AIM:To investigate the effect of AG 490 on the expression of VEGF and HIF-1α, and the capacity of invasion in human erythroleukemia (HEL) cells.METHODS:The HEL cells were treated with AG490 at different con-centrations .The cell viability was detected by CCK-8 assay.The apoptosis was detected by Hoechst staining .The apoptosis and the cell cycle were analyzed by flow cytometry .The capacity of migration was evaluated by Transwell assay .The mRNA expression level of JAK2 was measured by RT-PCR.The protein levels of p-JAK2, VEGF and HIF-1αwere determined by Western blot.RESULTS:The HEL cell viabilities were 88%, 75%, 48%, 10%and 0.12%after treated with AG490 at 20, 40, 60, 80 and 100 μmol/L for 48 h, respectively.The results of Hoechst staining showed that brilliant blue cells in 80 μmol/L AG490 group was significantly increased compared with control group for 48 h.The apoptosis rate of 80μmol/L AG490 group was significantly increased compared with control group at 48 h after AG490 treatment.The number of membrane-permeating HEL cells in 20μmol/L AG490 group at 24 h after AG490 treatment was significantly lower than that in control group (P<0.05).The mRNA level of JAK2 decreased in a concentration-dependent manner after the HEL cells were treated with different concentrations of AG 490 for 48 h.The protein levels of p-JAK2, VEGF and HIF-1αwere lower in AG490 treatment groups than those in control group (P<0.05).CONCLUSION: AG490 inhibits the expression of VEGF and HIF-1αin HEL cells by inhibiting JAK2 pathway.

Objective:To investigate the effect of jejunal loop fixation in the reoperation for anastomotic stricture after cholangiojejunostomy.Methods:From Jan 2016 to Jan 2020, clinical data of 15 patients undergoing reoperations for anastomotic stenosis was analyzed retrospectively.Original anastomosis was removed and Roux-en-Y cholangiojejunostomy and jejunal loop fixation were performed in all cases. Two different types of jejunal loop fixation were used. One with a blind loop of 10-15 cm at the proximal side of the anastomosis, which is fixed with a mark of the abdominal wall under the xiphoid process. The second is to mark and fix the jejunal side wall and the right abdominal wall about 10 cm from the distal side of the anastomosis. A T tube is placed in the intestine through the central part of the fixed intestinal wall.Results:Five cases underwent blind loop fixation, 10 cases underwent lateral wall fixation. There were 3 complications after operation, including 1 case of bile fistula, 1 case of incision infection, 1 case of abdominal hemorrhage, all were cured by conservative treatment, and there was no perioperative death. One case had postoperative anastomotic stenosis in the follow-up. The patient underwent jejunal puncture under local anesthesia, and was cured by percutaneous choledochoscopy.Conclusions:The possibility of restenosis should be considered in the reoperation of anastomotic stenosis. The jejunal loop should be fixed and marked during the operation in high risk patients. Once the anastomotic stricture recurred, choledochoscopy could be performed by puncture and dilation of fixed loop of intestine to avoid reopen surgery.

