Suppression of Cell Growth and Induction of Apoptosis of HTLV-I-Infected T-Cell Lines and Primary ATL Cells by Galectin-9.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 4810-4810
Author(s):  
Taeko Okudaira ◽  
Mariko Tomita ◽  
Mitsuomi Hirashima ◽  
Naoki Mori
Keyword(s):  
T Cell ◽  
Cell Growth ◽  
Cell Lines ◽  
Cyclin B1 ◽  
Type I ◽  
T Cell Leukemia ◽  
Cell Leukemia ◽  
Cell Leukemia Virus Type ◽  
Galectin 3 ◽  
T Cell Lines

Abstract Adult T-cell leukemia (ATL) is a fatal malignancy of T lymphocytes caused by infection with human T-cell leukemia virus type I (HTLV-I), and remains incurable. Therefore, novel treatments are urgently needed. Galectins are a family of animal lectins with diverse biological activities. They function both extracellularly, by interacting with cell-surface and extracellular matrix glycoproteins and glycolipids, and intracellularly, by interacting with cytoplasmic and nuclear proteins to modulate signaling pathways. The distribution of galectins is quite diverse, and their expression in various leukocytes has been observed. To determine whether expression of galectins in T cells correlates with HTLV-I infection, we surveyed a number of uninfected and HTLV-I-infected T-cell lines for galectin-3, -8, and -9 expression by RT-PCR. Expression of galectin-8 did not correlate with HTLV-I infection. Galectin-3 was abundantly expressed in HTLV-I-infected T-cell lines and primary ATL cells, but not in uninfected T-cell lines. In contrast, galectin-9 was abundantly expressed in uninfected T-cell lines and normal PBMCs, but not in HTLV-I-infected T-cell lines and primary ATL cells. HTLV-I transformed protein, Tax, did not affect the expression of galectin-3 and -9. It was previously shown that galectin-8 and -9 are proapoptotic proteins. We found that galectin-9 prevented cell growth of HTLV-I-infected T-cell lines and primary ATL cells compared with galectin-8. Galectin-9 induced cell cycle arrest by reducing the expression of cyclin D1, cyclin D2, cyclin B1, Cdk1, Cdk4, Cdk6, and Cdc25C, and apoptosis by reducing the expression of XIAP and c-IAP2. Most of these genes are known to be regulated by NF-κB, which plays a critical role in oncogenesis by HTLV-I. Galectin-9 suppressed phosphorylation of IκBα. Most importantly, treatment with galectin-9 reduced tumor formation from an HTLV-I-infected T-cell line, HUT-102, when these cells were inoculated s.c. into severe combined immunodeficient mice. Our results suggest that galectin-9 may be a new approach for management of ATL.

Human T-Cell Leukemia Virus Type I Tax Activates CD69 Gene Expression.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 2256-2256
Author(s):  
Chie Ishikawa ◽  
Taeko Okudaira ◽  
Tetsuro Nakazato ◽  
Mariko Tomita ◽  
Naoki Mori
Keyword(s):  
T Cell ◽  
Cell Lines ◽  
Leukemia Virus ◽  
Type I ◽  
T Cell Leukemia ◽  
Cell Leukemia ◽  
Cell Leukemia Virus Type ◽  
Human T Cell ◽  
Cd69 Expression ◽  
T Cell Lines

Abstract The human T-cell leukemia virus type I (HTLV-I) is an oncogenic retrovirus that is etiologically linked to the genesis of adult T-cell leukemia (ATL). Emerging evidence suggests that the pathogenicity of ATL involves suppression of the overall immune response, although the underlying mechanism remains unclear. In this study, we demonstrated that HTLV-I transactivator Tax induces the aberrant expression of CD69, an early leukocyte activation molecule that plays an important role in downregulation of the immune response. In a panel of HTLV-I-infected T-cell lines, CD69 expression was highly elevated compared to HTLV-I-negative T-cell lines at both mRNA and protein levels. Furthermore, CD69 expression correlated with Tax expression. Peripheral blood mononuclear cells from ATL patients also showed an increased expression of CD69 compared with controls. In vitro infection of a T-cell line with HTLV-I was associated with CD69 expression in conjunction with the increasing Tax expression. Expression of CD69 was dependent upon Tax expression in the inducible Tax-expressing cell line JPX-9. Tax transactivated the CD69 gene promoter in a transient transfection assay. Using Tax mutants and dominant negative mutants of IκBs, IKKs, NIK, and CREB, we demonstrated that Tax-induced CD69 expression required the NF-κB and CREB signaling pathways. A series of deletion and mutation analyses of the CD69 gene promoter indicated that two NF-κB, two EGR, and a CRE sequences were critical for Tax transactivation. Electrophoretic mobility shift assay showed the formation of specific protein-DNA complexes in HTLV-I-infected T-cell lines. These results suggest that Tax directly transactivated CD69 gene expression, through multiple cis-acting elements and by the interplay of transcription factors of the NF-κB, EGR, and CREB families. Tax-induced CD69 expression may be involved in immune suppression in ATL.

