- Research article
- Open Access
- Open Peer Review
Antiproliferative effect of Tualang honey on oral squamous cell carcinoma and osteosarcoma cell lines
© Ghashm et al; licensee BioMed Central Ltd. 2010
- Received: 15 May 2010
- Accepted: 14 September 2010
- Published: 14 September 2010
The treatment of oral squamous cell carcinomas (OSCC) and human osteosarcoma (HOS) includes surgery and/or radiotherapy which often lead to reduced quality of life. This study was aimed to study the antiproliferative activity of local honey (Tualang) on OSCC and HOS cell lines.
Several concentrations of Tualang honey (1% - 20%) were applied on OSCC and HOS cell lines for 3, 6, 12, 24, 48 and 72 hours. Morphological characteristics were observed under light and fluorescent microscope. Cell viability was assessed using MTT assay and the optical density for absorbance values in each experiment was measured at 570 nm by an ELISA reader. Detection of cellular apoptosis was done using the Annexin V-FITC Apoptosis Detection Kit.
Morphological appearance showed apoptotic cellular changes like becoming rounded, reduction in cell number, blebbed membrane and apoptotic nuclear changes like nuclear shrinkage, chromatin condensation and fragmented nucleus on OSCC and HOS cell lines. Cell viability assay showed a time and dose-dependent inhibitory effect of honey on both cell lines. The 50% inhibitory concentration (IC 50 ) for OSCC and HOS cell lines was found to be 4% and 3.5% respectively. The maximum inhibition of cell growth of ≥80% was obtained at 15% for both cell lines. Early apoptosis was evident by flow cytometry where percentage of early apoptotic cells increased in dose and time dependent manner.
Tualang honey showed antiproliferative effect on OSCC and HOS cell lines by inducing early apoptosis.
- Oral Cancer
- Oral Squamous Cell Carcinoma
- Oral Squamous Cell Carcinoma
- Early Apoptotic Cell
Cancer of the oral cavity is eleventh most common malignancy worldwide  while in the Indian subcontinent and regions of Southeast Asia, it is the predominant malignancy accounting for up to 40% of all the cancers . This high incidence of oral cancer is primarily attributable to the habit of tobacco, betel quid chewing and alcohol consumption .
Oral squamous cell carcinomas (OSCC) are the most common type of oral cancers. Similarly, Human Osteosarcomas (HOS) that arise from the jaw, account for 2.1% of all malignant oral and maxillofacial tumours . The treatment of these types of oral cancers includes surgery and/or radiotherapy, which are often associated with loss of function, disfigurement and reduced quality of life . Recently, advances in chemotherapeutic agents for the treatment of OSCCs have been highlighted but the survival rate of patients has not improved significantly. The development of novel therapeutic agents targeting the malignant behaviour of these cancers is important to improve the prognosis of treatment . The study of molecular mechanisms of chemotherapeutic agents and the combination of chemotherapeutic agents that induce synergistic anticancer activity are necessary to improve clinical outcomes .
Many researchers have studied the anticancer activities of drugs or herbal extracts on OSCC cell lines. These include Tamoxifen in combination with Cisplatin , 5-Fluorouracil , Cordycepin , Scutellaria baicalensis , Quercetin  Artemisinin  and others. Similarily, Ginsenoside Rg1, Cinnamic acid, and Tanshinone IIA , Diosgenin, Venenum Bufonis and Oxgall powder have been shown to have antiproliferative effect on HOS cell lines.
Honey is a food product which is collected from various plants and processed by honey bees (Apis mellifera). Honey has been used as traditional medicine for centuries in different cultures, not only for its nutritional value but also its healing properties. Recently, honey has been tested and approved scientifically for its functional and biological properties like anti-oxidant, anti-inflammatory, anti-bacterial, anti-viral, anti-ulcerous activities, anti-lipid and anti-cancer properties [16–23]. These activities are mainly attributed to the phenolic compounds such as flavonoids having antioxidant properties and radical scavenging activities seen among all types of honeys in different proportions, depending on the geographical areas, source of honeybee food and climate [24–26].
