Progress of research on the preventive and therapeutic agents against radiation-induced injuries / 中国辐射卫生

Radiation-induced injury, a body dysfunction caused by irradiation, is associated with the dose, duration, and speed of radiation and is predominantly derived from radiation therapy for patients with malignant tumors. The current clinical treatment mainly includes amelioration of injury, alleviation of symptoms, and improvements in function restoration of the affected sites because of lack of targeted agents specific to radiation-induced injuries. Research and development of preventive and therapeutic agents against radiation-induced injuries are of great significance to reduce the body damages caused by radiotherapy and improve the quality of life of cancer survivors. This review summarizes the radiation-induced injury and its mechanisms, radioprotectants, and therapeutic agents for radiation, and proposes future development directions, so as to provide a reference for alleviation of radiation-induced injury and improvement in prognosis.

Hydrogen therapy promotes macrophage polarization to the M2 subtype by inhibiting the NF-κB signaling pathway / 中国辐射卫生

Objective To investigate the role of hydrogen therapy in reducing radiation-induced lung injury and the specific mechanism. Methods Forty C57BL/6 mice were randomly divided into four groups: normal control group, model group, hydrogen therapy group I, and hydrogen therapy group II. A mouse model of radiation-induced lung injury was established. The pathological changes in the lung tissue of the mice were examined with HE staining. Immunofluorescence staining was used to detect the expression of surface markers of M1 and M2 macrophages to observe macrophage polarization. The expression of interleukin (IL)-6, tumor necrosis factor-α (TNF-α), and IL-10 in the lung tissue was measured by immunohistochemistry. The expression of nuclear factor-kappa B (NF-κB) p65 and phosphorylated NF-κB (P-NF-κB) p65 was measured by Western blot. Results HE staining showed that compared with the control group, the model group exhibited alveolar septal swelling and thickening, vascular dilatation and congestion, and inflammatory cell infiltration in the lung tissue; the hydrogen groups had significantly reduced pathological damage and inflammatory response than the model group, with more improvements in hydrogen group II than in hydrogen group I. Immunohistochemical results showed that compared with those in the control group, the levels of the inflammatory cytokines IL-6 and TNF-α were significantly increased in the model group; the hydrogen groups showed significantly decreased IL-6 and TNF-α levels and a significantly increased level of the anti-inflammatory factor IL-10 than the model group, which were more marked in hydrogen group II than in hydrogen group I. Immunofluorescence results showed that compared with the control group, the expression of the surface marker of M1 macrophages in the model group was significantly upregulated; the hydrogen groups showed significantly downregulated M1 marker and significantly upregulated M2 marker, and hydrogen group II showed significantly increased M2 marker compared with hydrogen group I. Western blot results showed that compared with that in the control group, the ratio of P-NF-κB p65/NF-κB p65 in the model group was significantly increased; the P-NF-κB p65/NF-κB p65 ratio was significantly reduced in the hydrogen groups than in the model group, and was significantly lower in hydrogen group II than in hydrogen group I. Conclusion Hydrogen inhalation therapy may reduce the inflammatory response of radiation-induced lung injury by inhibiting the NF-κB signaling pathway to promote the polarization of the macrophage M1 subtype to the M2 subtype.

BMSCs promote M2 macrophage polarization to attenuate acute radiation-induced lung injury / 中国辐射卫生

Objective To investigate the therapeutic effects of bone marrow mesenchymal stem cells (BMSCs) for radiation-induced lung injury (RILI) and the underlying mechanism. Methods Forty-five healthy adult male C57BL/6 mice were randomly divided into control, model, and BMSCs groups. The model and BMSCs groups received a single irradiation dose of 20 Gy to the chest, while the control group did not receive X-ray irradiation. For the BMSCs group, an injection of 1 × 106 BMSCs cells was administered via the tail vein within 6 h after irradiation. In the 5th week, the lung tissue was taken to observe pathological changes with HE staining; examine the expression of the inflammatory factors interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) with immunohistochemical staining; observe the polarization of macrophages with immunofluorescence staining; and measure the expression of the epithelial-mesenchymal transition markers E-cadherin, N-cadherin, and vimentin proteins by Western blot. Results After radiation, the model group developed pulmonary vasodilation and congestion with septal thickening and inflammatory cell infiltration, and these changes were markedly reduced in the BMSCs group. The model group showed significantly down-regulated expression of IL-6 and TNF-α compared with significantly increased levels in the model group (P < 0.01, P < 0.05). Treatment with BMSCs significantly increased the polarization of lung macrophages towards the M2 type, while significantly decreasing the abnormally increased N-cadherin and vimentin levels in RILI mice (P < 0.05, P < 0.01). Conclusion BMSCs have therapeutic effects for RILI mice, which may be through promoting macrophage polarization from M1 to M2.

