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Particle and Fibre Toxicology Jan 2024As the demand and application of engineered nanomaterials have increased, their potential toxicity to the central nervous system has drawn increasing attention....
BACKGROUND
As the demand and application of engineered nanomaterials have increased, their potential toxicity to the central nervous system has drawn increasing attention. Tunneling nanotubes (TNTs) are novel cell-cell communication that plays a crucial role in pathology and physiology. However, the relationship between TNTs and nanomaterials neurotoxicity remains unclear. Here, three types of commonly used engineered nanomaterials, namely cobalt nanoparticles (CoNPs), titanium dioxide nanoparticles (TiONPs), and multi-walled carbon nanotubes (MWCNTs), were selected to address this limitation.
RESULTS
After the complete characterization of the nanomaterials, the induction of TNTs formation with all of the nanomaterials was observed using high-content screening system and confocal microscopy in both primary astrocytes and U251 cells. It was further revealed that TNT formation protected against nanomaterial-induced neurotoxicity due to cell apoptosis and disrupted ATP production. We then determined the mechanism underlying the protective role of TNTs. Since oxidative stress is a common mechanism in nanotoxicity, we first observed a significant increase in total and mitochondrial reactive oxygen species (namely ROS, mtROS), causing mitochondrial damage. Moreover, pretreatment of U251 cells with either the ROS scavenger N-acetylcysteine or the mtROS scavenger mitoquinone attenuated nanomaterial-induced neurotoxicity and TNTs generation, suggesting a central role of ROS in nanomaterials-induced TNTs formation. Furthermore, a vigorous downstream pathway of ROS, the PI3K/AKT/mTOR pathway, was found to be actively involved in nanomaterials-promoted TNTs development, which was abolished by LY294002, Perifosine and Rapamycin, inhibitors of PI3K, AKT, and mTOR, respectively. Finally, western blot analysis demonstrated that ROS and mtROS scavengers suppressed the PI3K/AKT/mTOR pathway, which abrogated TNTs formation.
CONCLUSION
Despite their biophysical properties, various types of nanomaterials promote TNTs formation and mitochondrial transfer, preventing cell apoptosis and disrupting ATP production induced by nanomaterials. ROS/mtROS and the activation of the downstream PI3K/AKT/mTOR pathway are common mechanisms to regulate TNTs formation and mitochondrial transfer. Our study reveals that engineered nanomaterials share the same molecular mechanism of TNTs formation and intercellular mitochondrial transfer, and the proposed adverse outcome pathway contributes to a better understanding of the intercellular protection mechanism against nanomaterials-induced neurotoxicity.
Topics: Proto-Oncogene Proteins c-akt; Reactive Oxygen Species; Phosphatidylinositol 3-Kinases; Nanotubes, Carbon; TOR Serine-Threonine Kinases; Neuroglia; Adenosine Triphosphate; Apoptosis; Cell Membrane Structures; Nanotubes
PubMed: 38225661
DOI: 10.1186/s12989-024-00562-0 -
Annals of Clinical and Translational... Apr 2020Malignant glioma (MG) is the most deadly primary brain cancer. Signaling though the PI3K/AKT/mTOR axis is activated in most MGs and therefore a potential therapeutic...
PURPOSE
Malignant glioma (MG) is the most deadly primary brain cancer. Signaling though the PI3K/AKT/mTOR axis is activated in most MGs and therefore a potential therapeutic target. The mTOR inhibitor temsirolimus and the AKT inhibitor perifosine are each well-tolerated as single agents but with limited activity reclinical data demonstrate synergistic anti-tumor effects from combined treatment. Therefore, we initiated a phase I trial of combined therapy in recurrent MGs to determine safety and a recommended phase II dose.
METHODS
Adults with recurrent MG, Karnofsky Performance Status ≥ 60 were enrolled, with no limit on the number of prior therapies. Temsirolimus dose was escalated using standard 3 + 3 design from 15 mg to 170 mg administered once weekly. Perifosine was fixed as a 600 mg load on day 1 followed by 100 mg nightly (single agent MTD) until dose level 7 when the load increased to 900 mg.