Honey has also been used in palliative care of various cancers like in radiation-induced mucositis, radiotherapy and chemotherapy induced skin reactions and wounds . It has also been shown to produce antiproliferative effects in bladder cancer , colon cancer , mammary carcinoma and fibrosarcoma . However, till date no study has been found to show antiproliferative effects of honey on oral cancers.
Malaysian Tualang honey is collected from the honey combs of Asian rock bees (Apis dorsata), which build their hives high up in the Tualang tree (Koompassia excelsa). Tualang honey is used commonly as a medicinal product  and as a food in Malaysia. Recently, antibacterial properties of this honey have been studied and compared with other honeys [30, 31]. However, its antiproliferative properties are yet to be studied. The purpose of the current study was to investigate the antiproliferative activity of Malaysian Tualang honey on OSCC and HOS cell lines.
Local Malaysian honey (Tualang honey), which was donated by the Food and Agricultural Ministry (FAMA), was used in this study. Working concentrations of honey were prepared fresh for each experiment by serial dilution with culture medium after which each concentration was filtered using 0.20 μm sterile filter unit (Sartorius stedim).
Cell culture materials
OSCC cell lines were purchased from American Tissue Collection Centre (ATCC) (CRL-1623) and were maintained in Dulbecco's Modified Eagle's Medium (DMEM) and Ham's F12 (DMEM/F12) (Sigma-Aldrich, USA). HOS cell lines were purchased from ATCC (CRL-1543) and were maintained in DMEM high glucose 1× (Gibco® invitrogen USA). Culture media was supplemented with 10% Foetal Bovine Serum (FBS) and 1% penicillin/streptomycin (Gibco® invitrogen).
Morphological analysis under light and fluorescent microscopy
For morphological analysis, OSCC and HOS cell lines were seeded in 60-mm dishes at 5 × 105 cells/ml. The cells were treated with 2% and 10% concentration of Tualang honey for 24, 48 and 72 hours. At the indicated time points, morphological changes were examined and recorded under light microscope (Carl Zeiss, Germany). Apoptosis was also determined morphologically at similar intervals and concentrations after staining the cells with Hoechst 33258 (Sigma-Aldrich) at a concentration of 20 μg/ml in PBS and incubated for 30 minutes. The cells were observed in the dark using Axioplan 2 fluorescent microscope (Carl Zeiss, Germany) at 356 nm.
MTT cell viability assay
OSCC and HOS cell lines were seeded in 96-well plate (Nunc™, Denmark) containing 1 × 104 cells with 100 μl serum medium. After the cells reached 70-80% confluence, they were treated with serum free medium containing Tualang honey concentrations from 1% to 20% for 3, 6, 12, 24 and 48 hours for all concentrations. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide or MTT (Calbiochem, Germany) was added at different time points with the final concentration of 0.5 mg/ml and then incubated for 4 hours at 37°C. The medium was removed and Dimethyl Sulphoxide (DMSO) (Ajax Finechem Pty Ltd, Australia) was added to dissolve the crystals by shaking the plate weakly for 15 minutes in the dark . The optical density (O.D.) of each treatment was measured at 570 nm by an ELISA reader (Sunrise, Tecan). Each experiment was performed in triplicates. Considering control untreated cells (cells without Tualang honey) as having 100% proliferation rate, the proliferation of cancer cells was expressed as the % cytoviability using the following formula: % cytoviability = A570 of treated cells/A570 of control cells × 100% .
Non-peroxidase, acidity and osmolar activity
Non-peroxidase activity of Tualang honey was measured by diluting it to 25% (w/v) by taking 1 ml of honey and adding it to either 1 ml of sterile purified water (total activity) or 1 ml of catalase solution. The 8000 U catalase solution (Sigma, C9322: 2950 units/mg) was used to remove all the hydrogen peroxide present in the honey. The removal of hydrogen peroxide was verified according to the method described elsewhere . Acidity of honey concentrations and culture medium was measured by pH 211 meter (Hanna instruments, USA). Osmolar control solution was prepared by mixing sugars namely 4 g fructose, 3 g glucose, 0.2 g sucrose and 0.8 g maltose mixed for 1 hour at 80°C to make in total 10 ml of the solution with distilled water. The solution was adjusted to be of the same osmolarity as that of honey concentrations by using an osmometer (Gonatec, Germany).
