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Objective: To explore and analyze the efficacy of luteolin on the proliferation and apoptosis of cerebral glioma and its possible mechanism, providing a theoretical basis for luteolin in glioma treatment., Methods: The cell line of Human cerebral glioma U87 was utilized for our current research. The study group were added with 0, 20, 40, and 80 μmol/L luteolin, respectively. Luteolin's Inhibitory function in the proliferation of U87 cells was detected by CCK-8, the Transwell chamber test was used to measure cell migration and invasion, while flow cytometry was used to assess apoptosis and Western Blot to gauge the expression of JNK/STAT3 pathway proteins., Results: In comparison with the control group, the intervention of various doses of luteolin could effectively inhibit glioma cell proliferation, the inhibitory rate uplifted remarkably with an increase of dose as well as intervention time (95% CI. 92.160-107.494, P < .05), which presented a significant time and dose dependence. The apoptosis rate of the low-dose, medium-dose, and high-dose categories was higher than that of the comparison group after 2 days of luteolin intervention (P < .05), and the apoptosis rate appeared to increase with the increase in intervention dose (P < .05). After 2 days of luteolin intervention, there were significantly more migratory and invasive cells in 3 categories than that in the control group (P < .05), and the number increased as the luteolin intervention dose was raised (P < .05). Bax and Cyt-c expressions dropped after 2 days of luteolin treatment when compared with the control set (P < .05), and the expression of Bax and Cyt-c fell considerably with increasing luteolin dose. Bcl-2, Caspase-3 and PARP expressions were significantly elevated in comparison to the control group (P < .05), and the increase was more obvious with the rise of the luteolin dose., Conclusion: Luteolin has a good inhibiting function on the proliferation of glioma cells, inhibiting cellular invasion and migration and promoting the apoptosis of glioma cells and the expression of apoptosis-related proteins, which has laid a good foundation for the application of luteolin to treat glioma cells.

Background: Doxorubicin (Dox) is one of the most frequently prescribed anti-cancer drugs. However, clinical application with Dox is limited due to its potentially fatal cumulative cardiotoxicity. N- p -coumaroyl-4-aminobutan-1-ol (alk-A), an organic amide alkaloid and hippophamide (alk-B), a rare pyridoindole alkaloid were successfully obtained by purification and separation of seabuckthorn seed residue in our previous research. This study was undertaken to investigate the protective effect of alk-A and alk-B against Dox-induced embryonic rat cardiac cells (H9c2 cells) apoptosis., Methods: H9c2 cells were treated with Dox (2.5 µM) in the presence of alk-A and alk-B (10, 20, and 40 µM) and incubated for 24 h., Results: It was shown that pretreatment of the H9c2 cells with alk-A and alk-B significantly reduced Dox-induced apoptosis. Alk-A and alk-B both inhibited reactive oxygen species (ROS) production and suppressed cleaved-caspase-3 protein expression and the activation of JNK (Jun N-terminal kinases), as well as increasing ATP levels, favoring mitochondrial mitofusin protein expression, and relieving damage to mitochondrial DNA., Conclusions: These results suggest that alk-A and alk-B can inhibit Dox-induced apoptosis in H9C2 cardiac muscle cells via inhibition of cell apoptosis and improvement of mitochondrial function, while alk-B showed more protection. Alk-B could be a potential candidate agent for protecting against cardiotoxicity in Dox-exposed patients.

Digoxin has potential antitumor properties. This study investigated whether digoxin suppressed Burkitt's lymphoma (BL) cells. Raji and NAMALWA cells were exposed to digoxin, followed by assay of cell viability, apoptosis and cell cycle. Western blotting was used to analyze NF-κB activity. A xenograft model was established for therapeutic efficacy evaluation. Digoxin inhibited cell growth and resulted in apoptosis and cell cycle arrest (G0/G1 for Raji cells; G2/M for NAMALWA cells). Digoxin inhibited DNA synthesis and induced morphological apoptotic characteristics. Besides, digoxin inhibited NF-κB and TNF-α-stimulated NF-κB activity, and suppressed NF-κB initiating genes (Bcl-2, Bcl-xL, cyclin D1, and c-myc), however, increased p21 cip1 . Digoxin activated caspase-9/3. Furthermore, digoxin inhibited xenograft tumors growth and reduced Ki-67 and c-myc. Digoxin exerted antitumor effects on BL cells in vitro and in vivo might through regulating NF-κB and caspase pathway. These outcomes highlight the potential of digoxin as a therapeutic agent for BL.

