OBJECTIVETo assess the effects of tumor necrosis factor-α (TNF-α) in enhancing the radiosensitivity of lung cancer cells in vitro.

METHODSA549 cells were exposed to γ-ray with or without TNF-α treatment. MTT assay was used to evaluate the cell viability, and flow cytometry was performed to assess the cell apoptosis. Western blotting was used to observe the expression of caspase-3 protein in the exposed cells.

RESULTSCompared with the exposed cells without TNF-α treatment, the cells treated with TNF-α showed significantly suppressed cell proliferation, increased the cell apoptosis, altered cell cycle, and increased caspase-3 protein expression after γ-ray exposure.

CONCLUSIONTNF-α can enhance the radiosensitivity of A549 cells to increase the efficiency of radiotherapy with γ-ray irradiation.

Apoptosis ; drug effects ; radiation effects ; Cell Cycle ; drug effects ; radiation effects ; Cell Line, Tumor ; Gamma Rays ; Humans ; Lung Neoplasms ; Radiation Tolerance ; drug effects ; Tumor Necrosis Factor-alpha ; pharmacology

AIMTo study effect of soybean isoflavones (SI) on spleen in radiated mice.

METHODS90 male mice were randomly divided into control group, radiated group, radiated plus 0.5% dose SI group. After 2-week feeding, the mice received 4.0 Gy 137Cs gamma-radiation, the cell cycles, cell apoptosis and proliferation on the spleen and the spleen index were observed in radiated after 12 h, 24 h, 1 week and 2 weeks.

RESULTSAfter the mice were radiated, the spleen were significantly atrophy, the rate of the cell apoptosis and the cell cycles of G0-G1 phase in splenocytes were significantly increased (P < 0.01), the cell cycles rate of S phase and the proliferation index were significantly decreased in spleen (P < 0.05). Compared with radiated group, the spleen atrophy and the rate of the cell cycles of G0-G1 phase were significantly decreased (P < 0.05), and the cell cycles of G2-M phase and the proliferation index were significantly increased (P < 0.05) in the mice supplied 0.5% soybean isoflavones.

CONCLUSIONThe soybean isoflavones could significantly increase spleen radioprotective effect in mice.

Animals ; Apoptosis ; drug effects ; radiation effects ; Cell Cycle ; drug effects ; radiation effects ; Cellular Structures ; Isoflavones ; pharmacology ; Male ; Mice ; Mice, Inbred Strains ; Radiation, Ionizing ; Soybeans ; Spleen ; cytology

OBJECTIVETo explore the effect of NAD+ against radiation injury and its dose-effect relationship.

METHODSL02 liver cells cultured in RPMI 1640 medium containing 10% fetal calf serum were exposed to X-ray irradiation followed by immediate application of NAD+. The cellular viability was analyzed by MTT assay and the apoptotic cells were detected by TUNEL methods to observe the damages of L02 liver cells induced by X-ray exposure and analyze the dose-effect relationship of NAD+.

RESULTSThe viability of L02 liver cells was decreased with increasing dose of X-ray irradiation. The most obvious growth inhibition of L02 cells occurred 24 h after the irradiation. NAD+ significantly increased the cell survival rate after irradiation, and this effect was gradually increased within the concentration range of 100-1000 microg/ml; at higher concentrations, the survival rate of the irradiated L02 cells showed no significant increase.

CONCLUSIONNAD+ provides partial protection of the liver cells against radiation injury, and the effect is positively correlated to NAD+ concentration within a certain range.

Apoptosis ; drug effects ; radiation effects ; Cell Line ; Cell Survival ; drug effects ; radiation effects ; Dose-Response Relationship, Drug ; Hepatocytes ; cytology ; drug effects ; radiation effects ; Humans ; NAD ; administration & dosage ; pharmacology ; Radiation Injuries ; prevention & control

OBJECTIVETo observe the effect of Liuweidihuang Pills in relieving cellphone electromagnetic radiation-induced histomorphological abnormality, oxidative injury, and cell apoptosis in the rat testis.

