Red Light Phototherapy Using Light-Emitting Diodes Inhibits Melanoma Proliferation and Alters Tumor Microenvironments
Evan Austin1,2, Alisen Huang1, Jennifer Y Wang1
1Department of Dermatology, State University of New York (SUNY) Downstate Medical Center, Brooklyn, NY, United States.
Background:
Total annual cancer rates have decreased due to improved treatment and prevention. However, the incidence of melanoma is rising, and not all patients respond to immune and targeted approaches. Therefore, we sought to determine the efficacy of red light (RL) phototherapy in preclinical models of melanoma.
Methods:
Melanoma cells (A375, B16F10, MNT-1) were irradiated with RL. Melanoma proliferation, apoptosis, oxidative stress, and p53 phosphorylation were measured in vitro. In C57BL/6 mice, phototherapy safety, B16F10 tumor growth, and immunocyte infiltration were assessed following RL.
Results:
In vitro, 640 J/cm2 RL decreased cellular proliferation without increasing apoptosis, while 1280 J/cm2 increased apoptosis. RL increased intracellular reactive oxygen species generation and p53 phosphorylation. In animal models, 2560 J/cm2 RL significantly prevented melanoma growth and increased the expression of CD103+ dendritic cells. 1280 and 1920 J/cm2 RL decreased tumor volume, but not significantly. RL did not cause skin inflammation or erythema in normal skin.
Conclusion:
RL represents a potentially safe and effective melanoma therapeutic. RL prevented tumor growth and increased the expression of immune markers, such as CD103, that are associated with favorable melanoma outcomes. Further research is needed to determine the optimal clinical treatment regimen for melanoma using RL.
Insights
Red light (RL) phototherapy shows promise for melanoma treatment. This study found RL inhibited melanoma growth and boosted immune cell markers in preclinical models, suggesting a potential new therapeutic approach.
Area of Science:
- Oncology
- Photomedicine
- Immunology
Background:
- Melanoma incidence is increasing despite advances in cancer treatment.
- Current therapies, including immune and targeted approaches, are not effective for all melanoma patients.
- Investigating novel therapeutic strategies for melanoma is crucial.
Purpose of the Study:
- To evaluate the efficacy of red light (RL) phototherapy as a potential treatment for melanoma.
- To assess the effects of RL on melanoma cell proliferation, apoptosis, and oxidative stress.
- To determine the safety and impact of RL on tumor growth and immune response in preclinical melanoma models.
Main Methods:
- Melanoma cell lines (A375, B16F10, MNT-1) were exposed to varying doses of RL.
- In vitro assessments included cell proliferation, apoptosis, oxidative stress, and p53 phosphorylation.
- In vivo studies in mice evaluated RL safety, B16F10 tumor growth, and immunocyte infiltration.
Main Results:
- RL at 640 J/cm² reduced melanoma proliferation; higher doses (1280 J/cm²) induced apoptosis.
- RL increased reactive oxygen species and p53 phosphorylation in melanoma cells.
- In vivo, RL (2560 J/cm²) significantly inhibited tumor growth and increased CD103+ dendritic cells, with no observed skin inflammation.
Conclusions:
- Red light phototherapy demonstrates potential as a safe and effective treatment for melanoma.
- RL therapy can inhibit melanoma tumor growth and enhance immune markers like CD103, associated with better patient outcomes.
- Further clinical research is warranted to establish optimal RL treatment protocols for melanoma.
