[Diagnosis status and genetic characteristics analysis of Fanconi anemia in China]

Objective: To analyze the clinical and molecular diagnostic status of Fanconi anemia (FA) in China. Methods: The General situation, clinical manifestations and chromosome breakage test and genetic test results of 107 pediatric FA cases registered in the Chinese Blood and Marrow Transplantation Registry Group (CBMTRG) and the Chinese Children Blood and Marrow Transplantation Registry Group (CCBMTRG) from August 2009 to January 2022 were analyzed retrospectively. Children with FANCA gene variants were divided into mild and severe groups based on the type of variant, and Wilcoxon-test was used to compare the phenotypic differences between groups. Results: Of the 176 registered FA patients, 69 (39.2%) cases were excluded due to lack of definitive genetic diagnosis results, and the remaining 107 children from 15 hospitals were included in the study, including 70 males and 37 females. The age at transplantation treatment were 6 (4, 9) years. The enrolled children were involved in 10 pathogenic genes, including 89 cases of FANCA gene, 7 cases of FANCG gene, 3 cases of FANCB gene, 2 cases of FANCE gene and 1 case each of FANCC, FANCD1, FANCD2, FANCF, FANCJ, and FANCN gene. Compound heterozygous or homozygous of loss-of-function variants account for 69.2% (72/104). Loss-of-function variants account for 79.2% (141/178) in FANCA gene variants, and 20.8% (37/178) were large exon deletions. Fifty-five children (51.4%) had chromosome breakage test records, with a positive rate of 81.8% (45/55). There were 172 congenital malformations in 80 children.Café-au-Lait spots (16.3%, 28/172), thumb deformities (16.3%,28/172), polydactyly (13.9%, 24/172), and short stature (12.2%, 21/172) were the most common congenital malformations in Chinese children with FA. No significant difference was found in the number of congenital malformations between children with severe (50 cases) and mild FANCA variants (26 cases) (Z=-1.33, P=0.185). Conclusions: FANCA gene is the main pathogenic gene in children with FA, where the detection of its exon deletion should be strengthened clinically. There were no phenotypic differences among children with different types of FANCA variants. Chromosome break test is helpful to determine the pathogenicity of variants, but its accuracy needs to be improved.

[Bioinformatics analysis and key gene verification of sepsis myocardial macrophage microarray data based on GEO database]

Objective: Bioinformatics analysis was used to screen differentially expressed genes (DEGs) in macrophages of sepsis myocardial injury and to verify key genes. Methods: Experiment 1 (gene chip and bioinformatics analysis): The gene chip data GSE104342 of cardiac macrophages in septic mice was downloaded from Gene Expression Omnibus database. DEGs were obtained by R language analysis. DAVID online database was used to obtain gene ontology and kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis of DEGs. STRING online database was used for protein-protein interaction network analysis of DEGs, and then key genes were screened by using Cytoscape software and molecular complex detection (MCODE) plug-ins. Experiment 2 (sepsis model construction and related protein verification): Ten male C57BL/6 mice, aged 8-14 weeks. Five mice were randomly selected as control group, and 5 mice were selected as the sepsis group by building a mice sepsis model in vivo. Echocardiography was used to detect the cardiac function. Hematoxylin-eosin staining was used to assess the cardiac morphology. TUNEL staining was used to evaluate cardiomyocyte apoptosis. Immunofluorescence staining was used to detect the expression of differentiation antigen cluster 206 (CD206),inducible nitric oxide synthases (iNOS),F4/80,suppressor of cytokine signaling 3 (Socs3) ,interleukin 1 receptor antagonist (Il1rn) and chemokine C-C motif ligand 7 (Ccl7) protein. RAW264.7 macrophages were cultured in vitro and divided into 2 groups: LPS groupstimulated by lipopolysaccharide (LPS, 1 mg/L) and blank control group treated with equal-volume phosphate buffer solution. Reverse transcription-polymerase chain reaction (RT-PCR) was used to evaluate the expression of Socs3, Il1rn and Ccl7 in vitro. Results: Experiment 1: 24 647 genes were screened in GSE104342 dataset and 177 genes (0.72%) were differential expression, including 120 up-regulated genes and 57 down-regulated genes. Gene ontology enrichment analysis showed that DEGs were mainly involved in inflammatory response, immune response, apoptosis regulation and antigen processing and presentation. KEGG signaling pathway analysis showed that DEGs in cardiac macrophages of septic mice were mainly enriched in cytokine-cytokine receptor interaction, tumor necrosis factor signaling pathway, NOD like receptor signaling pathway. Three hub genes were obtained by STRING and Cytoscape analysis, including Socs3, Il1rn and Ccl7. Experiment 2: In vivo, it was found that compared with the control group, the cardiac function of the sepsis mice decreased significantly, the myocardial cells were significantly edema, inflammatory cell infiltration, myocardial fiber rupture, some myocardial nuclei dissolved and disappeared, and the cardiomyocyte apoptosis increased, suggesting that the sepsis myocardial injury model of mice was successfully constructed. Compared with the control group, the expression of CD206 in the myocardium of septic mice was down-regulated, the expression of iNOS, F4/80, Socs3, Il1rn and Ccl7 were up-regulated. In addition, there was co-localization between Socs3, Il1rn, Ccl7 and F4/80 protein. Compared with the blank control group, the expression of Socs3, Il1rn and Ccl7 significantly upregulated after LPS intervention in vitro by RT-PCR. Conclusions: The selected key genes Socs3, Il1rn and Ccl7 were up-regulated in myocardial macrophages of septic mice. Socs3, Il1rn and Ccl7 are expected to become new targets for the diagnosis and treatment of sepsis cardiac injury.

