). It is a disease with a long latency, and affected individuals are usually exposed to the virus very early in life. The cumulative incidence of ATLL is estimated to be 2.5% among HTLV-1 carriers. ATLL cells express CD2, CD3, CD5, CD4, and CD25, as well as CCR4 and FoxP3 of the regulatory T-cell marker. HTLV-1 is causally linked to ATLL, but infection alone is not sufficient to result in neoplastic transformation. A significant finding in this connection is that the Tax viral protein leads to transcriptional activation of many genes, while the HTLV-1 basic leucine zipper factor is thought to be important for T-cell proliferation and oncogenesis. Half of ATLL cases retain the ability to express HTLV-1 Tax, which is a target of HTLV-1-specific cytotoxic T lymphocytes (CTL). An increase in HTLV-1-specific CTL responses is observed in some asymptomatic HTLV-1 carriers. Although HTLV-1-specific CTL are also present in the peripheral blood of ATLL patients, they do not expand sufficiently. We investigated the clinicopathological features and analyzed the staining of Tax-specific CTL and FoxP3. Tax-specific CTL correlated inversely with FoxP3, an increase in the ratio of CD163+ tumor-associated macrophages was associated with worse clinical prognosis, and ATLL cell lines proliferated significantly following direct co-culture with M2 macrophages. Several clinical variants of ATLL have been identified: acute, lymphomatous, chronic, and smoldering. Oligo-array comparative genomic hybridization revealed that genomic loss of 9p21.3 was a significant characteristic of acute-type, but not of chronic-type ATLL. Furthermore, we found that genomic alteration of CD58, which is implicated in immune escape, is more frequently observed in acute than in chronic ATLL. Interestingly, the chronic cases with cell cycle deregulation and disruption of immunosurveillance mechanism were associated with faster progression to acute ATLL. Immune evasion, microenvironment, and genetic alteration are therefore important in the multi-step progression of ATLL lymphomagenesis.

The HTLV-1 latency-maintenance factor p30II activates p53-dependent metabolic effectors to promote oncogene-activation and aberrant lymphoproliferation

The human T-cell leukemia retrovirus type-1 (HTLV-1) transforms CD4+ T-lymphocytes and causes adult T-cell leukemia/lymphoma (ATLL), an aggressive hematological malignancy that is refractive to most anticancer treatments. The highly-conserved pX sequence of HTLV-1 encodes three latency-maintenance factors: p30II, p13II and Hbz, which suppress proviral gene expression and help HTLV-1-infected cells evade detection by host immune responses as a prelude to neoplastic disease. We have previously demonstrated that p30II enhances the transcriptional and oncogenic functions of the c-Myc oncoprotein and induces aberrant lymphoproliferation through molecular interactions with the TIP60 acetyltransferase. Our recent studies have demonstrated the cooperation between p30II and c-Myc is dependent upon the induction of p53-dependent pro-survival signals. The p30II protein activates p53 and induces expression of p53-dependent metabolic effectors, including the Tp53-induced glycolysis and apoptosis regulator (TIGAR). Acute and lymphoma-stage ATLL clinical isolates frequently over express c-Myc and contain wildtype p53. We therefore hypothesize the induction of p53-dependent pro-survival signals by p30II could promote c-myc oncogene-activation during retroviral carcinogenesis by preventing c-Myc-induced cytotoxicity and apoptosis. Indeed, we have found that lentiviral-p30II induces mitochondrial expression of TIGAR and prevents the intracellular accumulation of c-Myc-induced reactive oxygen species (ROS) and inhibits oncogene-induced cellular senescence. Knockdown of TIGAR expression, using a small-interfering RNA (siRNA-tigar), inhibited the ability of p30II to suppress c-Myc-induced cytotoxicity. A panel of primary ATLL patient tumor lymphocytes exhibited over expression of TIGAR which correlated with c-Myc deregulation, compared to donor hu-PBMCs. Furthermore, we have shown that siRNA-knockdown of TIGAR expression sensitizes HTLV-1-transformed SLB1 lymphoma cells to oncogene-induced ROS and causes cellular senescence, suggesting siRNA-inhibition of TIGAR may be a plausible approach to sensitize ATLL tumor lymphocytes to anticancer chemotherapy drugs that induce oxidative damage. Our studies reveal a paradoxical role for p53-dependent metabolic effectors in promoting oncogene-activation by HTLV-1 p30II, which could promote proviral replication and leukemic disease progression.

