TLR7 and papilloma: In the less severe KC tumor mouse model, TLR7−/− KC mice even tended to display a trend to shorter survival (Figure 4A), although it should be noted that many animals from this cohort had to be sacrificed for reasons unrelated to pancreatic tumorigenesis (mainly development of papillomas and lymphomas), which may be attributable to impaired restriction of endogenous retrovirus (ERV) activation as previously reported for TLR7−/− mice.31