2-4-3--5--tetrahydroxystilbene and Breast-Neoplasms

Dysregulation of epidermal growth factor receptor (EGFR)/human epidermal growth factor-2 (HER2) family is a hallmark of aggressive breast cancer. Small-molecule tyrosine kinase inhibitors are among the most effective cancer targeted treatments. (-)-Oleocanthal (OC) is a naturally occurring phenolic secoiridoid lead from extra-virgin olive oil with documented anti-cancer activities via targeting mesenchymal epithelial transition factor (c-Met). Dysregulation of c-Met promotes aggressiveness to breast cancer-targeted therapies. Lapatinib (LP) is an FDA-approved dual EGFR/HER2 inhibitor for HER2-amplified breast cancer. HER2-Positive tumor cells can escape targeted therapies like LP effects by overexpressing c-Met. Combined OC-LP treatment is hypothesized to be mechanistically synergistic against HER2-overexpressing breast cancer. Combined sub-effective treatments of OC-LP resulted in synergistic anti-proliferative effects against the HER2-positive BT-474 and SK-BR-3 breast cancer cell lines, compared to OC or LP monotherapy. Antibody array and Western blot analysis showed that combined OC-LP treatment significantly inhibited EGFR, HER2, and c-Met receptor activation, as well as multiple downstream signaling proteins, compared to individual OC or LP treatment. OC-LP Combination significantly inhibited invasion and migration of breast cancer cells through reduced activation of focal adhesion kinase (FAK) and paxillin. Combined treatment of OC-10 mg/kg with LP-12.5 mg/kg suppressed more than 90% of BT-474 tumor cells growth in a nude mouse xenograft model, compared to individual OC or LP treatment. Activated c-Met, EGFR, HER2, and protein kinase B (AKT) were significantly suppressed in combination-treated mice tumors, compared to OC or LP monotherapy. This study reveals the OC future potential as combination therapy to sensitize HER2-overexpressing breast cancers and significantly reduce required doses of targeted HER family therapeutics.

Topics: Aldehydes; Animals; Antineoplastic Agents; Breast Neoplasms; Cell Line, Tumor; Cyclopentane Monoterpenes; Drug Therapy, Combination; Epithelial-Mesenchymal Transition; ErbB Receptors; Female; Humans; Lapatinib; Mice; Phenols; Receptor, ErbB-2

Epidemiological and clinical studies compellingly documented the ability of Mediterranean diet rich in extra-virgin olive oil (EVOO) to reduce breast and colon cancers incidence, cardiovascular diseases, and aging cognitive functions decline. (-)-Oleocanthal (OC) and other EVOO phenolics gain progressive research attention due to their documented biological effects against cancer, inflammations, and Alzheimer's disease. There is no simple, reliable, and cost-effective isolation protocol for EVOO phenolics, which hinder their therapeutic applications. This study develops novel methods to isolate OC and other EVOO phenolics. This includes the use of ultra-freezing to eliminate most EVOO fats and the successful water capacity to efficiently extract OC and EVOO phenolics as self-emulsified nano-emulsion. Subsequent resin entrapment and size exclusion chromatography afforded individual EVOO phenolics in high purity. OC in vitro and in vivo oral anti-breast cancer (BC) activities validated its lead candidacy. Effective isolation of EVOO phenolics provided in this study will facilitate future preclinical and clinical investigations and stimulate the therapeutic development of these important bioactive natural products.

Topics: Aldehydes; Animals; Breast Neoplasms; Cell Line; Cell Line, Tumor; Cyclopentane Monoterpenes; Emulsions; Female; Humans; Liquid-Liquid Extraction; MCF-7 Cells; Mice; Mice, Nude; Olive Oil; Phenols

Topics: Aldehydes; Antineoplastic Agents; Breast Neoplasms; Cell Line, Tumor; Cell Proliferation; Cyclopentane Monoterpenes; Drug Synergism; Gene Expression Regulation, Neoplastic; Humans; Molecular Docking Simulation; Olive Oil; Phenols; Protein Conformation; Receptors, Estrogen; Tamoxifen; Xenograft Model Antitumor Assays

