cellules souches du cancer (CCM) sont impliqués dans la rechute de la tumeur en raison de la chimiorésistance. Nous avons optimisé un protocole pour la sélection et l'expansion de la CCF de lignées cellulaires de cancer de l'ovaire. En traitant les cellules avec le cisplatine chimiothérapeutique et la mise en culture d'une cellule souche promotion de médias nous enrichir en cultures SCC non adhérentes.
cellules souches du cancer (CCM) sont définies comme un sous-ensemble du cyclisme lente et cellules indifférenciées qui se divisent de façon asymétrique pour générer hautement proliférante, envahissante, et les cellules tumorales chimiorésistantes. Par conséquent, les CSC sont une population intéressante de cellules à cibler thérapeutique. CCM sont prédits pour contribuer à un certain nombre de types de tumeurs malignes, y compris celles dans le sang, le cerveau, les poumons, le tractus gastro-intestinal, de la prostate et de l'ovaire. Isoler et enrichir une population de cellules tumorales pour les CSC permettra aux chercheurs d'étudier les propriétés, la génétique, et la réponse thérapeutique des CSC. Nous avons généré un protocole qui enrichit de manière reproductible pour CCM de cancer ovarien de lignées cellulaires de cancer de l'ovaire (SKOV3 et OVCA429). Les lignées cellulaires sont traitées avec 20 uM de cisplatine pendant 3 jours. Les cellules survivantes sont isolées et mises en culture dans un milieu de cellules souches sans sérum contenant des cytokines et des facteurs de croissance. Nous démontrons un enrichissement de ces CSC purifiés par l'analyse des cellules isolées pour known marqueurs de cellules souches Oct4, Nanog, et PROM1 (CD133) et de l'expression de surface cellulaire de CD177 et CD133. L'exposition CSC a augmenté chimiorésistance. Cette méthode pour l'isolement des CSC est un outil utile pour étudier le rôle des CSC dans la chimiorésistance et la tumeur récidive.
Resistance to chemotherapy is a major impediment to the treatment and cure of cancer. Ovarian cancer is the 5th leading cause of cancer-related deaths among women in the United States (American Cancer Society Facts and Figures 2013). Patients initially respond well to chemotherapy, but most patients relapse1. After relapse patients are treated with a variety of additional chemotherapy agents with very little benefit2. General properties of CSCs include unlimited proliferative capabilities, retention of an undifferentiated state, resistance to drug treatment, efficient DNA repair, and ability to generate malignant tumor cells with different phenotypes3. CSCs frequently exhibit expression of stem cell genes such as Nanog, Oct4, Sox2, Nestin, CD133, and CD117. CSCs often express elevated levels of ABCG2, and ALDH genes that may contribute to drug efflux and metabolism3,4.
The first definitive evidence for CSCs was demonstrated by isolating acute myeloid leukemia-initiating cells that were capable of self-renewal and tumor generation5. These leukemic stem cells expressed surface CD34 and generated leukemia in NOD/SCID (immunocompromised) mice5. Since then CSCs have been identified in many cancer types including leukemias/lymphomas, breast, bladder, colorectal, endometrial, sarcomas, hepatocellular carcinoma, melanomas, gliomas, ovarian, pancreatic, prostate, squamous cell carcinoma, and lung6. Therefore, being able to study this subtype of cancer cell is advantageous.
The goal of this study is to create a protocol for the selection and isolation of chemoresistant CSCs. Several methods have been reported for the isolation of CSCs from ovarian cancer cell lines. Non-adherent spheroids isolated from OVCAR-3, SKOV3, or HO8910 cultures demonstrate stem-like properties7,8. Isolation of CD133+ cells from OVCAR-3 cultures also yields CSCs. CSCs have also been selected in culture by treatment with chemotherapeutic agents. Treating tumor cell lines (OVCA433, Hey, and SKOV3 cells) with cisplatin and paclitaxel allows for the expansion and isolation of CSCs4,9. While culture of some cell types in CSC media leads to isolation of CSCs, SKOV3 cells did not survive culture in serum-free media or form sphere cells4. Therefore, treatment of cells with cisplatin and paclitaxel aided the expansion or isolation of this population4.
Using a modification of the procedure presented by Ma and colleagues4 we developed a method to isolate CSCs from the ovarian cancer cell lines. Our protocol is advantageous as it yields more viable cells while using less toxic chemotherapeutic agents. Cells are treated with cisplatin and subsequently grown in serum-free media supplemented with growth factors (stem cell media). We isolate the resulting non-adherent sphere cells and assay them for their expression of stem cell markers. This model enables the study of CSC properties and response to drug therapy.
CSC qui sont résistantes à la thérapie peuvent être tenus responsables de rechute après le traitement de la tumeur primitive. Caractérisation des CSC peut conduire à l'amélioration des thérapies pour le cancer de l'ovaire. Les paramètres critiques dans la mise en place de CCF chimiorésistantes utilisant le protocole ci-dessus sont des chronogrammes de la durée du traitement avec la chimiothérapie et la concentration de la chimiothérapie. Lorsque vous utilisez le protocole de Ma et al. il a…
The authors have nothing to disclose.
Serene Samyesudhas and Dr. Lynn Roy assisted in preparing samples for filming.
Name of Reagent/ Equipment | Company | Catalog Number | Comments/Description |
McCoy | Life Technologies | 16600-108 | Warm to 37C prior to use |
DMEM / F12 serum free | Life Technologies | 11320-033 | Warm to 37C prior to use |
Minimal Essential Media | Life Technologies | 42360032 | Warm to 37C prior to use |
Sodium Pyruvate | Life Technologies | 11360070 | |
Polybrene | Millipore | TR-1003-G | |
Blasticidin | Life Technologies | R21001 | |
Fetal Bovine Serum | Atlas Biologicals | F-0500-A | |
Penicillin-streptomycin | Life Technologies | 15070-063 | |
Cisplatin | Sigma-Aldrich | T7402-5MG | Caution: Toxic Use precautions |
pLenti-suCMV-Rsv | Gentarget | LVP023 | BSL2 approval needed |
Insulin | Sigma-Aldrich | I-1882 | |
Human Recombinant EGF | Cell Signaling Technology | 8916LC | |
bFGF | BD biosciences | 354060 | |
LIF | Santa Cruz | sc-4988A | |
Bovine Serum Albumin | Roche | 03 116 956 001 | |
TRIzol | Life Technologies | 15596-018 | |
High Capacity cDNA Reverse Transcription Kit | Applied Biosystems | 4368813 | |
IQ Multiplex Powermix | BioRad | 1725849 | |
Accumax | Millipore | ||
Primers | Integrated DNA Technology | individually designed and ordered (see protocol for sequnces) | |
Anti-CD133 PE | Milenyl | 130-098-826 | Primer/probe sets are light sensitive |
CD117-Biotin | Miltenly | 130-098-570 | |
AntiBiotin-FITC | Miltenly | 130-098-796 | |
Paraformaldehyde | Sigma-Aldrich | P6148-1KG | Caution: Toxic always prepare in hood and make fresh. |
Trypsin | Life Technologies | 25300062 | |
MTT (3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) | Sigma-Aldrich | 25200-072 | |
EVOS Fl Epifluorescence and Transmitted Light Microscope | Advanced Microscopy Group | ||
Biorad CFX96 C1000 System | Biorad | ||
Beckman Coulter FC500 Flow Cytometer | Beckman Coulter | ||
Spectramax 340PC384 | Molecular Devices |