Many disease processes result from disruption of physiologic cell signaling pathways. Cancer often develops from the loss of cell cycle regulation, while inflammatory disease results from dysregulated immune activity. Likewise, many microbial infections avoid immune clearance by interfering with cellular antimicrobial pathways. Retinoic Acid (RA) is a dynamic compound, derived from vitamin A, that can regulate various signaling pathways. RA induced cell signaling has proven beneficial against different diseases, such as Acute Promyelocytic Leukemia (APL) and psoriasis. Against APL, RA induces cellular differentiation in cancer cells to restore proper function. In psoriasis, RA downregulates inflammatory pathways, such as NF-κB. RA’s anti-inflammatory properties have also been examined in the context of sepsis, where recent animal studies have shown positive benefits. Along with regulating inflammation, RA exhibits indirect antimicrobial properties. Unlike conventional antimicrobials which target pathogens directly, RA functions as a host-directed therapy (HDT), promoting cell antimicrobial defenses. Recent studies examining RA have shown that it can improve macrophage clearance of microbial pathogens and stimulate the antiviral type-I interferon (IFN) response. RA’s effectiveness has been demonstrated against clinically relevant pathogens, such as Mycobacterium tuberculosis, Aspergillus fumigatus, and Measles virus. In this review, the therapeutic potential of RA to treat various diseases by regulating cell signaling pathways will be explored.

Retinoic Acid, Anti-inflammatory, Cell Signaling Pathways, Interferon Signaling