Effect of Testin Gene on Radiosensitivity of Nasopharyngeal Cancer 5-8F Cells / 肿瘤防治研究

Objective To investigate the effect of TES gene on the radiosensitivity of nasopharyngeal carcinoma 5-8F cells. Methods Specimens of 5-8F cells (unprocessed group) and 5-8F cells with high TES expression (TES group) were irradiated at 0, 2, 4, 6, and 8 Gy radiation dose points.Cell clone formation experiment was conducted to draw the survival curve.Twenty-four BALB/c nude mice were randomly divided into four groups: nontransfection group, TES group, irradiation group, and TES irradiation group.A nude mouse model of nasopharyngeal carcinoma 5-8F cells was established.The length and diameter of the transplanted tumor were measured every three days, the tumor volume was calculated, and the growth curve of the transplanted tumor was drawn.After the mice were killed one month later, the tumor block was taken and weighed.The apoptosis of the transplanted tumor cells in each group was detected by flow cytometry. Results Compared with that in the unprocessed group, the survival rate of cells in the TES group was significantly lower (P < 0.01).The tumor growth rate and tumor mass of all four groups decreased in turn, while the apoptosis rate increased in turn.The TES irradiation group had the slowest tumor growth rate, greatest decrease in tumor weight, and highest apoptosis rate among the four groups.Multiple comparison revealed statistically significant differences between the groups (P < 0.05). Conclusion The testin gene can effectively improve the radiosensitivity of nasopharyngeal carcinoma 5-8F cells cultured in vitro.

[Role of Testin in nasopharyngeal squamous cancer with high ability of metastasis].

Objective:To explore the influence and regulatory mechanism of TES gene on proliferation and migration of nasopharyngeal squamous cancer(NSPC) 5-8F cell.Method:DNA fragment encoding TES was obtained by RT-PCR method from the human highly metastatic nasopharyngeal squamous carcinoma cell line 5-8F. we identified the recombinant plasmid pEGFP-N1-TES by RT-PCR and DAN sequencing. we stablely transfected the pEGFP-N1-TES into the human highly metastatic nasopharyngeal squamous carcinoma cell line 5-8F, and detected the expression of TES by the RT-PCR and Western-blot method. And detected the impact of 5-8F cells transfection by flow cytometry and scratch tests.Result:Flow cytometry analysis showed that the apoptotic in 5-8F/pEGFP- N1-TES was significantly higher than non-transected TES and 5-8F/pEGFP-N1,and the differences were statistically significant(P<0.05).Cell scratch experiments showed that the 5-8F/pEGFP-N1-TES group cell migration rate was obviously lower than nontransected TES and 5-8F/pEGFP-N1 group in the first 12 h, 24 h and 48 h.The difference was significant(P<0.01).Conclusion:The stable transfectant cell model was established successfully. TES in vitro could significantly increase apoptosis and reduce the athletic ability. And thus TES gene might be a novel candidate of tumor-suppressor.

TES inhibits colorectal cancer progression through activation of p38.

The human TESTIN (TES) gene has been identified as a candidate tumor suppressor based on its location at a common fragile site - a region where loss of heterozygosity has been detected in numerous types of tumors. To investigate its role in colorectal cancer (CRC), we examined TES protein levels in CRC tissue samples and cell lines. We observed that TES was markedly reduced in both CRC tissue and cell lines. Additionally, overexpression of TES significantly inhibited cell proliferation, migration, and invasion, while increasing cell apoptosis in colon cancer cells. By contrast, shRNA-mediated TES knockdown elicited the opposite effects. TES inhibited the progression of CRC by up-regulating pro-apoptotic proteins, down-regulating anti-apoptotic proteins, and simultaneously activating p38 mitogen-activated protein kinase (MAPK) signaling pathways. Collectively, these data indicate that TES functions as a necessary suppressor of CRC progression by activating p38-MAPK signaling pathways. This suggests that TES may have a potential application in CRC diagnosis and targeted gene therapy.

[Expression and clinical significance of Testin in nasopharyngeal carcinoma].

Objective:Our purpose was to investigate the expression of Testin gene,and its possible relationship with the clinicopathological features of human nasopharyngeal carcinoma.Method:The expression of Testin in nasopharyngeal carcinoma tissues were detected by immunohistochemistry methods,semi-quantitative reverse transcriptase polymerase chain reaction and Western blot.The correlations of Testin to clinicopathologic features of nasopharyngeal carcinoma were analyzed.Result:The mRNA level of Testin was down-regulated in human nasopharyngeal carcinoma.The positive rate of Testin protein was significantly lower in human nasopharyngeal carcinoma tissues than that in nomal tissues;The protein level of Testin was down-regulated in cancers as compared with corresponding normal tissues.Testin expression was positively correlated with the differentiation of nasopharyngeal carcinoma.Meanwhile,differences in gender and age were not significance(P>0.05 respectively) .There was a significant correlation between invasion,distant metastasis and differentiation degree and Testin expression(P<0.05 respectively).Conclusion:The decreased expression of Testin gene may play an importmant role in the development of esophageal squamous cancer.Thus Testin gene might be a novel candidate of tumor-suppressor.It may be an objective marker for prognostic factor and malignant level for nasopharyngeal carcinoma.