The BCL2 antagonist of cell death pathway influences endometrial cancer cell sensitivity to cisplatin.
OBJECTIVE
To identify pathways that influence endometrial cancer (EC) cell sensitivity to cisplatin and to characterize the BCL2 antagonist of cell death (BAD) pathway as a therapeutic target to increase cisplatin sensitivity.


METHODS
Eight EC cell lines (Ishikawa, MFE296, RL 95-2, AN3CA, KLE, MFE280, MFE319, HEC-1-A) were subjected to Affymetrix Human U133A GeneChip expression analysis of approximately 22,000 probe sets. In parallel, endometrial cell line sensitivity to cisplatin was quantified by MTS assay, and IC(50) values were calculated. Pearson's correlation test was used to identify genes associated with response to cisplatin. Genes associated with cisplatin responsiveness were subjected to pathway analysis. The BAD pathway was identified and subjected to targeted modulation, and the effect on cisplatin sensitivity was evaluated.


RESULTS
Pearson's correlation analysis identified 1443 genes associated with cisplatin resistance (P<0.05), which included representation of the BAD-apoptosis pathway. Small interfering RNA (siRNA) knockdown of BAD pathway protein phosphatase PP2C expression was associated with increased phosphorylated BAD (serine-155) levels and a parallel increase in cisplatin resistance in Ishikawa (P=0.004) and HEC-1-A (P=0.02) cell lines. In contrast, siRNA knockdown of protein kinase A expression increased cisplatin sensitivity in the Ishikawa (P=0.02) cell line.


CONCLUSIONS
The BAD pathway influences EC cell sensitivity to cisplatin, likely via modulation of the phosphorylation status of the BAD protein. The BAD pathway represents an appealing therapeutic target to increase EC cell sensitivity to cisplatin.
Department of Women's Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612, USA.
Hye Sook
HS
Chon
Douglas C
DC
Marchion
Yin
Y
Xiong
Ning
N
Chen
Elona
E
Bicaku
Xiaomang Ba
XB
Stickles
Nadim
N
Bou Zgheib
Patricia L
PL
Judson
Ardeshir
A
Hakam
Jesus
J
Gonzalez-Bosquet
Robert M
RM
Wenham
Sachin M
SM
Apte
Johnathan M
JM
Lancaster
D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology; D045744:Cell Line, Tumor; D002945:Cisplatin / Q000494:pharmacology*; D019008:Drug Resistance, Neoplasm; D018274:Electroporation; D016889:Endometrial Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D010766:Phosphorylation; D034741:RNA, Small Interfering / Q000008:administration & dosage / Q000235:genetics; D015398:Signal Transduction; D051025:bcl-Associated Death Protein / Q000235:genetics / Q000378:metabolism*
D000970:Antineoplastic Agents; C494819:BAD protein, human; D034741:RNA, Small Interfering; D051025:bcl-Associated Death Protein; D002945:Cisplatin