RESULTS
We treated 35 patients with with glioblastoma (17) or other MGs (18; including nine anaplastic astrocytoma, nine anaplastic oligodendroglioma, one anaplastic oligoastrocytoma, and two low grade astrocytomas with radiographic transformation to MG). We observed five dose-limiting toxicities (DLTs): one at dose level 3 (50mg temsirolimus), then two at dose level 7 expansion (170 mg temsirolimus), and then two more at dose level 6 expansion (170 mg temsirolimus). DLTs included thrombocytopenia (n = 3), intracerebral hemorrhage (n = 1) and lung infection (n = 1).
CONCLUSION
Combining the mTOR inhibitor temsirolimus dosed at 115 mg weekly and the AKT inhibitor perifosine dosed at 100 mg daily (following 600 mg load) is tolerable in heavily pretreated adults with recurrent MGs.
Topics: Adult; Aged; Antineoplastic Agents; Brain Neoplasms; Drug Therapy, Combination; Female; Glioblastoma; Humans; Male; Middle Aged; Neoplasm Recurrence, Local; Phosphorylcholine; Prospective Studies; Proto-Oncogene Proteins c-akt; Sirolimus; TOR Serine-Threonine Kinases; Young Adult
PubMed: 32293798
DOI: 10.1002/acn3.51009 -
Computational and Mathematical Methods... 2021To research the molecular mechanism of ghrelin in apoptosis, migratory, and invasion of gastric cancer (GC) cells.
AIM
To research the molecular mechanism of ghrelin in apoptosis, migratory, and invasion of gastric cancer (GC) cells.
METHODS
After GC AGS cells were handled with ghrelin (10 M), cyclooxygenase-2 inhibitor NS398 (100 M), and Akt inhibitor perifosine (10uM), the rates of apoptosis were detected by TUNEL assay and flow cytometry assay. We assessed the expressions of PI3K, p-Akt, and COX-2 proteins by making use of Western blot analysis. The cell migratory and invasion were detected by using wound-healing and transwell analysis.
RESULTS
The migratory and invasion were increased in ghrelin-treated cells, while the rates of apoptosis were decreased. GC AGS cells treated with ghrelin showed an increase in protein expression of p-Akt, PI3K, and COX-2. After cells were treated with Akt inhibitor perifosine, the protein expression of p-Akt, PI3K, and COX-2 and the cell migratory, invasion, and apoptosis were partly recovered. After cells were treated with cyclooxygenase-2 inhibitor NS398, the protein expression of COX-2 and the cell migratory and invasion were decreased, while the rates of apoptosis were increased.
CONCLUSION
Ghrelin regulates cell migration, invasion, and apoptosis in GC cells through targeting PI3K/Akt/COX-2. Ghrelin increases the expression of COX-2 in GC cells by targeting PI3K/Akt. Ghrelin is suggested to be one of the molecular targets in GC.
Topics: Apoptosis; Cell Line, Tumor; Cell Movement; Computational Biology; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Disease Progression; Ghrelin; Humans; Neoplasm Invasiveness; Nitrobenzenes; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins c-akt; Signal Transduction; Stomach Neoplasms; Sulfonamides
PubMed: 34122616
DOI: 10.1155/2021/5576808 -
Biology Nov 2023Alkylphospholipids (APLs) have been studied as anticancer drugs that interfere with biological membranes without targeting DNA. Although their mechanism of action is not...
Alkylphospholipids (APLs) have been studied as anticancer drugs that interfere with biological membranes without targeting DNA. Although their mechanism of action is not fully elucidated yet, it is known that they disrupt the intracellular trafficking of cholesterol and its metabolism. Here, we analyzed whether APLs could also interfere with mitochondrial function. For this purpose, we used HT29 colorectal cancer cells, derived from a primary tumor, and SW620 colorectal cancer cells, derived from a metastasis site. After treatment with the APLs miltefosine and perifosine, we analyzed various mitochondrial parameters, including mitochondrial mass, cardiolipin content, mitochondrial membrane potential, HO production, the levels of oxidative phosphorylation (OXPHOS) complexes, metabolic enzymes activity, the oxygen consumption rate, and the levels of apoptosis and autophagy markers. APLs, especially perifosine, increased mitochondrial mass while OXPHOS complexes levels were decreased without affecting the total oxygen consumption rate. Additionally, we observed an increase in pyruvate dehydrogenase (PDH) and isocitrate dehydrogenase (IDH) levels and a decrease in lactate dehydrogenase (LDH) activity, suggesting a metabolic rewiring induced by perifosine. These alterations led to higher mitochondrial membrane potential, which was potentiated by decreased uncoupling protein 2 (UCP2) levels and increased reactive oxygen species (ROS) production. Consequently, perifosine induced an imbalance in mitochondrial function, resulting in higher ROS production that ultimately impacted cellular viability.
