The dual role of dopamine and serotonin in cancer progression and inflammation: Mechanisms and therapeutic potential.

This review examines the critical functions of dopamine and serotonin in the regulation of inflammation and cancer, emphasizing their potential as therapeutic targets. Traditionally recognized for their roles in neural communication, these neurotransmitters are now understood to play substantial roles in immune modulation and tumor progression. We conducted a systematic review of studies published between 2013 and 2024, using databases such as PubMed, Google Scholar, and Scopus, to assess dopamine and serotonin synthesis, receptor activity, and involvement in disease pathways. Findings indicate that dopamine, through its D1 and D2 receptors, exerts both pro- and anti-inflammatory effects, influencing tumor growth and immune responses in cancers such as breast and pancreatic. Similarly, serotonin, particularly through receptors HTR2A and HTR2B, has demonstrated dual roles in cancer progression, impacting the growth and metastasis of cancers such as gastric and colorectal. This review also addresses the interaction between dopamine and serotonin signaling pathways, which may collectively alter immune cell function and tumor microenvironment dynamics, suggesting a promising direction for combined therapeutic approaches. By synthesizing current data on dopamine and serotonin pathways, this review aims to inform the development of targeted therapies that modulate immune responses in inflammation-driven cancers. Our findings underscore the potential of neurotransmitter-based interventions as a novel strategy for managing cancer and inflammatory diseases.