| Tsai T, Hong RL, Tsai JC, Lou PJ, Ling IF, Chen CT |
------>authors3_c=None ------>paper_class1=1 ------>Impact_Factor=None ------>paper_class3=2 ------>paper_class2=1 ------>vol=34 ------>confirm_bywho=curator ------>insert_bywho=tmtsai00 ------>Jurnal_Rank=None ------>authors4_c=None ------>comm_author= ------>patent_EDate=None ------>authors5_c=None ------>publish_day=None ------>paper_class2Letter=None ------>page2=72 ------>medlineContent= ------>unit=F0400 ------>insert_date=20031016 ------>iam=1 ------>update_date= ------>author=??? ------>change_event=5 ------>ISSN=None ------>authors_c=None ------>score=500 ------>journal_name=Lasers in Surgery & Medicine ------>paper_name=Effect of 5-aminolevulinic acid-mediated photodynamic therapy on MCF-7 and MCF-7/ADR cells ------>confirm_date=20040422 ------>tch_id=084014 ------>pmid=14755426 ------>page1=62 ------>fullAbstract=BACKGROUND AND OBJECTIVES: Photodynamic therapy (PDT) has been proposed as an alternative approach in overcoming multidrug resistance (MDR) phenotype. To verify whether 5-aminolevulinic acid (ALA)-mediated PDT is effective in MDR cells, we studied the protoporphyrin IX (PpIX) content, intracellular localization, and phototoxicity in human breast cancer cells MCF-7 and derived MDR subline, MCF-7/ADR. STUDY DESIGN/MATERIALS AND METHODS: The fluorescence kinetics of ALA-induced PpIX was evaluated by spectrofluorometer. The phototoxicity of MCF-7 and MCF-7/ADR cells was determined by tetrazolium (MTT) assays and clonogenic assay. Furthermore, Annexin V and propidium iodide (PI) binding assays were performed to analyze the characteristics of cell death after ALA-PDT. RESULTS: MCF-7/ADR accumulated a lower level of PpIX as compared to parental MCF-7 cells. Significant phototoxicity was observed in MCF-7 and increased in a fluence-dependent manner with LD(50) around 8 J/cm(2). Compared to its parental counterpart, MCF-7/ADR cells were less sensitive to ALA photodynamic treatment and PDT-induced cytotoxicity did not increase in a dose responsive manner as the concentration of ALA increased or the fluence of light increased. ALA-PDT was less effective for MCF-7/ADR cells than MCF-7 cells even under the condition when these two cell lines contained the similar amounts of PpIX. CONCLUSIONS: These results indicate that, except for the MDR related characteristics, MCF-7/ADR cells might possess intrinsic mechanisms that render them less sensitive to ALA-PDT induced phototoxicity. ------>tmu_sno=None ------>sno=7743 ------>authors2= ------>authors3= ------>authors4= ------>authors5= ------>authors6= ------>authors6_c=None ------>authors=Tsai T, Hong RL, Tsai JC, Lou PJ, Ling IF, Chen CT ------>delete_flag=0 ------>SCI_JNo=None ------>authors2_c=None ------>publish_area=None ------>updateTitle=Effect of 5-aminolevulinic acid-mediated photodynamic therapy on MCF-7 and MCF-7/ADR cells. ------>language=2 ------>check_flag= ------>submit_date= ------>country=None ------>no= ------>patent_SDate=None ------>update_bywho= ------>publish_year=2004 ------>submit_flag= ------>publish_month=None |