Enhanced expression of proapoptotic and autophagic proteins involved in the cell death of glioblastoma induced by synthetic glycans

2014 ◽  
Vol 120 (6) ◽  
pp. 1298-1308 ◽  
Author(s):  
Ahmad Faried ◽  
Muhammad Zafrullah Arifin ◽  
Shogo Ishiuchi ◽  
Hiroyuki Kuwano ◽  
Shin Yazawa

Object Glioblastoma is the most aggressive malignant brain tumor, and overall patient survival has not been prolonged even by conventional therapies. Previously, the authors found that chemically synthesized glycans could be anticancer agents against growth of a series of cancer cells. In this study, the authors examined the effects of glycans on the growth of glioblastoma cells both in vitro and in vivo. Methods The authors investigated not only the occurrence of changes in the cell signaling molecules and expression levels of various proteins related to cell death, but also a mouse model involving the injection of glioblastoma cells following the administration of synthetic glycans. Results Synthetic glycans inhibited the growth of glioblastoma cells, induced the apoptosis of the cells with cleaved poly (adenosine diphosphate-ribose) polymerase (PARP) expression and DNA fragmentation, and also caused autophagy, as shown by the detection of autophagosome proteins and monodansylcadaverine staining. Furthermore, tumor growth in the in vivo mouse model was significantly inhibited. A dramatic induction of programmed cell death was found in glioblastoma cells after treatment with synthetic glycans. Conclusions These results suggest that synthetic glycans could be a promising novel anticancer agent for performing chemotherapy against glioblastoma.

2019 ◽  
Vol 39 (12) ◽  
Author(s):  
Jingjing Liu ◽  
Hongsheng Liang ◽  
Chen Chen ◽  
Xiaoxing Wang ◽  
Faling Qu ◽  
...  

Abstract Glioma is one of the most common types of primary brain tumors. Ivermectin (IVM), a broad-spectrum antiparasitic drug, has been identified as a novel anticancer agent due to its inhibitory effects on the proliferation of glioma cells in vitro and in vivo. However, the ability of IVM to induce autophagy and its role in glioma cell death remains unclear. The main objective of the present study was to explore autophagy induced by IVM in glioma U251 and C6 cells, and the deep underlying molecular mechanisms. In addition, we examined the effects of autophagy on apoptosis in glioma cells. In the present study, transmission electron microscopy (TEM), immunofluorescence, Western blot and immunohistochemistry were used to evaluate autophagy activated by IVM. Cell viability was measured by 3-(4,5-dimethylthiazol2-yl)-2, 5-diphenyltetrazolium bromide (MTT) and colony formation assay. The apoptosis rate was detected by flow cytometry and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL). Meanwhile, autophagy inhibition was achieved by using chloroquine (CQ). U251-derived xenografts were established for examination of IVM-induced autophagy on glioma in vivo. Taken together, the results of the present study showed that autophagy induced by IVM has a protective effect on cell apoptosis in vitro and in vivo. Mechanistically, IVM induced autophagy through AKT/mTOR signaling and induced energy impairment. Our findings show that IVM is a promising anticancer agent and may be a potential effective treatment for glioma cancers.


Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 1510-1510 ◽  
Author(s):  
Joseph D. Growney ◽  
Peter Atadja ◽  
Wenlin Shao ◽  
Youzhen Wang ◽  
Minying Pu ◽  
...  

Abstract Panobinostat (LBH589) is a highly potent oral pan-deacetylase (DAC) inhibitor currently undergoing clinical development in hematologic and solid malignancies. Here we report the effects of panobinostat on multiple myeloma (MM) cells in vitro and in a murine xenograft model in vivo. Panobinostat exhibited potent cytotoxic activity (IC50 <10 nM) against 8 MM cell lines (KMS-12PE, KMS-18, LP-1, NCI H929, KMS-11, RPMI8226, OPM-2, and U266). Panobinostat has been shown to affect signals involved in MM cell-cycle arrest and cell death, and to induce apoptosis via mitochondrial perturbation. In addition, panobinostat has been shown to selectively induce cell death of plasma cells isolated from MM patients without toxicity to normal lymphocytes or granulocytes. To investigate the effect of panobinostat in vivo, a disseminated luciferized MM.1S xenograft mouse model was treated with vehicle or panobinostat 15 mg/kg by intraperitoneal (i.p.) administration qd×5 for 3 weeks. Panobinostat treatment reduced the burden of MM.1S tumor cells to 22% treated over control (T/C) relative to vehicle-treated animals. In addition, MM.1S tumor-bearing mice treated with panobinostat displayed reduced trabecular and cortical bone damage relative to vehicle-treated animals. The mean ± SEM trabecular bone density and cortical bone density (% Bone Volume/Total Volume) of panobinostat-treated animals was 14.5% ± 2.0 and 98.1% ± 0.4, respectively, compared with 2.2% ± 0.3 and 89.1% ± 1.5 in vehicle-treated animals. In combination with the proteosome inhibitor bortezomib (BZ), panobinostat displayed significant synergistic cytotoxicity without additional toxicity to normal bone marrow stromal cells in vitro. In the MM.1S-luciferase tumor mouse model, combined treatment with panobinostat at 10 mg/kg i.p. qd×5 for 4 weeks and BZ at 0.2 mg/kg intravenously 1qw for 4 weeks reduced tumor burden to 7% T/C relative to vehicle, panobinostat alone (31% T/C), or BZ alone (44% T/C). Disease progression, measured as median time to endpoint (TTE) was improved from 37 to 54 days (P<0.05) by panobinostat and to 46 days by BZ (P<0.05). The combination treatment further improved clinical outcome relative to both single-agent treatment groups (P<0.05), extending the TTE to 73 days. In contrast to BZ, the immunomodulatory drug thalidomide (TH) had no significant single-agent activity at 150 mg/kg p.o. qd for 4 weeks. However, combination activity (18% T/C) was observed when TH was combined with a sub-efficacious dose of panobinostat (5 mg/kg, 64% T/C). Combination of panobinostat and TH increased the TTE to 50 days, compared with 37.5, 43, and 39.5 days (P<0.05), respectively, for the vehicle, panobinostat, or TH as single agents. These data demonstrate that panobinostat exhibits significant anti-proliferative and anti-tumor activities on MM cells both in vitro and in vivo. Panobinostat, as a single agent or in combination with BZ or TH, is a promising therapy for MM, and these studies may provide the rationale for clinical evaluation of panobinostat and BZ combination in the treatment of MM.


