PI3Kγ and PI3Kδ have important regulatory roles in the immune system, and targeting these two subtypes helps to reshape the tumor microenvironment. PI3Kγ and PI3Kδ are potential targets for tumor immunotherapy. In this study, a series of new pyrazolopyrimidine derivatives were designed and synthesized on the basis of our previously reported PI3K inhibitors, resulting in the discovery of compound 16l as a potent and selective PI3Kγ/δ dual inhibitor. Compound 16l demonstrated strong biochemical potencies against PI3Kγ and PI3Kδ with IC₅₀ values of 0.11 and 0.79 nmol·L^-1. In cell-based assays, it potently inhibited the PI3Kγ and PI3Kδ mediated Akt S473 phosphorylation with EC₅₀ values of 3 and 7 nmol·L^-1. In vivo, compound 16l exhibited acceptable pharmacokinetic properties in Sprague-Dawley (SD) rats and suppressed the tumor growth in a MC38 syngeneic mouse model. The animal experiments were approved by the Animal Ethics Committee of Hefei Institutes of Physical Science, Chinese Academy of Sciences (approval number: DWLL-2000-06). In addition, no appreciable human ether-a-go-go-related gene (hERG) inhibition was observed for compound 16l even at 30 μmol·L^-1. These results suggested that compound 16l might be a potential research tool for studying the PI3Kγ/δ mediated signaling pathways.

DNA polymerase theta (Polθ), also known as DNA polymerase θ, is the member of the DNA polymerase A family and plays a crucial role in the repair of DNA double-strand breaks (DSB). Polθ has 3 distinct structural domains: the N-terminal helicase-like domain with a conserved sequence, the C-terminal polymerase domain, and the central domain, which is a disordered sequence connecting these two regions. Notably, Polθ is the only known polymerase in eukaryotes that possesses helicase activity. However, it is also an error-prone polymerase. When DNA DSBs occur, a specialized network consisting of at least 4 pathways, including classical-non homologous end joining (C-NHEJ), homologous recombination (HR), single-strand annealing (SSA), and alternative-end joining (Alt-EJ), is responsible for repairing DNA damage caused by DSBs. In the absence of major DNA repair pathways like HR, cells rely on Alt-EJ pathway mediated by Polθ to repair damaged DNA and maintain genomic stability. Nevertheless, due to the low fidelity of Polθ, Alt-EJ repair often leads to errors. Depletion of Polθ has shown to increases DSB formation and compromise genomic stability. Conversely, overexpression of Polθ has been associated with increases DNA damage markers and impairs cell cycle progression. As a result, the impact of Polθ on genome stability remains controversial. Furthermore, overexpression of Polθ is frequently observed in cancer and is associated with a characteristic mutational signature and poor prognosis. Depleting Polθ in an HR-deficient background has been shown to impair cell viability, suggesting a synthetic lethal (SL) relationship between Polθ and HR factors. In recent years, targeted chemotherapy drugs that inhibit tumor growth have gained significant attention. However, off-target effects and drug resistance pose challenges for clinical application, particularly with poly-ADP-ribose polymerase inhibitor (PARPi). Blocking Polθ activity in HR-deficient tumor cells has been found to reverse PARPi resistance, making Polθ a very promising therapeutic target in cancer treatment. The availability of crystal structures for both helicase and polymerase domain has facilitated the design of potent inhibitors of Polθ. Currently, several highly specific and effective small molecule inhibitors targeting Polθ, such as Novobiocin, RP-6685, and ART558, have been reported to effectively block various cancers with HR deficiency. The initial success of these inhibitors points to new directions for treating BRCA1/2-mutated tumors. Additionally, reducing the Alt-EJ repair pathway mediated by Polθ can improve HR repair efficiency and increase the chance of exogenous gene target integration (TI), suggesting potential new applications for Polθ inhibitors. This article reviews the recent research progress on the molecular function of Polθ and its involvement in the Alt-EJ pathway modification mechanism, providing insights for a deeper understanding of this field.

