New therapeutic targets for oral squamous cell carcinoma (OSCC) are urgently needed. We conducted genome-wide CRISPR-Cas9 screens in 21 OSCC cell lines, primarily derived from Asians, to identify genetic vulnerabilities that can be explored as therapeutic targets. We identify known and novel fitness genes and demonstrate that many previously identified OSCC-related cancer genes are non-essential and could have limited therapeutic value, while other fitness genes warrant further investigation for their potential as therapeutic targets. We validate a distinctive dependency on YAP1 and WWTR1 of the Hippo pathway, where the lost-of-fitness effect of one paralog can be compensated only in a subset of lines. We also discover that OSCCs with WWTR1 dependency signature are significantly associated with biomarkers of favourable response towards immunotherapy. In summary, we have delineated the genetic vulnerabilities of OSCC, enabling the prioritization of therapeutic targets for further exploration, including the targeting of YAP1 and WWTR1.
All main data generated or analysed during this study are included in the manuscript and supplementary files. Source data files for each figures and supplements have also been provided.The larger datasets of CRISPR screens, WES and RNA-sequencing output are available from Figshare (https://doi.org/10.6084/m9.figshare.11919753).
This work was directly supported by the Newton-Ungku Omar Fund and the Medical Research Council, United Kingdom (MR/P013457/1). Authors in S.C.C.'s group were supported by sponsors of Cancer Research Malaysia; Authors in M.J.G's group were supported by Wellcome. Other funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
© 2020, Chai et al.
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