Objective To analyze the curative effects,late phase reactions and their prognostic factors of nasopharyngeal carcinoma (NPC) treated with radiotherapy.Methods Retrospective analysis was made for 246 cases of NPC which were confirmed by pathological diagnosis and with complete follow-up data in the first affiliated hospital of Soochow university.Kaplan-Meier method was used for analysis of survival rate and the log rank method was used to compare the survival between groups.Cox regression was used for analysing the prognostic factors.Logistic regression was used for analysing the factors which affect the late phase reactions.Results The follow-up rate was 94.6％.The 1-year,3-year,5-year overall survival (OS) were 97.97％,81.82％,67.85％.The 1-year,3-year,5-year progression-free survival (PFS) were 83.33％,70.00％,39.29％ respectively.Age (x2=6.604,P=0.010),T stage (x2 =3.670,P=0.050),N stage (x2=19.658,P =0.001) and the clinical stage (x2 =4.626,P =0.031) were the prognostic factors for the OS.Cox multi-variate analysis showed that the independent prognostic factors for the OS were clinical stage and age.Logistic regression analysis showed that the independent prognostic factors for the late phase reactions were age and rehabilitation time.Conclusion The main factors for the long term survival of NPC patients after radiotherapy are early TNM stage and young age.Patients with younger age and longer rehabilitation time have lower incidence of late phase reactions.

The curriculum of oncology radiotherapy covers basic radiology,clinical oncology and other aspects.With the development of new radiation therapy technology and the extensive application of computer technology in the field of radiotherapy,the traditional lecture-based teaching model has not adapted to the rapid development of the needs of oncology radiotherapy any more.Teachers in the first affiliated hospital of Soochow university integrated computer multimedia with problem-based learning in the teaching of oncology radiotherapy.With those innovations,the quality of teaching as well as the creative and self-learning abilities of students have been enhanced.

Objective To compare the radiosensitivity effect of celecoxib on oln93 and u373 cells,and to explore the related mechanism.Methods Both oln93 cells and u373 cells were respectively divided into control group,drug group,radiation group and combined group when treated with celecoxib and irradiation.Cell survival ratio was evaluated by MTT assay and clogenic assay.Flow cytometry and Western blot assay were used to measure cell cycle and protein expression.Results Celecoxib had a similar effect on oln93 and u373 cells in enhancing the radiosensitivity (t =2.215-30.996,P ＜ 0.05 ; t =0.383-11.732,P＜0.05)and blocking cellcycle in G0/G1(t=-6.1-5.141,P＜0.05).Compared with the radiation group,the combined group showed S phase arrest(t =-18.174,P ＜ 0.05),and increase of Cyclin A protein (t =-8.087,P ＜ 0.05) in oln93 cells,and G2/M arrest and decrease of Cyclin B1 and DNA-PKcs and MRE11 protein (t =-8.838-10.45,P ＜ 0.05) in u373 cells.Conclusions Celecoxib illustrates a more sensitive radiosensitivity to u373 cells by regulating its cell cycle and DNA damage repair.

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 To observe the differences of the radio-biological characteristics between the human malignant glioma cell line SHG-44 and its progeny cells SHG-4410 Gy and to probe the underlying mechanism.Methods The SHG-4410 Gy cells were the progeny of SHG cells that had been irradiated with 10 Gy X-rays and then passaged for 15 generations.The radiosensitivity of SHG-44 and SHG-4410 Gy wre measured by clonogenic assay and the multi-target single-hit model was used to fit the survival curve.The cell cycle redistribution and apoptosis were analyzed by flow cytometry assay.Quantitative Real Time-PCR (qRT-PCR) was used to determine the relative levels of cyclin B1 mRNA and miR-21.Stat3 protein levels were detected by Western blot.Results The values of D0,Dq and SF2 of SHG-4410 Gy cells were significantly higher than those of SHG-44 cells.Flow cytometric analysis showed that there was less G2/M phase arrest in SHG-4410 Gy (F =22.21,P ＜ 0.05).Radiation-induced early apoptotic population was increased from (17.60 ± 0.26) ％ to (28.00 ± 0.36) ％ for SHG-44 cells,but increased from only (4.20 ± 0.30)％ to (5.17 ± 0.65)％ for SHG-4410 Gy.miR-21 in SHG-4410 Gy cells were increased by 1.44 fold of SHG-44 cells,which was associated with the increase of Stat3 protein expression.Conclusions Radioresistance is observed in the progeny of human malignant glioma cell line SHG-44 which had been irradiated with 10 Gy X-rays.The underlying mechanisms may be relative to the upregulation of cyclin B1 that acts as a key downstream gene in the signaling pathway of G2/M phase transition.In addition,the upregulation of miR-21 may be involved in the apoptosis of SHG-4410 Gy cells.