Regulatory Mechanism of Radiation Therapy for Lung Cancer with Traditional Chinese Medicine： A Review / 中国实验方剂学杂志

Lung cancer is the fastest-growing cancer type in terms of incidence and mortality worldwide， posing a huge threat to the health and life of the population. Radiation therapy is one of the main methods for treating lung cancer， and there is a clear dose-effect relationship between the radiation dose and local control rate of lung cancer. However， the lung is a radiation dose-limiting organ， and the radiation resistance of lung cancer tissues and the radiation damage to normal tissues limit the radiation efficacy for lung cancer. The pathogenesis of lung cancer in traditional Chinese medicine （TCM） is characterized by an initial deficiency in vital Qi， followed by the internal invasion and gradual accumulation of pathogenic Qi. After radiation therapy for lung cancer， the body's vital Qi becomes weaker， and syndromes of phlegm coagulation， Qi stagnation， and static blood blocking collaterals become more severe， leading to radiation resistance of lung cancer tissues. Therefore， the key issue to better clinical efficacy of radiation therapy for lung cancer patients is to use drugs to enhance the radiation sensitivity of lung cancer cells and improve the radiation tolerance of normal lung tissues. TCM can be used as a radiation sensitizer by regulating the cell cycle to increase the proportion of cells in the radiation-sensitive phase， promoting upregulation of pro-apoptotic genes and downregulation of anti-apoptotic genes to induce cell apoptosis， enhancing DNA damage caused by radiation and inhibiting damage repair， improving blood circulation and tissue oxygen supply， and so on， to enhance the sensitivity of tumor cells to radiation and amplify the toxicity of radiation to tumor tissues. TCM can also be used as a radiation protector by inhibiting cell damage， regulating cytokines and immune balance， reducing the release of inflammatory and fibrotic factors， and inhibiting the activation of related signaling pathways to prevent and treat radiation-induced lung injury. This article systematically reviewed the research results of TCM on radiation sensitization and radiation protection in lung cancer in recent years， aiming to elucidate the mechanism of TCM in regulating the effect of radiation therapy for lung cancer and provide more theoretical and practical basis for TCM to participate in improving the prognosis of lung cancer patients undergoing radiation therapy.

Association between deacetylase Sirtuins and radiation-induced liver disease / 临床肝胆病杂志

Radiation-induced liver disease （RILD）， also known as radiation hepatitis， is subacute liver injury induced by radiation. As the focus of senescence-related studies， the deacetylase family Sirtuins （SIRTs） have the molecular functions including DNA repair and chromatin regulation， which makes SIRTs a hub for regulating genome and epigenome stability. Radiation-induced hepatic DNA damage and reaction is the primary physiological and pathological process of RILD， which is similar to the function of SIRTs. This article briefly introduces the structure and function of the SIRTs protein family， elaborates on the basic concepts and progress of the physical physiology of radiation therapy， discusses the internal relationship between SIRTs and RILD from the perspective of radiobiology， and points out the possibility of SIRTs as a target for the prevention and treatment of RILD.