Objective: To investigate the regulation of JAK2 tyrosine kinase inhibitor ruxolitinib on extracellular matrix metalloproteinase (MMP in JAK2V617F positive myeloproliferative neoplasms (MPN) cells. Methods: ①Forty cases of newly diagnosed JAK2V617F positive MPN patients and 15 healthy volunteers as control in Baoding No.1 Hospital between January 2012 and December 2015 were enrolled in this study. JAK2V617F/JAK2 ratio was detected by real-time-PCR; the expression levels of phosphorylation protein tyrosine kinase 2 (p-JAK2) , MMP-2 and MMP-9 in pathological tissues of bone marrow were detected by immunohistochemistry. The bone marrow cells of JAK2V617F positive MPN patients were treated with ruxolitinib, then the migration ability and MMP-2, MMP-9 gene and protein expression levels were detected. ②The human erythroleukemia cell line HEL cells were treated with different concentrations of ruxolitinib (0, 50, 100, 250, 500, 1 000 nmol/L) . The cell viability was detected by CCK-8 test; cell migration ability was tested by transwell chambers. The mRNA expression levels of JAK2, MMP-2 and MMP-9 were detected by real-time-PCR. The protein expression levels of p-JAK2, MMP-2 and MMP-9 were detected by Western blot. Results: ①The expression levels of p-JAK2, MMP-2 and MMP-9 in the newly diagnosed group were significantly higher than control group respectively [ (78.56±24.55) % vs (41.59±17.29) %, P<0.05; (48.25±18.74) % vs (22.79±13.89) %, P<0.05; (53.29±19.28) % vs (15.56±14.96) %, P<0.05]. Spearman correlation analysis showed the positive correlation of MMP-2 and MMP-9 protein expression levels with JAK2V617F mutation (r=0.526, P=0.001; r=0.543, P=0.001) . ②The proliferation of HEL cells was inhibited by different concentrations of ruxolitinib in time and dose dependent manner. ③Cell migration test showed the number of cells leaked to the low chamber in MPN patients bone marrow cells and HEL cells treated with 5 nmol/L of ruxolitinib group were significantly lower than that without ruxolitinib treatment after 24 h [ (154.7±27.5) vs (320.3±67.3) , t=13.47, P<0.05; (70.7±10.5) vs (135.3±16.7) , t=13.89, P<0.05]. The mRNA and protein expression levels of JAK2, MMP-2 and MMP-9 decreased with the increased concentration of ruxolitinib. Conclusion Ruxolitinib inhibits MPN cell migration and expression of MMP-2 and MMP-9 via JAK2 signal pathway.

Objective To determine the effect of rapamycin(Rapa) on JAK2, ABCA3, and the immune checkpoint PD-1/PD-L1 in exosomes derived from JAK2 V617F positive HEL cells. Methods Human erythroleukemia HEL cells (JAK2 V617F mutation-positive) were cultured in vitro, and rapamycin was added at concentrations of 10, 50, and 100 nmol/L. The control group was established and cell proliferation inhibition rate was detected by CCK-8. Based on the inhibition rate of cell proliferation, cells intervened with 10 and 50 nmol/L Rapa were selected. Exosomes were extracted using a kit and identified by Western blot and flow cytometry. JAK2, ABCA3, and PD-1/PD-L1 mRNA changes in exosomes were detected by fluorescent quantitative PCR. The expression of exosome PD-1/PD-L1 protein was determined by flow cytometry. Results The exosomes extracted with the exosome kit all expressed characteristic CD9, CD63, and CD81 proteins, which were consistent with the general characteristics of exosomes. JAK2 mRNA can be detected in exosomes from HEL cells; Rapa reduced exosome production by HEL cells, and dose-dependently decreased gene expression of JAK2, ABCA3, and PD-L1 in exosomes. In addition, Rapa inhibited exosomal PD-L1 protein expression and had no significant effect on PD-1 protein expression. Conclusion HEL cells may transmit JAK2 mutant gene signals via exosomes. Rapa can reduce the production of exosomes and inhibits JAK2 mutated signals delivered by exosomes and suppresses PD-L1 protein expression.

The incidence of hematologic malignancies is increasing, and although new drugs and treatments have made great progress, relapse and drug resistance are still urgent problems to be solved. Exosomes are tiny membrane vesicles secreted in cells that carry lipid bilayer membrane structures including mRNA, microRNA and proteins. It carries and transmits important signaling molecules, forming an entirely new intercellular information transfer system that exhibits a wide range of biological properties and functions in organisms. Tumor cell exosomes are confirmed to contribute to cancer cell proliferation, angiogenesis, invasiveness, distant metastasis and drug resistance. Multiple studies have shown that exosomes from some malignant hematological tumor cells are closely related to tumor resistance. This review summarizes the research progress of exosomes in the mechanism of drug resistance of hematologic malignancies, in order to provide a theoretical basis for the clinical treatment of hematologic malignancies.

