Mechanism Of Apoptosis Induction Research Articles

Antiproliferative activity and apoptosis-inducing mechanism of Curcuma longa (Turmimax®) on HeLa cell lines.

Curcumin, the primary polyphenol found in turmeric, is derived from the Curcuma longa plant. Since curcumin is nontoxic and has a wide range of medicinal qualities, including anti-oxidant, analgesic, anti-inflammatory, and antibacterial action, it has been widely employed in Ayurveda medicine for ages. Curcumin has recently been discovered to have anti-cancer properties through its impact on numerous biological pathways involved in carcinogenesis, metastasis, tumorigenesis, cell cycle regulation, mutagenesis, and oncogene expression. In this study, we determined the Antiproliferative activity and apoptosis-inducing mechanism of C. longa (Turmimax®) on human cancer cells. The cytotoxic effect was evaluated against HeLa cell lines using the MTT (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) assay. Flow cytometric analysis was performed to detect apoptotic cell death. Turmimax® exhibits promising properties as a potential anti-cancer therapeutic agent in human cervical adenocarcinomas and possibly other cancer types, with an IC50 value of 87.89 µg/mL. In HeLa cells treated with Turmimax®, cell cycle arrest was seen in the G0/G1 and S phases. By inducing apoptosis and increasing the number of apoptotic cells in a dose-dependent manner, the experimental data suggest that Turmimax® has considerable promise in cancer prevention and treatment.

Gold nanoparticles loaded TNF-α and CALNN peptide as a drug delivery system and promising therapeutic agent for breast cancer cells

ABSTRACT We investigated the anti-cancer properties of gold nanoparticles loaded TNF- and CALNN peptides, which we proposed as a potential drug delivery system using in vitro and in vivo models. The binding of GNPs-TNF- and GNPs-TNF-CALNN was characterized using a UV, ELISA and SEM analysis. The outcomes demonstrated that a novel drug delivery system had an anti-proliferative activity against breast cancer cell lines through a mechanism of apoptosis induction. In vivo model involved studying the cytotoxic influence of a drug delivery system GNPs, GNPs-TNF-α and GNPs-TNF-α-CALNN when applied to the transplanted AN-3 cell line. tumor sections were examined using microarray. In-vivo studies demonstrated that GNPs alone had less of a growth inhibitory effect on tumors implanted in mice when compared to GNPs-TNF – CALNN combined therapy. The cytotoxic assay showed that GNPs, GNPs-TNF-α and GNPs-TNF-α-CALNN exhibit selective toxicity towards cancer cells, inducing cell apoptosis through activation of caspase-3 and 7, p53 protein.

Apoptosis Detection Assays.

Many apoptosis assays are available since there are many proteins regulated at multiple points and involved in apoptosis signaling cascade. To detect apoptosis accurately, two or more assays should be used since there are many overlapped features between apoptosis and necrosis. There are six major groups of available assays to detect apoptosis: membrane alteration, mitochondrial assays, cytomorphological alterations, DNA fragmentation, detection of caspase, cleaved substrate, inhibitors and regulators, and detection of apoptosis in whole mounts. Among those assay, early apoptosis could be detected through annexin V, which is based on the loss of the cellular membrane integrity. Also, there are many assays that can detect midphase of apoptosis using caspase activation and molecular processing including PARP degradation. Late phase of apoptosis could be detected with DNA fragmentation assays. Combinations of these assays allow us to identify the mechanisms of apoptosis induction after specific stimulus. This chapter will introduce three apoptosis detection assays including annexin assay, DNA/chromatin condensation assays, and TUNEL assay.

The role of some lipids and their metabolites in programmed cell death (lipoapoptosis).

