Anticancer Drugs Up-regulate HspBP1 and Thereby Antagonize the Prosurvival Function of Hsp70 in Tumor Cells

The 70-kDa heat shock protein (Hsp70) is up-regulated in a wide variety of tumor cell types and contributes to the resistance of these cells to the induction of cell death by anticancer drugs. Hsp70 binding protein 1 (HspBP1) modulates the activity of Hsp70 but its biological significance has remained unclear. We have now examined whether HspBP1 might interfere with the prosurvival function of Hsp70, which is mediated, at least in part, by inhibition of the death-associated permeabilization of lysosomal membranes. HspBP1 was found to be expressed at a higher level than Hsp70 in all normal and tumor cell types examined. Tumor cells with a high HspBP1/Hsp70 molar ratio were more susceptible to anticancer drugs than were those with a low ratio. Ectopic expression of HspBP1 enhanced this effect of anticancer drugs in a manner that was both dependent on the ability of HspBP1 to bind to Hsp70 and sensitive to the induction of Hsp70 by mild heat shock. Furthermore, anticancer drugs up-regulated HspBP1 expression, whereas prevention of such up-regulation by RNA interference reduced the susceptibility of tumor cells to anticancer drugs. Overexpression of HspBP1 promoted the permeabilization of lysosomal membranes, the release of cathepsins from lysosomes into the cytosol, and the activation of caspase-3 induced by anticancer drugs. These results suggest that HspBP1, by antagonizing the prosurvival activity of Hsp70, sensitizes tumor cells to cathepsin-mediated cell death.

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Bortezomib enhances dendritic cell (DC)–mediated induction of immunity to human myeloma via exposure of cell surface heat shock protein 90 on dying tumor cells: therapeutic implications

Blood ◽

10.1182/blood-2006-10-054221 ◽

2007 ◽

Vol 109 (11) ◽

pp. 4839-4845 ◽

Cited By ~ 250

Author(s):

Radek Spisek ◽

Anna Charalambous ◽

Amitabha Mazumder ◽

David H. Vesole ◽

Sundar Jagannath ◽

...

Keyword(s):

Cell Death ◽

Heat Shock ◽

Heat Shock Protein ◽

Tumor Cell ◽

Tumor Cells ◽

Antitumor Immunity ◽

Heat Shock Protein 90 ◽

Human Tumors ◽

Tumor Cell Death ◽

Dying Cells

Abstract Most anticancer chemotherapies are immunosuppressive and induce nonimmunogenic tumor cell death. Bortezomib, a specific inhibitor of 26S proteasome, has shown clinical activity in several human tumors, including myeloma. Here we show that the uptake of human myeloma cells by dendritic cells (DCs) after tumor cell death by bortezomib, but not γ irradiation or steroids, leads to the induction of antitumor immunity, including against primary tumor cells, without the need for any additional adjuvants. The delivery of activating signal from bortezomib-killed tumor cells to DCs depends on cell-cell contact between DCs and dying tumor cells and is mediated by bortezomib-induced exposure of heat shock protein 90 (hsp90) on the surface of dying cells. The combination of bortezomib and geldanamycin (an hsp90 inhibitor) leads to greater apoptosis of tumor cells but abrogates their immunogenicity. These data identify drug-induced exposure of endogenous heat shock proteins on the surface of dying cells as a mechanism of immunogenic death of human tumors. Specific targeting of bortezomib to tumors may enhance their immunogenicity and the induction of antitumor immunity.

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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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Induction of Apoptosis of Metastatic Mammary Carcinoma Cells In Vivo by Disruption of Tumor Cell Surface CD44 Function

Journal of Experimental Medicine ◽

10.1084/jem.186.12.1985 ◽

1997 ◽

Vol 186 (12) ◽

pp. 1985-1996 ◽

Cited By ~ 172

Author(s):

Qin Yu ◽

Bryan P. Toole ◽

Ivan Stamenkovic

Keyword(s):