[Efficacy of decitabine combined with low dose chemotherapy on children with acute myeloid leukemia]

Objective: To evaluate the efficacy of decitabine combined with low dose chemotherapy (LDC) in the treatment of high-risk, refractory and relapsed pediatric acute myeloid leukemia (AML). Methods: Clinical data of 19 AML children treated with decitabine combined with LDC in the Department of Hematology, Children's Hospital of Soochow University from April 2017 to November 2019 were analyzed retrospectively. The therapeutic response, adverse effects and survival status were analyzed,and the outcomes of patients were followed up. Results: Among 19 AML cases, there were 10 males and 9 females. Five cases were high-risk AML, 7 cases were refractory AML, and 7 cases were relapsed AML. After one course of decitabine+LDC treatment, 15 cases achieved complete remission, 3 cases got partial remission, and only 1 case didn't get remission. All patients received allogeneic hematopoietic stem cell transplantation as consolidation therapy. The follow-up time of all cases was 46 (37, 58) months, 14 children had survived. The cumulative three-year overall survival rate was (79±9) %, events free survival rates was (68±11) %, and recurrence free survival rate was (81±10) %. The most common adverse effects related to the induction treatment were cytopenia (19 cases) and infection (16 cases).There were no treatment-related death during the therapy. Conclusion: Decitabine combined with LDC is a safe and effective option for high-risk, refractory and relapsed AML children, which provides an opportunity for HSCT.

Potent GCN2 Inhibitor Capable of Reversing MDSC-Driven T Cell Suppression Demonstrates In Vivo Efficacy as a Single Agent and in Combination with Anti-Angiogenesis Therapy

General control nonderepressible 2 (GCN2) protein kinase is a cellular stress sensor within the tumor microenvironment (TME), whose signaling cascade has been proposed to contribute to immune escape in tumors. Herein, we report the discovery of cell-potent GCN2 inhibitors with excellent selectivity against its closely related Integrated Stress Response (ISR) family members heme-regulated inhibitor kinase (HRI), protein kinase R (PKR), and (PKR)-like endoplasmic reticulum kinase (PERK), as well as good kinome-wide selectivity and favorable PK. In mice, compound 39 engages GCN2 at levels ≥80% with an oral dose of 15 mg/kg BID. We also demonstrate the ability of compound 39 to alleviate MDSC-related T cell suppression and restore T cell proliferation, similar to the effect seen in MDSCs from GCN2 knockout mice. In the LL2 syngeneic mouse model, compound 39 demonstrates significant tumor growth inhibition (TGI) as a single agent. Furthermore, TGI mediated by anti-VEGFR was enhanced by treatment with compound 39 demonstrating the complementarity of these two mechanisms.