In recent years, the understanding of the mechanisms involved in the regulation of lipoapoptosis signaling pathways has expanded considerably. However, many mechanisms of apoptosis induction by lipids as well as molecules mediating intracellular and systemic signals belonging to AOS/enzyme-dependent phospholipid metabolites are not completely clear.This review summarizes the current understanding of the mechanisms of apoptotic cell death induction by some lipid molecules. Literature search was performed in the database “PubMed”, “eLIBRARY” using key words: “apoptosis”, “lipids”, “fatty acids”, “eicosanoids”, “reactive oxygen species”.A brief characterization of the signaling pathways of apoptosis is given. The role of reactive oxygen species and their dependent products of lipid peroxidation in the regulation of the main signaling pathways of apoptosis are shown. Particular attention is paid to the product of phospholipid metabolism – 4-hydroxynonenal.Pro- and anti-apoptotic effects of some prostaglandins are demonstrated. Arguments are presented that prostaglandins of series J and D are pro-apoptotic in most cells, and this effect depends on activation of the prostanoid receptor DP2 and on reduction of AKT kinase activity. In contrast, the E-series prostaglandins and hydroxyecosatetraenoic acid act opposite to the J-series and D-series prostaglandins, reducing apoptosis by activating AKT and increasing Bcl-2 protein expression.The role of individual fatty acids involved in the initiation and transduction of pro-apoptotic and anti-apoptotic signals is assessed. It was shown that saturated fatty acids have the maximum damaging potential than their unsaturated counterparts. An in-depth understanding and deciphering of the mechanisms by which lipids and their metabolites modulate the activation of signaling pathways of programmed cell death can help to develop therapeutic strategies to prevent a number of diseases associated with impaired regulation of apoptosis.

Eltanexor Effectively Reduces Viability of Glioblastoma and Glioblastoma Stem-Like Cells at Nano-Molar Concentrations and Sensitizes to Radiotherapy and Temozolomide.

Current standard adjuvant therapy of glioblastoma multiforme (GBM) using temozolomide (TMZ) frequently fails due to therapy resistance. Thus, novel therapeutic approaches are highly demanded. We tested the therapeutic efficacy of the second-generation XPO1 inhibitor Eltanexor using assays for cell viability and apoptosis in GBM cell lines and GBM stem-like cells. For most GBM-derived cells, IC50 concentrations for Eltanexor were below 100 nM. In correlation with reduced cell viability, apoptosis rates were significantly increased. GBM stem-like cells presented a combinatorial effect of Eltanexor with TMZ on cell viability. Furthermore, pretreatment of GBM cell lines with Eltanexor significantly enhanced radiosensitivity in vitro. To explore the mechanism of apoptosis induction by Eltanexor, TP53-dependent genes were analyzed at the mRNA and protein level. Eltanexor caused induction of TP53-related genes, TP53i3, PUMA, CDKN1A, and PML on both mRNA and protein level. Immunofluorescence of GBM cell lines treated with Eltanexor revealed a strong accumulation of CDKN1A, and, to a lesser extent, of p53 and Tp53i3 in cell nuclei as a plausible mechanism for Eltanexor-induced apoptosis. From these data, we conclude that monotherapy with Eltanexor effectively induces apoptosis in GBM cells and can be combined with current adjuvant therapies to provide a more effective therapy of GBM.

Cellular Regulation of Kynurenic Acid-Induced Cell Apoptosis Pathways in AGS Cells.

Kynurenic acid was included in the three compounds (caffeic acid, chlorogenic acid, and kynurenic acid) that showed high antioxidant and anti-inflammatory potential among the phenolic compounds contained in Gynura procumbens. In this study, the mechanism of cancer cell death induced by kynurenic acid (KYNA), which has the highest molecular binding affinity, in the gastric cancer cell line AGS was confirmed in molecular docking analysis. KYNA showed the most cancer cell death effect on AGS cells among several gastric cancer cell lines (MKN, AGS, and SNU). AGS cells were used for later experiments, and KYNA concentrations of 0, 150, 200, and 250 µM were used. KYNA inhibited cell migration and proliferation in AGS cells in a concentration-dependent manner. G2/M phase cell cycle arrest and reduction of related proteins (Cdc25C, CDK1 and CyclinB1) were confirmed in KYNA-treated AGS cells. Apoptosis of KYNA-treated AGS cells was confirmed by Annexin V/propidium iodide (PI) staining flow cytometry analysis. As a result of morphological chromatin condensation through DAPI (4′,6-diamidino-2-phenylindole), intense blue fluorescence was confirmed. The mechanism of apoptosis induction of KYNA-treated AGS cells was confirmed by western blotting. In the extrinsic pathway, apoptosis induction markers FasL, Fas, and Caspase-3 and -8 were increased in a concentration-dependent manner upon KYNA treatment. In the intrinsic pathway, the expression of anti-apoptotic factors PI3K, AKT, and Bcl-xL was down-regulated, and the expression of apoptosis-inducing factors BAD, Bak, Bax, Cytochrom C, and Caspase-9 was up-regulated. Therefore, in the present study, we strongly imply that KYNA induces apoptosis in AGS gastric cancer cells. This suggests that KYNA, a natural compound, could be the basis for drug for the treatment of gastric cancer.

