In vitro anticancer activity of Spondias pinnata bark on human lung and breast carcinoma

Spondias pinnata, a commonly distributed tree in India, previously proven for various pharmacological properties and also reported for efficient anti-oxidant, free radical scavenging and iron chelating activity, continuing this, the present study is aimed to investigate the role of 70 % methanolic extract of S. pinnata bark (SPME) in promoting apoptosis in human lung adenocarcinoma cell line (A549) and human breast adenocarcinoma cell line (MCF-7). These two malignant cell lines and a normal cell line were treated with increasing concentrations of SPME and cell viability is calculated. SPME showed significant cytotoxicity to both A549 and MCF-7 cells with an IC₅₀ value of 147.84 ± 3.74 and 149.34 ± 13.30 μg/ml, respectively, whereas, comparatively no cytotoxicity was found in normal human lung fibroblast cell line (WI-38): IC₅₀ 932.38 ± 84.44 μg/ml. Flow cytometric analysis and confocal microscopic studies confirmed that SPME is able to induce apoptosis in both malignant cell lines. Furthermore, immunoblot result proposed the pathway of apoptosis induction by increasing Bax/Bcl-2 ratio in both cell types, which results in the activation of the caspase-cascade and ultimately leads to the cleavage of Poly adeno ribose polymerase. For the first time this study proved the anticancer potential of SPME against human lung and breast cancer by inducing apoptosis through the modulation of Bcl-2 family proteins. This might take S. pinnata in light to investigate it for further development as therapeutic anticancer source.     

Sulfamic acid promoted one-pot synthesis of phenanthrene fused-dihydrodibenzo-quinolinones: Anticancer activity,tubulin polymerization inhibition and apoptosis inducing studies

A facile one-pot method for the synthesis of new phenanthrene fused-dihydrodibenzo-quinolinone derivatives has been successfully accomplished by employing sulfamic acid as catalyst. These new compounds were evaluated for their in vitro cytotoxic potential against human lung (A549), prostate (PC-3 and DU145), breast (MCF-7) and colon (HT-29 and HCT-116) cancer cell lines. Among all the tested compounds, one of the derivatives 8p showed good anti-proliferative activity against A549 lung cancer cell line with an IC₅₀ of 3.17?±?0.52?µM. Flow cytometric analyses revealed that compound 8p arrested both Sub G1 and G2/M phases of cell cycle in a dose dependent manner. The compound 8p also displayed significant inhibition of tubulin polymerization and disruption of microtubule network (IC₅₀ of 5.15?±?0.15?µM). Molecular docking studies revealed that compound 8p efficiently interacted with critical amino acid Cys241 of the α/β-tubulin by a hydrogen bond (SH…O?=?2.4?Å). Further, the effect of 8p on cell viability was also studied by AO/EB, DCFDA and DAPI staining. The apoptotic characteristic features revealed that 8p inhibited cell proliferation effectively through apoptosis by inducing the ROS generation. Analysis of mitochondrial membrane potential through JC-1 staining and annexin V binding assay indicated the extent of apoptosis in A549 cancer cells.     

Homocysteine modulates the proteolytic potential of human arterial smooth muscle cells through a reactive oxygen species dependant mechanism

Suberoyl bishydroxamic acid (SBHA) as a histone deacetylase (HDAC) inhibitor has various cellular effects such as cell growth and apoptosis. In the present study, we evaluated the effects of SBHA on the growth and death of A549 lung cancer cells. SBHA inhibited the growth of A549 cells with an IC₅₀ of approximately 50 μM at 72 h in a dose-dependent manner. DNA flow cytometric analysis indicated that SBHA induced a G2/M phase arrest of the cell cycle. This agent also induced apoptosis, as evidenced by sub-G1 cells and annexin V-FITC staining cells. SBHA-induced apoptosis was accompanied by the loss of mitochondrial membrane potential (MMP; ΔΨ_m), Bcl-2 decrease, Bax increase, and the activation of caspase-3. All of the tested caspase inhibitors significantly rescued some cells from SBHA-induced A549 cell death. However, none of the caspase inhibitors prevented the loss of MMP (ΔΨ_m) induced by SBHA. Intracellular reactive oxygen species (ROS) levels including O ₂ ^?? were increased in 50 μM SBHA-treated A549 cells. None of the caspase inhibitors attenuated ROS levels in these cells. SBHA also elevated the number of glutathione (GSH)-depleted cells in A549 cells, which was reduced by treatment with caspase inhibitors. In conclusion, this is the first report that SBHA inhibited the growth of A549 lung cancer cells via caspase-dependent apoptosis, which was related to GSH depletion rather than changes in ROS level.     

