Trigger Cell Apoptosis Research Articles

A high-throughput screening identifies histone deacetylase inhibitors as therapeutic agents against medulloblastoma

BackgroundMedulloblastoma is the most frequently occurring malignant brain tumor in children. Current treatment strategies for medulloblastoma include aggressive surgery, cranio-spinal irradiation and adjuvant chemotherapy. Because current treatments can cause severe long-term side effects and are not curative, successful treatment remains a challenge.MethodsIn this study, we employed a high-throughput cell viability assay to screen 12,800 compounds and to identify drug candidates with anti-proliferative properties for medulloblastoma cells. We also tested these compounds for attenuating medulloblastoma tumor development using mouse xenografts.ResultsWe identified two histone deacetylase inhibitors (dacinostat and quisinostat) with anti-proliferative properties for medulloblastoma cells. We showed that both compounds induce cytotoxicity, trigger cell apoptosis, and block cell cycle progression at the G2/M phase. In addition, dacinostat and quisinostat attenuated xenograft medulloblastoma growth in mice.ConclusionsOur findings suggest that histone deacetylase inhibitors are potent therapeutic agents against medulloblastoma.

Effect of Active Compound of Pasak Bumi Root (Euricoma longifolia, Jack) as an inhibitor of CDK2 methylation: In Silico Study

Active compound of Pasak Bumi’s root, a native plant of Indonesia, is used as antitumor by triggering cell apoptosis and reactivating the silence tumor suppressor gene caused by hypermethylation, inhibiting cancer cell proliferation. The aim of this study is to know the role of quassinoid from Pasak Bumi’s root (Eurycoma longifolia Jack) as an inhibitor of CDK2 methylation in silico. This is a descriptive study. CDK2 samples are obtained from Protein Data Bank (RSCB.org) with ID3SWR, samples of natural quassinoid are obtained from PUBCHEM NCBI and controlled by Sunitinib (®Sutent). Autodock Vina program PyRx 0.8 is used to analyze Molecular Docking. The process of analyzing molecular interactions is carried out using the LigandScout V.2.0 program. Visualization process are carried out using LigandScout V.2.0 program. The affinity of quassinoid and sutinab to CDK are -6.1 and -9.4, respectively. The more negative the binding affinity value, the better the ability of the compound (ligand) to bind to the receptor (macromolecules). From this case, Sutinab has better value compared to quassinoid. Target protein analysis using HITPICK shows quassinoid’s target predictor is JUN protein. Protein interaction analysis are obtained, and the compound is using stitch. JUN protein and Sunitib could bind with CDK2. The conclusion of this study is Sutinib has greater affinity compared to quassinoid.

Ectopic expression of BIRC5-targeting miR-101-3p overcomes bone marrow stroma-mediated drug resistance in multiple myeloma cells

BackgroundMultiple myeloma (MM) cells gain protection against drugs through interaction with bone marrow stromal cells (BMSCs). This form of resistance largely accounts for resistance to therapy in MM patients which warrants further exploration to identify more potential therapeutic targets.MethodsWe performed miRNA/mRNA qPCR arrays and western blotting to analyze transcriptional and translational changes in MM cells co-cultured with BMSCs. Drug cytotoxicity and apoptosis in MMGFP-BMSC co-cultures were measured using fluorescence plate reader and flowcytometry, respectively. miRNA was overexpressed in MM cell lines using Lentiviral transduction, miRNA-3’UTR binding was examined using luciferase assay.ResultsWe found that BMSCs downregulated miR-101-3p and upregulated survivin (BIRC5) in MM cells. Survivin was downregulated by miR-101-3p overexpression and found to be a direct target of miR-101-3p using 3’UTR luciferase assay. Overexpression of survivin increased viability of MM cells in the presence of anti-myeloma drugs, and miR-101-3p inhibition by anti-miR against miR-101-3p upregulated survivin. Furthermore, overexpression of miR-101-3p or silencing of survivin triggered apoptosis in MM cells and sensitized them to anti-myeloma drugs in the presence of BMSCs overcoming the stroma-induced drug resistance.ConclusionsOur study demonstrates that BMSC-induced resistance to drugs is associated with survivin upregulation which is a direct target of miR-101-3p. This study also identifies miR-101-3p-survivin interaction as a druggable target involved in stroma-mediated drug resistance in MM and suggests it for developing more efficient therapeutic strategies.