Fungi of the genus Penicillium produce unique and chemically diverse biologically active secondary metabolites, including indole alkaloids. The role of dysregulated hepatocyte growth factor (HGF) and its receptor, c-Met, in the development and progression of breast carcinoma is documented. The goal of this work is to explore the chemistry and bioactivity of the secondary metabolites of the endophytic Penicillium chrysogenum cultured from the leaf of the olive tree Olea europea, collected in its natural habitat in Egypt. This fungal extract showed good inhibitory activities against the proliferation and migration of several human breast cancer lines. The CH2Cl2 extract of P. chrysogenum mycelia was subjected to bioguided chromatographic separation to afford three known indole alkaloids; meleagrin (1), roquefortine C (2) and DHTD (3). Meleagrin inhibited the growth of the human breast cancer cell lines MDA-MB-231, MDA-468, BT-474, SK BR-3, MCF7 and MCF7-dox, while similar treatment doses were found to have no effect on the growth and viability of the non-tumorigenic human mammary epithelial cells MCF10A. Meleagrin also showed excellent ATP competitive c-Met inhibitory activity in Z-Lyte assay, which was further confirmed via molecular docking studies and Western blot analysis. In addition, meleagrin treatment caused a dose-dependent inhibition of HGF-induced cell migration, and invasion of breast cancer cell lines. Meleagrin treatment potently suppressed the invasive triple negative breast tumor cell growth in an orthotopic athymic nude mice model, promoting this unique natural product from hit to a lead rank. The indole alkaloid meleagrin is a novel lead c-Met inhibitory entity useful for the control of c-Met-dependent metastatic and invasive breast malignancies.

Topics: Animals; Antineoplastic Agents; Breast Neoplasms; Cell Line; Cell Movement; Cell Proliferation; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; Epithelial Cells; Female; Humans; Indole Alkaloids; Mammary Neoplasms, Experimental; Mice; Mice, Nude; Models, Molecular; Molecular Structure; Neoplasm Invasiveness; Olea; Ovomucin; Penicillium chrysogenum; Proto-Oncogene Proteins c-met; Structure-Activity Relationship

The established anticancer and neuroprotective properties of oleocanthal combined with the reported role of mammalian target of rapamycin (mTOR) in cancer and Alzheimer's disease development encouraged us to examine the possibility that oleocanthal inhibits mTOR. To validate this hypothesis, we docked oleocanthal into the adenosine triphosphate binding pocket of a close mTOR protein homologue, namely, PI3K-γ. Apparently, oleocanthal shared nine out of ten critical binding interactions with a potent dual PIK3-γ/mTOR natural inhibitor. Subsequent experimental validation indicated that oleocanthal indeed inhibited the enzymatic activity of mTOR with an IC50 value of 708 nM. Oleocanthal inhibits the growth of several breast cancer cell lines at low micromolar concentration in a dose-dependent manner. Oleocanthal treatment caused a marked downregulation of phosphorylated mTOR in metastatic breast cancer cell line (MDA-MB-231). These results strongly indicate that mTOR inhibition is at least one of the factors of the reported anticancer and neuroprotective properties of oleocanthal.

Topics: Aldehydes; Animals; Breast Neoplasms; Cyclopentane Monoterpenes; Female; Humans; Models, Molecular; Olive Oil; Phenols; Phosphatidylinositol 3-Kinases; Phosphorylation; Sirolimus; TOR Serine-Threonine Kinases

Dysregulation of the Hepatocyte growth factor (HGF)/c-Met signaling axis upregulates diverse tumor cell functions, including cell proliferation, survival, scattering and motility, epithelial-to-mesenchymal transition (EMT), angiogenesis, invasion, and metastasis. (-)-Oleocanthal is a naturally occurring secoiridoid from extra-virgin olive oil, which showed antiproliferative and antimigratory activity against different cancer cell lines. The aim of this study was to characterize the intracellular mechanisms involved in mediating the anticancer effects of (-)-oleocanthal treatment and the potential involvement of c-Met receptor signaling components in breast cancer. Results showed that (-)-oleocanthal inhibits the growth of human breast cancer cell lines MDA-MB-231, MCF-7 and BT-474 while similar treatment doses were found to have no effect on normal human MCF10A cell growth. In addition, (-)-oleocanthal treatment caused a dose-dependent inhibition of HGF-induced cell migration, invasion and G1/S cell cycle progression in breast cancer cell lines. Moreover, (-)-oleocanthal treatment effects were found to be mediated via inhibition of HGF-induced c-Met activation and its downstream mitogenic signaling pathways. This growth inhibitory effect is associated with blockade of EMT and reduction in cellular motility. Further results from in vivo studies showed that (-)-oleocanthal treatment suppressed tumor cell growth in an orthotopic model of breast cancer in athymic nude mice. Collectively, the findings of this study suggest that (-)-oleocanthal is a promising dietary supplement lead with potential for therapeutic use to control malignancies with aberrant c-Met activity.