Seleno-short-chain chitosan induces apoptosis in human non-small-cell lung cancer A549 cells through ROS-mediated mitochondrial pathway

Seleno-short-chain chitosan (SSCC) is a synthesized chitosan derivative. In this study, antitumor activity and underlying mechanism of SSCC on human non-small-cell lung cancer A549 cells were investigated in vitro. The MTT assay showed that SSCC could inhibit cell viability in a dose- and time-dependent manner, and 200 μg/ml SSCC exhibited significantly toxic effects on A549 cells. The cell cycle assay showed that SSCC triggered S phase cell cycle arrest in a dose- and time-dependent manner, which was related to a downregulation of S phase associated cyclin A. The DAPI staining and Annexin V-FITC/PI double staining identified that the SSCC could induce A549 cells apoptosis. Further studies found that SSCC led to the generation of reactive oxygen species (ROS) and the disruption of mitochondrial membrane potential (MMP) by DCFH-DA and Rhodamin 123 staining, respectively. Meanwhile, free radical scavengers N-acetyl-l-cysteine (NAC) pretreatment confirmed that SSCC-induced A549 cells apoptosis was associated with ROS generation. Furthermore, real-time PCR and western blot assay showed that SSCC up-regulated Bax and down-regulated Bcl-2, subsequently incited the release of cytochrome c from mitochondria to cytoplasm, activated the increase of cleaved-caspase 3 and finally induced A549 cells apoptosis in vitro. In general, the present study demonstrated that SSCC induced A549 cells apoptosis via ROS-mediated mitochondrial apoptosis pathway.     

Recombinant Balsamin induces apoptosis in liver and breast cancer cells via cell cycle arrest and regulation of apoptotic pathways

Recombinant balsamin (rBalsamin), a type I ribosome inactivating protein classified as RNA N-glycosidase, is known to possess antibacterial and DNase like activity. However, its anticancer properties have not yet been examined. In this study, we aimed to investigate the potential cytotoxicity of rBalsamin on hepatocellular (HepG2 and H4IIE) and breast (MCF-7 and BT549) carcinoma cells and the related mechanism. rBalsamin arrested cell cycle at G or S phase and increased the level of caspase-3/8. The expression of Bax, Bid, Bad and p53 increased and that of Bcl-2 and BCL-xl decreased in liver and breast cancer cells with rBalsamin treatment. We found that rBalsamin inhibited cell viability of liver and breast cancer cells in a concentration and time dependent manner with IC₅₀ ranging between 18.92 to > 200 μg/mL. These findings suggest that rBalsamin induced apoptosis in liver and breast cancer cells via death receptor and mitochondrial associated apoptotic pathways, could prove beneficial in the field of cancer therapeutics, highlighting its potential as a functional food ingredient.     

