The caudal-type homeobox gene is a member of homeobox gene—Para-HOX family,including CDX1,CDX2 and CDX4.As a transcriptional factor,CDX plays an important role in embryo development,hematopoietic system formation,intestinal epithelium tissue development and so forth.The abnormal expression of CDX is usually closely related with tumorigenesis.Researching the relationship between CDX and tumors will contribute to tumor diagnosis and treatment.

Objective To design and screen small interefere RNA (siRNA) targeting of HOXA7,and to investigate the effect of the siRNA on human lung cancer LETP-a-2 cells proliferation and apoptosis in vitro.Methods Three pairs of siRNA targeting of HOXA7 and one pair of siRNA for negative control were transfected respectively into LETP-a-2 cells through cationic liposome.The mRNA and proteion expression levels of HOXA7 were observed by reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis.The effect of HOXA7 siRNA on growth and apoptosis of LETP-a-2 cells were measured by MTT and flow cytometry.Results All the three pairs of siRNA could inhibit HOXA7 expression effectively,among which siRNA2 got the best effects,the silence rates were (57.344±4.743) ％ on mRNA level and (52.219±0.550) ％ on protein leval.The proliferation was inhibited and the apoptosis was promoted by the siRNA targeting HOXA7 in LETP-a-2 cells,among which siRNA2 got the favourite results,the inhibitory rate was (48.144±4.992) ％ and the apoptosis rate was (26.613±0.612) ％.Conclusion The siRNA2 targeting of HOXA7 enrolls in promoting apoptosis and inhibiting grows of LETP-a-2 cells,indicating that manipulation of HOXA7 expression may be a potential therapeutic strategy for cancer.

Objective Based on the anthropomorphic phantom experiment and Monte Carlo simulation, the patients’ skin dose, professionals’ dose, and spatial distribution of DSA (Digital Subtraction Angiography) radiation field in an intervention procedure, was performed, in order to provide the basis for the inference of patients’ skin injury and professionals’ radiation protection in intervention procedure. Methods In the simulation experiment, a PBU-60 anthropomorphic phantom was used as the patient and the skin dose of patient’s abdomen was measured by TLD (Thermoluminescence Dosimeters). X-ray and gamma radiation dosimeter (AT1121) was applied to measure the spatial distribution of DSA radiation field, which was verified using Monte Carlo software MCNP meanwhile. Furthermore, the radiation dosimetry of operative staffs at different stations and under different protection conditions was studied experimentally. Results The experimental measurements showed that the maximum skin dose of patients every 5-minute fluoroscopy was 18.62 mGy under the irradiation of PA in an abdominal interventional procedure. The results of Monte Carlo simulation and measurement experiments showed that the spatial distribution of DSA radiation fieldis similar to the butterfly distribution, which is related to distance and angle. The experimental results showed that the dose rate decreases exponentially with the increase of lead equivalent. Conclusion It is very significant to carry out skin dose measurementof patients during interventional surgery and follow-up patients with high dose after surgery. In interventional surgery, doctors should try to avoid the station of high dose rate. However, it is necessary to strengthen the radiation protection of the operator and the first assistant. Under the dual protections of bedside lead protective equipment and personal protective equipment, the exposure dose of intervention personnel can be significantly reduced.