Metastasis is the primary cause of from breast cancer mortality. Cell migration and invasion play important roles in neoplastic metastasis. Matrix metalloproteinase-9 (MMP-9), which degrades the extracellular matrix (ECM), plays an important role in cancer cell invasion. NF-κB is transcription factor important in the regulation of MMP-9, as the promoter of MMP-9 gene contains binding sites for NF-κB. Brazilin, an active component of sappan wood (Caesalpinia sappan), decreases TPA-induced MMP-9 expression and invasion in MCF-7 cells. Also, brazilin suppressed NF-κB activation in TPA-treated MCF-7 cells. Taken together, we demonstrated that the inhibition of TPA-induced MMP-9 expression and cell invasion by brazilin is mediated by the suppression of the NF-κB pathway in MCF-7 cells. This result suggest brazilin provide a potential therapeutic approach for the treatment of breast cancer.

약용식물내 에스트로겐성과 항-에스트로겐성을 조사하고 항암인자를 발견하기 위하여, 본연구는 에탄올추출로 제조된 9종류의 한국산 약용식물에 대하여 재조합효모와 MCF-7 사람유방암세포주를 이용하여 스크리닝하고 비교하였다. 재조합효모를 이용한 실험결과, 7종류의 약용식물에서 에스트로겐성이 나타났고, 4종류에서 안드로겐성이 나타났다. 또한 MCF-7 사람유방암세포주를 이용한 실험결과, 8종류의 추출물이 MCF-7 세포의 성장을 억제하는 것으로 확인되었으며 비스페놀 A와 동시 처치한 경우에도 유의적으로 억제하는 것으로 나타났다. 또한 Clyeyrrhiza uralensis, Cassia tora, Syringa velutina, Zingiber officinale, Malva verticillata, Panax ginseng C.A. Meyer는 식물성 에스트로겐으로서 에스트로겐에 양성인 사람유방암세포의 증식을 유의적으로 억제시티는 흥미로운 결과가 제시되었다. 따라서 이번 연구는 한국산 약용식물이 식물성 에스트로겐과 항암인자로서 이용될 수 있으며, 에스트로겐의 활성을 조사하는데 유용하게 이용될 수 있을 것으로 사료된다.

Dendropanax morbifera Léveille (Araliaceae) is an endemic species growing in the south-western part of South Korea and has been used in folk medicine and health functional food. Several studies have indicated that extract of D. morbifera (DP) has cytotoxic activities on a number of human cancers, such as, breast cancer, lung cancer, hepatoma, and chorioepithelioma. Recently, polyacetylene and triterpene compounds have been isolated from the DP and showed to have anti-complement activity. β-Amyrin, α-amyrin, dendropanoxide, and β-sitosterol are isolated from DP. However, its biological activities in cancer have not yet been clearly elucidated. In this study, we evaluated the anti-cancer activity of isolated triterpenoids from the DP leaves by measuring the levels of cytotoxicity against MCF-7 human breast cancer and A549 human lung cancer cells. Six triterpenoids were isolated from the n-hexane fraction of DP leaves along with the known compounds. β-amyrin (1), α-amyrin (2), olean-12-en-3,24 β-diol (3), dendropanoxide (4), β-sitosterol (5), and stigmasterol (6). Compound 3 and 6 were isolated from DP for the first time. Cytotoxic activities of six compounds were evaluated against two human cancer cell lines by using the MTT in vitro assay. Among them, five compounds (1, 2, 4, 5, and 6) showed moderate cytotoxic activities toward the tested cell lines, and were safe to normal cells. Western blot analysis showed a decreased expression of anti-apoptotic protein Bcl-2 and increased levels of pro-apoptotic protein Bax in MCF-7 and A549 cells treated by β-amyrin and α-amyrin. Flow cytometry analysis confirmed that five compounds (1, 2, 4, 5, and 6) treatment increased populations of sub-G1 (apoptosis) phase. The results of the present study revealed that triterpenoids from DP have the potential for further development as anticancer agents.

Chemoresistance is one of the main problems to treat different kinds of cancers or cancer cells. Therefore, it is necessary to find out the strategies to make the cancer cells sensitive to chemotherapy along with optimal dosage of drugs. We examined sensitivity of MCF7 cells through pretreating with an epigenetic modulator, azacytidine (AzaC) to doxorubicin (Dox). The cells were treated with 5 and 10 mM of AzaC for a week, subsequently with 50, 100 and 500 nM of doxorubicin for 24 and 48h. It was found that pretreatment of AzaC significantly enhance the sensitivity of MCF7 cells to Dox, inducing cell death. After 24h 15% cells underwent apoptosis in 500 nM dox treatment group while 23.4% cells death occurred in AzaC pre treatment group. After 48h MCF7 cells treated with Dox showed 19.0% cell death while AzaC sensitized cells showed 50.0% cells death when exposed to 500 nM of Dox for 48h. Western blot analysis showed the upregulations in the expression of bax, caspase-3, caspase-9 and p53 in AzaC-sensitized MCF7 cells treated with Dox as compared to those treated with only Dox. There was no clear indication for pro-apoptosis genes in the cells treated with individual drugs. These results showed that pretreatment with the epigenetic modulator significantly increased the sensitivity of MCF7 cells to Dox. Therefore it is concluded that demethylation event might enhance the activity of DNA intercalating agents to induce DNA damage in breast cancer cells.