Objective To analyze the changes of B lymphocyte(B cells)subsets in peripheral blood of patients with chronic hepatitis B(CHB)and to explore its clinical significance.Methods Peripheral blood samples were collected from 37 treatment-na?ve CHB patients who were admitted to the Fifth Medical Center of PLA General Hospital from July 2022 to October 2022,and peripheral blood samples collected from 18 healthy individuals who have received the hepatitis B vaccine as healthy controls(HC).The study subjects'clinical indexes such as age,HBV DNA viral load,HBsAg quantification,HBeAg semi quantification,ALT,AST,and AST/ALT ratio were collected.The change characteristics of the frequency,phenotypic and functional markers of peripheral blood B lymphocytes and their subsets were compared between CHB and HC.Using multi-color flow cytometry,and the correlation between them and clinical indexes was analyzed.Results Frequency analysis of each subset of B cells showed that compared with HC,the frequency of total B cells,transitional B cells and naive B cells was decreased(P<0.05),while the frequency of mature B cells,memory B cells,atypical memory B cells and activated memory B cells was increased in CHB patients(P<0.01).And there was no significant difference in the frequency of resting memory B cells between the two groups(P>0.05).The results of functional analysis showed that compared with HC,the expression levels of CD79b on total B cells,mature B cells,memory B cells,naive B cells,activated memory B cells,atypical memory B cells and resting memory B cells in CHB patients were increased(P<0.05).The expression level of programmed cell death protein-1(PD-1)on atypical memory B cells in CHB patients was also higher than that in HC group(P<0.05).The results of correlation analysis showed that the frequency of total B cells in CHB patients was slightly negatively correlated with age(r=-0.39,P<0.05),while the expression of programmed death-1(PD-1)on total B cells,mature B cells,transitional B cells,memory B cells and naive B cells were slightly positively correlated with age(r>0.36,P<0.05).Conclusions Chronic HBV infection leads to depletion of the frequency and function of a portion of B cells in the peripheral blood of CHB patients,and age is a potential risk factor for the decline in humoral immune function in CHB patients.

Objective To investigate the effect of artemisinin(ART)on the malignant biological behavior of colorectal cancer(CRC)cells stimulated by glucose and its mechanism.Methods The concentration gradients of 0,5,10,20,40 and 60 μmol/L of ART were used to treat the human colorectal cancer cell line SW480,and then the cell viability was detected by CCK-8.Cell apoptosis was detected by flow cytometry.Transwell was used to detect the cell migration and invasion.Western blot was used to detect the apoptosis,epithelial-mesenchymal transition(EMT)and Janus kinase 2(JAK2)/signal transducer and activator of transcription 3(STAT3)related proteins expression.Results Compared with the 0 μmol/L of ART,the viability of SW480 cells decreased under 5,10,20,40,60 μmol/L of ART treatment(P<0.05),and IC50 was 36.91 μmol/L.Therefore,the cells treated with 10,20 and 40 μmol/L of ART were as the low-dose,medium-dose and high-dose ART groups,the cells treated with 0 μmol/L of ART were as the control group,and the cells treated with 40 μmol/L of ART and 10 μmol/L of Coumermycin A1 were as the Coumermycin A1 group.Compared with the control group,the cell scratch wound healing rate,invasion ability,and expression levels of Bcl-2,N-cadherin,Vimentin,p-JAK2,and p-STAT3 in the low-dose ART group,the medium-dose ART group,and the high-dose ART group decreased obviously(P<0.05),while the apoptosis rate,and expression levels of Bax,Caspase-3 and E-cadherin increased(P<0.05).Compared with the high-dose ART group,the cell scratch wound healing rate,invasion ability,and expression levels of Bcl-2,N-cadherin,Vimentin,p-JAK2,and p-STAT3 in the Coumermycin A1 group increased obviously(P<0.05),while the apoptosis rate,and expression levels of Bax,Caspase-3 and E-cadherin decreased(P<0.05).Conclusion ART may inhibit the viability,migration,invasion and EMT of glucose-stimulated CRC cells and promote apoptosis by inhibiting the JAK2/STAT3 signaling pathway.

To clone and express the K26 gene of Leishmania isolated from three types of visceral leishmaniasis epidemic ar-eas in China and evaluate its effect on detecting specific antibodies against visceral leishmaniasis.The K26 fragments from Leishmania isolated KS-6,SC6 and JIASHI-1 was synthesized and cloned into pET32a vector.The recombinant plasmid pET32a-K26 was transformed into Escherichia coli BL21 strains and induced by isopropyl-β-D-thiogalactopyranoside(IPTG).The expressed recombinant protein was purified by the His-tagged affinity column(Ni-NTA).Serum samples of 110 visceral leishmaniasis patients were used for evaluating the sensitivity by ELISA.Serum samples from patients with malaria,schisto-somiasis japonica,cystechinococcosis,toxoplasmosis,paragon-imiasis,clonorchiosis and 40 healthy people were used for eval-uating the specificity.Detection results of ELISA were compared with that of rK39 strip of American InBios company.Comparation among three K26 antigens were given by x2 test.The sensitivity of the recombinant K26 protein of KS-6,SC6 and JIASHI-5 strains of Leishmania and rK39 strip test to detect the sera of patients with visceral leishmaniasis was 90.00％(99/110),92.73％(102/110),90.91％(100/110)and 93.64％(103/110),respectively.There was no cross reactivity with malaria(10),schistosomiasis japonica(10),cystechinococcosis(10),toxoplasmosis(5),paragonimiasis(5)and clonorchiosis(5),and 40 sera from healthy people were also negative.The specificity was 100.00％.There was no statistical difference in the sensitivity of the recombinant K26 protein of KS-6,SC6 and JIASHI-1 strains of Leishmania and rK39 strip test,x2 values are 0.97,0.07 and 0.57 respectively and the P values are 0.33,0.79 and 0.45,respectively.There was no statis-tical difference in the sensitivity of three K26 antigens(x2=0.53,P=0.97).Conclusion The recombinant K26 antigen has po-tential application value in the diagnosis of visceral leishmaniasis.

