DACT2 gene promoter area methylation status and mRNA expression in renal cell carcinoma / 重庆医学

Objective To explore the role of the DACT2 gene in the occurrence and development of renal cell carcinoma(RCC).Methods The samples of RCC tissues and corresponding tumor-adjacent tissues after radical operation and normal kidney tissues were collected.The methylation specific PCR (MSP) and real time fluorescence reverse transcriptase-PCR (RT-PCR) methods were adopted to detect the methylation status and mRNA expression of DACT2.The streptavidin-peroxidase (SP) method labeled by immunohistochemistry peroxidase was used to examine the expression of β-catenin protein.Then the relationship between DACT2 gene methylation status and mRNA expression with the clinicopathologic characteristics was analyzed.The relationship between DACT2 gene methylation with mRNA and β-catenin expression was analysed,as well.Results The DACT2 mRNA relative expression level in RCC tissues was 0.427±0.025,which was significantly lower than (0.801±0.047) in tumor-adjacent tissues and (0.872±0.022) in normal tissue,the positive rate of DACT2 gene methylation in RCC tissues was 45.76%,which was significantly higher than 6.78% in tumor-adjacent tissues and 5.08% in normal tissues,the difference was statistically significant (P0.05).The DACT2 gene mRNA expression level in RCC tissues and promoter area methylation occurrence rate had no obvious correlation with the clinical data such as patients age,gender,tumor size,clinical stage and Fuhrman grade (P>0.05).The DACT2 gene mRNA relative level in the methylation group was lower than that in the non-methylation group,the difference was statistically significant (P<0.05).The expression rate of β-catenin protein in cytoplasma in RCC tissues was higher than that in the tumor-adjacent tissues and normal tissues,the difference was statistically significant (P<0.05),moreover,DACT2 gen methylation had a positive correlation with β-catenin protein expression (r=0.324,P=0.012).Conclusion The decrease of DACT2 gene promoter area methylation and mRNA relative expression level may participate in the RCC occurrence,but has no relationship with RCC clinical progression.Methylation occurred in DACT2 gene promoter area may be one of reasons causing mRNA relative expression decrase.DACT2 gene methylation occurrence in RCC tissue might be related to the high expression of β-catenin.

The research of IMRT plan optimization on dose limitation of sub regional auditory organ / 中华放射肿瘤学杂志

Objective To investigate the effects of reducing the auditory organ dose by limitation of sub regional auditory organ in IMRT plan. Methods Total 223 cases of nasopharyngeal carcinoma patients were divided into group A and group B. In group A, the IMRT plans of 114 patients were designed by limiting overall auditory organ dose. In group B, the IMRT plans of 109 patients were designed by limiting sub regional auditory organ dose. According to the Clinical prescription, the IMRT plans were designed. Paried t?test was difference between groups. Results By comparing the two groups of auditory organ dose, in all stages, the tympanic cavity Dmean average in group B decreased by T1 vs. 17?? 7%,T2 vs. 22?? 4%,T3 vs. 15?? 7% and T4 vs. 14?? 2% ( P= 0?? 000,0?? 000,0?? 000,0?? 000);cochlea Dmean average decreased by T1 vs. 11?? 0%, T2 vs. 20?? 1%, T3 vs. 10?? 0% and T4 vs. 9?? 0%(P= 0?? 004,0?? 000,0?? 007,0?? 036);vestibule Dmean average decreased by T1 vs. 22?? 6%, T2 vs. 31?? 8%, T3 vs. 20?? 6% and T4 vs. 21?? 4%, significantly less than in group A (P= 0?? 000,0?? 000,0?? 000,0?? 000). The bony portion of eustachian tube Dmean average in group B decreased were not significantly less than in group A (decreased by 3?? 4%,6?? 8%,3?? 6%,0?? 1%;P= 0?? 291, 0?? 006,0?? 155,0?? 963). Conclusions In IMRT plan, optimization on dose limitation of sub regional auditory organs were used to reduce the auditory organ dose and decrease the radiation damage to auditory organ.

miR-222 can inhibit the autophagy of renal cell carcinoma cells through down-regulating the expression of DDIT4 / 中国癌症杂志

