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Current Hematologic Malignancy Reports Jan 2010Despite advances in treatment, chronic lymphocytic leukemia (CLL) remains incurable with standard therapies. Novel therapeutic agents are needed, particularly for... (Review)
Review
Despite advances in treatment, chronic lymphocytic leukemia (CLL) remains incurable with standard therapies. Novel therapeutic agents are needed, particularly for patients with high-risk cytogenetic abnormalities such as del(17p13). The past year has seen several advances in this field. The immunomodulatory drug lenalidomide and the cyclin-dependent kinase inhibitor flavopiridol demonstrated clinical activity in fludarabine-refractory CLL patients with high-risk cytogenetic features and bulky lymphadenopathy, but they were associated with toxicities such as tumor flare and tumor lysis. Second-generation monoclonal anti-CD20 antibodies in clinical trials include ofatumumab, which demonstrated activity in fludarabine-refractory patients with bulky lymphadenopathy. Oblimersen, obatoclax, and ABT-263 target the antiapoptotic protein Bcl-2. Investigational agents with novel therapeutic targets include the anti-CD37 small modular immunopharmaceutical TRU-016, the oral spleen tyrosine kinase (Syk) inhibitor fostamatinib, and the oral phosphatidylinositol-3-kinase (PI3K) inhibitor CAL-101; all of these have all shown preliminary evidence of clinical activity. The development of novel agents for treating CLL remains an active, exciting area of research.
Topics: Antibodies, Monoclonal; Antineoplastic Agents; Clinical Trials, Phase I as Topic; Clinical Trials, Phase II as Topic; Drug Delivery Systems; Drugs, Investigational; Flavonoids; Humans; Immunologic Factors; Lenalidomide; Leukemia, Lymphocytic, Chronic, B-Cell; Neoplasm Proteins; Piperidines; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-bcl-2; Thalidomide
PubMed: 20425394
DOI: 10.1007/s11899-009-0039-9 -
Cell Death & Disease Apr 2022Atypical teratoid/rhabdoid tumors (AT/RT) are the most common malignant brain tumors of infancy and have a dismal 4-year event-free survival (EFS) of 37%. We have...
Atypical teratoid/rhabdoid tumors (AT/RT) are the most common malignant brain tumors of infancy and have a dismal 4-year event-free survival (EFS) of 37%. We have previously shown that mTOR activation contributes to AT/RT's aggressive growth and poor survival. Targeting the mTOR pathway with the dual mTORC1/2 inhibitor TAK-228 slows tumor growth and extends survival in mice bearing orthotopic xenografts. However, responses are primarily cytostatic with limited durability. The aim of this study is to understand the impact of mTOR inhibitors on AT/RT signaling pathways and design a rational combination therapy to drive a more durable response to this promising therapy. We performed RNASeq, gene expression studies, and protein analyses to identify pathways disrupted by TAK-228. We find that TAK-228 decreases the expression of the transcription factor NRF2 and compromises AT/RT cellular defenses against oxidative stress and apoptosis. The BH3 mimetic, Obatoclax, is a potent inducer of oxidative stress and apoptosis in AT/RT. These complementary mechanisms of action drive extensive synergies between TAK-228 and Obatoclax slowing AT/RT cell growth and inducing apoptosis and cell death. Combination therapy activates the integrative stress response as determined by increased expression of phosphorylated EIF2α, ATF4, and CHOP, and disrupts the protective NOXA.MCL-1.BIM axis, forcing stressed cells to undergo apoptosis. Combination therapy is well tolerated in mice bearing orthotopic xenografts of AT/RT, slows tumor growth, and extends median overall survival. This novel combination therapy could be added to standard upfront therapies or used as a salvage therapy for relapsed disease to improve outcomes in AT/RT.
