Antiproliferative Effect of Amaranth Proteins and Peptides on HT-29 Human Colon Tumor Cell Line

Antiproliferative effect of Amaranthus mantegazzianus proteins and peptides released after simulated gastrointestinal digestion (DH% 37.8?±?3.8) was investigated on human colon cancer cell line HT-29. Inhibition of proliferation of HT-29 cells was exhibited after a 24 h treatment with different concentrations of amaranth protein isolate (API) and the peptides released after digestion (DGS), presenting IC₅₀ values of 1.35?±?0.12 and 0.30?±?0.07 mg soluble protein/mL, respectively. Lactate dehydrogenase assay indicated that both samples caused the loss of membrane integrity and cell lysis over HT-29 cells, and DAPI fluorescence microscopies evidenced typical apoptotic features. Moreover, Annexin V-FITC flow cytometry showed a significant increase of early apoptotic and late apoptotic/necrotic HT-29 cells compared to untreated ones, and caspase-3 assay confirmed the apoptosis induction with a 43.0?±?10.3 and 65.8?±?12.7% increase of caspase-3 activity produced by a 2 mg/mL treatment of API and DGS, respectively. In conclusion, amaranth peptides successfully released after simulated gastrointestinal digestion would exert a potential antiproliferative activity over HT-29 tumor cells. This effect was linked to the induction of cell necrosis and apoptosis, supporting the idea of using amaranth proteins as a potential food alternative ingredient for functional foods.

     

Methanolic Extracts of Uncaria rhynchophylla Induce Cytotoxicity and Apoptosis in HT-29 Human Colon Carcinoma Cells

In this paper, we report the anticancer activities of Uncaria rhynchophylla extracts, a Rubiaceae plant native to China. Traditionally, Uncaria rhynchophylla has been used in the prevention and treatment of neurotoxicity. However, the cytotoxic activity of Uncaria rhynchophylla against human colon carcinoma cells has not, until now, been elucidated. We found that the methanolic extract of Uncaria rhynchophylla (URE) have cytotoxic effects on HT-29 cells. The URE showed highly cytotoxic effects via the MTT reduction assay, LDH release assay, and colony formation assay. As expected, URE inhibited the growth of HT-29 cells in a dose-dependent manner. In particular, the methanolic URE of the 500 microg/ml showed 15.8% inhibition against growth of HT-29 cells. It induced characteristic apoptotic effects in HT-29 cells, including chromatin condensation and sharking occurring 24 h when the cells were treated at a concentration of the 500 microg/ml. The activation of caspase-3 and the specific proteolytic cleavage of poly (ADP-ribose) polymerase were detected over the course of apoptosis induction. These results indicate that URE contains bioactive materials with strong activity, and is a potential chemotherapeutic agent candidate against HT-29 human colon carcinoma cells.     

大豆胚轴体外诱导结肠癌细胞分化的研究

用免疫细胞化学法检测增殖细胞核抗原Ki-67和PCNA蛋白表达,分光光度法测定碱性磷酸酶(ALP)和乳酸脱氢酶(LDH)活性,ELISA法测定癌胚抗原(CEA)水平,研究了富含大豆异黄酮和皂甙的大豆胚轴提取物(SHE)对结肠癌细胞增殖和分化的影响。结果表明:富含大豆异黄酮和皂甙的大豆胚轴提取物可时间和浓度依赖性地降低结肠癌细胞Ki-67和PCNA表达,增加细胞ALP活性。CEA水平和LDH活性呈增高趋势,但差异不具有统计学意义。表明富含大豆异黄酮和皂甙的大豆胚轴可抑制结肠癌细胞增殖和诱导细胞分化,从而发挥抗结肠癌作用。     

Antiproliferative Properties of Scandium Exopolysaccharide Complexes on Several Cancer Cell Lines

