Studies on the Role of TGF-β1/TGF-βR1/Smad4 In the Occurance and Development of Myelocytic Leukemia and Breast Cancer

Abstract 4714

Previous studies showed that the function of TGF-β/Smad passway is aberrant in many human cancers, the expresses of TGF-β1, TGF-βR1 and Smad4 proteins were related to the clinicopathologic characteristic of tumors and prognosis. The aim of the present work was to study the role of TGF-β1, TGF-βR1 and Smad4 in the occurance and development of myelocytic leukemia and breast cancer. Firstly, 2 myelocytic leukemia cell lines (KG1, HL60), 2 breast cancer cell lines (SKBR-3, MCF-7) and 293 cells (normal control) were selected. Secondly, we detected the expression levels of mRNA and protein in the 4 cell lines by fluorescence quantitative PCR (qRT-PCR), immunohistochemistry, and Western blotting. qRT-PCR showed that the gene copies of TGF-β1, TGF-βR1 and Smad4 in SKBR-3 cells and KG1 cells, which were poorly differentiated, were lower than that in MCF-7 cells and HL60 cells, which were well differentiated (P<0.01); and the gene copies in 293 cells were higher than all of the four cell lines (P<0.01). Western blotting showed that the protein expression levels of TGF-β1, TGF-βR1 and Smad4 in SKBR-3 and KG1 cells were also lower than in MCF-7 cells and HL60 cells (P<0.01), and higher in 293 cells (P<0.01). The same results could also be abtained by immunohistochemistry. This studies may indicate that TGF-β1, TGF-βR1 and Smad4 act possibly as the role of anti-oncogene in myelocytic leukemia and breast cancer, which also may be associated with the biological behaviors of the development of myelocytic leukemia and breast cancer. TGF-β/Smad passway might be a promising candidate target for the controling progression of malignant tumor.