Objective To investigate the biological effects of nonthermal plasma (NTP) combined with X-ray irradiation on human hepatocellular carcinoma in nude mice.Methods By subcutaneous inoculation, tumor models of human hepatocellular carcinoma HepG2 in nude mice were established, and these mice were divided into control group, NTP treatment group, X-ray irradiation group, combined treatment group.The changes of tumor microenvironment were observed using hematoxylin-eosin (HE) staining.The terminal deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) was used to determine the level of neuronal apoptosis in tumor tissues.The expression of metal matrix proteinase-2 (MMP-2) was detected by immunohistochemical assay.Transmission electron microscope was used to observe cell structure changes.Results The final tumor volumes of control group, NTP treatment group, X-ray irradiation group, combined treatment group were (543.96±108.45), (436.54±65.49), (351.66±56.68), (281.97±35.60)mm3, with a statistically significant difference (F=9.63, P=0.01), and the difference between X-ray radiation group and the combination treatment group was significant (P=0.05).HE staining showed that there was a larger area of necrosis in the combined treatment group compared with the other groups.TUNEL showed that the apoptotic indexes were (0.95±0.13)%, (5.82±0.26)%, (7.53±0.43)%, (11.07±0.35)% respectively, with a statistically significant difference (F=547.76, P=0.00), and the difference between X-ray radiation group and the combination treatment group was statistically significant (P=0.00).The immune scores of each group were 12, 9, 9, 2.Electron microscopic observation showed that there were more apoptotic bodies in the combined treatment group than those in the other groups, accompanied by mitochondrial edema.Conclusion NTP and X-ray irradiation therapy in the treatment of human hepatocellular carcinoma in nude mice model has a synergistic effect.Probably, it can be a new type of treatment in curing cancers.

The number of people needed to accept radiotherapy is increasing with the higher incidence of tumor,and the continuous development of radiation therapy technology has extended the longterm survival of patients.Avoiding the occurrence of radiation damage is particularly important.Since NF-κB plays an important role in gene transcription and regulation of radiation damage,this article introduced the structure,activation and function of NF-κB,reviewed the findings of NF-κB alterations in radiation injuries of brain and lung,and sketched the studies of NF-κB inhibitor.

Prophylactic cranial irradiation is an effective means of dealing with brain metastasis of cancer,which can reduce the incidence of brain metastasis by killing the micrometastasis and then improve the prognosis.The effectiveness has been verified in small cell lung cancer,but the application is still in the exploration in non-small cell lung cancer (NSCLC) and breast cancer.Prophylactic cranial irradiation is expected to become the conventional treatment for patients with NSCLC of ⅢA-N2 stage after operation and adjuvant chemotherapy or breast cancer of epithelial growth factor receptor-positive after receiving trastuzumab.

The formation and progression of tumor is inseparable from the changes of cell cycle regulatory proteins.The G2-M period block effect of tumor cells is especially important in slowing the growth of tumor and improving the curative effect.DNA damage receptor,signal transduction factor and effectors are the classical pathways to mediate G2 phase arrest of tumor cells,and have the potential to be new targets for tumor therapy.

Fat mass and obesity associated gene (FTO) has been identified as a novel gene related with obesity in recent years.A large amount of studies report the significant association between FTO expression level and energy metabolism.Besides,epidemiological studies and meta-analysis studies indicate the possibility that FTO gene polymorphism is related with cancer risk such as pancreatic cancer,endometrial cancer,breast cancer and so on.Taken account of the special energy metabolism in cancer cells which is different from that in normal cells,it is rather a novel and hot hypothesis to be investigated that FTO plays an important role in regulating energy metabolism of cancers.

External-beam radiotherapy is one of the principle treatment options for localized prostate cancer. Conventionally fractionated radiotherapy is widely used in clinical practice. Studies have shown that prostate cancer is highly sensitive to hypofractionated radiotherapy, also known as stereotactic body radiotherapy (SBRT), and increasing radiotherapy dose can significantly improve the local control rate of tumor. A number of recently completed researches have shown that SBRT is as effective as conventionally fractionated radiotherapy. In terms of radiation toxicity, the short-term toxicity of SBRT is more obvious than that of conventionally fractionated radiotherapy, but there is no significant difference in long-term toxicity. SBRT can provide more convenience for patients, and the medical cost is lower, so it has a great clinical application prospect.

Objective To establish and investigate C57 BL/6 mice model of radiation induced heart injury and ser-um marker. Methods Twenty eight female C57BL/6 mice were randomly divided into 3 groups:normal group (n=4 ) , 18 Gy radiation therapy group ( n=12 ) , 25 Gy radiation therapy group ( n=12 ) . The mice were weighed every week. Respectively, 0, 8 and 16 weeks after irradiation, the pathological changes of myocardial tissue were observed by hemetoxylin-eosin( HE) staining and made pathological score. Inferior vena cava blood was collected to take cardiac troponin I ( cTnI) test. Results Compared with the normal group,the weight of radiation group went down first then went up slowly. The myocardial tissue from mice had obvious histopathological changes. Acute in-flammation was the main change in the early days. At the late stage, progressive fibrosis was the main characteris-tic. With the increase of the dose, the inflammatory reaction and fibrosis degree had aggravated, pathological chan-ges had occurred earlier. cTnI showed a trend of higher performance over time, and had a correlation with patholo-gy. Conclusion We successfully established radiation induced myocaridal injury model. As a noninvasive serum marker, cTnI can be used as the evaluation standard of radiation induced myocardial injury animal model.

