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Small bowel capsule endoscopy and double-balloon enteroscopy have become new methods for clinical diagnosis of radiation enteritis (RE) , especially for abnormal intestinal tissue. Targeted biopsy or interventional therapy is expected to achieve precision treatment of RE. The screening of molecular markers in biological samples has also become a new direction for RE diagnosis. Fecal microbiota transplantation has become one of the promising treatments for RE. In addition, mechanism studies based on traditional Chinese medicine, targeted cell death, and omics analysis provide rich strategies for the diagnosis and treatment of RE.
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Brain metastases are one of the most common distant metastases in patients with non-small cell lung cancer (NSCLC), and the prognosis will be extremely poor. The effect of chemotherapy and operation is limited. As a standard treatment, radiotherapy is widely used in clinical practice. Radiotherapy alone includes whole brain radiotherapy, stereotactic radiotherapy and whole brain radiotherapy combined with stereotactic radiotherapy. With the continuous development of radiotherapy and the progress of gene sequencing, radiotherapy has been combined with targeted drugs, anti-angiogenic drugs and immunodrugs in the treatment of NSCLC brain metastasis, which can improve the survival of patients with NSCLC brain metastasis.
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Objective:To investigate the prognostic factors of oligometastatic (OM) non-small cell lung cancer (NSCLC) patients and the safety and effectiveness of early radiotherapy intervention.Methods:A retrospective analysis was conducted, including 159 OM NSCLC cases (metastatic sites≤5, metastasis organs≤3) admitted to Department of Radiation Oncology in First Affiliated Hospital of Soochow University from January 2015 to December 2018. Among 159 cases, there were 107 males and 52 females, with the median age of 63 years. 137 cases were administrated via early radiotherapy intervention, and 22 cases via delayed radiotherapy intervention. The receiver operating characteristic curve (ROC) was used to determine the progression-free survival time (PFS)/overall survival time (OS) to ascertain the best cut-off value for local control and prognosis. Survival analysis was calculated by Kaplan-Meier curves, and Log rank test was used for comparison of these curves. Cox proportional hazards regression model was used for multivariate survival analysis.Results:The median follow-up time of 159 cases was 28.2 months. During the follow-up period, there were 16 cases with complete remission (10.1%), 53 cases with partial remission (33.3%), 27 cases with stable disease (17.0%), and 63 cases with progressed disease(39.6%). The local control rates at 3, 6 and 12 months were 83.9%, 59.7% and 41.0%, respectively. The median progression-free survival (PFS) of 159 patients was 8.0 months, the median survival time (OS) was 35.0 months, and 1, 2, and 3-year survival rates were 77.3%, 63.0% and 45.1%, respectively. Adverse reactions related to radiotherapy were relatively mild, mostly grade 1 and 2. PFS/OS= 0.3 is the best cut-off value for determining the patient′s local control and prognosis. The result of univariate analysis showed that gender, number of OM organs, T staging, radiotherapy intervention mode, tumor target volume absorbed dose (DT-GTVnx), PFS/OS were significantly related to median PFS ( χ2=4.175, 16.508, 4.408, 10.300, 6.842, 38.175, P<0.05); gender, pathological type, number of OM organs, initial diagnosis stage, T stage, N stage, lobectomy, radiotherapy intervention mode, tumor target volume (V-GTVnx), tumor load, local control status were significantly related to median OS ( χ2=6.672, 8.330, 21.299, 5.398, 6.874, 6.893, 5.611, 115.206, 4.017, 5.110, 21.299, P< 0.05). The result of multivariate analysis showed that delayed radiotherapy intervention ( HR=3.728, 95% CI 2.099-6.622, P<0.001) was an independent risk factor for PFS in patients with OM NSCLC, and PFS/OS>0.3 ( HR=0.123, 95% CI 0.062-0.246, P<0.001) was an independent protective factor for PFS in patients with OM NSCLC; male ( HR=1.665, 95% CI 1.024-3.043, P=0.033), high tumor burden ( HR=2.113, 95% CI 1.088-4.107, P=0.027), delayed radiotherapy interventions ( HR=15.076, 95% CI 7.925-28.680, P<0.001) were independent risk factors for OS in patients with OM NSCLC. Conclusions:OS of patients with OM NSCLC is significantly prolonged in female, low tumor burden and early radiotherapy intervention. Early radiotherapy intervention significantly improved the prognosis, and radiotherapy-related adverse reactions could be tolerated. These might suggest that local radiotherapy is safe and effective in the treatment of OM NSCLC patients.