PubMed: 38132283
DOI: 10.3390/biology12121457 -
Frontiers in Oncology 2021Metastatic brain tumors are regarded as the most advanced stage of certain types of cancer; however, chemotherapy has played a limited role in the treatment of brain...
Metastatic brain tumors are regarded as the most advanced stage of certain types of cancer; however, chemotherapy has played a limited role in the treatment of brain metastases. Here, we established murine models of brain metastasis using cell lines derived from human brain metastatic tumors, and aimed to explore the antitumor efficacy of perifosine, an orally active allosteric Akt inhibitor. We evaluated the effectiveness of perifosine by using it as a single agent in ectopic and orthotopic models created by injecting the DU 145 and NCI-H1915 cell lines into mice. Initially, the injected cells formed distant multifocal lesions in the brains of NCI-H1915 mice, making surgical resection impractical in clinical settings. We determined that perifosine could distribute into the brain and remain localized in that region for a long period. Perifosine significantly prolonged the survival of DU 145 and NCI-H1915 orthotopic brain tumor mice; additionally, complete tumor regression was observed in the NCI-H1915 model. Perifosine also elicited much stronger antitumor responses against subcutaneous NCI-H1915 growth; a similar trend of sensitivity to perifosine was also observed in the orthotopic models. Moreover, the degree of suppression of NCI-H1915 tumor growth was associated with long-term exposure to a high level of perifosine at the tumor site and the resultant blockage of the PI3K/Akt signaling pathway, a decrease in tumor cell proliferation, and increased apoptosis. The results presented here provide a promising approach for the future treatment of patients with metastatic brain cancers and emphasize the importance of enriching a patient population that has a higher probability of responding to perifosine.
PubMed: 34804943
DOI: 10.3389/fonc.2021.754365 -
European Review For Medical and... Apr 2018It is to study the stimulation and possible active mechanism of miRNA-21 on AGS proliferation of gastric cancer.
OBJECTIVE
It is to study the stimulation and possible active mechanism of miRNA-21 on AGS proliferation of gastric cancer.
MATERIALS AND METHODS
AGS gastric cancer cells were cultivated in vitro and then divided into the blank control group, the PGE2 (prostaglandin E2) group, the anti-miRNA-21 group and the PGE2 + anti-miRNA-21 group and the MTT and the flow cytometry methods were adopted to test the effect of PGE2 or/and anti-miRNA-21 intervention on AGS cell proliferation and apoptosis and the differences to miRNA-21 expression. In addition, the cells were also divided into the blank control group, the PGE2 group, the PGE2 + Perifosine group, the PGE2 + anti-miRNA-21 group and the PGE2 + anti-miRNA-21 + Perifosine group and the MTT and flow cytometry methods were adopted to test the effect of Perifosine intervention on AGS cell proliferation and apoptosis and on PTEN and p-AktmRNA and protein expressions.
RESULTS
Compared with the control group, AGS cell proliferation activity increased significantly, the apoptosis rate decreased and the miRNA-21tmRNA and protein expression increased in the PGE2 group (p < 0.05); compared with the PGE2 group, the AGS cell proliferation rate decreased, the apoptosis rate increased and the miRNA-21mRNA and protein expressions decreased (p < 0.05) in the anti-miRNA-21 group and the PGE2 + anti-miRNA-21 group. In addition, after intervention of Perifosine, the AGS cell proliferation rate decreased, the apoptosis rate increased, the PTEN mRNA and protein expressions increased and the pAktmRNA and protein expressions decreased (p < 0.05).