Cell apoptosis assay by flow cytometry
Cellular apoptosis was determined using the Annexin V-FITC Apoptosis Detection Kit I (Clontech Laboratories Inc, USA) according to the manufacturer's protocol. OSCC and HOS cell lines were cultured at 6 × 105 cells/ml and seeded in 60 mm dish. The cells were treated with free medium containing various concentrations of Tualang honey for 6, 12 and 24 hour. Cells were harvested by trypsinization, then washed twice with cold PBS and centrifuged at 1000 rpm. About 1 × 105 - 1 × 106 cells were then resuspended in 400 μl 1× binding buffer, centrifuged again at 1000 rpm for 5 minutes and then supernatant was removed. Cells were re-suspended in 200 μl 1× binding buffer and transferred to a sterile flow cytometry glass tube. Five μl Annexin V-FITC and 10 μl propidium iodide were added and then incubated in the dark at room temperature. Cells were analyzed by flow cytometer (FACSCalibur, Becton-Dickinson, USA) at 488 nm. The distribution of cells was analyzed using CellQuest™ software (Becton-Dickinson) in the flow cytometer within 1 hour of staining. Data from 10,000 cells was collected for each data file. Apoptotic cells were identified as Annexin V-FITC-positive and P-negative cells.
The data from MTT assay was analyzed by SPSS software version 12.0.1 and the results were expressed as median (IQR) of three independent experiments. As the data was not normally distributed and the assumption for equal variances was not fulfilled, Kruskal-Wallis test was applied. The pairwise comparison was analyzed using Mann-Whitney test and Bonferroni correction was applied. The difference in the median between the different concentrations and time points was considered to be statistically significant if the p- value was < 0.05.
Morphological changes in OSCC and HOS cell lines under light microscopy
Morphological changes in OSCC and HOS cell lines under fluorescence microscopy
Effect of Tualang honey on cell viability
Non-peroxidase, acidity and osmolar activity
Cell apoptosis assay results
Honey, a part of traditional medicine, has recently become the focus of attention for treating certain diseases as well as promoting overall health and well being. Several honey types from different floral sources and geographical regions have been reported to contain many phenolic compounds, which act as antioxidants and exhibit anti-carcinogenic, anti-inflammatory, anti-microbial, anti-atherogenic, anti-thrombotic, immune modulating and analgesic activities [36, 37]. In the oral health setting, honey has been found to be effective for the treatment of radiation-induced oral mucositis , stomatitis , reducing plaque and periodontal gum disease  and is also found to be anticariogenic .
In this study, we investigated the antiproliferative and apoptotic activities of Malaysian Tualang honey on human OSCC and HOS cell lines. This honey was chosen for the study as antiproliferative effects of this type of honey have not yet been verified on any type of the cancer cell lines. Additionally, in pure unprocessed honey like Tualang honey, there are a number of volatile compounds reported that may be missed in processing and fractionation . This is the first study to report the antiproliferative activity of honey on OSCC and HOS cell lines.
While most of the previous studies on honey have focused on its anti-microbial and wound healing properties, only few papers have looked into the anticarcinogenic properties of honey. Gribel and Pashinskii (1990) reported that honey revealed moderate antitumor and pronounced antimetastatic effects. Honey was also seen to potentiate the antitumor activity of 5-fluorouracil and cyclophosphamide . Wang et al. studied the anti-mutagenic effects of different types of honey against a commonly encountered dietary mutagen Trp-p-1 and found that all honeys exhibited significant inhibition of mutagenicity against this compound . In another study, bee honey was found to be an effective agent for inhibiting the growth of bladder cancer cell lines in vitro, and bladder cancer implanted mice models in vivo. A study done on tumour development and metastasis in murine tumour models using various honey-bee products showed an important role in controlling tumour growth and metastasis in mammary carcinoma and a methylcholanthrene-induced fibrosarcoma in mouse .