Antimetastatic properties on both murine and human osteosarcoma cell lines (POS-1 and KHOS) have been evidenced using exopolysaccharide (EPS) derivatives, produced by Alteromonas infernus bacterium. These derivatives had no significant effect on the cell cycle neither a pro-apoptotic effect on osteosarcoma cells. Based on this observation, these EPSs could be employed as new drug delivery systems for therapeutic uses. A theranostic approach, i.e., combination of a predictive biomarker with a therapeutic agent, has been developed notably by combining with true pair of theranostic radionuclides, such as scandium ⁴⁷Sc/⁴⁴Sc. However, it is crucial to ensure that, once complexation is done, the biological properties of the vector remain intact, allowing the molecular tropism of the ligand to recognize its molecular target. It is important to assess if the biological properties of EPS evidenced on osteosarcoma cell lines remain when scandium is complexed to the polymers and can be extended to other cancer cell types. Scandium-EPS complexes were thus tested in vitro on human cell lines: MNNG/HOS osteosarcoma, A375 melanoma, A549 lung adenocarcinoma, U251 glioma, MDA231 breast cancer, and Caco2 colon cancer cells. An xCELLigence Real Cell Time Analysis (RTCA) technology assay was used to monitor for 160 h, the proliferation kinetics of the different cell lines. The tested complexes exhibited an anti-proliferative effect, this effect was more effective compared to EPS alone. This increase of the antiproliferative properties was explained by a change in conformation of EPS complexes due to their polyelectrolyte nature that was induced by complexation. Alterations of both growth factor-receptor signaling, and transmembrane protein interactions could be the principal cause of the antiproliferative effect. These results are very promising and reveal that EPS can be coupled to scandium for improving its biological effects and also suggesting that no major structural modification occurs on the ligand.     

大豆异黄酮甙元对结肠癌HT-29细胞增殖和凋亡的影响

大豆异黄酮通过促进肿瘤细胞凋亡可抑制多种肿瘤细胞的增殖.从大豆提取大豆异黄酮糖甙,再将其部分水解成其甙元,研究大豆异黄酮甙元抑制结肠癌细胞的增殖和促进其凋亡的作用.采用MTT比色法观察大豆异黄酮甙元对结肠癌HT-29细胞增殖的影响,采用TUNEL染色法检测其对HT-29细胞凋亡的影响,采用免疫细胞化学法检测凋亡相关蛋白bax、bcl-2和p53的表达.结果表明:大豆异黄酮甙元可在20～80 mg·L-1范围内时间和浓度依赖性地抑制结肠癌HT-29细胞增殖和诱导细胞凋亡.用40 mg·L-1大豆异黄酮甙元作用结肠癌HT-29细胞72 h时,细胞生长抑制率为(57.1±4.9)%,其对肿瘤细胞凋亡率为(20.9±2.1)%.免疫组化结果还显示,大豆异黄酮甙元可显著性增加HT-29细胞凋亡相关基因bax蛋白表达和降低bcl-2表达.提示,大豆异黄酮甙元可通过诱导结肠癌细胞凋亡发挥抗结肠癌作用.     

Fucoxanthin@Polyvinylpyrrolidone Nanoparticles Promoted Oxidative Stress-Induced Cell Death in Caco-2 Human Colon Cancer Cells

Fucoxanthin (FX), a natural carotenoid found in seaweed with multiple functional activities, is unstable with a poor water solubility that limits its utilization. This study aimed to improve FX’s stability and bioavailability via the nano-encapsulation of FX in polyvinylpyrrolidone (PVP)-coated FX@PVP nanoparticles (NPs). The FX@PVP NPs were evaluated in terms of their morphology, stability, encapsulation efficiency (EE), loading capacity (LC), and in vitro release to optimize the encapsulation parameters, and a 1:8 FX:PVP ratio was found to perform the best with the highest EE (85.50 ± 0.19%) and LC (10.68 ± 0.15%) and improved FX stability. In addition, the FX@PVP NPs were shown to effectively deliver FX into Caco-2 cancer cells, and the accumulation of FX in these cancer cells showed pro-oxidative activities to ameliorate H₂O₂-induced damage and cell death. The FX@PVP NPs could potentially become a new therapeutical approach for targeted cancer treatment.     

Antiproliferative Activity of Korean Wild Vegetables on Different Human Tumor Cell Lines

This study was conducted to determine the antiproliferative activity of 24 Korean wild vegetables. The methanol extracts of these wild vegetables were used against lung, breast, colon and gastric cancer cells, and the results were assessed by MTT assay. It was found that at the extract concentration of 400 mgL⁻¹ 14 plants exercised antiproliferative activity over 80% against the lung cancer cells, one plant among six—against breast cancer cells, and two plants among six—against colon cancer cells, respectively. Eighteen wild vegetables had the hyperplasia inhibition activity against gastric cancer cells over 23.6% at all extract concentrations, however, only six plants had the antiproliferative activity over 80% in 600 mgL⁻¹. It was found that the extracts from Youngia sonchifolia, Synurus deltoides, Syneilesis palmata, and Cephalonoplos segetum, in concentration of 400 mgL⁻¹ inhibited the hyperplasia of lung cancer cells over 95% and Angelica gigas—both lung and colon cancer cells over 95%. In conclusion, the studied wild vegetables’ methanol extracts possess dose dependent antiproliferative properties, based on their bioactive compounds, mainly polyphenols, but some of them as Hypericum ascyron against lung cancer are not effective and even course harm.     