The effects of photodynamic therapy on leukemia cells mediated by KillerRed, a genetically encoded fluorescent protein photosensitizer

BackgroundLeukemia is a cancer of blood and bone marrow cells, causing about 300,000 deaths worldwide. Photodynamic therapy (PDT) is a promising alternative for the treatment of malignant tumors. KillerRed is a genetically encoded red fluorescent protein photosensitizer (PS). In this study, we aimed to investigate the effects of KillerRed-mediated PDT on chronic myelogenous leukemia K562 cells, acute monocytic leukemia NB4 cells, and acute monocytic leukemia THP1 cells.MethodsKillerRed was expressed in Escherichia coli cells, purified by Q-Sepharose column, and confirmed by western-blotting. The PDT effect on cell proliferation was evaluated by Cell Counting Kit-8 (CCK-8). Cell apoptosis was determined by PE Annexin V/7-AAD staining and flow cytometry. The distribution of KillerRed in leukemia cells was detected by confocal laser scanning microscopy (CLSM) and western-blotting. The ROS generation was measured by flow cytometry.ResultsPure KillerRed was obtained with a yield of about 37 mg per liter of bacterial cells. KillerRed photodynamic inactivated the leukemia cells in a concentration-dependent manner, but exhibited no obvious dark toxicity. PDT mediated by KillerRed could also induce apoptotic response (mainly early apoptosis) in the three cell lines. The CLSM imaging indicated that KillerRed was distributed within the cytoplasm and nuclei of leukemia cells, causing damages to the cytoplasm and leaving the nuclear envelope intact during light irradiation. KillerRed distributed both in the cytosol and nuclei was confirmed by western blotting, and ROS significantly increased in PDT treated cells compared to the cells treated with KillerRed alone.ConclusionsOur studies demonstrated that KillerRed-mediated PDT could effectively inactivate K562, NB4, and THP1 leukemia cells and trigger cell apoptosis, and it has potential to be used individually or complementally, in the treatment of leukemia.

LncRNA PART1 modulates chondrocyte proliferation, apoptosis, and extracellular matrix degradation in osteoarthritis via regulating miR-373-3p/SOX4 axis.

Osteoarthritis (OA) is a common disease in articular cartilages. It has been reported that long non-coding RNAs (lncRNAs) play an important role in various pathological processes of OA. However, the role of PART1 in OA development is unclear. The expression levels of PART1 and miR-373-3p were detected in cartilage tissues and chondrocytes using quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Cell proliferation was assessed by Cell Counting Kit-8 (CCK-8) assay. Cell apoptosis was determined by flow cytometry and Western blot assay. The expression of extracellular matrix (ECM)-related proteins was examined by Western blot assay. Expression of SRY-related high-mobility group box 4 (SOX4) was measured by qRT-PCR or Western blot assay. The interactions among PART1, miR-373-3p, and SOX4 were predicted using starBase v2.0 database and confirmed by Dual-Luciferase reporter assay and RNA immunoprecipitation (RIP) assay. PART1 and SOX4 were up-regulated while miR-373-3p was down-regulated in OA cartilage tissues and chondrocytes. PART1 silencing hindered cell proliferation and ECM degradation, and triggered cell apoptosis in OA chondrocytes. PART1 modulated SOX4 expression by targeting miR-373-3p. Inhibition of miR-373-3p restored the regulation of cell proliferation, ECM degradation, and apoptosis induced by interfering PART1. Upregulation of SOX4 restored the effects on OA progression induced by inhibiting PART1. PART1 promoted OA progression by regulating miR-373-3p/SOX4 axis, providing an effective therapeutic target for osteoarthritis.

