Honokiol: a potent chemotherapy candidate for human colorectal carcinoma.

Cancer Institute, Second Affiliated Hospital of Zhejiang University, Hangzhou 310009, Zhejiang province, China.
World Journal of Gastroenterology (Impact Factor: 2.43). 01/2005; 10(23):3459-63.
Source: PubMed

ABSTRACT To investigate the anticancer activity of honokiol on RKO, a human colorectal carcinoma cell line in vitro and in vivo, and to evaluate its possible use in clinic.
In vitro anticancer activity of honokiol was demonstrated by its induction of apoptosis in tumor cells. We analyzed cell proliferation with MTT assay, cell cycle with flow cytosmeter, DNA fragment with electrophoresis on agarose gels. To test the mechanism of honokiol-induced apoptosis, Western blotting was used to investigate the factors involved in this process. The pharmacokinetics study of honokiol was tested by high phase liquid chromatography. In in vivo study, Balb/c nude mice were incubated with RKO cells. Honokiol was injected intraperitoneally every other day into tumor bearing Balb/c nude mice.
Our results showed that honokiol induced apoptosis of RKO cells in a time- and dose-dependent manner. At 5-10 microg/mL for 48 h, honokiol induced apoptosis through activating Caspase cascades. Pharmacokinetics study demonstrated that, honokiol could be absorbed quickly by intraperitoneal injection, and maintained in plasma for more than 10 h. In nude mice bearing RKO-incubated tumor, honokiol displayed anticancer activity by inhibiting tumor growth and prolonging the lifespan of tumor bearing mice.
With its few toxicity to normal cells and potent anticancer activity in vitro and in vivo, honokiol might be a potential chemotherapy candidate in treating human colorectal carcinoma.

1 Follower
  • [Show abstract] [Hide abstract]
    ABSTRACT: A main problem in oncology is the development of drug-resistance. Some plant-derived lignans are established in cancer therapy, e.g. the semisynthetic epipodophyllotoxins etoposide and teniposide. Their activity is, unfortunately, hampered by the ATP-binding cassette (ABC) efflux transporter,P-glycoprotein. Here, we investigated the bisphenolic honokiol derived from Magnolia officinalis. P-glycoprotein-overexpressing CEM/ADR5000 cells were not cross-resistant to honokiol, but MDA-MB-231BRCP cells transfected with another ABC-transporter, BCRP, revealed 3-fold resistance. Further drug resis-tance mechanisms analyzed study was the tumor suppressor TP53 and the epidermal growth factorreceptor (EGFR). HCT116 p53−/−did not reveal resistance to honokiol, and EGFR-transfected U87.MGEGFR cells were collateral sensitive compared to wild-type cells (degree of resistance: 0.34). To gain insight into possible modes of collateral sensitivity, we performed in silico molecular docking studies of honokiol to EGFR and EGFR-related downstream signal proteins. Honokiol bound with comparable binding energies to EGFR (−7.30 ± 0.01 kcal/mol) as the control drugs erlotinib (−7.50 ± 0.30 kcal/mol)and gefitinib (−8.30 ± 0.10 kcal/mol). Similar binding affinities of AKT, MEK1, MEK2, STAT3 and mTOR were calculated for honokiol (range from −9.0 ± 0.01 to 7.40 ± 0.01 kcal/mol) compared to corresponding control inhibitor compounds for these signal transducers. This indicates that collateral sensitivity of EGFR-transfectant cells towards honokiol may be due to binding to EGFR and downstream signal transducers. COMPARE and hierarchical cluster analyses of microarray-based transcriptomic mRNA expression data of 59 tumor cell lines revealed a specific gene expression profile predicting sensitivity or resistance towards honokiol.
    Phytomedicine: international journal of phytotherapy and phytopharmacology 10/2014; 21(12):1525–1533. DOI:10.1016/j.phymed.2014.07.011 · 2.88 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Honokiol, an active constituent of oriental medicinal herb Magnolia officinalis, caused Ca(2+) mobilization and apoptosis in different cancer cells. In vivo, honokiol crossed the blood-brain or -cerebrospinal fluid barrier, suggesting that it may be an effective drug for the treatment of brain tumors, including glioblastoma. This study examined the effect of honokiol on intracellular Ca(2+) concentration ([Ca(2+)]i) and apoptosis in DBTRG-05MG human glioblastoma cells. Honokiol concentration-dependently induced a [Ca(2+)]i rise. The signal was decreased partially by removal of extracellular Ca(2+). Honokiol-triggered [Ca(2+)]i rise was not suppressed by store-operated Ca(2+) channel blockers (nifedipine, econazole, SK&F96365) and the protein kinase C (PKC) activator phorbol 12-myristate 13 acetate (PMA), but was inhibited by the PKC inhibitor GF109203X. GF109203X-induced inhibition was not altered by removal of extracellular Ca(2+). In Ca(2+)-free medium, pretreatment with the endoplasmic reticulum Ca(2+) pump inhibitor thapsigargin (TG) or 2,5-di-tert-butylhydroquinone (BHQ) abolished honokiol-induced [Ca(2+)]i rise. Conversely, incubation with honokiol abolished TG or BHQ-induced [Ca(2+)]i rise. Inhibition of phospholipase C (PLC) with U73122 abolished honokiol-induced [Ca(2+)]i rise. Honokiol (20-80 μM) reduced the cell viability, which was not reversed by prechelating cytosolic Ca(2+) with BAPTA-AM (1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester). Honokiol (20-60 μM) enhanced reactive oxygen species (ROS) production, decreased mitochondrial membrane potential, released cytochrome c, and activated caspase-9/caspase-3. Together, honokiol induced a [Ca(2+)]i rise by inducing PLC-dependent Ca(2+) release from the endoplasmic reticulum and Ca(2+) entry via PKC-dependent, non store-operated Ca(2+) channels. Moreover, honokiol activated the mitochondrial pathway of apoptosis in DBTRG-05MG human glioblastoma cells.
    Chemico-Biological Interactions 08/2014; DOI:10.1016/j.cbi.2014.07.012 · 2.98 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Natural health products (NHPs) are defined as natural extracts containing polychemical mixtures; they play a leading role in the discovery and development of drugs, for disease treatment. More than 50% of current cancer therapeutics are derived from natural sources. However, the efficacy of natural extracts in treating cancer has not been explored extensively. Scientific research into the validity and mechanism of action of these products is needed to develop NHPs as main stream cancer therapy. The preclinical and clinical validation of NHPs would be essential for this development. This review summarizes some of the recent advancements in the area of NHPs with anticancer effects. This review also focuses on various NHPs that have been studied to scientifically validate their claims as anticancer agents. Furthermore, this review emphasizes the efficacy of these NHPs in targeting the multiple vulnerabilities of cancer cells for a more selective efficacious treatment. The studies reviewed here have paved the way for the introduction of more NHPs from traditional medicine to the forefront of modern medicine, in order to provide alternative, safer, and cheaper complementary treatments for cancer therapy and possibly improve the quality of life of cancer patients.
    Evidence-based Complementary and Alternative Medicine 01/2015; 2015:751348. DOI:10.1155/2015/751348 · 2.18 Impact Factor


Available from