BACKGROUND:Osteosarcoma has a complex pathogenesis and a poor prognosis.While advancements in medical technology have led to some improvements in the 5-year survival rate,substantial progress in its treatment has not yet been achieved. OBJECTIVE:To screen key molecular markers in osteosarcoma,analyze their relationship with osteosarcoma treatment drugs,and explore the potential disease mechanisms of osteosarcoma at the molecular level. METHODS:GSE99671 and GSE284259(miRNA)datasets were obtained from the Gene Expression Omnibus database.Differential gene expression analysis and Weighted Gene Co-expression Network Analysis(WGCNA)on GSE99671 were performed.Functional enrichment analysis was conducted using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes separately for the differentially expressed genes and the module genes with the highest positive correlation to the disease.The intersection of these module genes and differentially expressed genes was taken as key genes.A Protein-Protein Interaction network was constructed,and correlation analysis on the key genes was performed using CytoScape software,and hub genes were identified.Hub genes were externally validated using the GSE28425 dataset and text validation was conducted.The drug sensitivity of hub genes was analyzed using the CellMiner database,with a threshold of absolute value of correlation coefficient|R|>0.3 and P<0.05. RESULTS AND CONCLUSION:(1)Differential gene expression analysis identified 529 differentially expressed genes,comprising 177 upregulated and 352 downregulated genes.WGCNA analysis yielded a total of 592 genes with the highest correlation to osteosarcoma.(2)Gene Ontology enrichment results indicated that the development of osteosarcoma may be associated with extracellular matrix,bone cell differentiation and development,human immune regulation,and collagen synthesis and degradation.Kyoto Encyclopedia of Genes and Genomes enrichment results showed the involvement of pathways such as PI3K-Akt signaling pathway,focal adhesion signaling pathway,and immune response in the onset of osteosarcoma.(3)The intersection analysis revealed a total of 59 key genes.Through Protein-Protein Interaction network analysis,8 hub genes were selected,which were LUM,PLOD1,PLOD2,MMP14,COL11A1,THBS2,LEPRE1,and TGFB1,all of which were upregulated.(4)External validation revealed significantly downregulated miRNAs that regulate the hub genes,with hsa-miR-144-3p and hsa-miR-150-5p showing the most significant downregulation.Text validation results demonstrated that the expression of hub genes was consistent with previous research.(5)Drug sensitivity analysis indicated a negative correlation between the activity of methotrexate,6-mercaptopurine,and pazopanib with the mRNA expression of PLOD1,PLOD2,and MMP14.Moreover,zoledronic acid and lapatinib showed a positive correlation with the mRNA expression of PLOD1,LUM,MMP14,PLOD2,and TGFB1.This suggests that zoledronic acid and lapatinib may be potential therapeutic drugs for osteosarcoma,but further validation is required through additional basic experiments and clinical studies.

Objective:To investigate whether the image quality of total-body PET/CT (TB PET/CT) with 1 min acquisition can meet the clinical diagnostic requirements.Methods:From May 2019 to September 2021, a total of 90 malignant tumor patients (60 males, 30 females, age 31-86 years) with primary lesions confirmed by pathological diagnosis in Zhongshan Hospital, Fudan University were respectively analyzed. All patients underwent conventional PET/CT (C PET/CT) scan with conventional clinical acquisition and TB PET/CT scan with 1 min acquisition after injecting 18F-FDG in random order. Paired t test or Wilcoxon signed rank test was used to analyze the image quality of these two scans. Results:SUV max of primary lesions in TB PET/CT group was significantly higher than that in C PET/CT group (15.9(7.9, 24.6) vs 12.5(5.8, 16.6); z=8.14, P<0.001), so were signal-to-noise ratio (SNR) of the blood pool, liver, muscles (9.3±3.0, 11.4(9.5, 14.2), 8.3(7.3, 10.1) vs 6.2±1.7, 9.4(7.7, 11.8), 6.0(4.9, 7.1)), tumor-to-blood pool ratio (TBR) (9.3(4.3, 14.8) vs 8.5(4.3, 11.1)), tumor-to-liver ratio (TLR) (6.7(3.0, 10.4) vs 6.1(2.9, 7.7)), tumor-to-muscle ratio (TMR) (23.2(11.5, 38.0) vs 18.3(9.6, 26.6); t=9.36, z values: 4.44-7.40, all P<0.001). Conclusion:The image quality of TB PET/CT scan with 1 min acquisition can meet the diagnostic requirements, and is better than the C PET/CT image quality with conventional clinical acquisition.