Ganoderic acid A holds promising cytotoxicity on human glioblastoma mediated by incurring apoptosis and autophagy and inactivating PI3K/AKT signaling pathway

Ganoderic acid A (GA-A), recognized as a lanostanetriterpene isolated from Ganoderma lucidum, demonstrates an efficient antitumor activity in multiple cancers. To date, it is unclear whether and how GA-A functions on human glioblastoma (GBM). To unravel the functional significance of GA-A on human glioblastoma (GBM), the cell-counting kit-8 and transwell assays were used to detect proliferation, migration, and invasion of human GBM cell after GA-A treatment. Then, we utilized the flow cytometry and western blot to further evaluate the effect of GA-A on GBM cell. Further, activities of autophagy and PI3K/AKT signaling were assessed by Western blot assay. We found that GA-A significantly inhibited proliferation, migration, and invasion of GBM cell. Additionally, GA-A markedly triggered cell apoptosis, which incarnated an elevation trend in apoptotic percentage, simultaneously, an increased level of proapoptosis protein (Bax and active caspase-3) and a decreased level of antiapoptosis protein (Bcl-2), induced by GA-A treatment. Meanwhile, levels of two well-known autophagy markers (beclin 1 and LC3 II) increased while another autophagic substrate (P-62) was reduced. Moreover, the expressions levels of phosphorylated AKT, mTOR, p-P70S6K, and cyclin D1 in the PI3K/AKT pathway were significantly reduced, which revealed GA-A repressed the activation of PI3K/AKT signaling pathway. Collectively, these results indicate that GA-A may encourage U251 cell growth and invasion/migration inhibition, apoptosis, and autophagy through the inactivation of PI3K/AKT signaling pathway in human GBM. Hence, GA-A may be a potent antitumorigenic agent for human GBM in future clinical practice.

FAK activity sustains intrinsic and acquired ovarian cancer resistance to platinum chemotherapy.

Gene copy number alterations, tumor cell stemness, and the development of platinum chemotherapy resistance contribute to high-grade serous ovarian cancer (HGSOC) recurrence. Stem phenotypes involving Wnt-β-catenin, aldehyde dehydrogenase activities, intrinsic platinum resistance, and tumorsphere formation are here associated with spontaneous gains in Kras, Myc and FAK (KMF) genes in a new aggressive murine model of ovarian cancer. Adhesion-independent FAK signaling sustained KMF and human tumorsphere proliferation as well as resistance to cisplatin cytotoxicity. Platinum-resistant tumorspheres can acquire a dependence on FAK for growth. Accordingly, increased FAK tyrosine phosphorylation was observed within HGSOC patient tumors surviving neo-adjuvant chemotherapy. Combining a FAK inhibitor with platinum overcame chemoresistance and triggered cell apoptosis. FAK transcriptomic analyses across knockout and reconstituted cells identified 135 targets, elevated in HGSOC, that were regulated by FAK activity and β-catenin including Myc, pluripotency and DNA repair genes. These studies reveal an oncogenic FAK signaling role supporting chemoresistance.

Synthesis and in vitro antitumor activity evaluation of copper(II) complexes with 5-pyridin-2-yl-[1,3]dioxolo[4,5-g]isoquinoline derivatives

