• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.4
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• pp.587-593
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• 1998

To elucidate anti-tumor promoter from seaweed, the anti-tumor promoting activity of Ecklonia stolonifera, Undaria pinnatifida and Laminaria japonica extracts were determined by Epstein-Barr virus (EBV)-early antigen (EA) induction caused by a tumor promoter, teleocidin B-4. The methanol extracts of seaweed were subsequently fractionated with diethyl ether, distilled water, chloroform and ethyl acetate. Among the solvent fractions tested, chloroform and ethyl acetate fraction of E. stolonifera showed a high anti-tumor promoting activity at the levels of 88.0 and $85.9\%$ by the addition of 20 ${\mu}g/m{\ell}$, respectively. To characterize anti-tumor promoters from solvent fractions of E. stolonifera, the effects of phenols, chlorophyll derivatives and carotenoids on the anti-tumor promoting activity were investigated. Phenols, such as bromophenol and phloroglucinol showed anti-tumor promoting activity of $57\~66\%$ at 20 ${\mu}g/m{\ell}$. Pigments, such as chlorophylls and carotenoids exerted high anti-tumor promoting activities. Chlorophyll a and pheophorbide a exhibited the activity of $77.4\%$ and $66.6\%$ at 5${\mu}M/m{\ell}$, respectively. The active compounds of carotenoids were tentatively identified as lutein and $\alpha-cryptoxanthin$ from the profiles of visible spectra and R_f value of their authentic compounds, and showed anti-tumor promoting activities of $76.9\%$ and $84.4\%$ at dose of 20 ${\mu}g/m{\ell}$, respectively.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.4
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• pp.2301-2305
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• 2013

Ardisia crispa (Family: Myrsinaceae) is an evergreen, fruiting shrub that has been traditionally used as folklore medicine. Despite a scarcity of research publications, we have succeeded in showing suppressive effects on murine skin papillomagenesis. In extension, the present research was aimed at determining the effect of a quinone-rich fraction (QRF) isolated from the same root hexane extract on both initiation and promotion stages of carcinogenesis, at the selected dose of 30 mg/kg. Mice (groups I-IV) were initiated with a single dose of 7,12-dimethylbenz(${\alpha}$)anthracene (DMBA, $100{\mu}g/100{\mu}l$) followed by repeated promotion of croton oil (1%) twice weekly for 20 weeks. In addition, group I (anti-initiation) received QRF 7 days before and after DMBA; group II (anti-promotion) received QRF 30 minutes before each croton oil application; group III (anti-initiation/promotion) was treated with QRF as a combination of group I and II. A further two groups served as vehicle control (group V) and treated control (group VI). As carcinogen control, group IV showed the highest tumor volume ($8.79{\pm}5.44$) and tumor burden ($3.60{\pm}1.17$). Comparatively, group III revealed only 20% of tumor incidence, tumor burden ($3.00{\pm}1.00$) and tumor volume ($2.40{\pm}1.12$), which were significantly different from group IV. Group II also showed significant reduction of tumor volume (3.11), tumor burden (3.00) and tumor incidence (11.11%), along with prominent increase of latency period of tumor formation (week 12). Group I, nonetheless, demonstrated marked increment of tumor incidence by 40% with prompted latency period of tumor formation (week 7). No tumor formation was observed in groups V and VI. This study provided clear evidence of inhibitory effects of QRF during promotion period which was in agreement with our previous findings. The mechanism(s) underlying such effects have yet to be elucidated.

• Journal of Photoscience
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• v.9 no.2
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• pp.221-224
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• 2002

Carcinogenesis can be theoretically divided to intiation step and promotion step. Intiation associates with genetic alterations including p53 tumor suppressor gene and ras oncogene. Promotion involves in clonal expansion of of an initiated cell by epigenetic mechanism, mainly through signal transduction and gene expression. Ultraviolet light (UV) acts as both initiator and promoter. Initiation is closely related with DNA damage induced by UV, including cyclobutane pyrimidine dimers, (6-4) photoproducts and 8-hydroxy-2'-deoxyguanosine. Cyclobutane pyrimidine dimers and (6-4) photoproducts are directly induced by UV, while 8-hydroxy-2'-deoxyguanosine is induced indirectly by the reactive oxygen species. Because initiation is an irreversal genetic event, while promotion is a reversal and epigenetic event, to know the molecular mechanisms of tumor promotion in UV-carcinogenesis is crucial to develop preventive medicine and suppress UV-carcinogenesis. Because ROS is also involved in signal transduction of the cell, anti-oxidant could be the good candidate of anti-promoting agent. Here, we describe the suppressive effect of UV-carcinogenesis by various anti-oxidant including olive oil. In addition, we discuss about the mechanism of UVB-induced expression of cyclooxygenase-2, which might be a representative molecule involved in promotion of UV-carcinogenesis.

• THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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• v.9 no.1
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• pp.53-63
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• 2003

This study was analyzed the effects of blood-activating and stasis-eliminating herbs on anti-tumor and hematogenic metastasis. The metastasis and recurrence of tumor was the basis of yudok(yudu) on remained tumor cell and stagnation of blood, thermotoxo, phlegm, asthenia of healthy enerngy, stagnation of vital energy. Malignant tumor is caused by carcinogen and go through the progress of initiation, promotion, progression, it is closely related with Eohyul$(y{\grave{u}}xi {\breve{e}})$. Symptoms of blood stasis disease are purplish tongue, mass, fixed stabbing pain, ecchymosis of nail, hypodermic petechia, dermal thesaurismosis, melena, ecchymoma, disturbance of circulation. Effects on the therapy of activating blood circulation and congestion are anti-tumor, anti-coagulation, anti-hemolysis, anti-solution, anti-inflammation, anti-infection, control of blood circulations, control of connective tissue metabolism and control of immunity. They can directly kill the cancer cells entering the blood circulation, inhibit the formation of tumor embody and reduce the blood hyperviscosity. It is suggested that these herbs can be used to prevent and treat blood metastasis of cancer under the guidance of syndrome differentiation.

• BMB Reports
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• v.36 no.1
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• pp.66-77
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• 2003

Tea is one of the most popular beverages consumed in the world and has been demonstrated to have anti-cancer activity in animal models. Research findings suggest that the polyphenolic compounds, (-)-epigallocatechin-3-gallate, found primarily in green tea, and theaflavin-3,3'-digallate, a major component of black tea, are the two most effective anti-cancer factors found in tea. Several mechanisms to explain the chemopreventive effects of tea have been presented but others and we suggest that tea components target specific cell-signaling pathways responsible for regulating cellular proliferation or apoptosis. These pathways include signal transduction pathways leading to activator protein-1 (AP-1) and/or nuclear factor kappa B(NF-${\kappa}B$ ). AP-1 and NF-${\kappa}B$ are transcription factors that are known to be extremely important in tumor promoter-induced cell transformation and tumor promotion, and both are influenced differentially by the MAP kinase pathways. The purpose of this brief review is to present recent research data from other and our laboratory focusing on the tea-induced cellular signal transduction events associated with the MAP kinase, AP-1, and NF-${\kappa}B$ pathways.

• Applied Biological Chemistry
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• v.49 no.1
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• pp.25-29
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• 2006

This study was carried out to isolate the possible anti-tumor promoters from the citrus peel (Citrus natsudaidai Hayata). We fractionated the cold-pressed oil of citrus peel by column chromatography, HPLC and TLC. The analysis on column chromate-graphy yielded seven peaks $(F-I{\sim}F-VII)$, all of which showed single spot on TLC analysis ($R_f$ for $F-I{\sim}VIII$; 0.31, 0.13, 0.13, 0.78, 0.79, 0.69 and 0.84). Among the seven fractions, three fractions (F-I, -II and F-IV) were re-analyzed on HPLC, also showing single peak except for one fraction (F-IV) which was divided two peaks. The retention times $(R_f)$ of F-I and F-II was 3 min. and 2.5 min., respectively, but these of two peaks from F-IV were 2 min. and 4.5 min., respectively. Since the area of the latter peak (4.5 min.) was very smaller than that of the former one (2 min.), it is considered that the latter one did not appear on TLC analysis. The inhibitory effect on tumor promoter 12-O-tetradecanoylphorbol-13-acetate(TPA)-induced Epstein-Barr virus activation in Raji cells was tested for the seven fraction obtained. It decreased in order of F-VI (82.3+1.3%) > F-I (80.4+1.6%) > F-II (77.2+0.9%) > F-III (75.0+1.2%) > F-IV (74.1=1.0%) > F-V (71.0+1.1%) > F-VII (70.2+1.2%). These results imply that some constiuents contained in citrus peels have the inhibitory activity of TPA-induced tumor promotion.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2533-2539
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• 2012