Chronic type adult T-cell leukemia-lymphoma after autolougous stem cell transplantation for ALK-negative anaplastic large cell lymphoma

An adult male patient was admitted to our hospital with systemic lymphadenopathy. He was diagnosed as having ALK-negative anaplastic large cell lymphoma (ALCL) by lymph node biopsy. Immunohistochemical staining revealed positive reaction for CD4, CD30, CD25, TIA-1, and Granzyme B, but negative for ALK and EBER. Although anti-HTLV-1 antibody in his serum was positive, monoclonal integration of HTLV-1 provirus DNA was not detected in his lymph node by Southern blot analysis. He was treated by combination chemotherapy, and complete remission was obtained by 8 courses of CHOP therapy. Subsequently he received autologous stem cell transplantation (auto-SCT). Fifteen months after auto-SCT, abnormal lymphocytes in the peripheral blood gradually increased. Southern blot analysis of abnormal lymphocytes revealed monoclonal integration of HTLV-1 provirus DNA and monoclonal rearrangement of T-cell receptor b. The patient was therefore diagnosed as chronic type of adult T-cell leukemia-lymphoma (ATL), and immediately progressed to acute type with central nervous system involvement. He died of tumor progression regardless of intensive chemotherapy. We analyzed genomic alterations of the ALCL cells and the chronic type ATL cells using high-resolution array comparative hybridization. These results revealed that the genomic alteration pattern of ALCL was different from those of the chronic type. Chronic type ATL cells had the genetic alterations such as 1q gain and CD58 loss that were frequently observed in acute type ATL than the chronic type, suggesting that these genetic events might contribute to the transformation of this case. TCR rearrangement analyses using PCR were performed for the tumor cells of ALCL and ATL to evaluate the origin of these tumor cells. Results showed that tumor cell clone of the ATL might have already proliferated in ALCL lymph node. This finding suggests that lymph nodes can serve as a niche for ATL development.

Mutation Analysis for TP53 in Chronic-Type Adult T-Cell Leukemia/Lymphoma.

Adult T-cell leukemia/lymphoma (ATLL) is a T-cell neoplasm caused by human T-cell leukemia virus type I (HTLV-I). ATLL is classified into four clinical subtypes based on the clinical manifestation: acute, lymphoma, chronic and smoldering. Approximately half of chronic type ATLL cases progressed to the acute type. We previously demonstrated that genomic alterations related to the cell cycle de-regulation such as CDKN2A and immune escape such as CD58 alteration can serve as predictive biomarkers for acute transformation of the chronic type. Although alteration of TP53, which is known to be a major regulator of cell cycle, has been identified in several types of cancers including acute type ATLL, no copy number alteration of TP53 was found in the chronic type by array comparative genomic hybridization. In the present study, mutation of TP53 was further analyzed by sequencing for these cases as well as HTLV-I carriers with oligo-clonality. However, no TP53 mutation was identified. These results suggested that TP53 mutation plays a role for the later stage of ATLL development.

Clinical Features and Treatment Outcomes of 81 Patients with Aggressive Type Adult T-cell Leukemia-lymphoma at a Single Institution over a 7-year Period (2006-2012).

Despite the remarkable advances in chemotherapy and allogeneic hematopoietic stem cell transplantation (HSCT), adult T-cell leukemia-lymphoma (ATL) is still associated with a high mortality rate. It is therefore essential to elucidate the current features of ATL. We retrospectively analyzed 81 patients with aggressive type ATL at our institution over a 7-year period based on Shimoyama's diagnostic criteria. Eighty-one patients with a median age of 67.5 years were classified as having acute (n=47), lymphoma (n=32), or chronic type (n=2) ATL. They were initially treated by either palliative therapy (n=25) or systemic chemotherapy [n=56; cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) therapy (n=25)/vincristine, cyclophosphamide, doxorubicin, and prednisone (VCAP)-doxorubicin, ranimustine, and prednisone (AMP)-vindesine, etoposide, carboplatin, and prednisone (VECP) therapy (VCAP-AMP-VECP) or CHOP-VMMV therapy (n=31)], and showed median survival durations of 16 and 277 days, respectively. Subsequent to the initial treatment, HSCT (n=6) was performed for certain patients, thus revealing that two-thirds (n=4) relapsed, and one-third (n=2) survived for 131 days and 203 days, respectively. The relapsed ATL patients were treated with conventional salvage therapy (n=29) or anti-CC chemokine receptor 4 antibody (mogamulizumab) (n=3). The patients treated with mogamulizumab demonstrated complete response (2) and partical response (1) with short duration periods of 82 days, 83 days, and 192 days, respectively. Among the five long-term survivors (>5 years) who received chemotherapy, most showed a low and intermediate risk according to the ATL prognostic index. In our study, the overall survival of ATL remains poor due to the advanced age of the patients at diagnosis, a high proportion of patients receiving palliative therapy, and a small proportion of long-term survivors receiving chemotherapy and undergoing HSCT. This study illustrates the current clinical features, treatment strategies, and outcomes in clinical practice.

