Background Bone marrow hematopoietic function suppression is one of the most common side effects of chemotherapy.After chemotherapy,the bone marrow structure gets destroyed and the cells died,which might cause the hematopoietic function suppression.Heme oxygenase-1 （HO-1） is a key enzyme of antioxidative metabolism that associates with cell proliferation and resistance to apoptosis.The aim of this study was to restore or resist the bone marrow from the damage of chemotherapy by the HO-1 expression of mouse mesenchymal stem cells （mMSCs） homing to the mice which had the chemotherapy-induced bone marrow suppression.Methods One hundred and sixty female Balb/c mice （6-8-weeks old） were randomly divided into four groups.Each group was performed in 40 mice.The control group was intraperitoneally injected for 5 days and tail intravenously injected on the 6th day with normal saline.The chemotherapy-induced bone marrow suppression was established by intraperitoneally injecting cyclophosphamide （CTX） into the mice which performed as the chemotherapy group.The mMSCs were tail intravenously injected into 40 chemotherapically damaged mice which served as the mMSCs group.The difference between the HO-1 group and the mMSCs group was the injected cells.The HO-1 group was tail intravenously injected into the mMSCs that highly expressed HO-1 which was stimulated by hemin.The expression of HO-1 was analyzed by Western blotting and RT-PCR.Cell proliferation was measured using the 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide assay.Histopathologic examinations were performed 1 week after injection.Results Compared with the control group,the expression levels of HO-1 mRNA and protein were significantly higher in the HO-1 group （all P ＜0.05）,even obviously than the mMSCs group.CTX treatment induced apoptosis and inhibited proliferation.After injected,the white blood cell （WBC）,red blood cell （RBC） and platelet （PLT） declined fast and down to the bottom at the 7th day.The bone marrow
Background There are limited eligible clinical markers at present to monitor the progress of chronic myeloid leukemia （CML）.Heme oxygenase-1 （HO-1）,as one of the most important oxidation-regulating enzymes in vivo,suggests the onset and progression of cancer when highly expressed.Furthermore,HO-1 level is related with the occurrence and development of hematological diseases.But the relationship between HO-1 expression and progression/relapse of CML has seldom been studied hitherto.This study aimed to investigate the relationship between them to find out a new molecular marker for prediction.Methods A total of 60 peripheral blood and bone marrow （BM） samples from 25 CML patients in different phases were collected respectively to detect the expressions of HO-1 and bcr/abl using real-time PCR.Routine blood test was performed to detect the changes of leukocyte and platelet counts.The proportion of primitive cells in BM was detected by flow cytometry.The relationship between high HO-1 expression and CML progression and relapse was explored by the analysis of variance by Wilcoxon test and linear regression analysis.The diagnostic accuracy and cutoff values were determined by receiver operating characteristic curve.Results Relative expression of HO-1 mRNA in CML patients peripheral blood was significantly higher than that of donors （P 〈0.0001）,which were 0.57±3.78 and （1.417±1.125）×10-6,respectively.HO-1 expression level in CML patients was 0.061 5±0.062 4,which decreased to 0.009 4±0.006 7 upon CMoR,and remained remarkably higher 0.016 3±0.017 5 than that of normal donors （1.417±1.125）× 10-6,P 〈0.001.When relapse occurred,HO-1 expression significantly increased from 0.020 6±0.021 0 to 3.852±10.285 in CMoR stage and undergoing relapse.According to progression of CML,HO-1 expression level in CML patients increased from CP （0.009 5±0.017 6） to AP （0.028 0±0.055 7） and then to BP （0.276 7± 0.447 0）.And there was a linear correlation between HO-1 expression and proportion