EBV+ tumors exploit tumor cell-intrinsic and -extrinsic mechanisms to produce regulatory T cell-recruiting chemokines CCL17 and CCL22

The Epstein-Barr Virus (EBV) is involved in the etiology of multiple hematologic and epithelial human cancers. EBV+ tumors employ multiple immune escape mechanisms, including the recruitment of immunosuppressive regulatory T cells (Treg). Here, we show some EBV+ tumor cells express high levels of the chemokines CCL17 and CCL22 both in vitro and in vivo and that this expression mirrors the expression levels of expression of the EBV LMP1 gene in vitro. Patient samples from lymphoblastic (Hodgkin lymphoma) and epithelial (nasopharyngeal carcinoma; NPC) EBV+ tumors revealed CCL17 and CCL22 expression of both tumor cell-intrinsic and -extrinsic origin, depending on tumor type. NPCs grown as mouse xenografts likewise showed both mechanisms of chemokine production. Single cell RNA-sequencing revealed in vivo tumor cell-intrinsic CCL17 and CCL22 expression combined with expression from infiltrating classical resident and migratory dendritic cells in a CT26 colon cancer mouse tumor engineered to express LMP1. These data suggest that EBV-driven tumors employ dual mechanisms for CCL17 and CCL22 production. Importantly, both in vitro and in vivo Treg migration was effectively blocked by a novel, small molecule antagonist of CCR4, CCR4-351. Antagonism of the CCR4 receptor may thus be an effective means of activating the immune response against a wide spectrum of EBV+ tumors.

Structure-Based Design of Potent, Selective, and Orally Bioavailable VPS34 Kinase Inhibitors

VPS34 is a class III phosphoinositide 3-kinase involved in endosomal trafficking and autophagosome formation. Inhibitors of VPS34 were believed to have value as anticancer agents, but genetic and pharmacological data suggest that sustained inhibition of VPS34 kinase activity may not be well tolerated. Here we disclose the identification of a novel series of dihydropyrazolopyrazinone compounds represented by compound 5 as potent, selective, and orally bioavailable VPS34 inhibitors through a structure-based design strategy. A water-interacting hydrogen bond acceptor within an appropriate distance to a hinge-binding element was found to afford significant VPS34 potency across chemical scaffolds. The selectivity of compound 5 over PIK family kinases arises from interactions between the hinge-binding element and the pseudo-gatekeeper residue Met682. As recent in vivo pharmacology data suggests that sustained inhibition of VPS34 kinase activity may not be tolerated, structure-activity relationships leading to VPS34 inhibition may be helpful for avoiding this target in other ATP-competitive kinase programs.

Novel Piperidinyl-Azetidines as Potent and Selective CCR4 Antagonists Elicit Antitumor Response as a Single Agent and in Combination with Checkpoint Inhibitors

The C-C chemokine receptor 4 (CCR4) is broadly expressed on regulatory T cells (T_reg) as well as other circulating and tissue-resident T cells. T_reg can be recruited to the tumor microenvironment (TME) through the C-C chemokines CCL17 and CCL22. T_reg accumulation in the TME has been shown to dampen the antitumor immune response and is thought to be an important driver in tumor immune evasion. Preclinical and clinical data suggest that reducing the T_reg population in the TME can potentiate the antitumor immune response of checkpoint inhibitors. We have developed small-molecule antagonists of CCR4, featuring a novel piperidinyl-azetidine motif, that inhibit the recruitment of T_reg into the TME and elicit antitumor responses as a single agent or in combination with an immune checkpoint blockade. The discovery of these potent, selective, and orally bioavailable CCR4 antagonists, and their activity in in vitro and in vivo models, is described herein.

Structure, Chemical Synthesis, and Biosynthesis of Prodiginine Natural Products

The prodiginine family of bacterial alkaloids is a diverse set of heterocyclic natural products that have likely been known to man since antiquity. In more recent times, these alkaloids have been discovered to span a wide range of chemical structures that possess a number of interesting biological activities. This review provides a comprehensive overview of research undertaken toward the isolation and structural elucidation of the prodiginine family of natural products. Additionally, research toward chemical synthesis of the prodiginine alkaloids over the last several decades is extensively reviewed. Finally, the current, evidence-based understanding of the various biosynthetic pathways employed by bacteria to produce prodiginine alkaloids is summarized.

Catalytic Enantioselective Dihalogenation and the Selective Synthesis of (-)-Deschloromytilipin A and (-)-Danicalipin A

A titanium-based catalytic enantioselective dichlorination of simple allylic alcohols is described. This dichlorination reaction provides stereoselective access to all common dichloroalcohol building blocks used in syntheses of chlorosulfolipid natural products. An enantioselective synthesis of ent-(-)-deschloromytilipin A and a concise, eight-step synthesis of ent-(-)-danicalipin A are executed and employ the dichlorination reaction as the first step. Extension of this system to enantioselective dibromination and its use in the synthesis of pentabromide stereoarrays relevant to bromosulfolipids is reported. The described dichlorination and dibromination reactions are capable of exerting diastereocontrol in complex settings allowing X-ray crystal structure analysis of natural and unnatural diastereomers of polyhalogenated stereohexads.

