Oral Cancer, miRNAs, and Cannabinoids: a complicated ménage à trois

Abstract

Oral cancer, encompassing cancers of the lips, tongue, gums, floor of the mouth, palate, and other oral structures, ranks as the 16th most common cancer globally, while oropharyngeal cancer ranks 24th. The primary risk factors for these cancers include tobacco and alcohol use. However, additional factors such as areca nut chewing, betel leaf consumption, advanced age, poor oral hygiene, wood dust exposure, chronic mechanical trauma, Candida albicans colonization, and human papillomavirus (HPV) infection have also been implicated in their etiopathogenesis. The role of cannabis consumption in oral and oropharyngeal cancer remains controversial, despite its increasing global use. Saliva, a complex biological fluid that bathes the oral cavity, offers a non-invasive, cost-effective, and safe method for obtaining a "liquid biopsy." This makes it particularly valuable for diagnosing oral disorders, including cancer. Recent studies have identified altered expression patterns of salivary microRNAs (miRNAs) in patients with oral cancer and premalignant lesions. Early detection of these changes in salivary miRNA profiles is critical for identifying premalignant lesions with the potential to progress to cancer. Furthermore, salivary miRNAs hold promise as prognostic markers for predicting patient outcomes. In this book chapter, we will explore the intricate relationship between oral cancer, cannabis consumption, and salivary miRNA expression.