Synthesis of substituted biphenyl methylene indolinones as apoptosis inducers and tubulin polymerization inhibitors

A new series of biphenyl methylene indolinones has been designed, synthesized and evaluated for their in vitro antiproliferative activity against various cancer cell lines like DU-145 (prostate cancer cell line), 4T1 (mouse breast cancer cell line), MDA-MB-231 (human breast cancer cell line), BT-549 (human breast cancer cell line), T24 (human urinary bladder carcinoma cell line), and HeLa (cervical cancer cell line). Among the series, compound 10e showed potent in vitro cytotoxic activity against HeLa and DU-145 cancer cell lines with IC₅₀ value of 1.74 ± 0.69 µM and 1.68 ± 1.06 µM respectively. To understand the underlying mechanism of most potent cytotoxic compound 10e, various mechanistic studies were carried out on DU-145 cell lines. Cell cycle analysis results revealed that these conjugates affect both G0/G1 and G2/M phase of the cycle, tubulin binding assay resulted that compound 10e interrupting microtubule network formation by inhibiting tubulin polymerization with IC₅₀ value of 4.96 ± 0.05 μM. Moreover, molecular docking of 10e on colchicine binding site of the tubulin explains the interaction of 10e with tubulin. Clonogenic assay indicated inhibition of colony formation by compound 10e in a dose dependent manner. In addition, morphological changes were clearly observed by AO/EB and DAPI staining studies. Moreover, ROS detection using DCFDA, JC-1, and annexin V-FITC assays demonstrated the significant apoptosis induction by 10e.     

In vitro anti-proliferative effects of Zuojinwan on eight kinds of human cancer cell lines

Zuojinwan (ZJW), a famous Chinese medicinal formula, contains two medicinal herbs Coptis chinese Frach and Evodia rutaecarpa (Juss.) Benth in the ratio of 6: 1. The inhibitory effects of ZJW on eight kinds of human cancer cell lines including SMMC-7721, BEL-7402, BEL-7404, HepG2, A549, NCI-H446, NCI-H460 and HCT- 116 cells were evaluated, and the possible mechanism was investigated. The growths of the eight kinds of cancer cells were inhibited by ZJW assessed through MTT assay. Flow cytometry assay revealed a sub-G1 peak with reduced DNA content was formed. The cell cycle was arrested in the G0/G1 phase in ZJW-treated SMMC-7721 and HepG2 cells, and in the S phase for NCI-H460 cells. Significant DNA damage was produced by ZJW assessed with single-cell gel electrophoresis assay. Morphological changes were also observed. Caspase-3 and -9 activities were increased following ZJW treatment. Western blot analysis showed that Bax and Bak protein levels were increased after ZJW treatment, while Bcl-2 and Bcl-xl protein levels were decreased. Our results suggest that ZJW has significant anti-cancer activities due to induction of mitochondria- dependent apoptosis pathway. Therefore, ZJW has the potential to be a novel chemotherapy drug to treat hepatoma, lung cancer and colon cancer by suppressing tumor growth.     

PNAS-4, an Early DNA Damage Response Gene,Induces S Phase Arrest and Apoptosis by Activating Checkpoint Kinases in Lung Cancer Cells

PNAS-4, a novel pro-apoptotic gene, was activated during the early response to DNA damage. Our previous study has shown that PNAS-4 induces S phase arrest and apoptosis when overexpressed in A549 lung cancer cells. However, the underlying action mechanism remains far from clear. In this work, we found that PNAS-4 expression in lung tumor tissues is significantly lower than that in adjacent lung tissues; its expression is significantly increased in A549 cells after exposure to cisplatin, methyl methane sulfonate, and mitomycin; and its overexpression induces S phase arrest and apoptosis in A549 (p53 WT), NCI-H460 (p53 WT), H526 (p53 mutation), and Calu-1 (p53^−/−) lung cancer cells, leading to proliferation inhibition irrespective of their p53 status. The S phase arrest is associated with up-regulation of p21^Waf1/Cip1 and inhibition of the Cdc25A-CDK2-cyclin E/A pathway. Up-regulation of p21^Waf1/Cip1 is p53-independent and correlates with activation of ERK. We further showed that the intra-S phase checkpoint, which occurs via DNA-dependent protein kinase-mediated activation of Chk1 and Chk2, is involved in the S phase arrest and apoptosis. Gene silencing of Chk1/2 rescues, whereas that of ATM or ATR does not affect, S phase arrest and apoptosis. Furthermore, human PNAS-4 induces DNA breaks in comet assays and γ-H2AX staining. Intriguingly, caspase-dependent cleavage of Chk1 has an additional role in enhancing apoptosis. Taken together, our findings suggest a novel mechanism by which elevated PNAS-4 first causes DNA-dependent protein kinase-mediated Chk1/2 activation and then results in inhibition of the Cdc25A-CDK2-cyclin E/A pathway, ultimately causing S phase arrest and apoptosis in lung cancer cells.     