Objective:To investigate the clinical utility of 68Ga-labeled fibroblast activation protein inhibitor (FAPI) PET/CT in the detection of primary and metastatic gastric signet-ring cell carcinoma (GSRCC) and compared the results with those of 18F-FDG PET/CT. Methods:A total of 21 patients (10 males, 11 females, average age 52 years) with primary and metastatic GSRCC who underwent 68Ga-FAPI and 18F-FDG PET/CT at the First Affiliated Hospital of Xiamen University from June 2020 to May 2022 were retrospectively analyzed. Pathological results of surgery and (or) biopsy were used as the " gold standard" for final diagnosis. In cases whose surgery or tissue biopsies were not available, clinical and radiographic follow-up results were used as the reference standards. Wilcoxon signed-rank test was used to compare the SUV max of 18F-FDG and 68Ga-FAPI. McNemar χ2 test was used to compare the detection rate between 18F-FDG and 68Ga-FAPI PET/CT. Results:68Ga-FAPI PET/CT showed higher SUV max than 18F-FDG in primary tumors (5.3(2.4, 15.7) vs 2.4(1.8, 2.5); z=2.31, P=0.021), local recurrences (7.8(6.0, 8.9) vs 2.4(1.9, 3.4); z=2.20, P=0.028), lymph nodes metastases (7.7(4.5, 12.2) vs 2.4(1.9, 3.6); z=6.01, P<0.001) and bone/visceral metastases (6.7(5.3, 11.1) vs 2.4(2.0, 3.4); z=11.36, P<0.001). Regarding diagnostic accuracy, 68Ga-FAPI PET/CT showed higher sensitivities than 18F-FDG for primary tumors (7/9 vs 2/9; χ2=3.20, P=0.063) and local recurrences (7/7 vs 2/7; χ2=3.20, P=0.063). It also demonstrated higher lesion detection rates than 18F-FDG for suspicious lymph node metastases (86%(65/76) vs 32%(24/76); χ2=31.37, P<0.001) and bone/visceral metastases (99%(184/185) vs 39%(73/185); χ2=107.08, P<0.001). Conclusions:68Ga-FAPI PET/CT showed higher tumor uptake and lesion detection rate than 18F-FDG in the primary and metastatic GSRCC. 68Ga-FAPI PET/CT demonstrates good diagnostic performance for tumor detection, staging, and restaging of GSRCC, which is helpful to further guide clinical treatment strategy.

Objective:To develop a tetramer probe targeting fibroblast activation protein (FAP), named 1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetic acid (DOTA)-4P(FAP inhibitor (FAPI)) 4, evaluate its biodistribution and PET image in FAP-positive-tumor bearing nude mice, and explore its feasibility as a novel radio-regent for treatment of FAP-positive tumor. Methods:FAP tetramer probe was constructed on the FAPI-46 motif with four mini-polyethylene glycol (PEG)(PEG 3) spacers between the four FAPI motifs, denoted as 4P(FAPI) 4. DOTA was used as the chelator for radiolabeling with 68Ga and 177Lu. The FAP binding characteristics were test by in vitro cell competitive binding experiment. Small-animal PET, in vivo biodistribution, and radionuclide targeting therapy were performed in HT-1080-FAP tumor bearing nude mice ( n=39). Independent-sample t test was performed to analyze tumor uptake data, and two-factor repeated measures analysis of variance was utilized to compare tumor volume data in radioactive isotope therapy. Results:Cell experiment showed that FAPI-tetramer and FAPI-monomer had similar half maximal inhibitory concentration values (3.29 and 2.15 nmol/L). 68Ga/ 177Lu radiolabeled FAPI-tetramer had better tumor uptake and retention than FAPI-monomer in small-animal PET and in vivo biodistribution experiment, with the tumor uptake for 177Lu-DOTA-4P(FAPI) 4 and 177Lu-FAPI-46 at 48 h of (18.72±1.32) vs (2.72±1.20) percentage activity of injection dose per gram of tissue (%ID/g) ( t=15.55, P<0.001). 177Lu-DOTA-4P(FAPI) 4 group showed best anti-tumor efficacy compared with 177Lu-FAPI-46 and control group in radionuclide targeting therapy. On the 2nd day after the start of treatment, the tumor volume in the tetramer treatment group was significantly smaller than that in the control group (mean difference 67.19 mm 3, P=0.049); on the 14th day after the start of treatment, the tumor volume in the tetramer treatment group was significantly smaller than that in the monomer treatment group (mean difference 414.33 mm 3, P=0.005). Conclusion:FAPI-tetramer can improve tumor uptake and retention ability compared with FAPI-46, and 177Lu-DOTA-4P(FAPI) 4 can be a promising radio-agent for FAP-positive tumor therapy.

