Ursodeoxycholic acid (UDCA) is a naturally occurring, low-toxicity, and hydrophilic bile acid (BA) in the human body that is converted by intestinal flora using primary BA. Solute carrier family 7 member 11 (SLC7A11) functions to uptake extracellular cystine in exchange for glutamate, and is highly expressed in a variety of human cancers. Retroperitoneal liposarcoma (RLPS) refers to liposarcoma originating from the retroperitoneal area. Lipidomics analysis revealed that UDCA was one of the most significantly downregulated metabolites in sera of RLPS patients compared with healthy subjects. The augmentation of UDCA concentration (≥25 μg/mL) demonstrated a suppressive effect on the proliferation of liposarcoma cells. [¹⁵N₂]-cystine and [¹³C₅]-glutamine isotope tracing revealed that UDCA impairs cystine uptake and glutathione (GSH) synthesis. Mechanistically, UDCA binds to the cystine transporter SLC7A11 to inhibit cystine uptake and impair GSH de novo synthesis, leading to reactive oxygen species (ROS) accumulation and mitochondrial oxidative damage. Furthermore, UDCA can promote the anti-cancer effects of ferroptosis inducers (Erastin, RSL3), the murine double minute 2 (MDM2) inhibitors (Nutlin 3a, RG7112), cyclin dependent kinase 4 (CDK4) inhibitor (Abemaciclib), and glutaminase inhibitor (CB839). Together, UDCA functions as a cystine exchange factor that binds to SLC7A11 for antitumor activity, and SLC7A11 is not only a new transporter for BA but also a clinically applicable target for UDCA. More importantly, in combination with other antitumor chemotherapy or physiotherapy treatments, UDCA may provide effective and promising treatment strategies for RLPS or other types of tumors in a ROS-dependent manner.

Objective:To explore the application of an automatic slide-dropping instrument in bone marrow chromosomal karyotyping.Methods:The effects of manual and automatic dropping methods under different environmental humidity were retrospectively analyzed, and the repeatability of the automatic dropping method was analyzed.Results:No statistical difference was found between the results of automatic and manual dropping methods under the optimum ambient humidity and high humidity ( P>0.05). At low humidity, there was a statistical difference between the two methods ( P<0.05). With regard to the repeatability, the coefficient of variations of the automatic dropping method for the number of split phases, the rate of good dispersion and the rate of overlap were all lower than those of the manual dropping method. A statistical difference was also found in the number of split phases ( P<0.05) but not in the discrete excellent rate and overlapping rate between the two methods ( P>0.05). Conclusion:Better effect can be obtained by the automatic dropping instrument. It is suggested to gradually replace manual work with machine.

Objective:To explore the standardized performance of a FISH probe before clinical detection.Methods:The probe sensitivity and specificity of ETV6/RUNX1 were analyzed via interphase and metaphase FISH in 20 discarded healthy bone marrow samples. The threshold system of the probe was established using an inverse beta distribution, and an interpretation standard was established. Finally, a parallel-controlled polymerase chain reaction detection study was conducted on 286 bone marrow samples from patients at our hospital. The clinical sensitivity, specificity, and diagnostic coincidence rate of ETV6/RUNX1 FISH detection were analyzed, and the diagnostic consistency of the two methods was analyzed by the kappa test.Results:The probe sensitivity and specificity of the ETV6/RUNX1 probe were 98.47% and 100%, respectively. When 50, 100, and 200 cells were counted, the typical positive signal pattern cutoffs were 5.81%, 2.95%, and 1.49%, respectively, and the atypical positive signal pattern cutoffs were 13.98%, 9.75%, and 6.26%, respectively. The clinical sensitivity of FISH was 96.1%, clinical specificity was 99.6%, diagnostic coincidence rate was 99.00%, diagnostic consistency test kappa value was 0.964, and P value was <0.001.Conclusion:For FISH probes without a national medical device registration certificate, standardized performance verification and methodology performance verification can be performed using laboratory developed test verification standards to ensure a reliable and accurate reference basis for clinical diagnosis and treatment.

