Mitochondrial proteomic analysis of cisplatin resistance in ovarian cancer.
Epithelial ovarian cancer (EOC) is the leading cause of death among women with gynecologic malignancies and accounts for approximately 6% of cancer deaths among women. Cisplatin and its analogues form the backbone of the most active chemotherapy regimens in advanced EOC; however, development of platinum resistance is common and typically marks a transition in which curing the patient is no longer possible. An emerging theme in many cancers is that mitochondrial dysfunction contributes to an aggressive carcinogenic phenotype. We hypothesized that changes in the mitochondrial proteome are required to support development of cisplatin resistance in human EOC. To investigate this hypothesis, an organellar proteomics approach was utilized to quantify alterations in protein abundance in mitochondria enriched from isogenic cisplatin-sensitive (A2780) and -resistant (A2780-CP20) human EOC cells. Protein isolates from mitochondria-enriched fractions were analyzed by high resolution liquid chromatography-tandem mass spectrometry (LC-MS/MS), and relative abundance of identified proteins was quantified by spectral counting. Pathway analyses revealed significant increases in notch signaling pathways, cell survival, and alternate apoptotic pathways in the A2780-CP20 subtype. Among the alterations identified in the mitochondrial proteomic composition in cisplatin-resistant EOC cells, activated leukocyte cell adhesion molecule (AKAP12) and A kinase anchoring protein 12 (AKAP12) were elevated, while nestin was diminished in the mitochondrial fraction of A2780-CP20 relative to A2780. This was verified by immunoblot analysis. These results confirm that important changes in the mitochondrial proteome, many of which promote evasion of apoptosis and tumor invasiveness and metastasis, are present in cisplatin-resistant EOC.
Gynecologic Oncology Service, Department of Obstetrics and Gynecology, Walter Reed National Military Medical Center, Bethesda, Maryland, USA.
Nicole P
NP
Chappell
Pang-Ning
PN
Teng
Brian L
BL
Hood
Guisong
G
Wang
Kathleen M
KM
Darcy
Chad A
CA
Hamilton
G Larry
GL
Maxwell
Thomas P
TP
Conrads
D054758:A Kinase Anchor Proteins / Q000737:chemistry / Q000378:metabolism; D015703:Antigens, CD / Q000737:chemistry / Q000378:metabolism; D000970:Antineoplastic Agents / Q000494:pharmacology*; D015816:Cell Adhesion Molecules, Neuronal / Q000737:chemistry / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000737:chemistry / Q000378:metabolism; D045744:Cell Line, Tumor; D002945:Cisplatin / Q000494:pharmacology*; D019008:Drug Resistance, Neoplasm; D005260:Female; D005326:Fetal Proteins / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D015151:Immunoblotting; D007381:Intermediate Filament Proteins / Q000737:chemistry / Q000378:metabolism; D042541:Intracellular Space / Q000737:chemistry; D024101:Mitochondrial Proteins / Q000032:analysis* / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000737:chemistry / Q000378:metabolism; D064231:Nestin; D010051:Ovarian Neoplasms / Q000737:chemistry / Q000188:drug therapy* / Q000378:metabolism; D060066:Protein Interaction Maps / Q000187:drug effects; D040901:Proteomics; D015203:Reproducibility of Results; D015398:Signal Transduction / Q000187:drug effects; D013482:Superoxide Dismutase / Q000737:chemistry / Q000378:metabolism; D000099156:Superoxide Dismutase 2; D020410:Activated-Leukocyte Cell Adhesion Molecule
D054758:A Kinase Anchor Proteins; D015703:Antigens, CD; D000970:Antineoplastic Agents; D015816:Cell Adhesion Molecules, Neuronal; D018797:Cell Cycle Proteins; D002945:Cisplatin; D005326:Fetal Proteins; D007381:Intermediate Filament Proteins; D024101:Mitochondrial Proteins; D009419:Nerve Tissue Proteins; D064231:Nestin; D013482:Superoxide Dismutase; D000099156:Superoxide Dismutase 2; C491162:AKAP12 protein, human; C105613:ALCAM protein, human; D020410:Activated-Leukocyte Cell Adhesion Molecule; C577484:NES protein, human