In both primary and KrasG12D-expressing situations, cell cycle gene signature, specifically Rb-E2F gene signature, is the top different gene signature when comparing GGCT−/− and GGCT+/+ MEFs (Table S3 and Figure S6), whereas in large T antigen-transformed situation, this Rb-E2F signature does not appear (Table S3), and this observation is in line with the fact that large T antigen is able to block Rb tumor suppressor pathway. Here, GGCT is linked to neoplasm.