Cell Surface ◽

Tumor Cell ◽

Tumor Cells ◽

Lung Tissue ◽

Mammary Carcinoma ◽

Cell Types ◽

Pulmonary Endothelium ◽

Soluble Cd44

To understand how the hyaluronan receptor CD44 regulates tumor metastasis, the murine mammary carcinoma TA3/St, which constitutively expresses cell surface CD44, was transfected with cDNAs encoding soluble isoforms of CD44 and the transfectants (TA3sCD44) were compared with parental cells (transfected with expression vector only) for growth in vivo and in vitro. Local release of soluble CD44 by the transfectants inhibited the ability of endogenous cell surface CD44 to bind and internalize hyaluronan and to mediate TA3 cell invasion of hyaluronan-producing cell monolayers. Mice intravenously injected with parental TA3/St cells developed massive pulmonary metastases within 21–28 d, whereas animals injected with TA3sCD44 cells developed few or no tumors. Tracing of labeled parental and transfectant tumor cells revealed that both cell types initially adhered to pulmonary endothelium and penetrated the interstitial stroma. However, although parental cells were dividing and forming clusters within lung tissue 48 h following injection, >80% of TA3sCD44 cells underwent apoptosis. Although sCD44 transfectants displayed a marked reduction in their ability to internalize and degrade hyaluronan, they elicited abundant local hyaluronan production within invaded lung tissue, comparable to that induced by parental cells. These observations provide direct evidence that cell surface CD44 function promotes tumor cell survival in invaded tissue and that its suppression can induce apoptosis of the invading tumor cells, possibly as a result of impairing their ability to penetrate the host tissue hyaluronan barrier.

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Lymphoid Tumors ofXenopus laeviswith Different Capacities for Growth in Larvae and Adults

Developmental Immunology ◽

10.1155/1994/37392 ◽

1994 ◽

Vol 3 (4) ◽

pp. 297-307 ◽

Cited By ~ 50

Author(s):

Jacques Robert ◽

Chantal Guiet ◽

Louis Du Pasquier

Keyword(s):

Cell Surface ◽

Tumor Cell ◽

Tumor Cells ◽

Mhc Class I ◽

Mhc Class Ii ◽

Cell Lineage ◽

Cell Types ◽

Class Ii ◽

Class I ◽

Specific Marker

Three new lymphoid tumors offering an assortment of variants in terms of MHC class I expressions, MHC class II expression, and Ig gene transcription have been discovered in the amphibianXenopus. One was developed in an individual of the isogenic LG15 clone (LG15/0), one in a frog of the LG15/40 clone (derived from a small egg recombinant of LG15), and one (ff-2) in a maleffsib of the individual in which MAR1, the first lymphoid tumor in Xenopus was found 2 years ago. These tumors developed primarily as thymus outgrowths and were transplantable in histocompatible tadpoles but not in nonhistocompatible hosts. Whereas LG15/0 and LG15/40 tumor cells also grow in adult LG15 frogs, theff-2 tumor, like the MAR1 cell line, is rejected by adultffanimals. Using flow cytometry with fluorescence-labeled antibodies and immunoprecipitation analysis, we could demonstrate that, like MAR1, these three new tumors express on their cell surface lymphopoietic markers recognized by mAbs FIF6 and RC47, as well as T-cell lineage markers recognized by mAbs AM22 (CD8-1ike) and X21.2, but not by immunologobulin (Ig) nor MHC class II molecules. Another lymphocyte-specific marker AM15 is expressed by 15/0 and 15/40 but notff-2 tumor cells. Theff-2 tumor cell expresses MHC class molecule in association withβ2-microglobulin on the surface, 15/40 cells contain cytoplasmic Iαchain that is barely detected at the cell surface by fluocytometry, and 15/0 cells do not synthesize class Iαchain at all. The three new tumors all produce large amounts of IgM mRNA of two different sizes but no Ig protein on the membrane nor in the cytoplasm. All tumor cell types synthesize large amount of Myc mRNA and MHC class I-like transcripts considered to be non classical.

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Apoptosis and Tumor Cell Death in Response to HAMLET (Human α-Lactalbumin Made Lethal to Tumor Cells)

Advances in Experimental Medicine and Biology - Bioactive Components of Milk ◽

10.1007/978-0-387-74087-4_8 ◽

2007 ◽

pp. 217-240 ◽

Cited By ~ 40

Author(s):

Oskar Hallgren ◽

Sonja Aits ◽

Patrick Brest ◽

Lotta Gustafsson ◽

Ann-Kristin Mossberg ◽

...

Keyword(s):

Cell Death ◽

Tumor Cell ◽

Tumor Cells ◽

Tumor Cell Death

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Membrane-bound TNF mediates microtubule-targeting chemotherapeutics-induced cancer cytolysis via juxtacrine inter-cancer-cell death signaling

Cell Death and Differentiation ◽

10.1038/s41418-019-0441-3 ◽

2019 ◽

Vol 27 (5) ◽

pp. 1569-1587 ◽

Cited By ~ 2

Author(s):

Jing Zhang ◽

Yu Yang ◽

Shen’ao Zhou ◽

Xueyan He ◽

Xuan Cao ◽

...