Topics: Animals; Humans; Indoles; Mechanistic Target of Rapamycin Complex 1; Mice; Pyrroles; Rhabdoid Tumor; TOR Serine-Threonine Kinases
PubMed: 35484114
DOI: 10.1038/s41419-022-04868-9 -
PloS One 2013Anti-apoptotic Bcl-2 family proteins, in particular, Mcl-1, are known to play a critical role in resistance of human melanoma cells to induction of apoptosis by...
Anti-apoptotic Bcl-2 family proteins, in particular, Mcl-1, are known to play a critical role in resistance of human melanoma cells to induction of apoptosis by endoplasmic reticulum stress and other agents. The present study examined whether the BH3 mimetics, Obatoclax and ABT-737, which inhibit multiple anti-apoptotic Bcl-2 family proteins, would overcome resistance to apoptosis. We report that both agents induced a strong unfolded protein response (UPR) and that RNAi knockdown of UPR signalling proteins ATF6, IRE1α and XBP-1 inhibited Mcl-1 upregulation and increased sensitivity to the agents. These results demonstrate that inhibition of anti-apoptotic Bcl-2 proteins by Obatoclax and ABT-737 appears to elicit a protective feedback response in melanoma cells, by upregulation of Mcl-1 via induction of the UPR. We also report that Obatoclax, but not ABT-737, strongly induces autophagy, which appears to play a role in determining melanoma sensitivity to the agents.
Topics: Antineoplastic Agents; Apoptosis; Autophagy; Biphenyl Compounds; Calcium; Cell Line, Tumor; Cytosol; Drug Resistance, Neoplasm; Endoplasmic Reticulum Stress; Humans; Indoles; Melanoma; Myeloid Cell Leukemia Sequence 1 Protein; Nitrophenols; Piperazines; Proto-Oncogene Proteins c-bcl-2; Pyrroles; Sulfonamides; Unfolded Protein Response; Up-Regulation
PubMed: 24367627
DOI: 10.1371/journal.pone.0084073 -
Molecular Pharmacology May 2012Prior studies in breast cancer cells have shown that lapatinib and obatoclax interact in a greater than additive fashion to cause cell death and do so through a toxic...
Prior studies in breast cancer cells have shown that lapatinib and obatoclax interact in a greater than additive fashion to cause cell death and do so through a toxic form of autophagy. The present studies sought to extend our analyses to the central nervous system (CNS) tumor cells and to further define mechanisms of drug action. Lapatinib and obatoclax killed multiple CNS tumor isolates. Cells lacking PTEN (phosphatase and tensin homolog on chromosome 10) function were relatively resistant to drug combination lethality; expression of PTEN in PTEN-null cells restored drug sensitivity, and knockdown of PTEN promoted drug resistance. On the basis of knockdown of ERBB1-4 (erythroblastic leukemia viral oncogene homolog 1-4), we discovered that the inhibition of ERBB1/3/4 receptors were most important for enhancing obatoclax lethality rather than ERBB2. In parallel, we noted in CNS tumor cells that knockdown of BCL-xL (B-cell lymphoma-extra large)and MCL-1 (myeloid cell leukemia-1) interacted in an additive fashion to facilitate lapatinib lethality. Pretreatment of tumor cells with obatoclax enhanced the lethality of lapatinib to a greater extent than concomitant treatment. Treatment of animals carrying orthotopic CNS tumor isolates with lapatinib- and obatoclax-prolonged survival. Altogether, our data show that lapatinib and obatoclax therapy could be of use in the treatment of tumors located in the CNS.
Topics: Antineoplastic Agents; Autophagy; Cell Line, Tumor; ErbB Receptors; Humans; Indoles; Lapatinib; Myeloid Cell Leukemia Sequence 1 Protein; Neoplasms; PTEN Phosphohydrolase; Proto-Oncogene Proteins c-bcl-2; Pyrroles; Quinazolines; Receptor, ErbB-3; Receptor, ErbB-4; bcl-X Protein
PubMed: 22357666
DOI: 10.1124/mol.112.077586 -
Methods and Findings in Experimental... 2008Gateways to Clinical Trials are a guide to the most recent clinical trials in current literature and congresses. The data in the following tables has been retrieved from...