Background/Aims: Epstein-Barr virus-associated gastric cancers (EBVaGCs) have unique molecular and clinicopathological characteristics. The cyclic GMP-AMP synthase-stimulator of interferon genes (STING) pathway is recently recognized as the critical innate immunity against pathogens and tumors. STING is also a master regulator in the cancer-immunity cycle and targeting STING could synergize with existing immune-checkpoint therapies. However, the role of STING in GC, especially in EBVaGC, and its correlation with programmed death-ligand 1 (PD-L1) remain largely unclear. Methods: We collected 78 cases of EBVaGCs and 210 cases of EBV-negative GC (EBVnGC) from a total of 1,443 cases of GC analyzed by EBV-encoded small RNA in situ hybridization. We investigated STING and PD-L1 expression and their concomitant prognostic value in EBVaGCs and EBVnGCs using tissue microarray and immunohistochemistry. The effects of STING and PD-L1 expression on the overall survival of patients with EBVaGC or EBVnGC were assessed by univariate and multivariate analysis. Results: We found that both STING and PD-L1 exhibited significantly higher expression in the EBVaGCs than that in the EBVnGCs. The expression of STING was positively correlated with that of PD-L1 in EBVaGCs. Simultaneous negative expression of STING and PD-L1, and positive expression of STING were independent prognostic risk factors for EBVaGC and EBVnGC, respectively. Conclusions This is the first prognostic retrospective study of STING and PD-L1 expression and the prognosis among EBVaGC and EBVnGC. The expression and prognostic value of STING and PD-L1 are different in the two types of GCs. STING and PD-L1 are promising prognostic biomarkers and therapeutic targets for EBVaGC and EBVnGC.

Blast injury of the chest injury is the most common wound in modern war trauma and terrorist attacks, and is also the most fatal type of whole body explosion injury. Most patients with severe blast injury of the chest die in the early stage before hospitalization or during transportation, so first aid is critically important. At present, there exist widespread problems such as non-standard treatment and large difference in curative effect, while there lacks clinical treatment standards for blast injury of the chest. According to the principles of scientificity, practicality and advancement, the Trauma Society of Chinese Medical Association has formulated the guidance of classification, pre-hospital first aid, in-hospital treatment and major injury management strategies for blast injury of the chest, aiming to provide reference for clinical diagnosis and treatment.

Objective: To compare the effects of indirect reduction, percutaneous anterior posterior screw and direct reduction, posterior anterior screw in the treatment of posterior malleolus fracture. Methods: A retrospective analysis was made on 58 patients with posterior malleolus fracture treated by cannulated screw fixation from January 2013 to December 2017 in the Department of Orthopedics, Affiliated Hospital of Guangdong Medical University.They were divided into anterior and posterior screw group (26 cases) and posterior and anterior screw group (32 cases) according to different treatment methods.The incidence of poor screw position and other complications were compared between the two groups.Health status and ankle function at the last follow-up were compared between the two groups. Results: The incidence of screw malposition in the anterior and posterior screw fixation group was 23.08%(6/26), which was significantly higher than that in the posterior screw fixation group was 3.85%(1/32). The difference between the two groups has statistically significant (χ²=5.381, P=0.020); there was no significant difference in other complications such as infection, traumatic arthritis, bone nonunion (all P>0.05). At the last follow-up, the OMA scores of AP group were (80.70±8.16)and PA group were(75.23±9.33), There were significant differences between the two scores(t=2.240, P=0.029), the AOFAS scores of AP group were (80.57±7.25) and PA group were(75.38±10.19), There were significant differences between the two scores(t=2.110, P=0.039). Conclusion The Indirect reduction and percutaneous anterior and posterior screw treatment have a high incidence of malposition of the screw, which has an impact on ankle function.Direct reduction and posterior and anterior screw fixation can significantly reduce the incidence of malposition of the screw and obtain better functional results.