CONCLUSIONS
miRNA-21 may promote the growth of gastric cancer cells by adjusting and controlling PTEN/Akt signal passage mediated PEG2.
Topics: Apoptosis; Cell Line, Tumor; Cell Proliferation; Dinoprostone; Humans; MicroRNAs; PTEN Phosphohydrolase; Stomach Neoplasms
PubMed: 29687845
DOI: 10.26355/eurrev_201804_14717 -
Translational Cancer Research Dec 2018Perifosine, is a third generation alkylphospholipid analog which has promising anti-tumor efficacy in clinical trials of refractory/recurrent neuroblastoma (NB)....
BACKGROUND
Perifosine, is a third generation alkylphospholipid analog which has promising anti-tumor efficacy in clinical trials of refractory/recurrent neuroblastoma (NB). However, perifosine's mechanism of action remains unclear. Previously, we have shown that perifosine changes global proteome and acetylome profiles in NB.
METHODS
To obtain a more comprehensive understanding of the perifosine mechanism, we performed a quantitative assessment of the lysine ubiquitylome in SK-N-AS NB cells using SILAC labeling, affinity enrichment and high-resolution liquid chromatography combined with mass spectrometry analysis. To analyse the data of ubiquitylome, we performed enrichment analysis with gene ontology (GO), the Encyclopedia of Genes and Genomes (KEGG) pathway, ubiquitylated lysine motif, protein complex and protein domain. Protein-protein interaction was conducted to explore the crosstalk between ubiquitylome and previous global proteome/acetylome. Co-immunoprecipitation and western blotting were used to validate the results of the ubiquitylome analysis.
RESULTS
Altogether, 3,935 sites and 1,658 proteins were quantified. These quantified ubiquitylated proteins participated in various cellular processes such as binding, catalytic activity, biological regulation, metabolic process and signaling pathways involving non-homologous end-joining, steroid biosynthesis and Ras signaling pathway. Ubiquitylome and proteome presented negative connection. We identified 607 sites which were modified with both ubiquitination and acetylation. We selected 14 proteins carrying differentially quantified lysine ubiquitination and acetylation sites at the threshold of 1.5 folds as potential targets. These proteins were enriched in activities associated with ribosome, cell cycle and metabolism.
CONCLUSIONS
Our study extends our understanding of the spectrum of novel targets that are differentially ubiquitinated after perifosine treatment of NB tumor cells.
PubMed: 30761266
DOI: 10.21037/tcr.2018.11.30 -
EJHaem Jul 2020Perifosine, an investigational, oral, synthetic alkylphospholipid, inhibits signal transduction pathways of relevance in multiple myeloma (MM) including PI3K/Akt....
Randomized, placebo-controlled, phase 3 study of perifosine combined with bortezomib and dexamethasone in patients with relapsed, refractory multiple myeloma previously treated with bortezomib.
Perifosine, an investigational, oral, synthetic alkylphospholipid, inhibits signal transduction pathways of relevance in multiple myeloma (MM) including PI3K/Akt. Perifosine demonstrated anti-MM activity in preclinical studies and encouraging early-phase clinical activity in combination with bortezomib. A randomized, double-blind, placebo-controlled phase 3 study was conducted to evaluate addition of perifosine to bortezomib-dexamethasone in MM patients with one to four prior therapies who had relapsed following previous bortezomib-based therapy. The primary endpoint was progression-free survival (PFS). The study was discontinued at planned interim analysis, with 135 patients enrolled. Median PFS was 22.7 weeks (95% confidence interval 16·0-45·4) in the perifosine arm and 39.0 weeks (18.3-50.1) in the placebo arm (hazard ratio 1.269 [0.817-1.969]; = .287); overall response rates were 20% and 27%, respectively. Conversely, median overall survival (OS) was 141.9 weeks and 83.3 weeks (hazard ratio 0.734 [0.380-1.419]; = .356). Overall, 61% and 55% of patients in the perifosine and placebo arms reported grade 3/4 adverse events, including thrombocytopenia (26% vs 14%), anemia (7% vs 8%), hyponatremia (6% vs 8%), and pneumonia (9% vs 3%). These findings demonstrate no PFS benefit from the addition of perifosine to bortezomib-dexamethasone in this study of relapsed/refractory MM, but comparable safety and OS.