Gateways to Clinical Trials are a guide to the most recent clinical trials in current literature and congresses. The data in the following tables has been retrieved from the Clinical Trials Knowledge Area of Prouse Science Integrity, the drug discovery and development portal, http://integrity.prous.com. This issue focuses on the following selection of drugs: 101M, 3F8; Abatacept, ABT-263, Adalimumab, AG-7352, Agatolimod sodium, Alfimeprase, Aliskiren fumarate, Alvimopan hydrate, Aminolevulinic acid hexyl ester, Ammonium tetrathiomolybdate, Anakinra, Aripiprazole, AS-1404, AT-9283, Atomoxetine hydrochloride, AVE-1642, AVE-9633, Axitinib, AZD-0530; Becocalcidiol, Belotecan hydrochloride, Bevacizumab, BG-9928, BIBF-1120, BMS-275183, Bortezomib, Bosentan; Catumaxomab, Cetuximab, CHR-2797, Ciclesonide, Clevidipine, Cypher, Cytarabine/daunorubicin; Darifenacin hydrobromide, Darunavir, Denosumab, Desvenlafaxine succinate, Disufenton sodium, Duloxetine hydrochloride, Dutasteride; Eculizumab, Efalizumab, Eicosapentaenoic acid/docosahexaenoic acid, Eplerenone, Epratuzumab, Erlotinib hydrochloride, Escitalopram oxalate, Ethynylcytidine, Etravirine, Everolimus, Ezetimibe; Fulvestrant; Garenoxacin mesilate, Gefitinib, Gestodene; HI-164, Hydralazine hydrochloride/isosorbide dinitrate; Icatibant acetate, ICX-RHY, Idraparinux sodium, Indacaterol, Ispronicline, Ivabradine hydrochloride, Ixabepilone; KB-2115, KW-2449; L-791515, Lapatinib ditosylate, LGD-4665, Licofelone, Liposomal doxorubicin, Lisdexamfetamine mesilate, Lumiracoxib; Methoxy polyethylene glycol-epoetin-beta, Miglustat, Mipomersen sodium, Mitumprotimut-T, MK-0822A, MK-0974; Nelarabine; Obatoclax mesylate, Olmesartan medoxomil, Olmesartan medoxomil/hydrochlorothiazide; Paliperidone, Palonosetron hydrochloride, Panitumumab, Pegfilgrastim, Peginterferon alfa-2a, Pemetrexed disodium, Perospirone hydrochloride, Pertuzumab, Pimecrolimus, Pitrakinra, Pixantrone maleate, Posaconazole, Pregabalin; Quercetin; RALGA, Raltegravir potassium, Ranelic acid distrontium salt, rhHistone 1.3, Rimonabant, Rivaroxaban, Rosuvastatin calcium, RTS,S/SBAS2; Satraplatin, SNDX-275, Sodium butyrate, Solifenacin succinate, Sorafenib, SU-14813, Sunitinib malate; Tadalafil, Tafenoquine succinate, Tamatinib fosdium, Taxus, Telbivudine, Telmisartan/hydrochlorothiazide, Temsirolimus, Tiotropium bromide, Tipranavir, Tocilizumab, Trabectedin, Tramadol hydrochloride/acetaminophen; Ulipristal acetate, Uracil, Ursodeoxycholyltaurine; Valdecoxib, Vardenafil hydrochloride hydrate, Varenicline tartrate, Vildagliptin, Vinflunine, Vitespen, Vorinostat; ZK-EPO, Zoledronic acid monohydrate.
