WRN and cancer: It is noteworthy, that the depletion of the related RecQ helicase BLM significantly impaired viability of hTERT RPE-1, but not HCT 116 cells. These RNAi experiments demonstrate that depletion of WRN abrogates viability in MSI-H but not MSS or non-transformed cells. To assess a potential mechanism to bypass WRN dependence in MSI-H cancer cells, we tested whether co-depletion of p53 and WRN in the TP53-wild-type MSI-H CRC line HCT 116 would reverse the sensitivity to WRN knock-down.