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Biomaterials Jul 2018Most ovarian cancer patients respond well to initial platinum-based chemotherapy. However, within a year, many patients experience disease recurrence with a platinum...
Most ovarian cancer patients respond well to initial platinum-based chemotherapy. However, within a year, many patients experience disease recurrence with a platinum resistant phenotype that responds poorly to second line chemotherapies. As a result, new strategies to address platinum resistant ovarian cancer (PROC) are needed. Herein, we report that NP co-delivery of cisplatin (CP) and wortmannin (Wtmn), a DNA repair inhibitor, synergistically enhances chemoradiotherapy (CRT) and reverses CP resistance in PROC. We encapsulated this regimen in FDA approved poly(lactic-co-glycolic acid)-poly(ethylene glycol) (PLGA-PEG) NPs to reduce systemic side effects, enhance cellular CP uptake, improve Wtmn stability, and increase therapeutic efficacy. Treatment of platinum-sensitive ovarian cancer (PSOC) and PROC murine models with these dual-drug loaded NPs (DNPs) significantly reduced tumor burden versus treatment with combinations of free drugs or single-drug loaded NPs (SNPs). These results support further investigation of this NP-based, synergistic drug regimen as a means to combat PROC in the clinic.
Topics: Animals; Antineoplastic Agents; Cell Line, Tumor; Chemoradiotherapy; Cisplatin; Drug Carriers; Drug Synergism; Female; Humans; Mice; Nanoparticles; Ovarian Neoplasms; Polyesters; Polyethylene Glycols; Wortmannin; Xenograft Model Antitumor Assays
PubMed: 29631163
DOI: 10.1016/j.biomaterials.2018.03.055 -
Aging Jan 2022Autophagy is an important regulator of cellular homeostasis and its dysregulation often results in cancer. Aberrant glycosylation induced by oncogenic transformation...
Autophagy is an important regulator of cellular homeostasis and its dysregulation often results in cancer. Aberrant glycosylation induced by oncogenic transformation contributes to tumor invasion and metastasis. In a previous study, we have demonstrated that EpCAM, a glycosylation protein, is associated with cell growth and metastasis in breast cancer. But the effect of EpCAM glycosylation on autophagy is not clear. the precise mechanism of regulation remains largely unknown. In this study, breast cancer cells were transfected with N-glycosylation mutation EpCAM plasmid to express deglycosylated EpCAM. The result showed that deglycosylated EpCAM promoted autophagy in breast cancer cells. We further confirmed this conclusion with the activator (Rapamycin, RAP) and inhibitor (Wortmannin) of autophagy. We also found that deglycosylated EpCAM promoted apoptosis and inhibited proliferation through activating autophagy by suppressing Akt/mTOR signaling pathway in breast cancer cells. These findings represent a novel mechanism by which deglycosylated EpCAM inhibits proliferation by enhancing autophagy of breast cancer cells via PI3K/Akt/mTOR pathway. In conclusion, the combination of autophagy modulation and EpCAM targeted therapy is a promising therapeutic strategy in the treatment of breast cancer.
Topics: Antifungal Agents; Autophagy; Biomarkers; Breast Neoplasms; Cell Line, Tumor; Cell Proliferation; Epithelial Cell Adhesion Molecule; Female; Gene Expression Regulation, Neoplastic; Gene Silencing; Heterocyclic Compounds, 3-Ring; Humans; Phosphatidylinositol 3-Kinases; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-akt; Sirolimus; TOR Serine-Threonine Kinases; Wortmannin
PubMed: 34983878
DOI: 10.18632/aging.203795 -
Bioscience Reports Oct 2020The present study was to determine the roles of Angiotensin (Ang) II in the growth of lymphoma in nude mice and the proliferation and viability of the human Natural...
