Objective:To explore the effects of neutrophil extracellular traps (NET) on the proliferation and migration of breast cancer cells and the related mechanisms.Methods:The peripheral blood neutrophils were separated using density gradient centrifugation, 100 nmol/L phorbol 12-myristate 13-acetate (PMA) was used to stimulate the formation of NET. Breast cancer cell line MDA-MB-231 was selected and treated with NET (NET group) or deoxyribonucleaseⅠ (DNase Ⅰ) digested NET (NET+DNase Ⅰ group),normal cultured MDA-MB-231 cells were used as the control group. In MDA-MB-231 cells of each group; cell proliferation ability was detected using CCK-8 assay; cell migration was detected by cell scratch assay and Transwell assay; real-time quantitative polymerase chain reaction (qRT-PCR) was used to detect the relative expressions of frizzled homolog 10 (FZD10), cyclin D1, E-cadherin and Vimentin immunofluorescence assay was performed to detect the formation of NET and the expressions of E-cadherin and Vimentin; Western blotting was used to detected the expression of FZD10-Wnt-β-catenin signaling pathway-related proteins.Results:Neutrophils were stimulated with PMA for 4 hours, and immunofluorescence assay results showed that NET exhibited fibrous reticular structure with high expression of citrullinated histone (citH3) and myeloperoxidase (MPO). The CCK-8 assay results showed that the absorbance values of cells in the control group, NET group and NET+DNase Ⅰ group were 1.25±0.06, 2.14±0.15 and 1.47±0.11, respectively, and the difference was statistically significant ( F = 80.60, P < 0.001). The results of scratch assay displayed that the percentage of wound closure in the control group, NET group and NET+DNase Ⅰ group were (36.2±1.3)%, (67.2±2.0)% and (46.3±3.2)%, respectively, and the difference was statistically significant ( F = 140.50, P < 0.001). Transwell assay indicated that the number of migrating cells in the control group, NET group and NET+DNase Ⅰ group were 317±18, 512±23 and 356±23, respectively, and the difference was statistically significant ( F = 75.39, P < 0.001). qRT-PCR assay revealed that the relative expressions of FZD10, cyclin D1 and Vimentin mRNA in the NET group were higher than those in the control group, while the relative expression of E-cadherin mRNA was lower than that in the control group, and the differences were statistically significant (all P < 0.001); the relative expressions of FZD10, cyclin D1 and Vimentin mRNA in the NET+DNase Ⅰ group were lower than those in the NET group, while the relative expression of E-cadherin mRNA was higher than that in the NET group, and the differences were statistically significant (all P < 0.001). Immunofluorescence assay indicated that the number of cells expressing Vimentin in the control group, NET group and NET+DNase Ⅰ group were 35±6, 86±13 and 51±6, respectively, and the difference was statistically significant ( F = 24.65, P = 0.001); the number of cells expressing E-cadherin were 31±4, 11±3 and 24±2, respectively, and the difference was statistically significant ( F = 38.36, P < 0.001). Western blotting results demonstrated that the relative expressions of FZD10, β-catenin and Vimentin proteins in the NET group were higher than those in the control group, while the relative expression of E-cadherin protein was lower than that in the control group; the relative expressions of FZD10, β-catenin and Vimentin proteins in the NET+DNase Ⅰ group were lower than those in the NET group, while the relative expression of E-cadherin protein was higher than that in the NET group. Conclusions:NET may promote the proliferation and migration of breast cancer cells by upregulating the expression of FZD10 and subsequently activating the Wnt-β-catenin signal pathway.