2021 ◽  
Author(s):  
Mary E Law ◽  
Bradley J Davis ◽  
Amanda F Ghilardi ◽  
Elham Yaaghubi ◽  
Zaafir M Dulloo ◽  
...  

Tranexamic Acid (TA) is a clinically used antifibrinolytic that acts as a lysine mimetic to block binding of Plasminogen with Plasminogen activators, preventing conversion of Plasminogen to its proteolytically activated form, Plasmin. Previous studies suggested that TA may exhibit anticancer activity by blockade of extracellular Plasmin formation. Plasmin-mediated cleavage of the CDCP1 protein may increase its oncogenic functions through several downstream pathways. Results presented herein demonstrate that TA blocks Plasmin-mediated excision of the extracellular domain of the oncoprotein CDCP1. In vitro studies indicate that TA reduces the viability of a broad array of human and murine cancer cell lines, and breast tumor growth studies demonstrate that TA reduces cancer growth in vivo. Based on the ability of TA to mimic lysine and arginine, we hypothesized that TA may perturb multiple processes that involve Lys/Arg-rich protein sequences, and that TA may alter intracellular signaling pathways in addition to blocking extracellular Plasmin production. Indeed, TA-mediated suppression of tumor cell viability is associated with multiple biochemical actions, including inhibition of protein synthesis, reduced activating phosphorylation of STAT3 and S6K1, decreased expression of the MYC oncoprotein, and suppression of Lys acetylation. These findings suggest that TA or TA analogs may serve as lead compounds and inspire the production of new classes of anticancer agents that function by mimicking Lys and Arg.


2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi91-vi91
Author(s):  
Yu-Ting Su ◽  
Madison Butler ◽  
Lee Hwang ◽  
Dragan Maric ◽  
Shelton Earp ◽  
...  

Abstract BACKGROUND Glioblastoma-associated macrophages and microglia (GAMs) are the predominant immune cells in the tumor microenvironment. Activation of MerTK, a receptor tyrosine kinase, triggers efferocytosis and polarizes GAMs to an immunosuppressive phenotype, promoting glioma growth. Our previous findings showed that UNC2371, a small-molecule inhibitor of MerTK, induced a less immunosuppressive phenotype of GAMs. Here, we investigate the role of MerTK inhibition on glioblastoma cells in the tumor microenvironment in vitro and in vivo. METHODS Cytotoxicity of UNC2371 in glioblastoma cells was determined by cell viability and colony formation assays. The protein expression of MerTK, AKT, and Erk were quantified by Western blotting in UNC2371-treated glioblastoma cells. A syngeneic GL261 mouse orthotopic glioblastoma model was used to evaluate the survival benefit of UNC2371 treatment. Fluorescent multiplex immunohistochemistry (IHC) was used to evaluate the expression of CD206, an anti-inflammatory marker on GAMs in murine brain tumor tissues. RESULTS UNC2371 inhibited GBM cell growth with an EC50 < 100 nM in both human U251 and mouse GL261 glioma cells, but not in GAMs. UNC2371-induced cell death and decreased cell proliferation were demonstrated by colony formation assays. UNC2371 decreased protein expression of phosphorylated MerTK, AKT, and Erk, which are essential for cell survival signaling, in U251 and GL261 cells. Furthermore, UNC2371 treatment prolonged survival in the mouse orthotopic GL261 glioblastoma model, suggesting that UNC2371 induces glioma cell death. A decreased of CD206+ GAMs was found in mice glioma tissues by fluorescent multiplex IHC, consistent with our previous findings in the in vitro cell-based assays. These data suggest that in addition to alleviate immunosuppression in the glioma microenvironment, UNC2371 directly inhibits GBM cell growth in vitro and in vivo. CONCLUSION Our findings suggest that UNC2371 has a therapeutic benefit via promoting GAM polarization towards proinflammatory status in the glioblastoma microenvironment and unexpectedly, inducing tumor cell death.