Background and purpose:MicroRNA (miRNA, miR) plays an important regulatory role in cancer. miR-222 is reported to be up-regulated in various tumors, but its role in renal cell carcinoma (RCC) remains unclear. In this study, we detected the expression of miR-222 in both RCC and adjacent tissue samples. The aim of this study was to investigate the role of miR-222 in RCC. Methods:The expression levels of miR-222 in RCC tissue samples were quantified by quantitative real-time polymerase chain reaction (qRT-PCR). DDIT4 and LC3-Ⅱ protein expressions were determined by Western blot. Dual luciferase assay was performed to verify the target of miR-222. EGFP-LC3 microscopy assay was performed to assess autophagy. Results:Results from qRT-PCR showed that the expression of miR-222 was up-regulated in RCC tissues. Knockdown of miR-222 with speciifc antagomiR decreased the cell viability of 786-O cells, whereas overexpression of miR-222 increased the cell viability (P<0.01). The levels of DDIT4 were up-regulated in 786-O cells transfected with miR-222 antagomiR, whereas overexpression of miR-222 induced the down-regulation of DDIT4 expression. Data from dual luciferase assay indicated that miR-222 directly targeted the expression of DDIT4. Consistently, the expression of DDIT4 in RCC tissues was down-regulated compared with adjacent tissues. Knockdown of miR-222 in 786-O cells induced a signiifcant increase of autophagosome formation and LC3 lipidation.These results supported that miR-222 could inhibit autophagy in RCC cells, which may affect the clinical characteristcs of RCC. Conclusion: miR-222 is up-regulated in RCC and can inhibit the autophagy of RCC cells through down-regulating the expression of DDIT4.

Hinokitiol induces clear cell renal cancer 786-O cell apoptosis via autophagy induction / 中国肿瘤临床

Objective: To investigate the effects of hinokitiol on the proliferative inhibition and apoptosis induction in human clear cell renal cancer 786-O cells. Methods:CCK-8 assays were performed to analyze the effects of hinokitiol on the proliferation of 786-O cells. The apoptosis rate was determined by flow cytometry. EGFP-LC3 microscopy assays were performed to assess the autoph-agy flux. Cleaved Caspase-3, LC3, and P62 were detected by Western blot. Results: Hinokitiol could inhibit the proliferation of the 786-O cells and could induce cell apoptosis via Caspase pathway. Hinokitiol induced the autophagy of 786-O cells, increased LC3 ex-pression, and downregulated P62 expression. Conclusion: Hinokitiol can inhibit the proliferation of 786-O cells and can induce cell apoptosis via autophagy induction.

Effects of dose limitation and increased protective weight on dose distribution in auditory organs during intensity-modulated radiotherapy for nasopharyngeal carcinoma / 中华放射肿瘤学杂志

Objective To investigate the protective effects of reducing average radiation dose and increasing protective weight on the auditory system (tympanic cavity,the bony portion of eustachian tube,vestibule,and cochlea) during intensity-modulated radiotherapy (IMRT) for nasopharyngeal carcinoma (NPC).Methods The planning system (ADAC Pinnacle3 8.0m) with direct machine parameter optimization was used to optimize the IMRT planning for 40 patients with NPC (stage Ⅰ + Ⅱ:20 patients ;stage Ⅲ + Ⅳ:20 patients).Without reducing the radiation dose for target volume,the IMRT planning was optimized by limiting the average dose administered to the auditory system or increasing the protective weight for the protected organs in auditory system.The protective effects were assessed by analyzing the average dose received by the auditory system.Results After limiting the average dose administered to the auditory system without reducing the radiation dose for target volume,the average dose received by the auditory system was significantly reduced (3855.5-5391.3 Gy vs 2960.3-4559.6 Gy,P =0.000 for all) ; when the protective weight for the auditory system was increased,the average dose received by the auditory system was even more reduced (3855.5-5391.3 Gy vs 2725.4-4271.4 Gy,P =0.000 for all).For all three regimens,the average dose was significantly higher in stage Ⅲ + Ⅳ patients than in stage Ⅰ + Ⅱ patients (P =0.000 for all).Conclusions For the IMRT planning for NPC,limiting the average dose administered to the auditory system can greatly reduce the average dose received by the auditory system,and increasing the protective weight for the auditory system can further reduce the average dose received by the auditory system.However,the protective effect on the auditory system may be reduced as the stage of NPC increases.

The research on expression and clinical significance of MCM2 in BTCC / 中国癌症杂志

Background and purpose:It is verifi ed that MCM2 is a specifi c marker in the cell cycle,and expressed in all cells entering into the cycle,however,no expression is found in the differentiated cells and static period cell.Therefore,in the abnormally proliferative developmental cells and mutagenic cells,MCM2 could be used to mark the status of the cells as a cellular proliferative marker,and then to be a diagnostic tool for some heterotypical pathological changes and tumors.Our study demonstrated that the expression and clinical significance of MCM2 in bladder transitional cell cancer(BTCC).Methods:The expression of MCM2 was examined by immunohistochemistry Streptavidin-Peroxidase method in 12 cases of normal bladder tissues and 42 cases of BTCC.Results:The positive expression of MCM2 in BTCC was 100%,whereas in normal tissues,no positive expression was found(P0.05).The expression of MCM2 was closely associated with tumor pathological grade(P