Recent Significance of Allogeneic Hematopoietic Stem Cell Transplantation for Adult T Cell Leukemia/Lymphoma (ATL)

Introduction: Adult T cell leukemia/lymphoma (ATL) is a poor prognostic T-cell malignancy and the median survival time of aggressive type ATL is about a year regardless of intensive chemotherapy. Since 2001, several studies mainly from Japan show that allogeneic hematopoietic stem cell transplantation (allo-HSCT) has improved overall survival (OS) of ATL. To confirm the survival of the ATL patients received treatment such as chemotherapy and allo-HSCT and the usefulness of allo-HSCT on ATL, we analyzed retrospectively the patients with ATL treated recently in our institute.Patients and methods: There were total 198 patients who were consecutively hospitalized and received treatments as ATL between July, 2006 and December, 2013 in Imamura Bun-in Hospital that located at Kagoshima, an endemic area of HTLV-1 infection in Japan. This time we studied about backgrounds (age, gender, subtypes of ATL, performance status (PS) at diagnosis and clinical stage) of the patients, content of allo-HSCT, prognostic index for acute and lymphoma type ATL (ATL-PI) and survival duration from diagnosis retrospectively. The comparisons between the mean values were performed by Student’s t test or the Mann–Whitney test. The overall survival from diagnosis (OS) was analyzed with Kaplan-Meir method and Cox regression analysis about OS was performed. Statistical significance defined P<0.05. Statistical analysis ware performed with STATA Version 12 software (Stata Corp).Results: Median age of the patients was 62.5 (range: 32.5-90.5) years old and they were 104 male and 94 female. One hundred forty four patients were initially diagnosed as acute type ATL, 26 as lymphoma type, 18 as chronic type and 10 as smoldering type respectively. ECOG PS at diagnosis was score 0 to 1 in 155 patients (78.3 %) and score 2 to 4 in 43 patients (21.7 %). Clinical stage at diagnosis was stage I to II in 12 patients (6 %) and stage III, IV in others (94 %). Eventually 68 patients received allo-HSCT (allo-bone marrow transplantation in 48, allo-peripheral blood stem cell transplantation in 5 and cord blood transplantation in 15 patients) and all of them were acute and lymphoma type. Fifty-three patients received stem cell from unrelated donors. The median study observation period was 293.5 (range: 7-2539) days. In all 198 patients OS rate at 1 and 3 year were 41.9 % and 17.9 % respectively and 50% OS was 9.8 months and the results were comparable to the past reports. Overall survival rate at 1- and 3-year of the patients who were able to be received allo-HSCT was 54.8 % and 36.5 %, and 50% OS of them was 16.2 months. Overall survival rate at 1- and 3-year of the patients who were not received allo-HSCT and mainly received chemotherapies such as CHOP or VCAP-AMP-VECP regimens was 35.0 % and 7.3 %, and 50% OS was 8.2 months. ATL-PI was reported as a new prognostic prediction tool for patients with acute and lymphoma type ATL, and had prognostic power in acute and lymphoma type ATL who were not received allo-BMT in the present study (1 year OS : 57.2 %, 34.6 % and 18.8 % at low, intermediate and high risk respectively, p<0.000). In the patients received allo-HSCT, there were no patients with high risk of ATL-PI and the patients with low risk were liable to have worse OS than the patients with intermediate risk (1 year OS : 50.4 %, 62.2 % and 3 year OS : 25.7 %, 56.6 % at low and intermediate risk respectively, p=0.114).Conclusions: This retrospective analysis estimates that outcome of chemotherapies for ATL patients were not so improved and allo-HSCT has promising strategy for the patients with ATL who has indication for that. But we reveal that some of patients with low risk of ATL-PI received allo-BMT have poor outcome, these findings should be confirmed in a prospective study. DisclosuresNo relevant conflicts of interest to declare.