Seven Cu(II) complexes with 5-pyridin-2-yl-[1,3]dioxolo[4,5-g]isoquinoline derivatives as ligands: [Cu2(L1)2Cl4] (1), [Cu(L2)Cl2] (2), [Cu(L1)(NO3)2] (3), [Cu(L2)(NO3)2] (4), [Cu(L3)Cl2] (5), [Cu(L3)Br2] (6) and [Cu(L3)(NO3)2] (7){L1=9-nitro-5-pyridin-2-yl-[1,3]dioxolo[4,5-g]isoquinoline, L2=4-nitro-5-pyridin-2-yl-[1,3]dioxolo[4,5-g]isoquinoline, L3=9-bromo-5-pyridin-2-yl-[1,3]dioxolo[4,5-g]isoquinoline}, were synthesized and characterized. Their in vitro anticancer activities against T-24, MGC-80-3, HeLa, Hep-G2, A549 and SK-OV-3 were evaluated. Compared with their corresponding ligands, most of these complexes exhibited enhanced anticancer activities in contrast to their corresponding ligands and copper salt. Among them, complexes 1 and 3 displayed selective cytotoxicity to HeLa cells comparing with normal liver cell HL-7702, with IC50 values of 5.03 ± 1.20 μM and 10.05 ± 0.52 μM, respectively. Complexes 1 and 3 inhibited telomerase activity by interacting with c-myc promoter elements, and therefore exerted their antitumor activity. Furthermore, complexes 1 and 3 could trigger cell apoptosis via disruption of mitochondrial pathway through notably increased reactive oxygen species (ROS) levels, loss of mitochondrial membrane potential (Δψm), increase of the cytochrome c and apaf-1, decrease of bcl-2, and activation of caspases 3/9. Complexes 1 and 3 exhibited enhanced cytotoxicity, presenting synergetic effect after the ligands coordinated to copper(II) center.

Cardiac troponin I autoantibody induces myocardial dysfunction by PTEN signaling activation.

BackgroundThe objective of the current study was to study the molecular mechanism(s) underlying cardiac troponin I autoantibody (cTnIAAb) binding to cardiomyocyte and resultant myocardial damage/dysfunction.MethodscTnIAAb was purified from serum of 10 acute myocardial infarction (AMI) patients with left ventricular remodeling. Recombinant human cTnI was used to generate three mouse-derived monoclonal anti-cTnI antibodies (cTnImAb1, cTnImAb2, and cTnImAb3). The target proteins in cardiac myocyte membrane bound to cTnImAb and effect of cTnIAAb and cTnImAb on apoptosis and myocardial function were determined.FindingsWe found that cTnIAAb/cTnImAb1 directly bound to the cardiomyocyte membraneα-Enolase (ENO1) and triggered cell apoptosis via increased expression of ENO1 and Bax, decreased expression of Bcl2, subsequently activating Caspase8, Caspase 3, phosphatase and tensin homolog (PTEN) while inhibiting Akt activity. This cTnIAAb-ENO1-PTEN-Akt signaling axis contributed to increased myocardial apoptosis, myocardial collagen deposition, and impaired systolic dysfunction.InterpretationResults obtained in this study indicate that cTnIAAb is involved in the process of ventricular remodeling after myocardial injury.FundThe National Natural Science Foundation of China (Grant#: 81260026).

Doxorubicin-loaded functionalized selenium nanoparticles for enhanced antitumor efficacy in cervical carcinoma therapy.

Development of novel tumor-targeted drug vehicles for cancer therapy is very important and has become one of major topics for designing nanoscale chemotherapeutics delivery systems. In the present study, selenium nanoparticles (SeNPs) was decorated with hyaluronic acid (HA) to prepare HA-SeNPs nanoparticles which were used to load doxorubicin (DOX) to fabricate tumor-targeted functionalized selenium nanoparticles HA-Se@DOX. In vitro and in vivo antitumor activities of HA-Se@DOX in human cervical carcinoma treatment were investigated. HA-Se@DOX showed selective cellular uptakes between cervical cancer HeLa cells and human umbilical vein endothelial cells (HUVEC). In vitro release result indicated that DOX was released from HA-SeNPs faster in acidic environment in comparison with normal physiological environment and 76.9% DOX was released in pH 5.4 during initial 30 h. HA-Se@DOX showed high activity to inhibit HeLa cell proliferation and triggered HeLa cell apoptosis via activating Bcl-2 signaling pathway. In vivo antitumor study showed that HA-Se@DOX inhibited tumor growth through suppressing cancer cells proliferation and inducing cancer cells apoptosis. Interestingly, HA-Se@DOX exhibited stronger anticancer activity than free DOX and Se@DOX in vitro and in vivo. Additionally, HA-Se@DOX did not cause damage to major organs at the used dose. HA-Se@DOX is a promising antitumor agent for human cervical carcinoma treatment and this research provides a novel therapeutic strategy for cancer therapy.