Objective:To explore the application value of minimally invasive plate osteosynthesis(MIPO)and open reduction and internal fixation(ORIF)in patients with middle and lower humeral shaft fractures.Methods:A total of 32 patients with middle and lower humeral shaft fractures treated with MIPO in our hospital from Jun 2020 to Sep 2023 were selected as the observation group,and another 32 patients with middle and lower humeral shaft fractures treated with ORIF were selected as the control group.The perioperative relevant indicators,fracture healing time,pain factors[substance P(SP),prostaglandin E2(PGE2)],pain severity score,upper limb function(Neer score for shoulder joint,Mayo score for elbow joint)before and after surgery,and complications were compared between the two groups.Results:The operation time,incision length,wound healing time,hospitalization time,fracture healing time,and complete weight-bearing time in the observation group were shorter than those in the control group,and the intraoperative blood loss was lower in the observation group(P＜0.05).The levels of serum SP and PGE2 in the observation group were lower than those in the control group at 3 and 5 days after surgery(P＜0.05).The pain scores in the observation group were lower than those in the control group at 1,3,and 5 days after surgery(P＜0.05).The Neer score of the shoulder joint and the Mayo score of the elbow joint in the observation group were higher than those in the control group at 1,3,and 6 months after surgery(P＜0.05).There was no significant difference in the Neer score of the shoulder joint and the Mayo score of the elbow joint between the two groups at 12 months after surgery(P＞0.05).There was no significant difference in the total incidence of complications between the two groups(P＞0.05).Conclusion:Both MIPO and ORIF have good long-term effects and safety in the treatment of middle and lower humeral shaft fractures,but the former can reduce injury,reduce pain,promote fracture healing,and has significant advantages in improving upper limb function in the early stage.

Objective:To explore the application value of minimally invasive plate osteosynthesis(MIPO)and open reduction and internal fixation(ORIF)in patients with middle and lower humeral shaft fractures.Methods:A total of 32 patients with middle and lower humeral shaft fractures treated with MIPO in our hospital from Jun 2020 to Sep 2023 were selected as the observation group,and another 32 patients with middle and lower humeral shaft fractures treated with ORIF were selected as the control group.The perioperative relevant indicators,fracture healing time,pain factors[substance P(SP),prostaglandin E2(PGE2)],pain severity score,upper limb function(Neer score for shoulder joint,Mayo score for elbow joint)before and after surgery,and complications were compared between the two groups.Results:The operation time,incision length,wound healing time,hospitalization time,fracture healing time,and complete weight-bearing time in the observation group were shorter than those in the control group,and the intraoperative blood loss was lower in the observation group(P＜0.05).The levels of serum SP and PGE2 in the observation group were lower than those in the control group at 3 and 5 days after surgery(P＜0.05).The pain scores in the observation group were lower than those in the control group at 1,3,and 5 days after surgery(P＜0.05).The Neer score of the shoulder joint and the Mayo score of the elbow joint in the observation group were higher than those in the control group at 1,3,and 6 months after surgery(P＜0.05).There was no significant difference in the Neer score of the shoulder joint and the Mayo score of the elbow joint between the two groups at 12 months after surgery(P＞0.05).There was no significant difference in the total incidence of complications between the two groups(P＞0.05).Conclusion:Both MIPO and ORIF have good long-term effects and safety in the treatment of middle and lower humeral shaft fractures,but the former can reduce injury,reduce pain,promote fracture healing,and has significant advantages in improving upper limb function in the early stage.

Objective:To explore the effects of neutrophil extracellular traps (NET) on the proliferation and migration of breast cancer cells and the related mechanisms.Methods:The peripheral blood neutrophils were separated using density gradient centrifugation, 100 nmol/L phorbol 12-myristate 13-acetate (PMA) was used to stimulate the formation of NET. Breast cancer cell line MDA-MB-231 was selected and treated with NET (NET group) or deoxyribonucleaseⅠ (DNase Ⅰ) digested NET (NET+DNase Ⅰ group),normal cultured MDA-MB-231 cells were used as the control group. In MDA-MB-231 cells of each group; cell proliferation ability was detected using CCK-8 assay; cell migration was detected by cell scratch assay and Transwell assay; real-time quantitative polymerase chain reaction (qRT-PCR) was used to detect the relative expressions of frizzled homolog 10 (FZD10), cyclin D1, E-cadherin and Vimentin immunofluorescence assay was performed to detect the formation of NET and the expressions of E-cadherin and Vimentin; Western blotting was used to detected the expression of FZD10-Wnt-β-catenin signaling pathway-related proteins.Results:Neutrophils were stimulated with PMA for 4 hours, and immunofluorescence assay results showed that NET exhibited fibrous reticular structure with high expression of citrullinated histone (citH3) and myeloperoxidase (MPO). The CCK-8 assay results showed that the absorbance values of cells in the control group, NET group and NET+DNase Ⅰ group were 1.25±0.06, 2.14±0.15 and 1.47±0.11, respectively, and the difference was statistically significant ( F = 80.60, P < 0.001). The results of