Topics: Clinical Trials as Topic; Humans
PubMed: 18389098
DOI: No ID Found -
Drug News & Perspectives Mar 2008
Topics: Antineoplastic Agents; Controlled Clinical Trials as Topic; Humans; Hydrazines; Indoles; Melanoma; Neoplasm Metastasis; Neoplasms; Pyrroles
PubMed: 18389103
DOI: No ID Found -
European Journal of Cell Biology Dec 2017BH3-only proteins constitute major proportion of pro-apoptotic members of B-cell lymphoma 2 (Bcl-2) family of apoptotic regulatory proteins and participate in embryonic... (Review)
Review
BH3-only proteins constitute major proportion of pro-apoptotic members of B-cell lymphoma 2 (Bcl-2) family of apoptotic regulatory proteins and participate in embryonic development, tissue homeostasis and immunity. Absence of BH3-only proteins contributes to autoimmune disorders and tumorigenesis. Bim (Bcl-2 Interacting Mediator of cell death), most important member of BH3-only proteins, shares a BH3-only domain (9-16 aa) among 4 domains (BH1-BH4) of Bcl-2 family proteins and highly pro-apoptotic in nature. Bim initiates the intrinsic apoptotic pathway under both physiological and patho-physiological conditions. Reduction in Bim expression was found to be associated with tumor promotion and autoimmunity, while overexpression inhibited tumor growth and drug resistance as cancer cells suppress Bim expression and stability. Apart from its role in normal homeostasis, Bim has emerged as a central player in regulation of tumorigenesis, therefore gaining attention as a plausible target for chemotherapy. Regulation of Bim expression and stability is complicated and regulated at multiple levels viz. transcriptional, post-transcriptional, post-translational (preferably by phosphorylation and ubiquitination), epigenetic (by promoter acetylation or methylation) including miRNAs. Furthermore, control over Bim expression and stability may be exploited to enhance chemotherapeutic efficacy, overcome drug resistance and select anticancer drug regimen as various chemotherapeutic agents exploit Bim as an executioner of cell death. Owing to its potent anti-tumorigenic activity many BH3 mimetics e.g. ABT-737, ABT-263, obatoclax, AT-101and A-1210477 have been developed and entered in clinical trials. It is more likely that in near future strategies commanding Bim expression and stability ultimately lead to Bim based therapeutic regimen for cancer treatment.
Topics: Animals; Antineoplastic Agents; Bcl-2-Like Protein 11; Humans; Molecular Targeted Therapy; Peptide Fragments; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-bcl-2
PubMed: 29100606
DOI: 10.1016/j.ejcb.2017.09.002 -
Electrophoresis Aug 2017Inherent electrical properties of cells can be beneficial to characterize different cell lines and their response to experimental drugs. This paper presents a novel...
Inherent electrical properties of cells can be beneficial to characterize different cell lines and their response to experimental drugs. This paper presents a novel method to characterize the response of breast cancer cells to drug stimuli through use of off-chip passivated-electrode insulator-based dielectrophoresis (OπDEP) and the application of AC electric fields. This work is the first to demonstrate the ability of OπDEP to differentiate between two closely related breast cancer cell lines, LCC1 and LCC9 while assessing their drug sensitivity to an experimental anti-cancer agent, Obatoclax. Although both cell lines are derivatives of estrogen-responsive MCF-7 breast cancer cells, growth of LCC1 is estrogen independent and anti-estrogen responsive, while LCC9 is both estrogen-independent and anti-estrogen resistant. Under the same operating conditions, LCC1 and LCC9 had different DEP profiles. LCC1 cells had a trapping onset (crossover) frequency of 700 kHz and trapping efficiencies between 30-40%, while LCC9 cells had a lower crossover frequency (100 kHz) and showed higher trapping efficiencies of 40-60%. When exposed to the Obatoclax, both cell lines exhibited dose-dependent shifts in DEP crossover frequency and trapping efficiency. Here, DEP results supplemented with cell morphology and proliferation assays help us to understand the response of these breast cancer cells to Obatoclax.
