Adult T Cell Leukemia/Lymphoma (ATLL) Is a Malignant Counterpart of Regulatory T Cells (Treg).

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 82-82
Author(s):  
Tomoko Kohno ◽  
Yasuaki Yamada ◽  
Norihiko Akamatsu ◽  
Shimeru Kamihira ◽  
Masao Tomonaga ◽  
...  

Abstract Adult T cell leukemia/lymphoma (ATLL) is a lymphoproliferative disorder caused by a retrovirus, human T-lymphotropic virus type 1 (HTLV-1). ATLL is subclassified into four subtypes, smoldering, chronic, acute, and lymphoma. The acute type progresses rapidly and is usually resistant to conventional chemotherapy. In contrast, the chronic type shows an indolent clinical course and the patients survive for several years, even without chemotherapy. Irrespective of the subtypes, however, ATLL patients are in a severely immune-suppressed condition and can easily acquire opportunistic infections such as Pneumocystis Carinii pneumonitis. Suppression of cell-mediated immunity has also been reported in HTLV-1 carriers. Although ATLL cells show the activated helper/inducer T-cell phenotypes, CD4+ and CD25+, they exhibit strong immune-suppressive activity in vitro. The recent notion of CD4+ CD25+ regulatory T cells (Treg) prompted us to investigate the origin of ATLL cells from the standpoint of Treg. Forkhead/winged helix transcription factor (Foxp3) is a functional marker of Treg, which plays a central role in their generation. There are other marker molecules for Treg, including glucocorticoid-induced TNFR family-related protein (GITR) and the chemokine receptors CCR4 and CCR8. In the present study, we examined primary ATLL cells from 48 patients: 36 patients with acute type and 12 patients with chronic type. We also examined ATLL cell lines, HTLV-1-infected T-cell lines and peripheral blood mononuclear cells (PBMC) from healthy adults as control cells. We used RT-PCR for detection of Foxp3, GITR, CCR4, and CCR8 mRNA expression. Foxp3 and/or GITR mRNA were detected in over 90% of the patients, and 50% of the patients expressed both. There was no difference between subtypes. In contrast, Foxp3 and GITR mRNA were scarcely detected in the PBMC from healthy adults. Furthermore, we confirmed GITR expression at the protein level by flow cytometry. CCR4 and CCR8 mRNA were also detected in almost all ATLL samples, at significantly higher levels than in the normal PBMC. Corresponding to the results of the primary cells, ATLL cell lines and HTLV-1-infected T-cell lines also expressed GITR mRNA, although HTLV-1-negative cell lines, Jurkat and Molt4, completely lack it. Next, we examined whether GITR affects ATLL cell proliferation using a GITR- expressing IL-2-dependent ATLL cell line, KK1. We found that GITR ligand induced proliferation of KK1 cells in an IL-2-negative condition. Thus, these results indicate the Treg origin of ATLL cells and show that GITR expression is possibly involved in the development of ATLL.

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 845-845
Author(s):  
Noriaki Yoshida ◽  
Kennosuke Karube ◽  
Atae Utsunomiya ◽  
Kunihiro Tsukasaki ◽  
Yoshitaka Imaizumi ◽  
...  

