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Apoptosis : An International Journal on... Aug 2017Bevacizumab (BVZ) as an antiangiogenesis therapy leads to a transient therapeutic efficacy in high-grade glioma. However, the proapoptotic potential of BVZ has not been...
Bevacizumab (BVZ) as an antiangiogenesis therapy leads to a transient therapeutic efficacy in high-grade glioma. However, the proapoptotic potential of BVZ has not been well elucidated, yet. There is also a tumor resistance to BVZ that is linked to post-treatment metalloproteinases and AKT activities. Herein, the association between therapeutic efficacy and putative proapoptotic activity of low-dose BVZ either alone or in combination with a specific inhibitor of AKT called perifosine (PRF), in a glioma model was investigated. BALB/c mice bearing C6 glioma tumor were treated with BVZ and PRF either alone or combined for 13 days (n = 11/group). At the end of treatments, apoptosis, proliferation and vascular density, in the xenografts (3/group) were detected by TUNEL staining, Ki67 and CD31 markers, respectively. Relative levels of cleaved-caspase3, phospho-AKT (Ser473) and matrix metalloproteinase2 (MMP2) were measured using western blotting. PRF and BVZ separately slowed down tumor growth along with the cell apoptosis induction associated with a profound increase in caspase3 activity through an AKT inhibition-related pathway for PRF but not BVZ. Unlike PRF, BVZ significantly increased the intratumor MMP2 and phospho-AKT (Ser473) levels coupled with the slight antiproliferative and significant antivascular effects. Co-administration of PRF and BVZ versus monotherapies potentiated the proapoptotic effects and reversed the BVZ-induced upregulation of phospho-AKT (Ser473) and MMP2 levels in C6 xenografts, leading to the optimal antiproliferative activity and tumor growth regression and longer survival. In conclusion, BVZ plus PRF renders a paramount proapoptotic effect, leading to a major therapeutic efficacy and might be a new substitute for GBM therapy in the clinic.
Topics: Animals; Apoptosis; Bevacizumab; Caspase 3; Cell Line, Tumor; Gene Expression Regulation, Neoplastic; Glioblastoma; Humans; Matrix Metalloproteinase 2; Mice; Phosphatidylinositol 3-Kinases; Phosphorylcholine; Proto-Oncogene Proteins c-akt; Xenograft Model Antitumor Assays
PubMed: 28616662
DOI: 10.1007/s10495-017-1382-2 -
Frontiers in Oncology 2020Colorectal cancer (CRC) is a disease with constantly increasing incidence and high mortality. The treatment efficacy could be curtailed by drug resistance resulting from...
Colorectal cancer (CRC) is a disease with constantly increasing incidence and high mortality. The treatment efficacy could be curtailed by drug resistance resulting from poor drug penetration into tumor tissue and the tumor-specific microenvironment, such as hypoxia and acidosis. Furthermore, CRC tumors can be exposed to different pH depending on the position in the intestinal tract. CRC tumors often share upregulation of the Akt signaling pathway. In this study, we investigated the role of external pH in control of cytotoxicity of perifosine, the Akt signaling pathway inhibitor, to CRC cells using 2D and 3D tumor models. In 3D settings, we employed an innovative strategy for simultaneous detection of spatial drug distribution and biological markers of proliferation/apoptosis using a combination of mass spectrometry imaging and immunohistochemistry. In 3D conditions, low and heterogeneous penetration of perifosine into the inner parts of the spheroids was observed. The depth of penetration depended on the treatment duration but not on the external pH. However, pH alteration in the tumor microenvironment affected the distribution of proliferation- and apoptosis-specific markers in the perifosine-treated spheroid. Accurate co-registration of perifosine distribution and biological response in the same spheroid section revealed dynamic changes in apoptotic and proliferative markers occurring not only in the perifosine-exposed cells, but also in the perifosine-free regions. Cytotoxicity of perifosine to both 2D and 3D cultures decreased in an acidic environment below pH 6.7. External pH affects cytotoxicity of the other Akt inhibitor, MK-2206, in a similar way. Our innovative approach for accurate determination of drug efficiency in 3D tumor tissue revealed that cytotoxicity of Akt inhibitors to CRC cells is strongly dependent on pH of the tumor microenvironment. Therefore, the effect of pH should be considered during the design and pre-clinical/clinical testing of the Akt-targeted cancer therapy.