Objective:To investigate the effect of Lamins B2 (LMNB2) on the migration of human retroperitoneal liposarcoma (RPLS) cells SW872.Methods:Immunohistochemistry was used to analyze the the differential expression levels of LMNB2 in 33 RPLS tissue samples . The correlation between LMNB2 expression and clinical prognosis and clinicopathological features was analyzed. siRNA was used to lower the expression level of LMNB2 in tumor cells, and the effect of LMNB2 on the scratch healing ability and migration ability of SW872 cells was examined by using wound-healing assay and transwell migration assay. The expression levels of p-AKT and AKT in each group cells were detected by Western blot.Results:Patients with high LMNB2 expression had a lower recurrence-free survival and overall survival compared to those with low LMNB2 expression, and were more likely to experience recurrence, ( χ2=4.872, P=0.027; χ2=4.180, P=0.041; χ2=7.127, P=0.008). The migration ability of cells was significantly reduced following the silencing of LMNB2 expression ( t=11.240, P<0.01; t=7.445, P<0.01). The expression level of p-AKT in the silencing group was significantly lower than that in the control group, while there was no significant difference in the expression level of AKT between the two groups ( t=9.784, P<0.01). Conclusion:LMNB2 may promote the migration of human retroperitoneal liposarcoma cells SW872 by regulating AKT signaling pathway.

Objective:To establish an in vivo infection model of West Nile virus (WNV) pseudovirus and evaluate the neutralizing activity of antibody WNV-XH1.Methods:A stable cell line that can package the WNV pseudovirus was established in the early stage to prepare the pseudovirus supernatant. The supernatant was concentrated and infected BHK21 cells to detect the titer of the pseudovirus. After intraperitoneal injection of the pseudovirus into C57BL/J mice, bioluminescence imaging was performed to observe the infection status of the pseudovirus in the mice. After simultaneous infection, blood was collected and ELISA was used to detect NS1 levels in mouse serum. The in vivo functional activity of antibody WNV-XH1 was evaluated using the established mouse infection model.Results:Fluorescence was detected in C57BL/J mice infected with WNV pseudovirus, and the NS1 levels in the peripheral blood serum of mice infected with pseudovirus were significantly higher than those of non infected mice (1.453±0.09vs0.305±0.018). After intravenous administration of WNV-XH1 antibody before the attack, the fluorescence signal in the mice decreased and the serum NS1 level decreased (0.384±0.015).Conclusions:A successful in vivo infection model of WNV pseudovirus was established, and it was confirmed that the antibody WNV-XH1 had a protective effect against WNV pseudovirus infection in vivo.

Objective:To investigate the CT imaging features of fat-poor primary retroperitoneal liposarcoma ( PRPLS).Methods:The CT signs of 43 fat-poor PRPLS cases among 128 PRPLS patients confirmed by pathology, including multiple nodules composing or multiple nodules fusing, tumor heterogeneity, were retrospectively evaluated.Results:Of 43 fat-poor PRPLS cases, 28 cases(65%) showed multiple nodules composing or multiple nodules fusing on CT images, 15 cases (35%)demonstrated single mass. Seventeen cases showed tumor heterogeneity on pre-contrast scan, 18 cases showed tumor heterogeneity on contrast scan, 13 cases showed tumor heterogeneity on both pre-contrast and contrast scan, 22 cases (51%)showed tumor heterogeneity on pre-contrast or contrast scan.Conclusion:CT signs of multiple nodules composing or multiple nodules fusing, especially tumor heterogeneity may help establishing diagnosis of fat-poor PRPLS.