Cytotoxic T-Lymphocyte Analysis of Aggressive Types of Adult T-Cell Leukemia/Lymphoma Patients with Complete Remission after Intensive Combination Chemotherapy

Introduction: Adult T-cell leukemia/lymphoma (ATLL) is a peripheral T-cell malignancy caused by human T-lymphotropic virus type I (HTLV-I). Most ATLL cells are CD4 and CCR4 positive, and CD8 negative. ATLL is classified into 4 clinical subtypes: smoldering, chronic, acute, and lymphoma. Acute and lymphoma type ATLLs, which are aggressive types, have a very poor prognosis. In Japan, aggressive ATLLs are commonly treated by intensive chemotherapies, such as VCAP-AMP-VECP, modified LSG15 therapy, and biweekly CHOP therapy. Recently, an anti-CCR4 monoclonal antibody (mogamulizumab) was approved for relapse and refractory ATLL in Japan. Mogamulizumab induces a highly potent antibody dependent cellular cytotoxicity, suggesting the importance of immuno-cell therapy for treatment of ATLL. We report here the extremely interesting results of aggressive ATLL patients with long-term survival and complete remission (CR) after activation of cellular immunity against ATLL cells following intensive chemotherapies.Patients and Methods: We retrospectively evaluated 46 cases of aggressive ATLLs diagnosed at the Nagasaki Genbaku Hospital between January 2001 and August 2011. Of these, 7 patients had long-term survival greater than 3 years with CR after intensive chemotherapies. Four of these 7 patients had human leukocyte antigen (HLA)-A02:01 or HLA-A24:02, and were investigated using anti-HTLV-I specific cytotoxic T-lymphocyte (CTL) analysis. The HTLV-I provirus load in peripheral blood was also analyzed.Results: Table 1 summarizes the characteristics of 7 aggressive type ATLL patients with long-term survival. Four patients were male and 3 were female. Six patients were classified as lymphoma type and 1 as acute type ATLL. The median age was 68 (range, 60–78) years. The median survival period from the onset of the disease was 111 (range, 36–165) months. In all 7 patients, the CD4/CD8 ratio reversed during, or shortly after, chemotherapy and CD8 predominance continued for more than 1 year (range, 13–165 months, median 24 months). Three patients had herpes virus infection during chemotherapy and reversal of the CD4/CD8 ratio appeared just after herpes virus infection in 2 of these patients. These observations suggested that HTLV-I specific CTLs were induced and contributed to the treatment of ATLL in these patients. An HTLV-I specific CTL analysis currently is available in patients with HLA-A02:01 and HLA-A24:02. Three of 7 aggressive ATLL patients with long-term survival and CR had HLA-A02:01 and 1 had HLA-A24:02. Therefore, HTLV-I specific CTL analysis and HTLV-I provirus load in the peripheral blood were performed in all 4 patients. Each patient was examined twice, once in 2012 and once in 2014. HTLV-I specific CTLs were detected in all patients (Table 2 and Figure 1). Although all patients maintained CR for, HTLV-I proviruses were detected in the peripheral blood in all patients (Table 2). This phenomenon was observed both in 2012 and in 2014 (Table 2 and Figure 1).Conclusions: The findings from this study suggest that HTLV-I specific CTLs can be induced in patients with aggressive types of ATLL. In patients having long survival with CR, these CTLs can contribute to treatment and may play a roll inhibiting the relapse of ATLL. The development of efficacious methods to induce HTLV-I specific CTLs in individual ATLL patients may lead to improved outcomes for aggressive types of ATLL.Table 1Summary of aggressive type ATLL patients with long-term survival and complete remissionPatientNo.GenderAge(year)Survival fromthe onset of ATLL (months)Duration ofCD4/CD8 reversal(months)Herpes virus infection1Male69165165+2Male6814096+3Female717165-4Male6012413+5Female6111118-6Male783613-7Female655624-Table 2A Summary of HTLV-I specific CTL analysis and HTLV-I provirus load in the peripheral bloodPatient No.HLA20122014CTLHTLV-I provirusCTLHTLV-I provirus(%)(copies/1000 cells)(%)(copies/1000 cells)1A02:010.1135.40.1361.92A02:010.7824.41.5614.75A02:011.067.11.3113.37A24:022.0726.43.6427.9 [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Using HDAC Inhibitors to Eradicate Adult T-Cell Leukemia-Lymphoma

