Relationship Between Radiatio Lung Injury And Endothelial Progenitor Cells

Objective:To investigate the changes of(EPCs)in peripheral blood endothelial progenitor cells(EPCs)in patients with thoracic tumor during different periods of radiotherapy.Radiation therapy is a commonly used non-surgical treatment of cancer.Studies have shown that more than half of patients with lung cancer,esophageal cancer,and other chest tumors are suitable for radiotherapy.Radiation-induced lung injury(RILI)is a serious side effect of radiotherapy for chest tumors.It is an inflammatory reaction caused by injury to normal lung tissue in the radiation field.Among the patients received thoracic radiotherapy,8% to 13% developed severe toxicity,and approximately 1.6% died from serious RILI.However,the underlying molecular and cellular mechanisms of RP are very complex.Several biological factors need to be considered for understanding the molecular events in developing radiation-induced complications in normal tissues.Because vascular ECs is an important target of radiation therapy and EPCs is the precursor cell of vascular ECs,EPCs may be related to the pathogenesis of radiation-induced lung injury(RILI).Method:Fifty cases of lung cancer,aged 30 to 76 years,who received radiotherapy for esophageal carcinoma,were collected from radiotherapy Department of Liaocheng people’s Hospital on July 12,2017.2018.12.The age of 30-76 years old.All patients were eligible for radiotherapy,agreed and received radiotherapy.Before treatment(baseline level),circulating endothelial progenitor cell levels were measured after week 2,week 4,week 6 and after week 12.RILI was evaluated retrospectively 6 weeks after radiotherapy.Result:The number of epcs began to rise 2 weeks after radiotherapy and peaked 4 weeks later.The number of EPCs began to rise 2 weeks after radiotherapy and peaked 4 weeks later.The independent sample t-test and Pearson correlation analysis were used for repeated measurement.It was found that there was no significant difference in the number of endothelial progenitor cells between RILI group and non-RILI group before radiotherapy(baseline level).The number of EPCs in RILI patients after 2 weeks,4 weeks,6 weeks and 12 weeks after radiotherapy was significantly higher than that in non-RILI group.There was a significant difference in the level of EPCs between the RILI group and the non-RILI group(p < 0.01).The correlation analysis showed that EPCs was significantly correlated with RILI(r > 0.5),so there was a significant correlation between EPCs and RILI.Conclusion:Early variations of EPCs levels during 3D-CRT are significantly associated with the risk of RP.Variations of circulating EPCs levels during 3D-CRT may serve as independent predictive factors for RILI.