scholarly journals Transcriptional regulation of the human interleukin-6 gene promoter in human T-cell leukemia virus type I-infected T-cell lines: evidence for the involvement of NF-kappa B

Blood ◽  
1994 ◽  
Vol 84 (9) ◽  
pp. 2904-2911 ◽  
Author(s):  
N Mori ◽  
F Shirakawa ◽  
H Shimizu ◽  
S Murakami ◽  
S Oda ◽  
...  
Keyword(s):  
T Cell ◽  
Cell Lines ◽  
Leukemia Virus ◽  
Type I ◽  
T Cell Leukemia ◽  
Cell Leukemia ◽  
Nf Kappa B ◽  
Cell Leukemia Virus Type ◽  
Human T Cell ◽  
T Cell Lines

Abstract Freshly isolated leukemic cells from patients with adult T-cell leukemia (ATL) and human T-cell leukemia virus type I (HTLV-I)-infected T-cell lines constitutively produce high levels of interleukin-6 (IL-6) protein and mRNA. To clarify the mechanisms that lead to the activation of IL-6 gene in HTLV-I-infected cells, we first studied the regulatory regions in the IL-6 gene transcription by transfection of chloramphenicol acetyltransferase (CAT) reporter plasmids containing the IL-6 promoter. When transfected into HTLV-I-infected T-cell lines MT-2 and HUT-102, IL-6 promoter/CAT plasmids were strongly activated without any stimulation. By deletion analysis of 52 upstream region of IL-6 promoter, the DNA region between -73 and -59 bp from the transcription start site of IL-6 gene was important in the expression of IL-6/CAT activities in HTLV-I-infected cells. This region contains nuclear factor (NF)-kappa B binding site. The site-directed mutation of the kappa B motif in IL-6/CAT plasmid resulted in the complete abrogation of IL-6 promoter activity in these cells. Furthermore, when IL-6 promoter/CAT plasmid was introduced into an HTLV-I-uninfected T- cell line, Jurkat, IL-6 promoter activity was silent in the basal level, but strongly increased by the cotransfection with an HTLV-I tax expression plasmid. However, tax expression plasmid showed no transactivation activity, when kappa B site was mutated in IL-6 promoter/CAT plasmid. We found that the IL-6 kappa B site specifically formed a complex with NF-kappa B-containing nuclear extracts from MT-2 and HUT-102 cells. Finally, transfection of HTLV-I tax into Jurkat cells resulted in induction of specific binding of nuclear extracts to the NF-kappa B sequence. These results strongly suggest that HTLV-I tax gene may transactivate IL-6 gene through kappa B site in HTLV-I- positive T-cell lines and activation of NF-kappa B may be crucial in HTLV-I-induced IL-6 gene activation in ATL.

scholarly journals Retracted: A modified version of galectin-9 suppresses cell growth and induces apoptosis of human T-cell leukemia virus type I-infected T-cell lines

2007 ◽  
Vol 120 (10) ◽  
pp. 2251-2261 ◽  
Author(s):  
Taeko Okudaira ◽  
Mitsuomi Hirashima ◽  
Chie Ishikawa ◽  
Shoko Makishi ◽  
Mariko Tomita ◽  
...  
Keyword(s):  
T Cell ◽  
Cell Growth ◽  
Cell Lines ◽  
Leukemia Virus ◽  
Type I ◽  
Cell Leukemia ◽  
Cell Leukemia Virus Type ◽  
Human T Cell ◽  
T Cell Leukemia Virus ◽  
T Cell Lines

scholarly journals Transcriptional regulation of the human interleukin-6 gene promoter in human T-cell leukemia virus type I-infected T-cell lines: evidence for the involvement of NF-kappa B

Blood ◽  
1994 ◽  
Vol 84 (9) ◽  
pp. 2904-2911 ◽  
Author(s):  
N Mori ◽  
F Shirakawa ◽  
H Shimizu ◽  
S Murakami ◽  
S Oda ◽  
...  
Keyword(s):  
T Cell ◽  
Cell Lines ◽  
Leukemia Virus ◽  
Type I ◽  
T Cell Leukemia ◽  
Cell Leukemia ◽  
Nf Kappa B ◽  
Cell Leukemia Virus Type ◽  
Human T Cell ◽  
T Cell Lines