The present study was to determine the roles of Angiotensin (Ang) II in the growth of lymphoma in nude mice and the proliferation and viability of the human Natural Killer/T (NK/T)-cell lymphoma cell line SNK-6, and the activation of downstream signaling pathway. Lymphoma samples and corresponding normal tissues were obtained from lymphoma patients. Proliferation of SNK-6 cells was detected by CCK8 or MTT assay. The levels of Ang II and its receptor Ang II type 1 receptor (AT1R) were higher in lymphoma tissues than those in control tissues. Ang II increased the lymphoma volume and size in nude mice, the proliferation and viability and the proliferating cell nuclear antigen (PCNA) and Ki67 levels of SNK-6 cells. Losartan, an antagonist of AT1R, reduced lymphoma volume and size in nude mice, and the proliferation and viability and the PCNA and Ki67 levels of SNK-6 cells. The levels of phosphorylated phosphatidylinositol 3-kinase (p-PI3K) and phosphorylated protein kinase B (p-Akt) were increased by Ang II and then reduced by losartan in SNK-6 cells. The proliferation and viability of SNK-6 cells were increased by Ang II, but these increases were inhibited by PI3K inhibitor wortmannin and Akt inhibitor MK2206. The increases of PCNA and Ki67 induced by Ang II were inhibited by wortmannin or MK2206 in SNK-6 cells. These results indicate that Ang II/AT1R is activated in lymphoma, and Ang II promotes the progression of lymphoma in nude mice and the proliferation and viability of SNK-6 cells via activating PI3K/Akt signaling pathway.
Topics: Aged; Angiotensin II; Angiotensin II Type 1 Receptor Blockers; Antineoplastic Combined Chemotherapy Protocols; Cell Line, Tumor; Cell Proliferation; Cell Survival; Female; Heterocyclic Compounds, 3-Ring; Humans; Losartan; Lymph Nodes; Lymphoma, Extranodal NK-T-Cell; Male; Middle Aged; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Proto-Oncogene Proteins c-akt; Receptor, Angiotensin, Type 1; Signal Transduction; Wortmannin; Xenograft Model Antitumor Assays
PubMed: 32969473
DOI: 10.1042/BSR20202388 -
Clinical Microbiology Reviews Oct 1999Recent evolutionary studies reveal that microorganisms including yeasts and fungi are more closely related to mammals than was previously appreciated. Possibly as a... (Review)
Review
Recent evolutionary studies reveal that microorganisms including yeasts and fungi are more closely related to mammals than was previously appreciated. Possibly as a consequence, many natural-product toxins that have antimicrobial activity are also toxic to mammalian cells. While this makes it difficult to discover antifungal agents without toxic side effects, it also has enabled detailed studies of drug action in simple genetic model systems. We review here studies on the antifungal actions of antineoplasmic agents. Topics covered include the mechanisms of action of inhibitors of topoisomerases I and II; the immunosuppressants rapamycin, cyclosporin A, and FK506; the phosphatidylinositol 3-kinase inhibitor wortmannin; the angiogenesis inhibitors fumagillin and ovalicin; the HSP90 inhibitor geldanamycin; and agents that inhibit sphingolipid metabolism. In general, these natural products inhibit target proteins conserved from microorganisms to humans. These studies highlight the potential of microorganisms as screening tools to elucidate the mechanisms of action of novel pharmacological agents with unique effects against specific mammalian cell types, including neoplastic cells. In addition, this analysis suggests that antineoplastic agents and derivatives might find novel indications in the treatment of fungal infections, for which few agents are presently available, toxicity remains a serious concern, and drug resistance is emerging.
Topics: Acyltransferases; Androstadienes; Angiogenesis Inhibitors; Animals; Antifungal Agents; Antineoplastic Agents; Cisplatin; Cyclosporine; Estrogen Antagonists; Humans; Sirolimus; Sphingolipids; Tacrolimus; Topoisomerase I Inhibitors; Wortmannin
PubMed: 10515904
DOI: 10.1128/CMR.12.4.583 -
Journal of Andrology 2004Sperm capacitation is regulated by multiple pathways that also control sperm motility and tyrosine (Tyr) phosphorylation of several sperm proteins. Among the reported...
Inhibitors of phosphoinositide 3-kinase, LY294002 and wortmannin, affect sperm capacitation and associated phosphorylation of proteins differently: Ca2+-dependent divergences.