Annona muricata L (Annonaceae), commonly known as soursop has a long, rich history in herbal medicine with a lengthy recorded indigenous use. It had also been found to be a promising new anti-tumor agent in numerous in vitro studies. The present investigation concerns chemopreventive effects in a two-stage model of skin papillomagenesis. Chemopreventive effects of an ethanolic extract of A. muricata leaves (AMLE) was evaluated in 6-7 week old ICR mice given a single topical application of 7,12-dimethylbenza(${\alpha}$)anthracene (DMBA 100ug/100ul acetone) and promotion by repeated application of croton oil (1% in acetone/twice a week) for 10 weeks. Morphological tumor incidence, burden and volume were measured, with histological evaluation of skin tissue. Topical application of AMLE at 30, 100 and 300mg/kg significantly reduced DMBA/croton oil induced mice skin papillomagenesis in (i) peri-initiation protocol (AMLE from 7 days prior to 7 days after DMBA), (ii) promotion protocol (AMLE 30 minutes after croton oil), or (iii) both peri-initiation and promotion protocol (AMLE 7 days prior to 7 day after DMBA and AMLE 30 minutes after croton oil throughout the experimental period), in a dose dependent manner (p<0.05) as compared to carcinogen-treated control. Furthermore, the average latent period was significantly increased in theAMLE-treated group. Interestingly, At 100 and 300 mg/kg, AMLE completely inhibited the tumor development in all stages. Histopathological study revealed that tumor growth from the AMLE-treated groups showed only slight hyperplasia and absence of keratin pearls and rete ridges. The results, thus suggest that the A.muricata leaves extract was able to suppress tumor initiation as well as tumor promotion even at lower dosage.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.149.3-150
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• 2003

[6]-Gingerol, a major pungent ingredient of ginger (Zingiber officinale Roscoe, Zingiberaceae) has a wide array of pharmacologic effects. Our previous studies have demonstrated that [6]-gingerol inhibits mouse skin tumor promotion and anchorage-independent growth of cultured mouse epidermal cells stimulated with epidermal growth factor. In this study, we have investigated the molecular mechanisms underlying anti-tumor promoting effects of ［6］-gingerol on mouse skin carcinogenesis. (omitted)

• Natural Product Sciences
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• v.5 no.1
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• pp.33-38
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• 1999

Ethanolic extracts of different parts of 10 local traditional vegetables (ulam) (Amaranthus gangeticus, Jussiaea linifolia, Eugenia polyantha, Trapa incisa, Trichosanthes anquina, Mangifera indica, Pachyrrhirus erosus, Barringtonia mcarostachya, Carica papaya, and Coleus tuberosus) were screened for in vitro antitumor promoting activity using the inhibition test of Epstein-Barr virus (EBV) activation in Raji cells induced by phorbol 12-myristate 13-acetate and sodium-n-butyrate. All the extracts were found to have strong inhibition activity toward EBV-activation, except for leaf extract of T. anquina. The extracts were non-cytotoxic to the Raji cells except for the extracts of A. gangeticus (leaves), B. macrostachya (leaves), E. polyantha (young leaves), and J. linifolia (leaves) where the viability of the cells were decreased significantly.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.9
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• pp.4393-4402
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• 2012

Colon cancer is the third most common malignant neoplasm in the world and it remains an important cause of death, especially in western countries. The toxic environmental pollutant, 1, 2-dimethylhydrazine (DMH), is also a colon-specific carcinogen. Tannic acid (TA) is reported to be effective against various types of chemically induced toxicity and also carcinogenesis. In the present study, we evaluated the chemopreventive efficacy of TA against DMH induced colon toxicity in a rat model. Efficacy of TA against the colon toxicity was evaluated in terms of biochemical estimation of antioxidant enzyme activities, lipid peroxidation, histopathological changes and expression of early molecular markers of inflammation and tumor promotion. DMH treatment induced oxidative stress enzymes (p<0.001) and an early inflammatory and tumor promotion response in the colons of Wistar rats. TA treatment prevented deteriorative effects induced by DMH through a protective mechanism that involved reduction of oxidative stress as well as COX-2, i-NOS, PCNA protein expression levels and TNF-${\alpha}$ (p<0.001) release. It could be concluded from our results that TA markedly protects against chemically induced colon toxicity and acts plausibly by virtue of its antioxidant, anti-inflammatory and antiproliferative activities.