ABSTRACT
Objective:To analyze the advantages of IPSA combined with increasing cervical center dose in intracavitary and interstitial brachytherapy (IC/IS) for locally advanced cervical cancer.Methods:A total of 46 stage Ⅱ B cervical cancer patients with, local lesion size≥5 cm after 45 Gy/25f external intensity-modulated radiotherapy (IMRT) were recruited. Uterine tandem and needles were implanted, CT was performed, and then HR-CTV, rectum, bladder, sigmoid colon and the area of cervix increased dose (HR-cervix) were delineated, IPSA was used for optimization. According to whether the dose of HR-cervix was increased or not, all patients were divided into IC/IS+ HR-cervix group (group A) and IC/IS group (group B). The differences in dosimetric parameters were compared between two groups. Results:The relative uterine tandem dwell time was significantly extended in group A ( P<0.001). In group B, the V 150% and V 200% volumes of HR-cervix were increased from 63.94% and 30.80% to 91.54% and 64.06%. The D 90% and D 100% in group A were significantly lower than those in group B (both P<0.05). There was no statistical difference in organ at risk (OAR) dose. Conclusion:IPSA combined with increasing cervical center dose can meet the HR-CTV D 90% dose requirement, normal tissue dose limits, and can escalate the doses to local areas of the cervix.
ABSTRACT
Objective: To use autophagy inhibitors combined with radiation to treat the oral squamous cell carcinoma CAL-27 and KB cells,and to explore the influence of autophagy in the oral cancer radiation sensitivity and its mechanisms. Methods:The human oral squamous cell carcinoma CAL-27 and KB cells were divided into control group,CQ group,3-MA group,IR group,CQ+IR group,and 3-MA+IR group. The survival rate was detected by MTT method and the autophagy of CAL-27 cells was observed by immunofluorescence method and laser scanning confocal microscope.The expression levels of LC3 and beclin-1 were detected by Western blotting method. The apoptotic rate was determined by flow cytometry with Annexin Ⅴ/PI doulde staining. Results:Compared with IR group,the survival rates in 3-MA + IR and CQ+ IR groups were signifcantly decreased (P < 0.05 ).The autophagy levels of cells in IR group were significantly higher than those in control group, CQ group, 3-MA group,CQ+IR group,and 3-MA+IR group (P <0.05).The expression levels of LC3 and beclin-1 proteins in IR group were significantly higher than those in control group,CQ+ IR group,and 3-MA+ IR group (P < 0.05). The apoptotic rates in IR,3-MA+ IR,and CQ+ IR groups were markedly higher than those in control group. Compared with IR group,the apoptotic rates in CQ+IR and 3-MA+IR groups were significantly increased (P <0.05).Conclusion:Radiotherapy can induce the increase of autophagy level of oral squamous cell carcinoma cells. Inhibiors of autophagy can increase the radio-sensitivity of oral squamous cell carcinoma cells by inhibiting the proliferation and inducing the apoptosis.
ABSTRACT
Objective To construct five shRNA-expression plasmids and to investigate the expression of Smad2 in TGF-?/ Smads signal transduction treated with shRNA-expression plasmid.Methods Five shRNA-Smad2 DNA sequences from mRNA sequence of mouse Smad2 gene were designed and synthesized.DNA oligonucleotides encoding an appropriate shRNA were inserted to shRNA expression vector respectively.Five shRNA-Smad2 expression plasmids were obtained and then transfected into NIH/3T3 cells.The suppressed expression of Smad2 was assessed by RT-PCR and Western-blotting.Results The shRNA-expression plasmid numbered 2.4 could markedly reduce the expression of Smad2.The suppression effect of the RNAi-pool composed of four different plasmids was more obvious than that of any single.Conclusion The shRNA-expression plasmids were successfully constructed,which could specifically and effectively suppress the expression of Smad2.The method of using a mixture of RNAi plasmids to improve the RNAi efficiency was established.