ABSTRACT
Accumulating evidences have demonstrated that there are several markers that can be used to recognize cancer stem cell, such as cell surface marker, enzymatic marker,gene expression marker and some functional markers. Cancer stem cell is characterized by multidrug resistance, enhanced DNA repair and antiapoptotic ability ,and some in vivo niche features that may make cancer cells resistant to conventional therapy.The increasing understanding of aberrantly expressed molecules and signaling pathways in TSC may provide the theoretical foundation for designing of target therapeutic strategies for TSC.
ABSTRACT
In clinical it has been demonstrated that a lot of malignant tumors exist over-expression of the epidermal growth factor receptor (EGFR) , and the phenomena in the breast cancer which is resistante to Tamoxifen(TAM-R) is associated with poor survival. It is very important to understand the underlying mechanisms of EGFR in the TAM-R breast cancer, and major efforts are now being made to overcome the condition.In some preclinical trials,it has been proved that mechanisms of tamoxifen resistance to endocrine therapy is associated with EGFR signaling activity in hormone-dependent breast cancer cells. There have been reports of the inhibitors to prevent EGFR signaling to treatment of the TAM-R breast cancer in clinical. However, the clinical data demonstrated that not all patients responded to the inhibitor therapy, indicating the existence of an intrinsic or de novo resistance to the drug, which is a new problem.