We have previously shown that Bcl-xL promotes lymph node metastasis of primary panNETs in the RIP-Tag; RIP-tva mouse model, which faithfully models multiple steps of tumour development in human cancer and allows for genetic alterations to be introduced into premalignant lesions by infection with avian retroviral vector, RCASBP12. This evidence concerns the gene BCL2L1 and infection.