The Emerging Role of Exosomes in Oral Squamous Cell Carcinoma

Abstract

Oral cancer constitutes approximately 2% of all cancers, while the most common type, oral squamous cell carcinoma (OSCC) represents 90% of oral cancers. Although the treatment of OSCC has improved recently, it still has a high rate of local recurrence and poor prognosis, with a 5-year survival rate of only 50%. Advanced stage OSCC tends to metastasize to lymph nodes. Thus, exploring new therapeutic strategies for OSCC is therefore an urgent priority. Exosomes, the small membrane vesicles derived from endosomes, have been detected in a wide array of bodily fluids. Exosomes contain a diversity of proteins, mRNAs, and non-coding RNAs, including microRNAs, long non-coding RNAs, piRNAs, circular RNAs, tsRNAs, and ribosomal RNAs, which are delivered to neighboring cells or even transported to distant sites. Exosomes have been associated with the tumorigenesis of OSCC, promote the proliferation, colonization, and metastasis of OSCC by transferring their contents to the target cells. Furthermore, exosomes are involved in the regulation of the tumor microenvironment to transform conditions favoring cancer progression in vivo. In this review, we summarize the crucial role of exosomes in the tumorigenesis and progression of OSCC and discuss the potential clinical application of exosomes in OSCC treatment.

Epidermal growth factor/epidermal growth factor receptor signaling blockage inhibits tumor cell‐derived exosome uptake by oral squamous cell carcinoma through macropinocytosis

“…Exosomes, which are small membrane vesicles released by various cells, including tumor cells, can be taken up by parent and recipient cells, consequently affecting their function and activity through included materials, such as lipids, proteins, and nucleic acids from their cell of origin 5 . Studies have shown that tumor‐derived exosomes affect tumorigenesis, tumor progression, and metastasis by exhibiting immunosuppressive properties, facilitating tumor invasion and metastasis, stimulating tumor cell proliferation, or inducing drug resistance 6,7 . We also previously demonstrated that OSCC cell‐derived exosomes taken up by OSCC cells themselves significantly promoted proliferation, migration, invasion, and growth of tumor xenografts implanted into nude mice through the activation of the phosphatidylinositol 3‐kinase (PI3K)/Akt, MAPK/extracellular signal regulated kinase (ERK), JNK‐1/2 pathways 8 .…”

Latest Trend of Milk Derived Exosomes: Cargos, Functions, and Applications

“…To the contrary of most reported findings, Melnik and Schmitz (73) pointed out that continuous intake of milk exosomes may pose a risk for chronic diseases including obesity, type 2 diabetes mellitus, osteoporosis, Parkinson's disease, and common cancers, mainly due to the miRNAs inside the exosomes: such as miR-148a which suppress inhibitor of adipogenesis, miR-29b which belongs the diabetogenic miR family, miR-155 which can promote the initiation and progression of Parkinson's disease in humans, and miR-21which promotes tumor progression. The miRNA-21, which was observed in milk exosomes, can enhance mTOC1driven metabolic processes by attenuating the inhibitory effects of various tumor suppressor proteins on mTORC1-signaling (85,86). The authors mentioned that as human breast milk is the ideal food for infant, persistent high cow milk signaling during adolescence and adulthood may promote diseases of civilization.…”

lncRNA TSPEAR-AS2, a Novel Prognostic Biomarker, Promotes Oral Squamous Cell Carcinoma Progression by Upregulating PPM1A via Sponging miR-487a-3p

“…Despite the fact that great advances have been made in surgical techniques and chemoradiation therapy, the 5-year survival rate for OSCC patients remains very low [4,5]. The inability for diagnosing in the preliminary phase refers to the main reason for the unfavorable outcome of OSCC cases [6,7]. It has been confirmed the involvements of multiple genetic and epigenetic abnormality in OSCC progressions, but the molecular mechanisms involved in OSCC tumorigenesis remain largely unclear.…”