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Pharmaceutics May 2021The aim of this work was to explore new therapeutic options against Chagas disease by the in vitro analysis of the biocidal activities of several tambjamine and...
The aim of this work was to explore new therapeutic options against Chagas disease by the in vitro analysis of the biocidal activities of several tambjamine and prodiginine derivatives, against the CLB strain (DTU TcVI). The compounds were initially screened against epimastigotes. The five more active compounds were assayed in intracellular forms. The tambjamine MM3 and both synthetic and natural prodigiosins displayed the highest trypanocidal profiles, with IC values of 4.52, 0.46, and 0.54 µM for epimastigotes and 1.9, 0.57, and 0.1 µM for trypomastigotes/amastigotes, respectively. Moreover, the combination treatment of these molecules with benznidazole showed no synergism. Finally, oxygen consumption inhibition determinations performed using high-resolution respirometry, revealed a potent effect of prodigiosin on parasite respiration (73% of inhibition at ½ IC), suggesting that its mode of action involves the mitochondria. Moreover, its promising selectivity index (50) pointed out an interesting trypanocidal potential and highlighted the value of prodigiosin as a new candidate to fight Chagas disease.
PubMed: 34065993
DOI: 10.3390/pharmaceutics13050705 -
Nan Fang Yi Ke Da Xue Xue Bao = Journal... Apr 2019To explore whether bortezomib and a Bcl-2 inhibitor exhibit synergistic anti-tumor effect in human acute T lymphoblastic leukemia cells.
OBJECTIVE
To explore whether bortezomib and a Bcl-2 inhibitor exhibit synergistic anti-tumor effect in human acute T lymphoblastic leukemia cells.
METHODS
MTT assay was used to determine the cytotoxicity of bortezomib in the absence or presence of Bcl-2 inhibitors (obatoclax, AT-101 and ABT-199) in Jurkat cells. The effects of drug treatment on the expression of Bcl-2 family proteins, LC3B, p62, ubiquitin, BiP/Grp78, p-JNK, p-p38 and CHOP proteins were examined by Western blotting. Flow cytometry was used to determine the effects of bortezomib and Bcl-2 inhibitors (obatoclax, AT-101 and ABT-199) on cell apoptosis. Quantitative real-time PCR was used to measure the mRNA expression levels of the key regulatory factors of unfolded protein reaction (UPR). A zebrafish xenograft model was used to study the anti-tumor effect of bortezomib, obatoclax and their combination in vivo.
RESULTS
Bortezomib or Bcl-2 inhibitors alone inhibited the cell viability of Jurkat cells, but only obatoclax and bortezomib showed synergistic cytotoxicity and pro-apoptotic effect. Obatoclax, rather than AT-101 and ABT- 199, blocked autophagic flux in the cells evidenced by concomitant accumulation of LC3B-Ⅱ and p62. Both bortezomib and obatoclax alone caused accumulation of polyubiquinated proteins, and their combination showed a synergistic effect, which was consistent with their synergistic cytotoxicity. The dual blockade of proteasome and autophagy by the combination of bortezomib and obatoclax triggered unfolded protein response followed by cell apoptosis. Preventing UPS dysfunction by tauroursodeoxycholic acid (TUDCA) significantly attenuated the cytotoxicity and pro-apoptotic effect of bortezomib in combination with obatoclax. In zebrafish xenograft models, bortezomib combined with obatoclax significantly decreased tumor foci formation.
CONCLUSIONS
Bortezomib and obatoclax for dual blockade of protein degradation pathways show synergistic anti-tumor effect in human acute T lymphoblastic leukemia cells.
Topics: Antineoplastic Agents; Apoptosis; Bortezomib; Cell Line, Tumor; Drug Synergism; Endoplasmic Reticulum Chaperone BiP; Humans; Indoles; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Proteolysis; Proto-Oncogene Proteins c-bcl-2; Pyrroles
PubMed: 31068282
DOI: 10.12122/j.issn.1673-4254.2019.04.04 -
Zhongguo Ying Yong Sheng Li Xue Za Zhi... May 2020To explore the effects of obatoclax(OBX) combined with gemcitabine(GEM) on breast cancer cells MCF-7 and BT-20 cell activity, migration, invasion and apoptosis under...