ObjectiveThe purpose of the study was to observe and analysis the actual dosage of patients with breast cancer using metal oxide semiconductor field effect transistor (MOSFET) detector.MethodsFirst, Phantom measurements were performed to investigate dose distribution in the area of the junction in a half-field matching method and the influence of factors related to the accelerator. In vivo dose measurements were performed for patients with breast cancer to investigate the skin dose and the junction of supraclavicular-axillary field and tangential field in 6 MV X-ray beams. ResultsPhantom measurements showed that the relative deviation in the junction were within + 3％, and the dose distributions in the junction area depended on the matching field direction (x or y). In vivo measurement of tangential region for patients showed that, the maximum dose deviation between measurement and calculation was -30. 39％,the minimum deviation was - 18. 85％, the average dose deviation was -24. 76％. The dose deviation of tangential fields for patients with breast-conserving surgery was larger than that patients with radical surgery (t =2. 40 ,P＜0. 05), while dose deviation of supraclavicular-axillary fields was not significantly different. The average values of 15 fraction in the junction area showed more stable than one individual measurement.ConclusionsIt is important to real-time, in vivo measurement of radiation dose during radiotherapy in patients with breast cancer, and change treatment plan in time, to ensure the accuracy of target dose.

BACKGROUND: The investigation of culturing, passaging and establishing human limbal stem cells can strengthen the recognition of the stem cells and provide the enough cellular reserve for the basic and clinical research of limbal stem cell transplantation.OBJECTIVE: To explore a method of pessaging and establishing cell line of human limbal stem cells cultured in vitro.DESIGN: Randomized controlled observation.SETTING: Gannan Medical College.MATERIALS: The experiment was performed at Scientific Center of Gannan Medical College and the National Key Laboratory of Ophthalmology Hospital Affiliated to Sun Yat-Sen University from June 2003 to April 2004. Fresh human limbus corneae were isolated from two healthy donors. Procedures were performed according to the informed consent of the donors. Main reagents contained RPMI-1640 (Sigma R8755, containing L-glutamine) and 200 g/L fetal calf serum (FCS) (Gibco 16140-071). DMEM medium, chondroitin sulfatase and human epidermal growth factor (hEGF) were purchased from Sigma Co. USA; HEPES and DMSO were bought from Gibco, USA; 100% glycerinum was purchased from Yunjia Huangpu Pharmaceutical Product Limited Company, PRC; glutaraldehyde was bought from E.Merk, Germany; Alcohol, chlorhydric acid, acetone and methyl aldehyde were purchased from Beijing Chemical Agent Company, PRC; 0.25% parenzyme was bought from Shanghai Xinhua Pharmaceutical Factory, PRC.Above-mentioned reagents were analytical pure grade.METHODS: After digestion, human limbal tissues in limbal basilar part with an abundant pigment were cultured in the culture flask containing RPMI-1640 and 200 g/L FCS and in culture dish containing amniotic extracellular matrix (AECM) as the cultural supporter. Primary and passage cells were observed under light microscope and scanning electron microscope (SEM). The revival ratio of stem cell refrigeration of every generation was calculated by the trypanblau exclusion experiment.MAIN OUTCOME MEASURES: ① Observational results of limbal stem cells during the primary culture and serial subcultivation in vitro, and ② revival ratio of stem cell refrigeration.RESULTS: ①Findings of primary culture: Most limbal stem cells in the culture flask had the adherence and were arrayed uniformly sparsely to form monolayer and adhered to the bottom of culture flask under the inverted phase contrast microscope after 1-day culture. ② Findings of serial subcultivation: After human epidermal growth factor (hEGF) was added into the second passage, cells were scattered into the monolayer and adhered to grow quickly.Morphological variability of all the cells increased obviously when passage the 30th generation. The cellular volume was obviously increasing, and the round or irregular round cells gathered together. The 33rd generation human limbal stem cells still could vigorously differentiate, proliferate and grow in ACEM. ③ The revival ratio of stem cell refrigeration was 82.2%.CONCLUSION: The human limbal stem cell lines were preliminarily established by culturing and freezing the cells of 33 generations in vitro. The human limbal stem cell lines preferred to grow in the culture dish containing AECM as the cultural supporter.

Objective To investigate the radiosensitizing effect of knock-down the expression of miR-21 on human SHG-44 glioma cells and explore the possible mechanism. Methods Antisense oligonuleotidas of miR-21, mediated by LipofectamineTM 2000, were transfected to SHG-44 cells. Three groups were: blank control group ( mock group), negative control and antisense transfected group ( AS-miR-21 gorup). Cells of each group were irradiated with 6 MeV X-rays at the doses of 0,1,2,4,6 and 8 Gy.Dose-suvivial curve was established by colony-forming assay. The influence of AS-miR-21 on cell cycle and cell apoptosis was analyzed by flow cytometry assay after 6 Gy irradiation. Results The value of D0 and Dq of AS-miR-21 group declined obviously compared with the mock group and negative control group. Flow cytometric analysis showed that cell cycle distribution changed( G0/G1 phase arrest, S phase decreased)after transfected with AS-miR-21 (t = 8.18, -4.52,P ＜ 0.05 ). The sensitization enhancement ratios of D0 and Dq were 1.32 and 2.10 respectively. Apoptosis assay showed the early apoptosis rate was signiflcantely increased in AS-miR-21 、irradition alone and combined group than mock control group( t = 20.14,11.11,50.07, P ＜ 0.05). Conclusions AS-miR-21 can enhance the radiosensitivity of human glioma cells SHG-44 by promoting cell apoptosis and faciliating cell cycle redistribution.