Catalytic chemo-, regio-, and enantioselective bromochlorination of allylic alcohols

Herein we describe a highly chemo-, regio-, and enantioselective bromochlorination reaction of allylic alcohols, employing readily available halogen sources and a simple Schiff base as the chiral catalyst. The application of this interhalogenation reaction to a variety of substrates, the rapid enantioselective synthesis of a bromochlorinated natural product, and preliminary extension of this chemistry to dibromination and dichlorination are reported.

Elimination of butylcycloheptylprodigiosin as a known natural product inspired by an evolutionary hypothesis for cyclic prodigiosin biosynthesis

The cyclic prodigiosins are an important family of bioactive natural products that continue to be the subject of numerous structural, synthetic, and biosynthetic studies. In particular, the structural assignments of the isomeric cyclic prodigiosins butylcycloheptylprodigiosin (BCHP) and streptorubin B have been the cause of significant confusion. Herein, we report detailed studies regarding the electron impact (EI) mass spectra of synthetic BCHP and streptorubin B that have allowed us to distinguish the two compounds in the absence of quality historical isolation NMR data. On the basis of these fragmentation differences, the status of BCHP as a natural product is challenged. The proposed mechanism of fragmentation is supported by the EI mass spectra of synthetic pentyl-chain analogues of BCHP and streptorubin B, X-ray crystallography, and DFT calculations. Elimination of BCHP from the prodigiosin family supports a proposed evolutionary hypothesis for the surprising biosynthesis of cyclic prodigiosins.

Catalytic enantioselective dibromination of allylic alcohols

A new dibromination reaction involving the combination of dibromomalonate as the bromonium source and a titanium bromide species as the bromide source has been developed. Enantioselective catalysis has been achieved through apparent ligand acceleration by a tartaric acid-derived diol.

Enantioselective total synthesis and confirmation of the absolute and relative stereochemistry of streptorubin B

The enantioselective total synthesis of the pyrrolophane natural product streptorubin B is described. Key steps in the concise route include the application of a one-pot enantioselective aldol cyclization/Wittig reaction and an anionic oxy-Cope rearrangement to forge the crucial 10-membered ring. Comparisons between CD spectra of synthetic and natural samples of streptorubin B coupled with X-ray crystallography allowed for the determination of the absolute stereochemistry of this natural product for the first time. These studies also provided unambiguous proof of the relative configuration between the butyl side chain and the bispyrrole subunit. Additional studies revealed a novel atropstereoselective Paal-Knorr pyrrole condensation and provided fundamental experimental insight into the barrier for atropisomerization of the natural product.

A synthesis of the carbocyclic core of maoecrystal V

An approach toward the synthesis of the complex polycyclic diterpene maoecrystal V (1) is described. Construction of the advanced tetracyclic core structure (i.e., 19) was achieved in 13 steps from 3,3-dimethylcyclohexanone (6) by employing a stereoselective Nazarov cyclization followed by a Diels-Alder reaction to forge the two contiguous quaternary stereocenters.

[Ischemic preconditioning inhibits ischemia/reperfusion induced myocardial apoptosis in rabbits in vivo]

OBJECTIVE

To investigate the effects of ischemic preconditioning on myocardial apoptosis induced by ischemia/reperfusion.

METHODS

Twenty four rabbits were randomly allocated to three groups(n = 8), pseudo-operation group(group P), ischemia/reperfusion group(group IR), and ischemic preconditioning group (group IP). Group IR and group IP were subjected to three hours of left anterior descending coronary artery occlusion followed by three hours of reperfusion. Ischemic preconditioning was achieved by three 5-minute cycles of ischemia, each followed by 5 minutes of reperfusion. Infarct size and area at risk were defined by dual staining with triphenyltetrazolium chloride and Evans blue dye. DNA laddering in the border zone myocardium of ischemic area at risk was revealed with agarose gel electrophoresis, and apoptosis index(AI) was obtained with flow cytometry.

