To date little has been done on identification of major phenolic compounds responsible for anticancer and antioxidant properties of pea (Pisum sativum L.) seed coat extracts. In the present study, phenolic profile of the seed coat extracts from 10 differently colored European varieties has been determined using ultrahigh-performance liquid chromatography-linear trap quadrupole orbitrap mass spectrometer technique. Extracts of dark colored varieties with high total phenolic content (up to 46.56 mg GAE/g) exhibited strong antioxidant activities (measured by 2,2-diphenyl-1-picrylhydrazyl or DPPH assay, and ferric ion reducing and ferrous ion chelating capacity assays) which could be attributed to presence of gallic acid, epigallocatechin, naringenin, and apigenin. The aqueous extracts of dark colored varieties exert concentration-dependent cytotoxic effects on all tested malignant cell lines (human colon adenocarcinoma LS174, human breast carcinoma MDA-MB-453, human lung carcinoma A594, and myelogenous leukemia K562). Correlation analysis revealed that intensities of cytotoxic activity of the extracts strongly correlated with contents of epigallocatechin and luteolin. Cell cycle analysis on LS174 cells in the presence of caspase-3 inhibitor points out that extracts may activate other cell death modalities besides caspase-3-dependent apoptosis. The study provides evidence that seed coat extracts of dark colored pea varieties might be used as potential cancer-chemopreventive and complementary agents in cancer therapy.

A novel biflavonoid [kaempferol (6→8″) apigenin] was isolated from the leaves of Jacaranda acutifolia. The structure was elucidated based on chemical evidence, 1D and 2D spectroscopic analyses as well as spectrometric techniques. The compound showed promising cytotoxic activity against breast cancer cell line MCF-7. The anticancer activity was explained via virtual docking of the isolated compound to the main sites in the human cyclin-dependent kinase2 (CDK2) crystal structure.

A series of nitrogen-containing apigenin analogs 4a-j was synthesized via Mannich reactions to develop anticancer, antibacterial, and antioxidant agents from plant-derived flavonoids. The chemical structures of these compounds were confirmed using (1)H-NMR, (13)C-NMR, and ESI-MS. The in vitro biological activities of the analogs were evaluated via assays of their antiproliferative, antibacterial, and antioxidant activities. The prepared apigenin analogs exhibited different antiproliferative activities against four human cancer cell lines, namely human cervical (HeLa), human hepatocellular liver (HepG2), human lung (A549), and human breast (MCF-7) cancer cells. Compound 4i showed the most favorable in vitro antiproliferative activity with IC50 values of 40, 40, 223, and 166 μg/mL against HeLa, HepG2, A549, and MCF-7, respectively. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity assay also showed that 4i had the most potent antioxidant activity, with the smallest IC(50) value (334.8 μg/mL). The antibacterial activities of the analogs were determined using a two-fold serial dilution technique against four pathogenic bacteria, namely Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa. All the prepared apigenin analogs exhibited more potent activities than the parent apigenin. Compounds 4h and 4j, in particular, exhibited the best inhibitory activities against the Gram-positive bacteria Staphylococcus aureus and Bacillus subtilis with MIC values of 3.91 and 1.95 μg/mL, respectively.

BACKGROUND

Breast cancer is one of the most common cancers diagnosed among women. It is now recognized that two receptors mediate estrogen action and the presence of estrogen receptor alpha (ERα) correlates with better prognosis and the likelihood of response to hormonal therapy. ERα is an attractive target for the treatment of breast cancer. Most of the drug currently used for the breast cancer treatment that has numerous side effects and often unsuccessfully to remove the tumour completely. Hence, we focused on natural compounds like flavonoids, polyphenols, etc. which do not exhibit any high toxic effects against normal cells.

OBJECTIVE

To identify the potential natural inhibitors for BCa through an optimised in silico approach.

METHODS

Structural modification and molecular docking-based screening approaches were imposed to identify the novel natural compounds by using Schrödinger (Maestro 9.5). The Qikprop v3.5 was used for the evaluation of important ADME parameters and its permissible ranges. Cytotoxicity of the compounds was evaluated by MTT assay against MCF-7 Cell lines.

RESULTS

From the docking studies, we found that the compounds, Myricetin, Quercetin, Apigenin, Luteolin and Baicalein showed the highest Glide Scores -10.78, -9.48, -8.92, -8.87 and -8.82 kcal mol-1 respectively. Of these, Luteolin and Baicalein showed the significant IC50 values (25 ± 4.0 and 58.3 ± 4.4 μM, respectively) against MCF-7 cell line. The ADME profiling of the test compounds was evaluated to find the drug-likeness and pharmacokinetic parameters.

CONCLUSIONS

We mainly focused on in silico study to dock the compounds into the human estrogen receptor ligand binding domain (hERLBD) and compare their predicted binding affinity with known antiestrogens. Myricetin, Quercetin, Apigenin, Luteolin and Baicalein were identified as most promising among all. Of these, Luteolin and Baicalein showed the significant anticancer activities against MCF-7 cell line. These findings may provide basic information for the development of anti-breast cancer agents.

