Advances in the Biological Functions of Extracellular Vesicles and their Potential Use in Treating Oral Cancer.

Extracellular vesicles (EVs) are membranous spheroid organelles secreted by various cells during their development. Previous studies have proved that the elimination of metabolic waste products from the cells is one of the key biological functions of EVs. Besides, recent studies suggest that EVs also promote intercellular information transmission thus further regulating the external environment of cells, especially during the development of cancer. Different EVs are produced by tumor cells and tumor-related cells during the development of tumors. Based on their sources and contents, different EVs may promote the proliferation of tumor cells, interfere with the function of immune cells, or destroy normal tissue barriers. As a landmark component in the occurrence and development of tumors, EVs can be used to solve the biological behaviors that hinder tumor treatment, such as drug resistance and immune escape. Oral cancer is a highly prevalent cancer type in clinic and current therapies often fail to effectively inhibit its deterioration. Based on their essential roles in cancer development, EVs therefore possess great potential to be a target for oral cancer treatment. In this review, we focused on the origin and classification of vesicles in oral cancer tissues around the tumor microenvironment, described their biological functions, and discussed their potential for cancer treatment in combination with existing research methods. In addition, we highlighted the current challenges and recommendations of EVs for the treatment of oral cancer in clinic.

Onlays/partial crowns versus full crowns in restoring posterior teeth: a systematic review and meta-analysis.

BACKGROUND: Tooth-colored onlays and partial crowns for posterior teeth have been used increasingly in clinics. However, whether onlays/partial crowns could perform as well as full crowns in the posterior region was still not evaluated thoroughly. METHODS: A literature search was conducted without language restrictions in Pubmed, Embase, Cochrane Central Register of Controlled Trial and Web of science until September 2021. RCTs, prospective and retrospective observational studies with a mean follow-up of 1 year were selected. Cochrane Collaboration's tool was adopted for quality assessment of the RCT. The quality of observational studies was evaluated following Newcastle-Ottawa scale. The random-effects and fixed-effects model were employed for meta-analysis. RESULTS: Four thousand two hundred fifty-seven articles were initially searched. Finally, one RCT was identified for quality assessment and five observational studies for qualitative synthesis and meta-analysis. The RCT was of unclear risk of bias while five observational studies were evaluated as low risk. The meta-analysis indicated no statistically significant difference in the survival between onlays/partial crowns and full crowns after 1 year (OR = 0.55, 95% CI: 0.02-18.08; I2 = 57.0%; P = 0.127) and 3 years (OR = 0.65, 95% CI: 0.20-2.17; I2 = 0.0%; P = 0.747). For the success, onlays/partial crowns performed as well as crowns (OR = 0.58, 95% CI: 0.20-1.72; I2 = 0.0%; P = 0.881) at 3 years. No significant difference of crown fracture existed between the two methods (RD = 0.00, 95% CI: - 0.03-0.03; I2 = 0.0%; P = 0.972). CONCLUSIONS: Tooth-colored onlays/partial crowns performed as excellently as full crowns in posterior region in a short-term period. The conclusions should be further consolidated by RCTs with long-term follow-up.

Photobiomodulation Therapy/Photodynamic Therapy Versus Steroid Therapy for Oral Lichen Planus: A Systematic Review and Meta-Analysis.

Objective: To evaluate the efficiency of photobiomodulation therapy (PBMT) or photodynamic therapy (PDT) in treating oral lichen planus (OLP) as well as identifiy the side effects when compared with steroid therapy. Background: Nowadays, PBMT and PDT are increasingly applied for treating OLP with minimal adverse effects. Methods: The electronic databases of PubMed, Cochrane Central Register of Controlled Trial, Web of Science, and Embase were searched until March 13, 2020. Randomized controlled trials (RCTs) with 1 month of follow-up period were selected. Two reviewers extracted data from selected studies independently. Cochrane collaboration's tool for assessing risk of bias was used for assessing the quality of the RCTs. The random-effects model was employed for meta-analysis. Results: One thousand fifteen studies were initially identified. Finally, nine RCTs were included for quality assessment and seven studies for meta-analysis. Four RCTs were of unclear risk of bias and five were assessed as high risk of bias. The comparison showed no significant differences for pain scores [visual analog scale (VAS)] [mean differences (MD) = 0.38, confidence interval (CI) = 95% -0.64 to 1.40] and severity scores (reticular-atrophic-erosive scores) (MD = 1.67, CI = 95% -1.13 to 4.46) between topical corticosteroid therapy and PBMT after 1 month. For PDT, no significant differences were observed for sign scores (Thongprasm sign scoring) (MD = -0.31, CI = 95% -1.52 to 0.91) and pain scores (VAS) (MD = -2.30, CI = 95% -5.88 to 1.28) of the lesions when compared with topical corticosteroid therapy after 1 month of follow-up period. One study reported the discomfort of the affected area in patients of the PDT group when probe tip was moved. Conclusions: PBMT and PDT could be reliable alternatives to topical corticosteroids for OLP with no or less severe complications in a short-term period. However, further well-designed RCTs with long-term period are recommended to consolidate the conclusions in this regard.

The role of long non-coding RNA ANRIL in the carcinogenesis of oral cancer by targeting miR-125a.

Recently, increasing evidence has indicated that lncRNAs may play a critical role in the progression of oral cancer (OC). However, whether lncRNA-ANRIL is involved in the tumorigenesis of OC remains undetermined. In the present study, ANRIL showed significantly higher, while miR-125a showed lower, expression in OC tissues and sera than in normal controls. MTT, colony formation, flow cytometry analysis, wound-healing, transwell and mice xenograft model assays were used to detect the proliferation, migration, and invasion of ARNIL-overexpressing HB56 cells and ARNIL-knockdown CAL27 cells. The results showed that cell proliferation, migration, and invasion were significantly increased by ARNIL overexpression and decreased by ARNIL silencing in oral cancer cells. Furthermore, we found a negative correlation between ARNIL and miR-125a, and ARNIL acts as a miRNA-sponge by directly interacting with miR-125a.