Bioinformatics Analysis Reveals FOXM1/BUB1B Signaling Pathway as a Key Target of Neosetophomone B in Human Leukemic Cells: A Gene Network-Based Microarray Analysis.

Abnormal expression of Forkhead box protein M1 (FOXM1) and serine/threonine kinase Budding uninhibited by benzimidazoles 1 (BUB1B) contributes to the development and progression of several cancers, including chronic myelogenous leukemia (CML). However, the molecular mechanism of the FOXM1/BUB1B regulatory network and the role of Neosetophomone-B (NSP-B) in leukemia remains unclear. NSP-B, a meroterpenoid fungal secondary metabolite, possesses anticancer potential in human leukemic cells lines; however, the underlying mechanism has not been elucidated. The present study aimed to explore the role of NSP-B on FOXM1/BUB1B signaling and the underlying molecular mechanism of apoptosis induction in leukemic cells. We performed gene expression profiling of NSP-B-treated and untreated leukemic cells to search for differentially expressed genes (DEGs). Interestingly BUB1B was found to be significantly downregulated (logFC -2.60, adjusted p = 0.001) in the treated cell line with the highest connectivity score among cancer genes. Analysis of TCGA data revealed overexpression of BUB1B compared to normal in most cancers and overexpression was associated with poor prognosis. BUB1B also showed a highly significant positive correlation with FOXM1 in all the TCGA cancer types. We used human leukemic cell lines (K562 and U937) as an in vitro study model to validate our findings. We found that NSP-B treatment of leukemic cells suppressed the expression of FOXM1 and BUB1B in a dose-dependent manner. In addition, NSP-B also resulted in the downregulation of FOXM1-regulated genes such as Aurora kinase A, Aurora kinase B, CDK4, and CDK6. Suppression of FOXM1 either by siRNA or NSP-B reduced BUB1B expression and enhanced cell survival inhibition and induction of apoptosis. Interestingly combination treatment of thiostrepton and NSP-B suppressed of cell viability and inducted apoptosis in leukemic cells via enhancing the activation of caspase-3 and caspase-8 compared with single-agent treatment. These results demonstrate the important role of the FOXM1/BUB1B pathway in leukemia and thus a potential therapeutic target.

Green synthesized zinc oxide nanoparticles induce apoptosis by suppressing PI3K/Akt/mTOR signaling pathway in osteosarcoma MG63 cells

This study aimed to assess the apoptosis-inducing mechanism of zinc oxide nanoparticles (ZnO NPs) stabilized by Solanum xanthocarpum plant extract in human osteosarcoma MG63 cells. In the present study, we synthesized ZnO NPs from S. xanthocarpum extract and evaluated its anticancer mechanism on MG 63 cells. The synthesized ZnO NPs were characterized by ultraviolet spectroscopy, X-ray crystallography, transmission electron microscopy, energy dispersive X-ray, and Fourier-transform infrared spectroscopy analysis. The mean size of the synthesized ZnO NPs was 21.62 ± 7.45 nm and spherical in shape. The cytotoxicity of ZnO NPs on MG63 cells was determined by MTT assay. The Western blot analysis was carried out to examine the expression of apoptotic and autophagy-related proteins in MG63 cells. The findings of the study reveal that ZnO NPs treatment showed concentration-dependent cytotoxicity, increased lipid peroxidation, decreased antioxidant activity, increased reactive oxygen species generation, and increased DNA damage. In addition, ZnO NPs treatment increased the expression of apoptotic members such as p53, Bax, caspase-3, -8, and -9 while downregulating Bcl-2 expression in MG63 cells. Furthermore, ZnO NPs treatment suppressed the P13K/AKT/mTOR signaling pathway and increased the expression of LC3 and beclin-1 in MG63 cells. The present study demonstrated that ZnO NPs induced apoptosis and autophagy in MG63 cells through modifying apoptotic and autophagy-related proteins.

