Background: In the previous theories of cancer, they considered that cancer was a homogeneous which mean that the tumor had only tumor cells and for this reason the treatment for any tumor directed to kill these tumor cells. But, with rising of the metastatic cases of cancer patients, another theory have been raised, that the cancer is a heterogeneous disease which composed of tumor cells that previously the chemotherapy and other cancer therapies directed toward them, in addition there is another group of cells, called cancer stem cells (CSCs), these are more aggressive than the tumor cells that can force the poor microenvironment of the cancer tissue and survive and also they are undifferentiated cells so can undergo mitosis to produce more tumor cells and another group of cancer stem cells in contrast to the tumor cells, which considered a post mitotic and not divided. Objective: Demonstrate some of cancer stem cell markers that considered an important indicators of early cancer development and lately to detect cases of metastasis. Conclusion: The theory of the presence of cancer stem cells is more acceptable and applicable and so the cancer therapy must be directed to these groups of cancer stem cells.
Expression of epithelial-mesenchymal transition and cancer stem cell markers in colorectal adenocarcinoma: Clinicopathological significance
