mangostin and Colorectal-Neoplasms

α-Mangostin (aMan) and Paeonol (Pae) have shown anticancer and anti-inflammatory properties. However, these two natural compounds have no clinical value because of their low solubility and low membrane permeability. In this study, we screened chemically synthesized derivatives from these two natural compounds as potential novel chemicals that increase cancer cell cytotoxicity over nontransformed human cells. We found that two derivative compounds, named α-Mangostin-1 (aMan1) and Paeonol-1 (Pae1) more efficiently and more specifically induced cytotoxicity in HCT116, HT29, and SW48 colorectal cancer cell lines than the parental compounds. Both aMan1 and Pae1 arrested HCT116 cells in the G

Topics: Acetophenones; Anti-Inflammatory Agents; Antineoplastic Agents; Cell Proliferation; Colorectal Neoplasms; Humans; Protein Kinase Inhibitors; Xanthones

Despite advances in chemotherapies and targeted drugs, colorectal cancer (CRC) remains challenging to treat due to drug resistance. Emerging evidence indicates that cancer-associated fibroblasts (CAFs) facilitate the generation of cancer stem-like cells (CSCs) and drug resistance. Glycogen synthase kinase-3 (GSK) associated signaling pathways have been implicated in the generation of CSCs and represent a target for therapeutics development.. Gamma-mangostin (gMG) isolated from Garcinia mangostana was evaluated for its ability to downregulate GSK3β-associated signaling in CRC cells and overcome CAF-induced 5-fluorouracil resistance and CSC generation.. Bioinformatics analysis, in silico molecular docking, in vitro assays, including cell viability tests, colony- and tumor sphere-formation assays, transwell migration assays, ELISA, SDS-PAGE, Western blotting, miR expression, qPCR, and flow cytometry, as well as in vivo mouse xenograft models were used to evaluate the antitumor effects of gMG.. Bioinformatics analyses indicated that GSK3β/CDK6/β-catenin mRNA signature was significantly higher in colon cancer patients. Additional algorithms predicted a higher miR-26b level was associated with significantly higher survival in CRC patients and GSK3β and CDK6 as targets of miR-26b-5p. To validate these findings in vitro, we showed that CAF-cocultured CRC cells expressed an increased expression of GSK3β, β-catenin, CDK6, and NF-κB. Therapeutically, we demonstrated that gMG treatment suppressed GSK3β-associated signaling pathways while concomitantly increased the miR-26b-5p level. Using a xenograft mouse model of CAFs cocultured HCT116 tumorspheres, we showed that gMG treatment reduced tumor growth and overcame CAF-induced 5-fluorouracil resistance.. Pharmacological intervention with gMG suppressed CRC carcinogenesis and stemness via downregulating GSK3/β-catenin/CDK6 and upregulating the miR-26b-5p tumor suppressor. Thus, gMG represents a potential new CRC therapeutic agent and warrants further investigation.

Topics: Animals; beta Catenin; Carcinogenesis; Cell Line, Tumor; Cell Proliferation; Colon; Colorectal Neoplasms; Cyclin-Dependent Kinase 6; Garcinia mangostana; Gene Expression Regulation, Neoplastic; Glycogen Synthase Kinase 3 beta; Humans; Mice; MicroRNAs; Molecular Docking Simulation; Wnt Signaling Pathway; Xanthones

Colorectal cancer (CRC) is the fourth leading cause of cancer-related mortality. Recent studies have stated that Notch signalling is highly activated in cancer stem cells (CSCs) and plays an important role in the development and progression of CRC. Like normal colorectal epithelium, CRCs are organized hierarchically and include populations of CSCs. In order to enhance the biological activity of α-mangostin, we formulated α-mangostin-encapsulated PLGA nanoparticles (Mang-NPs) and examined the molecular mechanisms by which Mang-NPs inhibit CRC cell viability, colony formation, epithelial-mesenchymal transition (EMT) and induce apoptosis. Mang-NPs inhibited cell viability, colony formation and induced apoptosis. Mang-NPs also inhibited EMT by up-regulating E-cadherin and inhibiting N-cadherin and transcription factors Snail, Slug and Zeb1. As dysregulated signalling through the Notch receptors promotes oncogenesis, we measured the effects of Mang-NPs on Notch pathway. Mang-NPs inhibited Notch signalling by suppressing the expression of Notch receptors (Notch1 and Notch2), their ligands (Jagged 1 and DLL4), γ-secretase complex protein (Nicastrin) and downstream target (Hes-1). Notch receptor signalling regulates cell fate determination in stem cell population. Finally, Mang-NPs inhibited the self-renewal capacity of CSCs, stem cell markers (CD133, CD44, Musashi and LGR5) and pluripotency maintaining factors (Oct4, Sox-2, KLF-4, c-Myc and Nanog). Overall, our data suggest that Mang-NPs can inhibit CRC growth, EMT and CSCs' population by suppressing Notch pathway and its target. Therefore, Mang-NPs can be used for the treatment and prevention of CRC.