Dry eye disease in head and neck cancer patients undergoing radiotherapy

Purpose: To study the incidence of dry eye disease (DED) in head and neck cancer (HNC) patients undergoing external beam radiotherapy (EBRT), to find a correlation between tumor location and total radiation dose with DED, and to report various radiotherapy (RT) induced acute toxic effects on ocular and adnexal structures. Methods: A prospective cohort study was conducted at a tertiary eye?care center on 90 patients of HNC undergoing EBRT from March 2021 to May 2022. All underwent a thorough clinical history and complete ophthalmological examination including an ocular surface disease index (OSDI) questionnaire, visual acuity, anterior segment, angle and posterior segment examination, dry eye workup including the Schirmer test, tear meniscus height, tear break?up time, corneal fluorescein staining and grading, and meibography by auto?refractometer and its scoring at each visit. Patients were evaluated before the start of RT and then at 1 week, 4 weeks, and 12 weeks post?RT. Radiation records of all patients were noted. Data were analyzed using percentage and Microsoft Excel. Results: Of the 90 patients, 66 were male and 24 female (M: F ratio of 2.75) with a median age of 52.5 years (range 24 to 80 years). The most common HNC was the carcinoma oral cavity and lip. Most patients received a total radiation dose between 46 to 55 Gy. DED developed in 48 (53.3%) patients. The incidence of DED increased with the increase in total radiation dose (r = 0.987). DED was also found to be correlated with tumor location (r = 0.983). Conclusion: The incidence of DED positively correlated with the total radiation dose and tumor location.

Oxidative stress and its correlation with nuclear factor-κB and transforming growth factor-β1 in liver injury induced by different doses of X-rays in mice / 环境与职业医学

Background Radiation-induced liver damage is a major complication for primary liver cancer and other upper abdominal tumors during radiation therapy. The early biological effects of radiation-induced liver damage at different doses of radiation and its mechanisms of action have not yet been elucidated. Objective To establish X-ray-induced radioactive mouse liver damage model and explore the level of oxidative stress and its correlation with nuclear factor-κB (NF-κB) and transforming growth factor-β1 (TGF-β1). Methods A total of 24 male C57BL/6J mice aged 6 weeks were randomly divided into 4 groups (control, 0.8 Gy, 1.6 Gy, and 4 Gy), with 6 mice in each group. X-rays irradiated the whole body of mice singly in each dose group. At 24 h after radiation, histopathological changes in mouse liver were evaluated; peripheral blood cell count, serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels, as well as liver tissue superoxide dismutase (SOD) activity, malondialdehyde (MDA) level, reduced glutathione (GSH) level, and 8-hydroxy-2′-deoxyguanosine (8-OHdG) level were measured; real-time fluorescence quantitative PCR was used to detect liver tissue NF-κB p65 and TGF-β1 mRNA expression levels; the correlations of oxidative stress indicators with NF-κB p65 and TGF-β1 mRNA expression levels were analyzed by Pearson correlation. Results Compared with the control group, at 24 h after different doses of X-ray radiation, early injury-related histopathological changes were observed in liver, and the serum levels of AST and ALT were significantly increased in the 4 Gy group (P<0.05); the numbers of peripheral blood leukocytes and lymphocytes were decreased in the radiation exposure groups (P<0.05), showing a decreasing trend with increasing radiation doses; the levels of liver oxidative stress indicators (MDA, SOD, and GSH) in exposed mice were significantly increased (P<0.05), showing an increasing trend with increasing radiation doses. The liver 8-OHdG were significantly increased in the 1.6 Gy and 4 Gy groups compared with the control and the 0.8 Gy groups, respectively (P<0.05). The NF-κB p65 and TGF-β1 mRNA expression levels in the liver of mice were significantly increased in the 1.6 Gy and 4 Gy groups compared with the control group (P<0.05). The TGF-β1 mRNA expression level also exhibited an increasing trend with increasing radiation doses. The results of correlation analysis showed that the levels of MDA, SOD, GSH, and 8-OHdG in liver tissues were significantly and positively correlated with the expression levels of NF-κB p65 and TGF-β1 mRNA (P<0.05). Conclusion X-rays of various doses can affect the degree of liver injury, peripheral blood cell count, serum levels of AST and ALT, and liver oxidative stress levels in mice. The level of oxidative stress induced by X-ray is positively correlated with NF-κB and TGF-β1 in liver tissues, and it may participate in the process of radiation-induced liver injury.