Species in the Juncaceae accumulate different types of secondary metabolites, among them phenanthrenes and 9,10-dihydrophenanthrenes in substantial amounts. These compounds have chemotaxonomic significance and also possess interesting pharmacological activities. The present study has focused on the isolation, structure determination, and pharmacological investigation of phenanthrenes from <i>Juncus gerardii</i>. Twenty-six compounds, including 23 phenanthrenes, have been isolated from a methanol extract of this plant. Twelve compounds, the phenanthrenes gerardiins A-L (<b>1</b>-<b>12</b>), were obtained as new natural products. Eleven phenanthrenes [effusol (<b>13</b>), dehydroeffusol (<b>14</b>), effususin A (<b>15</b>), compressin A, 7-hydroxy-2-methoxy-1-methyl-5-vinyl-9,10-dihydrophenanthrene, juncusol, 2-hydroxy-7-hydroxymethyl-1-methyl-5-vinyl-9,10-dihydrophenanthrene, 2,7-dihydroxy-5-formyl-1-methyl-9,10-dihydrophenanthrene, effususol A, 2,7-dihydroxy-5-hydroxymethyl-1-methyl-9,10-dihydrophenanthrene, and jinflexin C], 1-<i>O</i>-<i>p</i>-coumaroyl-3-<i>O</i>-feruloyl-glycerol, and the flavones <em>apigenin</em> and luteolin were isolated for the first time from this plant. The cytotoxicity of the 23 isolated phenanthrenes in both mouse (4T1) and human (MDA-MB-231) triple-negative <em>breast</em> cancer cells and in a nontumor (D3, human cerebral microvascular endothelial) cell line was tested using an MTT viability assay. The results obtained showed that the dimeric compounds gerardiins I (<b>9</b>), J (<b>10</b>), K (<b>11</b>), and L (<b>12</b>), derived biogenetically from effusol and dehydroeffusol, were cytotoxic to both tumor and nontumor cell lines, while the monomeric compounds exerted no or very low cytotoxicity. Impedance measurements were consistent with the results of the MTT assays performed.

Background: Cancer is a horrific disease relentlessly affecting human population round the globe. Genus Datura encompasses numerous species with reported medicinal uses. However, its potential as a source of natural anticancer agents is yet to be determined. Datura stramonium (DS) and Datura inoxia (DI) are the two species chosen for this study.

Methods: Total phenolic and flavonoid content (TPC and TFC) as well as antioxidant activity were assessed through colorimetric method. Polyphenolic quantification was done by RP-HPLC. Following extract standardization ethyl acetate leaf extracts of both species (DSL-EA and DIL-EA) were chosen for anticancer studies. In vitro cytotoxicity using various models including cancer cell lines was monitored. Following toxicity studies, benzene (0.2 ml) was used to induce leukemia in Sprague-Dawley rats. Extracts were orally administered to preventive (100 and 200 mg/kg) and treatment (200 mg/kg only) groups. The antileukemic potential of extracts was assessed through haematological, biochemical, endogenous antioxidants and histological parameters.

Results: Significant TPC and TFC were estimated in DSL-EA and DIL-EA. RP-HPLC quantified (μg/mg extract) rutin (0.89 ± 0.03), gallic acid (0.35 ± 0.07), catechin (0.24 ± 0.02) and apigenin (0.29 ± 0.09) in DSL-EA while rutin (0.036 ± 0.004) and caffeic acid (0.27 ± 0.03) in DIL-EA. Both extracts exhibited significant brine shrimp cytotoxicity (LC₅₀ < 12.5 μg/ml). DIL-EA exhibited greater cytotoxicity against PC-3, MDA-MB 231 and MCF-7 cell lines (IC₅₀ < 3 μg/ml in each case) as well as higher protein kinase inhibitory action (MIC: 25 μg/disc) compared to DSL-EA. Leukemia induced in rats was affirmed by elevated serum levels of WBCs (7.78 ± 0.012 (× 10³) /μl), bilirubin (7.56 ± 0.97 mg/dl), Thiobarbituric acid reactive substances (TBARs) (133.75 ± 2.61 nM/min/mg protein), decreased RBCs (4.33 ± 0.065 (× 10⁶)/μl), platelets (344 ± 3.19 (× 10³)/μl), total proteins (2.14 ± 0.11 g/dl), Glutathione S-transferases (GST) (81.01 ± 0.44 nM/min/ml), endogenous antioxidant enzymes levels and abnormal liver and kidney functionality in disease control rats. Both species revealed almost identical and significant (p < 0.05) alleviative effects in benzene induced leukemia.

Conclusion: Comprehensive screening divulged the tremendous potential of selected species as potent source of natural anticancer agents in a variety of cancers particularly leukemia. Present study might provide useful finger prints in cancer research and mechanistic studies are prerequisite in logical hunt of this goal.

Keywords: Anticancer; Antileukemic; Benzene toxicity; Breast cancer; Datura inoxia; Datura stramonium; Prostate cancer.