Freshly isolated leukemic cells from patients with adult T-cell leukemia (ATL) and human T-cell leukemia virus type I (HTLV-I)-infected T-cell lines constitutively produce high levels of interleukin-6 (IL-6) protein and mRNA. To clarify the mechanisms that lead to the activation of IL-6 gene in HTLV-I-infected cells, we first studied the regulatory regions in the IL-6 gene transcription by transfection of chloramphenicol acetyltransferase (CAT) reporter plasmids containing the IL-6 promoter. When transfected into HTLV-I-infected T-cell lines MT-2 and HUT-102, IL-6 promoter/CAT plasmids were strongly activated without any stimulation. By deletion analysis of 52 upstream region of IL-6 promoter, the DNA region between -73 and -59 bp from the transcription start site of IL-6 gene was important in the expression of IL-6/CAT activities in HTLV-I-infected cells. This region contains nuclear factor (NF)-kappa B binding site. The site-directed mutation of the kappa B motif in IL-6/CAT plasmid resulted in the complete abrogation of IL-6 promoter activity in these cells. Furthermore, when IL-6 promoter/CAT plasmid was introduced into an HTLV-I-uninfected T- cell line, Jurkat, IL-6 promoter activity was silent in the basal level, but strongly increased by the cotransfection with an HTLV-I tax expression plasmid. However, tax expression plasmid showed no transactivation activity, when kappa B site was mutated in IL-6 promoter/CAT plasmid. We found that the IL-6 kappa B site specifically formed a complex with NF-kappa B-containing nuclear extracts from MT-2 and HUT-102 cells. Finally, transfection of HTLV-I tax into Jurkat cells resulted in induction of specific binding of nuclear extracts to the NF-kappa B sequence. These results strongly suggest that HTLV-I tax gene may transactivate IL-6 gene through kappa B site in HTLV-I- positive T-cell lines and activation of NF-kappa B may be crucial in HTLV-I-induced IL-6 gene activation in ATL.

The Bisphosphonate, Incadronate, Inhibits Cell Growth of HTLV-I-Infected T-Cell Lines and Primary ATL Cells by Inhibiting Mevalonate Pathway.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 4809-4809
Author(s):  
Chie Ishikawa ◽  
Taeko Okudaira ◽  
Mariko Tomita ◽  
Naoki Mori
Keyword(s):  
T Cell ◽  
Cell Growth ◽  
Cell Lines ◽  
Mevalonate Pathway ◽  
Growth Suppression ◽  
Phase Cell ◽  
Type I ◽  
T Cell Leukemia ◽  
Cell Leukemia ◽  
T Cell Lines

Abstract Bisphosphonates have been used for the treatment of hypercalcemia associated with malignancies and osteoporosis. Recent reports have suggested that bisphosphonates may also exert direct antitumor effects on several cancers, in addition to their therapeutic antiresorptive properties. Adult T-cell leukemia (ATL) is a fatal malignancy of T lymphocytes caused by infection with human T-cell leukemia virus type I (HTLV-I), and remains incurable. ATL is associated with osteolytic bone lesions and hypercalcemia, which are major factors in the morbidity of ATL. Therefore, the search for anti-ATL agents that have antitumor and antiresorptive effects is warranted. The aim of this study was to determine the effect of bisphosphonate, incadronate, on HTLV-I-infected T-cell lines and primary ATL cells. Incadronate prevented cell growth of HTLV-I-infected T-cell lines and primary ATL cells, but not of uninfected T-cell lines and normal PBMCs. Incadronate induced S-phase cell cycle arrest and apoptosis in HTLV-I-infected T-cell lines. Treatment of HTLV-I-infected T-cell lines with cell-permeable substrates for mevalonate pathways, geranylgeraniol and farnesol, prevented incadronate-mediated growth suppression. Incadronate also prevented the prenylation of Ras proteins. These results demonstrate that incadronate-induced growth suppression is the result of inhibition of the mevalonate pathway. On the other hand, incadronate did not affect NF-κB and AP-1 pathways. Importantly, treatment with incadronate reduced tumor formation from an HTLV-I-infected T-cell line, HUT-102, when these cells were inoculated s.c. into severe combined immunodeficient mice. These findings indicate that incadronate may become a novel molecular therapeutic class for treatment of ATL.