scratch assay displayed that the percentage of wound closure in the control group, NET group and NET+DNase Ⅰ group were (36.2±1.3)%, (67.2±2.0)% and (46.3±3.2)%, respectively, and the difference was statistically significant ( F = 140.50, P < 0.001). Transwell assay indicated that the number of migrating cells in the control group, NET group and NET+DNase Ⅰ group were 317±18, 512±23 and 356±23, respectively, and the difference was statistically significant ( F = 75.39, P < 0.001). qRT-PCR assay revealed that the relative expressions of FZD10, cyclin D1 and Vimentin mRNA in the NET group were higher than those in the control group, while the relative expression of E-cadherin mRNA was lower than that in the control group, and the differences were statistically significant (all P < 0.001); the relative expressions of FZD10, cyclin D1 and Vimentin mRNA in the NET+DNase Ⅰ group were lower than those in the NET group, while the relative expression of E-cadherin mRNA was higher than that in the NET group, and the differences were statistically significant (all P < 0.001). Immunofluorescence assay indicated that the number of cells expressing Vimentin in the control group, NET group and NET+DNase Ⅰ group were 35±6, 86±13 and 51±6, respectively, and the difference was statistically significant ( F = 24.65, P = 0.001); the number of cells expressing E-cadherin were 31±4, 11±3 and 24±2, respectively, and the difference was statistically significant ( F = 38.36, P < 0.001). Western blotting results demonstrated that the relative expressions of FZD10, β-catenin and Vimentin proteins in the NET group were higher than those in the control group, while the relative expression of E-cadherin protein was lower than that in the control group; the relative expressions of FZD10, β-catenin and Vimentin proteins in the NET+DNase Ⅰ group were lower than those in the NET group, while the relative expression of E-cadherin protein was higher than that in the NET group. Conclusions:NET may promote the proliferation and migration of breast cancer cells by upregulating the expression of FZD10 and subsequently activating the Wnt-β-catenin signal pathway.

Objective To evaluate the surgical treatments of refractory sclerosing peritonitis related peritoneal dialysis.Methods Clinical data of 15 patients with refractory sclerosing peritonitis related to peritoneal dialysis treated in the General Surgery Department of the 900th Hospital of the Joint Logistics Support Force of the People's Liberation Army from June 30,2014 to May 30,2018.Among them,5 cases underwent"open abdomen peritoneal catheter removal+intestinal adhesiolysis+abdominal infection flushing and drainage with catheter",4 cases underwent"laparoscopic peritoneal catheter removal+intestinal adhesiolysis+abdominal infection flushing and drainage with catheter",3 cases underwent"laparoscopic peritoneal dialysis catheter removal+abdominal infection flushing and drainage with catheter",2 cases underwent"open abdomen peritoneal dialysis catheter removal+abdominal infection flushing and drainage with catheter",and 1 case underwent"laparoscopic examination combined with laparotomy exploration and removal of lower abdominal catheter+intestinal adhesiolysis+abdominal infection flushing and drainage with catheter".Age,gender,clinical symptoms,abdominal CT examination,peripheral blood routine,blood biochemistry,blood C-reactive protein(CRP),white blood cells,biochemistry,and aetiology of peritoneal dialysis fluid were collected and followed up,and the therapeutic effect was evaluated.Results 15 patients were transferred to the Department of Surgery after ineffective treatment in the Department of Internal Medicine.Preoperatively(after 5 days of antibiotic treatment)compared to before antibiotic treatment,there were no significant changes in blood WBC,blood NEUT％,CRP,and peritoneal fluid WBC(P＞0.05).Laparoscopic exploration or laparotomy exploration was performed,during which the peritoneal dialysis catheter was removed and the abdominal infection focus was cleared.A pelvic cavity washout drainage tube was left in place postoperatively.Fourteen patients had a good recovery after surgery,with effective control of peritonitis symptoms and no complications such as intestinal obstruction or enterocutaneous fistula.After the removal of the peritoneal dialysis catheter,all patients switched to hemodialysis.A comparison of inflammatory markers before and after surgery showed a significant decrease after surgery.Three days postoperatively compared to before surgery(after 5 days of antibiotic treatment),there were no significant changes in blood WBC,blood NEUT％,CRP,and peritoneal fluid WBC(P＞0.05).Seven days postoperatively compared to before surgery(after 5 days of antibiotic treatment),there was a significant decrease in blood WBC[(7.43±2.65)× 109/L VS(10.17±5.24)× 109/L],blood NEUT％[(88.23±9.02)％VS(85.07±11.57)％],and CRP[(152.88±113.01)mg/L VS(114.49±92.97)mg/L](P＜0.05);the peritoneal fluid WBC at 7 days postoperatively showed no significant change compared to before surgery(after 5 days of antibiotic treatment)(P＞0.05).The cases were followed up for at least 22 months,and 13 patients did not experience peritonitis or intestinal obstruction again.One patient died 39 days after surgery due to multiple organ failure,and one patient died from other causes after a 2-year follow-up.Conclusion For refractory sclerosing peritonitis related peritoneal dialysis that is ineffective in medical conservative treatment,On the basis of reasonable and effective antibiotics to control infection,surgical intervention should be actively carried out and surgical methods such as surgery should be used to control the progress of peritonitis,reduce mortality and improve the cure rate.

