Melatonin at the Crossroads of Oxidative Stress, Immunity, and Cancer Therapy

Area of Science:

• Biochemistry
• Immunology
• Cancer Biology

Background:

• Melatonin is an evolutionarily conserved indolamine with known roles in redox homeostasis and circadian rhythms.
• Emerging research highlights melatonin's involvement in immune regulation and cancer biology.
• Oxidative stress and immune suppression in the tumor microenvironment are critical drivers of cancer progression.

Purpose of the Study:

• To review melatonin's antioxidant and immunoregulatory mechanisms.
• To highlight melatonin's impact on the tumor immune microenvironment.
• To emphasize the role of macrophages in melatonin's anticancer effects.

Main Methods:

• Literature review of studies on melatonin's effects on oxidative stress and immune cells.
• Analysis of melatonin's influence on macrophage polarization (M1 vs. M2 phenotypes).
• Examination of melatonin's impact on chronic inflammation and mitochondrial function within the tumor context.

Main Results:

• Melatonin directly scavenges reactive oxygen and nitrogen species and upregulates antioxidant enzymes.
• Melatonin modulates both innate and adaptive immune responses.
• Melatonin influences macrophage polarization towards antitumor M1 phenotypes, reduces inflammation, and improves mitochondrial function.

Conclusions:

• Melatonin possesses significant antioxidant and immunomodulatory properties relevant to cancer.
• Macrophages are a pivotal target for melatonin's anticancer effects within the tumor microenvironment.
• Targeting macrophage polarization with melatonin represents a promising therapeutic strategy for cancer treatment.