Cholesterol depletion induces mesenchymal properties in oral squamous cell carcinoma cell line.

BACKGROUND: Cholesterol in cell membranes is crucial for cell signaling, adhesion, and migration. Membranes feature cholesterol-rich caveolae with caveolin proteins, playing roles in epithelial-mesenchymal transition and cancer progression. Despite elevated cholesterol levels in tumors, its precise function and the effects of its depletion in oral squamous cell carcinoma remain unclear. The aim of this study was to evaluate the influence of cholesterol depletion in oral squamous cell carcinoma cell line and epithelial-mesenchymal transition process. METHODS: Cholesterol depletion was induced on SCC-9 cells by methyl-ß-cyclodextrin and cell viability, proliferation, apoptosis, and colony formation capacities were evaluated. Gene and protein expressions were evaluated by reverse transcription polymerase chain reaction (RT-qPCR) and Western Blot, respectively, and cell sublocalization was assessed by immunofluorescence. RESULTS: Cholesterol depletion resulted in alteration of oral squamous cell carcinoma cell morphology at different concentrations of methyl-ß-cyclodextrin, as well as decreased cell proliferation and viability rates. Analysis of CAV1 transcript expression revealed increased gene expression in the treated SCC-9 during the 24 h period, at different concentrations of methyl-ß-cyclodextrin: 5 , 7.5, 10, and 15 mM, in relation to parental SCC-9. CAV1 protein expression was increased, with subsequent dose-dependent decrease. A statistically significant difference was observed in samples treated with 5 mM of methyl-ß-cyclodextrin (p = 0.02, Kruskal-Wallis test). The immunofluorescence assay showed lower cytoplasmic and membrane labeling intensity in the treated samples for CAV1. CONCLUSION: These findings indicate the modulation of cholesterol as a possible mechanism underlying the regulation of these molecules and activation of epithelial-mesenchymal transition in oral squamous cell carcinoma.

Is photobiomodulation therapy effective in reducing pain caused by toxicities related to head and neck cancer treatment? A systematic review.

Photobiomodulation therapy (PBMT) has been considered an effective method for preventing and managing certain cancer-related toxicities in head and neck cancer (HNC) patients treated with radiotherapy and chemotherapy. However, the potential effects of PBMT on pain control and analgesia resulting from these toxicities is still controversial. The aim of this systematic review was to compile available evidence of the effects of PMBT on pain control and reduced use of analgesics in HNC patients. We searched three indexed databases: MEDLINE/PubMed, Embase, and Scopus. The databases were reviewed up to and including December 2018. Only human clinical studies in English language were selected. Information was only available for mucositis and radiodermatitis. Fifteen out of 1112 studies met the inclusion criteria (14 for oral mucositis (OM) and 1 for radiodermatitis). From the 14 studies involving the prevention and treatment of OM, 10 had the study subjects compared to a placebo group. Of these 10 studies, all but 1 showed statistically significant difference related to pain control favoring the PBMT group. The study that compared PBMT with other treatment modality showed better results in pain control with PBMT. It appears that PBMT application frequency and potency impact on pain control. The only study involving the prevention and treatment of radiodermatitis was compared to placebo arm and showed statistically significant difference related to pain control favoring the PBMT group. Seven studies compared the need of analgesic medication between PBMT and placebo groups. Of these, five studies showed that the use of analgesic medication was significantly higher in the placebo group. The current evidence supports that PBMT is effective in pain control resulting from OM and radiodermatitis and may also reduce the need for analgesics. The evidence is not yet available of the effects of PBMT in other HNC treatment-related toxicities.