PT  - JOURNAL ARTICLE
AU  - Katharina I. Deeg
AU  - Inn Chung
AU  - Caroline Bauer
AU  - Karsten Rippe
TI  - Cancer cells with alternative lengthening of telomeres do not display a general hypersensitivity to ATR inhibition
AID  - 10.1101/053280
DP  - 2016 Jan 01
TA  - bioRxiv
PG  - 053280
4099  - http://biorxiv.org/content/early/2016/06/03/053280.short
4100  - http://biorxiv.org/content/early/2016/06/03/053280.full
AB  - Telomere maintenance is a hallmark of cancer as it provides cancer cells with cellular immortality. A significant fraction of tumors uses the alternative lengthening of telomeres (ALT) pathway to elongate their telomeres and to gain an unlimited proliferation potential. Since the ALT pathway is unique to cancer cells, it represents a potentially valuable, currently unexploited target for anticancer therapies. Recently, it was proposed that ALT renders cells hypersensitive to ataxia telangiectasia-and RAD3-related (ATR) protein inhibitors (Flynn et al., Science 347, 273).Here, we measured the response of various ALT or telomerase positive cell lines to the ATR inhibitor VE-821. In addition, we compared the effect of the inhibitor on cell viability in an isogenic cell line, in which ALT was active or suppressed. In these experiments a general ATR inhibitor sensitivity of cells with ALT could not be confirmed. We rather propose that the observed variations in sensitivity reflect differences between cell lines that are unrelated to ALT.