Project description:Irradiated dying tumor cells play crucial roles in tumor repopulation. However, the transcriptome changes in pancreatic cancer cells after radiation remains unknown. Here we performed RNA-sequencing in pancreatic cancer cell line SW1990 and PANC-1 that were 10Gy irradiated or unirradiated. Bioinformatic analysis revealed that the transcriptomes were significantly changed after radiation. Gene Ontology (GO) analysis revealed that the signaling concerning extracellular vesicles, especially exosomes, were significantly enriched. Further investigation revealed the vital role of irradiated dying tumor cells-derived exosomes in potentiating tumor repopulation.
Project description:We used miRNA-seq and bioinformatics to analyze and annotate the expression profiles exosomal miRNAs in pancreatic cancer cells after radiation, compared with the unirradiated cells. A total of 481 miRNAs were identified, and 284 miRNAs were annotated in miRBase. There were 22 filtered differentially expressed miRNAs (9 for up-regulated and 13 for down-regulated, fold change > 2, p-value < 0.05). This study provides the results of exosomal miRNA change in pancreatic cancer cells after radiation.
Project description:The cells harvested for microarray analysis were high-dose rate (HDR) irradiated, low-dose rate (LDR) irradiated or unirradiated T-47D cells. The HDR-irradiated cells were harvested 24h after a dose of 0.3 Gy at 35 Gy/h, a time where hyper-radiosensitivity (HRS) had returned. The HRS-deficient LDR-irradiated cells were harvested 2 months after a dose of 0.3 Gy at 0.3 Gy/h. LDR-irradiated vs. Control (unirradiated) contains 4 biological replicates. HDR- vs. LDR-irradiated contains 3 biological replicates. HDR-irradiated vs. Control contains 4 biological replicates.
Project description:Osteoradionecrosis of the jaw (ORNJ) is a complication after head and neck radiotherapy that severely affects patients’ quality of life. Currently, an overall understanding of microenvironmental factors of ORNJ is still lacking. Here, we reveal the activation of taurine metabolism in irradiated mandibular stromal cells with scRNA-Seq and the decrease of taurine in irradiated bone marrow mesenchymal stromal cells (BMSCs) with metabolomics. Compared to the unirradiated BMSCs, the taurine uptake of irradiated BMSCs increases. The taurine concentration in peripheral blood and jaws of irradiated mice are significantly lower than the unirradiated mice. Supplementation of taurine promotes osteogenic differentiation, decreases oxidative stress and DNA damage of irradiated BMSCs. Oral administration of taurine significantly promotes survival rate of irradiated mice and promotes osteogenesis of irradiated jaws. Our study sheds light on the role of taurine during the recovery of radiation-induced jaw injury, suggesting a potential non-invasive therapeutic means to combat ORNJ.
Project description:The cells harvested for microarray analysis were high-dose rate (HDR) irradiated, low-dose rate (LDR) irradiated or unirradiated T-47D cells. The HDR-irradiated cells were harvested 24h after a dose of 0.3 Gy at 35 Gy/h, a time where hyper-radiosensitivity (HRS) had returned. The HRS-deficient LDR-irradiated cells were harvested 2 months after a dose of 0.3 Gy at 0.3 Gy/h.
Project description:The precise mechanism of intercellular communication among cancer cells after radiation exposure remains unclear. Exosomes are membrane-enclosed small vesicles constituted by lipid bilayers and are recognized as mediators of intercellular communication that transport a variety of intracellular components, including microRNA (miRNA). Here we identified novel roles of exosomes released from irradiated cells to neighboring cancer cells. To confirm the presence of exosomes in the culture media of the human pancreatic cancer cell line MIAPaCa-2, ultracentrifugation was performed followed by transmission electron microscopy and nanoparticle tracking analysis (NanoSight) using the exosome-specific surface markers CD9 and CD63. Subsequent endocytosis of exosomes was confirmed by fluorescent microscopy. Cell survival after irradiation and following the addition of exosomes was evaluated by a colony-forming assay. Expression of miRNAs in exosomes was then quantified by microarray analysis, while those of Cu/Zn superoxide dismutase (SOD1) and Mn-superoxide dismutase (SOD2) enzymes in MIAPaCa-2 cells were evaluated by western blotting. Results showed that the uptake of irradiated exosomes was significantly higher than that of non-irradiated exosomes. Notably, irradiated exosomes induced higher intracellular levels of ROS and a higher frequency of DNA damage in MIAPaCa-2 cells, as determined by fluorescent microscopy and immunocytochemistry, respectively. Moreover, six upregulated and five downregulated miRNAs were identified in 5 Gy- and 8 Gy-irradiated cells using miRNA microarray analyses. Further analyses using miRNA-mimics and real time reverse transcription PCR identified miR-6823-5p as a possible candidate for SOD1 inhibition, leading to increased intracellular ROS level and DNA damage. This is the first study to demonstrate that irradiated exosomes can enhance the radiation effect via increased intracellular ROS levels in cancer cells, potentially leading to improved understanding of the bystander effect of neighboring cancer cells.
Project description:A time course of OTI CD8 T cells transferred to irradiated syngeneic hosts (or unirradiated hosts as control). Keywords: time-course