To explore the effects of obatoclax(OBX) combined with gemcitabine(GEM) on breast cancer cells MCF-7 and BT-20 cell activity, migration, invasion and apoptosis under hypoxia condition. Breast cancer cells MCF-7 and BT-20 were divided into normal group, hypoxia group, GEM group, OBX+GEM group. Normal group: Cells were cultured at 37℃, 5% CO for 24 h and 48 h; Hypoxia group: Cells were cultured at 37℃, 1% O, 5% CO, 94% N for 24 h and 48 h; GEM group: Cells were cultured at 37℃, 1% O, 5% CO, 94% N, adding 10 μmol/L GEM for 24 h and 48 h; OBX + GEM group: Cells were cultured at 37℃, 1% O, 5% CO, 94% N, adding 10 μmol/L GEM and 50 nmol/L OBX for 24 h and 48 h. Western blot method was used to detect the expressions of HIF-1α in MCF-7 and BT-20 cells under normal oxygen and hypoxia condition. CCK-8 method was used to detect cancer cell activity, each group was provided with 15 compound holes. Scratch experiment was used to detect cells migration ability, each group was provided with 6 compound holes. Western blot method was used to detect the expressions of vimentin, E-Cadherin and p53 protein in cells of each group. Under hypoxia condition, the expression of HIF-1α in MCF-7 and BT-20 cells was much higher than that under normal oxygen(P<0.05). Compared with hypoxia group, GEM could reduce MCF-7 and BT-20 cells migration ability(P<0.01)and cell activity(P<0.05), while decrease the expression of vimentin protein(P<0.01)and promote the expressions of E-Cadherin (P<0.01)and p53 protein(P<0.01) in tumor cells under hypoxia condition. In OBX combined with GEM group, the cell activity and the migration ability of MCF-7 and BT-20 were reduced significantly(P<0.01). The expression of vimentin in cells was further reduced(P<0.01). The expressions of E-Cadherin(P<0.01)and p53(P<0.01) protein were increased significantly compared with GEM group. Under hypoxia condition, OBX combined with a low-dose of GEM can significantly inhibit the growth, migration and invasion of breast cancer cells, and enhance the pro-apoptotic effect of GEM, but the specific mechanism needs further study.
Topics: Antineoplastic Agents; Breast Neoplasms; Cell Hypoxia; Cell Line, Tumor; Deoxycytidine; Gene Expression Regulation, Neoplastic; Humans; Indoles; Pyrroles; Gemcitabine
PubMed: 32981284
DOI: 10.12047/j.cjap.5955.2020.059 -
Scientific Reports Jun 2021Extracellular vesicles (EVs) are secreted from most cells and play important roles in cell-cell communication by transporting proteins, lipids, and nucleic acids. As the...
Extracellular vesicles (EVs) are secreted from most cells and play important roles in cell-cell communication by transporting proteins, lipids, and nucleic acids. As the involvement of EVs in diseases has become apparent, druggable regulators of EV secretion are required. However, the lack of a highly sensitive EV detection system has made the development of EV regulators difficult. We developed an ELISA system using a high-affinity phosphatidylserine-binder TIM4 to capture EVs and screened a 1567-compound library. Consequently, we identified one inhibitor and three activators of EV secretion in a variety of cells. The inhibitor, apoptosis activator 2, suppressed EV secretion via a different mechanism and had a broader cellular specificity than GW4869. Moreover, the three activators, namely cucurbitacin B, gossypol, and obatoclax, had broad cellular specificity, including HEK293T cells and human mesenchymal stem cells (hMSCs). In vitro bioactivity assays revealed that some regulators control EV secretion from glioblastoma and hMSCs, which induces angiogenesis and protects cardiomyocytes against apoptosis, respectively. In conclusion, we developed a high-throughput method to detect EVs with high sensitivity and versatility, and identified four compounds that can regulate the bioactivity of EVs.
