Synthesis and cytotoxic evaluation of novel 7-O-modified genistein derivatives

Research Progress on Structural Modification of Effective Antitumor Active Ingredients in Licorice

Licorice, a widely used traditional Chinese medicine, contains more than 300 flavonoids and more than 20 triterpenoids, which have potential medicinal value and can prevent the growth of tumor cells by blocking the cell cycle, affecting the regulation of the apoptosis gene of tumor cells, and inhibiting tumor cell angiogenesis. However, many of the compounds in licorice still have the drawbacks of poor solubility, significant toxic side effects, and low antitumor activity. This article reviews the structural modification of effective antitumor active ingredients in licorice, thus providing a theoretical basis for further investigation of licorice and the development of new antitumor drugs.

Genistein: Therapeutic and Preventive Effects, Mechanisms, and Clinical Application in Digestive Tract Tumor

Genistein is one of the numerous recognized isoflavones that may be found in a variety of soybeans and soy products, including tofu and tofu products. The chemical name for genistein is 4', 5, 7-trihydroxyisoflavone, and it is found in plants. In recent years, the scientific world has become more interested in genistein because of its possible therapeutic effects on many forms of cancer. It has been widely investigated for its anticancer properties. The discovery of genistein's mechanism of action indicates its potential for apoptosis induction and cell cycle arrest in gastrointestinal cancer, especially gastric and colorectal cancer. Genistein's pharmacological activities as determined by the experimental studies presented in this review lend support to its use in the treatment of gastrointestinal cancer; however, additional research is needed in the future to determine its efficacy, safety, and the potential for using nanotechnology to increase bioavailability and therapeutic efficacy.

Synthesis and Bio-evaluation of 2-Alkyl Substituted Fluorinated Genistein Analogues Against Breast Cancer

BACKGROUND

Breast cancer is the leading cause of cancer death in women. The current methods of chemotherapy for breast cancer generally have strong adverse reactions and drug resistance. Therefore, the discovery of novel anti-breast cancer lead compounds is urgently needed.

OBJECTIVE

Design and synthesize a series of 2-alkyl substituted fluorinated genistein analogues and evaluate their anti-breast cancer activity.

METHODS

Target compounds were obtained in a multistep reaction synthesis. The anti-tumor activity of compounds I-1~I-35 were evaluated with MCF-7, MDA-MB-231, MDA-MB-435, and MCF-10A cell lines in vitro, with tamoxifen as the positive control. Molecular docking was used to study the interaction between the synthesized compounds and PI3K-gamma.

RESULTS

A series of 2-alkyl substituted fluorinated genistein analogues were designed, synthesized and screened for their bioactivity. Most of the compounds displayed better selectivity toward breast cancer cell lines as compared with tamoxifen. Among these analogues, I-2, I-3, I-4, I-9, I-15 and I-17 have the strongest selective inhibition of breast cancer cells. Compounds I-10, I-13, I-15, I-17 and I-33 were found to have significant inhibitory effects on breast cancer cells. Molecular docking studies have shown that these compounds may act as PI3Kγ inhibitors and may further exhibit anti-breast cancer effects.

CONCLUSION

Most of the newly synthesized compounds could highly selectively inhibit breast cancer cell lines. The experimental results indicate that the synthesized analogs may also have obvious selective inhibitory effects on other malignant proliferation cancer cells.

Genistein Loaded Nanofibers Protect Spinal Cord Tissue Following Experimental Injury in Rats

Innovative drug-delivery systems offer a unique approach to effectively provide therapeutic drug dose over the needed time to achieve better tissue protection and enhanced recovery. The hypothesis of the current study was to test the antioxidant and anti-inflammatory effects of genistein and nanofibers on the spinal cord tissue following experimental spinal cord injury (SCI). Rats were treated post SCI with genistein that is loaded on chitosan/polyvinyl alcohol (CS/PVA) nanofibers as an implantable drug-delivery system. SCI caused marked oxidative damage and inflammation, as is evident by the reduction in the super oxide dismutase (SOD) activity and the level of interleukin-10 (IL-10) in injured spinal cord tissue, as well as the significant increase in the levels of nitric oxide (NO), malondialdehyde (MDA), and tumor necrosis factor-alpha (TNF-α). Treatment of rats post SCI with genistein and CS/PVA nanofibers improved most of the above-mentioned biochemical parameters and shifted them toward the control group values. Genistein induced an increase in the activity of SOD and the level of IL-10, while causing a decrease in NO, MDA, and TNF-α in injured spinal cord tissue. Genistein and CS/PVA nanofibers provide a novel combination for treating inflammatory nervous tissue conditions, especially when combined as an implantable drug-delivery system.

Synthesis of Water-Soluble 7-O-Carboxymethyl-Genistein

A three-step synthesis from genistein of the water-soluble sodium salt of 7-O-carboxymethyl-genistein is described. Base-catalysed reaction of genistein with t-butyl bromoacetate gave 7-O-(carbo-t-butoxy)methyl-genistein, which was hydrolysed by aqueous acetic acid to 7-O-carboxymethyl-genistein and neutralised (NaHCO3) to give the target compound. The carboxylate group enhanced the water-solubility of genistein more than a thousand-fold and the new derivate will be useful as a candidate compound in pharmacological and clinical chemistry studies of isoflavones.

