Modifiable risk factors for oral cavity cancer in non-smokers: A systematic review and meta-analysis.

BACKGROUND: Oral cavity cancer (OCC) is traditionally associated with smoking, but there is an increasing prevalence of the disease among non-smokers. This review investigates possible modifiable risk factors in the development of OCC in non-smokers (OCCNS). METHODS: PubMed, EMBASE, Web of Science, and Scopus were searched for publications prior to June 2021. Comparative studies investigating modifiable OCCNS risk factors were identified following PRISMA guidelines. Publication date, population size, and results were indexed. Study quality was assessed using MINORS (Methodological Index for Non-Randomized Studies). Factors examined by multiple studies were analyzed using random-effect meta-analysis framework. RESULTS: Literature search resulted in 1,625 unique publications. 52 records met inclusion criterion, investigating alcohol (n = 22), chewing products (n = 18), diet (n = 7), dental health (n = 11), and medical comorbidities (n = 6). CONCLUSION: This review demonstrates the paucity of large studies investigating OCCNS risk factors. Further investigation is warranted to help clinicians risk-stratify patients without traditional risk factors.

Transfacial transmandibular approach to the masticator space: Excision of odontogenic myxoma arising from the mandibular condyle.

Odontogenic myxomas are an uncommon benign odontogenic tumor that can present with a wide variety of symptomatology depending on location and potentially be locally destructive. The present case describes a 66-year-old female who presented with left lower facial paresthesia, left aural fullness and hearing loss. She was found to have an odontogenic myxoma that involved the condylar head and extended into the masticator space. In this report we detail our surgical approach utilizing a preauricular transfacial transmandibular approach to the masticator space. In addition, we will discuss various approaches to the masticator space and infratemporal fossa along with considerations on how to manage facial nerve paralysis, facial contour deformities, and post-operative rehabilitation for permanent unilateral condylar head disarticulation.

Cigarette smoke exposure reveals a novel role for the MEK/ERK1/2 MAPK pathway in regulation of CFTR.

BACKGROUND: Cystic fibrosis transmembrane conductance regulator plays a key role in maintenance of lung fluid homeostasis. Cigarette smoke decreases CFTR expression in the lung but neither the mechanisms leading to CFTR loss, nor potential ways to prevent its loss have been identified to date. METHODS: The molecular mechanisms leading to down-regulation of CFTR by cigarette smoke were determined using pharmacologic inhibitors and silencing ribonucleic acids (RNAs). RESULTS: Using human bronchial epithelial cells, here we show that cigarette smoke induces degradation of CFTR that is attenuated by lysosomal inhibitors, but not proteasome inhibitors. Cigarette smoke can activate multiple signaling pathways in airway epithelial cells, including the MEK/Erk1/2 MAPK (MEK: mitogen-activated protein kinase/ERK kinase Erk1/2: extracellular signal-regulated kinase 1/2 MAPK: Mitogen-activated protein kinase) pathway regulating cell survival. Interestingly, pharmacological inhibition of the MEK/Erk1/2 MAPK pathway prevented the loss of plasma membrane CFTR upon cigarette smoke exposure. Similarly, decreased expression of Erk1/2 using silencing RNAs prevented the suppression of CFTR protein by cigarette smoke. Conversely, specific inhibitors of the c-Jun N-terminal kinase (JNK) or p38 MAPK pathways had no effect on CFTR decrease after cigarette smoke exposure. In addition, inhibition of the MEK/Erk1/2 MAPK pathway prevented the reduction of the airway surface liquid observed upon cigarette smoke exposure of primary human airway epithelial cells. Finally, addition of the antioxidant N-acetylcysteine inhibited activation of Erk1/2 by cigarette smoke and precluded the cigarette smoke-induced decrease of CFTR. CONCLUSIONS: These results show that the MEK/Erk1/2 MAPK pathway regulates plasma membrane CFTR in human airway cells. GENERAL SIGNIFICANCE: The MEK/Erk1/2 MAPK pathway should be considered as a target for strategies to maintain/restore CFTR expression in the lung of smokers.