Effects of methylene blue photodynamic therapy on oral carcinoma and leukoplakia cells

Abstract

Objective Methylene blue (MB) is a readily available and affordable substrate that can be used as a photosensitizer for photodynamic therapy (PDT). The objective of this study was to determine if PDT with MB can downregulate matrix metalloproteinases (MMPs) related to oral carcinoma. Methods Cell cultures of oral squamous cell carcinoma (CA‐9‐22), oral leukoplakia (MSK‐Leuk1), and immortalized keratinocytes (Rhek‐1A) were photosensitized with MB and treated with PDT. MMP‐9 gene expression was interrogated via qRT‐PCR. The 3‐(4,5‐dimethyl‐2‐thiazolyl)‐2,5‐diphenyl‐2H‐tetrazolium bromide (MTT) assay was used to confirm the efficacy of MB PDT. Results MMP‐9 gene expression was found to be significantly decreased in oral carcinoma, leukoplakia, and immortalized keratinocytes with use of MB PDT. Conclusion This work demonstrates that MB‐mediated PDT can downregulate MMPs which are critical to the invasion and metastasis of oral cancer. These results suggest that MB PDT could be a clinically significant and cost‐effective treatment for oral leukoplakia and carcinoma. Level of Evidence NA

Photodynamic Therapy with an Association of Methylene Blue and Toluidine Blue Promoted a Synergic Effect against Oral Squamous Cell Carcinoma

“…However, MB-PDT effects on OSCCs are poorly described and also evaluated with methodologies less sensitive than the ATP-based assay as was used in the present work [37][38][39]. Previously, KOFLER and colleagues [37] demonstrated cytotoxic activity of MB alone or with PDT in CA-9-22 cells, and LE and colleagues [38] showed the cytotoxic activity of MB in SCC-25 cells. Values represent the mean ± SD and were calculated from three independent experiments.…”

“…MB-PDT is well employed against several types of cancer such as: cervical carcinoma, leukemia, osteosarcoma, mammary adenocarcinoma, melanoma and lung adenocarcinoma [7,29,[34][35][36]. However, MB-PDT effects on OSCCs are poorly described and also evaluated with methodologies less sensitive than the ATP-based assay as was used in the present work [37][38][39]. Previously, KOFLER and colleagues [37] demonstrated cytotoxic activity of MB alone or with PDT in CA-9-22 cells, and LE and colleagues [38] showed the cytotoxic activity of MB in SCC-25 cells.…”

In Vitro Exploration of Dark Cytotoxicity of Anthocyanin-Curcumin Combination, A Herbal Photosensitizer

“…Photodynamic therapy (PDT) is an upcoming new therapeutic strategy employed in a wide variety of oral lesions and oral malignancies [ 1 ]. Oral potentially malignant disorders are precursors of oral malignancies as it is associated with the use of tobacco [ 2 ].…”