The steroid Na+/K+-ATPase blocker ouabain has been shown to exhibit cytotoxic effects in various tumor cell systems. This study aimed to determine the effects of ouabain on Burkitt's lymphoma Raji cells. Ouabain treatment of Raji cells significantly inhibited cell proliferation in a dose-dependent manner and increased the morphological changes associated with apoptosis. Additionally, increased numbers of both early and late apoptotic cells were observed by annexin V-FITC/PI flow cytometry assay. Increased levels of caspase-3 and cleaved-caspase-3, higher Bax activity and decreased expression of the anti-apoptotic protein Bcl-2 were detected in ouabain-treated Raji cells. Vacuole accumulation was also observed in transmission electron microscope (TEM) images of ouabain-treated Raji cells, indicating that these cells were undergoing autophagy. Expression of the autophagy-related proteins LC3-II and Beclin-1 was upregulated in ouabain-treated Raji cells. These results suggest that ouabain may promote cell death in Raji cells by inducing pathways associated with apoptosis and autophagy. Our study also provides novel evidence that ouabain may be an effective agent for treating Burkitt's lymphoma., (Copyright © 2016. Published by Elsevier Masson SAS.)

Background: The aim of this study was to investigate the anticancer effect and related mechanisms of gambogic acid (GA), a traditional Chinese medicine, on human leukemia cell line K562, together with the effect on bone marrow mononuclear cells (MNCs)., Material and Methods: K562 cells and MNCs were treated with various concentrations and treatment times of GA. Inhibitory rate was detected by use of the Cell Counting Kit-8 (CCK-8) assay. Apoptosis was analyzed by morphological detection, Annexin-V/PI doubling staining, and TUNEL assays. The expression changes of pivotal proteins were evaluated by Western blotting., Results: GA not only suppressed cell proliferation, but also induced apoptosis of K562 cells in a dose-dependent manner. While it did not significantly inhibit cell proliferation of MNCs, it did induce apoptosis in a dose-dependent manner. CCK-8 assay revealed that the proliferation of K562 cells was significantly inhibited when the concentration of GA was more than 0.5 μM. Morphological detection showed the nuclei became denser and more intense orange in K562 cells after GA treatment compared with the untreated group. The expression levels of BCL-2, nuclear factor-κB (NF-κB), c-myc, phosphatidylinositol3-kinase (PI3K), and phosphorylation of serine-threonine kinase (p-AKT) were down-regulated by GA., Conclusions: GA significantly suppressed the proliferation of K562 cells, but has less effect on MNCs. The inhibition of K562 cells proliferation and apoptosis induced by GA might be related to the down-regulation of BCL-2, NF-κB, c-myc, PI3K, and p-AKT.

This study was aimed to detect the effects of gambogic acid (GA) on the growth of chronic myelogenous leukemia (CML) K562 cells. Our results showed that GA induced the accumulation of autophagic vacuoles and up-regulation of two autophagy-related proteins (Beclin 1 and LC3). GA also induced down-regulation of mRNA levels of BCR-ABL fusion gene and SQSTM1/sequestosome 1 (p62) protein levels. After treatment by chloroquine (CQ) and pan caspase inhibitor Z-VAD-FMK (PC), both GA-induced autophagy and apoptosis were inhibited. Our study demonstrates that GA may induce cell death through autophagy and apoptosis pathways in CML K562 cells. A cross-talk mechanism exists between GA-induced autophagy and apoptosis. However, the mechanism of GA for inducing autophagy and apoptosis need further clarification.

