Extracellular vesicles from oral squamous carcinoma cells display pro- and anti-angiogenic properties.

BACKGROUND: A new intercellular communication mode established by neoplastic cells and tumor microenvironment components is based on extracellular vesicles (EVs). However, the biological effects of the EVs released by tumor cells on angiogenesis are not completely understood. Here, we aimed to understand the biological effects of EVs isolated from two cell lines of oral squamous cell carcinoma (OSCC) (SCC15 and HSC3) on endothelial cell tubulogenesis. METHODS: OSCC-derived EVs were isolated with a polymer-based precipitation method, quantified using nanoparticle tracking analysis and verified for EV markers by dot blot. Functional assays were performed to assess the angiogenic potential of the OSCC-derived EVs. RESULTS: The results showed that EVs derived from both cell lines displayed typical spherical-shaped morphology and expressed the EV markers CD63 and Annexin II. Although the average particle concentration and size were quite similar, SCC15-derived EVs promoted a pronounced tubular formation associated with significant migration and apoptosis rates of the endothelial cells, whereas EVs derived from HSC3 cells inhibited significantly endothelial cell tubulogenesis and proliferation. CONCLUSION: The findings of this study reveal that EVs derived from different OSCC cell lines by a polymer-based precipitation method promote pro- or anti-angiogenic effects.

Head and neck cancer among marijuana users: a meta-analysis of matched case-control studies.

OBJECTIVES: The scientific literature presents conflicting data on a possible causal relationship between marijuana users and the development of head and neck cancer. DESIGN: This study performed a systematic review with meta-analysis. Articles were selected from various electronic databases using keywords obtained from the Medical Subject Headings (MeSH). After reading by three reviewers and scoring of methodological quality, six articles (totaling nine case-control studies) were assessed with Comprehensive Meta-Analysis(®) software. The value of effect (odds ratio) was calculated, which represented the chance of developing head and neck cancer between individuals who had smoked marijuana in their lifetime in models controlled for age, gender, race, and tobacco consumption. RESULTS: Approximately 12.6% of cases and 14.3% of controls were marijuana users. The meta-analysis found no association between exposure and disease (OR=1.021; IC 95%=0.912-1.14; p=0.718). CONCLUSION: No association between lifetime marijuana use and the development of head and neck cancer was found. The different methods of collection/presentation of results in the selected articles prevented other analyzes from being conducted. Additional studies are needed to assess for long-term effects.