RNAi screening of the kinome identifies modulators of cisplatin response in ovarian cancer cells.
OBJECTIVE
Ovarian cancer retains a poor prognosis among the female gynaecological malignancies. It constitutes about 3% of all malignancies in women and accounts for 5% of all female cancer related deaths. A standard treatment is cytoreductive surgery followed by adjuvant chemotherapy, and re-treatment with platinum based chemotherapy at the time of relapse. In order to improve cisplatin response in ovarian cancer cells, we utilized a high-throughput RNAi screening to identify kinase modulators.


METHODS
A high-throughput RNAi screen was performed using a siRNA library targeting 572 kinases to identify potentiators of cisplatin response in the ovarian cancer cell line SKOV3.


RESULTS
RNAi screening identified at least 55 siRNAs that potentiated the growth inhibitory effects of cisplatin in SKOV3 cells. Inhibition of ATR and CHK1 resulted in the greatest modulation of cisplatin response. Drug dose response of cisplatin in the presence of siRNA validated the effects of these target genes. To show that the siRNA data could be successfully translated into potential therapeutic strategies, CHK1 was further targeted with small molecule inhibitor PD 407824 in combination with cisplatin. Results showed that treatment of SKOV3 and OVCAR3 cells with CHK1 inhibitor PD 407824 led to sensitization of ovarian cancer cells to cisplatin.


CONCLUSIONS
Our data provides kinase targets that could be exploited to design better therapeutics for ovarian cancer patients. We also demonstrate the effectiveness of high-throughput RNAi screening as a tool for identifying sensitizing targets to known and established chemotherapeutic agents.
Arora
Shilpi
S
Pharmaceutical Genomics Division, The Translational Genomics Research Institute, Scottsdale, AZ 85259, USA.
Bisanz
Kristen M
KM
Peralta
Lourdes A
LA
Basu
Gargi D
GD
Choudhary
Ashish
A
Tibes
Raoul
R
Azorsa
David O
DO
D000970:Antineoplastic Agents / Q000494:pharmacology*; D002227:Carbazoles / Q000494:pharmacology; D053148:Caspase 3 / Q000378:metabolism; D053179:Caspase 7 / Q000378:metabolism; D048708:Cell Growth Processes / Q000187:drug effects; D045744:Cell Line, Tumor; D000071877:Checkpoint Kinase 1; D002945:Cisplatin / Q000494:pharmacology*; D005260:Female; D006801:Humans; D010051:Ovarian Neoplasms / Q000188:drug therapy* / Q000201:enzymology* / Q000235:genetics; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D011494:Protein Kinases / Q000235:genetics* / Q000378:metabolism; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics
D000970:Antineoplastic Agents; D002227:Carbazoles; C544549:PD 407824; D047428:Protein Kinase Inhibitors; D034741:RNA, Small Interfering; D011494:Protein Kinases; C000605867:CHEK1 protein, human; D000071877:Checkpoint Kinase 1; D053148:Caspase 3; D053179:Caspase 7; D002945:Cisplatin