Topics: Animals; Apoptosis; Drug Evaluation, Preclinical; Extracellular Vesicles; HCT116 Cells; HEK293 Cells; Humans; Jurkat Cells; K562 Cells; Mesenchymal Stem Cells; Mice; NIH 3T3 Cells; Small Molecule Libraries; THP-1 Cells
PubMed: 34188113
DOI: 10.1038/s41598-021-92860-2 -
Acta Pharmacologica Sinica Aug 2021Proteasome inhibitors, bortezomib (BTZ), and carfilzomib (CFZ) are approved drugs for hematological malignancies, but lack anticancer activities against most solid...
Proteasome inhibitors, bortezomib (BTZ), and carfilzomib (CFZ) are approved drugs for hematological malignancies, but lack anticancer activities against most solid tumors. Small cell lung cancer (SCLC) is a very aggressive neuroendocrine carcinoma of the lungs demanding effective therapy. In this study we investigated whether BTZ or CFZ combined with obatoclax (OBX), an antagonist for MCL-1 and a pan-BCL family inhibitor, could cause synergistic growth inhibition of SCLC cells. We showed that combined application of BTZ or CFZ with OBX caused synergistic growth inhibition of human SCLC cell lines (H82, H526, DMS79, H196, H1963, and H69) than single agent alone. Both BTZ-OBX and CFZ-OBX combinations displayed marked synergism on inducing apoptosis (~50% increase vs BTZ or CFZ alone). A comprehensive proteomics analysis revealed that BTZ preferentially induced the expression of MCL-1, an antiapoptotic protein, in SCLC cells. Thus, proteasome inhibitor-OBX combinations could specifically induce massive growth inhibition and apoptosis in SCLC cells. Subsequent proteome-wide profiling analysis of activated transcription factors suggested that BTZ- or CFZ-induced MCL-1 upregulation was transcriptionally driven by FOXM1. In nude mice bearing in SCLC H82 xenografts, both BTZ-OBX, and CFZ-OBX combinations exhibited remarkable antitumor activities against SCLC tumors evidenced by significant reduction of tumor size and the proliferation marker Ki-67 signals in tumor tissues as compared with single agent alone. Thus, proteasome inhibitor-OBX combinations are worth immediate assessments for SCLC in clinical settings.
Topics: Animals; Antineoplastic Agents; Apoptosis; Bortezomib; Cell Line, Tumor; Drug Synergism; Forkhead Box Protein M1; HEK293 Cells; Humans; Indoles; Lung Neoplasms; Mice, Nude; Myeloid Cell Leukemia Sequence 1 Protein; Oligopeptides; Proteasome Inhibitors; Pyrroles; Small Cell Lung Carcinoma; Up-Regulation; Xenograft Model Antitumor Assays; Mice
PubMed: 33139838
DOI: 10.1038/s41401-020-00544-w -
Translational Oncology Aug 2021Bcl-2 family proteins play critical roles in regulating lymphocyte development and maintain homeostasis, and have also been proved to be involved in various cancer types...
Bcl-2 family proteins play critical roles in regulating lymphocyte development and maintain homeostasis, and have also been proved to be involved in various cancer types development. However, the role of Bcl-2 in hepatocellular carcinoma (HCC) development has not been clearly studied. Here, we reported the pan-Bcl-2 inhibitor, obatoclax could directly inhibit HCC growth in vitro. We further demonstrated in murine HCC model that obatoclax also suppressed HCC development in vivo. We also proved that although obatoclax inhibited T cells expansion, it had no influence on T cells activation in vivo. Mechanism study revealed that obatoclax sensitized HCC cells to T cell-mediated killing. Combination therapy of obatoclax with anti-PD-1 antibody synergistically suppressed HCC development and prolonged the survival rate of tumor-bearing mice. The combination therapy promoted T cells activation and effector cytokines expression both in spleen and tumor. In summary, our results proved that obatoclax sensitized HCC cells to T cell -mediated killing. Combination of obatoclax with immune checkpoint blockade served as a promising therapeutic strategy for HCC treatment.
PubMed: 33975180
DOI: 10.1016/j.tranon.2021.101116 -
International Journal of Molecular... Dec 2016Colorectal cancer is the third most common cancer worldwide. Aberrant overexpression of antiapoptotic BCL-2 (B-cell lymphoma 2) family proteins is closely linked to...