Establishment of a RILD model in C57BL/6J mice treated with precise radiotherapy / 中国辐射卫生

Objective To provide a reliable and stable animal model for investigating the molecular pathogenesis of radiation-induced liver disease (RILD). Methods Ninety C57BL/6J mice were divided into control, 20 Gy, 25 Gy, 30 Gy and 35 Gy radiation groups. The mice were executed at 4 weeks after radiation and the levels of alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase in the liver serum were measured. HE staining was performed on the pathological liver tissues. Masson staining was performed at 36 weeks after radiation. Results Compared with the control group, the fatality rate was higher in the 30 and 35 Gy radiation groups, and the body weight significantly decreased in the 20 and 25 Gy radiation groups. Compared with the control group, alanine aminotransferase significantly increased in mice exposed to 20 Gy, while aspartate aminotransferase and alanine aminotransferase increased in mice exposed to 25 Gy. No significant changes were observed in the livers of the mice in the 20 and 25 Gy radiation groups, but pathological examination showed liver damage induced by both 20 and 25 Gy radiation. Conclusion A stable and reliable mouse model of RILD was constructed for treatment with linear accelerator. The mouse model of RILD constructed for stereotactic body radiation therapy using linear accelerator has significant research implications for the exploration of RILD.

Role of cell fate regulation by ionizing radiation in radiation-induced lung injury and its therapeutic progress / 西安交通大学学报(医学版)

Radiation induced lung injury (RILI) is a common complication after radiation therapy of breast tumors and bone marrow transplantation pretreatment, and it is a critical limiting factor of radiotherapy doses in patients. Once RILI progresses to the radiation-induced pulmonary fibrosis stage, it seriously reduces the patient’s quality of life, while causing the patient’s respiratory failure and eventually leading to death. Ionizing radiation (IR) can induce cell injuries, including apoptosis, epithelial-mesenchymal transition, senescence, pyroptosis and ferroptosis, and these injuries can play an important role in the occurrence and development of radioactive lung injury. Starting from discussion of the occurrence of different forms of injury in different cells after IR stimulation, this review summarizes the pathogenesis of RILI and its clinical prevention and treatment.

Evaluation of the therapeutic effect of deuterium depleted water on gastroenteritis induced by 131I radiation in thyroid cancer treatment / 中国辐射卫生

Objective To investigate the therapeutic effect of oral administration of deuterium depleted water on gastroenteritis induced by 131I radiation in thyroid cancer treatment. Methods Fifty patients with papillary thyroid cancer treated with 131I in the Department of Nuclear Medicine of Changshu No.2 People’s Hospital from May 2022 to February 2023 were divided into control group and experimental group (25 patients in each group). Data were continuously collected throughout the study duration. The control group was orally administrated omeprazole enteric-coated capsules and purified water at 660 mL tid for 5 days. The experimental group received the same basic treatment as the control group except that deuterium depleted water was used instead of purified water. The incidence and alleviation of 131I radiation-induced gastroenteritis were observed and compared between the two groups using the Fisher’s exact test and Kaplan-Meier analysis. Results The number of gastroenteritis cases from day 1 to day 5 after 131I administration was 2 (8%), 5 (20%), 2 (8%), 1 (4%), and 0 (0%), respectively, in the experimental group, and 2 (8%), 8 (32%), 4 (16%), 3 (12%), and 1 (4%), respectively, in the control group. The incidence of gastroenteritis was significantly different between the two groups (χ2=4.064, P=0.044). After 5 days of treatment, the overall response rate of patients in the experimental group was 96%, which was significantly higher than 76% in the control group (χ2=9.105, P=0.025). Conclusion Oral administration of deuterium depleted water is effective in the relief of clinical symptoms of 131I radiation-induced gastroenteritis in thyroid cancer treatment. The clinical application of deuterium depleted water should be further investigated.