METHODSThirty adult male SD rats were equally randomized into a normal, a radiated, and a Liuweidihuang group, the animals in the latter two groups exposed to electromagnetic radiation of 900 MHz cellphone frequency 4 hours a day for 18 days. Meanwhile, the rats in the Liuweidihuang group were treated with the suspension of Liuweidihuang Pills at 1 ml/100 g body weight and the other rats intragastrically with the equal volume of purified water. Then all the rats were killed for observation of testicular histomorphology by routine HE staining, measurement of testicular malondialdehyde (MDA) and glutathione (GSH) levels by colorimetry, and determination of the expressions of bax and bcl-2 proteins in the testis tissue by immunohistochemistry.

RESULTSCompared with the normal controls, the radiated rats showed obviously loose structure, reduced layers of spermatocytes, and cavitation in the seminiferous tubules. Significant increases were observed in the MDA level (P < 0.01) and bax expression (P < 0.01) but decreases in the GSH level (P < 0.01) and bcl-2 expression (P < 0.01) in the testis issue of the radiated rats. In comparison with the radiated rats, those of the Liuweidihuang group exhibited nearly normal testicular structure, significantly lower MDA level (P < 0.05), bax expression (P < 0.01), and bcl-2 expression (P < 0.01).

CONCLUSIONLiuweidihuang Pills can improve cellphone electromagnetic radiation-induced histomorphological abnormality of the testis tissue and reduce its oxidative damage and cell apoptosis.

Animals ; Apoptosis ; drug effects ; radiation effects ; Body Weight ; drug effects ; radiation effects ; Cell Phone ; Drugs, Chinese Herbal ; pharmacology ; Electromagnetic Radiation ; Glutathione ; metabolism ; Male ; Malondialdehyde ; metabolism ; Oxidative Stress ; Radiation-Protective Agents ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Seminiferous Tubules ; drug effects ; radiation effects ; Spermatocytes ; drug effects ; metabolism ; radiation effects ; Staining and Labeling ; Testis ; drug effects ; metabolism ; pathology ; radiation effects

OBJECTIVETo explore the effects of Huqi Extractum (HQE) on the viability and apoptosis in mouse thymic lymphocytes against 60Co radiation.

METHODSThymic lymphocytes were isolated from 4 -8 weeks healthy male Kunming mice and primarily cultured. Then they were divided into the control group, the irradiation group, the low dose HQE group, the medium dose HQE group, and the high dose HQE group. Equal volume of serum free RPMI-1640 culture solution was added in the control group and the irradiation group, while equal volume of HQE solution (at the daily dose of 25, 50, and 100 mg/mL) was respectively added in the low, medium, and high dose HQE groups. Except the control group, those in the rest groups were exposed radiation at a single dose of 5 Gy gamma-ray. Changes of the thymic lymphocytes' viability were measured by MTT colorimetric assay at 12, 24, 36, and 48 h after radiation. The early apoptosis rate was detected using flow cytometry (FCM) after 10-h radiation. The apoptosis was detected using agarose gel electrophoresis to observe the DNA injury after 24-h radiation.

RESULTSThe viability level decreased more obviously in the irradiation group than in the control group at 24 -48 h after radiation (P < 0.01, P < 0.05). The average viability level was obviously higher in the low, medium, and high dose HQE groups than in the irradiation group (P < 0.05) in a dose dependent manner. The early apoptosis rate was obviously lower in the low, medium, and high dose HQE groups than in the irradiation group, with statistical difference shown in the high dose HQE group (P < 0.01). Typical DNA ladder fragments were found in the electrophoresis in all groups except the control group. But the DNA injury was comparatively milder in the low, medium, and high dose HQE groups, with more obvious effects shown in the high dose HQE group.

CONCLUSIONHQE showed protection for the viability of early thymic lymphocytes exposed to the 60CO radiation, and could lower the early apoptosis level.

Animals ; Apoptosis ; drug effects ; radiation effects ; Cell Survival ; drug effects ; radiation effects ; Cells, Cultured ; Drugs, Chinese Herbal ; pharmacology ; Gamma Rays ; adverse effects ; Male ; Mice ; Mice, Inbred Strains ; Thymocytes ; drug effects ; radiation effects

OBJECTIVETo study radiation-enhancing effects on human gastric cancer MKN28 cell line and underlying mechanisms of β-elemene.

