Research On The Mechanism Of LncRNA TUSC7 Mediated Apoptosis In Osteosarcoma

Objective:To explore whether Lnc RNA TUSC7 plays an important role in the proliferation,migration and invasion of osteosarcoma(OS)and the possible mechanism that affects the development of OS.And to study the role of Lnc RNA TUSC7 in OS in nude mice.Methods:(1)qRT-PCR technique was used to detect the expression of TUSC7 in OS and normal bone tissues.The difference of TUSC7 expression between human OS cell lines and osteoblast cell line was detected.(2)TUSC7 overexpression vector or control vector was used to transfect U2 OS cells and MG63 cells respectively.The expression of TUSC7 was detected by q RT-PCR technique,and the proliferation rate of U2 OS and MG63 cells after overexpression of TUSC7 was detected by CCK-8 and colony formation assay.(3)Transwell assay was used to detect the migration and invasion of U2 OS and MG63 cells after overexpression of TUSC7.(4)The changes of early and late apoptosis rates in TUSC7 transfection group were analyzed by apoptosis detection experiment.(5)The results of Western blotting assay showed that the protein expression of anti-apoptosis protein Bcl2 was significantly decreased,while the protein expression levels of pro-apoptosis proteins Bax,Caspase-3 and Caspase-8 were significantly increased.(6)TUSC7 overexpression vector and control vector were injected into the subcutaneous tissue of the back of nude mice in TUSC7 group and Vector group respectively,and the changes of tumor volume,weight and body weight of mice were measured regularly.The number of proliferative cells in TUSC7 group and Vector group was observed by HE and Ki-67 staining.To explore the effect of TUCS7 on the growth of osteosarcoma in nude mice.Results:(1)qRT-PCR results showed that the expression of TUSC7 in OS was significantly lower than that in normal bone tissue.Compared with human osteoblast cell line,the expression of TUSC7 in human OS cell line was significantly decreased,especially in U2 OS and MG63 cells.(2)q RT-PCR results showed that the expression of TUSC7 increased significantly after TUSC7 transfection into U2 OS cells and MG63 cells.The results of CCK-8and colony formation experiments showed that the cell proliferation rate and colony formation ability decreased significantly after overexpression of TUSC7.(3)The results of Transwell assay showed that the migration and invasion of U2 OS and MG63 cells decreased significantly after overexpression of TUSC7.(4)The results of apoptosis detection showed that the apoptosis rate in TUSC7 group was significantly higher than that in Vector group.(5)The results of Western blotting assay showed that the protein expression of anti-apoptosis protein Bcl2 was significantly decreased,while the protein expression levels of pro-apoptosis proteins Bax,Caspase-3 and Caspase-8 were significantly increased.(6)The results of in vivo experiment showed that the growth of OS in TUSC7 group was significantly lower than that in Vector group,but there was no significant difference in body weight between the two groups.HE and Ki-67 staining showed that the number of proliferative cells decreased in TUSC7 group.Conclusion:(1)The expression of Lnc RNA TUSC7 is decreased in OS,and its overexpression can inhibit the progression of OS.(2)Lnc RNA TUSC7 can inhibit the progression of OS by mediating apoptosis.(3)Overexpression of Lnc RNA TUSC7 can inhibit the growth of OS in nude mice.