Adult T-cell leukemia-lymphoma (ATLL) is an aggressive malignancy with a poor prognosis caused by HTLV-I, which is endemic in Japan, the Caribbean, and South America. ATLL cannot be cured with conventional chemotherapy thus urging the development of new therapeutic strategies. Histone deacetyalse (HDAC) inhibitors are broadly active anti-neoplastic agents, which have shown efficacy in T-cell lymphomas. At our institution we encounter a relatively high number of ATLL cases as compared to other regions in the U.S. We have conducted a pilot trial using AZT/interferon-α(IFNα) plus the HDAC inhibitor valproic acid (VPA) during maintenance therapy in acute (leukemia-type) ATLL. We hypothesized that VPA would reactivate HTLV-I leading to a cytotoxic T-cell immune response followed by reduction of residual blood circulating ATLL clones that normally persist during AZT/IFNα therapy despite its suppressive effects. Supporting this notion, the addition of VPA to AZT/IFNα resulted in reduction of HTLV-I proviral loads in treated patients and a sustained molecular response in one subject who is still alive >4.5 years later. More recently, we have tested newly available and more potent HDAC inhibitors using fresh primary leukemic ATLL cells and low-passage cell lines. Through HDAC inhibition, these agents reactivated HTLV-I Tax gene expression and induced apoptosis in a dose-dependent manner. Belinostat, which is currently FDA-approved for the treatment of relapsed or refractory peripheral T-cell lymphoma, augmented ATLL cell death when added to AZT/IFNα at nanomolar concentrations. Therefore, we have proposed a new pilot clinical trial using belinostat for the treatment of ATLL during post-induction therapy. The role of HDAC inhibitors in ATLL, pre-clinical laboratory studies involving these agents, and clinical trial design will be discussed at the meeting DisclosuresOff Label Use: The use of HDAC inhibitors in adult T-cell Leukemia-lymphoma.

Molecular characterization of chronic-type adult T-cell leukemia/lymphoma.

Adult T-cell leukemia/lymphoma (ATL) is a human T-cell leukemia virus type-1-induced neoplasm with four clinical subtypes: acute, lymphoma, chronic, and smoldering. Although the chronic type is regarded as indolent ATL, about half of the cases progress to acute-type ATL. The molecular pathogenesis of acute transformation in chronic-type ATL is only partially understood. In an effort to determine the molecular pathogeneses of ATL, and especially the molecular mechanism of acute transformation, oligo-array comparative genomic hybridization and comprehensive gene expression profiling were applied to 27 and 35 cases of chronic and acute type ATL, respectively. The genomic profile of the chronic type was nearly identical to that of acute-type ATL, although more genomic alterations characteristic of acute-type ATL were observed. Among the genomic alterations frequently observed in acute-type ATL, the loss of CDKN2A, which is involved in cell-cycle deregulation, was especially characteristic of acute-type ATL compared with chronic-type ATL. Furthermore, we found that genomic alteration of CD58, which is implicated in escape from the immunosurveillance mechanism, is more frequently observed in acute-type ATL than in the chronic-type. Interestingly, the chronic-type cases with cell-cycle deregulation and disruption of immunosurveillance mechanism were associated with earlier progression to acute-type ATL. These findings suggested that cell-cycle deregulation and the immune escape mechanism play important roles in acute transformation of the chronic type and indicated that these alterations are good predictive markers for chronic-type ATL.

WS3-3 - Possible Proposal of an Extranodal Primary Gastric Variant of Lymphoma Type Atl

