In Vitro Pharmaco-Toxicological Characterization of Melissa officinalis Total Extract Using Oral, Pharynx and Colorectal Carcinoma Cell Lines

Melissa officinalis is a medicinal herb with an extensive pharmacological profile that has been proven to have beneficial effects in oral and gastrointestinal disorders. However, the effects of this plant in oral, pharyngeal, and colorectal malignancies, types of cancer with an increased incidence in recent years, are less investigated. The present study aims to evaluate the pharmacological profile of a Melissa officinalis total extract for potential benefits in oral, pharynx and colorectal carcinoma. The LC-MS profile of MO total extract (MOte) indicated a rich content in polyphenols, data that support the potent antioxidant capacity exhibited and the antimicrobial activity against both Gram-negative and Gram-positive bacteria. In addition, MOte triggered a dose-dependent and selective decrease in the viability of tumor cells (tongue and pharynx squamous cell carcinomas, and colorectal adenocarcinoma), with the most significant effect being recorded at 100 μg/mL. At the same concentration, MOte exhibited an antiangiogenic effect by inhibiting the process of angiogenesis in ovo. Overall, our findings support the potential benefits of Melissa officinalis leaf total extract as a valuable candidate for the prophylaxis of oral, pharyngeal and colorectal neoplasms.