BCL2 and deltaretrovirus infections: Moreover, the regulation of anti-apoptotic pathways in the context of HTLV infection and ATLL was examined by Nicot, C. et al. The findings showed that both HTLV-I and HTLV-II strongly upregulate the expression of the BCL-2 family member BCL-xL in infected T cells, both in vitro and in ex vivo ATLL patient samples [26].