Search

The identification of rapid, sensitive and high throughput biomarkers is imperative in order to identify individuals harmed by radiation accidents, and accurately evaluate the absorbed doses of radiation. DNA microarrays have previously been used to evaluate the alterations in growth/differentiation factor 15 (GDF15) gene expression in AHH‑1 human lymphoblastoid cells, following exposure to γ‑rays. The present study aimed to characterize the relationship between the dose of ionizing radiation and the produced effects in GDF‑15 gene expression in AHH‑1 cells and human peripheral blood lymphocytes (HPBLs). GDF‑15 mRNA and protein expression levels following exposure to γ‑rays and neutron radiation were assessed by reverse transcription‑quantitative polymerase chain reaction and western blot analysis in AHH‑1 cells. In addition, alterations in GDF‑15 gene expression in HPBLs following ex vivo irradiation were evaluated. The present results demonstrated that GDF‑15 mRNA and protein expression levels in AHH‑1 cells were significantly upregulated following exposure to γ‑ray doses ranging between 1 and 10 Gy, regardless of the dose rate. A total of 48 h following exposure to neutron radiation, a dose‑response relationship was identified in AHH‑1 cells at γ‑ray doses between 0.4 and 1.6 Gy. GDF‑15 mRNA levels in HPBLs were significantly upregulated following exposure to γ‑ray doses between 1 and 8 Gy, within 4‑48 h following irradiation. These results suggested that significant time‑ and dose‑dependent alterations in GDF‑15 mRNA and protein expression occur in AHH‑1 cells and HPBLs in the early phases following exposure to ionizing radiation. In conclusion, alterations in GDF‑15 gene expression may have potential as a biomarker to evaluate radiation exposure. [ABSTRACT FROM AUTHOR]

Schinifoline (SF), a 4-quinolinone derivative, was found in Zanthoxylum schinifolium for the first time. 4-Quinolinone moieties are thought to have cytotoxic activity and are often used as a tubulin polymerization inhibitors, heterogeneous enzyme inhibitors and antiplatelet agents. However, very little information respect to radiosensitization has focused on SF. This work aimed to investigate the radiosensitizing effect of SF on A549 cells. The cell viability results indicated cytotoxicity of SF on A549 cells, with IC50 values of 33.7 ± 2.4, 21.9 ± 1.9 and 16.8 ± 2.2 μg/mL, respectively, after 6, 12, 24 h treatment with different concentrations, and the 10% or 20% IC50 concentration during 12 h was applied in later experiments. The results of cell proliferative inhibition and clonogenic assay showed that SF enhanced the radiosensitivity of A549 cells when applied before 60Co γ-irradiation and this effect was mainly time and concentration dependent. The flow cytometric data indicated that SF treatment before the irradiation increased the G2/M phase, thus improving the radiosensitivity of A549, leading to cell apoptosis. This paper is the first study that describes the in vitro radiosensitising, cell cycle and apoptotic-inducing effects of schinifoline. [ABSTRACT FROM AUTHOR]

Six compounds were isolated from the stems of Clausena lansium (Lour.) Skeels by repeated sillica gel column chromatography. Their chemical structures were elucidated on the basic of physicochemical and spectroscopic data. Among them, 8-geranyloxypsolaren (3) and 2-methoxy-1-(3-methyl-buten-1-yl)-9H-carbazole-3- carbaldehyde (6) were isolated for the first time from this plant. These compounds were screened for cytotoxicity in human cervical cancer (Hela), leukemia (K562), lung cancer (A549), non-small lung carcinoma (H1299) and liver cancer (SMMC-7721). Within the series of cytotoxic tests, compounds 4-6 displayed potent cytotoxic activity against H1299 and SMMC-7721, with the IC50 values of 6.19 to 26.84 μg/mL. [ABSTRACT FROM AUTHOR]