Genistein and cancer: current status, challenges, and future directions

Primary prevention through lifestyle interventions is a cost-effective alternative for preventing a large burden of chronic and degenerative diseases, including cancer, which is one of the leading causes of morbidity and mortality worldwide. In the past decade, epidemiologic and preclinical evidence suggested that polyphenolic phytochemicals present in many plant foods possess chemopreventive properties against several cancer forms. Thus, there has been increasing interest in the potential cancer chemopreventive agents obtained from natural sources, such as polyphenols, that may represent a new, affordable approach to curb the increasing burden of cancer throughout the world. Several epidemiologic studies showed a relation between a soy-rich diet and cancer prevention, which was attributed to the presence of a phenolic compound, genistein, present in soy-based foods. Genistein acts as a chemotherapeutic agent against different types of cancer, mainly by altering apoptosis, the cell cycle, and angiogenesis and inhibiting metastasis. Targeting caspases, B cell lymphoma 2 (Bcl-2)-associated X protein (Bax), Bcl-2, kinesin-like protein 20A (KIF20A), extracellular signal-regulated kinase 1/2 (ERK1/2), nuclear transcription factor κB (NF-κB), mitogen-activated protein kinase (MAPK), inhibitor of NF-κB (IκB), Wingless and integration 1 β-catenin (Wnt/β-catenin), and phosphoinositide 3 kinase/Akt (PI3K/Akt) signaling pathways may act as the molecular mechanisms of the anticancer, therapeutic effects of genistein. Genistein also shows synergistic behavior with well-known anticancer drugs, such as adriamycin, docetaxel, and tamoxifen, suggesting a potential role in combination therapy. This review critically analyzes the available literature on the therapeutic role of genistein on different types of cancer, focusing on its chemical features, plant food sources, bioavailability, and safety.

Synthesis and biological evaluation of apigenin derivatives as antibacterial and antiproliferative agents

Two series of apigenin [5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-chromen-4-one] derivatives, 3a–3j and 4a–4j, were synthesized. The apigenin and alkyl amines moieties of these compounds were separated by C₂ or C₃ spacers, respectively. The chemical structures of the apigenin derivatives were confirmed using ¹H-NMR, ¹³C-NMR, and electrospray ionization mass spectroscopy. The in vitro antibacterial and antiproliferative activities of all synthesized compounds were determined. Among the tested compounds, 4a–4j displayed significant antibacterial activity against the tested strains (Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa). Additionally, 4i showed the best inhibitory activity with minimum inhibitory concentrations of 1.95, 3.91, 3.91, and 3.91 μg/mL against S. aureus, B. subtilis, E. coli, and P. aeruginosa, respectively. The antiproliferative activity of the apigenin derivatives was evaluated by an MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] assay. We determined that 4a–4j displayed better growth inhibition activity against four human cancer cell lines, namely, human lung (A549), human cervical (HeLa), human hepatocellular liver (HepG2), and human breast (MCF-7) cancer cells, than the parent apigenin. Compound 4j was found to be the most active antiproliferative compound against the selected cancer cells. Structure-activity relationships were also discussed based on the obtained experimental data.

Natural product MDM2 inhibitors: anticancer activity and mechanisms of action

The mdm2 oncogene has recently been suggested to be a valuable target for cancer therapy and prevention. Overexpression of mdm2 is often seen in various human cancers and correlates with high-grade, late-stage, and more treatment-resistant tumors. The MDM2-p53 auto-regulatory loop has been extensively investigated and is an attractive cancer target, which indeed has been the main focus of anti-MDM2 drug discovery. Much effort has been expended in the development of small molecule MDM2 antagonists targeting the MDM2-p53 interaction, and a few of these have advanced into clinical trials. However, MDM2 exerts its oncogenic activity through both p53-dependent and -independent mechanisms. Recently, there is an increasing interest in identifying natural MDM2 inhibitors; some of them have been shown to decrease MDM2 expression and activity in vitro and in vivo. These identified natural MDM2 inhibitors include a plethora of diverse chemical frameworks, ranging from flavonoids, steroids, and sesquiterpenes to alkaloids. In addition to a brief review of synthetic MDM2 inhibitors, this review focuses on natural product MDM2 inhibitors, summarizing their biological activities in vitro and in vivo and the underlying molecular mechanisms of action, targeting MDM2 itself, regulators of MDM2, and/or the MDM2-p53 interaction. These MDM2 inhibitors can be used alone or in combination with conventional treatments, improving the prospects for cancer therapy and prevention. Their complex and unique molecular architectures may provide a stimulus for developing synthetic analogs in the future.