Catharanthus roseus (L.) G. Don (C. roseus) is a well-known medicinal plant for its source of alkaloids solely found in the leaves. Other parts including the root are usually discarded after the alkaloid extraction. This study sought to investigate phytochemical profiles, antioxidant, antimicrobial and cytotoxic properties of the C. roseus root extract (RE) and its two sub-fractions including saponin-enriched (SE) and aqueous (AQ) fractions. The results showed that the RE was a rich source of saponins (1744.44 mg ESE/g) and phenolics (51.27 mg GAE/g), which comprised of gallic acid (25.74 mg/g), apigenin (1.45 mg/g) and kaempferol (1.58 mg/g). The SE fraction was enriched with 31% of saponins and 63% of phenolics higher than those of the RE; whereas the concentrations of saponins and phenolics of the AQ fraction were lower than those of the RE by 40% and 74%, respectively. The content of gallic acid in the SE fraction was 1.4-fold and 1.5-fold higher than those of the RE or AQ fraction, respectively. The SE fraction demonstrated potent antioxidant capacity, which was significantly higher than the RE or AQ fraction, and also exhibited strong anti-proliferative activity against 11 cancer cell lines including A2780 (ovarian), H460 (lung), A431 (skin), MIA PaCa-2 (pancreas), Du145 (prostate), HT29 (colon), MCF-7 (breast), BE2-C (neuroblastoma), SJ-G2, U87 and SMA (glioblastoma) with low GI₅₀ values (≤ 2.00 µg/mL). The SE fraction was also shown to effectively inhibit the growth of both bacteria (Escherichia coli, Enterobacter aerogenes and Staphylococccus lugdunensis) and fungi (Candida albicans and Aspergillus niger). These findings warrant further investigation to isolate major compounds from the SE fraction and further test their antioxidant, anticancer and antimicrobial activities.

The high demand for healthy food in recent years has led to an increasing need for highly bioactive plant materials. One such plant, Chinese cabbage, possesses flavonoids with antioxidant and antidiabetic properties, but they appear in low quantities. The interspecific transfer of metabolites is a promising technique that could contribute to the increase of the beneficial properties of food. The objective of the study was to determine how an interspecific source-sink phytochemical transfer from donor extracts to the Chinese cabbage affects its phenolic and vitamin C profile and intestinal bioaccessibility, hypoglycemic potential and antioxidant capacity. In addition, sprouts treated with Rosa sp. and Hypericum perforatum extracts showed better antiproliferative effect towards human breast adenocarcinoma cells than untreated sprouts. The results suggest that treatment of plants with donor extracts is a promising approach to improve the nutritional and phytochemical profile and bioactive properties of acceptor plants.

Keywords: Antidiabetic activity; Antioxidant capacity; Antiproliferative effect; Apigenin (PubChem CID: 5280443); Caffeic acid (PubChem CID: 689043); Ferulic acid (PubChem CID: 445858); Gastrointestinal bioavailability; Interspecies phytochemical transfer; Kaempferol (PubChem CID: 5280863); L-Ascorbic acid (PubChem CID: 54670067); Luteolin (PubChem CID: 5280445); Myricetin (PubChemi CID: 5281672); Phenolics; Quercetin (PubChem CID: 5280343); RP-HPLC; Sinapic acid (PubChem CID: 637775); p-Coumaric acid (PubChem CID: 637542); qRT-PCR.

Approximately 80% of breast cancer (BC) cases express the estrogen receptor (ER), and 30-40% of these cases acquire resistance to endocrine therapies over time. Hyperactivation of Akt is one of the mechanisms by which endocrine resistance is acquired. Apigenin (Api), a flavone found in several plant foods, has shown beneficial effects in cancer and chronic diseases. Here, we studied the therapeutic potential of Api in the treatment of ER-positive, endocrine therapy-resistant BC. To achieve this objective, we stably overexpressed the constitutively active form of the Akt protein in MCF-7 cells (named the MCF-7/Akt clone). The proliferation of MCF-7/Akt cells is partially independent of estradiol (E2) and exhibits an incomplete response to the anti-estrogen agent 4-hydroxytamoxifen, demonstrating the resistance of these cells to hormone therapy. Api exerts an antiproliferative effect on the MCF-7/Akt clone. Api inhibits the proliferative effect of E2 by inducing G2/M phase cell cycle arrest and apoptosis. Importantly, Api inhibits the Akt/FOXM1 signaling pathway by decreasing the expression of FOXM1, a key transcription factor involved in the cell cycle. Api also alters the expression of genes regulated by FOXM1, including cell cycle-related genes, particularly in the MCF-7/Akt clone. Together, our results strengthen the therapeutic potential of Api for the treatment of endocrine-resistant BC.

Keywords: Akt; ER; FOXM1; apigenin; breast cancer; endocrine resistance; phytochemicals.

