Sento Shinya, Sasabe Eri, Yamamoto Tetsuya
Department of Oral and Maxillofacial Surgery, Kochi Medical School, Kochi University, Kohasu, Oko-cho, Nankoku-city, Kochi 783-8505, Japan.
PLoS One. 2016 Feb 5;11(2):e0148454. doi: 10.1371/journal.pone.0148454. eCollection 2016.
Exosomes are 30-100 nm-sized membranous vesicles, secreted from a variety of cell types into their surrounding extracellular space. Various exosome components including lipids, proteins, and nucleic acids are transferred to recipient cells and affect their function and activity. Numerous studies have showed that tumor cell-derived exosomes play important roles in tumor growth and progression. However, the effect of exosomes released from oral squamous cell carcinoma (OSCC) into the tumor microenvironment remains unclear. In the present study, we isolated exosomes from OSCC cells and investigated the influence of OSCC cell-derived exosomes on the tumor cell behavior associated with tumor development. We demonstrated that OSCC cell-derived exosomes were taken up by OSCC cells themselves and significantly promoted proliferation, migration, and invasion through the activation of the PI3K/Akt, MAPK/ERK, and JNK-1/2 pathways in vitro. These effects of OSCC cell-derived exosomes were obviously attenuated by treatment with PI3K, ERK-1/2, and JNK-1/2 pharmacological inhibitors. Furthermore, the growth rate of tumor xenografts implanted into nude mice was promoted by treatment with OSCC cell-derived exosomes. The uptake of exosomes by OSCC cells and subsequent tumor progression was abrogated in the presence of heparin. Taken together, these data suggest that OSCC cell-derived exosomes might be a novel therapeutic target and the use of heparin to inhibit the uptake of OSCC-derived exosomes by OSCC cells may be useful for treatment.
外泌体是大小为30-100纳米的膜性囊泡,由多种细胞类型分泌到其周围的细胞外空间。包括脂质、蛋白质和核酸在内的各种外泌体成分被转移到受体细胞并影响其功能和活性。大量研究表明,肿瘤细胞来源的外泌体在肿瘤生长和进展中发挥重要作用。然而,口腔鳞状细胞癌(OSCC)释放到肿瘤微环境中的外泌体的作用仍不清楚。在本研究中,我们从OSCC细胞中分离出外泌体,并研究了OSCC细胞来源的外泌体对与肿瘤发展相关的肿瘤细胞行为的影响。我们证明,OSCC细胞来源的外泌体被OSCC细胞自身摄取,并通过激活PI3K/Akt、MAPK/ERK和JNK-1/2信号通路在体外显著促进增殖、迁移和侵袭。用PI3K、ERK-1/2和JNK-1/2药理抑制剂处理可明显减弱OSCC细胞来源的外泌体的这些作用。此外,用OSCC细胞来源的外泌体处理可促进植入裸鼠的肿瘤异种移植物的生长速度。在存在肝素的情况下,OSCC细胞对外泌体 的摄取及随后的肿瘤进展被消除。综上所述,这些数据表明,OSCC细胞来源的外泌体可能是一个新的治疗靶点,使用肝素抑制OSCC细胞对OSCC来源外泌体的摄取可能对治疗有用。