Reverse effect of Semaphorin-3F on rituximab resistance in diffuse large B-cell lymphoma via the Hippo pathway / 中华医学杂志(英文版)

BACKGROUND@#Exploring the underlying mechanism of rituximab resistance is critical to improve the outcomes of patients with diffuse large B-cell lymphoma (DLBCL). Here, we tried to identify the effects of the axon guidance factor semaphorin-3F (SEMA3F) on rituximab resistance as well as its therapeutic value in DLBCL.@*METHODS@#The effects of SEMA3F on the treatment response to rituximab were investigated by gain- or loss-of-function experiments. The role of the Hippo pathway in SEMA3F-mediated activity was explored. A xenograft mouse model generated by SEMA3F knockdown in cells was used to evaluate rituximab sensitivity and combined therapeutic effects. The prognostic value of SEMA3F and TAZ (WW domain-containing transcription regulator protein 1) was examined in the Gene Expression Omnibus (GEO) database and human DLBCL specimens.@*RESULTS@#We found that loss of SEMA3F was related to a poor prognosis in patients who received rituximab-based immunochemotherapy instead of chemotherapy regimen. Knockdown of SEMA3F significantly repressed the expression of CD20 and reduced the proapoptotic activity and complement-dependent cytotoxicity (CDC) activity induced by rituximab. We further demonstrated that the Hippo pathway was involved in the SEMA3F-mediated regulation of CD20. Knockdown of SEMA3F expression induced the nuclear accumulation of TAZ and inhibited CD20 transcriptional levels via direct binding of the transcription factor TEAD2 and the CD20 promoter. Moreover, in patients with DLBCL, SEMA3F expression was negatively correlated with TAZ, and patients with SEMA3F low TAZ high had a limited benefit from a rituximab-based strategy. Specifically, treatment of DLBCL cells with rituximab and a YAP/TAZ inhibitor showed promising therapeutic effects in vitro and in vivo .@*CONCLUSION@#Our study thus defined a previously unknown mechanism of SEMA3F-mediated rituximab resistance through TAZ activation in DLBCL and identified potential therapeutic targets in patients.

Starting effect of highly active antiretroviral therapy on the incidence of anemia in HIV-infected patients / 上海预防医学

ObjectiveTo investigate the risk factors of anemia in HIV-infected patients receiving highly active antiretroviral therapy （HAART） in the Pudong New Area. MethodsA retrospective cohort study was conducted among HIV-infected patients who started HAART from 2005 to 2020 in Pudong New Area. Cox proportional hazards model was used to analyze the risk factors of anemia， moderate or severe anemia， and chronic anemia. The piecewise linear mixed-effect model was used to analyze the association between initial HAART classes and hemoglobin change in the follow-up. ResultsA total of 2 403 HIV-infected patients were included in the analysis. Among them， there were 357 cases of new onset anemia， 86 cases of chronic anemia and 102 cases of moderate or severe anemia， with the incidence density of 4.41/100 person years， 0.89/100 person years and 0.96/100 person years respectively. Multifactorial Cox regression analysis results showed that female， age >45 years， baseline CD4+ T lymphocyte count （CD4） <200 cells‧μL-1， opportunistic infections， glomerular filtration rate （eGFR） <60 mL‧min-1‧（1.73 m2）-1， and zidovudine （AZT） or protease inhibitor （PIs） based regimens were associated factors for the development of anemia. Female， age >45 years， CD4 <200 cells‧μL-1， opportunistic infections， and AZT-based regimens were associated with the development of chronic anemia. Mild anemia at baseline and AZT-based regimens were associated with the development of moderate or severe anemia. Linear mixed-effects model showed that the use of AZT （-7.87 g‧L-1， 95%CI： -9.42 to -6.32） or PIs （-3.43 g‧L-1， 95%CI： -5.57 to -1.30） was associated with lower Hb at follow-up. ConclusionInitial use of AZT and PIs is associated with progression to anemia and a lower follow-up hemoglobin level. Increased hemoglobin monitoring in users of AZT and PIs may be beneficial， especially during the first 6 months after initiation of HAART.