RESULTS

Infarct size, expressed as a percentage of the area at risk(IS:AR), was(60.8 +/- 10.8)% in group IR. Ischemic preconditioning reduced myocardial infarct size significantly to (33.1 +/- 4.9)% (P < 0.05). AI was (13.83 +/- 3.98)% in group IR, and were reduced significantly to (5.85 +/- 1.59)% in group IP(P < 0.01). DNA laddering indicative of fragmented DNA was clearly demonstrated in myocardial specimens sampled from the lateral border zones of the ischemic area at risk in group IR but were attenuated in group IP.

CONCLUSION

It suggests that ischemic preconditioning inhibits the rabbit myocardial apoptosis induced by ischemia/reperfusion in vivo.

[Statistical analysis of 47 cases with Holt-Qram syndrome]

By statistical analysis of 47 cases with Holt-Qram syndrome(HOS), we found that the severity of the upper limb abnormalities and cardiac defects in HOS varied significantly with different individuals. The variations of appearance were related with the types and positions of mutatons of TBX5 gene which could damage the gene function and cause HOS. It is suggested that the genetic heterogeneity in HOS may be caused by the mutations of different genes.

[Advances in the expression of foreign genes in Hansenula polymorpha]

Hansenula polymorpha is a potential host for foreign gene expression, which has been applied widely in academic studying and industry application. It has a number of advantages of expressing genes derived from eukaryotic organisms, such as mitotically stable recombinant strains, faithful processing of the produced polypeptides, and high productivity et al. Numerous foreign proteins with high commercial value have been expressed successfully in H. polymorpha, among which some have been launched on the market. In this review, the favorable characteristics of this system for foreign gene production and new advances are described.

[Protective effects of sevoflurane pretreatment on myocardial ischemia-reperfusion injury in rabbits]

To observe the myocardial protective effects of sevoflurane pretreatment on ischemia-reperfusion injury, forty eight rabbits were divided into six groups randomly: control group, ischemia-preconditioning group, sevoflurane preconditioning group, ischemia preconditioning plus glyburide group, sevoflurane preconditioning plus glyburide group, glyburide group, each group subjected to three hours of left anterion descending coronary artery occlusion followed by three hours of reperfusion. Infarct size and area at risk were defined by staining. Infarct size [expressed as a percentage of the area at risk (IS:AR)] was (60.8 +/- 10.8)% in controls, and reduced to (33.1 +/- 4.9)% and (30.9 +/- 6.8)% respectively in ischemic preconditioning groups and sevoflurane preconditioning groups. Glyburide pretreatment eliminated the preconditioning effects of ischemia and sevoflurane [IS:AR = (59.3 +/- 11.2)% and (56.6 +/- 11.9)%, respectively; not significant]. Glyburide alone did not increase infarct size [IS:AR = (63.2 +/- 12.5)%, not significant]. It suggests that sevoflurane pretreatment protects the rabbit heart subjected to three hours of coronary occlusion from infarction.

Mutations in the gene encoding gap junction protein beta-3 associated with autosomal dominant hearing impairment

Hearing impairment is the most commonly occurring condition that affects the ability of humans to communicate. More than 50% of the cases of profound early-onset deafness are caused by genetic factors. Over 40 loci for non-syndromic deafness have been genetically mapped, and mutations in several genes have been shown to cause hearing loss. Mutations in the gene encoding connexin 26 (GJB2) cause both autosomal recessive and dominant forms of hearing impairment. To study the possible involvement of other members of the connexin family in hereditary hearing impairment, we cloned the gene (GJB3) encoding human gap junction protein beta-3 using homologous EST searching and nested PCR. GJB3 was mapped to human chromosome 1p33-p35. Mutation analysis revealed that a missense mutation and a nonsense mutation of GJB3 were associated with high-frequency hearing loss in two families. Moreover, expression of Gjb3 was identified in rat inner ear tissue by RT-PCR. These findings suggest that mutations in GJB3 may be responsible for bilateral high-frequency hearing impairment.

[Cytologic diagnosis of thyroid lesions by fine needle aspiration]

Fine needle aspiration cytology was used for the diagnosis of 1914 cases of thyroid lesions. In 365 cases, cytologic findings were compared with pathohistologic findings. 310 benign lesions including 272 tumors and 38 other lesions and 55 malignant tumors were noted. The total correspondence rate was 97% and the rate of misdiagnosis 3%. Sampling and diagnostic technics were discussed.