Objective:To analyze the type and distribution characteristics of irregular antibodies in 71847 hospitalized patients who prepared to accept blood transfusion,and to explore their role in safe blood transfusion. Methods:71847 patients who applied for red blood transfusion from January 2020 to October 2023 were selected.All specimens were screened and identified for the irregular antibody by microcolumn gel antiglobulin technique.Results:Among the 71847 patients preparing for accept blood transfusion,301 cases tested positive for irregular antibodies (0.42％).Of these 301 antibody-positive patients,252 (83.72％)exhibited alloantibodies.The Rh blood group system was the most common,accounting for 179 cases (59.47％).Antibodies in Rh blood group system included anti-E (135,44.85％),anti-E+c (24,7.97％),anti-C+e (10,3.32％),anti-c (6,1.99％),anti-D (3,1.00％),and anti-D+C (1,0.33％).By analyzing 301 cases with irregular antibodies,it found the positive rate of>60 years old group was higher than that in≤60 years old (0.61％vs 0.33％),female group was higher than that in male group (0.50％ vs 0.31％),internal medicine and gynaecology and obstetrics groups were both higher than that in surgery group (1.25％ vs 0.20％;0.32％ vs 0.20％),group with pregnancy/transfusion history was higher than that in non-pregnancy/transfusion history (0.64％ vs 0.13％),the differences were statistically significant (P<0.05). Conclusion:In the routine monitoring of the blood group,it is necessary to detect RhE,so as to reduce the positive rate of irregular antibodies greatly and further ensure the safety of blood transfusion.

Objective To evaluate the bioequivalence of a single oral dose of ritonavir in fasted and fed conditions in healthy Chinese adult subjects with the test and reference formulations.Methods A single-center,open-label,randomized,single-dose,two-periods,two-sequence crossover design was used,and 64 subjects were enrolled in both the fasted and fed groups.The subjects received 100 mg of the test preparation or reference preparation orally per cycle,and the drug concentration of ritonavir in plasma was detected using the high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)method.Pharmacokinetic parameters were estimated by a non-compartment model,and SAS 9.4 software was used for statistical analysis.Results Arithmetic mean values of the main pharmacokinetic parameters of the subject formulation of ritonavir tablets and the reference formulation in the fasting group:Cmax were(791.90±400.20)and(809.60±449.14)ng·mL-1;AUC0_t were(6 072.61±2 631.98)and(6 296.30±3 388.95)ng·h·mL-1;AUC0-∞ were(6 129.59±2 655.57)and(6 347.26±3 434.12)ng·h·mL-1,respectively.Arithmetic mean values of the main pharmacokinetic parameters of the subject formulation of ritonavir tablets and the reference formulation in the fed group:Cmax were(512.37±233.60)and(521.74±223.87)ng·mL-1;AUC0_t were(4 203.43±2 221.33)and(4 200.13±1 993.50)ng·h·mL-1;AUC0_∞ were(4 259.21±2 266.88)and(4 259.63±2 044.12)ng·h·mL-1.The 90％confidence intervals for the geometric mean ratios of Cmax,AUC0_t and AUC0_∞ of the prototype drug ritonavir in plasma after oral administration of 100 mg of the test and reference formulations of ritonavir tablets under fasting and fed conditions fell within the 80.00％to 125.00％equivalence interval.Conclusion The test and reference formulations of ritonavir tablets were bioequivalent under fasting and postprandial conditions.

Background/Aims: Chronic hepatitis C (CHC) patients who failed antiviral therapy are at increased risk for hepatocellular carcinoma (HCC). This study assessed the potential role of metformin and statins, medications for diabetes mellitus (DM) and hyperlipidemia (HLP), in reducing HCC risk among these patients. Methods: We included CHC patients from the T-COACH study who failed antiviral therapy. We tracked the onset of HCC 1.5 years post-therapy by linking to Taiwan’s cancer registry data from 2003 to 2019. We accounted for death and liver transplantation as competing risks and employed Gray’s cumulative incidence and Cox subdistribution hazards models to analyze HCC development. Results: Out of 2,779 patients, 480 (17.3%) developed HCC post-therapy. DM patients not using metformin had a 51% increased risk of HCC compared to non-DM patients, while HLP patients on statins had a 50% reduced risk compared to those without HLP. The 5-year HCC incidence was significantly higher for metformin non-users (16.5%) versus non-DM patients (11.3%; adjusted sub-distribution hazard ratio [aSHR]=1.51; P=0.007) and metformin users (3.1%; aSHR=1.59; P=0.022). Statin use in HLP patients correlated with a lower HCC risk (3.8%) compared to non-HLP patients (12.5%; aSHR=0.50; P<0.001). Notably, the increased HCC risk associated with non-use of metformin was primarily seen in non-cirrhotic patients, whereas statins decreased HCC risk in both cirrhotic and non-cirrhotic patients. Conclusions Metformin and statins may have a chemopreventive effect against HCC in CHC patients who failed antiviral therapy. These results support the need for personalized preventive strategies in managing HCC risk.