Keyword(s):

Cell Death ◽

Tumor Cells ◽

Cancer Cell ◽

Tumor Regression ◽

Cell Types ◽

Tight Contact ◽

Cancer Cell Death ◽

Microtubule Targeting Agents ◽

Patient Responsiveness ◽

Smac Mimetics

Abstract Microtubule-targeting agents (MTAs) are a class of most widely used chemotherapeutics and their mechanism of action has long been assumed to be mitotic arrest of rapidly dividing tumor cells. In contrast to such notion, here we show—in many cancer cell types—MTAs function by triggering membrane TNF (memTNF)-mediated cancer-cell-to-cancer-cell killing, which differs greatly from other non-MTA cell-cycle-arresting agents. The killing is through programmed cell death (PCD), either in way of necroptosis when RIP3 kinase is expressed, or of apoptosis in its absence. Mechanistically, MTAs induce memTNF transcription via the JNK-cJun signaling pathway. With respect to chemotherapy regimens, our results establish that memTNF-mediated killing is significantly augmented by IAP antagonists (Smac mimetics) in a broad spectrum of cancer types, and with their effects most prominently manifested in patient-derived xenograft (PDX) models in which cell–cell contacts are highly reminiscent of human tumors. Therefore, our finding indicates that memTNF can serve as a marker for patient responsiveness, and Smac mimetics will be effective adjuvants for MTA chemotherapeutics. The present study reframes our fundamental biochemical understanding of how MTAs take advantage of the natural tight contact of tumor cells and utilize memTNF-mediated death signaling to induce the entire tumor regression.

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Tumor quiescence: elevating SOX2 in diverse tumor cell types downregulates a broad spectrum of the cell cycle machinery and inhibits tumor growth

BMC Cancer ◽

10.1186/s12885-020-07370-7 ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Ethan P. Metz ◽

Erin L. Wuebben ◽

Phillip J. Wilder ◽

Jesse L. Cox ◽

Kaustubh Datta ◽

...

Keyword(s):

Cell Cycle ◽

Cell Proliferation ◽

Tumor Growth ◽

Tumor Cell ◽

Tumor Cells ◽

Molecular Mechanisms ◽

Cell Types ◽

Cell Cycle Machinery

Abstract Background Quiescent tumor cells pose a major clinical challenge due to their ability to resist conventional chemotherapies and to drive tumor recurrence. Understanding the molecular mechanisms that promote quiescence of tumor cells could help identify therapies to eliminate these cells. Significantly, recent studies have determined that the function of SOX2 in cancer cells is highly dose dependent. Specifically, SOX2 levels in tumor cells are optimized to promote tumor growth: knocking down or elevating SOX2 inhibits proliferation. Furthermore, recent studies have shown that quiescent tumor cells express higher levels of SOX2 compared to adjacent proliferating cells. Currently, the mechanisms through which elevated levels of SOX2 restrict tumor cell proliferation have not been characterized. Methods To understand how elevated levels of SOX2 restrict the proliferation of tumor cells, we engineered diverse types of tumor cells for inducible overexpression of SOX2. Using these cells, we examined the effects of elevating SOX2 on their proliferation, both in vitro and in vivo. In addition, we examined how elevating SOX2 influences their expression of cyclins, cyclin-dependent kinases (CDKs), and p27Kip1. Results Elevating SOX2 in diverse tumor cell types led to growth inhibition in vitro. Significantly, elevating SOX2 in vivo in pancreatic ductal adenocarcinoma, medulloblastoma, and prostate cancer cells induced a reversible state of tumor growth arrest. In all three tumor types, elevation of SOX2 in vivo quickly halted tumor growth. Remarkably, tumor growth resumed rapidly when SOX2 returned to endogenous levels. We also determined that elevation of SOX2 in six tumor cell lines decreased the levels of cyclins and CDKs that control each phase of the cell cycle, while upregulating p27Kip1. Conclusions Our findings indicate that elevating SOX2 above endogenous levels in a diverse set of tumor cell types leads to growth inhibition both in vitro and in vivo. Moreover, our findings indicate that SOX2 can function as a master regulator by controlling the expression of a broad spectrum of cell cycle machinery. Importantly, our SOX2-inducible tumor studies provide a novel model system for investigating the molecular mechanisms by which elevated levels of SOX2 restrict cell proliferation and tumor growth.