Adult T-cell leukemia-lymphoma (ATL) is a mature T-cell malignancy caused by human T-cell leukemia virus type-I (HTLV-1) and has been classified into four clinical subtypes: acute, lymphoma, chronic, and smoldering. This classification is very useful when deciding on a treatment strategy at the time of diagnosis. Although ATL is generally thought to be a T-cell non-Hodgkin's lymphoma with frequent leukemic manifestations, this classification does not include extranodal lymphoma in ATL. Extranodal ATL in which lesions are located in organs such as the stomach, nasopharhynx, skin and so forth are rare. Although primary gastric ATL is included in the category of acute ATL, we have noted several cases in which the prognosis was much better than is usual with acute ATL. In order to more precisely define primary extranodal ATL, we analyzed patients with primary gastric ATL.The clinicopathological features of six patients (four male, two female; median age 64 years with a range of 46 - 75 years) with localized lesions in the stomach were analyzed and compared. Two patients experienced regional lymph node swelling, and no patients had leukemic manifestations (ATL cells in peripheral blood: ≤ 1%) or hypercalcemia. Serum LDH level was elevated in only one case. Monoclonal integration of HTLV-1 proviral DNA was detected in gastric lesions by Southern blotting in all three cases analyzed. No patients received allo-HSCT. Median overall survival time (OS) after chemotherapy in these six cases was 66 months (3 - 216 months), which is longer than is typically reported for acute type ATL. In conclusion, these cases with localized ATL with relatively good prognosis possibly represent a new clinical subtype of ATL, an extranodal primary gastric variant of the lymphoma type of ATL.This work was supported by a grant (H23-ganrinsho-ippan-022) from the Ministry of Health, Labor and Welfare in Japan.

Adult T‐cell leukaemia/lymphoma can mimic other lymphomas in a non‐endemic area: dilemmas in diagnosis and treatment

The diagnosis of Adult T-cell leukaemia/lymphoma (ATL) in non-endemic regions is challenging. This study analyses the clinicopathologic features and diagnostic processes of ATL patients in Taiwan. ATL patients diagnosed and treated at Taipei Veterans General Hospital from 1998 through 2010 were retrospectively identified. The diagnosis of ATL was confirmed by in situ detection of human T-cell leukaemia virus type 1 (HTLV-1) when necessary. Patients' data were reviewed and analysed. Fourteen ATL patients were identified, among whom six (42.9%) had an antecedent diagnosis of other malignant lymphomas before the ATL diagnosis, including two diagnosed with Hodgkin disease (HD), one with peripheral T-cell lymphoma, two with chronic lymphocytic leukaemia and one with angioimmunoblastic T-cell lymphoma. Of the 14 patients, eight (57%) were subclassified as the acute type, three (21.4%) as the lymphoma type, and three (21.4%) as the chronic type ATL. Five of six (83.3%) patients with initial non-ATL misdiagnosis were diagnosed with non-acute type ATL. In particular, a patient with an antecedent diagnosis of HD presented with typical Reed-Sternberg (RS)-like cells harbouring Epstein-Barr virus genomes in affected lymph nodes. The patient progressed to acute type ATL 3 years after the initial diagnosis, and HTLV-1 genomes were identified in the previous RS-like cells. In non-endemic areas, such as Taiwan, ATL, particularly the non-acute type, may mimic other lymphomas and easily be misdiagnosed. HTLV-1 serology should be routinely screened in all malignant lymphoma patients. In situ detection of HTLV-1 is helpful in cases with diagnostic dilemmas.

What is the Role of Soluble Cytokine Receptors in Adult T-cell Leukemia/ Lymphoma?

Soluble cytokine receptors are products of tumor cells infected with viruses such as human T-cell leukemia virus type 1 (HTLV-1). Adult T-cell leukemia/lymphoma (ATLL) is a highly aggressive leukemia/lymphoma caused by HTLV-1. High levels of soluble cytokine receptors are detected in the serum of patients with ATLL. Matrix metalloproteinase (MMP)-9 cleaves the interleukin (IL)-2 receptor α chain (IL-2Rα, CD25), which produces soluble IL-2Rα (sIL-2R) and down-regulates the proliferative capability of T cells that encounter cancer cells. Soluble CD30 (sCD30) impairs the interaction of CD30 ligand+ cells with CD30+ cells, whereas CD30 expression integrates survival signals to NK cells. Accordingly, high level of sIL-2R and sCD30 suggest that not only does impaired tumor surveillance lead to the survival of ATLL cells, but also dysfunction of immune surveillance can cause severe infectious complications. Freshly isolated leukemic cells from acute type ATLL patients express little CD30 on the surface, and predominantly produce sCD30. Proliferating ATLL cells are thought to release sCD30, and excess sCD30 probably blocks CD30L on normal activated T cells and myeloid cells, protecting CD30+ ATLL cells from apoptosis. Regarding CD30, two types of MMPs have been reported, ADAM10 and ADAM17, and Tax expression may be associated with ADAM17 activation in HTLV-1-infected cells. Thus, soluble cytokine receptor, sCD30, is both a serum component and a functional protein. Detection of sCD30 level may be useful for detecting and monitoring Tax-expressing tumor cells in vivo.