Effects Of Cytoplasmic M-csf On The Sensitivity Of Anti-tumor Chemotherapeutic Drug In Human Breast Cancer

OBJECTIVES: To explore mechanism and effects of cytoplasmic M-CSF on the sensitivity of anti-tumor chemotherapeutic drug in human breast cancer cells.METHODS: The effect of cytoplasmic M-CSF on the sensitivity of anti-tumor chemotherapeutic drug of MCF-7 cells was analyzed by MTT and trypan blue staining. The concentration of adriamycin(ADM) and paclitaxel(TAX)within MCF-7 cells was measured by high efficiency fluid chromatography(HPLC). The expression of P-gp and Bcl-2 protein was detected by Western blot. The expression of MDR1 gene was assayed by RT-PCRRESULTS: The results from MTT and trypan blue staining indicated that the relative survival rate of pCMV/cyto/myc-M-CSF-transfected MCF-7 cells(referred as to MCF-7-M cell) is higher than either pCMV/cyto/myc transfected MCF-7 cells (referred as to MCF-7-C cell) or untransfected MCF-7 cells (referred as to MCF-7 cell), There was no significant difference between that of MCF-7-C cells and MCF-7 cells(p>0.05).The results from HPLC showed that there was less ADM and TAX within MCF-7-M cells than either MCF-7-C and MCF-7 cell line(p<0.01). Our results indicated that MCF-7-M cell had a higher expresion of MDR1gene , Bcl-2 and P-gp protein , compared with MCF-7-C and MCF-7 cell line(p<0.01).CONCLUSION: Cytoplasmic M-CSF enhances the resistance of MCF-7 cell to ADM and TAX and reduces the concentration of these two drugs within MCF-7 cell. Cytoplasmic M-CSF up-regulates the expression of Bcl-2 and P-gp protein and MDR gene in MCF-7 cells.