The objective of this work was to develop sustained-release Ca-alginate beads of apigenin using sodium alginate, a natural polysaccharide. Six batches were prepared by applying the ionotropic gelation technique, wherein calcium chloride was used as a crosslinking agent. The beads were evaluated for particle size, drug loading, percentage yield, and in vitro drug release. Particle size was found to decrease, and drug entrapment efficiency was enhanced with an increase in the polymer concentration. The dissolution study showed sustained drug release from the apigenin-loaded alginate beads with an increase in the polymer proportion. Based on the dissolution profiles, BD6 formulation was optimized and characterized for FTIR, DSC, XRD, and SEM, results of which indicated successful development of apigenin-loaded Ca alginate beads. MTT assay demonstrated a potential anticancer effect against the breast cancer MCF-7 cell lines. The antimicrobial activity exhibited effective inhibition in the bacterial and fungal growth rate. The DPPH measurement revealed that the formulation had substantial antioxidant activity, with EC50 value slightly lowered compared to pure apigenin. A stability study demonstrated that the BD6 was stable with similar (fapigenin while also improving in vitro antitumor, antimicrobial, and antioxidant activity.

Keywords: Ca-alginate; DPPH; DSC; FTIR; MTT; SEM; XRD; antimicrobial; apigenin; beads; in vitro dissolution.

Vernonia amygdalina Delile (Asteraceae) is used in traditional medicine to treat diabetes mellitus, and some research provides its activity to treat breast cancer. The aim of this study is to assess the anticancer activity of Vernonia amygdalina Delile leaves fractions on 4T1 breast cancer cells. Analysis of phytochemical compounds were carried out with LC-MS/MS. Cytotoxic activity was determined using the MTT method in the 4T1 cell line. Apoptosis, the cell cycle, and PI3K and mTOR profiles were analyzed with flow cytometry. The phytochemicals found were diterpene (ingenol-3-angelate) and some phenolics (chlorogenic acid and 4-methoxycinnamic acid), flavonoids (apigetrin, apigenin, luteolin, diosmetin, baicalin, rhoifolin, and scutellarin), and coumarines (7-hydroxycoumarine, 4-methylumbelliferone, and 4-methylumbelliferyl glucuronide). The results of the MTT assay showed that the IC₅₀ values n-hexane fraction, ethylacetate fraction (EAF), and ethanol fractions were 1,860.54 ± 93.11, 25.04 ± 0.36, and 1,940.84 ± 96.37 μg/mL, respectively. EAF induced early and late apoptosis, inhibited cell cycle progression on the G₂/M phase, and inhibited PI3K and mTOR expression. The EAF of Vernonia amygdalina Delile leaves showed anticancer activity on 4T1 breast cancer cells through induction of apoptosis, enhanced cell accumulation on G₂/M phases in the cell cycle, and inhibited expression of PI3K and mTOR.

Keywords: Anticancer; Bioinformatics; Breast cancer; Cancer research; Fraction; Immunology; Leaves; Molecular biology; Toxicology; Vernonia amygdalina Delile.

Breast cancer is the most common carcinoma in women, and natural products would be effective preventing some side effects of cancer treatment. In the present study, cytotoxic activities of different Iranian Chrysanthemum morifolium cultivars were evaluated in human breast cancer cell lines (MCF-7) and human lymphocytes. A systems pharmacology approach was employed between major compounds of these cultivars (chlorogenic acid, luteolin, quercetin, rutin, ferulic acid, and apigenin) and known breast cancer drugs (tucatinib, methotrexate, tamoxifen, and mitomycin) with 22 breast cancer-related targets to analyze the mechanism through which Chrysanthemum cultivars act on breast cancer. Target validation was performed by the molecular docking method. The results indicated that Chrysanthemum extracts inhibited the proliferation of MCF7 cells in a dose- and cultivar-dependent manner. In all studied cultivars, the most effective extract concentration with the lowest viability of MCF-7 cells, was as much as 312 µg ml^-1. Also, higher concentrations of the extracts (> 1000 µg ml^-1) reduced the lymphocyte cell viability, demonstrating that these doses were toxic. The gene ontology analysis revealed the therapeutic effects of Chrysanthemum's active compounds on breast cancer by regulating the biological processes of their protein targets. Moreover, it has been documented that rutin, owing to its anticancer effects and several other health benefits, is a promising multi-targeted herbal ingredient. Finally, the present study compared different Iranian Chrysanthemum cultivars to provide new insights into useful pharmaceutical applications.