Objective To investigate the association of proton pump inhibitors(PPIs)use with short-term and long-term mortality risk in patients with severe ischemic stroke.Methods This retrospective study based on the U.S.Medical Information Mark for Intensive Care Ⅲ(MIMIC-Ⅲ)database,ICU patients aged ≥18 years with the first ICU admission and a diagnosis of ischemic stroke were finally included in the study.All enrolled subjects were divided into PPIs group and non-PPIs group according to whether they had used PPIs(pantoprazole,lansoprazole and omeprazole)during hospitalization.Kaplan-Meier survival analyses and Cox regression models were used to analyze the association between the use of PPIs and the risk of ICU death,30 d risk of death,90 d risk of death in patients with severe ischemic stroke.Results A total of 1 015 patients were included,402 cases in the PPIs group and 613 in the non-PPIs group.The ICU-mortality,30 d and 90 d mortality were 15.37％,13.60％and 20.10％,respectively.Kaplan-Meier survival analyses illustrated that the PPIs group survived better than non-PPIs group in ICU mortality analysis(P=0.002).In Cox regression analysis,after adjustment for potential confounders,the hazard ratio(HR)for ICU mortality in the PPIs group relative to the non-PPIs group was 0.671 9(95％CI 0.478 8 to 0.942 8,P=0.021),but there was no significant difference between 30 d and 90 d mortality(P＞0.05).Conclusion In patients with severe ischemic stroke,the use of PPIs may be effective in reducing the risk of ICU death,but does not improve 30 d and 90 d risk of death in patients.

Objective:To compare the clinical outcomes of arthroscopic external tension band fixation versus open reduction and internal fixation in the treatment of greater tubercle fracture of the humerus.Methods:A retrospective cohort study was conducted on 55 patients with greater tubercle fracture of the humerus admitted to Taizhou Hospital of Zhejiang Province from September 2019 to June 2022, including 24 males and 31 females, aged 26-80 years [(61.7±10.5)years]. Out of them, 35 patients treated with open reduction and internal fixation (open reduction group), and 20 patients were treated with external anchor tension band under arthroscopy (arthroscopy group). The operation time, and the Visual Analogue Scale (VAS) score, American Shoulder and Elbow Surgeons (ASES) score, Constant-Murley score and shoulder active range of motion (anterior flexion, abduction and posterior extension) before operation, at 1 month after operation and at the last follow-up were compared between the two groups. Bone healing was observed in both groups at the last follow-up. Postoperative complications were compared between the two groups.Results:All the patients were followed up for 12-29 months [(16.9±4.0)months]. There was no significant difference in operation time between the two groups ( P>0.05). There were no significant differences in the VAS score, ASES score, Constant-Murley score and shoulder active range of motion between the two groups before operation ( P>0.05). The VAS score of the arthroscopy group was 3(2, 3)points at 1 month after operation, which was significantly lower than that of the open reduction group [4(3, 4) points] ( P<0.01). No significant difference was found in the VAS score at the last follow-up between the two groups ( P>0.05).The ASES scores of the arthroscopy group were (70.6±4.2)points and (90.2±3.7)points at 1 month after operation and at the last follow-up respectively, which were significantly higher than those of the open reduction group [(64.7±6.4)points and (87.5±4.9)points respectively] ( P<0.05 or 0.01). There was no significant difference in the Constant-Murley score between the arthroscopy group [(71.8±4.3)points] and the open reduction group [(70.9±5.3)points] at 1 month after operation ( P>0.05), while the Constant-Murley score of the arthroscopy group was (94.1±3.1)points at the last follow-up, which was significantly higher than that of the open reduction group [(89.2±4.7)points] ( P<0.01). At 1 month after operation and at the last follow-up, ranges of motion of the anterior flexion, abduction and posterior extension were (52.7±12.3)° and (140.0±16.9)°, (57.4±8.6)° and (125.0±14.3)°, and 16(15, 19)° and 25(20, 30)° in the arthroscopy group respectively, which were significantly higher than those in the open reduction group [(42.2±5.2)° and (110.9±14.0)°, (52.8±6.0)° and (103.7±11.7)°, and 10(10, 20)° and 16(15, 25)° respectively] ( P<0.05 or 0.01). At the last follow-up, it was found that bony union was achieved in both groups. There were no obvious complications such as incision infection or joint stiffnessin both groups. In the open reduction group, 2 patients had internal fixation failure within 1-3 months after operation but was treated with revision operation; 6 patients developed shoulder stiffness at 3-6 months after operation but had outpatient rehabilitation. The incidence rate of postoperative complications in the arthroscopy group [0%(0/20)] was significantly lower than that in the open reduction group [23%(8/35)] ( P<0.05). Conclusion:Compared with open reduction and internal fixation with plates and screws, arthroscopic external anchor tension band fixation in the treatment of greater tuberosity fracture of the humerus has the advantages of earlier pain relief, better shoulder functional improvement, better recovery of shoulder mobility, and fewer complications.

Objective:To explore the effect of NOD-like receptor thermal protein 3 ( NLRP3) knockout in γ-aminobutyric acid (GABA)-ergic neurons in the hippocampal CA1 area on improving cognitive dysfunction in mice after traumatic brain injury (TBI). Methods:Forty-eight healthy male NLRP3 flox/flox mice weighing 25-28 g were randomly divided into 4 groups ( n=12): sham-operated+control virus group (SV group), sham-operated+ NLRP3 specific knockout group (SG group), TBI+control virus group (TV group), TBI+ NLRP3 specific knockout group (TG group). TBI in the TV and TG groups was established by free-fall method, while surgical procedures such as scalp incision and cranial window opening without impact were given to the SV and SG groups. Adenovirus was injected into the hippocampal CA1 area of SG and TG groups 21 d before TBI to induce NLRP3 specific knockout in GABA-ergic neurons in the hippocampal CA1 area; empty virus was injected into the CA1 area of SV and TV groups. Cognitive function was evaluated using novel object recognition test 30 and 31 d after TBI, and learning and memory functions were assessed using Morris water maze test 32-36 d after TBI. Field potentials in the hippocampal CA1 area were recorded during novel object recognition 31 d after TBI. After behavioral tests, these mice were sacrificed. Immunofluorescent staining was used to detect the fluorescent intensity of microtubule-associated protein2 (MAP2), glutamic acid decarboxylase 67 (GAD67), and postsynaptic density protein 95 (PSD95) in the hippocampal CA1 area, as well as percentage of pyroptosis-associated inflammatory factor interleukin-18 (IL-18)/GAD67 double-positive neurons in total GAD67 positive neurons. Results:Compared with the SV and SG groups, the TV and TG groups had decreased novel object recognition index, decreased number of platform crossings during the experimental period, increased escape latency on day 3 and day 4 of the training period in Morris water maze test, decreased θ and γ oscillation power in the hippocampal CA1 area during novel object recognition, decreased fluorescent intensity of MAP2, GAD67, and PSD95 in the hippocampal CA1 area, increased percentage of IL-18/GAD67 double-positive neurons, with significant differences ( P<0.05). Compared with the TV group, the TG group had increased novel object recognition index, increased number of platform crossings in Morris water maze test, decreased escape latency during the training period, increased θ and γ oscillation power in the hippocampal CA1 area during novel object recognition, increased fluorescence intensity of MAP2, GAD67, and PSD95 in the hippocampal CA1 area, decreased percentage of IL-18/GAD67 double-positive neurons, with significant differences ( P<0.05). Conclusion:Specific inhibition of NLRP3 expression in GABA-ergic neurons in the hippocampal CA1 area can improve cognitive dysfunction in mice after TBI, whose mechanism may be related to inhibited GABA-ergic neuronal pyroptosis in the hippocampal CA1 area.