Pyrogallol inhibits the growth of human pulmonary adenocarcinoma A549 cells by arresting cell cycle and triggering apoptosis

Pyrogallol (PG) is a polyphenol compound and has been known to be an O generator. We evaluated the effects of PG on the growth of human pulmonary A549 cells in relation to the cell cycle and apoptosis. Treatment with 50 or 100 μM PG significantly inhibited the cell growth of A549 for 72 h. DNA flow cytometric analysis indicated that PG slightly induced a G1 phase arrest of the cell cycle at 24 or 48 h, but did not induce the specific cell cycle arrest at 72 h. Intracellular GSH depletion was observed in PG‐treated cells. PG induced apoptosis in A549 cells, as evidenced by sub‐G1 cells, annexin V staining cells, and the loss of mitochondrial membrane potential (Δ Ψ_m). The intracellular ROS (reactive oxygen species) level including O increased in PG‐treated A549 cells at 24 and 48 h, and persisted at 72 h. The changes in GSH as well as ROS levels by PG affected the cell viability in A549 cells. In conclusion, PG inhibited the growth of human pulmonary A549 cells by inducing cell cycle arrest as well as triggering apoptosis. © 2009 Wiley Periodicals, Inc. J Biochem Mol Toxicol 23:36–42, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/jbt.20263     

Synthesis,anticancer activity and molecular docking studies on 1,2-diarylbenzimidazole analogues as anti-tubulin agents

Twenty-four 1,2-diarylbenzimidazole derivatives were designed, synthesized and biologically evaluated. It turned out that most of them were potential anticancer drugs. Among them, compound c24 showed the highest anti-tumor activity (GI₅₀ = 0.71–2.41 μM against HeLa, HepG2, A549 and MCF-7 cells), and low toxicity to normal cells (CC₅₀ > 100 μM against L02 cells). In the microtubule binding assay, c24 showed the most potent inhibition of microtubule polymerization (IC₅₀ = 8.47 μM). The binding ability of compound c24 to tubulin crystal was verified by molecular docking simulation experiment. Further studies on HepG2 and HeLa cells showed that compound c24 could cause mitotic arrest of tumor cells to G2/M phase then inducing apoptosis. To sum up, compound c24 is a promising microtubule assembly inhibitor.     

Development of a capillary electrophoresis method for analyzing adenosine deaminase and purine nucleoside phosphorylase and its application in inhibitor screening

A novel capillary electrophoresis (CE) method was developed for simultaneous analysis of adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP) in red blood cells (RBCs). The developed method considered and took advantage of the natural conversion from the ADA product, inosine to hypoxanthine. The transformation ratio was introduced for ADA and PNP analysis to obtain more reliable results. After optimizing the enzymatic incubation and electrophoresis separation conditions, the determined activities of ADA and PNP in 12 human RBCs were 0.237–0.833 U/ml and 9.013–10.453 U/ml packed cells, respectively. The analysis of ADA in mice RBCs indicated that there was an apparent activity difference between healthy and hepatoma mice. In addition, the proposed method was also successfully applied in the inhibitor screening from nine traditional Chinese medicines, and data showed that ADA activities were strongly inhibited by Rhizoma Chuanxiong and Angelica sinensis. The inhibition effect of Angelica sinensis on ADA is first reported here and could also inhibit PNP activity.     