Inhibitory Effects of Rosemary Extracts, Carnosic Acid and Rosmarinic Acid on the Growth of Various Human Cancer Cell Lines

The leaves of Rosmarinus officinalis harvested from three different locations of Turkey were extracted by both methanolic and supercritical CO₂ extraction. Subsequently, six extracts and the active compounds, carnosic acid, and rosmarinic acid were applied to various human cancer cell lines including NCI-H82 (human, small cell lung, carcinoma), DU-145 (human, prostate, carcinoma), Hep-3B (human, black, liver, carcinoma, hepatocellular), K-562 (human chronic myeloid leukemia), MCF-7 (human, breast, adenocarcinoma), PC-3 (human, prostate, adenocarcinoma) and MDA-MB-231 (human, breast, adenocarcinoma) by MTT assay. Supercritical CO₂ extracts had superior antiproliferative effect compared to the soxhlet extracts. Although the extracts exhibited various cytotoxic effects against different cell lines, comparatively low IC₅₀ values ranging between 12.50 and 47.55 μg/ml were attained against K-562, being the most sensitive cell line. Moreover, carnosic acid caused the lowest cell viability with values ranging from 13 to 30 % at a concentration of 19 μM after 48 h of treatments, resulting in superior antiproliferative effect. Rosemary extract is a potential candidate to be included in the anti-cancer diet with pre-determined doses avoiding toxicity.     

Cytotoxic Effects of Fascaplysin against Small Cell Lung Cancer Cell Lines

Fascaplysin, the natural product of a marine sponge, exhibits anticancer activity against a broad range of tumor cells, presumably through interaction with DNA, and/or as a highly selective cyclin-dependent kinase 4 (CDK4) inhibitor. In this study, cytotoxic activity of fascaplysin against a panel of small cell lung cancer (SCLC) cell lines and putative synergism with chemotherapeutics was investigated. SCLC responds to first-line chemotherapy with platinum-based drugs/etoposide, but relapses early with topotecan remaining as the single approved therapeutic agent. Fascaplysin was found to show high cytotoxicity against SCLC cells and to induce cell cycle arrest in G1/0 at lower and S-phase at higher concentrations, respectively. The compound generated reactive oxygen species (ROS) and induced apoptotic cell death in the chemoresistant NCI-H417 SCLC cell line. Furthermore, fascaplysin revealed marked synergism with the topoisomerase I-directed camptothecin and 10-hydroxy-camptothecin. The Poly(ADP-ribose)-Polymerase 1 (PARP1) inhibitor BYK 204165 antagonized the cytotoxic activity of fascaplysin, pointing to the involvement of DNA repair in response to the anticancer activity of the drug. In conclusion, fascaplysin seems to be suitable for treatment of SCLC, based on high cytotoxic activity through multiple routes of action, affecting topoisomerase I, integrity of DNA and generation of ROS.     

Hierridin B Isolated from a Marine Cyanobacterium Alters VDAC1, Mitochondrial Activity,and Cell Cycle Genes on HT-29 Colon Adenocarcinoma Cells

Background: Hierridin B was isolated from a marine cyanobacterium Cyanobium sp. strain and induced cytotoxicity selectively in HT-29 adenocarcinoma cells. The underlying molecular mechanism was not yet elucidated. Methods: HT-29 cells were exposed to the IC₅₀ concentration of hierridin B (100.2 μM) for 48 h. Non-targeted proteomics was performed using 2D gel electrophoresis and MALDI-TOF/TOF mass spectrometry. The mRNA expression of apoptotic and cell cycle genes were analyzed by real-time PCR. Automated quantification of 160 cytoplasm and mitochondrial parameter was done by fluorescence microscopy using CellProfiler software. Results: Proteomics identified 21 significant different proteins, which belonged to protein folding/synthesis and cell structure amongst others. Increase of VDAC1 protein responsible for formation of mitochondrial channels was confirmed by mRNA expression. A 10-fold decrease of cytoskeleton proteins (STMN1, TBCA) provided a link to alterations of the cell cycle. CCNB1 and CCNE mRNA were decreased two-fold, and P21CIP increased 10-fold, indicative of cell cycle arrest. Morphological analysis of mitochondrial parameter confirmed a reduced mitochondrial activity. Conclusion: Hierridin B is a potential anticancer compound that targets mitochondrial activity and function.     