Sperm capacitation is regulated by multiple pathways that also control sperm motility and tyrosine (Tyr) phosphorylation of several sperm proteins. Among the reported pathways, phosphoinositide 3-kinase (PI3K) signaling and its role in modulating sperm postejaculatory changes and motility remain elusive. It was shown that wortmannin, a selective inhibitor of PI3K, prevents human sperm acrosome reaction. Using LY294002 (2-(4-morphlinyl)-8-phenyl-4H-1-benzopyran-4-one), another chemically different inhibitor of PI3K, it was suggested that this enzyme inhibits human sperm motility. In this study, we used the 2 known inhibitors of PI3K to investigate their effect on sperm capacitation and associated protein phosphorylation events. Our data show that sperm incubated with LY294002 undergo capacitation and increased Tyr phosphorylation of specific sperm proteins in a manner similar to that promoted by the capacitation inducer fetal cord serum ultrafiltrate (FCSu), as well as double phosphorylation of the threonine (Thr)-glutamine (Glu)-Tyr motif. Under similar conditions, wortmannin did not affect these sperm functions on its own, although it did prevent the effect induced by FCSu. Consistently, wortmannin decreased the phospho (P)-Tyr content of sperm proteins and prevented the phosphorylation of their Thr-Glu-Tyr motif. We also show by means of immunoblotting and cell fractionation experiments the presence of PI3K and its downstream effector Akt (protein kinase B) at the membrane level, as well as sperm heads and flagella. Our data show that human spermatozoa contain a consensus motif usually phosphorylated by Akt and that its P-serine (Ser)/Thr content is increased by both LY294002 and FCSu, while it is decreased by wortmannin. In addition, the 2 inhibitors differently affected the intracellular calcium concentration, [Ca(2+)](i). While LY294002 increased [Ca(2+)](i), wortmannin did not affect its content and did not prevent the LY294002 effect. Thus, we propose that the LY294002-promoted increase in [Ca(2+)](i) operates independently of PI3K. In conclusion, we suggest that special care be taken when using LY294002 to investigate the role that PI3K plays in a cellular phenomenon.
Topics: Androstadienes; Calcium; Chromones; Enzyme Inhibitors; Humans; Male; Morpholines; Phosphoinositide-3 Kinase Inhibitors; Phosphoproteins; Phosphorylation; Semen; Sperm Capacitation; Sperm Motility; Spermatozoa; Wortmannin
PubMed: 15223846
DOI: 10.1002/j.1939-4640.2004.tb02828.x -
Cellular Physiology and Biochemistry :... Aug 2022In renal ischemia, the Na/K ATPase of the kidney epithelial cells translocates to intracellular compartments, resulting in altered kidney functions....
BACKGROUND/AIMS
In renal ischemia, the Na/K ATPase of the kidney epithelial cells translocates to intracellular compartments, resulting in altered kidney functions. Sphingosine-1-phosphate (S1P) was shown to play a protective role against this ischemic injury. Whether the sphingolipid targets the Na/K ATPase is a possibility that has not been explored before. This work aims at investigating the effect of S1P on renal Na/K ATPase using its analogue FTY720P and LLC-PK1 cells.
METHODS
The activity of the Na/K ATPase was assayed by measuring the amount of inorganic phosphate liberated in presence and absence of ouabain, a specific inhibitor of the enzyme while its protein expression was studied by western blot analysis.
RESULTS
FTY720P increased the activity of the ATPase in a dose and time dependent manner, with a highest effect observed at 15 minutes and a dose of 80 nM. The protein expression was also increased. The stimulation of the Na/K ATPase disappeared completely in presence of JTE-013, a specific blocker of S1PR2, as well as in presence of Y-27632, a Rho kinase inhibitor, BAPTA-AM, a Ca chelator, wortmannin, a PI3K inhibitor, carboxy-PTIO, a scavenger for nitric oxide (NO), and KT 5823, a PKG inhibitor. CYM 5520, a S1PR2 agonist mimicked the effect of FTY720P. FTY720P increased the expression of p-Akt, a direct effector of PI3K, however, this increase disappeared when Rho kinase was inhibited, revealing that Rho kinase acts upstream PI3K. Glyco-SNAP-1, a NO donor, activated the pump in both presence and absence of wortmannin, indicating that PI3K is upstream NO. Interestingly, glyco-SNAP-1 and 8-bromo-cGMP, a PKG activator, exerted no effect on the Na/K ATPase in absence of free Ca revealing that the NO mediated effect is calcium-dependent. The involvement of calcium was further confirmed by the translocation of NFAT to the nucleus. The presence of verapamil or extracellular EGTA abolished the stimulatory effect of FTY720P, indicating that the source of calcium is extracellular.
CONCLUSION
The results suggest that FTY720P activates sequentially S1PR2, Rho kinase, PI3K, leading to NO release and PKG stimulation. The latter phosphorylates calcium channels in the cell membrane, leading to calcium influx, and translocation of the ATPase units to the membrane.
Topics: Animals; Calcium; Nitric Oxide; Organophosphates; Phosphatidylinositol 3-Kinases; Sodium-Potassium-Exchanging ATPase; Sphingosine; Swine; Wortmannin; rho-Associated Kinases
PubMed: 36041048
DOI: 10.33594/000000561 -
EBioMedicine Mar 2019Skin atrophy is a major adverse effect of topical glucocorticoids. We recently reported that REDD1 (regulated in development and DNA damage 1) and FKBP51 (FK506 binding...
