• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.141-146
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• 2004

Fungal products indirectly mediate anti-tumor effects in vitro and in vivo. To investigate whether Lentinus edodes might possess direct anti-tumor substance, L. edodes was extracted and tested on human papillomavirus (HPV) 16 oncogenes-associated animal tumor cells (TC-1) and in an animal tumor model. Only water extract displayed direct anti-proliferative effects in TC-1 tumor cells in vitro. This inhibition was dose-dependent, and inhibitory concentration ($IC_{50}$) was $800\;{\mu}g/mL$. Fungal extracts also showed growth inhibition to human cervical cancer cells (CaSki and HeLa) similarly to TC-1 tumor cells. When fungal extracts were added at a high dose (1.5 mg/mL), cell growth was inhibited within 6 hr following extract treatment. Cell growth inhibition was blocked by heat treatment, but not by low pH, which is indicative of heat sensitivity of this anti-proliferative substance. Cell growth suppression was mediated by apoptosis, as determined by Annexin V and propidium iodide staining. When challenged with TC-1 cells, direct intratumoral injection of fungal extracts resulted in some positive effect on tumor growth inhibition, as compared to oral delivery. Results suggest that heat labile substance of L. edodes suppresses growth of HPV oncogenes-associated tumor cells through apoptosis.

• Korean Journal of Pharmacognosy
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• v.35 no.4 s.139
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• pp.368-374
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• 2004

Cervical cancer is one of the leading causes of female death. Viral oncoproteins E6 and E7 are selectively retained and expressed in carcinoma cells infected with HPV (Human papillomavirus) type 16. The HPV is cooperated in immotalization and transformation of primary keratinocyte. E6 and E7 oncoproteins interfere the functions of tumor suppressor proteins p53 and retinoblasoma protein (pRb), respectively. Among a lots of natural products, Artemisia scoparia Waldstein et Kitamura has inhibitory effects on the binding between E6 oncoprotein and tumor suppressor p53, or the binding between E6 and E6 associated protein (E6AP), an E3 ubiquitin-protein ligase. HPV oncoprotein inhibitors from Artemisia scoparia W. were isolated by solvent partition and column chromatography (Silica gel, RP-18) and the inhibitory compounds were finally purified by HPLC using an ELISA screening system based on the binding between E6 and E6AP. The aim of this study is to identify the structure of inhibitory compounds and to investigate whether these compounds have inhibitory effects on the functions of E6 oncoprotein. We investigated whether 3,5-di-O-caffeoylquinic acid (DCQA) extracted from Artemisia scoparia W. Could inhibit the function of E6 oncoprutein. DCQA inhibited the in vitro binding of E6 and E6AP which are essential for the binding and degradation of the tumor suppressor p53 and also inhibited the proliferation of human cervical cancer cell lines (SiHa and CaSKi) in a dose response manner. These results suggest that DCQA inhibited the function of E6 oncoprotein, suggesting that it can be used as a potential drug for the treatment of cervical cancers infected with HPV.