Objective To investigate the effects of radiosensitivity enhancement and inhibition of migration ability of human lung adenocarcinoma cells by celecoxib,a selective cyclooxygenase (COX)-2 inhibitor.Methods Human lung adenocarcinoma cells of the line A549 were cultured and then inoculated into six-well plates and randomly divided into 4 groups:control group,celecoxib group administered with celecoxib at the subtoxic doses 30 and 50 μmol/L,irradiated group exposed to 0,1,2,4,6,or 8 Gy by linear accelerator,and combined treatment (celecoxib + irradiation) group.The radiosensitizing effect of celecoxib was assessed by clonogenic cell survival test.The migration ability of the A549 cells was measured by scratch-wound test and the content of metalloproteinase-2 (MMP-2) in culture supernatant was detected with ELISA.Results The sensitization enhancement ratio of the celexib group was increased dosedependently.The values of D0 ,Dq,SF2 and D0.01 of the celecoxib + irradiation group were all significantly lower than those of the irradiated group.Scratch-wound test showed that the no-scratch area of the celecoxib + irradiation group and celecoxib group were all significantly wider than those of the mere irradiation and control groups and there was a dose-dependent manner,and the no-scratch area of the celecoxib + irradiation group was wlider than that of the celecoxib group.ELISA showed that the MMP-2 levels in the supernatant of the celecoxib group and celecoxib + irradiation group were respectively significantly lower than those of the control group and mere irradiated group (t = 3.78,5.79、3.15,P ＜ 0.05),however,there was not significant difference between the mere irradiation and control groups (t = 2.73,2.38,P ＞ 0.05).Conclusions Celecoxib enhances concentration-dependently the radiosensitivity of human lung carcinoma cell and inhibits the secretion of MMP-2 of the carcinoma cells,thus inhibiting their migration ability.

Objective To investigate the dynamic changes of the contents of brain water and Ca,Fe,Cu,Zn,Mg and microvascular damage in hippocampal tissue of radiation-injured rat brain.Methods The rats were randomly divided into control group,protective group (with intraperitoneal injection of 10％ MgSO4,400 mg/kg body weight + a single dose of 20 Gy electron beam irradiation in whole brain) and irradiation alone group (with intraperitoneal injection of normal saline,400 mg/kg body weight + a single dose of 20 Gy electron beam irradiation to the entire brain) with 18 rats assigned to each group and 3 rats sampled at each time point.Radiation-induced brain injury (RBI) was modeled by irradiating the rat' s whole brain with 5 MeV electrons.A dry-wet weight method was used to detect brain water content (BWC),and the level of microvascular damage was detected with HE staining of brain tissue slices,and the contents of Ca,Fe,Cu,Zn,Mg in hippocampus were detected with inductively coupled plasma atomic emission spectroscopy at different time points after radiation.Results BWC in the irradiated rats at 7,14 and 30 d post-irradiation was higher than that of control group (t =3.21,-2.11,2.82,P ＜0.05),andBWC in the protective group was less than that in the irradiated group (t =2.84,4.33,1.90,P ＜ 0.05).Microvascular thrombosis was induced in the radiated brain but this thrombosis was reduced by MgSO4.Thecontents of Ca and Fe in the brain tissue after 1,3,7 d of irradiation was higher than that of control group(t =11.41,6.81,14.03,17.17,6.89,9.12 and 5.43,5.66,3.60,P ＜ 0.05),and the content of Cain the protective group at various time post-irradiation was less than that in the irradiated group (t =5.35,5.28,11.02,14.26,5.68,9.10,P ＜0.05).The content of Cu (1,7,14,60 d post-irradiation) andZn (1,7,14,30,60 d post-irradiation) of the irradiated group was less than that of the control group(t =4.24,3.76,4.76,3.86 and 5.25,4.78,26.53,6.67,11.37,P ＜ 0.05),and the content of Cuin the protective group at different time points post-irradiation was less than that of the irradiated alonegroup (t =4.23,3.57,4.01,4.73,3.78,3.44,P ＜0.05),the content of Zn in the protective group(14 d post-irradiation) was higher than that of the irradiated group (t =6.21,P ＜ 0.05).The content ofMg in the irradiated group (7 d post-irradiation) was less than that of the control group (t =5.85,P ＜0.05).Conclusions The contents of Ca,Fe,Cu and Zn were imbalanced in the radiation-injured ratbrain,and the supplement of MgSO4could recover the balance of Ca,Fe,Cu and Zn content and alleviateradiation-induced brain injury.