The present study showed that unfractionated Tualang honey has potential time and dose dependent antiproliferative effect on OSCC and HOS cancer cell lines. We found that IC50 for Tualang honey was 4% for OSCC and 3.5% for HOS cell lines. Non-peroxidase activity of honey was found to show the same effect as shown by various honey concentrations. Further, results of confirmatory experiments ruled out the low pH effect of honey as the reason for its antiproliferative activity. Similarly, the inhibitory effect of honey was found to be more than the effect of analogous osmolar solutions. Thus, hydrogen peroxide activity, acidity and hyperosmolarity of honey were ruled out for its inhibitory effect on these cancer cell lines. A recent article suggested that the polyphenols found in honey, like Caffeic acid, Caffeic acid phenyl esters, Chrysin, Galangin, Quercetin, Kaempferol, Acacetin, Pinocembrin, Pinobanksin and Apigenin, to be promising pharmacological agents in the treatment of cancer by reviewing their antiproliferative and molecular mechanisms . These compounds have been shown to exhibit an inhibitory effect on tumour cell proliferation and transformation by the down regulation of many cellular enzymatic pathways including protein tyrosine kinase, cycloxygenase and ornithine decarboxylase pathways . Another study done on jungle honey obtained from the tropical forest of Nigeria showed that this type of honey possessed chemotactic activity for neutrophils, which were found to possess potent antitumour activity mediated by reactive oxygen species (ROS) .
As shown by our flow cytometry results, when the concentration of honey was increased, the percentage of early apoptotic cells also increased. For this reason, the mode of cell death appears to be due to early apoptosis cell death pathway. These apopototic changes were also visible in the morphological studies which were done using light and fluorescent microscopy where membrane blebs, chromatin and nuclear condensation, DNA fragmentation and formation of apoptotic bodies were seen. A change in the status of the intracellular non-protein thiol, fall in MMP and increased ROS generation were reported to occur during apoptosis . Moreover, the expression of various proapoptotic and antiapoptotic proteins was found to be altered during apoptosis . A recent study done to understand the molecular mechanism of honey in colon cancer cell growth inhibition found that honey induced apoptosis was accompanied by up-regulating the p53 and modulating the expression of pro and anti-apoptotic proteins . They also reported that unfractionated honey induced cell-growth arrest, resulting in cell cycle blockage at the sub-G1 phase. Further, it transduced the apoptotic signal via initial depletion of intracellular non-protein thiols (GSH), consequently reducing the MMP and increasing the ROS generation. Similar studies need to be done in OSCC and HOS cell lines to confirm these findings.
In conclusion, the results of this study suggest that Tualang honey has a promising antiproliferative and apoptotic effect on OSCC and HOS cell lines. Early apoptosis could be attributed, in part, to its ability to inhibit proliferation. Further investigations are needed to determine the molecular mechanisms involved in apoptosis.
This study was supported by short-term grant No. 304/PPSG/6131628 provided by Universiti Sains Malaysia.
- WHO: Global data on incidence of oral cancer. Oral health programme. 2005, GenevaGoogle Scholar