Protective effect and mechanism of mesenchymal stem cell-derived extracellular vesicle on radiation-induced liver injury / 器官移植

Objective To evaluate the protective effect and the underlying mechanism of mesenchymal stem cell-derived extracellular vesicle (MSC-EV) on radiation-induced liver injury and liver cell line injury in mouse models. Methods C57BL/6 mice were randomly divided into the blank group, model group and MSC-EV treatment group (treatment group), with 9 mice in each group. AML12 cells were randomly divided into the control group, irradiation group and MSC-EV intervention group (intervention group). Animal and cell models with radiation-induced injury were established by one-time 15 Gy and 6 Gy X-ray irradiation, respectively. At 48 h after irradiation, liver tissues and serum samples of mice were collected and prepared for subsequent experiments. At 15 h post-irradiation, cell experiment was carried out. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and content of malondialdehyde (MDA) in liver tissues and cells were measured. The relative expression levels of interleukin (IL)-1β, IL-6, transforming growth factor (TGF)-β and CXC chemokine ligand (CXCL)10 messenger RNA (mRNA) were detected by real-time fluorescent quantitative polymerase chain reaction (RT-qPCR). Liver tissues were prepared for hematoxylin-eosin (HE) staining to calculate liver pathological injury score. The apoptosis of liver tissues and cells was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) and propidiumiodide (PI) staining, respectively. The expression levels of glutathione peroxidase 4 (GPX4) and ferroptosis suppressor protein 1 (FSP1) proteins were detected by Western blot. The production level of reactive oxygen species (ROS) was detected by dihydroethidine (DHE) staining. The fluorescence intensity of mitochondrial permeability transition pore (mPTP) was determined. Results Compared with the blank group, serum levels of AST and ALT were up-regulated, and the relative expression levels of IL-1β, TGF-β and CXCL10 mRNA in the mouse liver tissues were up-regulated, and MDA content was increased, liver injury score was elevated, cell apoptosis rate was increased, intracellular ROS level was elevated, and the relative expression levels of GPX4 and FSP1 proteins in the mouse liver tissues were down-regulated in the model group, and the differences were statistically significant (all P<0.05). Compared with the model group, serum levels of AST and ALT were decreased, and the relative expression levels of IL-1β, TGF-β and CXCL10 mRNA in the liver tissues of mice were down-regulated, MDA content was declined, liver injury score was declined, cell apoptosis rate was decreased, intracellular ROS level was decreased, and the relative expression levels of GPX4 and FSP1 proteins in the liver tissues of mice were up-regulated in the treatment group, and the differences were statistically significant (all P<0.05). Compared with the control group, cell apoptosis rate was increased, intracellular ROS level was elevated, the fluorescence intensity of mPTP was weakened, the relative expression levels of IL-1β, TGF-β and IL-6 mRNA were up-regulated, MDA content was increased, and the relative expression levels of GPX4 and FSP1 proteins were down-regulated in the irradiation group, and the differences were statistically significant (all P<0.05). Compared with the irradiation group, cell apoptosis rate was declined, intracellular ROS level was decreased, the fluorescence intensity of mPTP was strengthened, the relative expression levels of IL-1β, TGF-β and IL-6 mRNA were down-regulated, MDA content was decreased and the relative expression levels of GPX4 and FSP1 proteins were up-regulated in the intervention group, and the differences were statistically significant (all P<0.05). Conclusions MSC-EV may effectively alleviate radiation-induced liver injury by reducing ferroptosis of liver cells, enhancing antioxidant level and decreasing the production of lipid peroxide, thereby effectively alleviating radiation-induced liver injury.

Discovery of the radio-protecting effect of Ecliptae Herba, its constituents and targeting p53-mediated apoptosis in vitro and in vivo

Radiation protection drugs are often accompanied by toxicity, even amifostine, which has been the dominant radio-protecting drug for nearly 30 years. Furthermore, there is no therapeutic drug for radiation-induced intestinal injury (RIII). This paper intends to find a safe and effective radio-protecting ingredient from natural sources. The radio-protecting effect of Ecliptae Herba (EHE) was discovered preliminarily by antioxidant experiments and the mouse survival rate after 137Cs irradiation. EHE components and blood substances in vivo were identified through UPLC‒Q-TOF. The correlation network of "natural components in EHE-constituents migrating to blood-targets-pathways" was established to predict the active components and pathways. The binding force between potential active components and targets was studied by molecular docking, and the mechanism was further analyzed by Western blotting, cellular thermal shift assay (CETSA), and ChIP. Additionally, the expression levels of Lgr5, Axin2, Ki67, lysozyme, caspase-3, caspase-8,8-OHdG, and p53 in the small intestine of mice were detected. It was found for the first time that EHE is active in radiation protection and that luteolin is the material basis of this protection. Luteolin is a promising candidate for RⅢ. Luteolin can inhibit the p53 signaling pathway and regulate the BAX/BCL2 ratio in the process of apoptosis. Luteolin could also regulate the expression of multitarget proteins related to the same cell cycle.