PubMed: 33344237
DOI: 10.3389/fonc.2020.581365 -
Molecular Cancer Therapeutics Nov 2003Perifosine is a novel p.o. bioavailable alkylphospholipid. Perifosine has displayed significant antiproliferative activity in vitro and in vivo in several human tumor...
Perifosine is a novel p.o. bioavailable alkylphospholipid. Perifosine has displayed significant antiproliferative activity in vitro and in vivo in several human tumor model systems and has recently entered phase I clinical trials. Recent studies have identified that perifosine could cause cell cycle arrest with induction of p21(WAF1/CIP1) in a p53-independent fashion; however, the basis for that effect is not known. Structurally, perifosine resembles naturally occurring phospholipids. Therefore, we hypothesized that perifosine might perturb pathways related to phospholipids modulated by growth factor action. We demonstrate here that perifosine causes dose-dependent inhibition of protein kinase B/Akt phosphorylation and thus activation at concentrations causing growth inhibition of PC-3 prostate carcinoma cells. Only the myristoylated form of Akt (MYR-Akt), which bypasses the requirement for pleckstrin homology (PH) domain-mediated membrane recruitment, abrogated perifosine-mediated decrease of Akt phosphorylation and cell growth inhibition by perifosine. We demonstrate further that perifosine decreases the plasma membrane localization of Akt, and this is substantially relieved by MYR-Akt along with relief of downstream drug effect on induction of p21(WAF1/CIP1). Perifosine does not directly affect phosphoinositide 3-kinase (PI3K), phosphoinositide-dependent kinase 1, or Akt activity at concentrations inhibiting Akt phosphorylation and membrane localization. Our results demonstrate that Akt is an important cellular target of perifosine action. In addition, these studies show that the membrane translocation of certain PH domain-containing molecules can be greatly perturbed by the alkylphospholipid class of drugs and imply further that the PI3K/Akt pathway contributes to regulation of p21(WAF1/CIP1) expression.
Topics: Cell Division; Cell Line, Tumor; Cyclin-Dependent Kinase Inhibitor p21; Cyclins; Enzyme Activation; Enzyme Inhibitors; Gene Expression Regulation, Neoplastic; Growth Substances; Humans; Male; Molecular Structure; Phosphatidylinositol 3-Kinases; Phosphorylation; Phosphorylcholine; Prostatic Neoplasms; Protein Serine-Threonine Kinases; Protein Transport; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-akt; Signal Transduction; Up-Regulation
PubMed: 14617782
DOI: No ID Found -
Leukemia & Lymphoma May 2014Abstract Because of the importance of the phosphoinositide 3-kinase (PI3K)/AKT pathway in chronic lymphocytic leukemia (CLL), we evaluated in vitro cytotoxicity induced...
Abstract Because of the importance of the phosphoinositide 3-kinase (PI3K)/AKT pathway in chronic lymphocytic leukemia (CLL), we evaluated in vitro cytotoxicity induced by perifosine, an AKT inhibitor, in CLL lymphocytes and found that the mean 50% effective dose (ED50) was 313 nM. We then performed a phase II trial of perifosine in patients with relapsed/refractory CLL to assess response, outcomes, toxicity and ex vivo correlative measures. After 3 months of treatment, six of eight patients showed stable disease, one achieved a partial response and one had progressive disease. Median event-free survival and overall survival in all patients treated were 3.9 and 9.7 months. Adverse events included hematologic, infectious/fever, pain, gastrointestinal and constitutional toxicities. Unexpectedly, AKT phosphorylation in CLL lymphocytes from treated patients was not correlated with response. Additionally, perifosine did not inhibit AKT phosphorylation in cultured CLL lymphocytes. Perifosine is cytotoxic to CLL cells in vitro, and largely induces stabilized disease in vivo, with an AKT-independent mechanism.