Identification of a 5-Hydroxymethylfurfural-Lysine Schiff Base and Its Cytotoxicity in Three Cell Lines.

5-Hydroxymethylfurfural (HMF) can undergo the Maillard reaction with amino acids. However, the safety of the products remains unknown. In this study, a HMF-lysine Schiff base named (E)-N6-((5'-(hydroxymethyl)furan-2'-yl)methylene)lysine (HML) was identified and detected for the first time in baked foods. HML formation significantly decreased the cytotoxicity (IC50) of HMF against GES-1 cells (81.81 versus 5.02 mM and 73.76 versus 2.94 mM for HML versus HMF at 24 and 48 h, respectively), EA.hy926 cells (86.05 versus 4.85 mM and 77.22 versus 0.71 mM, respectively), and Caco-2 cells (155.77 versus 36.84 mM and 112.70 versus 18.51 mM, respectively). Exposure of Caco-2 cells to HMF at 10.0 mM triggered cell apoptosis of 14.02% (versus 8.54% in the control), whereas exposure to HML at 10-15 mM hardly increased cell apoptosis. Moreover, the absorption capacities of HMF and HML by Caco-2 cells were equivalent (p > 0.05) at 7.23-12.57% after incubation at 2 mM for 30-150 min.

Short-term developmental toxicity and potential mechanisms of the herbicide metamifop to zebrafish (Danio rerio) embryos

Metamifop is a novel aryloxyphenoxy propionate (AOPP) herbicide that is widely applied in paddy fields, which will inevitably enter aquatic environments and pose a risk to aquatic organisms. However, the potential threat and toxicological mechanisms of metamifop in aquatic organisms are poorly understood. In this study, zebrafish embryos were used to investigate the potential developmental toxicity and mechanisms of metamifop. The results showed that metamifop exhibited high acute toxicity to zebrafish, with 96 h-LC50 values of 0.648 and 0.216 mg/L to embryos and larvae of 72 h post-hatching (hph), respectively. Decreased body lengths, heartbeat number, and hatching rates, and increased malformation rates of embryos were observed after 96 h of exposure to 0.38 mg/L or higher concentration of metamifop. Furthermore, oxidative stress was caused in embryos, with increased contents of reactive oxygen species (ROS) and malondialdehyde (MDA), and altered activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx). Metamifop exposure clearly triggered cell apoptosis in embryos, result in the increase of Caspase-3 and Caspase-9 activities and up-regulation of apoptosis-related genes (bax, p53, apaf1, caspase-3, and caspase-9). Additionally, the transcriptions of innate immune-related genes (il-8, il-1b, and ifn) were increased in the groups treated with 0.25 and 0.5 mg/L of metamifop. These results indicate that metamifop induced developmental toxicity in zebrafish, and the potential toxicological mechanisms were related to oxidative stress, cell apoptosis, and the innate immune responses in embryos.

The Novel Nature Microtubule Inhibitor Ivalin Induces G2/M Arrest and Apoptosis in Human Hepatocellular Carcinoma SMMC-7721 Cells In Vitro.

Background and Objectives: Microtubules are an attractive target for cancer chemotherapy. Previously, we reported that Ivalin exhibited excellent anti-migration and anti-invasion activities in human breast cancer cells. Here, we examined the microtubule inhibition effect of Ivalin in human hepatocellular carcinoma SMMC-7721 cells. Materials and Methods: We used the 3-(4,5-dimethylthiazol)-2,5-diphenyltetrazolium bromide (MTT) assay to evaluate the cell proliferation effect of Ivalin and flow cytometry analysis to detect the apoptotic and cell cycle arrest effects of Ivalin. Immunofluorescence staining was used to measure the effect of Ivalin on the cytoskeleton network, and Western blotting was used to detect the expression levels of Bax, Bcl-2, Cdc2, phosphor-Cdc2, Cdc25A, Cyclin B1, and tubulin. Results: Ivalin induced cell cycle G2/M arrest and subsequent triggered apoptosis in human hepatocellular carcinoma SMMC-7721 cells. Furthermore, microtubules were shown to be involved in Ivalin-meditated apoptosis. In this connection, Ivalin treatment suppressed cellular microtubule network formation by regulating microtubule depolymerization. Moreover, Western blotting revealed Cdc25A and Cyclin B1 were upregulated in Ivalin-meditated cell cycle arrest. Subsequently, the induction of Bax (a proapoptotic protein) and reduction of Bcl-2 (an anti-apoptotic protein) expression were observed in Ivalin-treated SMMC-7721 cells. Conclusion: Ivalin induced microtubule depolymerization, then blocked cells in mitotic phase, and eventually resulted in apoptosis in SMMC-7721 cells. Collectively, these data indicate that Ivalin, acting as a novel inhibitor of microtubules, could be considered as a promising lead in anticancer drug development.

