Zoledronic acid impairs oral cancer stem cells by reducing CCL3

Mitochondria in oral cancer stem cells: Unraveling the potential drug targets for new and old drugs

Head and neck cancer is a major health problem worldwide, with most cases arising in the oral cavity. Oral squamous cell carcinoma (OSCC) is the most common type of oral cancer, accounting for over 90% of all cases. Compared to other types of cancer, OSCC, has the worse prognosis, with a 5-year survival rate of 50%. Additionally, OSCC is characterized by a high rate of resistance to chemotherapy treatment, which may be partly explained by the presence of cancer stem cells (CSC) subpopulation. CSC can adapt to harmful environmental condition and are highly resistant to both chemotherapy and radiotherapy treatments, thus contributing to tumor relapse. The aim of this review is to highlight the role of mitochondria in oral CSC as a potential target for oral cancer treatment. For this purpose, we reviewed some fundamental aspects of the most validated protein markers of stemness, autophagy, the mitochondrial function and energy metabolism in oral CSC. Moreover, a discussion will be made on why energy metabolism, especially oxidative phosphorylation in CSC, may offer such a diverse source of original pharmacological target for new drugs. Finally, we will describe some drugs able to disturb mitochondrial function, with emphasis on those aimed to interrupt the electron transport chain function, as novel therapeutic strategies in multidrug-resistant oral CSC. The reutilization of old drugs approved for clinical use as new antineoplastics, in cancer treatment, is also matter of revision.

Patient-derived three-dimensional culture techniques model tumor heterogeneity in head and neck cancer

Head and neck squamous cell carcinoma (HNSCC) outcomes remain stagnant, in part due to a poor understanding of HNSCC biology. The importance of tumor heterogeneity as an independent predictor of outcomes and treatment failure in HNSCC has recently come to light. With this understanding, 3D culture systems, including patient derived organoids (PDO) and organotypic culture (OTC), that capture this heterogeneity may allow for modeling and manipulation of critical subpopulations, such as p-EMT, as well as interactions between cancer cells and immune and stromal cells in the microenvironment. Here, we review work that has been done using PDO and OTC models of HNSCC, which demonstrates that these 3D culture models capture in vivo tumor heterogeneity and can be used to model tumor biology and treatment response in a way that faithfully recapitulates in vivo characteristics. As such, in vitro 3D culture models represent an important bridge between 2D monolayer culture and in vivo models such as patient derived xenografts.

Pharmacologic Interventions for Fracture Risk Reduction in the Oldest Old: What Is the Evidence?

With an increasingly older population, the proportion of patients 85 years or older seeking interventions to protect their musculoskeletal health is growing. Osteoporosis in the geriatric population presents unique diagnostic and therapeutic challenges. Multimorbidity, frailty, falls, polypharmacy, and other neurobehavioral factors influence our approach to fracture prevention in this population. The vast majority of the evidence from clinical trials establish pharmacologic fracture efficacy in postmenopausal women. The evidence is scarce for the oldest old men and women, a population also at risk for adverse events and mortality. Most studies show continued efficacy of pharmacologic interventions in this age group, although they are largely limited by small sample sizes. We herein review the available evidence of pharmacologic interventions for fracture risk reduction in this population and explore the emerging senotherapeutic interventions in the pipeline. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.