Screening of Promising Chemotherapeutic Candidates from Plants against Human Adult T-Cell Leukemia/Lymphoma (VII): Active Principles from Thuja occidentalis L

During the screening of novel chemotherapeutic candidates from plants against adult T-cell leukemia/lymphoma, we identified that the extracts of Thuja occidentalis (Cupressaceae) showed potent anti-proliferative activity in MT-1 and MT-2 cells. Therefore, we attempted to isolate the active components from this plant. We isolated and identified 32 compounds (1–32; eight lignans, 18 terpenoids, and six flavonoids) from the extracts of the leaves and cones. Their structures were determined by spectroscopic analysis. Several of the isolated compounds inhibited the growth of both cell lines. Lignans showed more potent activity than other classes of compounds. A comparison of the activities of compounds 1–8 revealed that the presence of a trans-lactone (linkage of C-6 to C-7) correlated with increased activity. Diterpenes showed moderate activity, and the presence of a ketone moiety at the C-7 position correlated with increased activity in compounds 12–21. In addition, biflavones showed moderate activity, and the presence of methoxy functions appeared to influence the activity of these compounds. Several lignans were lead compound of anti-cancer reagent (etoposide). In conclusion, not only lignans, but also diterpenes and/or biflavones, may be promising candidates for the treatment of adult T-cell leukemia/lymphoma.

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Testing the Addition of an Anti-cancer Drug, Lenalidomide, to the Usual Combination Chemotherapy Treatment ("EPOCH") for Adult T-Cell Leukemia-Lymphoma (ATL)

Case Medical Research ◽

10.31525/ct1-nct04301076 ◽

2020 ◽

Author(s):

Keyword(s):

T Cell ◽

Combination Chemotherapy ◽

Cancer Drug ◽

T Cell Leukemia ◽

Cell Leukemia ◽

Chemotherapy Treatment ◽

Adult T Cell Leukemia ◽

Anti Cancer

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The Osteoclast Targeting Therapy In Bone Metastasis For a Mouse Model Of Adult T Cell Leukemia

Blood ◽

10.1182/blood.v122.21.3691.3691 ◽

2013 ◽

Vol 122 (21) ◽

pp. 3691-3691

Author(s):

Takuo Mizukami ◽

Kazuya Takizawa ◽

Jumpei Yamazaki ◽

Wakako Kuribayashi ◽

Madoka Kuramitsu ◽

...

Keyword(s):

T Cell ◽

Mouse Model ◽

Trabecular Bone ◽

Scid Mouse ◽

Cancer Drug ◽

T Cell Leukemia ◽

Cell Leukemia ◽

Lymphoma Cells ◽

Adult T Cell Leukemia ◽

Anti Cancer

Abstract Adult T cell leukemia (ATL) is a lymphoproliferative disorder caused by infection with HTLV-I. Although various chemotherapies have shown significant complete remission rates, most of the treated patients relapse. These data indicate the existence of leukemic stem cells (LSCs) and a specific niche that regulates stemness and protects LSCs from various chemotherapies. We have reported in previous studies that the ATL-LSCs isolated from a Tax-transgenic (Tax-Tg) mouse are enriched in the CD117+/CD38–/CD71– fraction of the lymphoma, and LSCs have the potential to reproduce the original tumor when transplanted into a NOD/SCID mouse (Yamazaki et al., Blood, 2009). However, the niche of ATL-LSCs is still unclear. To identify the ATL-LSC niche in vivo, we performed a homing assay. Splenic lymphoma cells isolated from a Tax-Tg mouse were GFP transduced by a lentivirus, and then sorted GFP+ cells were transplanted intra-peritoneally into a non-irradiated NOD/SCID mouse. The homing of GFP+ cells to tissues was assessed by flow cytometry (FCM) at 16 hours and 3, 7, 14 and 21 days after transplantation. As a result, GFP+ lymphoma cells were first detected in the spleen and BM at 16 hours after transplantation. No GFP+ lymphoma cells were detected in the thymus and LN. Interestingly, more than 60% of first colonized cells in the spleen and BM at 16 hours after transplantation were AT-LSCs (GFP+/CD117+ cells). From day 3 to 7, more than 40% of colonizing cells in the BM and spleen were ATL-LSCs. To identify the specific niche of ATL-LSCs in the BM, we performed imaging analysis of ATL-LSCs. ATL-LSCs (GFP+/CD117+ and CD38–/CD71–/CD117+ cells) were mainly localized near the endosteal region of trabecular bone in the BM. We found that ATL-LSCs were also attached to the reticular cells in the trabecular bone. In addition, we found the number of osteoclast was significantly increased at the trabecular region. Increasing number of osteoclasts correlates the increased the serum calcium concentration and decreased the mass of trabecular bone. FCM analysis and in vitro differentiation assay confirmed that the number of osteoclast precursors was increased in the ATL BM. To clarify the role of osteoclast in the ATL BM, we treated osteoclast inhibitor Zoledronic acid (ZOL) to the ATL mouse model. As a result, ZOL itself significantly reduced the number of GFP+ ATL cells in the BM. When we treated ZOL with anti cancer drug, GFP+ ATL cells were dramatically reduced in the BM and extend the mouse survival rate significantly despite anti cancer drug does not reduced the number of ATL cells itself. In addition, abnormal trabecular bone morphology was completely recovered in the treated mouse. These data suggest that osteoclast may have a function to support leukemic stem cell niche. To clarify the key signals to induce osteoclast in ATL BM, we checked the expression of RANKL and PTHrP. We found that RANKL was up-regulated both in the lymphoma cell and stromal cells in the bone marrow. 　　In this study, we found that ATL-LSC niche is located at the trabecular bone region in the BM and osteoclasts have a role to support ATL cell and develop LSCs niche in a mouse model of ATL. We conclude that osteoclast have a potential therapeutic target in the mouse model of ATL. Disclosures: No relevant conflicts of interest to declare.