Design, synthesis, evaluation of new 3-acetylisoxazolines and their hybrid analogous as anticancer agents: In vitro and in silico analysis

3-Acetylisoxazolines were synthesized by the reaction of natural (R)-limonene and (R)-carvone with acetone in the presence of iron (III) nitrate. The reaction showed to be highly peri- and regioselective. Next, using a 1,3-dipolar cycloaddition reaction, the mono-3-acylisoxazolines derived from these monoterpenes were evaluated for their reactivity with nitrilimines. Only the enone of carvone-isoxazoline was regioselectively reactive, providing a new fused isoxazoline-carvone-pyrazolines. The structure of all the newly synthesized mono-cycloadducts (3 &5) and bis-cycloadducts (4 &7a–c) were fully identified based on their HRMS and NMR spectral data. They have also been screened for their cytotoxic activity against four human cancer cell lines: fibrosarcoma (HT-1080), lung carcinoma (A-549), and breast (MCF-7 and MDA-MB-231) cell lines. The obtained results showed that compound 4 was a potent cytotoxic agent against all selected cells. The possible mechanism of apoptosis induction by compound 4 was investigated using Annexin-V binding assay, caspase-3/7 activity and analysis cell cycle progression. The compound 4 induced the early apoptosis of both MCF-7 and MDA-MB-231 through caspase-3/7 activation, and the compound 4 have elicited S and G2/M phase arrest in MCF-7and MDA-MB-231 cancer cells, respectively. For further target investigations, a molecular docking study was employed and it showed that compound 4 has an inhibitory activity against Pim-1 protein kinase. Molecular dynamics study showed that compound 4/Pim-1 complex was stable during the simulation run at different time intervals. In-Silico ADMET predicted that compound 4 has good pharmacokinetic properties with high estimated oral bioavailability.

Plasma Jet Prepared Gold and Silver Nanoparticles to Induce Caspase-Independent Apoptosis in Digestive System Cancers

Alot of medical and industrial applications used the metal nanoparticles (NPs) with increase interest to be used as cancer therapy. The current work aimed to prepare AuNPs and AgNPs through the use of plasma jet and test their antitumor mechanism of apoptosis induction. The results indicating the face-centered cubic structures and crystalline nature of AuNPs and AgNPs. Also, the image of FESEM showed that the well dispersions regarding AuNPs and AgNPs, while the NP’s spherical shape with the particle size distributions which are considered to be close that estimated from the XRD. cytotoxicity have been assessed against the Normal embryonic cell line REF and the digestive system (HC , SK-GT-4) cell lines under a variety of the series dilute of the Ag and Au NPs (6.25, 12.5, 25, 50 and 100%), have been determined through a microtetrazolium (MTT) assay. The capacity of Ag and Au NPs to induce apoptosis to an infected cell has been studied by crystal violet stain to measure the percentage of induction of apoptosis. In cases where 100 μg\ml Au NP concentrations are 69.60 percent, the maximum cytotoxicity of the HC cell line was reported, while 100 μg\ml Au NP was 69.20% for the SKg cell line exposure. qRT-PCR in AuNPs and AgNPs treated of (HC and SKG) cell lines revealed a remarkable in the expression of BAX, BCL2 and AIF, Endo G (independent pathway).

