重离子束和X射线辐照对舌鳞癌细胞Tca8113中MMP-2，MMP-9表达的影响
发布时间：2018-11-24 19:22
【摘要】：放射治疗是恶性肿瘤治疗过程中重要的局部治疗手段。但常规射线在辐照过程中存在着诸多天然缺陷,其深度剂量分布呈指数衰减形式,在抵达肿瘤区域对肿瘤细胞造成杀伤的同时,对肿瘤周围组织也有一定损伤。临床上为避免辐照对正常组织的辐照损伤,通常会降低辐照总剂量。近期研究表明,常规射线在辐照剂量不足时,可导致恶性肿瘤的侵袭能力增强。所以人们便积极地寻求出一种更优越的放疗用射线——重离子束。重离子是一种高LET(Linear energy transfer)射线,其在射程末端拥有一个陡峭的高剂量Bragg峰,其可最大限度地杀伤肿瘤细胞；具有高的相对生物学效应,与常规射线相比,造成肿瘤细胞的损伤更严重。重离子束也被誉为是21世纪最为理想的放疗射线。 肿瘤向周围组织的侵袭,是肿瘤转移的最初始阶段,也是一种多因子参与的复杂过程。在这一过程中,基质金属蛋白酶(MMPs)是人体内最主要的蛋白水解酶,对癌细胞的粘附和侵袭均发挥着重要的作用。基质金属蛋白酶在许多人类的癌组织中均有表达和活性的增强,其中基质金属蛋白酶-2和基质金属蛋白酶-9(MMP-2, MMP-9)是肿瘤侵袭过程中关键因子。MMP-2和MMP-9是可以分解细胞基底膜上的Ⅳ型胶原蛋白和弹性蛋白成份,使肿瘤细胞突破基底膜的能力增强,从而促进肿瘤细胞向周围组织侵袭。 本实验以人舌鳞癌细胞株Tca8113为主要研究对象,使用不同剂量的X线和12C6+重离子束对其进行辐照,采用Western-blot法观察MMP-2和MMP-9在舌鳞癌细胞中表达的变化,反映两种辐照对于肿瘤侵袭能力的影响。结果如下： 和空白对照组相比,使用1GyX射线在辐照后12h、24h和48h, MMP-2的表达含量均有所上调(p0.05),其表达含量于24h时达到顶峰(p0.01),在48h时,MMP-2的表达有所下调；4Gy X射线辐照后的细胞中MMP-2在各个时间点的表达水平虽有所减少,但并不具备统计学差异(p0.05)。1Gy和4Gy X射线进行辐照后,细胞中MMP-9的表达也未出现明显改变(p0.05)。 1Gy重离子束对舌鳞癌细胞进行辐照后,MMP-2于12h时出现表达含量的升高(p0.05),但其表达水平与24h和48h时又出现了明显的下降(p0.05)。低剂量重离子束对舌鳞癌细胞中MMP-9的表达没有明显影响(p0.05)；在使用4Gy重离子束对肿瘤细胞进行辐照后,MMP-2和MMP-9的表达有着明显降低(p0.05)。 通过以上实验结果,可以得出：低剂量的X射线可增进舌鳞癌细胞Tca8113细胞的体外侵袭能力；高剂量的X射线对于舌鳞癌细胞Tca8113的侵袭能力并没有明显影响。低剂量的重离子束辐照对于舌鳞癌细胞Tca8113的侵袭能力没有影响；高剂量重离子束可明显抑制舌鳞癌的体外侵袭能力。和X射线相比,重离子束在抑制舌鳞癌体外侵袭方面具有更高的相对生物学效率。
[Abstract]:Radiotherapy is an important local treatment method in the treatment of malignant tumor. However, there are many natural defects in the irradiation process of conventional radiation, whose depth dose distribution is exponentially attenuated. When reaching the tumor area to kill the tumor cells, it also has some damage to the surrounding tissues of the tumor. In order to avoid radiation damage to normal tissues, the total dose of irradiation is usually reduced. Recent studies have shown that conventional radiation can enhance the invasiveness of malignant tumors when irradiation dose is insufficient. So people are actively looking for a better radiation-heavy ion beam. Heavy ions are high LET (Linear energy transfer) rays with a steep high dose Bragg peak at the end of the range, which can kill tumor cells to the maximum extent. It has high relative biological effect, and the damage of tumor cells is more serious than conventional radiation. Heavy ion beam is also regarded as the most ideal radiation in the 21 st century. Invasion of tumor to surrounding tissues is the initial stage of tumor metastasis and a complex process involving multiple factors. In this process, matrix metalloproteinase (MMPs) is the most important proteolytic enzyme in human body, and plays an important role in adhesion and invasion of cancer cells. The expression and activity of matrix metalloproteinase (MMP-2) and matrix metalloproteinase-9 (MMP-2,) are increased in many human carcinomas, including matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-2,). MMP-9) is a key factor in the process of tumor invasion. MMP-2 and MMP-9 can decompose the type 鈪，
本文编号：2354747
[Abstract]:Radiotherapy is an important local treatment method in the treatment of malignant tumor. However, there are many natural defects in the irradiation process of conventional radiation, whose depth dose distribution is exponentially attenuated. When reaching the tumor area to kill the tumor cells, it also has some damage to the surrounding tissues of the tumor. In order to avoid radiation damage to normal tissues, the total dose of irradiation is usually reduced. Recent studies have shown that conventional radiation can enhance the invasiveness of malignant tumors when irradiation dose is insufficient. So people are actively looking for a better radiation-heavy ion beam. Heavy ions are high LET (Linear energy transfer) rays with a steep high dose Bragg peak at the end of the range, which can kill tumor cells to the maximum extent. It has high relative biological effect, and the damage of tumor cells is more serious than conventional radiation. Heavy ion beam is also regarded as the most ideal radiation in the 21 st century. Invasion of tumor to surrounding tissues is the initial stage of tumor metastasis and a complex process involving multiple factors. In this process, matrix metalloproteinase (MMPs) is the most important proteolytic enzyme in human body, and plays an important role in adhesion and invasion of cancer cells. The expression and activity of matrix metalloproteinase (MMP-2) and matrix metalloproteinase-9 (MMP-2,) are increased in many human carcinomas, including matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-2,). MMP-9) is a key factor in the process of tumor invasion. MMP-2 and MMP-9 can decompose the type 鈪，
本文编号：2354747
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