- Moore SR, Johnson NW, Pierce AM, Wilson DF: The epidemiology of mouth cancer: a review of global incidence. Oral Dis. 2000, 6 (2): 65-74. 10.1111/j.1601-0825.2000.tb00104.x.View ArticlePubMedGoogle Scholar
- La Vecchia C, Tavani A, Franceschi S, Levi F, Corrao G, Negri E: Epidemiology and prevention of oral cancer. Oral Oncol. 1997, 33 (5): 302-312. 10.1016/S1368-8375(97)00029-8.View ArticlePubMedGoogle Scholar
- Chen WL, Feng HJ, Li HG: Expression and significance of hypoxemia-inducible factor-1alpha in osteosarcoma of the jaws. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2008, 106 (2): 254-257. 10.1016/j.tripleo.2008.01.029.View ArticlePubMedGoogle Scholar
- Day TA, Davis BK, Gillespie MB, Joe JK, Kibbey M, Martin-Harris B, Neville B, Richardson MS, Rosenzweig S, Sharma AK: Oral cancer treatment. Curr Treat Options Oncol. 2003, 4 (1): 27-41. 10.1007/s11864-003-0029-4.View ArticlePubMedGoogle Scholar
- Bramer JA, van Linge JH, Grimer RJ, Scholten RJ: Prognostic factors in localized extremity osteosarcoma: a systematic review. Eur J Surg Oncol. 2009, 35 (10): 1030-1036.View ArticlePubMedGoogle Scholar
- Kim MJ, Lee JH, Kim YK, Myoung H, Yun PY: The role of tamoxifen in combination with cisplatin on oral squamous cell carcinoma cell lines. Cancer Lett. 2007, 245 (1-2): 284-292. 10.1016/j.canlet.2006.01.017.View ArticlePubMedGoogle Scholar
- Tong D, Poot M, Hu D, Oda D: 5-Fluorouracil-induced apoptosis in cultured oral cancer cells. Oral Oncol. 2000, 36 (2): 236-241. 10.1016/S1368-8375(99)00079-2.View ArticlePubMedGoogle Scholar
- Wu WC, Hsiao JR, Lian YY, Lin CY, Huang BM: The apoptotic effect of cordycepin on human OEC-M1 oral cancer cell line. Cancer Chemother Pharmacol. 2007, 60 (1): 103-111. 10.1007/s00280-006-0354-y.View ArticlePubMedGoogle Scholar
- Zhang DY, Wu J, Ye F, Xue L, Jiang S, Yi J, Zhang W, Wei H, Sung M, Wang W: Inhibition of cancer cell proliferation and prostaglandin E2 synthesis by Scutellaria baicalensis. Cancer Res. 2003, 63 (14): 4037-4043.PubMedGoogle Scholar
- Haghiac M, Walle T: Quercetin induces necrosis and apoptosis in SCC-9 oral cancer cells. Nutr Cancer. 2005, 53 (2): 220-231. 10.1207/s15327914nc5302_11.View ArticlePubMedGoogle Scholar
- Nam W, Tak J, Ryu JK, Jung M, Yook JI, Kim HJ, Cha IH: Effects of artemisinin and its derivatives on growth inhibition and apoptosis of oral cancer cells. Head Neck. 2007, 29 (4): 335-340. 10.1002/hed.20524.View ArticlePubMedGoogle Scholar
- Shi SL, Li QF, Liu QR, Xu DH, Tang J, Liang Y, Zhao ZL, Yang LM: Nuclear matrix protein, prohibitin, was down-regulated and translocated from nucleus to cytoplasm during the differentiation of osteosarcoma MG-63 cells induced by ginsenoside Rg1, cinnamic acid, and tanshinone IIA (RCT). J Cell Biochem. 2009, 108 (4): 926-934. 10.1002/jcb.22324.View ArticlePubMedGoogle Scholar
- Corbiere C, Liagre B, Bianchi A, Bordji K, Dauca M, Netter P, Beneytout JL: Different contribution of apoptosis to the antiproliferative effects of diosgenin and other plant steroids, hecogenin and tigogenin, on human 1547 osteosarcoma cells. Int J Oncol. 2003, 22 (4): 899-905.PubMedGoogle Scholar
- Wang J, Yin JQ, Shen JN, Jia Q, Huang G, Jin S, Zou CY: In vitro screening of 32 traditional Chinese herbal extracts against U2OS human osteosarcoma cells. Nan Fang Yi Ke Da Xue Xue Bao. 2006, 26 (9): 1293-1296.PubMedGoogle Scholar
- Irish J, Carter DA, Blair SE, Heard TA: Antibacterial activity of honey from the Australian stingless bee Trigona carbonaria. Int J Antimicrob Agents. 2008, 32 (1): 89-90. 10.1016/j.ijantimicag.2008.02.012.View ArticlePubMedGoogle Scholar