METHODSInhibition of MKN28 cell proliferation at different concentrations of β-elemene was assessed using the methyl thiazolyl blue colorimetric method (MTT method), with calculation of IC50 value and choice of 20% of the IC50 as the experimental drug concentration. Irradiation group and β-elemene+irradiation group were established, and the cell survival fraction (SF) was calculated from flat panel colony forming analysis, and fitted by the 'multitarget click mathematical model'. Draw the survival curve and get the radiobiological parameters D0, Dq, SF2, N and SER. Flow cytometry (FCM) was used to detect changes in the cell cycle and cell apoptosis rates was detected by Annexin-V/PI assay.

RESULTSβ-elemene exerted inhibitory effects on proliferation of gastric cancer MKN28 cells, with an IC50 of 45.6 mg/L and we chose 8 mg/L as the experimental concentration. The cell survival fraction of MKN28 cells with irradiation decreased significantly after treated with β-elemene; D0, Dq decreased, SER = 1.3. After combined treatment of β-elemene+irradiation, the results of FCM showed that cells could be arrested in the G2/M phase and the cell apoptosis increased significantly.

CONCLUSIONSβ-elemene can enhance the radiosensitivity of gastric cancer MKN28 cell line. Mechanistically, β-elemene mainly influences the cell cycle distribution of MKN28 cells by inducing G2/M phase arrest, inhibits the repair of sublethal damage and induces cell apoptosis to enhance the killing effects of radioactive rays.

Apoptosis ; drug effects ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cell Survival ; drug effects ; Humans ; Radiation Tolerance ; drug effects ; Sesquiterpenes ; pharmacology ; Stomach Neoplasms ; pathology

OBJECTIVETo investigate the effects of the ultra-filtration extract mixture from Hedysarum Polybotrys (UEMHP) on the radiosensitivity of HepG2 cells, and to explore its possible mechanisms.

METHODSThe proliferation inhibition effects of UEMHP on HepG2 cells was detected by CCK-8 assay. The colony formation assay was used for the survival fraction (SF) analysis. The distribution of the cell cycle and the apoptosis rate were detected using flow cytometry (FCM). The survivin mRNA expression level was detected using reverse transcription-PCR assay.

RESULTSThe inhibition of UEMHP on HepG2 cells was time-and dose-dependent at the concentration ranging between 5 -50 mg/L (P < 0.05). The parameters of the two curve for SF (P < 0.05) showed statistical difference between the irradiation group and the UEMHP irradiation group. UEMHP could inhibit the clone formation of HepG2 cells and enhance the radiosensitivity of HepG2 cells. The results of FCM showed that UEMHP could induce G2/M phase arrest. The apoptosis rate in the UEMHP irradiation group (21.42% +/- 3.74%) was higher than that in the control group (5.35% +/- 0.41%), the only UEMHP group (10.36% +/- 1.75%), or the irradiation group (10.58% +/- 2.01%) (P < 0.01). RT-PCR showed that the survivin mRNA expression level was lower in the UEMHP irradiation group (0.31 +/- 0.02) than in the control group (0.82 +/- 0.06) and the irradiation group (0.58 +/- 0.04) respectively, showing statistical difference (P < 0.01).

CONCLUSIONUEMHP can enhance the radiosensitivity of HepG2 cells, and its possible mechanisms might be correlated to down-regulating the survivin mRNA expression and promoting the apoptosis.

Apoptosis ; Cell Proliferation ; drug effects ; radiation effects ; Drugs, Chinese Herbal ; pharmacology ; Hep G2 Cells ; Humans ; Inhibitor of Apoptosis Proteins ; metabolism ; Radiation Tolerance ; drug effects