Abstract Introduction 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 chronic and smoldering subtypes are regarded as indolent ATL, about half of these cases progress to acute type ATL and subsequent death. Therefore, cases of indolent ATL also have poor prognosis and acute transformation is a predictive indicator for patients with indolent ATL. However, the molecular pathogenesis of acute transformation remains unknown. In the present study, oligo-array comparative genomic hybridization (CGH) and comprehensive gene-expression profiling (GEP) were applied to 27 and 35 cases of chronic and acute type ATL, respectively, in an effort to delineate the molecular pathogeneses of ATL, and especially the molecular mechanism of acute transformation. Materials and Methods All DNA and RNA used in this study were extracted from purified CD4-positive cells. Oligo-array CGH analyses and comprehensive GEP analyses were performed on 27 and 35 cases of chronic and acute type ATL, respectively. Subsequently, we established Tet-OFF ATL cell lines for functional analyses. Results Oligo-array CGH revealed that genomic loss of 9p21.3 was significantly characteristic of acute type ATL, but not chronic type ATL (p-value= 0.039). Although the minimal common deleted region of 9p21.3 contained MTAP, CDKN2A and CDKN2B, the expression level of only CDKN2A was reduced with genomic loss of 9p21.3 (Figure 1). Moreover, analysis of serial samples of a chronic type ATL patient showing acute transformation also revealed that reduction of CDKN2A expression by 9p21.3 loss was associated with acute transformation in this case. CDKN2A contains two known variants, INK4a and ARF. Re-expression of INK4a and ARF suppressed proliferation of Tet-OFF ATL cell lines, while the suppression efficiency of INK4a was stronger than that of ARF (Figure 2). In cell-cycle assays, the induction of INK4a and ARF decreased the proportion of S-phase cells. Additionally, re-expression of INK4a also increased the amount of apoptotic cells in induced cell lines, while re-expression of ARF did not have this effect. Since CDKN2A is a well-known cell cycle regulator, deregulation of the cell-cycle might be involved in acute transformation of chronic type ATL. In fact, deregulation of the cell-cycle pathway has been reported as a predictive indicator for the outcome in diffuse large B-cell lymphoma patients (Cancer Cell, 22:359-372). Therefore, we examined whether chronic ATL patients had alterations in cell-cycle related genes and found that chronic ATL patients could be divided into two groups. The group possessing alterations in these genes (referred to as “Cell cycle Alteration”) showed poorer prognosis compared with the group lacking such alterations (referred to as “Clean”) (p-value= 0.037) (Figure 3). Additionally, patients with such alterations tended to have earlier progression to acute type ATL. Conclusion These findings indicated that cell cycle-related genes play an important role in acute transformation and should serve as good prognostic markers for chronic type ATL. Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 3959-3959
Author(s):  
Daisuke Sasaki ◽  
Yoshitaka Imaizumi ◽  
Hiroo Hasegawa ◽  
Akemi Osaka ◽  
Kazuto Tsuruda ◽  
...  

Abstract Abstract 3959 Poster Board III-895 Background Enhancer of zeste homologue 2 (EZH2) is a critical component of the Polycomb Repressive Complexes PRC2, which mediates epigenetic gene silencing by the trimethylation of Lys27 of histone 3 (H3K27). This regulation is not only involved in embryonic development and stem cell renewal, but also in tumor progression. Adult T-cell leukemia/lymphoma (ATLL) is a single disease entity etiologically associated with human T-cell leukemia virus type-1 (HTLV-1). Its clinical behavior, however, is quite diverse among patients and is thus subclassified into several subtypes. The prognosis of the aggressive subtypes is very poor based on standard chemotherapy, and so the development of a new therapeutic approach is urgent. Results In a comparative microarray analysis of primary ATLL samples, the acute type showed significantly higher EZH2, YY1, and RYBP (RING1 and YY1 binding protein) expressions compared with the chronic type. Further analysis employing real-time quantitative RT-PCR of various Polycomb group (PcG)-related proteins, including the ones mentioned above, revealed that the mRNAs of two other PRC2 components, EED and RBBP4, were also significantly elevated in ATLL, irrespective of the subtypes, compared with lymphocytes from HTLV-1 carriers. These results suggest that the dysregulation of PRC2 is a key event in the development and progression of ATLL. In the immunohistochemical analysis of ATLL lymph nodes, the nuclei of over 90% of ATLL cells were positive for EZH2, which in clear contrast to reactive or indolent B-lymphoma lymph nodes in which a few cells were positive. It has been shown that activated Akt phosphorylates EZH2 at serine 21 and suppresses its methyltransferase activity. Western blotting of EZH2 showed that EZH2 of primary ATLL cells was not phospholyrated and remained in its active form. Indeed, the trimethylation of H3K27 in ATLL cells was confirmed by Western blotting and immunohistochemistry, whereas it was completely absent in lymphocytes from HTLV-1 carriers. Finally, in studies using ATLL cell lines, the knockdown of EZH2 by siRNA caused decrease in cell proliferation. Moreover, ATLL cell lines showed high sensitivities to histone deacetylase (HDAC) inhibitors as LBH589, and LBH589 decreased EZH2 expression. EZH2 inhibitor 3-deazaneplancin A (DZNeP) also reduced cell growth, not only in primary ATLL cells, but also in ATLL cells lines. These results strongly support the rationale for developing molecular targeting therapies against EZH2 in ATLL. Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
1983 ◽  
Vol 61 (5) ◽  
pp. 1014-1016
Author(s):  
M Tsudo ◽  
T Uchiyama ◽  
H Uchino ◽  
J Yodoi

