Large-scale drug sensitivity, gene dependency, and proteogenomic analyses of telomere maintenance mechanisms in cancer cells

Replicative immortality is a hallmark of cancer, driven by the activation of telomere maintenance mechanisms, that is yet to be therapeutically exploited. To expedite discoveries that will enable the development of therapeutics that target telomere maintenance mechanisms, this study provides a resource of telomere biology metrics for a pan-cancer panel of 976 cell lines. We generate proteomic data from data-independent-acquisition mass spectrometry for most of these cell lines and integrate pre-existing multi-omic, drug sensitivity, and molecular dependency data from CRISPR/Cas9 knock-out screens. The data illustrate a broad range and heterogeneity in telomere biology, including states that diverge from the binary model of telomere maintenance activation involving either telomerase or the Alternative Lengthening of Telomeres mechanism. Using the telomere biology metrics and multi-omic data, we derive proteomic and transcriptomic predictors of Alternative Lengthening of Telomeres and telomerase activity levels. Our investigations also reveal molecular vulnerabilities associated with the Alternative Lengthening of Telomeres mechanism and drug sensitivity correlating with telomerase activity levels. These findings illustrate opportunities for leveraging this resource to realize the potential for telomere biology-directed cancer therapeutics and companion diagnostics.