Morroniside is a biologically active polyphenol found in Cornus officinalis Sieb. et Zucc (CO) that exhibits a broad spectrum of pharmacological activities, such as protecting nerves, and preventing diabetic liver damage and renal damage. However, little data are available regarding the mechanism of its intestinal absorption. Here, an in vitro human intestinal epithelial cell model of cultured Caco-2 cells was applied to study the absorption and transport of morroniside. The effects of donor concentration, pH and inhibitors were investigated. The bidirectional permeability of morroniside from the apical (AP) to the basolateral (BL) side and in the reverse direction was studied. When administered at three tested concentrations (5, 25 and 100 μM), the apparent permeability coefficient (Papp) values in the AP-to-BL direction ranged from 1.59 × 10-6 to 2.66 × 10-6 cm/s. In the reverse direction, BL-to-AP, the value was ranged from 2.67 × 10-6 to 4.10 × 10-6 cm/s. The data indicated that morroniside transport was pH-dependent. The permeability of morroniside was affected by treatment with various inhibitors, such as multidrug resistance protein inhibitors MK571 and indomethacin, as well as the breast cancer resistance protein inhibitor apigenin. The mechanisms of the intestinal absorption of morroniside may involve multiple transport pathways, such as the passive diffusion and efflux protein-mediated active transport especially involving multidrug resistance protein 2 and breast cancer resistance protein. After the addition of CO, the Papp values in the AP-to-BL direction increased significantly, therefore, it can be assumed that some ingredients in the CO promote morroniside absorption in the small intestine.

OBJECTIVE

To study the effects and mechanism of apigenin on the expression of vascular endothelial growth factor (VEGF) in human breast cancer MDA-MB-231 cells.

METHODS

MDA-MB-231 cells were used as the study object. MTT assay was used to detect the effect of apigenin on the cell viability. ELISA was used to determine the protein level of VEGF. RT-PCR was used to detect VEGF at mRNA level. A double luciferase system was used to measure the transcription activity of VEGF. pCEP4-HIF-1alpha was transferred to explore the reversing effect of HIF-1alpha on the inhibitory effect of apigenin on the transcription activity of VEGF. Western blotting was used to detect the time-dependent and dose-dependent effect of apigenin on HIF-lalpha, p-AKT, p-ERK, and p53 expression at protein level.

RESULTS

Apigenin had no visible inhibitory effect on cell viability. Apigenin reduced the secretion of VEGF, mRNA levels of VEGF and transcription activity of VEGF. Furthermore, the inhibitory effect of apigenin on the transcription activity of VEGF could be reversed by transferring pCEP4-HIF-1alpha into the cells. Additionally, apigenin inhibited the expression of HIF-1alpha and p-AKT, induced the expression of p53, but had no effect on the expression of p-ERK1/2.

CONCLUSIONS

Apigenin can inhibit VEGF expression in breast cancer cells, and this effect may be achieved through decreasing the expression of HIF-1alpha.

Background: Breast Cancer (BC), a common death-causing disease and the deadliest cancer next to lung cancer, is characterized by an abnormal growth of cells in the tissues of the breast. BC chemotherapy is marked by targeting the activities of some receptors such as Estrogen Receptor alpha (ER-α). At present, one of the most commonly used and approved marketed therapeutic drug for BC is tamoxifen. Despite the short term success of tamoxifen usage, its long time treatment has been associated with significant side effects. Therefore, there is a pressing need for the development of novel anti-estrogens for the prevention and treatment of BC.

Objective: In this study, we evaluate the inhibitory effect of Cannabis Sativa phyto-constituents on ER-α.

Method: Glide and Induced Fit Docking followed by ADME, Automated QSAR and Binding free energy (ΔGbind) studies were used to evaluate the anti-breast cancer and ER-α inhibitory activity of Cannabis sativa, which has been reported to be effective in inhibiting breast cancer cell proliferation.

Results: Phyto-constituents of Cannabis sativa possess lower docking scores and good ΔGbind when compared to that of tamoxifen. ADME and AutoQSAR studies revealed that our lead compounds demonstrated the properties required to make them promising therapeutic agents.

Conclusion: The results of this study suggest that Naringenin, Dihydroresveratrol, Baicalein, Apigenin and Cannabitriol could have relatively better inhibitory activity than tamoxifen and could be a better and patent therapeutic candidate in the treatment of BC. Further research such as in vivo and/or in vitro assays could be conducted to attest the ability of these compounds.

Keywords: ADME; AutoQSAR; MM-GBSA.; breast cancer; cancer; docking; estrogen; induced fit docking.

Recurrence of estrogen receptor (ER)-positive breast tumors despite curative-intent adjuvant therapy is thought to be due to enrichment of tumor initiating cells (TIC) during endocrine therapy (ET). Recently, it was identified that by antagonizing the ER, ET promotes rapid degradation of the death-associated factor 6 (DAXX) protein, which is necessary and sufficient to potently inhibit TICs. Thus, the goal of the current study was to identify a DAXX-inducing agent to inhibit TICs and prevent proliferation of the tumor. Phytoestrogens (naringenin, resveratrol, genistein, apigenin, and quercetin) were screened for DAXX protein expression, anti-TIC and anti-proliferative efficacy in vitro and in vivo. Specific DAXX-inducing phytoestrogens were tested to assess selectivity towards ERα and/or ERβ. Results showed that phytoestrogens tested induced DAXX protein expression and inhibited survival of TICs from ER+ MCF-7 and T47D cells. Only naringenin, resveratrol, and quercetin did not stimulate total cell proliferation. Naringenin, resveratrol, but not quercetin inhibited survival of TICs in vitro and in vivo in a DAXX-dependent manner. Naringenin-induced DAXX protein expression and inhibition of TICs seemed to be more selective towards ERβ while resveratrol was more selective through ERα. Naringenin or resveratrol inhibited the rate of tumor initiation and rate of tumor growth in a DAXX-dependent manner. These results suggest that a therapeutic approach using a phytoestrogen to induce DAXX protein expression could potently inhibit TICs within a tumor to delay or prevent tumor initiation. Therefore, a DAXX-promoting phytoestrogen should be explored for prevention of tumor progression in advanced disease and relapse in the adjuvant setting.