Antimetastatic effects of Phyllanthus on human lung (A549) and breast (MCF-7) cancer cell lines

Background

Current chemotherapeutic drugs kill cancer cells mainly by inducing apoptosis. However, they become ineffective once cancer cell has the ability to metastasize, hence the poor prognosis and high mortality rate. Therefore, the purpose of this study was to evaluate the antimetastatic potential of Phyllanthus (P. niruri, P. urinaria, P. watsonii, and P. amarus) on lung and breast carcinoma cells.

Methodology/Principal Findings

Cytotoxicity of Phyllanthus plant extracts were first screened using the MTS reduction assay. They were shown to inhibit MCF-7 (breast carcinoma) and A549 (lung carcinoma) cells growth with IC₅₀ values ranging from 50–180 µg/ml and 65–470 µg/ml for methanolic and aqueous extracts respectively. In comparison, they have lower toxicity on normal cells with the cell viability percentage remaining above 50% when treated up to 1000 µg/ml for both extracts. After determining the non-toxic effective dose, several antimetastasis assays were carried out and Phyllanthus extracts were shown to effectively reduce invasion, migration, and adhesion of both MCF-7 and A549 cells in a dose-dependent manner, at concentrations ranging from 20–200 µg/ml for methanolic extracts and 50–500 µg/ml for aqueous extracts. This was followed by an evaluation of the possible modes of cell death that occurred along with the antimetastatic activity. Phyllanthus was shown to be capable of inducing apoptosis in conjunction with its antimetastastic action, with more than three fold increase of caspases-3 and -7, the presence of DNA-fragmentation and TUNEL-positive cells. The ability of Phyllanthus to exert antimetastatic activities is mostly associated to the presence of polyphenol compounds in its extracts.

Conclusions/Significance

The presence of polyphenol compounds in the Phyllanthus plant is critically important in the inhibition of the invasion, migration, and adhesion of cancer cells, along with the involvement of apoptosis induction. Hence, Phyllanthus could be a valuable candidate in the treatment of metastatic cancers.     

姜黄素类似物EF24诱导A549细胞自噬及凋亡关系的研究

从细胞自噬及凋亡关系角度探讨姜黄素类似物EF24对人肺腺癌细胞（A549）的杀伤机理。选用不同浓度的EF24对体外培养的A549处理,采用MTT方法检查细胞存活率,吖啶橙染色观察细胞形态,蛋白质免疫印迹（Western blot）方法检测与细胞自噬及凋亡相关蛋白的表达及对AMPK-mTOR-S6K信号通路的影响。结果显示,EF24作用24 h的IC50为8.5μmol/L,对A549细胞生长抑制作用优于姜黄素,而接近顺铂。自噬及凋亡蛋白检测显示,在4μmol/L、8μmol/L时A549细胞以自噬为主,在16μmol/L时以凋亡为主;加入100 nmol/L自噬抑制剂渥曼青霉素（wortmannin）后,细胞存活率同比升高。同时还发现,随着EF24浓度的增加,细胞内AMPK-Thr172磷酸化水平上升,mTOR-Ser2481、S6K-Thr389磷酸化水平的下调。由此可见,EF24可通过AMPK的激活下调mTOR-S6K途径抑制细胞生长,在EF24浓度4~8μmol/L范围内,自噬对凋亡起到促进作用。     

Cytotoxic clerodane diterpenoids from the leaves of Casearia kurzii

A phytochemical investigation to obtain bioactive substances as lead compounds or agents for cancer led to the obtainment of six new clerodane diterpenoids, designated as kurzipenes A–F (1–6), from the leaves of Casearia kurzii. Their structures were elucidated on the basis of NMR spectroscopic data analysis and the absolute configurations were confirmed by the time-dependent density functional theory (TDDFT) electronic circular dichroism (ECD) calculations. The cytotoxic activities of compounds 1–6 were evaluated against human lung cancer A549 cell line, human cervical cancer Hela cell line, and human hepatocellular carcinoma HepG2 cell line. Most diterpenoids showed potent cytotoxicities against the three selected cancer cell lines. The preliminary mechanism studies revealed that the most active compound 2, with an IC₅₀ value of 5.3 μM against Hela cells, induced apoptosis and arrested the Hela cell cycle at the G0/G1 stage to exert cytotoxic effects.     