Effect of 1,4-Napthoquinone Derivatives on Anti-proliferation and Apoptosis Induction in Skin and Lung Cancer Cells

Background: Cancer is a major public health concern around the world. Nowadays, standard therapy in combination with targeted therapy are being used for cancer treatment, but these therapeutics show side effects or unwanted symptoms and high cost. 1,4-Napthoquinone and their derivatives were used in cancer research for a long time with high efficiency than some cancer drug. In the present study, the effect of a novel 1,4-napthoquinone, DL667 and DL666 on apoptosis induction in malignant melanoma, A375 cells and lung cancer, A549 cells, respectively were studied. Objective: To investigate the effects of 1,4-napthoquinone derivatives, DL667 and DL66, on apoptosis induction in malignant melanoma, A375 and lung cancer, A549 cells, respectively. Materials and Methods: Cell growth inhibition was determined by MTT assay. Apoptosis induction was via chromatin condensation or apoptotic bodies determined by Hoechst staining. In addition, changes in mitochondrial membrane potential (ΔΨm) were done by JC-1 staining. Results: The results showed that DL667 inhibited cell growth in A375 with an IC50 at 11.2+0.419 μM in a concentration-dependent manner and DL666 inhibited cell growth of A549 cells at 200 μM. Hoechst staining assay revealed that both DL667 and DL666 could induce chromatin condensation and apoptotic bodies in A375 and A549 cells. In addition, the JC-1 staining showed that DL667 and DL666 decreased the ΔΨm, a marker event of early apoptosis via mitochondria, in A375 and A549 treated cells. Conclusion: DL667 and DL666 showed anti-proliferation and apoptosis induction in A375 and A549 cells, respectively. Moreover, DL667 and DL666 induced chromatin condensation, apoptotic bodies and decreased the ΔΨm, resulting in apoptosis cell death induction. Our results suggested that the decrease of ΔΨm may be further developed as a model for study in other cancer cell lines. However, the underlying mechanisms of apoptosis induction associated with signaling should be further studied. Keywords: 1,4-Napthoquinone; Apoptosis; Chromatin condensation; Apoptotic bodies; Mitochondrial membrane potential

Review of anticancer potentials and structure-activity relationships (SAR) of rhodanine derivatives.

Rhodanine has been recognized as a privileged scaffold in medicinal chemistry due to its well-known ability to demonstrate a broad range of biological activities. The possibility of structural diversification has contributed to the significance of rhodanine structure in effective drug discovery and design. Many studies have confirmed the potential of rhodanine-derived compounds in the treatment of different types of cancer through the apoptosis induction mechanism. Furthermore, most of the rhodanine derivatives exhibited remarkable anticancer activity in the micromolar range while causing negligible cytotoxicity to normal cells. This review critically describes the anticancer activity profile of reported rhodanine compounds and the structure-activity relationships (SAR) to highlight the value of rhodanine as the core structure for future cancer drug development as well as to assist the researchers in rational drug design.

Phytochemical and Pharmacology Effect of Calotropis gigantea as Anti-Cancer Therapy: Systematic Review

The high prevalence of cancer in the world makes many researchers look for alternative therapies that can be used to treat cancer. One of them is by using traditional plants, namely Calotropis gigantea R.Br. This is due to alkaloids, glycosides, and tannins in plants that function as anticancer. The purpose of this study was to dig deeper into information related to the phytochemistry and pharmacology effect of Calotropis gigantea as an anticancer therapy and can be used as a reference for the development of traditional medicines. The method used is PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses), with inclusion and exclusion criteria, 11 articles were selected for review. The results showed that Calotropis Gigantea contains Calotropin, Calotroposide A, oxypregnane oligoglycoside compounds, which inhibit cancer cell growth through the mechanism of apoptosis induction and ROS inhibition. From this systematic review, it can be recommended that the plant Calotropis gigantea can be further developed into standardized herbal medicine and phytopharmaceuticals.