Research progress in prevention and treatment of radiation-induced intestinal injury by traditional Chinese medicine active components / 中国中药杂志

Radiation-induced intestinal injury(RIII), a common complication of radiotherapy for pelvic malignancies, affects the quality of life and the radiotherapy efficacy for cancer. Currently, the main clinical approaches for the prevention and treatment of RIII include drug therapy, hyperbaric oxygen therapy, and surgical treatment. Among these methods, drug therapy is cost-effective. Traditional Chinese medicine(TCM) containing a variety of active components demonstrates mild side effects and good efficacy in preventing and treating RIII. Studies have proven that TCM active components, such as flavonoids, terpenoids, phenylpropanoids, and alkaloids, can protect the intestine against RIII by inhibiting oxidative stress, regulating the expression of inflammatory cytokines, modulating the mitochondrial apoptosis pathway, adjusting intestinal flora, and suppressing cell apoptosis. These mechanisms can help alleviate the symptoms of RIII. The paper aims to provide a theoretical reference for the discovery of new drugs for the prevention and treatment of RIII by reviewing the literature on TCM active components in the last 10 years.

Types and Incidence of Moderate and Severe Toxic Effects of Carbon Ion Radiotherapy for Head and Neck Cancer / 肿瘤防治研究

Head and neck tumors often have complex anatomical structures and are adjacent to important organs. Radiation injury caused by conventional radiotherapy technology is the main dose-limiting factor. Carbon ion beam has become the most ideal radiation to replace photon due to its excellent relative biological effect and Bragg peak. By 2019, 32 000 people worldwide have received carbon ion radiotherapy (CIRT). Despite the efficient tumor killing ability of this technology, radiation injury cannot be avoided. This article reviews the types and incidence of moderate to severe radiation injury caused by CIRT in head and neck cancer to provide a comprehensive understanding of the potential risks in CIRT.

Analysis of risk factors of radiation-induced toxicity in limited-stage small cell lung cancer treated with hypofractionated intensity-modulated radiotherapy / 中华肿瘤杂志

Objective: To compare the incidence of radiation-related toxicities between conventional and hypofractionated intensity-modulated radiation therapy (IMRT) for limited-stage small cell lung cancer (SCLC), and to explore the risk factors of hypofractionated radiotherapy-induced toxicities. Methods: Data were retrospectively collected from consecutive limited-stage SCLC patients treated with definitive concurrent chemoradiotherapy in Cancer Hospital of Chinese Academy of Medical Sciences from March 2016 to April 2022. The enrolled patients were divided into two groups according to radiation fractionated regimens. Common Terminology Criteria for Adverse Events (CTCAE, version 5.0) was used to evaluate the grade of radiation esophagus injuries and lung injuries. Logistic regression analyses were used to identify factors associated with radiation-related toxicities in the hypofractionated radiotherapy group. Results: Among 211 enrolled patients, 108 cases underwent conventional IMRT and 103 patients received hypofractionated IMRT. The cumulative incidences of acute esophagitis grade ≥2 [38.9% (42/108) vs 35.0% (36/103), P=0.895] and grade ≥ 3 [1.9% (2/108) vs 5.8% (6/103), P=0.132] were similar between conventional and hypofractionated IMRT group. Late esophagus injuries grade ≥2 occurred in one patient in either group. No differences in the cumulative incidence of acute pneumonitis grade ≥2[12.0% (13/108) vs 5.8% (6/103), P=0.172] and late lung injuries grade ≥2[5.6% (6/108) vs 10.7% (11/103), P=0.277] were observed. There was no grade ≥3 lung injuries occurred in either group. Using multiple regression analysis, mean esophageal dose ≥13 Gy (OR=3.33, 95% CI: 1.23-9.01, P=0.018) and the overlapping volume between planning target volume (PTV) and esophageal ≥8 cm(3)(OR=3.99, 95% CI: 1.24-12.79, P=0.020) were identified as the independent risk factors associated with acute esophagitis grade ≥2 in the hypofractionated radiotherapy group. Acute pneumonitis grade ≥2 was correlated with presence of chronic obstructive pulmonary disease (COPD, P=0.025). Late lung injuries grade ≥2 was correlated with tumor location(P=0.036). Conclusions: Hypofractionated IMRT are tolerated with manageable toxicities for limited-stage SCLC patients treated with IMRT. Mean esophageal dose and the overlapping volume between PTV and esophageal are independently predictive factors of acute esophagitis grade ≥2, and COPD and tumor location are valuable factors of lung injuries for limited-stage SCLC patients receiving hyofractionated radiotherapy. Prospective studies are needed to confirm these results.