Purpose: In vitro and in vivo studies suggested that flavonols, flavones, flavanones and flavan-3-ols have preventive effects on breast carcinogenesis. Epidemiological evidence about the associations between these flavonoid biomarkers and breast cancer risk is limited. This study aimed to investigate the association between serum concentration of these flavonoids and breast cancer risk among Chinese women.

Methods: This hospital-based case-control study recruited 792 breast cancer cases and 813 age frequency-matched (5-year interval) controls who provided eligible blood samples in Guangdong Province, China. Ultra-high-performance liquid chromatography-tandem mass spectrometry was used to measure flavonoids. Unconditional logistic regression was used to estimate the odds ratio (OR) and 95% confidence internal (CI).

Results: Higher concentrations of serum flavonols, isorhamnetin, kaempferol, flavanones and naringenin were significantly associated with lower breast cancer risk, with adjusted ORs (95% CIs) for the highest versus the lowest group of 0.66 (0.49-0.89) for flavonols, 0.52 (0.38-0.70) for isorhamnetin, 0.60 (0.45-0.80) for kaempferol, 0.65 (0.49-0.87) for flavanones and 0.45 (0.34-0.60) for naringenin, respectively. Significant positive associations were observed between serum flavan-3-ols, epigallocatechin, epigallocatechin-3-gallate and breast cancer risk. No significant associations were observed for serum quercetin, flavones, apigenin, luteolin, hesperetin, catechin, epicatechin and epicatechin-3-gallate with overall breast cancer risk.

Conclusions: This study suggested that serum flavonols and flavanones were inversely associated with breast cancer risk and serum flavan-3-ols were positively associated with breast cancer risk. Serum flavones were not associated with overall breast cancer risk. These findings warrant further confirmation in prospective studies.

Keywords: Breast cancer; Case–control study; Flavonoids; Polyphenols; Serum.

UNASSIGNED

Dipterygium glaucum Decne. herb is one of the common traditional plants with multiple medicinal uses.

UNASSIGNED

To isolate the major constituents and to investigate the antioxidant, antimicrobial, and cytotoxic activities of this herb.

UNASSIGNED

Methanolic extract of D. glaucum herb was fractionated using n-hexane, dichloromethane, and n-butanol. Butanol fraction was chromatographed using column chromatography and preparative thin layer chromatography to isolate the major constituents. Isolated compounds were elucidated by means of spectroscopic methods, including 1D, 2D NMR (1H, 13C, DEPT, COSY, HSQC, HMBC, NEOSY) and MS analysis. Total phenolic content using Folin-Ciocalteu reagent and antioxidant activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay of the total methanolic extract were evaluated. Cytotoxic potential of both methanolic extract and butanol fraction was tested using a crystal violet viability assay. Antimicrobial activities of both extracts were investigated using diffusion agar technique.

UNASSIGNED

Apigenin 6, 8-di-C-glucopyranoside (vicenin-2), quercetin-3`-O-methyl-3-O-glucopyranoside, quercetin-3`-O-methyl-3-O-galactopyranoside, quercetin-3-O-β-D-glucopyranoside, and quercetin-3-O-β-D-galactopyranoside were isolated and elucidated. Total phenolic content was (83.89 mg gallic acid equivalent/g extract). The EC50 value of scavenging DPPH radical was 152.0 ± 2 mg/mL. Butanol fraction showed the highest cytotoxic activity against cervical and breast carcinoma cells (IC50 3.6 and 6.1 mg/mL, respectively). Both methanolic extract and butanol fraction showed wide spectrum antimicrobial activity against Gram-positive and Gram-negative bacteria and some fungi. The highest activity was from methanolic extract against Enterococcus faecalis (83.25%) and against Candida tropicalis (77.03%) as compared to reference antibiotics.

UNASSIGNED

Data obtained from this study demonstrate that D. glaucum possesses significant antioxidant, cytotoxic, and antimicrobial activities which could be ascribed to its flavonoidal content.

CONCLUSIONS

Dipterygium glaucum Decne. herb is one of the common traditional plants with multiple medicinal uses in KSAFive flvonidal glycosides were isolated and elucidatedThis study demonstrated that D. glaucum possesses significant antioxidant, cytotoxic, and antimicrobial activities. Abbreviations used: KSA: Kingdom of Saudi Arabia; TLC: Thin Layer Chromatography; DPPH: 2,2`-diphenyl-1-picrylhydrazyl; EC50: Half maximal effective concentration; IC50: Half maximal inhibitory concentration; DMSO: dimethyl sulfoxide; NMR: Nuclear Magnetic Resonance; ESIMS: Electrospray ionization mass spectrometry; MeOH: Methyl alcohol.