- Temaru E, Shimura S, Amano K, Karasawa T: Antibacterial activity of honey from stingless honeybees (Hymenoptera; Apidae; Meliponinae). Pol J Microbiol. 2007, 56 (4): 281-285.PubMedGoogle Scholar
- Gheldof N, Engeseth NJ: Antioxidant capacity of honeys from various floral sources based on the determination of oxygen radical absorbance capacity and inhibition of in vitro lipoprotein oxidation in human serum samples. J Agric Food Chem. 2002, 50 (10): 3050-3055. 10.1021/jf0114637.View ArticlePubMedGoogle Scholar
- Estevinho L, Pereira AP, Moreira L, Dias LG, Pereira E: Antioxidant and antimicrobial effects of phenolic compounds extracts of Northeast Portugal honey. Food Chem Toxicol. 2008, 46 (12): 3774-3779. 10.1016/j.fct.2008.09.062.View ArticlePubMedGoogle Scholar
- Wang XH, Andrae L, Engeseth NJ: Antimutagenic effect of various honeys and sugars against Trp-p-1. J Agric Food Chem. 2002, 50 (23): 6923-6928. 10.1021/jf025641n.View ArticlePubMedGoogle Scholar
- Swellam T, Miyanaga N, Onozawa M, Hattori K, Kawai K, Shimazui T, Akaza H: Antineoplastic activity of honey in an experimental bladder cancer implantation model: in vivo and in vitro studies. Int J Urol. 2003, 10 (4): 213-219. 10.1046/j.0919-8172.2003.00602.x.View ArticlePubMedGoogle Scholar
- Orsolic N, Terzic S, S L, Basic I: Honey-bee products in prevention and/or therapy of murine transplantable tumours. J Sci Food Agric. 2005, 85: 363-370. 10.1002/jsfa.2041.View ArticleGoogle Scholar
- Boukraa L, Amara K: Synergistic effect of starch on the antibacterial activity of honey. J Med Food. 2008, 11 (1): 195-198. 10.1089/jmf.2007.502.View ArticlePubMedGoogle Scholar
- Beretta G, Orioli M, Facino RM: Antioxidant and radical scavenging activity of honey in endothelial cell cultures (EA.hy926). Planta Med. 2007, 73 (11): 1182-1189. 10.1055/s-2007-981598.View ArticlePubMedGoogle Scholar
- Viuda-Martos M, Ruiz-Navajas Y, Fernandez-Lopez J, Perez-Alvarez JA: Functional properties of honey, propolis, and royal jelly. J Food Sci. 2008, 73 (9): R117-124. 10.1111/j.1750-3841.2008.00966.x.View ArticlePubMedGoogle Scholar
- Hegazi AG, Abd El-Hady FK: Influence of Honey on the Suppression of Human Low Density Lipoprotein (LDL) Peroxidation (In vitro). Evid Based Complement Alternat Med. 2009, 6 (1): 113-121. 10.1093/ecam/nem071.View ArticlePubMedGoogle Scholar
- Bardy J, Slevin NJ, Mais KL, Molassiotis A: A systematic review of honey uses and its potential value within oncology care. J Clin Nurs. 2008, 17 (19): 2604-2623. 10.1111/j.1365-2702.2008.02304.x.View ArticlePubMedGoogle Scholar
- Rao CV, Desai D, Rivenson A, Simi B, Amin S, Reddy BS: Chemoprevention of colon carcinogenesis by phenylethyl-3-methylcaffeate. Cancer Res. 1995, 55 (11): 2310-2315.PubMedGoogle Scholar
- Ghazali FC: Morphological characterization study of Malaysian honey - A VPSEM, EDX randomised attempt. Annals of Microscopy. 2009, 9: 93-102.Google Scholar
- Tan HT, Rahman RA, Gan SH, Halim AS, Hassan SA, Sulaiman SA, Kirnpal-Kaur B: The antibacterial properties of Malaysian tualang honey against wound and enteric microorganisms in comparison to manuka honey. BMC Complement Altern Med. 2009, 9: 34-10.1186/1472-6882-9-34.View ArticlePubMedPubMed CentralGoogle Scholar
- Tumin N, Halim NA, Shahjahan M, Noor Izani NJ, Sattar MA, Khan AH, Mohsin SSJ: Antibacterial activity of local Malaysian honey. Mal J of Pharmaceut Sci. 2005, 3 (2): 1-10.Google Scholar
- Wang X, Yuan S, Wang J, Lin P, Liu G, Lu Y, Zhang J, Wang W, Wei Y: Anticancer activity of litchi fruit pericarp extract against human breast cancer in vitro and in vivo. Toxicol Appl Pharmacol. 2006, 215 (2): 168-178. 10.1016/j.taap.2006.02.004.View ArticlePubMedGoogle Scholar