Topics: Aged; Aged, 80 and over; Antineoplastic Agents; Cell Survival; Dose-Response Relationship, Drug; Female; Humans; Leukemia, Lymphocytic, Chronic, B-Cell; Male; Middle Aged; Neoplasm Staging; Phosphorylation; Phosphorylcholine; Proto-Oncogene Proteins c-akt; Signal Transduction; Treatment Outcome
PubMed: 23863122
DOI: 10.3109/10428194.2013.824080 -
International Journal of Cancer Dec 2012Our study shows that coadministration of curcumin and an orally bioactive alkylphospholipid perifosine results in a significant increase in colorectal cancer cell...
Our study shows that coadministration of curcumin and an orally bioactive alkylphospholipid perifosine results in a significant increase in colorectal cancer cell apoptosis and a marked inhibition of cell growth both in vitro and in vivo. This novel combinatorial regimen leads to changes of multiple cell signaling pathways including inactivation of Akt and nuclear factor-κB as well as activation of c-Jun N-terminal kinases and endoplasmic reticulum stress. Further, perifosine and curcumin synergistically increase intracellular level of reactive oxygen species and ceramide, and downregulate the expression of cyclin D1 and Bcl-2 in colorectal cancer cells. These changes at molecular level together account for the cancer cell apoptosis and growth inhibition. We conclude that perifosine sensitizes colorectal cancer cells to curcumin by modulating multiple signaling pathways. Adding perifosine with curcumin may represent an effective therapy regimen against colorectal cancers, and possible other aggressive tumors.
Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Caco-2 Cells; Cell Death; Cell Line, Tumor; Cell Proliferation; Ceramides; Colorectal Neoplasms; Curcumin; Cyclin D1; Down-Regulation; Drug Synergism; Endoplasmic Reticulum; Female; HCT116 Cells; HT29 Cells; Humans; I-kappa B Proteins; JNK Mitogen-Activated Protein Kinases; Mechanistic Target of Rapamycin Complex 1; Mice; Mice, SCID; Multiprotein Complexes; NF-KappaB Inhibitor alpha; NF-kappa B; Phosphorylation; Phosphorylcholine; Proteins; Proto-Oncogene Proteins c-akt; Proto-Oncogene Proteins c-bcl-2; Reactive Oxygen Species; Signal Transduction; TOR Serine-Threonine Kinases; Xenograft Model Antitumor Assays
PubMed: 22438101
DOI: 10.1002/ijc.27548 -
Molecular and Cellular Biochemistry Sep 2012Targeting angiogenesis is considered an effective strategy for treating the expansion and metastasis of tumors. The aim of this study is to assess the effects of...
Targeting angiogenesis is considered an effective strategy for treating the expansion and metastasis of tumors. The aim of this study is to assess the effects of perifosine, an inhibitor of Akt, on cell proliferation, apoptosis, angiogenesis, and VEGF-induced cell migration in cultured human umbilical vein endothelial cells (HUVECs) in vitro. MTT and cell cycle analysis results indicated that perifosine inhibited the growth of HUVECs in a dose-dependent manner, arrested cell cycle progression at the G(2) phase with regulation the expression of p21 and cyclinB1. Apoptosis induced by the higher concentrations of perifosine in HUVECs was also observed. In addition, tube formation of HUVECs and VEGF-induced cell migration were markedly inhibited by perifosine. Western blotting analysis of cell signaling molecules indicated that perifosine inhibited ERK and p38 phosphorylation in HUVECs. These results suggest that perifosine exerts anti-angiogenic activity in HUVECs and is a promising agent for treatment of angiogenesis related-diseases.