Geoditin A Induces Oxidative Stress and Apoptosis on Human Colon HT29 Cells

Geoditin A, an isomalabaricane triterpene isolated from the marine sponge Geodia japonica, has been demonstrated to dissipate mitochondrial membrane potential, activate caspase 3, decrease cytoplasmic proliferating cell nuclear antigen (PCNA), and induce apoptosis of leukemia cells, but the underlying mechanism remains unclear [1]. In this study, we found fragmentation of Golgi structure, suppression of transferrin receptor expression, production of oxidants, and DNA fragmentation in human colon cancer HT29 cells after treatment with geoditin A for 24 h. This apoptosis was not abrogated by chelation of intracellular iron with salicylaldehyde isonicotinoyl hydrazone (SIH), but suppressed by N-acetylcysteine (NAC), a thiol antioxidant and GSH precursor, indicating that the cytotoxic effect of geoditin A is likely mediated by a NAC-inhibitable oxidative stress. Our results provide a better understanding of the apoptotic properties and chemotherapeutical potential of this marine triterpene.     

大豆异黄酮和皂甙对结肠癌细胞增殖和凋亡的研究

从大豆胚轴提取大豆异黄酮和皂甙,研究大豆异黄酮和皂甙抑制结肠癌细胞的增殖和促进其凋亡的作用.采用MTT比色法观察大豆异黄酮和皂甙抑制结肠癌细胞增殖,采用流式细胞仪检测大豆异黄酮和皂甙对HT-29细胞周期分布的影响,免疫细胞化学法检测凋亡相关蛋白bax、bcl-2和p53的表达.结果表明:大豆异黄酮和皂甙可时间和浓度依赖性地抑制结肠癌细胞增殖;诱导细胞凋亡和改变细胞周期分布,多数细胞阻滞于G/2M期;与对照组比较,细胞凋亡率显著增加;用药前后凋亡相关基因bax蛋白表达显著增加,bcl-2表达显著降低.提示,大豆异黄酮和皂甙可通过改变细胞周期分布和诱导结肠癌细胞凋亡,发挥抗结肠癌作用.     

Aqueous Extract of Sea Squirt (Halocynthia roretzi) with Potent Activity against Human Cancer Cells Acts Synergistically with Doxorubicin

Marine ascidian is becoming one of the main sources of an antitumor drug that has shown high bioactivity and extensive application in cancer treatment. Halocynthia roretzi, an edible marine sea squirt, has been demonstrated to have various kinds of biological activities, such as anti-diabetic, anti-hypertension, and enhancing immunity. In this study, we reported that aqueous extracts from the edible parts of H. roretzi presented significantly inhibiting the efficiency on HepG-2 cell viability. The separate mixed compound exhibited strong effects of inhibitory proliferation and induced apoptosis via the generation of ROS along with the concurrent loss of mitochondrial membrane potential on tumor cells. Furthermore, we found that there existed a significantly synergistic effect of the ascidian-extracted compound mixture with the anti-cancer drug doxorubicin. In the presence of the extracts from H. roretzi, the dose of doxorubicin at the cellular level could be reduced by a half dose. The extracts were further divided by semipreparative-HPLC and the active ingredients were identified as a mixture of fatty amide, which was composed of hexadecanamide, stearamide, and erucamide by UHPLC-MS/MS. Our results suggest that the potential toxicity of ascidian H. roretzi in tumor cells, and the compounds extracted from H. roretzi could be potentially utilized on functional nutraceuticals or as an adjunct in combination with chemotherapy.     

Antiproliferative Activity of Cyanophora paradoxa Pigments in Melanoma,Breast and Lung Cancer Cells

The glaucophyte Cyanophora paradoxa (Cp) was chemically investigated to identify pigments efficiently inhibiting malignant melanoma, mammary carcinoma and lung adenocarcinoma cells growth. Cp water and ethanol extracts significantly inhibited the growth of the three cancer cell lines in vitro, at 100 µg·mL⁻¹. Flash chromatography of the Cp ethanol extract, devoid of c-phycocyanin and allophycocyanin, enabled the collection of eight fractions, four of which strongly inhibited cancer cells growth at 100 µg·mL⁻¹. Particularly, two fractions inhibited more than 90% of the melanoma cells growth, one inducing apoptosis in the three cancer cells lines. The detailed analysis of Cp pigment composition resulted in the discrimination of 17 molecules, ten of which were unequivocally identified by high resolution mass spectrometry. Pheophorbide a, β-cryptoxanthin and zeaxanthin were the three main pigments or derivatives responsible for the strong cytotoxicity of Cp fractions in cancer cells. These data point to Cyanophora paradoxa as a new microalgal source to purify potent anticancer pigments, and demonstrate for the first time the strong antiproliferative activity of zeaxanthin and β-cryptoxanthin in melanoma cells.     