Celastrol is an active compound extracted from the root bark of the traditional Chinese medicine Tripterygium wilfordii Hook F. To investigate the effect of celastrol on human multiple myeloma cell cycle arrest and apoptosis and explore its molecular mechanism of action. The activity of celastrol on LP-1 cell proliferation was detected by WST-8 assay. The celastrol-induced cell cycle arrest was analyzed by flow cytometry after propidium iodide staining. Nuclear translocation of the nuclear factor kappa B (NF-κB) was observed by fluorescence microscope. Celastrol inhibited cell proliferation of LP-1 myeloma cell in a dose-dependent manner with IC50 values of 0.8817 µM, which was mediated through G1 cell cycle arrest and p27 induction. Celastrol induced apoptosis in LP-1 and RPMI 8226 myeloma cells in a time and dose dependent manner, and it involved Caspase-3 activation and NF-κB pathway. Celastrol down-modulated antiapoptotic proteins including Bcl-2 and survivin expression. The expression of NF-κB and IKKa were decreased after celastrol treatment. Celastrol effectively blocked the nuclear translocation of the p65 subunit and induced human multiple myeloma cell cycle arrest and apoptosis by p27 upregulation and NF-kB modulation. It has been demonstrated that the effect of celastrol on NF-kB was HO-1-independent by using zinc protoporphyrin-9 (ZnPPIX), a selective heme oxygenase inhibitor. From the results, it could be inferred that celastrol may be used as a NF-kB inhibitor to inhibit myeloma cell proliferation.

The aim of this study was to investigate the apoptosis-inducing effect of gambogic acid (GA) on Jurkat cells and its underlying signaling pathway. Apoptosis induced by GA and some inhibitors was assayed by Annexin V/PI doubling staining. The levels of caspase 3, caspase 8 and caspase 9 activated in living Jurkat cells were measured by flow cytometry. The expressions of caspase 3, caspase 9, p-JNK and P38 were detected by Western blot. The results showed that GA induced apoptosis of Jurkat cells in a dose-dependent manner. The positive cell number of activated caspase 3, caspase 8, caspase 9 and the levels of activated caspase 3, caspase 9, p-JNK, P38 increased after Jurkat cells were treated with GA. ROS, CaMKII, caspase 3, caspase 9, MAPKK, JNK1/2 and P38 inhibitors had some significant effect on GA-induced apoptosis. ROS, CaMKII, MAPKK, JNK1/2 and P38 inhibitors decreased the levels of activated caspase 3, caspase 9 by GA.ROS, CaMKII, MAPKK, JNK1/2 inhibitors decreased the levels of p-JNK by GA. ROS, CaMKII, MAPKK, P38 inhibitors decreased the levels of P38 by GA. It is concluded that GA induced apoptosis of Jurkat cells by activated caspases through activating of ROS-CaMKII-MAPKK-JNK/P38 pathway.

This study was aimed to investigate the apoptosis-inducing effect of gambogic acid (GA) on K562 cell line and its mechanism. The K562 cells were treated with GA at different concentrations and times, the inhibition rates were detected by MTT assay. Apoptosis induced by GA was assayed by Annexin-V/PI doubling staining. The influence of GA on cell cycle was studied by propidium iodide method. The mitochondrial membrane potential was measured by JC assay. The levels of caspase 3, caspase 8 and caspase 9 activated by fluorescein in living K562 cells were measured by caspGLOW(TM) fluorescein staining kit. The results showed that after incubation with GA, K562 cell proliferation was dramatically inhibited in concentration- and time-dependent manners. K562/A02 cells need higher GA concentration (> 2 microg/ml) to show antiproliferative effect, compared with that of K562 cells (> 0.5 microg/ml). Apoptosis could be induced by GA but the influence on cell cycle was not significant. GA could decrease the mitochondrial membrane potential and increase the activated caspase 3, caspase 8, caspase 9 positive cell levels by 2.19%, -1.95%, 34.01% in 24 hr and 60.4%, 71.3%, 77.7% in 48 hr respectively. It is concluded that the GA can significantly inhibit the proliferation of K562 cells without influence on cell cycles. The GA triggers K562 cell apoptosis through both intrinsic and extrinsic pathways.