Topics: Apoptosis; Biomarkers, Tumor; Cell Line, Tumor; Cell Movement; Cell Proliferation; Cell Survival; Colorectal Neoplasms; Endocytosis; Epithelial Cells; Epithelial-Mesenchymal Transition; Humans; Nanoparticles; Neoplasm Invasiveness; Neoplastic Stem Cells; Pluripotent Stem Cells; Polylactic Acid-Polyglycolic Acid Copolymer; Receptors, Notch; Signal Transduction; Spheroids, Cellular; Tumor Stem Cell Assay; Xanthones

Despite the progress in colon cancer treatment, relapse is still a major obstacle. Hence, new drugs or drug combinations are required in the battle against colon cancer. α-Mangostin and betulinic acid (BA) are cytotoxic compounds that work by inducing the mitochondrial apoptosis pathway, and cisplatin is one of the most potent broad spectrum anti-tumor agents. This study aims to investigate the enhancement of BA cytotoxicity by α-mangostin, and the cytoprotection effect of α-mangostin and BA on cisplatin-induced cytotoxicity on HCT 116 human colorectal carcinoma cells. Cytotoxicity was investigated by the XTT cell proliferation test, and the apoptotic effects were investigated on early and late markers including caspases-3/7, mitochondrial membrane potential, cytoplasmic shrinkage, and chromatin condensation. The effect of α-mangostin on four signalling pathways was also investigated by the luciferase assay. α-Mangostin and BA were more cytotoxic to the colon cancer cells than to the normal colonic cells, and both compounds showed a cytoprotective effect against cisplatin-induced cytotoxicity. On the other hand, α-mangostin enhanced the cytotoxic and apoptotic effects of BA. Combination therapy hits multiple targets, which may improve the overall response to the treatment, and may reduce the likelihood of developing drug resistance by the tumor cells. Therefore, α-mangostin and BA may provide a novel combination for the treatment of colorectal carcinoma. The cytoprotective effect of the compounds against cisplatin-induced cytotoxicity may find applications as chemopreventive agents against carcinogens, irradiation and oxidative stress, or to neutralize cisplatin side effects.

Topics: Antineoplastic Agents; Apoptosis; Betulinic Acid; Caspase 3; Caspase 7; Cell Proliferation; Cell Shape; Cell Survival; Chromatin; Cisplatin; Colorectal Neoplasms; Cytoprotection; Drug Synergism; HCT116 Cells; Humans; Inhibitory Concentration 50; Membrane Potential, Mitochondrial; Pentacyclic Triterpenes; Signal Transduction; Triterpenes; Xanthones

alpha-Mangostin, a xanthone from the pericarps of mangosteen (Garcinia mangostana Linn.), was evaluated for in vitro cytotoxicity against human colon cancer DLD-1 cells. The number of viable cells was consistently decreased by the treatment with alpha-mangostin at more than 20 microM. The cytotoxic effect of 20 microM alpha-mangostin was found to be mainly due to apoptosis, as indicated by morphological findings. Western blotting, the results of an apoptosis inhibition assay using caspase inhibitors, and the examination of caspase activity did not demonstrate the activation of any of the caspases tested. However, endonuclease-G released from mitochondria with the decreased mitochondrial membrane potential was shown. The levels of phospho-Erk1/2 were increased in the early phase until 1h after the start of treatment and thereafter decreased, and increased again in the late phase. On the other hand, the level of phospho-Akt was sharply reduced with the process of apoptosis after 6h of treatment. Interestingly, the level of microRNA-143, which negatively regulates Erk5 at translation, gradually increased until 24h following the start of treatment. We also examined the synergistic growth suppression in DLD-1 cells by the combined treatment of the cells with alpha-mangostin and 5-FU which is one of the most effective chemotherapeutic agents for colorectal adenocarcinoma. The co-treatment with alpha-mangostin and 5-FU, both at 2.5 microM, augmented growth inhibition compared with the treatment with 5 microM of alpha-mangostin or 5 microM 5-FU alone. These findings indicate unique mechanisms of alpha-mangostin-induced apoptosis and its action as an effective chemosensitizer.

Topics: Apoptosis; Caspases; Cell Line, Tumor; Colorectal Neoplasms; Endodeoxyribonucleases; Fluorouracil; Humans; MicroRNAs; Mitochondria; Mitogen-Activated Protein Kinases; Proto-Oncogene Proteins c-akt; Xanthones