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Dihydroflavonol BB-1, an Extract of Natural Plant Blumea Balsamifera, Abrogates TRAIL Resistance in Adult T-Cell Leukemia/Lymphoma.

Blood ◽

10.1182/blood.v104.11.2290.2290 ◽

2004 ◽

Vol 104 (11) ◽

pp. 2290-2290

Author(s):

Hiroo Hasegawa ◽

Yasuaki Yamada ◽

Masahiko Hayashi ◽

Masami Ishibashi ◽

Kanki Komiyama ◽

...

Keyword(s):

T Cell ◽

Annexin V ◽

Caspase 8 ◽

T Cell Leukemia ◽

Cell Leukemia ◽

Adult T Cell Leukemia ◽

Anti Cancer ◽

Trail Resistance ◽

Apoptotic Proteins ◽

Trail Sensitivity

Abstract TNF-related apoptosis-inducing ligand (TRAIL) induces apoptosis in many transformed cells but not in normal cells, hence TRAIL has recently emerged as a novel anti-cancer agent. Adult T-cell Leukemia/Lymphoma (ATLL) is a neoplasm of T-lymphocyte origin etiologically associated with HTLV-I, and is known to be resistant to standard anti-cancer therapies. In a previous study, we showed that although most ATLL cells express TRAIL-death receptors DR4 and/or DR5, they are resistant to TRAIL. To overcome this resistance, we tried to find natural materials that increase the sensitivity to TRAIL in the present study. Here, we report for the first time that dihydroflavonol from a plant increases TRAIL sensitivity by enhancing death receptor expression. Materials and methods: We used a TRAIL-resistant ATLL cell line, KOB, for screening, and peripheral blood mononuclear cells (PBMCs) from normal healthy donors. The cell surface expression of DR4, DR5, and decoy-receptors DcR1 and DcR2 was examined using flow cytometry (FCM). Cell viability was assessed by MTS assay after incubation with various combinations of natural extracts and TRAIL for 48 hours. Apoptosis was evaluated by Annexin V binding and propidium iodide (PI) staining. We also analyzed caspase−8, − 9 and −3 activation and pro- and anti-apoptotic proteins by Western blot. Results and Discussion: We screened more than 500 natural products. Among them, the most striking synergism with TRAIL was observed in a dihydroflavonol that was extracted from the Blumea Balsamifera, a family of chrysanthemum from Thailand. It was a methyldihydroquercetin (molecular weight, 318), and we named it BB-1. The viability of KOB cells treated with either TRAIL or BB-1 was 98% and 97%, respectively, and decreased to 60% with concurrent treatment. Interestingly, sequential treatment, pre-treatment with BB-1 followed by TRAIL, further augmented the synergism, and the viability decreased to 38%. Using Annexin V and PI, we confirmed that these are the results of apoptosis. Although it has been reported that anti-apoptotic proteins FLIP, Bcl-2, Bcl-xL and XIAP play key roles in TRAIL resistance, we did not find any change in these factors in the BB-1-treated cells. Instead, we found that BB-1 increased DR5 expression. Subsequent activation of caspase−8, −9 and −3 was observed in a time-dependent manner in the sequentially treated cells, but not in cells treated with BB-1 or TRAIL alone. More importantly, BB1 did not induce DR5 expression or enhance TRAIL sensitivity in PBMCs. Thus, BB-1 augmented TRAIL-induced apoptosis by up-regulating DR5 expression without any cytotoxic activity on normal PBMCs. These results suggest that combined treatment with BB-1 and TRAIL can be a new strategy for cancer immunotherapy against TRAIL-resistant cells.

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