Correlation between intestinal flora characteristics and hepatic and renal impairments in HIV-infected heterosexual men / 上海预防医学

ObjectiveTo explore the relationship between the intestinal flora and the impairment of liver and kidney in HIV-infected men who have heterosexual sex with healthy women. MethodsFecal samples from 41 HIV-infected heterosexual men who have sex with women （PMSW） and 43 age- and BMI-matched healthy heterosexual men who have sex with women （NMSW） were collected and subjected to 16S rDNA sequencing. The blood levels of AST， ALT， TBIL， UREA， Cr， UA， β2-MG and other liver and kidney function indicators were measured. Bioinformatics methods were used to analyze the characteristics of the intestinal flora of the patients in these two groups， to compare the differential bacteria strains， and to analyze their correlation with liver and kidney function indicators. ResultsIn comparison with NMSW， the alpha diversity of intestinal flora was decreased in PMSW， and the beta diversity analysis showed significant differences in flora characteristics between the two groups （P<0.05）. The abundance of Clostridium， Phylum thick-walled， Trichosporon， and Clostridium tumefaciens decreased but Fusobacteriota increased （LDA score >4）. The comparison of liver and kidney function indexes revealed that AST， β2-MG levels were higher in PMSW than in NMSW， while TBIL was lower in PMSW than in NMSW. The number of patients with abnormal β2-MG was much higher in PMSW than in NMSW， and the difference was statistically significant （P<0.001）. It was also found that AST was negatively correlated with Clostridium （P<0.05）； TBIL was negatively correlated with Clostridium and positively correlated with Phylum thick-walled and Trichosporon （P<0.05）. β2-MG was negatively correlated with Phylum thick-walled， Clostridium， Trichosporon and Rumenococcus （P<0.05） and positively correlated with Clostridium （P<0.05）. ConclusionIn PMSW group， the alpha diversity of the flora is decreased. AST and β2-MG levels are increased， and TBIL level is decreased. These changes were significantly correlated with different strains of bacteria in the intestinal flora.

Phenotypic and genotypic analysis of a pedigree affected with hereditary protein C deficiency / 中华医学遗传学杂志

OBJECTIVE@#To analyze the phenotype and genetic variant in a pedigree affected with inherited protein C (PC) deficiency.@*METHODS@#The proband and her family members (7 individuals from 3 generations) were tested for plasma protein C activity (PC:A), protein C antigen (PC:Ag) content and other coagulation indicators. All of the 9 exons and flanking sequences of the proband's PROC gene were amplified by PCR and sequenced. Suspected variants were verified by reverse sequencing of the proband and her family members. Bioinformatic software was used to analyze the pathogenicity and conservation of the variant site. Swiss-PdbViewer was used to analyze the three-dimensional model and the interaction with the mutant amino acid.@*RESULTS@#The PC:A and PC:Ag of the proband, her grandmother, father and elder brother were decreased to 55%, 52%, 48%, 51% and 53%, 55%, 50%, 56%, respectively. Genetic analysis showed that the four individuals have all carried heterozygous c.1318C>T (p.Arg398Cys) missense mutation in exon 9 of the PROC gene. The score of MutationTaster was 0.991, PROVEAN was -3.72, and FATHMM was -2.49, all predicted it to be a harmful mutation. Phylogenetic analysis also showed that Arg398 was weakly conservative among homologous species. Protein model analysis showed that, in the wild type, Arg398 can form a hydrogen bond with Glu341 and Lys395 respectively, when it was mutated to Cys398, the hydrogen bond with Glu341 disappears and an additional hydrogen bond was formed with Lys395, which has changed the spatial structure of the protein.@*CONCLUSION@#The heterozygous missense mutation c.1318C>T (p.Arg398Cys) of the PROC gene probably underlay the decreased PC:A and PC:Ag in this pedigree.

Phenotypic and genetic analysis of a pedigree affected with hereditary FⅤ deficiency due to a novel deletional variant of F5 gene / 中华医学遗传学杂志

Objective@#To analyze the phenotype and F5 gene variant in a pedigree affected with hereditary coagulation factor Ⅴ (FⅤ) deficiency.@*Methods@#All of the exons, flanking sequences, and 5′ and 3′ untranslated regions of the F5 gene were subjected to PCR and direct sequencing. Suspected variant sites were confirmed by clone sequencing. Influence of the variants was predicted by using software including ClustalX and Mutation Taster.@*Results@#The prothrombin time (PT) and activated partial thromboplastin time (APTT) of the proband were prolonged to 20.3 s and 59.2 s, respectively, while FⅤ activity (FⅤ∶C) and FⅤ antigen (FⅤ∶Ag) were reduced by 13% and 17%, respectively. The FⅤ∶C and FⅤ∶Ag of his father, sister and daughter were decreased to 35%, 37%, 29% and 42%, 46%, 35%, respectively. The proband was found to carry a heterozygous c. 2851delT variant in exon 13 of the F5 gene, which caused a frameshift and resulted in a truncated protein (p.Ser923LeufsX8). In addition, a heterozygous c. 1538G>A (p.Arg485Lys) variant was found in exon 10. The father, sister and daughter of the proband all carried the p. Ser923LeufsX8 variant, while his mother and son carried the heterozygous p. Arg485Lys polymorphism. His younger brother and wife were of the wild type. Bioinformatic analysis showed that p. Ser923 was highly conserved across various species. Mutation Taster scored 1.00 for the p. Ser923LeufsX8 variant, and the result has predicted a corresponding disease.@*Conclusion@#A heterozygous deletional mutation c. 2851delT in exon 13 of the F5 gene and a heterozygous c. 1538G>A polymorphism harbored by the proband may be associated with the decreased FⅤ level in this pedigree.