Anti-Cancer Assessment of a Ramie (Boehmeria nivea L. Gaud.) Leaf Extract Using Mcf-7 Cell Line and a Yeast-Based Bioassay

Introduction: One strategy for molecular cancer therapy is to know the key mechanism of cytotoxic compounds that can kill cancer cells. Ramie (Boehmeria nivea L. Gaud.) leaves contain active compounds that have important effects on cancer chemoprevention. Objective: To obtain the active fraction of a Ramie leaf extract in inhibiting the proliferation of MCF-7 breast cancer cell lines and to determine the mechanism of apoptosis induction using MCF-7 and Saccharomyces cerevisiae strains 1140, 1353, and 1138. Method: Fractions were prepared using n-hexane, dichloromethane (CH2Cl2), ethyl acetate, and n-butanol as solvents. All fractions were tested qualitatively through phytochemical. The MTT-based cytotoxicity assay used MCF-7 (in vitro) to obtain the IC50 value, whereas the model system that targets the enzymatic (topoisomerase) used a yeast-based bioassay to obtain the IC12 value. Apoptotic induction of the active fraction in MCF-7 was performed using flow cytometry and qPCR (2-ΔΔCt method). Results: The phytochemical analysis indicated that the extract fraction consisted of alkaloids and steroids. The smallest IC50 value was obtained from the CH2Cl2 fraction as 3.79 g/mL, potentially act as an anticancer. A higher percentage of apoptosis than that of necrotizing cells and live cells was observed through flow cytometry. The CH2Cl2 fraction with an IC12 value < 8000 in strains 1140, 1353, and 1138 consistently showed the mechanism of apoptosis induction as topoisomerase I and II inhibitors. Also, another mechanism could be through the intrinsic pathway, indicated by the highest expression level in p53. Conclusions: The CH2Cl2 fraction of Ramie leaves can inhibits the proliferation of MCF-7 cells in the active and strong categories. The CH2Cl2 fraction induces apoptosis by increasing p53 gene expression and inhibiting topoisomerase I and II. Thus, it showed potential as an anticancer drug candidate.

Mitochondrial Fission Factor Is a Novel Interacting Protein of the Critical B Cell Survival Regulator TRAF3 in B Lymphocytes.

Proteins controlling mitochondrial fission have been recognized as essential regulators of mitochondrial functions, mitochondrial quality control and cell apoptosis. In the present study, we identified the critical B cell survival regulator TRAF3 as a novel binding partner of the key mitochondrial fission factor, MFF, in B lymphocytes. Elicited by our unexpected finding that the majority of cytoplasmic TRAF3 proteins were localized at the mitochondria in resting splenic B cells after ex vivo culture for 2 days, we found that TRAF3 specifically interacted with MFF as demonstrated by co-immunoprecipitation and GST pull-down assays. We further found that in the absence of stimulation, increased protein levels of mitochondrial TRAF3 were associated with altered mitochondrial morphology, decreased mitochondrial respiration, increased mitochondrial ROS production and membrane permeabilization, which eventually culminated in mitochondria-dependent apoptosis in resting B cells. Loss of TRAF3 had the opposite effects on the morphology and function of mitochondria as well as mitochondria-dependent apoptosis in resting B cells. Interestingly, co-expression of TRAF3 and MFF resulted in decreased phosphorylation and ubiquitination of MFF as well as decreased ubiquitination of TRAF3. Moreover, lentivirus-mediated overexpression of MFF restored mitochondria-dependent apoptosis in TRAF3-deficient malignant B cells. Taken together, our findings provide novel insights into the apoptosis-inducing mechanisms of TRAF3 in B cells: as a result of survival factor deprivation or under other types of stress, TRAF3 is mobilized to the mitochondria through its interaction with MFF, where it triggers mitochondria-dependent apoptosis. This new role of TRAF3 in controlling mitochondrial homeostasis might have key implications in TRAF3-mediated regulation of B cell transformation in different cellular contexts. Our findings also suggest that mitochondrial fission is an actionable therapeutic target in human B cell malignancies, including those with TRAF3 deletion or relevant mutations.

KP772 overcomes multiple drug resistance in malignant lymphoma and leukemia cells in vitro by inducing Bcl-2-independent apoptosis and upregulation of Harakiri

