RelA-Mediated BECN1 Expression Is Required for Reactive Oxygen Species-Induced Autophagy in Oral Cancer Cells Exposed to Low-Power Laser Irradiation.

Low-power laser irradiation (LPLI) is a non-invasive and safe method for cancer treatment that alters a variety of physiological processes in the cells. Autophagy can play either a cytoprotective role or a detrimental role in cancer cells exposed to stress. The detailed mechanisms of autophagy and its role on cytotoxicity in oral cancer cells exposed to LPLI remain unclear. In this study, we showed that LPLI at 810 nm with energy density 60 J/cm2 increased the number of microtubule associated protein 1 light chain 3 (MAP1LC3) puncta and increased autophagic flux in oral cancer cells. Moreover, reactive oxygen species (ROS) production was induced, which increased RelA transcriptional activity and beclin 1 (BECN1) expression in oral cancer cells irradiated with LPLI. Furthermore, ROS scavenger or knockdown of RelA diminished LPLI-induced BECN1 expression and MAP1LC3-II conversion. In addition, pharmacological and genetic ablation of autophagy significantly enhanced the effects of LPLI-induced apoptosis in oral cancer cells. These results suggest that autophagy may be a resistant mechanism for LPLI-induced apoptosis in oral cancer cells.

Warm and neutral tumescent anesthetic solutions are essential factors for a less painful injection.

BACKGROUND: Tumescent local anesthesia is widely used in dermatologic surgery. Minimizing pain associated with injections is crucial to successful surgical procedures. OBJECTIVE: This study investigates the pain associated with warm and room temperatures in neutralized or nonneutralized tumescent anesthetic solutions injection. METHODS: Thirty-six patients with axilla osmidrosis who underwent local anesthesia for surgery were randomly assigned to three groups. Group A received warm neutral (40 degrees C) and room-temperature neutral (22 degrees C) tumescent injections to each axillary region. Group B received warm neutral (pH 7.35) and warm nonneutral (pH 4.78) tumescent injections on each side of axilla. Group C received warm nonneutral and room-temperature nonneutral tumescent injections on each side of axilla. Pain associated with infiltration of anesthesia was rated on a visual analog scale (VAS). RESULTS: A statistically significant decrease (p < .001) in pain sensation was reported on the warm, neutral injection side (mean rating, 32.7 mm) compared with the room-temperature, neutral injection side (mean rating, 53.3 mm). Patient-reported pain intensity was significantly lower on the side that received warm, neutral tumescent anesthesia (mean rating, 26.8 mm) than on the side receiving warm, nonneutral tumescent anesthesia (mean rating, 44.9 mm; p < .001). The difference in VAS scores between warm neutral (mean rating, 23.9 mm) and room-temperature nonneutral (mean rating, 61.2 mm) was statistically significant (p < .001). CONCLUSION: The warm, neutral tumescent anesthetic preparation effectively suppressed patient pain during dermatologic surgical procedures.