Anti-Tac monoclonal antibody, which blocks the membrane binding and action of human T-cell growth factor (TCGF), is strongly proposed to recognize TCGF receptor. We have demonstrated that anti-Tac antibody reacted with leukemic cells from patients with adult T-cell leukemia (ATL) and reacted with T-cell lines established from ATL cells. Although antigenic modulation, or down-regulation, of Tac antigen on activated normal T cells was induced by anti-Tac antibody, the expression of Tac antigen on ATL cells or T-cell lines was not affected when examined by the fluorescence-activated cell sorter (FACS) and the radioassay using 125I-staphylococcal protein A. These results indicate that regulation of Tac antigen-TCGF receptor is different between normal and malignant T cells, suggesting that failure of down- regulation of Tac antigen on leukemic cells by anti-Tac antibody may play an important role in the malignant proliferation of ATL cells.


Blood ◽  
1983 ◽  
Vol 61 (5) ◽  
pp. 1014-1016 ◽  
Author(s):  
M Tsudo ◽  
T Uchiyama ◽  
H Uchino ◽  
J Yodoi

Abstract Anti-Tac monoclonal antibody, which blocks the membrane binding and action of human T-cell growth factor (TCGF), is strongly proposed to recognize TCGF receptor. We have demonstrated that anti-Tac antibody reacted with leukemic cells from patients with adult T-cell leukemia (ATL) and reacted with T-cell lines established from ATL cells. Although antigenic modulation, or down-regulation, of Tac antigen on activated normal T cells was induced by anti-Tac antibody, the expression of Tac antigen on ATL cells or T-cell lines was not affected when examined by the fluorescence-activated cell sorter (FACS) and the radioassay using 125I-staphylococcal protein A. These results indicate that regulation of Tac antigen-TCGF receptor is different between normal and malignant T cells, suggesting that failure of down- regulation of Tac antigen on leukemic cells by anti-Tac antibody may play an important role in the malignant proliferation of ATL cells.


2008 ◽  
Vol 82 (8) ◽  
pp. 3843-3852 ◽  
Author(s):  
Masanori Baba ◽  
Mika Okamoto ◽  
Takayuki Hamasaki ◽  
Sawako Horai ◽  
Xin Wang ◽  
...  

ABSTRACT Human T-lymphotropic virus type 1 (HTLV-1) is the etiologic agent of adult T-cell leukemia (ATL). In Japan, the number of HTLV-1 carriers is estimated to be 1.2 million and more than 700 cases of ATL have been diagnosed every year. Considering the poor prognosis and lack of curative therapy of ATL, it seems mandatory to establish an effective strategy for the treatment of ATL. In this study, we attempted to identify the cell surface molecules that will become suitable targets of antibodies for anti-ATL therapy. The expression levels of approximately 40,000 host genes of three human T-cell lines carrying HTLV-1 genomes were analyzed by oligonucleotide microarray and compared with the expression levels of the genes in an HTLV-1-negative T-cell line. The HTLV-1-carrying T-cell lines used for experiments had totally different expression patterns of viral genome. Among the genes evaluated, the expression levels of 108 genes were found to be enhanced more than 10-fold in all of the T-cell lines examined and 11 of the 108 genes were considered to generate the proteins expressed on the cell surface. In particular, the CD70 gene was upregulated more than 1,000-fold and the enhanced expression of the CD70 molecule was confirmed by laser flow cytometry for various HTLV-1-carrying T-cell lines and primary CD4+ T cells isolated from acute-type ATL patients. Such expression was not observed for primary CD4+ T cells isolated from healthy donors. Since CD70 expression is strictly restricted in normal tissues, such as highly activated T and B cells, CD70 appears to be a potential target for effective antibody therapy against ATL.


1997 ◽  
Vol 21 (3) ◽  
pp. 211-216 ◽  
Author(s):  
Kakushi Matsushita ◽  
Naomichi Arima ◽  
Hideo Ohtsubo ◽  
Hiroshi Fujiwara ◽  
Shiroh Hidaka ◽  
...  

2005 ◽  
Vol 96 (8) ◽  
pp. 527-533 ◽  
Author(s):  
Tomoko Kohno ◽  
Yasuaki Yamada ◽  
Norihiko Akamatsu ◽  
Simeru Kamihira ◽  
Yoshitaka Imaizumi ◽  
...  