C-Glycosidic Genistein Conjugates and Their Antiproliferative Activity

This paper presents our attempt to investigate scopes and the limitations of olefin cross-metathesis (CM) reaction in the synthesis of complex C-glycosides of genistein and evaluation of their antiproliferative activities. Novel genistein glycoconjugates were synthesized with the utility of CM reaction initiated by first and second generation of Grubbs catalysts. The relative reactivity of utilized olefins, based on categories proposed by Grubbs, was estimated.In vitroexperiments in cancer cell lines showed that the selected derivatives (3aand3f) exhibited higher antiproliferative potential than the parent compound, genistein, and were able to block the cell cycle in the G2/M phase. The observed mechanism of action of C-glycosidic derivatives was similar to the activity of their O-glycosidic counterparts. These compounds were stable in culture medium. The obtained results show that our approach to genistein modification with application of cross-metathesis reaction allowed to obtain stable glycoconjugates with improved anticancer potential, compared to the parent isoflavone.

Genistein Derivatives Regioisomerically Substituted at 7-O- and 4′-O- Have Different Effect on the Cell Cycle

Our previous studies on antiproliferative properties of genistein derivatives substituted at C7 hydroxyl group of the ring A revealed some compounds with antimitotic properties. The aim of this work was to synthesize their analogues substituted at the 4′-position of the ring B in genistein and to define their antiproliferative mechanism of action in selected cancer cell linesin vitro. C4′-substituted glycoconjugates were obtained in a three-step procedure: (1) alkylation with anω-bromoester; (2) deacylation; (3) Ferrier-type rearrangement glycosylation with acylated glycals. Biological effects including antiproliferative effects of the compounds, cell cycle, DNA lesions (ATM activation, H2A.X phosphorylation, and micronuclei formation), and autophagy were studied in human cancer cell lines. Some of the tested derivatives potently inhibited cell proliferation. The presence of a substituent at the 4′-position of the ring B in genistein correlated to a p53-independent G1 cell-cycle arrest. The derivatives substituted at C4′ did not induce DNA lesions and appeared to be nongenotoxic. The tested compounds induced autophagy and caused remarkable decrease of cell volume.

Synthesis and Biological Evaluation of 7-O-Modified Formononetin Derivatives

Three series of novel formononetin derivatives were synthesized, in which formononetin and heterocyclic moieties were separated by 2-carbon, 3-carbon, and 4-carbon spacers. The chemical structures of these compounds were confirmed. All the derivatives were screened for antiproliferative activities against Jurkat cell line and HepG-2 cell line. In this paper, compounds prepared were also screened for their antibacterial activity of six bacterial strains. Compound 3b exihibited promising antibacterial activity against B. subtilis with minimal inhibitory concentration (MIC) value of 0.78 μg/mL, and compound 5e showed significant antiproliferative activities against Jurkat cell growth with IC50 of 1.35×10−4 μg/mL. The preliminary investigation of structure-activity relationships (SARs) was also discussed based on the obtained experimental data.

Effect of genistein-magnetic-nanoparticles on the growth and apoptosis of gastric cancer cell line SGC-7901

AIM: To observe the effects of different concentrations of genistein-magnetic-nanoparticles (GEN-M-NPs) on the growth and apoptosis of gastric cancer cell line SGC-7901.

METHODS: GEN-M-NPs were prepared by chemical co-precipitation. Morphology of GEN-M-NPs was observed under a transmission electron microscope. Encapsulating efficiency of genistein was determined by high-performance liquid chromatography. After SGC-7901 cells were treated with various concentrations of GEN-M-NPs and genistein, their anti-tumor effects were determined by methyl thiazolyl tetrazolium (MTT) assay. Apoptosis rate was quantified by flow cytometry and DNA fragmentation was evaluated by agarose gel electrophoresis.

RESULTS: GEN-M-NPs were round or elliptical in shape with a diameter of about 105 nm. Their encapsulating efficiency was about 10.3%. The proliferation of SGC-7901 cells in vitro was significantly inhibited by GEN-M-NPs in a time- and dose-dependent manner (P < 0.05). The release of GEN-M-NPs was slower than that of genistein (86.04% vs 67.11%, P < 0.05). After treatment with various concentrations of GEN-M-NPs for 72 h, the apoptosis rate for GEN-M-NPs and negative control groups was 5.62% ± 2.04% (10 μmol/L), 13.46% ± 2.02% (20 μmol/L), 26.40% ± 3.84% (40 μmol/L), 37.34% ± 4.68%(80 μmol/L), 49.43% ± 8.29% (100 μmol/L), and 2.60% ± 1.34% (control), respectively. Agarose gel electrophoresis showed typical apoptotic DNA ladders 24 h after treatment with 40 μmol/L GEN-M-NPs.

CONCLUSION: GEN-M-NPs can effectively inhibit the growth and apoptosis of SGC-7901 cells.

6,6′-Oxydichroman

The title compound, C₁₈H₁₈O₃, was synthesized from dichroman in concentrated sulfuric acid. The mol­ecule has a twofold axis passing through the central O atom. The dihedral angle between the two symmetry-related benzene rings is 63.6 (3)°. Weak C—H⋯π inter­actions are present in the structure.