**3. Conclusion**

CSC are rare cells and they are distinct from other bulk tumor cells. They generate the tumor and maintain the tumor hetrogenity. If the CSCs are elemiminated/differentiated to nonCSCs then cancer can be eradicated. The CSC niche maintains the CSC characteristics and increases the CSC potential, hence CSC niche offers a critical window treatment of cancer. Hence strategies that target the pathways critical for selfrenewal which are maintained through niche should be the focus of therapy. Notch, Wnt and Hedgehog pathways are known for maintaining self renewal of normal stem cells (Merchant and Matsui, 2010; Pannuti *et al.*, 2010; Takahashi-Yanaga and Kahn, 2010). These pathways offers targets in combination of other tumor specific markers for CSC targeting. For eg. Farnie, G et al., demonstrated that inhibiting notch signaling using gama secretase inhibitors in DCIS derived cells decreases their mamosphere forming efficiency (Farnie *et al.*, 2007). Further antibodies against the ECM Protein fibronectin receptor α4β1 integrin prevented the interaction of cancer cells with premetastatic niches and reduce the minimal residual disease (Kaplan *et al.*, 2005). Moreover antibodies to fibronectin and β1 integrin promoted epithelial phenotype of invasive breast cancer cells in organotypic three dimentional cultures (Sandal *et al.*, 2007). Hence when formulating such therapeutic modalities a combination of inhibitors/biomolecules which can efficiently inhibit the cancer stem cells self renewal should be considered.

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