Radiotherapy, frequently used for treatment of solid tumors, carries two main obstacles including acquired radioresistance in cancer cells during radiotherapy and normal tissue injury. Phenylpropanoids, which are naturally occurring phytochemicals found in plants, have been identified as potential radiotherapeutic agents due to their anti-cancer activity and relatively safe levels of cytotoxicity. Various studies have proposed that these compounds could not only sensitize cancer cells to radiation resulting in inhibition of growth and cell death but also protect normal cells against radiation-induced damage. This review is intended to provide an overview of recent investigations on the usage of phenylpropanoids in combination with radiotherapy in cancer treatment.
Antineoplastic Agents/*therapeutic use ; Apoptosis/drug effects/radiation effects ; Chromones/therapeutic use ; Combined Modality Therapy ; Cytoprotection/drug effects/radiation effects ; Humans ; Neoplasms/pathology/*radiotherapy ; Phenylpropionates/therapeutic use ; Plants ; Radiation Tolerance/drug effects ; Radiation-Sensitizing Agents/*therapeutic use ; *Radiotherapy

UV radiation is known to cause photoaging of the skin and is considered one of the leading cause of developing skin carcinogenesis. Melatonin which has a highly lipophilic molecular structure facilitating penetration of cell membranes and serving as an extra- and intracellular free radical scavenger has been demonstrated to protect photodamage of skin affected by UV exposure. In this study, we have examined the role of melatonin in response to UVB induced photodamaging process, using human skin fibroblasts in vitro. Cell survival curves after UVB irradiation showed dose-dependent decrease. Only 60% of fibroblasts were survived at 140 mJ/cm2 UVB irradiation. By pre-cultivation of cells with melatonin (100 nM), a significant number of cells remained unaffected. After UVB irradiation with 70 mJ/cm2, the level of putrescine was 1.7+/-0.3 fold increased compared to melatonin pre-treated group. In Northern analyses, the transcriptional level of ornithine decarboxylase (ODC) gene expression was increased by UVB irradiation and prohibited by melatonin. These results indicated that melatonin was effectively able to neutralize membrane peroxidation when present in relevant concentration during UVB irradiation and diminishes the UVB-induced increase of polyamine synthesis and ODC gene expression. Collectively, ODC response to UVB induced changes are possibly involves a melatonin or antioxidant sensitive regulatory pathway in normal human skin fibroblast.
Antioxidants/*pharmacology ; Apoptosis/drug effects/radiation effects ; Fibroblasts/*drug effects/*radiation effects ; Human ; Melatonin/*pharmacology ; Ornithine Decarboxylase/biosynthesis/genetics ; Polyamines/*metabolism ; *Ultraviolet Rays

OBJECTIVETo study effects of hypericin associated with light irradiation on human laryngeal squamous cell carcinoma strain Hep-2.

METHODSUsing techniques of tumor cells culture in vitro, Hep-2 cells were exposed to different concentration hypericin as 0.5, 1.0, 2.0, 3.0, 5.0 microg/ml, then 10 minutes 7.5 J/cm2 light irradiation was given after an hour. Other groups Hep-2 culture cells were also exposed to different concentration hypericin as 5.0, 10.0, 20.0, 25.0 microg/ml, without light irradiation. In all groups, contrast groups were set up. And 48 hours later, growth characteristics of Hep-2 cells were studied by morphological observation, fluorescence microscope, MTT assay and flow cytometry.

RESULTSIn normal contrast group, Hep-2 cells grew intensively and contacted with each other. However, cells which were treated with hypericin, combination with light irradiation were declined greatly. In higher dose hypericin group, necrosis could be found. MTT assay showed that hypericin associated with light irradiation inhibited growth of laryngeal cell with dose dependence manner. Flow cytometry showed that hypericin with light irradiation could block cell growth at G0/G1 phase, inducing apoptosis of laryngeal cell. Under fluorescence microscope, some sings of cell apoptosis including coagulation of chromatin, fragmentation of nuclei and apoptotic body could be found.

CONCLUSIONHuman laryngeal squamous cell carcinoma strain Hep-2 can be inhibited and induced into apoptosis by treated with hypericin combination with light irradiation.

Apoptosis ; drug effects ; radiation effects ; Carcinoma, Squamous Cell ; pathology ; Cell Proliferation ; drug effects ; radiation effects ; Hep G2 Cells ; Humans ; Laryngeal Neoplasms ; pathology ; Light ; Perylene ; analogs & derivatives ; pharmacology