2019 ◽  
Vol 127 ◽  
pp. 110-119 ◽  
Author(s):  
Islam M. El-Garawani ◽  
Waill A. Elkhateeb ◽  
Gihan M. Zaghlol ◽  
Rafa S. Almeer ◽  
Eman F. Ahmed ◽  
...  

2022 ◽  
Vol 12 ◽  
Author(s):  
Mary E. Law ◽  
Bradley J. Davis ◽  
Amanda F. Ghilardi ◽  
Elham Yaaghubi ◽  
Zaafir M. Dulloo ◽  
...  

Tranexamic Acid (TA) is a clinically used antifibrinolytic agent that acts as a Lys mimetic to block binding of Plasminogen with Plasminogen activators, preventing conversion of Plasminogen to its proteolytically activated form, Plasmin. Previous studies suggested that TA may exhibit anticancer activity by blockade of extracellular Plasmin formation. Plasmin-mediated cleavage of the CDCP1 protein may increase its oncogenic functions through several downstream pathways. Results presented herein demonstrate that TA blocks Plasmin-mediated excision of the extracellular domain of the oncoprotein CDCP1. In vitro studies indicate that TA reduces the viability of a broad array of human and murine cancer cell lines, and breast tumor growth studies demonstrate that TA reduces cancer growth in vivo. Based on the ability of TA to mimic Lys and Arg, we hypothesized that TA may perturb multiple processes that involve Lys/Arg-rich protein sequences, and that TA may alter intracellular signaling pathways in addition to blocking extracellular Plasmin production. Indeed, TA-mediated suppression of tumor cell viability is associated with multiple biochemical actions, including inhibition of protein synthesis, reduced activating phosphorylation of STAT3 and S6K1, decreased expression of the MYC oncoprotein, and suppression of Lys acetylation. Further, TA inhibited uptake of Lys and Arg by cancer cells. These findings suggest that TA or TA analogs may serve as lead compounds and inspire the production of new classes of anticancer agents that function by mimicking Lys and Arg.


Blood ◽  
2003 ◽  
Vol 102 (12) ◽  
pp. 4179-4186 ◽  
Author(s):  
Bing Z. Carter ◽  
Steven M. Kornblau ◽  
Twee Tsao ◽  
Rui-Yu Wang ◽  
Wendy D. Schober ◽  
...  

Abstract Survivin and XIAP, members of the protein family known as the inhibitors of apoptosis, interfere with the activation of caspases, called the “cell death executioners.” We examined Survivin (n = 116) and XIAP (n = 172) expression in primary acute myeloid leukemia (AML) blasts and assessed the impact of their expression on prognosis. They were detected in all samples analyzed. However, no correlation was observed with cytogenetics, remission attainment, or overall survival of patients with AML. To investigate the importance of caspases in chemotherapy-induced apoptosis in AML, we treated OCI-AML3 cells with Ara-C, doxorubicin, vincristine, and paclitaxel, which induced caspase cleavage and apoptosis. Blocking of caspase activation by pan-caspase inhibitor abolished poly(adenosine diphosphate [ADP]-ribose) polymerase cleavage and DNA fragmentation but did not prevent chemotherapy-induced cell death and did not inhibit, or only partially inhibited, mitochondrial release of cytochrome c, Smac, apoptosis-inducing factor (AIF), or loss of mitochondrial membrane potential. Caspase inhibition also did not protect AML blasts from chemotherapy-induced cell death in vitro. These results suggest that expression levels of Survivin or XIAP have no prognostic impact in AML patients. Although anticancer drugs induced caspase cleavage and apoptosis, cell killing was caspase independent. This may partially explain the lack of prognostic impact of XIAP and Survivin and may suggest caspase-independent mechanisms of cell death in AML. (Blood. 2003;102:4179-4186)


The role of vitamin D is implicated in carcinogenesis through numerous biological processes like induction of apoptosis, modulation of immune system inhibition of inflammation and cell proliferation and promotion of cell differentiation. Its use as additional adjuvant drug with cancer treatment may be novel combination for improved outcome of different cancers. Numerous preclinical, epidemiological and clinical studies support the role of vitamin D as an anticancer agent. Anticancer properties of vitamin D have been studied widely (both in vivo and in vitro) among various cancers and found to have promising results. There are considerable data that indicate synergistic potential of calcitriol and antitumor agents. Possible mechanisms for modulatory anticancer activity of vitamin D include its antiproliferative, prodifferentiating, and anti-angiogenic and apoptic properties. Calcitriol reduces invasiveness and metastatic potential of many cancer cells by inhibiting angiogenesis and regulating expression of the key molecules involved in invasion and metastasis. Anticancer activity of vitamin D is synergistic or additive with the antineoplastic actions of several drugs including cytotoxic chemotherapy agents like paclitaxel, docetaxel, platinum base compounds and mitoxantrone. Benefits of addition of vitamin D should be weighed against the risk of its toxicity.


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