Metabolomic Characterization of a cf. Neolyngbya Cyanobacterium from the South China Sea Reveals Wenchangamide A,a Lipopeptide with In Vitro Apoptotic Potential in Colon Cancer Cells

Metabolomics can be used to study complex mixtures of natural products, or secondary metabolites, for many different purposes. One productive application of metabolomics that has emerged in recent years is the guiding direction for isolating molecules with structural novelty through analysis of untargeted LC-MS/MS data. The metabolomics-driven investigation and bioassay-guided fractionation of a biomass assemblage from the South China Sea dominated by a marine filamentous cyanobacteria, cf. Neolyngbya sp., has led to the discovery of a natural product in this study, wenchangamide A (1). Wenchangamide A was found to concentration-dependently cause fast-onset apoptosis in HCT116 human colon cancer cells in vitro (24 h IC₅₀ = 38 μM). Untargeted metabolomics, by way of MS/MS molecular networking, was used further to generate a structural proposal for a new natural product analogue of 1, here coined wenchangamide B, which was present in the organic extract and bioactive sub-fractions of the biomass examined. The wenchangamides are of interest for anticancer drug discovery, and the characterization of these molecules will facilitate the future discovery of related natural products and development of synthetic analogues.     

Anti-proliferative Effect of <Emphasis Type="Italic">Melissa officinalis</Emphasis> on Human Colon Cancer Cell Line

Melissa officinalis L. (Lamiaceae) is consumed as a traditional herbal tea in the Mediterranean region. The cytotoxic effect of the 50% ethanolic and aqueous extract, determined by the MTT and NR assays, was evaluated in vitro on Human Colon Cancer Cell Line (HCT-116), using Triton 10% as positive control. The 50% ethanolic extract showed significant differences after 72 h of treatment, reducing cell proliferation to values close to 40%, even the lowest dose tested (5 μg/ml). In the MTT assay, the same extract caused the lowest cell viability with 13% at a concentration of 1,000 μg/ml after 72 h of treatment, being a value lower than Triton 10%. The antioxidant activity was also confirmed evaluating the capacity of the extracts to scavenge ABTS and DPPH radicals, and IC₅₀ values were highly correlated with the total phenolic and flavonoid content. Bioassay guided fractionation led to the isolation of an anti-proliferative compound, rosmarinic acid. Its structural elucidation was performed by HPLC/DAD/ESI/MS analysis. High dose of rosmarinic acid (1,000 μg/ml) was clearly cytotoxic against HCT-116 cells, with a significant decrease in cell number since the earliest time point (24 h).     

Cytotoxic Effect of Natural trans-Resveratrol Obtained from Elicited Vitis vinifera Cell Cultures on Three Cancer Cell Lines

trans-Resveratrol (trans-R) has been reported to be a potential cancer chemopreventive agent. Although its cytotoxic activity against different cancer cell lines has been tested, its effect on human acute leukemia cell lines has scarcely been investigated, and only a few in vitro studies were performed using human breast epithelial cell lines. Due to its potential value for human health, demand for trans-R has rapidly increased, and new biotechnological strategies to obtain it from natural edible sources have been developed. Thus, grapevine cell cultures represent a reliable system of trans-R production since they biosynthesize trans-R constitutively or in response to elicitation. In addition, there are no studies deepen on the inhibitory effect of trans-R, produced by elicited grapevine cell cultures, on growth of human tumor cell lines. In this work, the effect of trans-R extracted from the culture medium, after elicitation of grapevine cell cultures, was tested on two human acute lymphocytic and monocytic leukemia cell lines, and one human breast cancer cell line. The effect of trans-R on cell proliferation was not only dose- and time-dependent but also cell type-dependent, as seen from the different degrees of susceptibility of cancer cell lines tested. As regards the effect of trans-R on cell cycle distribution, low trans-R concentrations increased cells in the S phase whereas a high trans-R concentration increased G₀/G₁ phase in all cell lines. Perturbation of the cell cycle at low trans-R concentrations did not correlate with the induction of cell death, whereas a high trans-R concentration, cell proliferation decreased as a result of increasing apoptosis in the three cell lines. In leukemia cells, trans-R up-regulated the expression of caspase-3 while trans-R-induced apoptosis in breast cells occur through a caspase-3-independent mechanism mediated by a down-regulation of Bcl-2.