CCL3 and cancer: Overall, the engineered LLO strains generated production of beneficial cytokines and chemokinesfor altering the TME including TNF-α and IL-12p40,,, but the pleiotropic effectsof cytokines and chemokines such as IL-6 and MCP-1 add ambiguity asboth are implicated in promoting T cell invasion into the TME butcan also promote tumor angiogenesis when expressed by cancer cells., Yet, the LLO-SK strain did downregulate some cytokinesand chemokines implicated in poor tumor outcomes such as MIP-1α,MIP-2, G-CSF, and IL-10 which is beneficial.,−, ,