Objective:To evaluate the role of astrocytic NOD-like receptor protein 3 (NLRP3) in the lateral hypothalamus (LHA) in anxiety-like behaviors after hemorrhagic shock and resuscitation in mice.Methods:Forty-eight clean-grade male C57BL/6 mice, aged 10 weeks, weighing 25-30 g, were divided into 4 groups ( n=12 each) using a random number table method: sham operation group (group C), hemorrhagic shock and resuscitation group (group H), hemorrhagic shock and resuscitation + adeno-associated virus group (group HI), and hemorrhagic shock and resuscitation + control virus group (group HIV). The model of hemorrhagic shock and resuscitation was developed by bleeding and re-transfusion through the femoral vein in H, HI and HIV groups. At 21 days before developing the model, AAV-GfaABC1D-EGFP-Cre was injected into bilateral LHA in group HI, and AAV-GfaABC1D-EGFP was administered as a control in group HIV. Anxiety-like behaviors were evaluated by EPM-maze and bead-burying tests at 14 days after resuscitation. Mice were immediately sacrificed at the end of behavioral tests, and LHA-containing brain tissues were obtained for determination of co-localization of NLRP3 with glial fibrillary acidic protein (GFAP), the fluorescence intensity of Wisteria floribunda agglutinin was measured using immunofluorescent staining to reflect the expression of extracellular matrix in the LHA, and the percentage of cleaved caspase-1/GFAP and IL-18/GFAP positive cells in total cells was calculated. Results:Compared with group C, the number of buried beads and percentage of time of staying at the open arm were significantly decreased, the expression of extracellular matrix in the LHA was down-regulated, and the percentage of cleaved caspase-1/GFAP and IL-18/GFAP positive cells was increased in H, HI and HIV groups, and the co-localization coefficient of NLRP3 and GFAP was significantly decreased in group HI ( P<0.01). Compared with group H, the number of buried particles and percentage of time of staying at the open arm were significantly decreased, the expression of extracellular matrix in the LHA was up-regulated, the co-location coefficient of NLRP3 and GFAP was decreased, the percentage of cleaved caspase-1/GFAP and IL-18/GFAP positive cells was decreased ( P<0.01), and no significant change was found in the parameters mentioned above in group HIV ( P>0.05). Conclusions:Anxiety-like behaviors after hemorrhagic shock and resuscitation is associated with astrocytic NLRP3-induced pyroptosis in the LHA and reduction of extracellular matrix in mice.

Objective:To explore the effects of breast cancer mesenchymal stem cells (BC-MSC) on the proliferation and migration of breast cancer MCF-7 cells and the related mechanisms.Methods:The resected cancer tissues and paracancerous tissues were taken from breast cancer patients after surgery, and the bone marrow samples of healthy people were selected. BC-MSC, breast cancer paracancerous mesenchymal stem cells (BCN-MSC) and bone marrow mesenchymal stem cells (BM-MSC) of healthy people were isolated and cultured by tissue adhesion method, and their differentiation ability was induced by the addition of osteogenic and lipogenic induction, and their surface markers were detected by flow cytometry. The supernatants of BC-MSC, BCN-MSC and BM-MSC of healthy people cultured for 48 h were collected and used for the culture of MCF-7 cells as BC-MSC group, BCN-MSC group and BM-MSC group, respectively, and the control group was the conventional cultured MCF-7 cells. The proliferation ability of MCF-7 cells in each group was detected by methyl thiazol tetrazolium (MTT) assay, the clone formation ability of MCF-7 cells was detected by plate cloning assay, the migration ability of MCF-7 cells was detected by Transwell assay, and the mRNA relative expressions of interleukin (IL)-6 and epithelial mesenchymal transition (EMT)-related genes (E-cadherin, vimentin, snail) were detected by quantitative real-time fluorescence polymerase chain reaction (qRT-PCR) in MCF-7 