The T/Tn-Specific Helix pomatia Lectin Induces Cell Death in Lymphoma Cells Negative for T/Tn Antigens

Morniga G is a T/Tn-specific lectin, inducing cell death in Tn-positive leukemias but not in healthy lymphocytes. Helix pomatia lectin (HPA) is another T/Tn-specific lectin, currently used as tool for cancer diagnostics. The HPA-mediated tumor cell death was evaluated on human leukemia and mouse lymphoma cells, and compared to the effect of Morniga G. Both lectins induced an equivalent percentage of cell death in Tn-positive Jurkat human leukemia. In contrast, EL4 mouse lymphoma resisted Morniga G-mediated cytotoxicity but were killed by HPA at concentrations of 2.5 μg/mL (0.032 nM) and higher. In both malignant cells, HPA-mediated cell death showed features compatible with apoptosis (annexin-externalization, caspase-activation, mitochondrial membrane depolarization, and ROS production). Cytometry analysis indicated that EL4 cells are T/Tn-negative. Because previous results showed a high amount of N-acetylgalactosamine (GalNAc, sugar present in Tn antigen) on EL4 cell surface, this GalNAc could be involved in the formation of truncated O-glycans other than the T/Tn residues. When compared to Morniga G, bioinformatic analysis suggested that HPA benefits from an extended carbohydrate-binding site, better adapted than Morniga G to the accommodation of more complex branched and truncated O-glycans (such as core 2). Finally, HPA killed EL4 cells but not healthy lymphocytes in a mixture of lymphoma cells + lymphocytes, suggesting that HPA selectively triggers tumor cell death.

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Insights into the Biological Evaluation of Pterocarpanquinones and Carbapterocarpans with Anti-tumor Activity against MDR Leukemias

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520618666180420165128 ◽

2019 ◽

Vol 19 (1) ◽

pp. 29-37 ◽

Cited By ~ 2

Author(s):

Vivian M. Rumjanek ◽

Raquel C. Maia ◽

Eduardo J. Salustiano ◽

Paulo R.R. Costa

Keyword(s):

Cell Death ◽

Tumor Cell ◽

Cell Lines ◽

Biological Evaluation ◽

Ehrlich Carcinoma ◽

Tumor Cell Lines ◽

Tumor Cell Death ◽

Mitochondrial Membrane Depolarization

In an attempt to find anticancer agents that could overcome multidrug resistance (MDR), two new classes of modified isoflavonoids were designed and synthesized, and their effectiveness evaluated against a vast array of tumor cell lines. Pterocarpanquinone (LQB-118) and 11a-aza-5-carbapterocarpan (LQB-223) were the most promising. LQB-118 induced cell death, in vitro, in the µM range, to a number of human cancer cell lines as well as to fresh tumor cells obtained from patients with acute or chronic myeloid leukemia, independent on whether they exhibit the MDR phenotype or not. Furthermore, leukemic cells were more sensitive to LQB- 118 compared to cells from solid tumors. Given to mice, in vivo, LQB-118 affected the growth of melanoma, Ehrlich carcinoma and prostate cancer cells. Conversely, no general toxicity was observed in vivo, by biochemical, hematological, anatomical or histological parameters and toxicity in vitro against normal cells was low. The process involved in tumor cell death seemed to vary according to cell type. Apoptosis was studied by externalization of phosphatidylserine, DNA fragmentation, caspase-3 activation, reduced expression of XIAP and survivin, ER stress, cytosolic calcium increase and mitochondrial membrane depolarization. Autophagy was also evaluated inhibiting caspase-9, with no effect observed in beclin 1, whereas pre-treatment with rapamycin increased cytotoxicity induced by LQB-118. In addition, LQB-118 increased ROS, inhibited NFκB nuclear translocation and secretion of TNF-α, modulated microRNAs miR-9 and miR-21 and modified the cell cycle. Despite being less studied, the cytotoxic effect of the 11a-aza-5-carbapterocarpan LQB-223 was present against several tumor cell lines, including those with the MDR phenotype.

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Combinatorial Effects of CD30 Ligand Stimulation or Inhibitor of Apoptosis (IAP) Antagonist Exposure with Conventional Chemotherapy on CD30 Positive Malignancies

Blood ◽

10.1182/blood.v116.21.4926.4926 ◽

2010 ◽

Vol 116 (21) ◽

pp. 4926-4926

Author(s):

Kelly J Walkovich ◽

Xuwen Liu ◽

Anne L McCollom ◽

Colin S Duckett

Keyword(s):