- Allen KL, Molan PC, Reid GM: A survey of the antibacterial activity of some New Zealand honeys. J Pharm Pharmacol. 1991, 43 (12): 817-822.View ArticlePubMedGoogle Scholar
- Hsiao JR, Leu SF, Huang BM: Apoptotic mechanism of paclitaxel-induced cell death in human head and neck tumor cell lines. J Oral Pathol Med. 2009, 38 (2): 188-197. 10.1111/j.1600-0714.2008.00732.x.View ArticlePubMedGoogle Scholar
- Pietra G, Mortarini R, Parmiani G, Anichini A: Phases of apoptosis of melanoma cells, but not of normal melanocytes, differently affect maturation of myeloid dendritic cells. Cancer Res. 2001, 61 (22): 8218-8226.PubMedGoogle Scholar
- Gomez-Caravaca AM, Gomez-Romero M, Arraez-Roman D, Segura-Carretero A, Fernandez-Gutierrez A: Advances in the analysis of phenolic compounds in products derived from bees. J Pharm Biomed Anal. 2006, 41 (4): 1220-1234. 10.1016/j.jpba.2006.03.002.View ArticlePubMedGoogle Scholar
- Simon A, Traynor K, Santos K, Blaser G, Bode U, Molan P: Medical honey for wound care--still the 'latest resort'?. Evid Based Complement Alternat Med. 2009, 6 (2): 165-173. 10.1093/ecam/nem175.View ArticlePubMedGoogle Scholar
- Biswal BM, Zakaria A, Ahmad NM: Topical application of honey in the management of radiation mucositis: a preliminary study. Support Care Cancer. 2003, 11 (4): 242-248.PubMedGoogle Scholar
- Chiba M, Idobata K, Kobayashi N, Sato Y, Muramatsu Y: Use of honey to ease the pain of stomatitis during radiotherapy. Kangogaku Zasshi. 1985, 49 (2): 171-176.PubMedGoogle Scholar
- English HK, Pack AR, Molan PC: The effects of manuka honey on plaque and gingivitis: a pilot study. J Int Acad Periodontol. 2004, 6 (2): 63-67.PubMedGoogle Scholar
- Sela M, Maroz D, Gedalia I: Streptococcus mutans in saliva of normal subjects and neck and head irradiated cancer subjects after consumption of honey. J Oral Rehabil. 2000, 27 (3): 269-270. 10.1046/j.1365-2842.2000.00504.x.View ArticlePubMedGoogle Scholar
- Gribel NV, Pashinskii VG: The antitumor properties of honey. Vopr Onkol. 1990, 36 (6): 704-709.PubMedGoogle Scholar
- Jaganathan SK, Mandal M: Antiproliferative effects of honey and of its polyphenols: a review. J Biomed Biotechnol. 2009, 2009: 1-13. 10.1155/2009/830616.View ArticleGoogle Scholar
- Rao CV, Desai D, Simi B, Kulkarni N, Amin S, Reddy BS: Inhibitory effect of caffeic acid esters on azoxymethane-induced biochemical changes and aberrant crypt foci formation in rat colon. Cancer Res. 1993, 53 (18): 4182-4188.PubMedGoogle Scholar
- Fukuda M, Kobayashi K, Hirono Y, Miyagawa M, Ishida T, Ejiogu EC, Sawai M, Pinkerton KE, Takeuchi M: Jungle Honey Enhances Immune Function and Antitumor Activity. Evid Based Complement Alternat Med. 2009, 1-8.Google Scholar
- Lee HC, Wei YH: Mitochondrial role in life and death of the cell. J Biomed Sci. 2000, 7 (1): 2-15. 10.1007/BF02255913.View ArticlePubMedGoogle Scholar
- Hengartner MO: The biochemistry of apoptosis. Nature. 2000, 407 (6805): 770-776. 10.1038/35037710.View ArticlePubMedGoogle Scholar
- Jaganathan SK, Mandal M: Involvement of non-protein thiols, mitochondrial dysfunction, reactive oxygen species and p53 in honey-induced apoptosis. Invest New Drugs. 2010, 28 (5): 624-33. 10.1007/s10637-009-9302-0.View ArticlePubMedGoogle Scholar
- The pre-publication history for this paper can be accessed here:http://www.biomedcentral.com/1472-6882/10/49/prepub
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.