This study was aimed to investigate the change of expression and activity of protein phosphatases type 2A (PP2A) during the apoptosis of NB4 and MR2 cells induced by Arsenic trioxide (ATO). NB4 and MR2 cells were incubated with Okadaic acid (OKA) (0.5 nmol/L), ATO (0.5 - 2.0 micromol/L), and the combination of OKA and ATO at the same doses as in the single-agent treatment respectively. Then the proliferation of NB4 and MR2 cells was determined by MTT assay, the morphologic changes of cells were evaluated by Wright's staining, the apoptosis rates were detected by flow cytometry. At last, the activities of PP2A were evaluated by the serine/threonine phosphatase assay system, and the levels of PP2A subunits were detected by Western blot analysis. The results showed that ATO inhibited proliferation of NB4 and MR2 cells, and the inhibition rates of ATO on the two cells significantly increased after the addition of OKA. OKA could augment the apoptosis of NB4 and MR2 cells induced by ATO. During the apoptosis of NB4 and MR2 cells, the activity of PP2A decreased with increasing concentration of ATO, and OKA augmented the inhibitory effect of ATO on the activity. The level of PP2A structural subunit (PP2A-A) decreased during ATO-induced apoptosis of NB4 and MR2 cells, that expressions of B and C subunits of PP2A were relatively unaltered. It is concluded that the activity of PP2A decreases with increasing concentration of ATO during the apoptosis of NB4 and MR2 cells, and the decrease of the activity of PP2A maybe is related to the repression of expression of PP2A -A subunit; the inhibition of the activity of PP2A can promote the ATO induced apoptosis of NB4 and MRL cells.

Arsenic trioxide (ATO) is known to have concentration-dependent dual effects on acute promyelocytic leukemia (APL) cells, preferentially inducing apoptosis at relatively high concentrations and promoting partial differentiation at low concentrations. Protein phosphatase 2A (PP2A) has been demonstrated to take part in the differentiation and apoptosis of malignant hematological cells induced by commonly used medicines, such as all-transretinoic acid (ATRA), interferon, arsenic sulfide, etc. However, there are almost no data on the role PP2A plays in ATO-induced APL cell differentiation/apoptosis. In this report, our goal was to show that ATO inhibited the proliferation and induced the apoptosis and differentiation of neuroblastoma NB4 cells. Okadaic acid (OKA), a specific inhibitor of protein phosphatase activity, markedly increased these effects of ATO on cells. To further elucidate the regulation of PP2A during ATO-induced differentiation/apoptosis of NB4 cells, we measured the phosphatase activity and protein expression of PP2A. The activity of PP2A in NB4 cells decreased with increasing concentration of ATO. This decrease of PP2A activity appeared to parallel phenotypic and functional changes of NB4 cells. Western blot analysis showed that the levels of the PP2A structural subunit PP2A-A decreased during the course of ATO-induced differentiation/apoptosis, whereas the expression of the B and C subunits of PP2A was relatively unaltered. In conclusion, the decrease of PP2A activity may be involved in ATO-induced apoptosis and differentiation of APL cells, and this decrease is predicted to be related to the repression of PP2A-A subunit expression., (Copyright 2008 Prous Science, S.A.U. or its licensors. All rights reserved.)

Purpose: Adhesion between calcium oxalate crystals and renal tubular epithelial cells is a vital cause of renal stone formation; however, the drugs that inhibit crystal adhesion and the mechanism of inhibition have yet to be explored. Methods: The cell injury model was constructed using nano-COM crystals, and changes in oxidative stress levels, endoplasmic reticulum (ER) stress levels, downstream p38 MAPK protein expression, apoptosis, adhesion protein osteopontin expression, and cell–crystal adhesion were examined in the presence of Laminarin polysaccharide (DLP) and sulfated DLP (SDLP) under protected and unprotected conditions. Results: Both DLP and SDLP inhibited nano-COM damage to human kidney proximal tubular epithelial cell (HK-2), increased cell viability, decreased ROS levels, reduced the opening of mitochondrial membrane permeability transition pore, markedly reduced ER Ca2+ ion concentration and adhesion molecule OPN expression, down-regulated the expression of ER stress signature proteins including CHOP, Caspase 12, and p38 MAPK, and decreased the apoptosis rate of cells. SDLP has a better protective effect on cells than DLP. Conclusions: SDLP protects HK-2 cells from nano-COM crystal-induced apoptosis by reducing oxidative and ER stress levels and their downstream factors, thereby reducing crystal–cell adhesion interactions and the risks of kidney stone formation. [ABSTRACT FROM AUTHOR]