Expression of Human Inducible Nitric Oxide Synthase Gene in T-Cell Lines Infected With Human T-Cell Leukemia Virus Type-I and Primary Adult T-Cell Leukemia Cells

Blood ◽  
1999 ◽  
Vol 94 (8) ◽  
pp. 2862-2870 ◽  
Author(s):  
Naoki Mori ◽  
Youichi Nunokawa ◽  
Yasuaki Yamada ◽  
Shuichi Ikeda ◽  
Masao Tomonaga ◽  
...  
Keyword(s):  
T Cell ◽  
Cell Lines ◽  
Leukemia Virus ◽  
Leukemic Cells ◽  
Type I ◽  
T Cell Leukemia ◽  
Cell Leukemia ◽  
Cell Leukemia Virus Type ◽  
Human T Cell ◽  
T Cell Lines

We examined the expression of messenger RNA (mRNA) of the human inducible nitric oxide synthase (hiNOS) gene in a panel of human T-cell lines. Reverse transcriptase-polymerase chain reaction showed that human T-cell leukemia virus type-I (HTLV-I)–infected T-cell lines (MT-1, SLB-1, and C5/MJ) expressed mRNA for the hiNOS, but TL-Om1 or uninfected Jurkat, H9, and CCRF-CEM did not. The MT-1, SLB-1, and C5/MJ cell lines are infected with HTLV-I and express the viral transactivator Tax, whereas TL-Om1 cells, although derived from adult T-cell leukemia (ATL) leukemic cells, do not express Tax. There was, thus, a correlation between Tax and hiNOS mRNA expression. The transcriptional regulatory region of the hiNOS gene was activated by Tax in Jurkat, in which endogenous hiNOS is induced by Tax. Deletion analysis showed that the region of hiNOS encompassing nucleotides −159 to −111 contained the minimum Tax-responsive elements. Mutations in the NF-κB element at position −115 and −106 bp in the hiNOS promoter were still activated by Tax, and a Tax mutant defective for activation of the NF-κB pathway retained the ability to activate the hiNOS promoter. In addition, overexpression of the dominant-negative mutants of IκB and I κBβ failed to reduce Tax-induced activation of hiNOS gene. Furthermore, hiNOS mRNA was detected in leukemic cells from ATL patients. Our results show that the hiNOS promoter contains a minimum Tax-responsive element located between nucleotides −159 and −111, and imply that the expression of the hiNOS gene is involved in the pathogenesis of HTLV-I–associated diseases.

Anti-Adult T-Cell Leukemia Effects of a Novel Synthetic Retinoid, Am80 (Tamibarotene) through Inhibition of NF-κB.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 2525-2525
Author(s):  
Tetsuro Nakazato ◽  
Chie Ishikawa ◽  
Taeko Okudaira ◽  
Mariko Tomita ◽  
Naoki Mori
Keyword(s):  
Cell Cycle ◽  
Retinoic Acid ◽  
T Cell ◽  
Cell Lines ◽  
Type I ◽  
T Cell Leukemia ◽  
Cell Leukemia ◽  
Adult T Cell Leukemia ◽  
Synthetic Retinoid ◽  
T Cell Lines

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.

scholarly journals Apoptosis Induced by the Histone Deacetylase Inhibitor FR901228 in Human T-Cell Leukemia Virus Type 1-Infected T-Cell Lines and Primary Adult T-Cell Leukemia Cells

2004 ◽  
Vol 78 (9) ◽  
pp. 4582-4590 ◽  
Author(s):  
Naoki Mori ◽  
Takehiro Matsuda ◽  
Masayuki Tadano ◽  
Takao Kinjo ◽  
Yasuaki Yamada ◽  
...  
Keyword(s):  
T Cell ◽  
Cell Lines ◽  
Leukemia Virus ◽  
T Cell Leukemia ◽  
Cell Leukemia ◽  
Cell Leukemia Virus Type ◽  
Adult T Cell Leukemia ◽  
Human T Cell ◽  
Induced Apoptosis ◽  
T Cell Lines

ABSTRACT Inhibition of histone deacetylase (HDAC) activity induces growth arrest, differentiation, and, in certain cell types, apoptosis. FR901228, FK228, or depsipeptide, is an HDAC inhibitor effective in T-cell lymphomas. Adult T-cell leukemia (ATL) is caused by human T-cell leukemia virus type 1 (HTLV-1) and remains incurable. We examined whether FR901228 is effective for treatment of ATL by assessing its ability to induce apoptosis of HTLV-1-infected T-cell lines and primary leukemic cells from ATL patients. FR901228 induced apoptosis of Tax-expressing and -unexpressing HTLV-1-infected T-cell lines and selective apoptosis of primary ATL cells, especially those of patients with acute ATL. FR901228 also efficiently reduced the DNA binding of NF-κB and AP-1 in HTLV-1-infected T-cell lines and primary ATL cells and down-regulated the expression of Bcl-xL and cyclin D2, regulated by NF-κB. Although the viral protein Tax is an activator of NF-κB and AP-1, FR901228-induced apoptosis was not associated with reduced expression of Tax. In vivo use of FR901228 partly inhibited the growth of tumors of HTLV-1-infected T cells transplanted subcutaneously in SCID mice. Our results indicated that FR901228 could induce apoptosis of these cells and suppress the expression of NF-κB and AP-1 and suggest that FR901228 could be therapeutically effective in ATL.

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