The enzyme 17beta-hydroxysteroid dehydrogenase type 1 (17beta-HSD1) has become an important drug target for breast cancer because it catalyzes the interconversion of estrone to the biologically more potent estradiol which also plays a crucial role in the etiology of breast cancer. Patients with an increased expression of the 17beta-HSD1 gene have a significantly worse outcome than patients without. Inhibitors for 17beta-HSD1 are therefore included in therapy development. Here we have studied binding of 17beta-HSD1 to substrates and a number of inhibitors using NMR spectroscopy. Ligand observed NMR spectra show a strong pH dependence for the phytoestrogens luteolin and apigenin but not for the natural ligands estradiol and estrone. Moreover, NMR competition experiments show that the phytoestrogens do not replace the estrogens despite their similar inhibition levels in the in vitro assay. These results strongly support an additional 17beta-HSD1 binding site for phytoestrogens which is neither the substrate nor the co-factor binding site. Docking experiments suggest the dimer interface as a possible location. An additional binding site for the phytoestrogens may open new opportunities for the design of inhibitors, not only for 17beta-HSD1, but also for other family members of the short chain dehydrogenases.

Global market of herbs has been struggling with food adulteration issues. A number of assays have been developed to aid the detection of the tampered samples and ensure high quality of the marketed products. However, herbs are marketed not only for their culinary applications but also as remedies due to high levels of biologically active constituents. Nevertheless, there is no information in the literature about the influence of herbs adulteration on the biological activity of the final product. Current study aims at assessing the influence of oregano adulteration on its in-vitro estrogen-like activity. High responses in a mammalian reporter gene assay have been detected in pure and adulterated samples, translating to 21-7409 ng of 17β-estradiol equivalents per gram of oregano. The origin of those responses was assessed by combining fractionation and UHPLC-HRMS. Three flavones were proposed as the most active extract constituents i.e. luteolin-glucoside, luteolin- and apigenin-glucuronides all of which have been previously identified in other herbal extracts with estrogenic activity. This study underlines challenges of biological activity assessment in complex herbal extracts as well as the need for further assessment of such supplement administrations in the case of postmenopausal women and breast cancer patients undergoing hormone therapy.

Parkinsonia aculeata L. growing in Saudi Arabia was investigated for its phytochemical profile, antioxidant, and cytotoxic properties. UPLC-ESI-MS/MS was employed as a powerful technique for the characterization of secondary metabolites from a hydroalcoholic extract, dichloromethane, and ethyl acetate fractions of P. aculeata L. aerial parts. Sixty-nine compounds (flavonoids, anthocyanins, phenolics and fatty acids) were detected and characterized; flavonoids were the abundant components in the analyzed samples. The dichloromethane fraction was rich in phenolics as vanillic acid hexoside, flavonols as 3,7-dimthylquercetin, and flavones as 3'-hydroxymelanettin. However, the ethyl acetate fraction was rich in flavonoid-C-glycosides as luteolin-8-C-β-D-glucoside (orientin) and apigenin-8-C-glucoside (vitexin), flavonoid- O, C-diglycosides such as luteolin 7-O-[6''-dihydrogalloyl]-glucosyl-8-C-pentosyl-(1 → 2)-glucoside and 2''-O-rhamnosyl isoorientin. These compounds were identified for the first time in dichloromethane and ethyl acetate fractions of Saudi P. aculeata L. Additionally, all the samples were assessed for antioxidant activity using DPPH radical scavenging method and for cytotoxic activity through MTT assay. Accordingly, the most active fraction was the ethyl acetate which showed the highest antioxidant activity (SC₅₀ = 57.4 ± 1.2 μg/mL) compared with the positive control, ascorbic acid (SC₅₀ = 12.4 ± 0.5 μg/mL) and moderate cytotoxicity against HepG-2 (hepatocellular carcinoma) and MCF-7 (breast carcinoma) cell lines with IC₅₀ = 56.9 ± 3.1 and 95.8 ± 3.8 μg/mL, respectively compared with cisplatin (IC₅₀ = 3.67 ± 0.22 and 5.71 ± 0.57 μg/mL, respectively for both cell lines). The antioxidant and cytotoxic activities may be attributed to the presence of high percentage of phenolic compounds and hydroxylated flavonoids detected in ethyl acetate fraction using UPLS-ESI-MS/MS.

Keywords: Antioxidant; Cytotoxicity; Fabaceae; Parkinsonia aculeata; UPLC-ESI-MS/MS.