Topics: Antineoplastic Agents; Cell Line; Cell Movement; Cyclin B1; G2 Phase; Human Umbilical Vein Endothelial Cells; Humans; Neovascularization, Pathologic; Phosphorylation; Phosphorylcholine; Proto-Oncogene Proteins c-akt; Vascular Endothelial Growth Factor A; p38 Mitogen-Activated Protein Kinases
PubMed: 21769450
DOI: 10.1007/s11010-011-0986-z -
Investigational New Drugs Apr 2011The effect of the single-chain alkylphospholipid perifosine was analyzed in p53(wild-type) (SKW6.4, OCI and MOLM), p53(mutated) (BJAB, MAVER) and p53(null) (HL-60)...
The effect of the single-chain alkylphospholipid perifosine was analyzed in p53(wild-type) (SKW6.4, OCI and MOLM), p53(mutated) (BJAB, MAVER) and p53(null) (HL-60) leukemic cell lines. Perifosine promoted cytotoxicity with a combination of apoptosis induction in all cell lines and cell cycle block at the G(2)M checkpoint, which was selectively observed in p53(mutated) BJAB and MAVER cell lines. At the molecular level, perifosine induced hypophosphorylation of retinoblastoma protein and the degradation of E2F1 protein in p53(mutated) but not in p53(wild-type) cells. These data indicate that perifosine potentially represents an innovative therapeutic approach for p53(mutated) hematological malignancies.
Topics: Apoptosis; Cell Cycle; Cell Line, Tumor; Cell Survival; Drug Screening Assays, Antitumor; E2F1 Transcription Factor; Humans; Leukemia; Mutation; Phosphorylcholine; Retinoblastoma Protein; Tumor Suppressor Protein p53
PubMed: 20130960
DOI: 10.1007/s10637-009-9370-1 -
Endocrine-related Cancer Jun 2012The majority of neuroendocrine tumors (NETs) of the gastroenteropancreatic system show aberrant Akt activity. Several inhibitors of the phosphoinositide 3-kinase...
The majority of neuroendocrine tumors (NETs) of the gastroenteropancreatic system show aberrant Akt activity. Several inhibitors of the phosphoinositide 3-kinase (PI(3)K)-Akt-mTOR signaling pathway are currently being evaluated in clinical phase II and III studies for the treatment of NETs with promising results. However, the molecular mechanisms and particularly the role of different Akt isoforms in NET signaling are not fully understood. In this study, we examine the effect of Akt inhibition on NET cells of heterogeneous origin. We show that the Akt inhibitor perifosine effectively inhibits Akt phosphorylation and cell viability in human pancreatic (BON1), bronchus (NCI-H727), and midgut (GOT1) NET cells. Perifosine treatment suppressed the phosphorylation of Akt downstream targets such as GSK3α/β, MDM2, and p70S6K and induced apoptosis. To further investigate the role of individual Akt isoforms for NET cell function, we specifically blocked Akt1, Akt2, and Akt3 via siRNA transfection. In contrast to Akt2 knockdown, knockdown of Akt isoforms 1 and 3 decreased phosphorylation levels of GSK3α/β, MDM2, and p70S6K and suppressed NET cell viability and colony-forming capacity. The inhibitory effect of simultaneous downregulation of Akt1 and Akt3 on tumor cell viability was significantly stronger than that caused by downregulation of all Akt isoforms, suggesting a particular role for Akt1 and Akt3 in NET signaling. Akt3 siRNA-induced apoptosis while all three isoform-specific siRNAs impaired BON1 cell invasion. Together, our data demonstrate potent antitumor effects of the pan-Akt inhibitor perifosine on NET cells in vitro and suggest that selective targeting of Akt1 and/or Akt3 might improve the therapeutic potential of Akt inhibition in NET disease.
Topics: Apoptosis; Bronchial Neoplasms; Cell Cycle; Cell Line, Tumor; Cell Survival; DNA Fragmentation; Humans; Intestinal Neoplasms; Neoplasm Invasiveness; Neuroendocrine Tumors; Pancreatic Neoplasms; Phosphorylcholine; Protein Isoforms; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-akt; RNA, Small Interfering
PubMed: 22499437
DOI: 10.1530/ERC-12-0074 -
Neoplasma 2012P-glycoprotein (P-gp)-mediated multidrug resistance (MDR) is the major clinical impediment to chemotherapy of breast cancers. Down-regulation of PI3K/Akt pathway has...