Topics: Aldehydes; Animals; Antineoplastic Agents; Apoptosis; Breast Neoplasms; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Cyclopentane Monoterpenes; Epithelial-Mesenchymal Transition; Female; Hepatocyte Growth Factor; Humans; Intracellular Space; Mice; Mitogen-Activated Protein Kinases; Neoplasm Invasiveness; Olea; Phenols; Phosphorylation; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-akt; Proto-Oncogene Proteins c-met; Signal Transduction; Xenograft Model Antitumor Assays

(-)-Oleocanthal (1) and ligstroside aglycone (2) are common bioactive olive oil secoiridoids. Secoiridoid 1 has been previously reported as a c-MET inhibitor. Chemically, (-)-oleocanthal is the elenolic acid ester of the common olive phenolic alcohol tyrosol. Therefore, several analogues (4-13) were synthesized by esterification and carbamoylation of tyrosol using diverse phenolic naturally occurring in olive and heterocyclic acids as elenolic acid bioisosteres to assess the effect of replacing the acid moiety of (-)-oleocanthal. Their c-MET inhibitory activity as well as their antiproliferative, antimigratory, and anti-invasive activities against the highly metastatic human breast cancer cell line MDA-MB231 has been assessed. Ligstroside aglycone (2) showed the best antimigratory activity. Generally, tyrosol esters showed better activities versus carbamate analogues. Tyrosol sinapate (5) showed the best c-MET phosphorylation inhibitory activity in Z'-LYTE kinase assay. Both 1 and 5 competitively inhibited the ATP binding into its pocket in the c-MET catalytic domain. Compound 5 showed selective activities against tumor cells without toxicity to the non-tumorigenic human breast MCF10A epithelial cell line. Tyrosol esters with a phenolic acid containing hydrogen bond donor and/or acceptor groups at the para-position have better anticancer and c-MET inhibitory activities. Olive oil secoiridoids are excellent scaffolds for the design of novel c-MET inhibitors.

Topics: Antineoplastic Agents; Breast; Breast Neoplasms; Cell Line, Tumor; Cell Movement; Cell Proliferation; Female; Humans; Iridoids; Neoplasm Metastasis; Olea; Proto-Oncogene Proteins c-met; Wound Healing

The proto-oncogene receptor tyrosine kinase c-Met encodes the high-affinity receptor for hepatocyte growth factor (HGF). Dysregulation of the HGF-c-Met pathway plays a significant oncogenic role in many tumors. Overexpression of c-Met is a prognostic indicator for some transitional cell carcinomas. Extra-virgin olive oil (EVOO) provides a variety of minor phenolic compounds with beneficial properties. (-)-Oleocanthal (1) is a naturally occurring minor secoiridoid isolated from EVOO, which showed potent anti-inflammatory activity via its ability to inhibit COX-1 and COX-2. It altered the structure of neurotoxic proteins believed to contribute to the debilitating effects of Alzheimer's disease. Computer-Assisted Molecular Design (CAMD) identified 1 as a potential virtual c-Met inhibitor hit. Oleocanthal inhibited the proliferation, migration, and invasion of the epithelial human breast and prostate cancer cell lines MCF7, MDA-MB-231, and PC-3, respectively, with an IC (50) range of 10-20 µM, and demonstrated anti-angiogenic activity via downregulating the expression of the microvessel density marker CD31 in endothelial colony forming cells with an IC (50) of 4.4 µM. It inhibited the phosphorylation of c-Met kinase IN VITRO in the Z'-LYTE™ assay, with an IC (50) value of 4.8 µM. (-)-Oleocanthal and EVOO can have potential therapeutic use for the control of c-Met-dependent malignancies.

Topics: Adenosine Triphosphate; Aldehydes; Angiogenesis Inhibitors; Antineoplastic Agents, Phytogenic; Binding Sites; Breast Neoplasms; Cell Line, Tumor; Cell Movement; Cell Proliferation; Cyclopentane Monoterpenes; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; Female; Humans; Inhibitory Concentration 50; Male; Models, Molecular; Neoplasm Invasiveness; Neovascularization, Pathologic; Olive Oil; Phenols; Plant Oils; Platelet Endothelial Cell Adhesion Molecule-1; Prostatic Neoplasms; Protein Kinases; Proto-Oncogene Mas; Proto-Oncogene Proteins c-met