A novel pro-apoptosis gene PNAS4 that induces apoptosis in A549 human lung adenocarcinoma cells and inhibits tumor growth in mice

The gene PNAS4 is a high conservative gene that shares high homology of sequence in various organisms from plants to animals. We found overexpression of human PNAS4 induced apoptosis and arrested cell cycle in S phase in A549 human lung adenocarcinoma cells. In C57BL/6 mice model of Lewis lung carcinoma, overexpression of mouse PNAS4 significantly suppressed tumor growth and prolonged survival time through induction of tumor cell apoptosis, exhibiting effective antitumor. Our original investigations in vitro and vivo indicated PNAS4 is a novel pro-apoptosis gene, which could be used as a potential target of cancer biotherapy in future.     

Effects of karanjin on cell cycle arrest and apoptosis in human A549, HepG2 and HL-60 cancer cells

Background

We have investigated the potential anticancer effects of karanjin, a principal furanoflavonol constituent of the Chinese medicine Fordia cauliflora, using cytotoxic assay, cell cycle arrest, and induction of apoptosis in three human cancer cell lines (A549, HepG2 and HL-60 cells).

Results

MTT cytotoxic assay showed that karanjin could inhibit the proliferation and viability of all three cancer cells. The induction of cell cycle arrest was observed via a PI (propidium iodide)/RNase Staining Buffer detection kit and analyzed by flow cytometry: karanjin could dose-dependently induce cell cycle arrest at G2/M phase in the three cell lines. Cell apoptosis was assessed by Annexin V-FITC/PI staining: all three cancer cells treated with karanjin exhibited significantly increased apoptotic rates, especially in the percentage of late apoptosis cells.

Conclusion

Karanjin can induce cancer cell death through cell cycle arrest and enhance apoptosis. This compound may be effective clinically for cancer pharmacotherapy.     

Induction of apoptosis in human cancer cells by a Bacillus lipopeptide bacillomycin D

A newly isolated and characterized Bacillus amyloliquefaciens strain fiply 3A has been found to produce an extracellular cyclic lipopeptide which structurally resembled bacillomycin D, earlier reported to be produced by Bacillus subtilis. The lipopeptide showed a dose dependent killing of three different human cancer cell lines viz. A549 (alveolar adenocarcinoma), A498 (renal carcinoma) and HCT-15 (colon adenocarcinoma), while not affecting the normal cell line L-132 (pulmonary epithelial cells) when analyzed using MTT assay and FACS analysis. Staining the cells with H₂-DCFDA showed an increase in reactive oxygen species (ROS) formation in the lipopeptide treated cell population. Hoechst 33342 staining of nuclei further indicated apoptosis as a major mechanism of cell death in lipopeptide treated cells and the typical symptoms of apoptosis including cell shrinkage, nuclear condensation and fragmentation of nuclei were observed. Lipopeptide treatment induced extensive DNA damage in the treated cells, which was indicated by a TUNEL assay. Flow cytometric analysis exhibited lipopeptide concentration dependent apoptosis which was further confirmed during clonogenic assay of the lipopeptide treated cells.     

Apoptosis of human lung adenocarcinoma A549 cells induced by prodigiosin analogue obtained from an entomopathogenic bacterium Serratia marcescens

An entomopathogenic bacterial strain SCQ1 was isolated from silkworm (Bombyx mori) and identified as Serratia marcescens via 16S rRNA gene analysis. This strain produces a red pigment that causes acute septicemia of silkworm. The red pigment of strain SCQ1 was identified as prodigiosin analogue (PGA) with various reported biological activities. In this study, we found that low concentration of PGA showed significant anticancer activity in human lung adenocarcinoma A549 cells, but has little effect in human bone marrow stem cells, in vitro. By exposure to different concentrations of PGA for 24 h, morphological changes and the MTT assay showed that A549 cell line was very sensitive to PGA, with IC₅₀ value about 2.2 mg/L. Early stage of apoptosis was detected by flow cytometry while A549 cells were treated with PGA for 4 and 12 h, respectively. The proportion of dead cells was increased with treatment time or the concentrations of PGA, but it was inversely proportional to that of apoptotic cells. These results indicate that PGA obtained from strain SCQ1 induces apoptosis in A549 cells, but the molecular mechanisms of cell death are complicated, and the S. marcescens strain SCQ1 may serve as a source of the anticancer compound, PGA.     

