**5. Future prospects**

Our recent study proposes to isolate or withdraw the mesenchymal-like stem cells from the MDA-MB-231 population using CD105 and other known antibody-conjugated microbeads, thus allowing for a clearer understanding of the subpopulation of the cancer cells. Potential drugs will then be applied to the isolated CD105+ (mesenchymal-like stem

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cells) and CD105- (epithelial cells) MDA-MB-231 cells. The invasion rate of the drugtreated CD105+ and CD105- MDA-MB-231 will then be determined using the Matrigel invasion assay. The mRNA and protein expression levels of the ECM degradationassociated molecules in the drug-treated CD105+ and CD105- MDA-MB-231 cells will also be assessed using real-time PCR and Western Blotting, respectively, and the gelatinase activities in the conditioned medium of drug-treated CD105+ and CD105- MDA-MB-231 cells will be investigated using ELISA. The proposed project that will utilise cell separation and isolation techniques to study the breast cancer cell invasion is a new area of cancer research in the institute of my home country. The previous research projects regarding the MDA-MB-231 cell invasion and metastasis were related to drug treatments, the effects of herbal and plant extracts, and the understanding of a gene or protein activity in cancer cells and animal models. However, the approaches to study the cancer cell invasion and metastasis by isolating or withdrawing the mesenchymal-like breast cancer cells (CD105+) from the MDA-MB-231 cell population using cell separation or isolation have not been demonstrated. Therefore, this project may establish a new fundamental cancer research and new research topic in my institute. This study may also lay a research foundation that is focused on the inhibition of invasion for the ER-negative human breast cancer cells. I also believe that, by targeting the mesenchymal-like phenotype in the MDA-MB-231 subpopulation, the invasion rate of the ER-negative human breast cancer cells can be easily monitored and controlled.