Colorectal cancer is the third most common cancer worldwide. Aberrant overexpression of antiapoptotic BCL-2 (B-cell lymphoma 2) family proteins is closely linked to tumorigenesis and poor prognosis in colorectal cancer. Obatoclax is an inhibitor targeting all antiapoptotic BCL-2 proteins. A previous study has described the antiproliferative action of obatoclax in one human colorectal cancer cell line without elucidating the underlying mechanisms. We herein reported that, in a panel of human colorectal cancer cell lines, obatoclax inhibits cell proliferation, suppresses clonogenicity, and induces G₁-phase cell cycle arrest, along with cyclin D1 downregulation. Notably, ectopic cyclin D1 overexpression abrogated clonogenicity suppression but also G₁-phase arrest elicited by obatoclax. Mechanistically, pre-treatment with the proteasome inhibitor MG-132 restored cyclin D1 levels in all obatoclax-treated cell lines. Cycloheximide chase analyses further revealed an evident reduction in the half-life of cyclin D1 protein by obatoclax, confirming that obatoclax downregulates cyclin D1 through induction of cyclin D1 proteasomal degradation. Lastly, threonine 286 phosphorylation of cyclin D1, which is essential for initiating cyclin D1 proteasomal degradation, was induced by obatoclax in one cell line but not others. Collectively, we reveal a novel anticancer mechanism of obatoclax by validating that obatoclax targets cyclin D1 for proteasomal degradation to downregulate cyclin D1 for inducing antiproliferation.
Topics: Carcinoma; Cell Proliferation; Colorectal Neoplasms; Cyclin D1; Down-Regulation; G1 Phase Cell Cycle Checkpoints; HCT116 Cells; HT29 Cells; Humans; Indoles; Proteolysis; Proto-Oncogene Proteins c-bcl-2; Pyrroles
PubMed: 28035994
DOI: 10.3390/ijms18010044 -
Journal of Translational Medicine Mar 2024Colorectal cancer (CRC) is the third most prevalent cancer globally, and liver metastasis (CRLM) is the primary cause of death. Hence, it is essential to discover novel...
BACKGROUND
Colorectal cancer (CRC) is the third most prevalent cancer globally, and liver metastasis (CRLM) is the primary cause of death. Hence, it is essential to discover novel prognostic biomarkers and therapeutic drugs for CRLM.
METHODS
This study developed two liver metastasis-associated prognostic signatures based on differentially expressed genes (DEGs) in CRLM. Additionally, we employed an interpretable deep learning model utilizing drug sensitivity databases to identify potential therapeutic drugs for high-risk CRLM patients. Subsequently, in vitro and in vivo experiments were performed to verify the efficacy of these compounds.
RESULTS
These two prognostic models exhibited superior performance compared to previously reported ones. Obatoclax, a BCL-2 inhibitor, showed significant differential responses between high and low risk groups classified by prognostic models, and demonstrated remarkable effectiveness in both Transwell assay and CT26 colorectal liver metastasis mouse model.
CONCLUSIONS
This study highlights the significance of developing specialized prognostication approaches and investigating effective therapeutic drugs for patients with CRLM. The application of a deep learning drug response model provides a new drug discovery strategy for translational medicine in precision oncology.
Topics: Animals; Mice; Humans; Precision Medicine; Prognosis; Liver Neoplasms; Drug Discovery; Colorectal Neoplasms
PubMed: 38555418
DOI: 10.1186/s12967-024-05127-5 -
Cancer Science Feb 2022Several lines of research suggest that Bcl-xL-mediated anti-apoptotic effects may contribute to the pathogenesis of myeloproliferative neoplasms driven by JAK2V617F and...
