Characterization of a stem cell population in lung cancer A549 cells.
We isolated a stem cell subpopulation from human lung cancer A549 cells using FACS/Hoechst 33342. This side population (SP), which comprised 24% of the total cell population, totally disappeared after treatment with the selective ABCG 2 inhibitor fumitremorgin C. In a repopulation study, isolated SP and non-SP cells were each able to generate a heterogeneous population of SP and non-SP cells, but this repopulation occurred more rapidly in SP cells than non-SP. An MTT assay and cell cycle distribution analysis reveal a similar profile between SP and non-SP groups. However, in the presence of doxorubicin (DOX) and methotrexate (MTX), SP cells showed significantly lower Annexin V staining when compared to non-SP cells. Taken together, these results demonstrate that SP cells have an active regeneration capacity and high anti-apoptotic activity compared with non-SP cells. Furthermore, our GeneChip data revealed a heightened mRNA expression of ABCG2 and ABCC2 in SP cells. Overall these data explain why the SP of A549 has a unique ability to resist DOX and MTX treatments. Therefore, we suggest that the expression of the ABCG2 transporter plays an important role in the multidrug resistance phenotype of A549 SP cells.
Sung
Ji-Min
JM
Department of Veterinary Pharmacology and Toxicology, College of Veterinary Medicine, Konkuk University, Hwayang-dong 1, Kwangjin-gu, Seoul 143-701, Republic of Korea.
Cho
Hee-Jung
HJ
Yi
Hee
H
Lee
Chi-Ho
CH
Kim
Hye-Sun
HS
Kim
Dong-Ku
DK
Abd El-Aty
A M
AM
Kim
Jin-Suk
JS
Landowski
Christopher P
CP
Hediger
Matthias A
MA
Shin
Ho-Chul
HC
D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism; D000970:Antineoplastic Agents / Q000494:pharmacology; D017209:Apoptosis; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D004317:Doxorubicin / Q000494:pharmacology; D018432:Drug Resistance, Multiple; D019008:Drug Resistance, Neoplasm; D015870:Gene Expression; D006801:Humans; D008175:Lung Neoplasms / Q000378:metabolism / Q000473:pathology*; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism; D008727:Methotrexate / Q000494:pharmacology; D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000235:genetics / Q000378:metabolism; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism; D014411:Neoplastic Stem Cells / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*
D000070997:ATP Binding Cassette Transporter, Subfamily G, Member 2; D018528:ATP-Binding Cassette Transporters; D000970:Antineoplastic Agents; D004317:Doxorubicin; D026901:Membrane Transport Proteins; D008727:Methotrexate; D000089762:Multidrug Resistance-Associated Protein 2; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D009363:Neoplasm Proteins; C000715087:ABCC2 protein, human; C116614:ABCG2 protein, human