ABSTRACT
In recent years, heavy ion beams have received great attention in the field of malignant tumor radiotherapy due to their radiation physics and biological characteristics. The high rate of local tumor control is one of its advantages, but the control rate of metastatic lesions is still crucial in the treatment of most malignant tumors. Clinical studies on the combined conventional radiotherapy and immunotherapy suggest that the combination of the two can not only control the primary lesions, but may also reduce or completely eliminate distant metastatic lesions. High linear energy transfer radiation, especially heavy ion beams, may have stronger potential in combined immunotherapy. Therefore, this article focuses on the basic research progress of heavy ion beams regulating anti-tumor immune effects and their combined application with immunotherapy.
ABSTRACT
As a natural plant source of artemisinin,a first-line drug against malaria,Artemisia annua directly affects the extraction process of artemisinin and the source of artemisinin. At present,traditional breeding methods combined with tissue culture are often used to breed high-yield artemisinin-containing new varieties of A. annua. However,the breeding method has the disadvantages of low efficiency and continuous selection. In this study,heavy ion beam irradiation technology was used to observe the specific germplasm resources of A. annua,and the morphological characteristics,agronomic traits and artemisinin content were used as indicators to observe the selection materials and materials. The cultivated new varieties were compared with trials and regional trials. In addition,the new variety of A. annua was identified by SRAP molecular marker technology. The results showed that the new variety of A. annua, " Kehao No.1",had an average yield of 235. 0 kg of dry leaf per mu,which was more than 20% higher than that of the control. Especially,the average artemisinin content was 2. 0%,which was 45% higher than that of the control,and the " Kehao No.1" has high anti-white powder disease,high-yield and high-quality new varieties. Therefore,mutagenic breeding of heavy ion beam irradiation can significantly improve the yield and artemisinin content of the " Kehao No. 1" and it has a good promotion value.
Subject(s)
Artemisia annua/genetics , Artemisinins/analysis , Heavy Ions , Mutagenesis , Phenotype , Plant Breeding , Plants, Medicinal/geneticsABSTRACT
Objective:To investigate the effect of heavy ion beam on the invasion and metastasis associated gene RhoC expression in tongue squamous cell carcinoma Tca8113 cells. Methods:Real-time PCR and Western-blot were used to detect the expression of RhoC mRNA and RhoC protein respectively after Tca8113 cells were irradiated by heavy ion beams of 12 C6+. Results:The expression levels of RhoC mRNA in the experimental group were lower than that in the control group(P<0. 05) except for the levels at 12 h after 2 Gy and 4 Gy 12 C6+ irradiation. In addition, the expression levels of RhoC protein increased in a dose-dependent manner at 12 h af-ter irradiation, reaching a peak at 4 Gy, and subsequently decreased with the increase of irradiation dose. The expression level of RhoC protein was consistent with that of RhoC mRNA. Conclusion:Heavy ion beam of 12 C6+ may inhibit RhoC gene expression in Tca8113 cells.
ABSTRACT
Objective To investigate DNA double-strand breaks and radiosensitization in renal carcinoma 786-O cells induced by fludarabine (FA) combined with different ionizing radiations.Methods The 786-O cells were exposed to FA combined with X-ray or heavy ion beam irradiation.Flow cytometry was used to evaluate the percentage of γH2AX-positive cells and cell cycle.The neutral comet assay was used to detect DNA double-strand breaks.The colony-forming assay was used to evaluate the effects of different treatments on cell survival.Comparison between groups was made by one-way analysis of variance or Dunnet' s t test.Results Compared with FA alone or irradiation alone,FA combined with different ionizing radiations increased DNA double-strand breaks as shown by significantly increased levels of γH2AX (P=0.007,0.001);FA combined with heavy ion beam irradiation lead to a cell cycle block at the radiosensitive G2/M phase and significantly increased the expression of γH2AX in the G2/M phase (P=0.000,0.000);the neutral comet assay revealed that FA combined with irradiation significantly increased DNA sublethal damage (P=0.020,0.060);FA significantly reduced the colony-forming rate after irradiation (P=0.000,0.030;0.001,0.040).Conclusions FA enhances the effects induced by X-ray and heavy ion beam irradiation with different properties.Particularly,FA substantially enhances the cell death induced by heavy ion beam irradiation.