Several lines of research suggest that Bcl-xL-mediated anti-apoptotic effects may contribute to the pathogenesis of myeloproliferative neoplasms driven by JAK2V617F and serve as therapeutic target. Here, we used a knock-in JAK2V617F mouse model and confirmed that Bcl-xL was overexpressed in erythroid progenitors. The myeloproliferative neoplasm (MPN)-induced phenotype in the peripheral blood by conditional knock-in of JAK2V617F was abrogated by conditional knockout of Bcl2l1, which presented anemia and thrombocytopenia independently of JAK2 mutation status. Mx1-Cre Jak2V617 /Bcl2l1 mice presented persistent splenomegaly as a result of extramedullary hematopoiesis and pro-apoptotic stimuli in terminally differentiated erythroid progenitors. The pan-BH3 mimetic inhibitor obatoclax showed superior cytotoxicity in JAK2V617F cell models, and reduced clonogenic capacity in ex vivo assay using Vav-Cre Jak2V617F bone marrow cells. Both ruxolitinib and obatoclax significantly reduced spleen weights in a murine Jak2V617F MPN model but did not show additive effect. The tumor burden reduction was observed with either ruxolitinib or obatoclax in terminal differentiation stage neoplastic cells but not in myeloid-erythroid precursors. Therefore, disrupting the BCL2 balance is not sufficient to treat MPN at the stem cell level, but it is certainly an additional option for controlling the critical myeloid expansion of the disease.
Topics: Animals; Cell Line, Tumor; Cell Proliferation; Cell Survival; Disease Models, Animal; Drug Resistance, Neoplasm; Enzyme Inhibitors; Erythroid Precursor Cells; Humans; Indoles; Janus Kinase 2; Mice; Mutation; Myeloproliferative Disorders; Nitriles; Proto-Oncogene Proteins c-bcl-2; Pyrazoles; Pyrimidines; Pyrroles; Tumor Burden; bcl-X Protein
PubMed: 34808021
DOI: 10.1111/cas.15210 -
PloS One 2014An open-label phase I/II study of single-agent obatoclax determined a maximum tolerated dose (MTD) and schedule, safety, and efficacy in older patients (≥ 70 yr) with... (Randomized Controlled Trial)
Randomized Controlled Trial
PURPOSE
An open-label phase I/II study of single-agent obatoclax determined a maximum tolerated dose (MTD) and schedule, safety, and efficacy in older patients (≥ 70 yr) with untreated acute myeloid leukemia (AML).
EXPERIMENTAL DESIGN
Phase I evaluated the safety of obatoclax infused for 3 hours on 3 consecutive days (3 h × 3 d) in 2-week cycles. Initial obatoclax dose was 30 mg/day (3 h × 3 d; n = 3). Obatoclax was increased to 45 mg/day (3 h × 3 d) if ≤ 1 patient had a dose-limiting toxicity (DLT) and decreased to 20 mg/day (3 h × 3 d) if DLT occurred in ≥ 2 patients. In the phase II study, 12 patients were randomized to receive obatoclax at the dose identified during phase I (3 h × 3 d) or 60 mg/day administered by continuous infusion over 24 hours for 3 days (24 h × 3 d) to determine the morphologic complete response rate.
RESULTS
In phase I, two of three patients receiving obatoclax 30 mg/day (3 h × 3 d) experienced grade 3 neurologic DLTs (confusion, ataxia, and somnolence). Obatoclax was decreased to 20 mg/day (3 h × 3 d). In phase II, no clinically relevant safety differences were observed between the 20 mg/day (3 h × 3 d; n = 7) and 60 mg/day (24 h × 3 d; n = 5) arms. Neurologic and psychiatric adverse events were most common and were generally transient and reversible. Complete response was not achieved in any patient.
CONCLUSIONS
Obatoclax 20 mg/day was the MTD (3 h × 3 d) in older patients with AML. In the schedules tested, single-agent obatoclax was not associated with an objective response. Evaluation in additional subgroups or in combination with other chemotherapy modalities may be considered for future study.
TRIAL REGISTRATION
ClinicalTrials.gov NCT00684918.
Topics: Aged; Aged, 80 and over; Blast Crisis; Demography; Drug Administration Schedule; Female; Humans; Indoles; Leukemia, Myeloid, Acute; Male; Neutrophils; Platelet Count; Pyrroles; Treatment Outcome
PubMed: 25285531
DOI: 10.1371/journal.pone.0108694