RESUMO
【Objective】 To investigate the effect of polymerized human cord hemoglobin (PolyCHb) on the chemosensitivity of human breast cancer MCF-7 cell subcutaneous xenografts in nude mice and its mechanism. 【Methods】 The MCF-7 cells in exponential growth phase were collected and made into suspension cells at a density of 5×107 cells/mL.Subsequently, the cells were inoculated subcutaneously in the right limb of 18 BALB/c-nu nude mice with 0.2 mL cells per mouse to establish subcutaneous xenograft.When the tumor volume reached about 100 mm3, they were randomly divided into chemotherapy group: doxorubicin 5 mg·kg-1, once/week; chemotherapy + PolyCHb group: in addition to doxorubicin (chemotherapy group), PolyCHb 600 mg·kg-1, 3 times/week; the control group: normal saline 90 mg·kg-1, once/week; all were injected through tail vein continuously for 4 weeks.From the day of injection (d 0), the tumor volume of each group of nude mice was measured every 3 days, and the tumor growth curves were drawn accordingly.After 38 days, the tumor growth observation was completed.The tumor was removed and weighed to calculate the tumor inhibition rate.HE staining, immunohistochemistry and TUNEL method were used to observe the pathological changes of tumor tissue, detect the expression of HIF-1α, and detect tumor cell apoptosis respectively.The content of reactive oxygen species (ROS) of each group was determined by fluorescence staining. 【Results】 The tumor volume (mm3) of chemotherapy + PolyCHb group, chemotherapy group and the control group at day 38 were 196.35±103.45 vs 316.29±62.88 vs 519.42±177.33 (P<0.05), and the tumor inhibition rate (%) of chemotherapy + PolyCHb treatment group and chemotherapy group was 62.20 vs 39.11, respectively.HE staining and TUNEL detection showed that cell necrosis and apoptosis in the growth area of tumor tissue increased in chemotherapy + PolyCHb group.Immunohistochemistry and fluorescence staining showed that HIF-1α expression in chemotherapy + PolyCHb group decreased and reactive oxygen species (ROS) content increased. 【Conclusion】 PolyCHb increases the chemosensitivity of subcutaneous xenograft in nude mice with breast cancer, and its mechanism may be related to the increase of ROS in tumor tissue and the promotion of tumor cell apoptosis.
RESUMO
【Objective】 To compare the similarities and differences of polymerized human cord hemoglobin (PolyCHb) and free hemoglobin (FHb) on partial coagulation indexes in vitro, so as to analyze the effect of PolyCHb on coagulation dysfunction. 【Methods】 Using normal saline, two concentrations of FHb and PolyCHb and 36% methemoglobin-containing PolyCHb to mix with fresh whole blood or plasma-rich plasma (PRP) in equal proportions, and incubate at 37°C for 30 minutes to detect prothrombin time (PT), activated partial thromboplastin time (APTT), coagulation factor Ⅱactivity (FⅡ∶C), coagulation factor Ⅴactivity (FⅤ∶C), coagulation factor Ⅷactivity (FⅧ∶C), coagulation factor Ⅸactivity (FⅨ∶C), von Willebrand factor (vWF) and platelet P-selectin (CD62P). 【Results】 1) NaCl group: PT(22.68±1.76) s; APTT(59.58±7.52) s; FⅡ∶C(45.91±3.27) %; FⅤ∶C(30.86±4.43) %; FⅧ∶C(41.32±12.94) %; FⅨ∶C(23.96±5.10) %; vWF (2.14±0.54) mg/L; CD62P(7.44±4.47) %. This group kept as a diluted control. 2) 2% FHb group compared with 7% FHb group: FⅧ∶C (42.16±12.31) %vs (56.64±12.22 ) % (P0.05). 3) There is no significant difference between 2% PolyCHb group and 7% PolyCHb group (P>0.05). 4) There is no significant difference between 2% FHb group and 2% PolyCHb group (P>0.05). 5) 7% FHb group compared with 7% PolyCHb group: PT(23.31±1.34)s vs (21.97±1.56)s (P0.05). 6) 7% PolyCHb group Compared with Met-PolyCHb group: APTT(55.43±5.43) s vs (46.33±4.86)s (P0.05). 【Conclusion】 The effect of PolyCHb on coagulation markers is different from FHb. At the concentration of this study, PolyCHb will not cause coagulation disorders. However, if the methemoglobin (MetHb) content is too high, it will activate the intrinsic coagulation pathway.