BACKGROUND
Skin atrophy is a major adverse effect of topical glucocorticoids. We recently reported that REDD1 (regulated in development and DNA damage 1) and FKBP51 (FK506 binding protein 5), negative regulators of mTOR/Akt signaling, are induced by glucocorticoids in mouse and human skin and are central drivers of steroid skin atrophy. Thus, we hypothesized that REDD1/FKBP51 inhibitors could protect skin against catabolic effects of glucocorticoids.
METHODS
Using drug repurposing approach, we screened LINCS library (http://lincsproject.org/LINCS/) to identify repressors of REDD1/FKBP51 expression. Candidate compounds were tested for their ability to inhibit glucocorticoid-induced REDD1/FKBP51 expression in human primary/immortalized keratinocytes and in mouse skin. Reporter gene expression, microarray, and chromatin immunoprecipitation were employed to evaluate effect of these inhibitors on the glucocorticoid receptor (GR) signaling.
FINDINGS
Bioinformatics analysis unexpectedly identified phosphoinositide-3-kinase (PI3K)/mTOR/Akt inhibitors as a pharmacological class of REDD1/FKBP51 repressors. Selected PI3K/mTOR/Akt inhibitors-Wortmannin (WM), LY294002, AZD8055, and two others indeed blocked REDD1/FKBP51expression in human keratinocytes. PI3K/mTOR/Akt inhibitors also modified global effect of glucocorticoids on trascriptome, shifting it towards therapeutically important transrepression; negatively impacted GR phosphorylation; nuclear translocation; and GR loading on REDD1/FKBP51 gene promoters. Further, topical application of LY294002 together with glucocorticoid fluocinolone acetonide (FA) protected mice against FA-induced proliferative block and skin atrophy but did not alter the anti-inflammatory activity of FA in ear edema test.
INTERPRETATION
Our results built a strong foundation for development of safer GR-targeted therapies for inflammatory skin diseases using combination of glucocorticoids with PI3K/mTOR/Akt inhibitors. FUND: Work is supported by NIH grants R01GM112945, R01AI125366, and HESI-THRIVE foundation.
Topics: Animals; Atrophy; Cell Survival; Cells, Cultured; Glucocorticoids; Humans; Keratinocytes; Mice; Mice, Inbred C57BL; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Phosphorylation; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-akt; Receptors, Glucocorticoid; Skin; TOR Serine-Threonine Kinases; Tacrolimus Binding Proteins; Transcription Factors; Transcriptome; Wortmannin
PubMed: 30737086
DOI: 10.1016/j.ebiom.2019.01.055 -
Biomedicine & Pharmacotherapy =... Jan 2024Bladder cancer cells possess unique adaptive capabilities: shaped by their environment, cells face a complex chemical mixture of metabolites and xenobiotics accompanied...
Bladder cancer cells possess unique adaptive capabilities: shaped by their environment, cells face a complex chemical mixture of metabolites and xenobiotics accompanied by physiological mechanical cues. These responses might translate into resistance to chemotherapeutical regimens and can largely rely on autophagy. Considering molecules capable of rewiring tumor plasticity, compounds of natural origin promise to offer valuable options. Fungal derived metabolites, such as bafilomycin and wortmannin are widely acknowledged as autophagy inhibitors. Here, their potential to tune bladder cancer cells´ adaptability to chemical and physical stimuli was assessed. Additionally, dietary occurring mycotoxins were also investigated, namely deoxynivalenol (DON, 0.1-10 µM) and fusaric acid (FA, 0.1-1 mM). Endowing a Janus' face behavior, DON and FA are on the one side described as toxins with detrimental health effects. Concomitantly, they are also explored experimentally for selective pharmacological applications including anticancer activities. In non-cytotoxic concentrations, bafilomycin (BAFI, 1-10 nM) and wortmannin (WORT, 1 µM) modified cell morphology and reduced cancer cell migration. Application of shear stress and inhibition of mechano-gated PIEZO channels reduced cellular sensitivity to BAFI treatment (1 nM). Similarly, for FA (0.5 mM) PIEZO1 expression and inhibition largely aligned with the modulatory potential on cancer cells motility. Additionally, this study highlighted that the activity profile of compounds with similar cytotoxic potential (e.g. co-incubation DON with BAFI or FA with WORT) can diverge substantially in the regulation of cell mechanotransduction. Considering the interdependence between tumor progression and response to mechanical cues, these data promise to provide a novel viewpoint for the study of chemoresistance and associated pathways.