Perifosine downregulates MDR1 gene expression and reverses multidrug-resistant phenotype by inhibiting PI3K/Akt/NF-κB signaling pathway in a human breast cancer cell line.
P-glycoprotein (P-gp)-mediated multidrug resistance (MDR) is the major clinical impediment to chemotherapy of breast cancers. Down-regulation of PI3K/Akt pathway has been described as related to reversal of MDR in cancer cells. Here, we investigated the reversal effect on MDR phenotype of perifosine, a new Akt inhibitor, in breast cancer cell lines. In this study, MCF-7/ADM cells and MCF-7 cells were treated with different concentrations of perifosine. Our results suggested that perifosine reversed MDR partially by downregulation of P-gp expression and inhibition of PI3K/Akt/NF-κB pathway in the MCF-7/ADM cell line. The novel Akt inhibitor perifosine may be a promising new drug due to its ability to reverse MDR in human breast cancer cells.
Topics: ATP Binding Cassette Transporter, Subfamily B; ATP Binding Cassette Transporter, Subfamily B, Member 1; Apoptosis; Blotting, Western; Breast Neoplasms; Cell Line, Tumor; Cell Nucleus; Cell Proliferation; Down-Regulation; Drug Resistance, Multiple; Drug Resistance, Neoplasm; Elafin; Female; Flow Cytometry; Gene Expression Regulation, Neoplastic; Humans; NF-kappa B; Phosphorylcholine; Proto-Oncogene Proteins c-akt; RNA, Messenger; Real-Time Polymerase Chain Reaction; Signal Transduction; Tumor Cells, Cultured
PubMed: 22329846
DOI: 10.4149/neo_2012_032 -
Molecular Cancer Research : MCR Nov 2009Medulloblastoma is the most common malignant cancer of the central nervous system in children. AKT kinases are part of a survival pathway that has been found to be...
Medulloblastoma is the most common malignant cancer of the central nervous system in children. AKT kinases are part of a survival pathway that has been found to be significantly elevated in medulloblastoma. This pathway is a point of convergence for many growth factors and controls cellular processes that are critical for tumor cell survival and proliferation. The alkyl-phospholipid perifosine [octadecyl-(1,1-dimethyl-4-piperidylio) phosphate] is a small molecule inhibitor in clinical trials in peripheral cancers which acts as a competitive inhibitor of AKT kinases. Medulloblastoma cell cultures were used to study the effects of perifosine response in preclinical studies in vitro. Perifosine treatment led to the rapid induction of cell death in medulloblastoma cell lines, with pronounced suppression of phosphorylated AKT in a time-dependent and concentration-dependent manner. LD(50) concentrations were established using viability assays for perifosine, cisplatin, and etoposide. LD(50) treatment of medulloblastoma cells with perifosine led to the cleavage of caspase 9, caspase 7, caspase 3, and poly-ADP ribosylation protein, although caspase 8 was not detectable. Combination single-dose treatment regimens of perifosine with sublethal doses of etoposide or irradiation showed a greater than additive effect in medulloblastoma cells. Lower perifosine concentrations induced cell cycle arrest at the G(1) and G(2) cell cycle checkpoints, accompanied by increased expression of the cell cycle inhibitor p21(cip1/waf1). Treatment with p21 small interfering RNA prevented perifosine-induced cell cycle arrest. These findings indicate that perifosine, either alone or in combination with other chemotherapeutic drugs, might be an effective therapeutic agent for the treatment of medulloblastoma.
Topics: Antineoplastic Agents; Apoptosis; Blotting, Western; Cell Cycle; Cell Line, Tumor; Cell Survival; Cerebellar Neoplasms; Child; Cyclin-Dependent Kinase Inhibitor p21; Etoposide; Humans; Isoenzymes; Medulloblastoma; Phosphorylcholine; Proto-Oncogene Proteins c-akt; RNA, Small Interfering; Transfection
PubMed: 19887560
DOI: 10.1158/1541-7786.MCR-09-0069