Research Progress of Radiation-induced Brain Injury for Nasopharyngeal Carcinoma / 肿瘤防治研究

Radiation-induced brain injury (RBI) is a common long-term complication of radiotherapy for nasopharyngeal carcinoma (NPC) and seriously affects the quality of life and overall survival of patients. In the era of intensity-modulated radiation therapy (IMRT), the long-term complications after radiotherapy, especially RBI, are becoming increasingly concerning because a number of treated patients with NPC obtain long-term survival. At present, the understanding of RBI is still being explored, and its pathogenesis and treatment methods are continuously updated. This article reviews the research progress of RBI in patients with NPC.

Role of Cytokines and Related Signaling Pathways in Intervention of Chinese Medicine in Radiation-induced Lung Injury： A Review / 中国实验方剂学杂志

Radiation-induced lung injury （RILI）， one of the common complications caused by radiotherapy， encompasses two phases： an early phase known as radiation pneumonitis （RP） and a late phase called radiation fibrosis （RF）， threatening the life and life quality of patients， with poor prognosis. Accumulating evidence has shown that the occurrence of RILI is related to a variety of cytokines and signaling pathways. This paper summarized the research on the effects of Chinese medicine on RILI from the perspective of cytokines and signaling pathways. Cytokines include transforming growth factor-β1 （TGF-β1）， interleukins （ILs）， tumor necrosis factor-α （TNF-α）， platelet-derived growth factor （PDGF）， vascular endothelial growth factor （VEGF）， and high mobility group box-1 （HMGB1）. Related signaling pathways are phosphatidylinositol-3-kinase/protein kinase B（PI3K/Akt） signaling pathway， mitogen-activated protein kinase （MAPK） signaling pathway， Wnt/β-catenin signaling pathway， Notch1/Jagged1 signaling pathway， and nuclear factor-E2-related factor2/antioxidant response element （Nrf2/ARE） signaling pathway. Cytokines may interfere with RILI progression by initiating various downstream signaling pathways， such as TGF-β1/Smads signaling pathway， TGF-β1/VEGF signaling pathway， TNF-α/nuclear factor-κB （NF-κB） signaling pathway， and HMGB1/Toll-like receptor 4 （TLR4） signaling pathway. In recent years， many scholars have attempted to delay RILI progression by down-regulating the expression of cytokines， antagonizing the effect of cytokines or regulating signaling pathways. It has been verified that many Chinese medicines， Chinese medicine monomers， and compound Chinese medicine prescriptions can inhibit the release of some cytokines or regulate some signaling pathways to reduce the incidence/severity of RILI， with satisfactory therapeutic effects， which have attracted the interest of scholars.