Topics: Antineoplastic Agents; Breast Neoplasms; Cell Proliferation; Cell Size; Drug Resistance, Neoplasm; Electrodes; Electrophoresis; Estrogen Antagonists; Female; Humans; Indoles; MCF-7 Cells; Microfluidic Analytical Techniques; Pyrroles
PubMed: 28608427
DOI: 10.1002/elps.201600447 -
Advances in Medicine 2014Due to their central role in the regulation of apoptosis, the antiapoptotic BCL2-proteins are highly promising targets for the development of novel anticancer... (Review)
Review
Due to their central role in the regulation of apoptosis, the antiapoptotic BCL2-proteins are highly promising targets for the development of novel anticancer treatments. To this end, several strategies have been developed to inhibit BCL2, BCL-XL, BCL-w, and MCL1. While early clinical trials in haematological malignancies demonstrated exciting single-agent activity of BCL2-inhibitors, the response in solid tumours was limited, indicating that, in solid tumours, different strategies have to be developed in order to successfully treat patients with BCL2-inhibitors. In this review, the function of the different antiapoptotic BCL2-proteins and their role in solid tumours will be discussed. In addition, a comprehensive analysis of current small molecules targeting these antiapoptotic BCL2-proteins (e.g., ABT-737, ABT-263, ABT-199, TW-37, sabutoclax, obatoclax, and MIM1) will be provided including a discussion of the results of any clinical trials. This analysis will summarise the potential of BCL2-inhibitors for the treatment of solid tumours and will unravel novel approaches to utilise these inhibitors in clinical applications.
PubMed: 26556430
DOI: 10.1155/2014/943648 -
Viruses Sep 2020Zika virus (ZIKV) was identified in 1947 in the Zika forest of Uganda and it has emerged recently as a global health threat, with recurring outbreaks and its...
Zika virus (ZIKV) was identified in 1947 in the Zika forest of Uganda and it has emerged recently as a global health threat, with recurring outbreaks and its associations with congenital microcephaly through maternal fetal transmission and Guillain-Barré syndrome. Currently, there are no United States (US) Food and Drug Administration (FDA)-approved vaccines or antivirals to treat ZIKV infections, which underscores an urgent medical need for the development of disease intervention strategies to treat ZIKV infection and associated disease. Drug repurposing offers various advantages over developing an entirely new drug by significantly reducing the timeline and resources required to advance a candidate antiviral into the clinic. Screening the ReFRAME library, we identified ten compounds with antiviral activity against the prototypic mammarenavirus lymphocytic choriomeningitis virus (LCMV). Moreover, we showed the ability of these ten compounds to inhibit influenza A and B virus infections, supporting their broad-spectrum antiviral activity. In this study, we further evaluated the broad-spectrum antiviral activity of the ten identified compounds by testing their activity against ZIKV. Among the ten compounds, Azaribine (SI-MTT = 146.29), AVN-944 (SI-MTT = 278.16), and Brequinar (SI-MTT = 157.42) showed potent anti-ZIKV activity in post-treatment therapeutic conditions. We also observed potent anti-ZIKV activity for Mycophenolate mofetil (SI-MTT = 20.51), Mycophenolic acid (SI-MTT = 36.33), and AVN-944 (SI-MTT = 24.51) in pre-treatment prophylactic conditions and potent co-treatment inhibitory activity for Obatoclax (SI-MTT = 60.58), Azaribine (SI-MTT = 91.51), and Mycophenolate mofetil (SI-MTT = 73.26) in co-treatment conditions. Importantly, the inhibitory effect of these compounds was strain independent, as they similarly inhibited ZIKV strains from both African and Asian/American lineages. Our results support the broad-spectrum antiviral activity of these ten compounds and suggest their use for the development of antiviral treatment options of ZIKV infection.
Topics: A549 Cells; Animals; Antiviral Agents; Apoptosis; Azauridine; Biphenyl Compounds; Carbamates; Cell Survival; Chlorocebus aethiops; Drug Repositioning; Guillain-Barre Syndrome; Humans; Microcephaly; Phenylurea Compounds; Uganda; Vero Cells; Virus Replication; Zika Virus; Zika Virus Infection
PubMed: 32961956
DOI: 10.3390/v12091041