Objective To analyze our experience in laparoscopic common bile duct ( CBD) explo-ration using a 5 mm choledochoscope through a micro-incision at the junction between the cystic duct and the CBD for patients with choledocholithiasis and cholecystolithiasis. Methods From January 2014 to May 2018, laparoscopic common bile duct exploration through a micro-incision at the cystic duct-CBD junction was performed in 77 patients with choledocholithiasis and cholecystolithiasis at Beijing Tongren Hospital, Capital Medical University. Results Laparoscopic common bile duct exploration was performed successfully through a micro-incision in 77 patients with primary suturing of the micro-incision. The range of operation time, blood loss, and hospital stay were 65～150 min, 10～50 ml, and 4～9 d respectively. Seven patients developed minor bile leakage postoperatively and were treated successfully after 3 ～7 days of conservative treatment. Conclusion Common bile duct laparoscopic exploration using a choledochoscope for choledocho-lithiasis and cholecystolithiasis through a micro-incision at the junction of cystic duct and CBD was a safe and effective method.

Objective To summarize the experience of the laparoscopic common bile duct exploration for choledocholithiasis and cholecystolithiasis.Methods From Jan 2014 to May 2018,laparoscopic common bile duct exploration were successfully completed in 112 cases of choledocholithiasis and cholecystolithiasis.Results Laparoscopic common bile duct exploration was performed successfully in 14 cases through cystic duct,while in 78 cases through the mini-incision at insertion of cystic duct,and in 20 cases through direct incision of common bile duct.In 3 cases T-tube was placed.9 cases developed bile leakage postoperatively and recovered after 3-7 days of conservative treatment.Conclusion Laparoscopic common bile duct exploration through cystic duct is the first choice of common bile duct exploration followed by mini-incision at insertion of cystic duct.Laparoscopic exploration of common bile duct via choledochotomy was performed when there was abnormal anatomy of cystic duct.

Objective:To study the impact of repeat hepatectomy for patients with post-hepatectomy recurrent hepatocellular carcinoma (HCC).Methods:The data of patients who developed post-hepatecotmy recurrent HCC and underwent repeat hepatectomy at the General Surgery Department of Beijing Tongren Hospital from May 2013 to May 2016 (the Recurrence Group), were retrospectively compared with the data from patients who underwent initial hepatectomy for HCC during the same study period (the Primary Group). The general data, perioperative data, postoperative complications and survival of the two groups were compared.Results:The primary group included 179 patients, consisting of 133 males and 46 females, aged (57.3±11.7) years, with a range from 14.0 to 84.0 years. The recurrence group included 36 patients, consisting of 30 males and 6 females, aged (55.9±11.4) years, with a range from 40.0 to 77.0 years. There were no statistically significant differences between the two groups in gender, age, hepatitis virus infection status, preoperative alpha fetoprotein, Child-Pugh score and indocyanine green retention rate at 15 min ( P>0.05). However, there were statistically significant differences ( P<0.05) between the two groups in operative time [(244.2±84.3)min vs. (283.4±66.8)min], intraoperative blood loss[(428.5±151.6)ml vs. (756.2±187.4)ml], anatomic or nonanatomic hepatectomy, single tumor or multiple tumors, and maximum tumor diameter[(5.81±2.24)cm vs. (3.69±1.55)cm]. There were no statistically significant differences between the two groups in incidences of tumor capsular invasion, tumor thrombus and degrees of tumor differentiation ( P>0.05). There were no statistically significant differences in surgical complication rates ( P>0.05), and in 1-year and 3-year overall and disease free survival rates between the two groups ( P>0.05). Conclusions:Repeat hepatectomy for recurrent HCC after hepatectomy was safe and effective. Its long-term survival outcomes were similar to first hepatectomy for HCC.