Humans ; Retroperitoneal Neoplasms ; Liposarcoma ; Calcium-Binding Proteins ; Mixed Function Oxygenases ; Membrane Proteins ; Muscle Proteins

Objective:To explore the clinical diagnosis and treatment methods and curative effect of retroperitoneal ganglioneuromaMethods:The clinical data of 32 cases of retroperitoneal ganglioneuroma admitted to Peking University International Hospital from Apr 2015 to May 2022 were retrospectively analyzed, and their clinical characteristics, surgical efficacy and prognosis were discussed.Results:Of the 32 patients with retroperitoneal ganglioneuroma, 17 had no obvious clinical symptoms, 7 complained abdominal distension and pain, 6 had lower back pain, and 2 had abdominal mass. Tumors were located near the adrenal and renal regions in 18 cases, on both sides of the spine below the kidneys in 11 cases, and in the pelvis in 3 cases. tumors were single in 28 cases, multiple in 4 cases.Tumors were surrounded by major blood vessels in 12 cases. R 0 or R 1 resection was carried out in 27 cases, and palliative R 2 resection in 5 cases, combined organ resection in 6 cases, and piecemed resection in 8 cases. The maximum tumor diameter was (13.2±4.9)cm, the intraoperative blood loss was 500 (50-6 000 ml), and 6 cases suffered from major postoperative complications. Between patients with tumors encircling and encroaching major blood vessels or not, there were significant differences in age, intraoperative blood loss, R 2 resection rate, and pieceneal resection rate between the two groups ( t=2.44, P=0.021; Z=2.37, P=0.018; χ2=4.57, P=0.033; χ2=11.38, P=0.001). There was no recurrence in patients with R 0 or R 1 resection. Conclusions:The prognosis of complete resection of retroperitoneal ganglioneuroma is good .Major blood vessels encroachment of the tumor often leads to incomplente (R 2) resection.

Objective:To prepare and identify a broad-spectrum antibody FHA3 targeting influenza A virus hemagglutinin (HA).Methods:According to the single-chain antibody fragment (scFv) sequence, the heavy chain (VH) and light chain (VL) variable regions of FHA3 were amplified by PCR and a recombinant plasmid pFRT-IgG1κ-FHA3 was constructed by linking the expression vector pFRT-IgG1κ. FHA3 was expressed in the ExpiCHO system and purified by affinity purification. The binding activity of FHA3 to influenza A virus HA was detected by ELISA. The neutralizing activity of FHA3 was detected in vitro by infecting host cells with pseudovirus. Results:SDS-PAGE showed that high-purity FHA3 was obtained. FHA3 could bind to H1N1 HA, H2N2 HA, H3N2 HA, H5N1 HA, H7N9 HA and H9N2 HA in a concentration-dependent manner. FHA3 had good neutralizing activity in vitro that was it could effectively block the invasion of H5N1 and H7N9 pseudoviruses into target cells at a low concentration of 5 μg/ml and H1N1 pseudovirus at 0.012 5 μg/ml. Conclusions:A broad spectrum antibody targeting HA protein of influenza A virus with neutralizing activity in vitro was obtained.

Objective:To prepare and identify a functional antibody FNA1 targeting the neuraminidase (NA) of influenza A virus N1 subtype.Methods:According to single-chain antibody fragment (scFv) sequence, the heavy chain and light chain variable region sequences of FNA1 were synthesized, and the recombinant expression plasmid pFRT-IgG1κ-FNA1 was constructed by linking the expression vector pFRT-IgG1κ. The FNA1 antibody was expressed in ExpiCHO cells and purified using affinity purification technique. The binding ability of FNA1 to the target proteins, influenza A virus N1 subtype NA antigens, was detected by ELISA. Flow cytometry was performed to analyze the binding ability of FNA1 to the NA antigens expressed on the surface of cell membrane. The in vitro activity of FNA1 against NA was evaluated by infecting 293T cells with pseudovirus. Results:Protein electrophoresis showed that FNA1 with high purity was obtained. FNA1 specifically recognized and bound to N1 subtype NA antigens in a concentration-dependent manner. FNA1 could effectively block NA activity by binding to N1 subtype NA protein expressed on the surface of cell membrane, thus inhibiting the release of packaged pseudovirus from cell surface and further inhibiting target cell infection.Conclusions:An antibody FNA1 targeting influenza A virus N1 subtype NA with in vitro functional activity was obtained.