Kreft stamceller (cscs) er involvert i tumor tilbakefall på grunn chemoresistance. Vi har optimalisert en protokoll for utvalg og utvidelse av cscs fra eggstokkreft cellelinjer. Ved behandling av cellene med det kjemoterapeutiske cisplatin og dyrkning i en stamcelle fremme medier vi berike for ikke-adherente CSC kulturer.
Cancer stamceller (cscs) er definert som en undergruppe av langsom sykling og udifferensierte celler som deler seg asymmetrisk å generere svært proliferativ, invasiv og kjemoresistent tumorceller. Derfor cscs er en attraktiv populasjon av celler å målrette terapeutisk. Cscs er spådd å bidra til en rekke typer av maligniteter, inkludert de i blod, hjerne, lunge, mage-tarmkanalen, prostata og ovarier. Isolere og berikende en svulst celle befolkning for cscs vil gjøre forskere til å studere egenskaper, genetikk og terapeutisk respons av cscs. Vi ga en protokoll som reproduserbart beriker for eggstokkreft cscs fra eggstokkreft cellelinjer (SKOV3 og OVCA429). Cellelinjer blir behandlet med 20 mM cisplatin i 3 dager. Overlevende celler er isolert og dyrket i et serumfritt medium inneholdende stamcelle cytokiner og vekstfaktorer. Vi demonstrerer en berikelse av disse rensede cscs ved å analysere de isolerte celler for known stamcellemarkører Oct4, Nanog, og Prom1 (CD133) og celleoverflaten uttrykk for CD177 og CD133. Den cscs utstillings økt chemoresistance. Denne metoden for isolering av cscs er et nyttig verktøy for å studere rollen cscs i chemoresistance og tumor tilbakefall.
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.
Cscs som er resistente mot behandling kan være ansvarlig for tilbakefall etter behandling av primærtumor. Karakterisering av cscs kan føre til bedre behandling for eggstokkreft. De kritiske parametre i etableringen av kjemoresistent cscs ved hjelp av ovennevnte protokoll er timingen lengden av behandling med kjemoterapi og konsentrasjonen av kjemoterapi. Ved bruk av protokollen i Ma et al. det ble funnet at etter 7 dagers behandling med cisplatin og paclitaxel, ingen levedyktige celler forble 4. V…
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 |