RESUMO
Objective:To investigate the effect of BMAL1 gene on the proliferation, migration and invasion ability of radiation-resistant nasopharyngeal carcinoma cell line (5-8FR) and the molecular mechanism. Methods:A multi-target click model was constructed for radiation-resistant nasopharyngeal carcinoma cell line 5-8FR by low-dose fractionated irradiation, and the results of clone formation assay were used to fit the multi-target click model and calculate the sensitization ratio of radiotherapy. The expression levels of PI3K/Akt/MMP-2/9 signaling pathway-related proteins in 5-8FR and control 5-8F cell lines were detected by Western blot. The overexpression and knockdown vectors of BMAL1 gene were constructed and transfected with 5-8F and 5-8F cell lines, respectively. The BMAL1 gene overexpression (pcDNA-BMAL1) and its control (pcDNA) and interference (BMAL1-shRNA) and control (con-shRNA) cell lines were stably transfected with nasopharyngeal carcinoma cell line 5-8F and radiation-resistant cell line 5-8FR, respectively. Western blot was performed to verify the infection efficiency and detect the changes of PI3K/Akt/MMP-2/9 signaling pathway-related proteins after overexpression or interference of BMAL1 gene in both groups of cells. CCK-8 assay, cell scratch test and Transwell chamber test were conducted to investigate the proliferation, migration and invasion capabilities of 5-8FR cell line after overexpression or interference of BMAL1 gene. Results:BMAL1 gene expression was down-regulated, and those of PI3K/Akt pathway proteins and downstream related molecules of MMP-2 and MMP-9 were up-regulated, and TIMP-2 and TIMP-1 expression was down-regulated in nasopharyngeal carcinoma radiation-resistant cell lines. Overexpression of BMAL1 gene inhibited the expression of PI3K/Akt pathway proteins and downstream related molecules of MMP-2 and MMP-9, promoted the expression of TIMP-2 and TIMP-1, and inhibited the proliferation, migration and invasion capabilities of radiation-resistant nasopharyngeal carcinoma cells, while interference with BMAL1 gene yielded the opposite results. Conclusions:BMAL1 gene can reverse the expression of PI3K/Akt/MMP-2/9 signaling pathway-related proteins in radiation-resistant nasopharyngeal carcinoma cell lines and inhibit the proliferation, migration and invasion capabilities of radiation-resistant nasopharyngeal carcinoma cell lines.
RESUMO
OBJECTIVE：To study the improvement effects of isopimpinelline on p-chlorophenylalanine（PCPA）-induced pineal injury model rats and its effect on expression of biological clock gene. METHODS ：Totally 60 rats were divided into blank control group（2％ polysorbate solution），model control group （2％ polysorbate solution），positive control group （melatonin，10 mg/kg） and isopimpinelline high-dose ，medium-dose and low-dose groups （3，1.5，0.75 mg/kg）. Except for blank control group ，rats in other groups were given PCPA intraperitoneally （450 mg/kg）to establish pineal injury model. After modeling finished ，they were given relevant medicine intragastrically ，once a day ，for consecutive 7 d. On the 6th day of administration ，the sleep latency and sleep duration of rats in each group were investigated by pentobarbital sodium coordination sleep test ；after last administration ， ELISA assay was used to determine the serum level of melatonin in rats. Fluorescence microscope and electron microscope were used to observe the pathological tissue and cell ultrastructure changes of the pineal gland. RT-qPCR was used to detect the mRNA expressions of biological clock gene Clock，Bmal1，Per1，Per2，Per3，Cry1，Cry2 in pineal gland of rats. RESULTS ：Compared with blank control group ，model control group had significantly longer sleep latency （P＜0.05）；serum melatonin ，mRNA expressions of Bmal1 and Per1 in pineal gland were significantly decreased （P＜0.05 or P＜0.01）while mRNA expression of Per3 was increased significantly （P＜0.05）. The pineal gland cell arrangement disorder ，nuclear pyknosis ，vacuolar degeneration increased and cell number decreased significantly ；mitochondria swollen ，cristae broken and pyknosis were observed. Compared with model control group ，the sleep latency of isopimpinelline high-dose group was shortened significantly （P＜0.05），sleep duration time was prolonged significantly （P＜0.05）；the levels of melatonin in serum ，mRNA expressions of Clock，Bmal1， Per1，Cry1 and Cry2 in pineal gland of rats were increased significantly （P＜0.05 or P＜0.01）. In isopimpinelline medium-dose group，the sleep latency was shortened significantly （P＜0.05）；the levels of melatonin in serum and mRNA expressions of Clock， Bmal1，Per1，Cry1，Cry2 in pineal gland were increased significantly （P＜0.05 or P＜0.01），while mRNA expression of Per3 was decreased significantly （P＜0.05）. In isopimpinelline low-dose group ，the levels of mRNA expressions of Clock，Bmal1，Per2 and Cry2 were increased significantly （P＜0.05），while mRNA expression of Per3 was decreased significantly （P＜0.05）. Cell arrangement disorder was improved and nuclear pyknosis vacuole degeneration was decreased to some extent in isopimpinelline groups；mitochondria swelled ，cristae fractured ，and pyknosis decreased to some extent. CONCLUSIONS ：Isopimpinelline can improve PCPA-induced pineal gland injury in rats ；it can up-regulate the expressions of positive regulators Clock，Bmal1 and negative regulators Per1，Per2，Cry1，Cry2，while down-regulate the expression of negative regulator Per3.