Despite high cure rates in pediatric patients with acute leukemia, development of resistance limits the efficacy of antileukemic therapy. Tris(1,10-phenanthroline)tris(thiocyanato-κN)lanthanum(III) (KP772) is an experimental antineoplastic agent to which multidrug-resistant cell models have shown hypersensitivity. Antiproliferative and apoptotic activities of KP772 were tested in leukemia, lymphoma and solid tumor cell lines as well as primary leukemia cells (isolated from the bone marrow of a child with acute myeloid leukemia (AML). The ability to overcome drug resistances was investigated in doxorubicin- and vincristine-resistant cell lines. Real-time PCR was used to gain insight into the mechanism of apoptosis induction. KP772 inhibited proliferation and induced apoptosis in various leukemia and lymphoma cell lines in a concentration-dependent manner (LC50 = 1–2.5 µM). Primary AML cells were also sensitive to KP772, whereas daunorubicin showed no significant effect. KP772 induces apoptosis independently of Bcl-2, Smac, and the CD95 receptor and is also effective in caspase 3-deficient MCF7 cells, indicating that apoptosis is partly triggered independently of caspase 3. mRNA expression profiling revealed an upregulation of the BH3-only Bcl-2 protein Harakiri in the course of KP772-induced apoptosis. Remarkably, KP772 overcame drug resistance to doxorubicin and vincristine in vitro, and the apoptotic effect in resistant cells was even superior to that in non-resistant parental cells. In combination with vincristine, doxorubicin and cytarabine, synergistic effects were observed in BJAB cells. The cytotoxic potency in vitro/ex vivo and the remarkable ability to overcome multidrug resistance propose KP772 as a promising candidate drug for antileukemic therapy, especially of drug-refractory malignancies.Graphic abstract

Luteolin combined with low-dose paclitaxel synergistically inhibits epithelial-mesenchymal transition and induces cell apoptosis on esophageal carcinoma in vitro and in vivo.

Although paclitaxel is a promising frontline chemotherapy agent for various malignancies, the clinical applications have been restricted by side effects, drug resistance, and cancer metastasis. The combination of paclitaxel and other agents could be the promising strategies against malignant tumor, which enhances the antitumor effect through synergistic effects, reduces required drug concentrations, and also suppresses tumorigenesis in multiple ways. In this study, we found that luteolin, a natural flavonoid compound, combined with low-dose paclitaxel synergistically regulated the proliferation, migration, epithelial-mesenchymal transition (EMT), and apoptosis of esophageal cancer cells in vitro, as well as synergistically inhibited tumor growth without obvious toxicity in vivo. The molecular mechanism of inhibiting cell migration and EMT processes may be related to the inhibition of SIRT1, and the mechanism of apoptosis induction is associated with the reactive oxygen species (ROS)/c-Jun N-terminal kinase (JNK) pathway-mediated activation of mitochondrial apoptotic pathway.

Pristimerin induces apoptosis and tumor inhibition of oral squamous cell carcinoma through activating ROS-dependent ER stress/Noxa pathway

BackgroundPristimerin (Pri), a natural quinone methide triterpenoid isolated from Celastraceae and Hippocrateaceae, exhibits potent antitumor activity against various cancers. However, the mechanism of apoptosis induction by Pri in oral squamous cell carcinoma (OSCC) and its anti-OSCC effect in vivo has not been widely studied. PurposeThis study aimed to investigate the anti-OSCC activities of Pri in vitro and in vivo and addressed the potential mechanisms of Pri-induced apoptosis. MethodsThe effects of Pri on OSCC cells were analyzed by cell viability, colony formation and flow cytometry assays. Western blotting and qRT-PCR assays were chosen to detect the expression of proteins and genes. The anti-OSCC efficacy of Pri in vivo was evaluated by CAL-27 xenografts. ResultsWe showed that Pri inhibited the proliferation of human OSCC cell lines. Additionally, Pri induced apoptosis by upregulating Noxa expression. Furthermore, Pri treatment triggered excessive endoplasmic reticulum (ER) stress activation and subsequently induced c-Jun N-terminal kinase (JNK) signaling. ROS scavengers and ER stress inhibitors significantly attenuated Pri-induced OSCC cell apoptosis. Finally, Pri suppressed tumor growth in CAL-27 xenografts, accompanied ER stress activation and cell apoptosis. ConclusionThese results reveal that Pri suppressed tumor growth and triggered cell apoptosis through ER stress activation in OSCC cells and xenografts, suggesting that Pri may serve as a therapeutic agent for OSCC.