Digoxin has potential antitumor properties. This study investigated whether digoxin suppressed Burkitt's lymphoma (BL) cells. Raji and NAMALWA cells were exposed to digoxin, followed by assay of cell viability, apoptosis and cell cycle. Western blotting was used to analyze NF-κB activity. A xenograft model was established for therapeutic efficacy evaluation. Digoxin inhibited cell growth and resulted in apoptosis and cell cycle arrest (G0/G1 for Raji cells; G2/M for NAMALWA cells). Digoxin inhibited DNA synthesis and induced morphological apoptotic characteristics. Besides, digoxin inhibited NF-κB and TNF-α-stimulated NF-κB activity, and suppressed NF-κB initiating genes (Bcl-2, Bcl-xL, cyclin D1, and c-myc), however, increased p21cip1. Digoxin activated caspase-9/3. Furthermore, digoxin inhibited xenograft tumors growth and reduced Ki-67 and c-myc. Digoxin exerted antitumor effects on BL cells in vitro and in vivo might through regulating NF-κB and caspase pathway. These outcomes highlight the potential of digoxin as a therapeutic agent for BL. [ABSTRACT FROM AUTHOR]

Burkitt's lymphoma is a highly proliferative B-cell malignancy characterized by MYC oncogene translocation. Intensive short-cycle chemotherapy could effectively improve the outcome of this disease. However, drug resistance limits the treatment of refractory/relapsed disease. Thus, we constructed and investigated a novel cadmium-tellurium quantum dot conjugated with doxorubicin and gambogic acid (DOX/GA-CdTe QDs) for cancer cell combined treatment in Raji, a Burkitt's lymphoma cell line. Results showed that DOX/GA-CdTe QDs could significantly improve anti-tumor effects compared with drugs alone in the Raji cell line. Flow cytometry, transmission electron micrographs and overexpression of Beclin1 and LC3 II/I showed that apoptosis and autophagy were involved in the process. However, DOX/GA-CdTe QDs did not cause cell cycle arrest, whereas DOX alone or combined with GA could cause apparent G2/M phase arrest. Hence, the novel DOX/GA-CdTe QDs offer a promising approach of drug delivery into cancer cells. A novel cadmium-tellurium quantum dot conjugated with doxorubicin and gambogic acid (DOX/GA-CdTe QDs) was constructed for Burkitt's lymphoma combined treatment. DOX/GA-CdTe QDs could significantly enhance anti-tumor effects as compared to drugs alone, through improving the apoptosis and autophagy of the cancer cells. [ABSTRACT FROM AUTHOR]

Since arsenic trioxide (As3+) has been successfully used in the treatment of acute promyelocytic leukemia (APL), its adverse effects on patients have been problematic and required a solution. Considering the good therapeutic potency and low toxicity of tetraarsenictetrasulfide (As4S4) in the treatment of APL, we investigated the effects of combining As4S4 and As3+ on the apoptosis and differentiation of NB4 and primary APL cells. As4S4, acting similarly to As3+, arrested the G1/S transition, induced the accumulation of cellular reactive oxygen species, and promoted apoptosis. Additionally, low concentrations of As4S4 (0.1–0.4 μM) induced differentiation of NB4 and primary APL cells. Compared with the As4S4- or As3+-treated groups, the combination of As4S4 and As3+ obviously promoted apoptosis and differentiation of NB4 and primary APL cells. Mechanistic studies suggested that As4S4 acted synergistically with As3+ to down-regulate Bcl-2 and nuclear factor-κB expression, up-regulate Bax and p53 expression, and induce activation of caspase-12 and caspase-3. Moreover, the combination of low concentrations of As4S4 and As3+ enhanced degradation of the promyelocytic leukemia-retinoic acid receptor α oncoprotein. In summary, As4S4 and As3+ synergistically induce the apoptosis and differentiation of NB4 and primary APL cells. [ABSTRACT FROM AUTHOR]