Pristimerin induces apoptosis and autophagy via activation of ROS/ASK1/JNK pathway in human breast cancer in vitro and in vivo

Breast cancer is the most common malignant tumor in women, and progress toward long-term survival has stagnated. Pristimerin, a natural quinonemethide triterpenoid, exhibits potential anti-tumor effects on various cancers. However, the underlying mechanism remains poorly understood. In this study, we found that pristimerin reduced the viability of breast cancer cells in vitro and the growth of xenografts in vivo, and these reductions were accompanied by thioredoxin-1 (Trx-1) inhibition and ASK1 and JNK activation. The results showed that pristimerin inhibited cell cycle progression and triggered cell apoptosis and autophagy. Furthermore, we found that the generation of reactive oxygen species (ROS) was a critical mediator in pristimerin-induced cell death. Enhanced ROS generation by pristimerin activated the ASK1/JNK signaling pathway. Inhibition of ROS with N-acetyl cysteine (NAC) significantly decreased pristimerin-induced cell death by inhibiting the phosphorylation of ASK1 and JNK. Taken together, these results suggest a critical role for the ROS/ASK1/JNK pathway in the anticancer activity of pristimerin.

Structural characterization and biological properties of silver(I) tris(pyrazolyl)methane sulfonate

The water-soluble 1D helical coordination polymer [Ag(Tpms)]n (1) [Tpms = tris(pyrazolyl)methane sulfonate, −O3SC(pz)3; pz = pyrazolyl] was synthesized and fully characterized, its single-crystal X-ray diffraction analysis revealing the ligand acting as a bridging chelate N3-donor ligand. The antiproliferative potential of 1 was performed on two human tumour cell lines, A2780 and HCT116, and in normal fibroblasts, with a much higher effect in the former cell line (IC50 of 0.04 μM) as compared to the latter cell line and to normal fibroblasts. Compound 1 does not alter cell cycle progression but interferes with the adherence of A2780 cells triggering cell apoptosis. Apoptosis appears to occur via the extrinsic pathway (no changes in mitochondria membrane potential, reactive oxygen species (ROS) and pro-apoptotic (B-cell lymphoma 2 (BCL-2) associated protein (BAX))/anti-apoptotic (BCL-2) ratio) being this hypothesis also supported by the presence of silver mainly in the supernatants of A2780 cells. Results also indicated that cell death via autophagy was triggered. Proteomic analysis allowed us to confirm that compound 1 is able to induce a stress response in A2780 cells that is related with its antiproliferative activity and the trigger of apoptosis.

Emodin Induced SREBP1-Dependent and SREBP1-Independent Apoptosis in Hepatocellular Carcinoma Cells.