Phenotypic and genetic analysis of a pedigree affected with hereditary FV deficiency due to a novel deletional variant of F5 gene / 中华医学遗传学杂志

OBJECTIVE@#To analyze the phenotype and F5 gene variant in a pedigree affected with hereditary coagulation factor V (FV) deficiency.@*METHODS@#All of the exons, flanking sequences, and 5' and 3' untranslated regions of the F5 gene were subjected to PCR and direct sequencing. Suspected variant sites were confirmed by clone sequencing. Influence of the variants was predicted by using software including ClustalX and Mutation Taster.@*RESULTS@#The prothrombin time (PT) and activated partial thromboplastin time (APTT) of the proband were prolonged to 20.3 s and 59.2 s, respectively, while FV activity (FV:C) and FV antigen (FV:Ag) were reduced by 13% and 17%, respectively. The FV:C and FV:Ag of his father, sister and daughter were decreased to 35%, 37%, 29% and 42%, 46%, 35%, respectively. The proband was found to carry a heterozygous c.2851delT variant in exon 13 of the F5 gene, which caused a frameshift and resulted in a truncated protein (p.Ser923LeufsX8). In addition, a heterozygous c.1538G to A (p.Arg485Lys) variant was found in exon 10. The father, sister and daughter of the proband all carried the p.Ser923LeufsX8 variant, while his mother and son carried the heterozygous p.Arg485Lys polymorphism. His younger brother and wife were of the wild type. Bioinformatic analysis showed that p.Ser923 was highly conserved across various species. Mutation Taster scored 1.00 for the p.Ser923LeufsX8 variant, and the result has predicted a corresponding disease.@*CONCLUSION@#A heterozygous deletional mutation c.2851delT in exon 13 of the F5 gene and a heterozygous c.1538G to A polymorphism harbored by the proband may be associated with the decreased FV level in this pedigree.

Effects of SDF-1/CXCR4 signal pathway blockade by AMD3100 on the adhesion of leukemia cells to osteoblast niche and the drug resistance of leukemia cells / 中华血液学杂志

<p><b>OBJECTIVE</b>To study the blocking effect of CXCR4 inhibitor AMD3100 on the adhesion of leukemia cells to osteoblast niche, and the reversal of multidrug resistance in leukemia cells.</p><p><b>METHODS</b>Mesenchymal stem cells (MSCs) from leukemia patients were planted on the bio-derived bone scaffolds and then induced into osteoblasts to establish the bio-osteoblast niche. The levels of SDF-1were tested with ELISA. The leukemia cell line MV4-11 cells with FLT3-ITD mutation were inoculated into the bio-osteoblast niche to build a three-dimensional co- culture system. The expression level of CXCR4, adhesion and apoptosis rates of leukemia cells were observed by flow cytometry after incubation with AMD3100 and Ara-C for 24 h and 48 h.</p><p><b>RESULTS</b>(1)The supernatant levels of SDF-1 in cultured osteoblast were (304 ± 18), (410 ± 28) and (396 ± 16) pg/ml on 7 th, 14 th and 21 th day, respectively. It reached the highest on 14 th day. The expression level of CXCR4 in cultured MV4-11 cells was (72 ± 16)%. (2)Adhesion rate of MV4-11 cells to osteoblast niche was (40.1 ± 8.1)% after AMD3100 treatment for 24 h, while that of control group was (65.6 ± 12.1)% (P<0.05). (3)The apoptosis rate of MV4-11 cells incubated with AMD3100 for 24 h was (5.6 ± 0.8)%, while that of control group was (2.5 ± 0.5)%. The apoptosis rates of AMD3100-induced MV4-11 cells were (10.0 ± 2.4)%, (17.8 ± 2.3)% and (25.1 ± 2.4)% after treatment with Ara-C at 0.02, 0.20, 2.00 mg/ml respectively and they were (6.7 ± 1.0)%, (10.3 ± 1.5)%, (16.2 ± 3.1)% respectively in AMD3100-noninduced control group, the difference was significant (P<0.05).</p><p><b>CONCLUSION</b>AMD3100 can block the interaction between osteoblasts niches and leukemia cells, and play an important role in the reversal of multidrug resistance in leukemia cells.</p>