Ankyrin Repeat Domain 1, ANKRD1, a Novel Determinant of Cisplatin Sensitivity Expressed in Ovarian Cancer

Westmead Institute for Cancer Research, University of Sydney at the Westmead Millennium Institute, Westmead Hospital, Westmead, NSW, Australia.
Clinical Cancer Research (Impact Factor: 8.19). 11/2008; 14(21):6924-32. DOI: 10.1158/1078-0432.CCR-07-5189
Source: PubMed

ABSTRACT The standard of care for ovarian cancer includes platinum-based chemotherapy. It is not possible, however, to predict clinical platinum sensitivity or to design rational strategies to overcome resistance. We used a novel approach to identify altered gene expression associated with high sensitivity to cisplatin, to define novel targets to sensitize tumor cells to platins and ultimately improve the effectiveness of this widely used class of chemotherapeutics.
Using differential display PCR, we identified genes differentially expressed in a mutagenized cell line with unusual sensitivity to cisplatin. The most highly differentially expressed gene was selected, and its role in determining cisplatin sensitivity was validated by gene transfection and small interfering RNA (siRNA) approaches, by association of expression levels with cisplatin sensitivity in cell lines, and by association of tumor expression levels with survival in a retrospective cohort of 71 patients with serous ovarian adenocarcinoma.
The most highly differently expressed gene identified was ANKRD1, ankyrin repeat domain 1 (cardiac muscle). ANKRD1 mRNA levels were correlated with platinum sensitivity in cell lines, and most significantly, decreasing ANKRD1 using siRNA increased cisplatin sensitivity >2-fold. ANKRD1 was expressed in the majority of ovarian adenocarcinomas tested (62/71, 87%), and higher tumor levels of ANKRD1 were found in patients with worse outcome (overall survival, P=0.013).
These findings suggest that ANKRD1, a gene not previously associated with ovarian cancer or with response to chemotherapy, is associated with treatment outcome, and decreasing ANKRD1 expression, or function, is a potential strategy to sensitize tumors to platinum-based drugs.

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    • "Ankyrin repeats is a short motif that mediates protein – protein interactions and found in proteins of diverse function, and ankyrin-repeat proteins such as p16 (Tang et al, 2003) and Notch proteins (Aster et al, 2000) have been associated with cancer. Furthermore, up-regulation of ANKRD1 was associated with decreased sensitivity for cisplatin in ovarian adenocarcinoma (Scurr et al, 2008). In addition to our data, ankyrin-repeat domains may enhance platinum resistance. "
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