Investigation of Platycladus orientalis yielded five flavonoids, including aglycone flavone 1 (apigenin), flavone glycoside 2 (apigenin 7-O-β-D-glucopyranoside), new gernaylated flavone glycoside 3 (apigenin 8-gernayl-4'-O-α-gluco pyranoside) and two new pernylated flavonoid glycosides 4 & 5 (apigenin 8-pernyl-4'-glucopyranosyl-7-O-α-glucopyranoside and apigenin 5-pernyl-7-glucopyranosyl-4'-O-β-D-glucopyranoside). Their structures were elucidated on the basis of spectroscopic evidence. The cytotoxicity of compounds 1-5 were tested against Lung adenocarcinoma (A549), human hepatocellular liver carcinoma (HepG2), human breast carcinoma (MCF-7) cell lines and mouse fibroblast cell line NIH/3T3 as normal cells. This assay gave spot on structure activity relationship which, showed that cytotoxicity of compounds (1) and (2) against three cell lines was weak as IC₅₀ > 15. Compounds (4) and (5) had moderate cytotoxic and no toxic effect on normal cell. Compound (3) showed high cytotoxic activity against tested three cell lines with no toxic effect of normal cells. [Formula: see text].

Background: Saffron or stigmas of Crocus sativus L. is one of the most valuable food products with interesting health-promoting properties. C. sativus has been widely used as a coloring and flavoring agent. Stigmas secondary metabolites showed potent cytotoxic effects in previous reports.

Methods: The present study investigated the chemical composition and the cytotoxic effect of Ukrainian saffron crude extracts and individual compounds against melanoma IGR39, triple-negative breast cancer MDA-MB-231, and glioblastoma U-87 cell lines in vitro using MTT assay. Several bioactivity in vitro assays were performed. The chemical profile of the water and hydroethanolic (70%, v/v) crude extracts of saffron stigmas was elucidated by HPLC-DAD analysis.

Results: Seven compounds were identified including crocin, picrocrocin, safranal, rutin, apigenin, caffeic acid, ferulic acid. Crocin, picrocrocin, safranal, rutin, and apigenin were the major active constituents of Ukrainian C. sativus stigmas. The hydroethanolic extract significantly reduced the viability of MDA-MB-231 and IGR39 cells and the effect was more potent in comparison with the water extract. However, the water extract was almost 5.6 times more active against the U-87 cell line (EC₅₀ of the water extract against U-87 was 0.15 ± 0.02 mg/mL, and EC₅₀ of the hydroethanolic extract was 0.83 ± 0.03 mg/mL). The pure compounds, apigenin, and caffeic acid also showed high cytotoxic activity against breast cancer, melanoma, and glioblastoma cell lines. The screening of the biological activities of stigmas water extract (up to 100 μg/mL) including anti-allergic, anti-virus, anti-neuraminidase, and anti-inflammatory effects revealed its inhibitory activity against neuraminidase enzyme by 41%.

Conclusions: The presented results revealed the qualitative and quantitative chemical composition and biological activity of Crocus sativus stigmas from Ukraine as a source of natural anticancer and neuraminidase inhibitory agents. The results of the extracts' bioactivity suggested future potential applications of saffron as a natural remedy against several cancers.

Keywords: Crocus sativus; Crude extract; Cytotoxic activity; HPLC; Stigmas.

Multistep chromatographic separations of the chloroform extract of the Turkish endemic plant <i>Psephellus pyrrhoblepharus</i> (Boiss.) Wagenitz (syn. <i>Centaurea pyrrhoblephara</i> Boiss.) resulted in the isolation of six guaianolid-type sesquiterpenes, chlorojanerin (<b>1</b>), 19-deoxychlorojanerin (<b>2</b>), 15-hydroxyjanerin (<b>3</b>), aguerin B (<b>4</b>), cynaropicrin (<b>5</b>), eleganin (<b>6</b>); three flavonoids, <em>apigenin</em>, 6-methoxyluteolin and jaceosidine; two glycosides, benzyl-1-<i>O-</i>β-d-glucoside and 3(<i>Z</i>)-hexenyl-1-<i>O-</i>β-d-glucoside; and the coumarin scopoletin. The structures were established by the interpretation of their ESI-MS and 1D and 2D NMR data including ¹H-NMR, JMOD, ¹H,¹H-COSY, HSQC, HMBC, and NOESY experiments. All compounds were isolated for the first time from <i>P. pyrrhoblepharus</i>. Compounds <b>1</b>-<b>6</b>, the isolated flavonoids and scopoletin were evaluated for their antiproliferative activities on human gynecological cancer cell lines (SiHa, HeLa, and MDA-MB-231 cells) using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Chlorojanerin (<b>1</b>), 19-deoxychlorojanerin (<b>2</b>), aguerin B (<b>4</b>), cynaropicrin (<b>5</b>), eleganin (<b>6</b>) were shown to have noteworthy effects on all of the tested cell lines, while <em>apigenin</em>, jaceosidine, and 6-methoxyluteolin were moderately active on HeLa cells. The highest activities were demonstrated by the chlorine-containing derivatives chlorojanerin (<b>1</b>) and 19-deoxychlorojanerin (<b>2</b>) with IC₅₀ values of 2.21 and 2.88 µM, respectively, against the triple negative <em>breast</em> cancer model MDA-MB-231 cells.