Topics: Humans; Mechanotransduction, Cellular; Wortmannin; Autophagy; Antineoplastic Agents; Urinary Bladder Neoplasms; Ion Channels
PubMed: 38042111
DOI: 10.1016/j.biopha.2023.115942 -
Cancer Science Sep 2008Phosphatidylinositol 3-kinases (PI3K) are a group of lipid kinases that phosphorylate phosphoinositides at the 3-hydroxyl group of the inositol ring to generate... (Review)
Review
Phosphatidylinositol 3-kinases (PI3K) are a group of lipid kinases that phosphorylate phosphoinositides at the 3-hydroxyl group of the inositol ring to generate phosphatidylinositol 3,4,5-trisphosphate, a second messenger with key roles in fundamental cellular responses such as cell proliferation and metabolism. Frequent mutations found in or amplification of the PIK3CA gene and loss of phosphatase and tensin homolog deleted on chromosome 10 function in human tumors suggest that PI3K is a potential target for cancer therapy. During the last 5 years, several specific PI3K inhibitors were developed that were directed against various diseases. Some of them revealed potent anticancer efficacy and are now undergoing clinical trials. Some PI3K inhibitors showed antiangiogenic effects. Combined use of PI3K inhibitors with other chemotherapeutic agents or with radiotherapy produced synergistic therapeutic efficacies in treating cancer and showed reduced side effects. The rapid progress made in developing novel PI3K inhibitors in recent years promises bright prospects for finding a PI3K-targeted anticancer drug in the near future.
Topics: Androstadienes; Angiogenesis Inhibitors; Antineoplastic Agents; Cell Proliferation; Chromones; Combined Modality Therapy; Humans; Morpholines; Neoplasms; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Protein Isoforms; Protein Kinase Inhibitors; Wortmannin
PubMed: 18616528
DOI: 10.1111/j.1349-7006.2008.00891.x -
British Journal of Cancer Nov 1999Wortmannin is a potent inhibitor of phosphatidylinositol (PI) 3-kinase and PI 3-kinase-related proteins (e.g. ATM), but it does not inhibit the activity of purified...
Effects of the protein kinase inhibitors wortmannin and KN62 on cellular radiosensitivity and radiation-activated S phase and G1/S checkpoints in normal human fibroblasts.
Wortmannin is a potent inhibitor of phosphatidylinositol (PI) 3-kinase and PI 3-kinase-related proteins (e.g. ATM), but it does not inhibit the activity of purified calmodulin-dependent protein kinase II (CaMKII). In the present study, we compared the effects of wortmannin and the CaMKII inhibitor KN62 on the response of normal human dermal fibroblast cultures to gamma radiation. We demonstrate that wortmannin confers a phenotype on normal fibroblasts remarkably similar to that characteristic of cells homozygous for the ATM mutation. Thus wortmannin-treated normal fibroblasts exhibit increased sensitivity to radiation-induced cell killing, lack of temporary block in transition from G1 to S phase following irradiation (i.e. impaired G1/S checkpoint), and radioresistant DNA synthesis (i.e. impaired S phase checkpoint). Wortmannin-treated cultures display a diminished capacity for radiation-induced up-regulation of p53 protein and expression of p21WAF1, a p53-regulated gene involved in cell cycle arrest at the G1/S border; the treated cultures also exhibit decreased capacity for enhancement of CaMKII activity post-irradiation, known to be necessary for triggering the S phase checkpoint. We further demonstrate that KN62 confers a radioresistant DNA synthesis phenotype on normal fibroblasts and moderately potentiates their sensitivity to killing by gamma rays, without modulating G1/S checkpoint, p53 up-regulation and p21WAF1 expression following radiation exposure. We conclude that CaMKII is involved in the radiation responsive signalling pathway mediating S phase checkpoint but not in the p53-dependent pathway controlling G1/S checkpoint, and that a wortmannin-sensitive kinase functions upstream in both pathways.
Topics: Androstadienes; Calcium-Calmodulin-Dependent Protein Kinases; Cyclin-Dependent Kinase Inhibitor p21; Cyclins; Fibroblasts; Humans; Protein Kinase Inhibitors; Radiation, Ionizing; Radiation-Sensitizing Agents; S Phase; Tumor Cells, Cultured; Tumor Suppressor Protein p53; Wortmannin
PubMed: 10576651
DOI: 10.1038/sj.bjc.6690793