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Objective To investigate the effect and underlying mechanism of lncRNA MEG3 on the radiosensitivity of nasopharyngeal carcinoma cells.Methods this experiment,overexpression control group,MEG3 overexpression group,miR-NC inhibition group,miR-7-5p inhibition group,overexpression control+4 Gy group,MEG3 overexpression+4 Gygroup,miR-NC inhibition+4 Gy group,miR-7-5p inhibition+4 Gy group,MEG3 overexpression + miR-NC overexpression group,MEG3 overexpression + miR-7-Sp overexpression group were established.The expression of miR-7-5p and MEG3 was detected by qRT-PCR.The radiosensitivity of nasopharyngeal carcinoma cells was measured by clone formation assay.Cell apoptosis was assessed by flow cytometry.The fluorescence activity was evaluated by dual luciferase reporter assay.Results MEG3 was lowly expressed in nasopharyngeal carcinoma tissues and cells.Overexpression of MEG3 and inhibition of miR-7-5p expression increased the radiosensitivity of nasopharyngeal carcinoma cells and promoted radiation-induced cell apoptosis.MEG3 could targetedly regulate the miR-7-5p expression.Overexpression of miR-7-5p reversed the effect of overexpression of MEG3 on the sensitization of nasopharyngeal carcinoma cells and the promotion of apoptosis induced by radiation exposure.Conclusions Overexpression of MEG3 increases the radiosensitivity of nasopharyngeal carcinoma cells and promotes radiation-induced cell apoptosis.The mechanism may be related to the down-regulation of miR-7-5p expression.
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Objective To evaluate the clinical efficacy of radical surgery combined with irradiation in the treatment of rectal cancer and its effect on the angiogenesis and survival rate.Methods A total of 200 colorectal cancer patients admitted to Zhengzhou Central Hospital from March,2014 to March,2015 were recruited and divided into the observation group (n=105) and control group (n=95) by using random number table method.In the control group,radical surgery was performed,and radical surgery combined with irradiation was conducted in the observation group.The clinical efficacy,the serum levels of vascular endothelial growth factor-C (VEGF-C) and prostaglandin E2(PGE2) were statistically compared between the control and observation groups.The changes of the microvascular morphology and microvessel density (MVD) in the rectal cancer tissues were observed and recorded.The 3-year survival rate was calculated during postoperative follow-up.Results After corresponding treatment,the clinical overall response rate was 86.67％ in the observation group,and 70.53％ in the control group (P＞0.05).The 2-year survival rate did not significantly differ between two groups (P＞0.05).The 3-year survival rate in the observation group was significantly higher than that in the control group (P＜0.05).After treatment,the serum levels of VEGF-C and PGE2 were significantly improved in two groups (both P＜0.05).In the observation group,the serum levels of VEGF-C and PGE2 were significantly lower compared with those in the control group (both P＜0.05).The microvessel morphology in the cancer tissues remarkably differed between two groups.The microvessel diameter did not significantly differ,whereas the lumen diameter in the observation group was significantly smaller than that in the control group.The MVD in the observation group was 12.25±3.35,significantly lower than 28.14± 17.26 in the control group (P＜0.05).Conclusion Radical surgery combined with irradiation is an efficacious treatment of rectal cancer,which can effectively improve the serum levels of VEGF-C and PGE2,decrease the MVD,reduce the lumen diameter in the cancer tissues,lower the angiogenesis in rectal cancer and enhance the survival rate,which deserves widespread application in clinical practice.
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Objective@#To investigate the relationship between UGT1A1*6, UGT1A1*28, UGT1A1*60 and UGT1A1*93 polymorphisms and irinotecan-induced severe adverse reactions(grade 3-4 delayed diarrhea and neutropenia) in Chinese cancer patients.@*Methods@#A total of 141 cancer patients treated with irinotecan were enrolled in this study. Peripheral venous blood was collected and genomic DNA was extracted. The genetic polymorphisms of UGT1A1*6, UGT1A1*28, UGT1A1*60 and UGT1A1*93 were analyzed by PCR and direct sequencing. The adverse reactions during chemotherapy were observed and recorded. The incidence of severe adverse reactions was compared among patients with different genotypes.@*Results@#Among 141 patients, the cases with UGT1A1*6 GG, GA and AA genotypes were 71, 54 and 16, while those with UGT1A1*28 TA6/6, TA6/7 and TA7/7 genotypes were 105, 33 and 3, respectively. The cases with UGT1A1*60 AA, AC and CC genotypes were 52, 80 and 9, while those with UGT1A1*93 GG, GA and AA genotypes were 105, 32 and 4, respectively. The patients with grade 3-4 delayed diarrhea and neutropenia were 23 and 56, respectively. Multivariate logistic regression analysis showed that UGT1A1*6 and UGT1A1*60 genetic polymorphisms were independent factors influencing the occurrence of grade 3-4 delayed diarrhea. The risk of grade 3-4 delayed diarrhea in homozygous AA carriers of UGT1A1*6 increased 3.79 times compared with that in wild-type GG carriers (95%CI: 1.35-10.67). Moreover, the risk of grade 3-4 delayed diarrhea in homozygous CC carriers of UGT1A1*60 was 20.42 times compared with that in wild-type AA carriers (95%CI: 3.52-118.33). In addition, UGT1A1*28 genetic polymorphism was an independent factor of the occurrence of grade 3-4 neutropenia. The patients with homozygous TA7/7 carriers of UGT1A1*28 had an 1.61 times higher risk of grade 3-4 neutropenia compared with those with wild-type TA6/6 carriers (95%CI: 1.44-12.65). There was no correlation between UGT1A1*93 genetic polymorphism and severe adverse reactions caused by irinotecan.@*Conclusion@#The cancer patients who carried UGT1A1*6, UGT1A1*28 and UGT1A1*60 gene polymorphisms have high risk of severe adverse events caused by irinotecan-based chemotherapy.