Blue light irradiation suppresses oral squamous cell carcinoma through induction of endoplasmic reticulum stress and mitochondrial dysfunction

The therapeutic potential of blue light photobiomodulation in cancer treatment, particularly in inhibiting cell proliferation and promoting cell death, has attracted significant interest. Oral squamous cell carcinoma (OSCC) is a prevalent form of oral cancer, necessitating innovative treatment approaches to improve patient outcomes. In this study, we investigated the effects of 420 nm blue LED light on OSCC and explored the underlying mechanisms. Our results demonstrated that 420 nm blue light effectively reduced OSCC cell viability and migration, and induced G2/M arrest. Moreover, we observed that 420 nm blue light triggered endoplasmic reticulum (ER) stress and mitochondrial dysfunction in OSCC cells, leading to activation of the CHOP signal pathway and alterations in the levels of Bcl-2 and Bax proteins, ultimately promoting cell apoptosis. Additionally, blue light suppressed mitochondrial gene expression, likely due to its damage to mitochondrial DNA. This study highlights the distinct impact of 420 nm blue light on OSCC cells, providing valuable insights into its potential application as a clinical treatment for oral cancer.