With the development of small-molecule immunotherapy drugs, its combination with the programmed cell death ligand 1/programmed cell death protein 1 (PD-L1/PD-1) antibodies would provide a new opportunity for cancer treatment. Therefore, targeting PD-L1/PD-1 axis by small-molecule drug is an attractive approach to enhance antitumor immunity and considered as the next generation of tumor immunotherapy. In the present study, we investigated the anti-tumor role of salvianolic acid B (SAB) by regulating the PD-L1 level in tumors. Changes of total PD-L1 and membrane PD-L1 levels were determined by Western blot, flow cytometry and PD-1/PD-L1 interaction assays. The expression of mRNA level of PD-L1 was detected by real-time PCR. The cytotoxicity of activated peripheral blood mononuclear cell (PBMC) cells toward co-cultured tumor cells was measured by cell impedance assay and crystal violet experiment. Surface plasma resonance technique was used to analyze the direct interaction between SAB and ubiquitin carboxyl-terminal hydrolase 2 (USP2). The antitumor effect of SAB in vivo was examined by C57BL/6 mice bearing MC38 xenograft tumor (all animal experiments were conducted in accordance with the Animal Ethics Committee of the Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences). Western blot and flow cytometry assay showed that SAB can significantly downregulate the abundance of PD-L1 in RKO and PC3 cells in dose- and time-dependent manner. PD-1/PD-L1 binding assay revealed that SAB reduces the binding of tumor cells to recombinant PD-1 protein. Mechanism studies revealed that SAB can bind directly to USP2 protein and inhibit its activity, thus promote the ubiquitin-proteasome pathway degradation of PD-L1 proteins. In addition, Cell impedance and crystal violet staining indicated that SAB enhances the killing activity of co-cultured PBMC cells toward tumor cells. MC38 tumor transplanted mouse experiments revealed that SAB treatment displayed significant suppression in the growth of MC38 tumor xenografts in C57BL/6 mice with an inhibition rate of 63.2% at 20 mg·kg^-1. Our results demonstrate that SAB exerts its anti-tumor activity by direct binding and inhibiting the activity of USP2 and reducing the PD-L1 level. Our study provides an important material basis and scientific basis for the potential application of SAB in tumor immunotherapy drug targeting USP2-PD-L1 axis.

Abstract: Objective　To evaluate the potential transmission risk of schistosomiasis in Yunnan Province, and to provide strategic basis for the prevention and control. Methods　Based on the prevalence of schistosomiasis, the social and environmental factors that may lead to the epidemic, 1-3 villages from 3 provincial-level and 15 county-level counties (cities and districts) were selected as the evaluated villages in 2021. The risk of schistosomiasis spread was analyzed comprehensively by consulting, reviewing and collecting routine surveillance data of schistosomiasis in the villages, combined with snail and wild feces survey. The risk level was evaluated for the positive snails, positive wild feces, resident infection, average density of live snails and snail frame occurrence rate. Results　Totally 7 snail counties schistosomiasis transmission was blocked of 18 epidemic counties and the rest were eliminated counties. A total of 152 447 snail frames were investigated and 3 043 frames with snails, 15 895 snails were captured and included 15 727 live snails in the 32 evaluated villages. The total area of snail was 58.87 hm2 and the area of reoccurrence was 34.19 hm2 with snail frame occurrence rate of 2.00% and average density of live snails 0.103 2/0.11 m2, and no positive snails were found by loop-mediated isothermal amplification (LAMP) assay. A total of 1 374 wild feces were collected in 27 evaluated villages of 14 epidemic counties, mainly from cattle, dogs, sheep, equine animals, pigs and so on, all of which were negative. According to the risk assessment of epidemic spread, Yongle Village and Yongsheng Village in Eryuan County, Zhiming Village in Chuxiong City were Ⅱ risk, and the rest were Ⅲ risk. Conclusions　Although the risk of transmission is low in Yunnan Province, the risk of transmission and spread still exists. It is necessary to strengthen the risk monitoring, control of snail and effective management of livestock to prevent the rebound of the epidemic.