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Hypoxia-activated ligand HAL-1/13 is lupus autoantigen Ku80 and mediates lymphoid cell adhesion in vitro

AJP Cell Physiology ◽

10.1152/ajpcell.2001.280.4.c897 ◽

2001 ◽

Vol 280 (4) ◽

pp. C897-C911 ◽

Cited By ~ 25

Author(s):

Eileen M. Lynch ◽

Robert B. Moreland ◽

Irene Ginis ◽

Susan P. Perrine ◽

Douglas V. Faller

Keyword(s):

Tumor Cell ◽

Tumor Cells ◽

Cell Lines ◽

Lymphoid Cell ◽

Ectopic Expression ◽

Lymphoid Cells ◽

Expression Cloning ◽

Hypoxic Exposure ◽

Tumor Cell Lines ◽

Human Lymphoid Cell

Hypoxia is known to induce extravasation of lymphocytes and leukocytes during ischemic injury and increase the metastatic potential of malignant lymphoid cells. We have recently identified a new adhesion molecule, hypoxia-activated ligand-1/13 (HAL-1/13), that mediates the hypoxia-induced increases in lymphocyte and neutrophil adhesion to endothelium and hypoxia-mediated invasion of endothelial cell monolayers by tumor cells. In this report, we used expression cloning to identify this molecule as the lupus antigen and DNA-dependent protein kinase-associated nuclear protein, Ku80. The HAL-1/13-Ku80 antigen is present on the surface of leukemic and solid tumor cell lines, including T and B lymphomas, myeloid leukemias, neuroblastoma, rhabdomyosarcoma, and breast carcinoma cells. Transfection and ectopic expression of HAL-1/13-Ku80 on (murine) NIH/3T3 fibroblasts confers the ability of these normally nonadhesive cells to bind to a variety of human lymphoid cell lines. This adhesion can be specifically blocked by HAL-1/13 or Ku80-neutralizing antibodies. Loss of expression variants of these transfectants simultaneously lost their adhesive properties toward human lymphoid cells. Hypoxic exposure of tumor cell lines resulted in upregulation of HAL-1/13-Ku80 expression at the cell surface, mediated by redistribution of the antigen from the nucleus. These studies indicate that the HAL-1/13-Ku80 molecule may mediate, in part, the hypoxia-induced adhesion of lymphocytes, leukocytes, and tumor cells.

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Cross-Resistance of CD95- and Drug-Induced Apoptosis as a Consequence of Deficient Activation of Caspases (ICE/Ced-3 Proteases)

Blood ◽

10.1182/blood.v90.8.3118 ◽

1997 ◽

Vol 90 (8) ◽

pp. 3118-3129 ◽

Cited By ~ 123

Author(s):

Marek Los ◽

Ingrid Herr ◽

Claudia Friesen ◽

Simone Fulda ◽

Klaus Schulze-Osthoff ◽

...

Keyword(s):

Cell Death ◽

Drug Treatment ◽

Tumor Cells ◽

Anticancer Drugs ◽

Ex Vivo ◽

Resistant Cell ◽

Cross Resistance ◽

Strong Increase ◽

Drug Induced ◽

Induced Apoptosis

Abstract The cytotoxic effect of anticancer drugs has been shown to involve induction of apoptosis. We report here that tumor cells resistant to CD95 (APO-1/Fas) -mediated apoptosis were cross-resistant to apoptosis-induced by anticancer drugs. Apoptosis induced in tumor cells by cytarabine, doxorubicin, and methotrexate required the activation of ICE/Ced-3 proteases (caspases), similarly to the CD95 system. After drug treatment, a strong increase of caspase activity was found that preceded cell death. Drug-induced activation of caspases was also found in ex vivo-derived T-cell leukemia cells. Resistance to cell death was conferred by a peptide caspase inhibitor and CrmA, a poxvirus-derived serpin. The peptide inhibitor was effective even if added several hours after drug treatment, indicating a direct involvement of caspases in the execution and not in the trigger phase of drug action. Drug-induced apoptosis was also strongly inhibited by antisense approaches targeting caspase-1 and -3, indicating that several members of this protease family were involved. CD95-resistant cell lines that failed to activate caspases upon CD95 triggering were cross-resistant to drug-mediated apoptosis. Our data strongly support the concept that sensitivity for drug-induced cell death depends on intact apoptosis pathways leading to activation of caspases. The identification of defects in caspase activation may provide molecular targets to overcome drug resistance in tumor cells.

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Smart multifunctional polyurethane microcapsules for the quick release of anticancer drugs in BGC 823 and HeLa tumor cells

Journal of Materials Chemistry B ◽

10.1039/c7tb02570j ◽

2017 ◽

Vol 5 (48) ◽

pp. 9477-9481 ◽

Cited By ~ 33

Author(s):

Yuqing Niu ◽

Florian J. Stadler ◽

Tao He ◽

Xingcai Zhang ◽

Yingjie Yu ◽

...

Keyword(s):

Cancer Therapy ◽

Tumor Cell ◽

Real Time ◽

Tumor Cells ◽

Anticancer Drugs ◽

Real Time Monitoring ◽

Triggered Release ◽

Quick Release ◽

Cell Internalization

Smart fluorescent polyurethane microcapsules with high tumor cell internalization, triggered release were developed for precision real-time monitoring cancer therapy.

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