Reynoutria multiflora (Thunb.) Moldenke (He Shou Wu) has been used for about 20 centuries as a Chinese medicinal herb for its activities of anticancer, anti-hyperlipidemia, and anti-aging. Previously, we found that He Shou Wu ethanol extract could induce apoptosis in hepatocellular carcinoma cells, and we also screened its active components. In this study, we investigated whether lowering lipid metabolism of emodin, a main active component in He Shou Wu, was associated with inhibitory effects in hepatocellular carcinoma cells. The correlation of apoptosis induction and lipid metabolism was investigated. The intrinsic apoptotic cell death, lipid production, and their signaling pathways were investigated in emodin-treated human hepatocellular carcinoma cells Bel-7402. The data showed that emodin triggered apoptosis in Bel-7402 cells. The mitochondrial membrane potential (ΔΨm) was reduced in emodin-treated Bel-7402 cells. We also found that emodin activated the expression of intrinsic apoptosis signaling pathway-related proteins, cleaved-caspase 9 and 3, Apaf 1, cytochrome c (CYTC), apoptosis-inducing factor, endonuclease G, Bax, and Bcl-2. Furthermore, the level of triglycerides and desaturation of fatty acids was reduced in Bel-7402 cells when exposed to emodin. Furthermore, the expression level of messenger RNA (mRNA) and protein of sterol regulatory element binding protein 1 (SREBP1) as well as its downstream signaling pathway and the synthesis and the desaturation of fatty acid metabolism-associated proteins (adenosine triphosphate citrate lyase, acetyl-CoA carboxylase alpha, fatty acid synthase (FASN), and stearoyl-CoA desaturase D) were also decreased. Notably, knock-out of SREBP1 in Bel-7402 cells was also found to induce less intrinsic apoptosis than did emodin. In conclusion, these results indicated that emodin could induce apoptosis in an SREBP1-dependent and SREBP1-independent manner in hepatocellular carcinoma cells.

Inhibition of cancer cell proliferation by adenosine triphosphate-triggered codelivery system of p53 gene and doxorubicin

The codelivery of drugs and genes by stimuli-responsive nanocarriers is a promising strategy for achieving an effective cancer treatment. In this study, an adenosine triphosphate (ATP)-responsive nanosystem was constructed to codeliver doxorubicin (DOX) and p53 gene based on an ATP-triggered aptamer and polyethyleneimine (PEI). In this system, DOX interacts with the GC-rich motif of duplex formed by the aptamer and its cDNA sequence. Then, a ternary nanocomplex DOX-Duplex/PEI/p53 was constructed using cationic carrier PEI25K for facilitating the intracellular delivery and release of p53 gene and DOX. The DOX-Duplex/PEI/p53 nanocomplex was found to possess an efficient anticancer effect, which was attributed to the ability of the system to trigger cell apoptosis and meanwhile block the cell cycle at G2 phase. The favorable antiproliferative effect was found to be associated with the rapid DOX and p53 gene release in response to the intracellular ATP concentration and the synergistic effect of therapeutic drug and gene.

A study on regulatory mechanism of miR-223 in ulcerative colitis through PI3K/Akt-mTOR signaling pathway.

The aim of this study was to explore the regulatory mechanism of micro ribonucleic acid (miR)-223 in ulcerative colitis (UC) through the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)-mammalian target of rapamycin (mTOR) signaling pathway. A total of 36 Sprague-Dawley (SD) rats were randomly divided into three groups, including normal group (n=12), model group (n=12) and inhibitor group (n=12). Rats in the normal group received no treatment. Rats in the model group were used to establish a UC model. Meanwhile, rats in the inhibitor group underwent intraperitoneal injection of inhibitor and establishment of the UC model. Subsequently, specimens were obtained for detection. Immunohistochemistry was applied to measure the expression of mTOR. Western blotting was adopted to determine the relative protein expressions of P85, P110 and phosphorylated Akt (p-Akt). Quantitative polymerase chain reaction (qPCR) was used to detect the mRNA expression of miR-223. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) was utilized to determine cell apoptosis. Furthermore, an enzyme-linked immunosorbent assay (ELISA) was conducted to measure the content of interleukin-1 beta (IL-1β) and IL-6. Immunohistochemistry showed that the positive expression of mTOR increased remarkably in the model group and inhibitor group when compared with that of the normal group (p<0.05). However, it decreased notably in the inhibitor group when compared with the model group (p<0.05). Western blotting indicated that the protein expressions of P85, P110 and p-Akt in model group and inhibitor group were significantly higher than the ones of the normal group (p<0.05). However, the inhibitor group showed markedly lower relative protein expressions of P85, P110 and p-Akt than the ones of the model group (p<0.05). Compared with the normal group, the expression level of miR-223 was significantly elevated in model group and inhibitor group (p<0.05). However, there was no significant difference in the mRNA expression of miR-233 between the model group and the inhibitor group (p>0.05). The apoptosis rate of the cells increased prominently in the model group and in the inhibitor group when compared with the normal group (p<0.05). However, it was remarkably reduced in the inhibitor group than the model group (p<0.05). In comparison with the normal group, the content of IL-1β and IL-6 was significantly up-regulated in the model group and in the inhibitor group (p<0.05). However, it declined notably in the inhibitor group compared with the model group (p<0.05). MiR-223 can trigger cell apoptosis and inflammation in UC by up-regulating the PI3K/Akt-mTOR signaling pathway.