Cell Death ◽

Tumor Cell ◽

Cell Lines ◽

Chemotherapeutic Agents ◽

Tumor Cell Lines ◽

Tumor Cell Death ◽

Lymphoma Cells ◽

Cell Death Pathway ◽

Iap Antagonist ◽

Induced Apoptosis

Abstract Abstract 4926 CD30 is a member of the tumor necrosis factor (TNF) receptor family that is normally found on the cell surface of a small subset of activated lymphocytes but is overexpressed on the surface of anaplastic large cell lymphoma (ALCL) and Hodgkins lymphoma (HL) cells. Although many drugs exist that treat lymphomas by triggering the intrinsic cell death pathway, current chemotherapeutic regimens are limited by unwanted side effects, including secondary malignancies that limit event-free survival. The tumor-restricted overexpression of CD30 makes it an attractive target for therapeutic intervention. Depending on the cellular context, CD30 stimulation has been linked to cell death, cell cycle arrest, or paradoxically, proliferation. In ALCL tumor cell lines, CD30 stimulation activates both the canonical and noncanonical NF-kB pathways while in HL tumor cell lines, CD30 stimulation only slightly enhances NF-kB activity above constitutive levels, implying a role for NF-kB in determining the sensitivity or resistance of lymphoma cells to CD30-induced apoptosis. In addition, IAP antagonists, small synthetic compounds that mimic the structure of the second mitochondrial activator of caspase (Smac) and target IAP molecules that affect the activation of the non-canonical NF-kB pathway, induce apoptosis and/or sensitize cells to death via secondary signals such as TNF. This suggests that the modulation of IAP levels, and consequently regulation of the non-canonical NF-kB pathways, may also have a role in determining tumor cell death. Using representative ALCL and HL tumor cell lines, we have found that CD30 stimulation via its physiologically ligand in combination with standard chemotherapeutic agents results in increased efficacy in tumor cell death in the majority of ALCL cell lines but not HL cell lines. Similarly, IAP antagonists in combination with standard chemotherapeutic agents also resulted in enhanced tumor cell death in most ALCL but not HL cell lines. This augmentation of tumor cell death suggests that CD30-induced apoptosis and IAP antagonist-induced killing may have important consequences in the clinical treatment of CD30 positive malignancies. Currently, we are further investigating the role of both CD30 stimulation via its physiological ligand and IAP antagonists in impacting the activation of the canonical and noncanonical NF-kB pathways alone and in combination with currently utilized chemotherapeutic agents to modulate the apoptotic threshold in CD30 positive lymphoma cells. Disclosures: No relevant conflicts of interest to declare.

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Accelerated Tumor Cell Death by Anglogenic Modifiers

10.21236/ada441865 ◽

2005 ◽

Author(s):

Leland W. K. Chung

Keyword(s):

Cell Death ◽

Tumor Cell ◽

Tumor Cell Death

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Combined Inhibition of Chk1 and MEK1/2 Leads to Tumor Cell Death In Vivo

10.21236/ada446698 ◽

2005 ◽

Author(s):

Paul Dent

Keyword(s):

Cell Death ◽

Tumor Cell ◽

Tumor Cell Death

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Cellular cytotoxicity is a form of immunogenic cell death

Journal for ImmunoTherapy of Cancer ◽

10.1136/jitc-2019-000325 ◽

2020 ◽

Vol 8 (1) ◽

pp. e000325 ◽

Cited By ~ 3

Author(s):

Luna Minute ◽

Alvaro Teijeira ◽

Alfonso R Sanchez-Paulete ◽

Maria C Ochoa ◽

Maite Alvarez ◽

...

Keyword(s):

T Cells ◽

Cell Death ◽

Dendritic Cells ◽

Tumor Cell ◽

Tumor Cells ◽

Cd8 T Cells ◽

Immunogenic Cell Death ◽

Cell Debris ◽

Tumor Cell Death ◽

Mhc Multimer

BackgroundThe immune response to cancer is often conceptualized with the cancer immunity cycle. An essential step in this interpretation is that antigens released by dying tumors are presented by dendritic cells to naive or memory T cells in the tumor-draining lymph nodes. Whether tumor cell death resulting from cytotoxicity, as mediated by T cells or natural killer (NK) lymphocytes, is actually immunogenic currently remains unknown.MethodsIn this study, tumor cells were killed by antigen-specific T-cell receptor (TCR) transgenic CD8 T cells or activated NK cells. Immunogenic cell death was studied analyzing the membrane exposure of calreticulin and the release of high mobility group box 1 (HMGB1) by the dying tumor cells. Furthermore, the potential immunogenicity of the tumor cell debris was evaluated in immunocompetent mice challenged with an unrelated tumor sharing only one tumor-associated antigen and by class I major histocompatibility complex (MHC)-multimer stainings. Mice deficient inBatf3,Ifnar1andSting1were used to study mechanistic requirements.ResultsWe observe in cocultures of tumor cells and effector cytotoxic cells, the presence of markers of immunogenic cell death such as calreticulin exposure and soluble HMGB1 protein. Ovalbumin (OVA)-transfected MC38 colon cancer cells, exogenously pulsed to present the gp100 epitope are killed in culture by mouse gp100-specific TCR transgenic CD8 T cells. Immunization of mice with the resulting destroyed cells induces epitope spreading as observed by detection of OVA-specific T cells by MHC multimer staining and rejection of OVA+EG7 lymphoma cells. Similar results were observed in mice immunized with cell debris generated by NK-cell mediated cytotoxicity. Mice deficient inBatf3-dependent dendritic cells (conventional dendritic cells type 1, cDC1) fail to develop an anti-OVA response when immunized with tumor cells killed by cytotoxic lymphocytes. In line with this, cultured cDC1 dendritic cells uptake and can readily cross-present antigen from cytotoxicity-killed tumor cells to cognate CD8+T lymphocytes.ConclusionThese results support that an ongoing cytotoxic antitumor immune response can lead to immunogenic tumor cell death.

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