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Lung cancer is the leading cause of cancer death worldwide as well as in China. For many years, conventional oncologic treatments such as surgery, chemotherapy, and radiotherapy (RT) have dominated the field of non-small cell lung cancer (NSCLC). The recent introduction of immunotherapy in clinical practice, led to a paradigm shift in lung cancer as in many other solid tumors. Recent pre-clinical and clinical data have shown RT may also modify antitumor immune responses through induction of immunogenic cell death and reprogramming of the tumor microenvironment. This has led many to reexamine RT as a partner therapy to immuno-oncology treatments and investigate their potential synergy in an exponentially growing number of clinical trials. Clinical trials combining radiotherapy and immunotherapy are attracting major attention, experts were invited to discuss frontier and controversial academic topics: (1) Recent developments of clinical synergy between radiation and immune checkpoint inhibitors (ICIs) in the treatment of NSCLC; (2) Will immunotherapy and radiotherapy increase the toxicity risk for cancer patients; (3) How to cope the mixed responses/disassociated responses phenomenon in checkpoint inhibition therapy to NSCLC with local ablative therapy; (4) Combining radiotherapy and immunotherapy in the treatment of NSCLC brain metastases.
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Objective:To investigate the prognostic value of TCBI in middle-aged and elderly patients with thoracic esophageal squamous cell carcinoma (ESCC) who received radiotherapy.Methods:The clinical data of 191 patients with thoracic ESCC who underwent radiotherapy in the department of Radiation Oncology of the First Affiliated Hospital of Soochow University from January 2010 to December 2015 were retrospectively analyzed. According to the TCBI value on admission [TCBI=serum triglyceride (mg/dl) × total cholesterol (mg/dl) × body weight (kg)/1 000], patients were divided into TCBI low-value group ( n=79) and TCBI high-value group ( n=112). The relationships between TCBI and clinicopathological characteristics of patients were analyzed. The Kaplan-Meier method was used to calculate the overall survival (OS). The log-rank test was adopted to compare the differences in survival between different groups. The Cox proportional hazard model was used to analyze the factors affecting the prognosis of middle-aged and elderly patients with thoracic ESCC. The receiver operating characteristics (ROC) curve was applied to verify the accuracy of TCBI for survival prediction. Results:The mean pre-radiotherapy TCBI was 1 082±945 in all patients. The cutoff value of the TCBI was 749. The patients with TCBI<749 served as the TCBI low-value group , and patients with TCBI≥749 served as the TCBI high-value group. TCBI was associated with treatment ( χ2=4.235, P=0.040) and geriatric nutritional risk index (GNRI, χ2=8.795, P=0.003). Univariate analysis suggested that male ( HR=2.220, 95% CI: 1.223-4.030, P=0.009), stage N 1-3 ( HR=1.453, 95% CI: 1.023-2.065, P=0.037), GNRI<98 ( HR=1.949, 95% CI: 1.168-3.255, P=0.011) and TCBI<749 ( HR=1.846, 95% CI: 1.298-2.627, P=0.001) were risk factors affecting OS in middle-aged and elderly patients with thoracic ESCC. Besides, postoperative adjuvant radiotherapy ( HR=0.641, 95% CI: 0.449-0.915, P=0.014) was a protective factor. Furthermore, multivariate analysis showed that male ( HR=2.147, 95% CI: 1.173-3.929, P=0.013) and TCBI<749 ( HR=1.664, 95% CI: 1.166-2.376, P=0.005) were independent risk factors for OS. Besides, postoperative adjuvant radiotherapy ( HR=0.630, 95% CI: 0.439-0.903, P=0.012) was an independent protective factor. The area under the curve calculated by the ROC curve was 0.619, the sensitivity was 0.742, and the specificity was 0.496 ( P=0.007), confirming the role of TCBI in the prognostic evaluation. Survival analysis showed that the median OS of patients in the TCBI high-value group was 42 months, and the 1-year and 3-year survival rates were 86.6% and 52.7%, significantly higher than those in the TCBI low-value group (20 months, 68.4% and 29.1% respectively; χ2=12.286, P<0.001). Subgroup analysis showed that among patients with radical radiotherapy, 3-year survival rate in patients with lower TCBI ( n=37) was lower than that in patients with higher values ( n=36) (21.6% vs. 44.4%, χ2=8.505, P=0.004). Conclusion:TCBI is a predictor of OS for middle-aged and elderly patients with thoracic ESCC who received radiotherapy. The lower the TCBI, the poorer the survival prognosis.
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Objective To explore the feasibility and safety of integrated intensity-modulated radiation therapy (IMRT) technology applied in craniospinal irradiation in a supine position. Methods The patients were fixed in a supine position using thermoplastic mask and vacuum mat. Three isocenters with a fixed interval of 20-25 cm were adopted according to the height of patients. A total of 13 beams with a length of 2-3 cm in the overlapping region were included in the treatment plan. Fixed jaw technique was employed and overall calculation was performed by the inverse optimization method. The γ-passing rate and absolute point dose verification were performed for three isocenters and two overlapping regions. Cone-beam CT (CBCT) images were scanned for three isocenters before treatment. The setup error of each isocenter in the x,y and z directions of the same coordinate system was recorded and overall analysis was conducted. Results Among 28 patients,the γ-passing rate (%) of three isocenters and two overlapping regions was 99. 36%, 99. 60%,99. 75%,94. 77% and 95. 09%,whereas the absolute point dose verification error was 1. 56%,-1. 56%,0. 52%,-0. 76% and -1. 68%,respectively. Twenty-eight patients received 162 groups of IGRT with 486 setup errors from the CBCT images. The average deviation in the x, y and z direction for three isocenters (neck,chest and abdomen) was 0. 17 mm,0. 10 mm,0. 02 mm,0. 06 mm,0. 04 mm,0. 46 mm, 0. 19 mm, 0. 26 mm and 0. 41 mm, respectively. Conclusions The integrated IMRT techniques for craniospinal irradiation in a supine position is feasible and safe,which is worthy of clinical application.
