Ean-Jeong Seo1, Benjamin Wiench1, Rebecca Hamm1, Malte Paulsen2, Yuangang Zu3, Yujie Fu3, Thomas Efferth4. 1. Department of Pharmaceutical Biology, Institute of Pharmacy and Biochemistry, Johannes Gutenberg University, Staudinger Weg 5, 55128 Mainz, Germany. 2. Cytometry Core Facility, Institute of Molecular Biology, Ackermannweg 4, 55128 Mainz, Germany. 3. Key Laboratory of Forest Plant Ecology, Ministry of Education, Northeast Forestry University, Hexing Road 26, 150040 Harbin, China. 4. Department of Pharmaceutical Biology, Institute of Pharmacy and Biochemistry, Johannes Gutenberg University, Staudinger Weg 5, 55128 Mainz, Germany. Electronic address: efferth@uni-mainz.de.
Abstract
UNLABELLED: Although cancer stem-like cells (CSCs) are rare, they can enter a non-proliferative or dormant state and resist therapy. Furthermore, quiescent CSCs are responsible for metastases that can appear after curative surgical treatment of a primary tumor. Because of drug resistance of CSCs, the development of novel therapies is urgently required that specifically target CSCs. PURPOSE: The aim of the present study was to investigate the potential of a panel of natural products and derivatives to inhibit CSC-enriched mammospheres of MCF-7 breast cancer cells. METHODS: CD44(high)/CD24(low) cells were identified by flow cytometry and maintained as mammospheres. As a control, we used two clinically established anticancer drugs (5-fluorouracil and docetaxel). A panel of natural products, shikonin, two cajanin stilbene acid (CSA) derivatives and artesunate were tested by resazurin assay on CSC-enriched mammospheres and MCF-7 monolayer cells. Besides, cellular shikonin uptake experiments were performed by flow cytometry. RESULTS: We found two CSA derivatives (Nos. 6 and 19) to be active cancer stem-like MCF-7 mammospheres. Especially, CSA derivative No. 19 clearly showed collateral sensitivity in mammospheres compared to monolayer cells. CONCLUSION: Phytochemicals which provoke collateral sensitivity in cancer-stem like cells are worth more detailed investigations in the future, since there is a great potential for improved chemotherapy to eradicate tumors and prolong cancer patients' survival times.
UNLABELLED: Although cancer stem-like cells (CSCs) are rare, they can enter a non-proliferative or dormant state and resist therapy. Furthermore, quiescent CSCs are responsible for metastases that can appear after curative surgical treatment of a primary tumor. Because of drug resistance of CSCs, the development of novel therapies is urgently required that specifically target CSCs. PURPOSE: The aim of the present study was to investigate the potential of a panel of natural products and derivatives to inhibit CSC-enriched mammospheres of MCF-7 breast cancer cells. METHODS:CD44(high)/CD24(low) cells were identified by flow cytometry and maintained as mammospheres. As a control, we used two clinically established anticancer drugs (5-fluorouracil and docetaxel). A panel of natural products, shikonin, two cajaninstilbene acid (CSA) derivatives and artesunate were tested by resazurin assay on CSC-enriched mammospheres and MCF-7 monolayer cells. Besides, cellular shikonin uptake experiments were performed by flow cytometry. RESULTS: We found two CSA derivatives (Nos. 6 and 19) to be active cancer stem-like MCF-7 mammospheres. Especially, CSA derivative No. 19 clearly showed collateral sensitivity in mammospheres compared to monolayer cells. CONCLUSION: Phytochemicals which provoke collateral sensitivity in cancer-stem like cells are worth more detailed investigations in the future, since there is a great potential for improved chemotherapy to eradicate tumors and prolong cancerpatients' survival times.
Authors: Ean-Jeong Seo; Ching-Fen Wu; Zulfiqar Ali; Yan-Hong Wang; Shabana I Khan; Larry A Walker; Ikhlas A Khan; Thomas Efferth Journal: Front Pharmacol Date: 2016-11-03 Impact factor: 5.810
Authors: Thomas Efferth; Mohamed E M Saeed; Elhaj Mirghani; Awadh Alim; Zahir Yassin; Elfatih Saeed; Hassan E Khalid; Salah Daak Journal: Oncotarget Date: 2017-07-25