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 3255-3255
Author(s):  
Kennosuke Karube ◽  
Koichi Ohshima ◽  
Junji Suzumiya ◽  
Mine Harada ◽  
Masahiro Kikuchi

Abstract AIMES: Adult T cell leukemia/lymphoma (ATLL) is an aggressive neoplastic disease and opportunistic infections often occur in patients with ATLL. However, the underlying mechanisms of such infections remain unknown. Recently, regulatory T cells (Treg), characterized by coexpression of CD4 and CD25, are proposed as a new T cell group with definite function. Treg suppresses normal T cells proliferation in vitro and play an important role to suppress autoimmune disease in vivo. But the deregulated proliferation such immunosuppressive T cells may induce immunodeficient status. We analyzed the expression of forkhead/winged helix transcription factor (FoxP3), known to be important for the function and specific marker of Treg cells, on ATLL cells. METHODS and RESULTS: FoxP3 expression was detected in both peripheral blood and lymph nodes in part of ATLL cases by real-time PCR and immunostaining (Figure). Next, we immunostained lymph node sections from 112 cases and 36 cases showed positivity for FoXP3. Morphologically, 112 ATLL cases were divided into three variants, namely pleomorphic cell type (61 cases), large cell type (45 cases), and anaplastic large cell type (16 cases). FoxP3 was expressed (more than 30% of the lymphoma cells) in a proportion of pleomorphic cell type (24 cases, 39.4%) and large cell type (12 cases, 26.7%) but no cases of anaplastic type showed positivity. Especially, strong expression (more than 50% of the lymphoma cells) was observed in 15 cases and 12 cases were pleomorphic cell type (Table). A proportion of FoxP3 positive ATLL cases showed intermingled EBV-infected transformed lymphocytes, suggesting local immunodeficient condition (Very few FoxP3 negative cases showed EBV-infected lymphocytes)(Table). Clinically, more proportion of FoxP3 positive ATLL cases showed opportunistic infection, for example Pneumocystis Carinii infections, Herpes zoster virus infection, antibiotics-refractory abscesses (Table). CONCLUSION: A proliferation of FoxP3 positive lymphoma cells may contribute to the tumor invasion and opportunistic infection by inducing local and diffuse immunodeficient status respectively. Figure Figure


Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 2525-2525
Author(s):  
Tetsuro Nakazato ◽  
Chie Ishikawa ◽  
Taeko Okudaira ◽  
Mariko Tomita ◽  
Naoki Mori

Abstract Adult T-cell leukemia (ATL) is caused by human T-cell leukemia virus type I (HTLV-I) and remains incurable. Retinoid is a collective term for compounds, which bind to and activate retinoic acid receptors (RARα, β, γ and RXRα, β, γ), members of nuclear hormone receptor superfamily. It is involved in cell differentiation, morphogenesis, proliferation, and anti-neoplastic processes. The most important endogenous retinoid is all-trans-retinoic acid (ATRA), which is an RARα, β, and γ ligand. ATRA and its mimics have been in clinical use for treatment of acute promyelocytic leukemia (APL) and adult T-cell leukemia (ATL). Many synthetic retinoids have been developed and attempts to improve their medicinal properties have been made. Among them, a novel synthetic retinoid, Am80 (Tamibarotene) is an RARα- and RARβ-specific (but RARγ- and RXRs-nonbinding) synthetic retinoid that is expected to overcome ATRA resistance, because of several times more potent differentiation activity than ATRA and sustained plasma level during continuous administration due to a lower affinity for cellular retinoic acid binding protein. On this background, we examined the inhibitory effect of Am80 on HTLV-I-infected T-cell lines and primary ATL cells. Am80 showed little growth inhibition of peripheral blood mononuclear cells, but it markedly inhibited the growth of both HTLV-I-infected T-cell lines and primary ATL cells. Am 80 could arrest cells in the G1 phase of the cell cycle and induced apoptosis in HTLV-I-infected T-cell lines. The NF-κB pathway is critical for the immortalization and survival of HTLV-I-infected T cells. Therefore, NF-κB pathway was examined as potential targets of Am80 signaling. Am80 significantly inhibited phosphorylation of IκBα and NF-κB-DNA binding, in conjunction with the reduction of expression of proteins involved in the G1-S cell cycle transition and apoptosis. Furthermore, in animal studies, treatment with Am80 produced partial inhibition of growth of tumors of an HTLV-I-infected T-cell line transplanted subcutaneously in severe combined immunodeficient mice. These findings clearly demonstrate that Am80 is a potential inhibitor of NF-κB in ATL cells, and might be a useful therapeutic agent against ATL.


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