PubMed: 35847734
DOI: 10.1002/jha2.4 -
Neuroscience Bulletin Apr 2018Accumulating data have revealed that abnormal activity of the mTOR (mammalian target of rapamycin) pathway plays an important role in epileptogenesis triggered by...
Accumulating data have revealed that abnormal activity of the mTOR (mammalian target of rapamycin) pathway plays an important role in epileptogenesis triggered by various factors. We previously reported that pretreatment with perifosine, an inhibitor of Akt (also called protein kinase B), abolishes the rapamycin-induced paradoxical increase of S6 phosphorylation in a rat model induced by kainic acid (KA). Since Akt is an upstream target in the mTOR signaling pathway, we set out to determine whether perifosine has a preventive effect on epileptogenesis. Here, we explored the effect of perifosine on the model of temporal epilepsy induced by KA in rats and found that pretreatment with perifosine had no effect on the severity or duration of the KA-induced status epilepticus. However, perifosine almost completely inhibited the activation of p-Akt and p-S6 both acutely and chronically following the KA-induced status epilepticus. Perifosine pretreatment suppressed the KA-induced neuronal death and mossy fiber sprouting. The frequency of spontaneous seizures was markedly decreased in rats pretreated with perifosine. Accordingly, rats pretreated with perifosine showed mild impairment in cognitive functions. Collectively, this study provides novel evidence in a KA seizure model that perifosine may be a potential drug for use in anti-epileptogenic therapy.
Topics: Animals; Anticonvulsants; Brain; Convulsants; Disease Models, Animal; Epilepsy, Temporal Lobe; Kainic Acid; Male; Neurons; Phosphorylcholine; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-akt; Rats; Rats, Sprague-Dawley; Status Epilepticus
PubMed: 28786074
DOI: 10.1007/s12264-017-0165-7 -
Cell Death & Disease May 2019Triple-negative breast cancer (TNBC) treatment remains a great challenge for clinical practice and novel therapeutic strategies are urgently needed. UCHL3 is a...
Triple-negative breast cancer (TNBC) treatment remains a great challenge for clinical practice and novel therapeutic strategies are urgently needed. UCHL3 is a deubiquitinase that is overexpressed in TNBC and correlates with poor prognosis. UCHL3 deubiquitinates RAD51 thereby promoting the recruitment of RAD51 to DNA damage sites and augmenting DNA repair. Therefore, UCHL3 overexpression can render cancer cells resistant to DNA damage inducing chemo and radiotherapy, and targeting UCHL3 can sensitize TNBC to radiation and chemotherapy. However, small molecule inhibitors of UCHL3 are yet to be identified. Here we report that perifosine, a previously reported Akt inhibitor, can inhibit UCHL3 in vitro and in vivo. We found low dose (50 nM) perifosine inhibited UCHL3 deubiquitination activity without affecting Akt activity. Furthermore, perifosine enhanced Olaparib-induced growth inhibition in TNBC cells. Mechanistically, perifosine induced RAD51 ubiquitination and blocked the RAD51-BRCA2 interaction, which in turn decreased ionizing radiation-induced foci (IRIF) of Rad51 and, thereby, homologous recombination (HR)-mediated DNA double strand break repair. In addition, combination of perifosine and Olaparib showed synergistic antitumor activity in vivo in TNBC xenograft model. Thus, our present study provides a novel therapeutic approach to optimize PARP inhibitor treatment efficiency.
Topics: Animals; Antineoplastic Agents; Apoptosis; BRCA2 Protein; Cell Line, Tumor; Female; Humans; Mice; Mice, Nude; Phosphorylcholine; Phthalazines; Piperazines; Poly(ADP-ribose) Polymerase Inhibitors; Rad51 Recombinase; Radiation, Ionizing; Recombinational DNA Repair; Transplantation, Heterologous; Triple Negative Breast Neoplasms; Ubiquitin Thiolesterase; Ubiquitination; RNA, Guide, CRISPR-Cas Systems
PubMed: 31113933
DOI: 10.1038/s41419-019-1628-8