Synthesis and biological evaluation of 1-benzyl-N-(2-(phenylamino)pyridin-3-yl)-1H-1,2,3-triazole-4-carboxamides as antimitotic agents

A library of 1-benzyl-N-(2-(phenylamino)pyridin-3-yl)-1H-1,2,3-triazole-4-carboxamides (7a–al) have been designed, synthesized and screened for their anti-proliferative activity against some selected human cancer cell lines namely DU-145, A-549, MCF-7 and HeLa. Most of them have shown promising cytotoxicity against lung cancer cell line (A549), amongst them 7f was found to be the most potent anti-proliferative congener. Furthermore, 7f exhibited comparable tubulin polymerization inhibition (IC₅₀ value 2.04 µM) to the standard E7010 (IC₅₀ value 2.15 µM). Moreover, flow cytometric analysis revealed that this compound induced apoptosis via cell cycle arrest at G₂/M phase in A549 cells. Induction of apoptosis was further observed by examining the mitochondrial membrane potential and was also confirmed by Hoechst staining as well as Annexin V-FITC assays. Furthermore, molecular docking studies indicated that compound 7f binds to the colchicine binding site of the β-tubulin. Thus, 7f exhibits anti-proliferative properties by inhibiting the tubulin polymerization through the binding at the colchicine active site and by induction of apoptosis.     

Eurycomanone suppresses expression of lung cancer cell tumor markers, prohibitin, annexin 1 and endoplasmic reticulum protein 28

Bioactive compounds from the medicinal plant, Eurycoma longifolia Jack have been shown to promote anti-proliferative effects on various cancer cell lines. Here we examined the effects of purified eurycomanone, a quassinoid found in Eurycoma longifolia Jack extract, on the expression of selected genes of the A549 lung cancer cells. Eurycomanone inhibited A549 lung cancer cell proliferation in a dose-dependent manner at concentrations ranging from 5 to 20 μg/ml. The concentration that inhibited 50% of cell growth (GI₅₀) was 5.1 μg/ml. The anti-proliferative effects were not fully reversible following the removal of eurycomanone, in which 30% of cell inhibition still remained (p < 0.0001, T-test). At 8 μg/ml (GI₇₀), eurycomanone suppressed anchorage-independent growth of A549 cells by >25% (p < 0.05, T-test, n = 8) as determined using soft agar colony formation assay. Cisplatin, a chemotherapy drug used for the treatment of non small cell lung cancer on the other hand, inhibited A549 cells proliferation at concentrations ranging from 0.2 μg/ml to 15 μg/ml with a GI₅₀ of 0.58 μg/ml. The treatment with eurycomanone reduced the abundance expression of the lung cancer markers, heterogeneous nuclear ribonucleoprotein (hnRNP) A2/B1, p53 tumor suppressor protein and other cancer-associated genes including prohibitin (PHB), annexin 1 (ANX1) and endoplasmic reticulum protein 28 (ERp28) but not the house keeping genes. The mRNA expressions of all genes with the exception of PHB were significantly downregulated, 72 h after treatment (p < 0.05, T-test, n = 9). These findings suggest that eurycomanone at viable therapeutic concentrations of 5-20 μg/ml exhibited significant anti-proliferative and anti-clonogenic cell growth effects on A549 lung cancer cells. The treatment also resulted in suppression of the lung cancer cell tumor markers and several known cancer cell growth-associated genes.