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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.
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Objective To evaluate the radiosensitization effect of low-temperature plasma on HepG2, A549, and HeLa cells.Methods Cells were divided into three groups, radiation group (R) , plasma treatment group(P), and plasma plus radiation group (P + R).After radiation, cell survival was detected by a cloning assay.Cell cycle distribution, apoptosis and ROS content were tested by flow cytometry.Western blot was used to measure the expressions of Caspase-3 and Bcl-2.Results Lowtemperature plasma showed radiosensitization effects on three different human malignant cell lines with a sensitivity enhancement ratio(SERD0) of 1.28,1.32 and 1.29.respectively.In these three different human malignant cell lines, compared with radiation alone group (R) , the G2/M arrest, apoptosis rate and ROS level in the group P + R were enhanced (the prolongation of G2/M arrest: t =9.52, 8.24, 9.53, P ＜ 0.05;the apoptosis rate: t =10.67, 38.56, 6.74, P ＜0.05;ROS content: t =9.41, 15.42, 13.53, P ＜0.05).In HepG2 cells and A549 cells, compared with group P, the prolongation of G2/M arrest, the apoptosis rate and ROS content of group P + R were enhanced (the prolongation of G2/M arrest: t =8.75, 20.37, P＜0.05;the apoptosis rate: t =8.43, 9.99, P ＜0.05;ROS content: t =4.82, 5.27, P ＜ 0.05).The expression level of Bcl-2 protein was downregulated in group P + R;by contrast, the expression level of Caspase-3 protein in group P + R was upregulated.Conclusions Low-temperature plasma can increase the radiosensitization of HepG2, A549 and HeLa cells with the enhancement of G2/M phase arrest, apoptosis induction and ROS generation.
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Three-dimensional cell culture is widely recognized as a model in vitro that can better simu-late the interaction between tumor cells in vivo and cell microenvironment. Compared with the traditional two-dimensional cell culture,it has obvious advantages in the study of the observation of tumor cells biological be-havior,tumor resistance,radiation insensitivity,gene expression in vivo and in other aspects of the study. It can provide a valuable model in vitro for experimental study on the basis of tumor.
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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.
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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.
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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.
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Objective To study investigate the dose accuracy that can be achieved with the method of bulk density assignment.Methods Sixteen cases of nasopharyngeal cancer patients and nineteen cases of esophageal cancer patients who accept radiotherapy in our department were selected.The planning CT images with bulk density assignment to different classes of tissues were applied to calculate the dose distributions,and then the resulting dose volume histograms (DVH) of the tumor and organs of risk were compared with the original treatment plan.The paired t-test was taken for dose comparison between two plans.Results The DVH comparison based on the planning CT and the bulk density assignment CT showed good agreements.With nasopharyngeal cancer patients,differences between the two plans about target and normal tissue were less than 1％.With esophageal cancer patients,the dose differences were less than 2％.Conclusion Preliminary results confirm that the bulk density assignment method can be applied to calculate the dose distributions.
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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.
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Objective To detect DNA damage of peripheral blood lymphocytes in patients and family members of autosomal dominant polycystic kidney disease (ADPKD),and to study the effect of irradiation on genomic stability of lymphocytes. Methods Before and after 0.5 Gy radiation dose,single-cell gel electrophoresis (SCGE) was employed to analyze DNA damage of lymphocytes in 10 ADPKD patients (group A),3 members without clinical symptoms of a ADPKD family (group B) and 20 healthy control people (group C).The damage was estimated based on the content of DNA in tail (TDNA％) with comet analysis software (CASP). Results Both before and after irradiation,the TDNA％ (8.85％±0.14％,14.84％±0.77％) and the value-added (6.00％±0.77％) of TDNA％ of group A were significantly higher than those of group C (7.50％±0.37％,12.46％±0.26％,4.96％±0.44％) respectively.There were no significant differences between group B and group C or group A and group B.While 1 person in group B had higher TDNA％ as compared to group C both before and after irradiation. Conclusions The lymphocytes of ADPKD patients are more sensitive to ionizing radiation as compared to healthy people.The genomic instability in ADPKD patients or member of ADPKD family may trigger cystic formation in multi-organs when exposing to environmental agents. SCGE may provide a new approach to elucidate the pathogenesis and prognosis of ADPKD.
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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.
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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.
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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.
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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.