Resveratrol up regulates the expression of SIRT1 and mediates protective effect on radiation-induced myocardial injury / 中华放射肿瘤学杂志

Objective:To evaluate the effect of resveratrol on radiation-induced myocardial injury in mice.Methods:A total of 80 C57BL/6 mice were randomly divided into the control group, resveratrol (Res) group, radiation (RT) group and radiation+resveratrol (RT+Res) group. In the RT group, mice were given with heart radiation and mice in the Res group were given with resveratrol by gavage for 3 months. Cardiac ultrasound was used to evaluate cardiac function at 3 months after cardiac radiation. The hearts of mice were collected for HE staining, immunofluorescence, TUNEL staining, Masson staining and Western blot to evaluate the expression of silent information regulator 1 (SIRT1), the level of oxidative stress, inflammatory response, apoptosis and the degree of fibrosis in myocardial tissues. Experimental data were expressed as Mean ± SD. Continous data were statistically analyzed by t-test. Results:After 3 months of irradiation, compared with the control group, the ejection fraction (EF) and fractional shortening (FS) of cardiac function were decreased, and myocardial degeneration and disorder, reactive oxygen species (ROS) and inflammatory levels (interleukin-1β, interleukin-6, tumor necrosis factor-α), myocardial apoptosis (TUNEL positive cell rate) and fibrosis were increased in the RT group. In the RT+Res group, the cardiac function was improved, the expression of SIRT1 was increased, and the levels of oxidative stress, inflammation, myocardial apoptosis and fibrosis were decreased.Conclusions:Resveratrol can reduce oxidative stress, inflammatory infiltration, apoptosis and fibrosis of myocardium in mice with radiation-induced myocardial injury, thereby improving cardiac structural abnormalities and cardiac dysfunction. This protective effect can be mediated by upregulation of SIRT1 expression.

Treatment and prevention of acute radiation-induced vaginal injury in cervical cancer / 中华放射肿瘤学杂志

Concurrent chemoradiotherapy is the main treatment for locally advanced cervical cancer, and the incidence of vaginal injury is inevitable after radiotherapy. However, insufficient attention has been paid to the treatment and prevention of acute radiation-induced vaginal injury. Therefore, the mechanism, treatment and prevention of acute vaginal side effects after radiotherapy in cervical cancer were reviewed in this article, aiming to reduce the incidence of vaginal injury, complete the course of radiotherapy and improve the quality of life.

Mechanisms of copper transporter 1 gene in regulating radiation induced intestinal injury / 中华放射医学与防护杂志

Objective:To investigate the effects and mechanisms of copper transporter 1 (CTR1) in radiation induced intestinal injury in vitro. Methods:Human small intestinal epithelial cells (HIEC) were irradiated with 2, 4, 6, 8 Gy of X-rays and rat intestinal epithelial cells (IEC-6) were irradiated with 5, 10, 15, 20 Gy of X-rays. At 2, 4, 8, 24, and 48 h after irradiation, the expression of CTR1 was detected by Western blot assay. In some experiments, HIEC and IEC-6 cells were transfected with CTR1 shRNA and then exposed to X-rays. Copper levels were detected by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The radiosensitivity of cells was verified by colonogenic assay, the cellular reactive oxygen species (ROS) level and DNA damage were detected to further explore the related mechanism. In addition, Western blot was applied to detect the expressions of antioxidants and cuproptosis associated proteins in enterocytes after silencing CTR1 or irradiation.Results:The expression of CTR1 was increased by X-ray irradiation in a dose-dependent manner ( t=3.53, 3.45, 6.37, 11.11, 11.13, P<0.05). CTR1 expression was successfully diminished by CTR1 shRNA adenovirus vectors. According to the survival curves, the enhancement ratios of the radiosensitivity of HIEC and IEC-6 cells with CTR1 knocking-down were 1.146 and 1.201, respectively. Radiation-induced copper accumulation was alleviated after CTR1 silencing in IEC-6 cells ( t=3.10, P<0.05). At 0.5 h after irradiation, the ROS production in the CTR1 knockdown group was significantly lower than that in the control group ( t=5.23, 2.96, P<0.05). At 1 h after irradiation, the protein expression of γ-H2AX in the CTR1 knockdown group was obviously lower than that in the control group ( t=7.50, 4.29, P<0.05). The expressions of Nrf2 and HO-1 were increased after irradiation, which could be further increased after CTR1 silencing. In addition, cuproptosis associated protein DLAT, LIAS and FDX1 were reduced post-irradiation, which were recovered after CTR1 silencing. Conclusions:The radioresistance of HIEC and IEC-6 cells was enhanced after CTR1 silencing, possibly through the intracellular ROS and cuproptosis pathway.