KPC1 alleviates hypoxia/reoxygenation-induced apoptosis in rat cardiomyocyte cells though BAX degradation.

Bax triggers cell apoptosis by permeabilizing the outer mitochondrial membrane, leading to membrane potential loss and cytochrome c release. However, it is unclear if proteasomal degradation of Bax is involved in the apoptotic process, especially in heart ischemia‐reperfusion (I/R)‐induced injury. In the present study, KPC1 expression was heightened in left ventricular cardiomyocytes of patients with coronary heart disease (CHD), in I/R‐myocardium in vivo and in hypoxia and reoxygenation (H/R)‐induced cardiomyocytes in vitro. Overexpression of KPC1 reduced infarction size and cell apoptosis in I/R rat hearts. Similarly, the forced expression of KPC1 restored mitochondrial membrane potential (MMP) and cytochrome c release driven by H/R in H9c2 cells, whereas reducing cell apoptosis, and knockdown of KPC1 by short‐hairpin RNA (shRNA) deteriorated cell apoptosis induced by H/R. Mechanistically, forced expression of KPC1 promoted Bax protein degradation, which was abolished by proteasome inhibitor MG132, suggesting that KPC1 promoted proteasomal degradation of Bax. Furthermore, KPC1 prevented basal and apoptotic stress‐induced Bax translocation to mitochondria. Bax can be a novel target for the antiapoptotic effects of KPC1 on I/R‐induced cardiomyocyte apoptosis and render mechanistic penetration into at least a subset of the mitochondrial effects of KPC1.

Combination treatment strategy for pancreatic cancer involving the novel HDAC inhibitor MPT0E028 with a MEK inhibitor beyond K-Ras status.

BackgroundOncogenic K-Ras signaling highly relies on the canonical Ras/MEK/ERK pathway to contribute to pancreatic cancer progression. However, numerous efforts of MEK inhibitors have failed to provide an optimal antitumor effect for pancreatic cancer in practice. The aim of the present work was to develop a more efficacious therapeutic intervention for MEK inhibitors through combination with histone deacetylase (HDAC) inhibitor MPT0E028.MethodsThe effects of combined therapy on cell viability, apoptosis, protein, and RNA expressions were determined by MTT assay, flow cytometry, western blotting, and quantitative PCR analysis. The AsPC-1 xenograft was used to assess antitumor effects in vivo.ResultsThe co-administration of MPT0E028 and MEK inhibitor yielded synergistic effects on cell viability suppression both in K-Ras mutated and wild-type pancreatic cancer cells and also markedly triggered cell apoptosis. Surprisingly, ERK and epidermal growth factor receptor (EGFR) were activated by the long-term and low-concentration treatment of MPT0E028 or another HDAC inhibitor alone. Whereas, the pharmacological attenuation of ERK signaling dramatically abolished the MPTE028-induced p-ERK and EGFR expression. Overexpression of HDAC4, HDAC6, and MEK, respectively, reversed the cell death induced by the combined treatment. Finally, the combined treatment decreased the tumor volume in an AsPC-1 xenograft model compared to each individual treatment alone.ConclusionsThe synergistic anti-survival effect of the combination was suggested to occur via compensation of the MEK inhibitor for activated ERK. Our results indicate that this combination strategy could benefit patients with pancreatic cancer beyond K-Ras status.