Antioxidant, Anti-Inflammatory and Anticancer Activities of the Methanolic Extract of Thottea siliquosa: An In Vitro and In Silico Study.

Oxidative stress and inflammation are the predominant cause of chronic diseases, including multiple forms of cancers. Prevention of oxidative stress and inflammation is considered to be a target for preventing these disorders due to their significant roles in various degenerative diseases. Various natural products and plant extracts prevent the process of free radical- induced damages. The present study evaluated the biological properties of Thottea siliquosa, belonging to the family Aristolochiaceae, which is a traditionally used Ayurvedic plant. Antioxidant assays carried out were DPPH, FRAP, hydrogen peroxide scavenging, and hemolysis inhibition assay; nitric oxide and lipoxygenase inhibition assays were used for anti-inflammatory studies. Anticancer activity was evaluated using human endometrial and breast cancer cells by MTT assay. Bioactive compounds present in T. siliquosa were identified by LCMS and each was docked with various cancer targets, including EGFR, VEGFR, GST, COX2, and Lipooxygenase. The results of the present study showed antioxidant properties of the methanolic crude extract of T. siliquosa as DPPH radical scavenging (110.40 ± 4.5 μg/mL), FRAP capacity (41.1 ± 6.2), and peroxide scavenging (233.4 ± 14.2 μg/mL). Besides, anti-inflammatory properties were also evident in terms of nitric oxide radical scavenging (28.76± 3.9 μg/mL) and lipoxygenase inhibition (39.2 ± 3.2 μg/mL) assays. In silico analysis confirmed the inhibitory potential of the bioactive compounds of T. siliquosa against cancer drug targets such as EGFR, VEGFR, and inflammatory enzymes cyclooxygenase as well as lipooxygenase. Further, the anticancer activity of the extract has been identified against human endometrial and breast cancer cells. The possible mechanism of anticancer action of the extract is mediated through the apoptosis induction mechanism acting through increased caspase and APAF-1 expressions. The study thus concludes that T. siliquosa showed significant antioxidant, anti-inflammatory and anticancer properties. Further studies together with a bioassay-guided fractionation may identify possible bioactive compounds.

Effects of low-dose bufalin combined with hydroxycamptothecin on human castration-resistant prostate cancer xenografts in nude mice.

Prostate cancer is the most prevalent tumor found in men worldwide. Despite the efficiency of primary endocrine prostate cancer therapies, more efficient drugs are needed to tackle the most advanced and resistant forms of this condition. The present study investigated the antitumor effects of low-dose bufalin combined with hydroxycamptothecin on castration-resistant prostate cancer (CRPC) in mice, as well as the possible mechanisms of apoptosis induction. CRPC xenograft tumors were generated in mice and, subsequently, mice received appropriate doses of bufalin, hydroxycamptothecin or a combination of the two drugs. Tumors from each treatment group were removed, and the tumor volume, weight and inhibition rate of each group was determined. Hematoxylin and eosin staining was performed for pathological analysis and TUNEL staining was used to assess the level of apoptosis in the xenografts. Immunohistochemistry was used for the analysis of proliferating cell nuclear antigen expression and the expression of Bax, Bcl-XL, p53, programmed cell death 4 (PDCD4), phosphorylated (p)-AKT and glycogen synthase kinase (GSK)-3β was determined by western blotting. Treatment with bufalin significantly (P<0.05) reduced tumor volumes compared with the negative control group, reducing tumor volumes to lower levels when combined with hydroxycampothecin. The combination of bufalin (0.6 or 0.8 mg/kg) and hydroxycampothecin significantly (P<0.05) induced higher levels of cell apoptosis compared with the administration of bufalin or hydroxycampothecin alone. The combination of bufalin and hydroxycampothecin also increased the expression of apoptosis-related proteins Bax, p53, PDCD4 and GSK-3β, and decreased the expression of Bcl-XL and p-AKT compared with a single drug treatment. The present study suggested that the combination of bufalin and hydroxycampothecin improved the inhibitory effects of both drugs on CRPC tumors in vivo, potentially via the regulation of the PI3K/AKT/GSK-3β and p53-dependent apoptosis signaling pathways.