Objective To evaluate the effect of Fat Mass and Obesity Associated (FTO) gene on radiosensitivity of human glioma cell A172 and investigate its potential mechanism by changing the expression of FTO gene.Methods Cells were divided into five groups according to their FTO protein expression level.The normal expression group was recorded as A172 Group,the low-expression and its negative control group was A172/siRNA and A172/NC Group,and the over-expression and its negative control group was A172/FTO and A172/PC group.FTO protein expressions were assayed by Western blot in A172 Group after irradiation.Clonogenic assay was executed to evaluate the relationship between FTO gene and radiosensitivity.Immunofluorescence and Western blot assay were applied to detect the proteins of DNA damage and repair.Results FTO protein expression level in A172 Group was significantly related to the irradiation dose and the time post-irradiation.The radiosensitization ratio (SERD0) of A172/siRNA and A172/FTO group were 1.829 and 0.812 respectively.Not only the number of γ-H2AX foci increased (t =-21.884,P ＜ 0.05) in A172/siRNA 1 h post-irradiation but the decreases of p-p95/NBS1 and Ku80 proteins were also detected (t =24.731,23.293,P ＜ 0.05) together with the increase of Rad50 protein (t =3.140,P ＜ 0.05).But the expressions of these proteins in A172/FTO group were opposite to the above phenomenon (t =0.642,-8.364,26.829,P ＜ 0.05).Conclusions FTO gene is a radiation-resistant gene,which may because the regulation of FTO gene could alter the primary injury and DNA damage repair in the irradiated tumor cells.

Objective Based on the published articles,this paper aims to study the pattern and probability of lymph nodes metastasis in nasopharyngeal carcinoma (NPC) and establish a radiotherapy standard for selecting and delineation of clinical target volume of neck lymphatics for NPC patients with N0 or N1.Methods Clinical trials about NPC by MRI as the main or only diagnostic imaging way were collected and extracted from database,such as WanFang,CBM,PubMed,Cochrane Library.Statistical analyses were performed using Stata software,version 12.0.Results Twenty-one clinical trials from 963 original articles were included in this analysis.The most commonly involved regions included retropharyngeal (67％) and level Ⅱ lymph nodes (71％).The overall probability of levels Ⅲ,Ⅳ and Ⅴnodal involvement were 37％,14％ and 21％,respectively.Low-risk node groups included levels ⅠA,ⅠB,Ⅵ nodes,and the rates of lymph node metastasis were 0,2％,2％ and 1％,respectively.Nodal metastases followed an orderly pattern of top-down,and the probability of skip metastasis between levels varied between 0.5％ ～7.9％.Conclusion Lymph node metastasis in NPC follows a predictable and orderly pattern.The rarity of metastasis in certain nodal groups andskip metastasis suggest that reduced treatment volume is feasible in conformal radiotherapy for NPC patients with No or N1.

Objective To investigate the dynamic changes of nuclear factor-κB(NF-κB) during brain injury of irradiated rats.Methods According to the random number table method,82 healthy Sprague-Dawley rats were divided into two groups:50 rats in the irradiation group and the other 32 rats in the control group given sham-irradiation.The whole brains of rats in the irradiation group were irradiated with a single dose of 20 Gy electron beam to establish an animal model of radiation-induced brain injury.All brain tissues were respectively taken out 1,3,7,14 and 28 d after irradiation.The quantificational real-time-polymerase chain reaction (QRT-PCR) was used to detect the expressions of the NF-κB mRNA while the expression of NF-κB protein was analyzed by ELISA and Western blot.The positioning expression of NF-κB protein in the hippocampus was measured with immunohistochemical staining.Results In the irradiation group,the expression of NF-κB mRNA significantly increased at 3 and 7 d following irradiation (t =37.79,35.30,P ＜ 0.05) and it approached a peak value on the third day following irradiation.The expression of NF-κB protein in whole brain tissues after irradiation was up-regulated and reached a peak on the first day post-irradiation and it was significantly higher than controls at 1,3,7,14 d after irradiation (t =30.94,14.87,27.17,13.27,P ＜ 0.05) then declined and dropped to the normal level by 28 d.The results of immunohistochemical staining showed that the number of NF-κB positive cells in the hippocampus increased at 1,3 and 7 d following irradiation (t =-8.49,-4.47,-3.46,P ＜ 0.05).Conclusions After irradiation,the expressions of NF-κB mRNA and corresponding protein first increase and then later decrease,which promotes the development of brain injury.