cells. Western blotting was used to detect expressions of p-STAT3, E-cadherin, vimentin and snail proteins in MCF-7 cells. Luminex liquid microarray technology was used to detect cytokine levels in culture supernatants of different mesenchymal stem cells (MSC). IL-6 neutralizing antibody was added into the supernatant of BC-MSC, MCF-7 cells were cultured with the supernatant (BC-MSC+IL-6 neutralizing antibody group), and then the proliferation and migration abilities of MCF-7 cells were tested, as well as the expression changes of related genes and proteins.Results:BC-MSC, BCN-MSC and BM-MSC were successfully isolated; BC-MSC had positive expressions of CD29, CD44 and CD90 and negative expressions of CD14, CD34 and CD45, which were in line with the characteristics of MSC. MTT assay showed that the absorbance values of MCF-7 cells cultured for 48 h in the control group, BC-MSC group, BCN-MSC group and BM-MSC group were 0.31±0.02, 0.54±0.03, 0.43±0.02 and 0.42±0.02, respectively, and the difference was statistically significant ( F = 56.52, P < 0.05); the results of plate cloning experiments showed that the number of clones in each petri dish of the four groups were 180±9, 439±17, 319±16 and 306±19, respectively, and the difference was statistically significant ( F = 222.70, P < 0.05); Transwell assay showed that the numbers of membrane-penetrating cells in the four groups were 6.5±1.0, 23.2±2.4, 16.0±1.3 and 14.8±2.0, respectively, with the statistically significant difference ( F = 49.44, P < 0.05); qRT-PCR assay showed that the relative expressions of IL-6 mRNA in the control group, BC-MSC group, BCN-MSC group and BM-MSC group were 1.07±0.11, 13.79±3.80, 6.68±1.66 and 6.12±1.52, respectively, and the difference was statistically significant ( F = 107.60, P < 0.05), and the relative expression of E-cadherin mRNA in MCF-7 cells of BC-MSC, BCN-MSC and BM-MSC groups was lower than that of the control group, while the relative expressions of vimentin and snail mRNA were higher than those of the control group, and the differences were statistically significant (all P < 0.05). Western blotting assay showed that the relative expression of E-cadherin mRNA in MCF-7 cells of BC-MSC, BCN-MSC and BM-MSC groups was lower than that of the control group. Western blotting showed that the level of E-cadherin protein in BC-MSC, BCN-MSC and BM-MSC groups was lower than that in the control group, and the levels of vimentin and snail proteins were higher than those in the control group; Luminex liquid microarray technology showed that the content of IL-6 cytokine in the supernatants of BC-MSC, BCN-MSC and BM -MSC cultures were higher, and the relative expressions were 1.75±0.21, 1.00±0.10 and 0.96±0.08, respectively, and the difference was statistically significant ( F = 43.22, P < 0.05). The results of MTT assay showed that the absorbance values of MCF-7 cells in BC-MSC group and BC-MSC+IL-6 neutralizing antibody group were 0.56±0.05 and 0.42±0.04, respectively, and the difference was statistically significant ( t = -3.11, P < 0.05); the results of Transwell assay showed that the numbers of membrane-penetrating cells in the two groups were 30.3±1.5 and 17.3±2.1, respectively, and the difference was statistically significant ( t = -7.12, P < 0.05); qRT-PCR assay showed that the relative expressions of E-cadherin mRNA were 0.44±0.05 and 0.76±0.05 ( t = 6.40, P < 0.01), the relative expressions of vimentin mRNA were 2.90±0.21 and 1.79±0.21 ( t = 5.29, P < 0.01), and the relative expressions of snail mRNA were 3.20±0.20 and 1.91±0.30 ( t = 2.16, P < 0.01); Western blotting assay showed that the degrees to down-regulate the expression of E-cadherin protein and up-regulate the expressions of vimentin and snail proteins in the BC-MSC+IL-6 neutralizing antibody group were weakened compared with the BC-MSC group. Conclusions:BC-MSC can promote the proliferation and migration of breast cancer MCF-7 cells probably through activating IL-6-STAT3 signaling pathway-induced EMT by its secretion of IL-6.