Objective:To develop a novel α vβ 3-targeted theranostic agent 177Lu-Evans blue (EB)-Arg-Gly-Asp (RGD) and evaluate its value for SPECT imaging and targeted radionuclide therapy in the non-small cell lung cancer (NSCLC)-patient-derived xenografts (PDX). Methods:The α vβ 3-targeted molecule RGD was conjugated with the albumin binding moiety EB to obtain EB-RGD, and EB-RGD was further conjugated with the chelator 1, 4, 7, 10-tetraazacyclododecane-1, 4, 7, 10-tetraacetic acid (DOTA) for 177Lu radiolabeling. NSCLC-PDX mice models ( n=68) were established. 177Lu-EB-RGD SPECT imaging, biodistribution study were performed in 28 PDX mice models after being injected with 177Lu-EB-RGD or 177Lu-RGD. Targeted radionuclide therapy were subsequently performed in NSCLC-PDX mice models, saline group (group A), 18.5 MBq 177Lu-RGD group (group B), 18.5 MBq 177Lu-EB-RGD group (group C), 29.6 MBq 177Lu-EB-RGD group (group D), n=10 in each group; tumor volumes of PDX mice models in each group were observed within 50 d. Differences between 2 groups were compared using independent-sample t test. Results:177Lu-EB-RGD was radiolabeled at a specific activity of (55±14) GBq/μmol, with a radiochemical yield of more than 95% and a radiochemical purity of more than 95%. Regarding the SPECT imaging, tumors in NSCLC-PDX mice were clearly observed from 4 to 96 h post-injection and the tumor to muscle ratio (T/M) reached 7.34±0.67, 14.63±3.82, 15.69±3.58 and 15.99±5.42 at 4, 24, 72, 96 h post-injection, respectively. Biodistribution study further confirmed the findings from SPECT imaging, and the tumor uptake of 177Lu-EB-RGD were markedly increased compared to 177Lu-RGD 4 h post-injection ((10.15±1.17) vs (3.30±1.47) percent injection dose per gram (%ID/g); t=18.60, P<0.05). Regarding targeted radiotherapy, the tumor volumes were quickly increased within 50 d after treatment in group A and B, while the tumor volumes were decreased in group C and D, until the tumors in group C and D disappeared at the 28th day after initial treatment with no sign of recurrence during the observation period. Conclusions:177Lu-EB-RGD can target α vβ 3-positive NSCLC-PDX with intense tumor to background ratio and strong tumor inhibition efficacy. The preclinical data suggests that 177Lu-EB-RGD may be an effective new treatment option for advanced NSCLC patients with resistance or ineffective results for targeted therapy.

Objective:To investigate the therapeutic efficacy and potential mechanisms of integrin α vβ 3-targeted radionuclide therapy (TRT) in combination with anti-programmed cell death protein ligand 1 (PD-L1) immunotherapy. Methods:Integrin α vβ 3-targeted molecule Arg-Gly-Asp (RGD) was conjugated with Evans blue (EB) and then labeled with 177Lu to obtain 177Lu-EB-RGD. The radioactivity and radiochemical purity were determined. MicroSPECT imaging, biodistribution, and in vivo therapeutic efficacy were subsequently performed in MC38 murine colon cancer models. Volume of tumor and body mass of mice were observed to assess the therapeutic efficacy and safety ( n=9 in each group). Flow cytometry was used to evaluate therapy response of saline-treated (control, group A), 18.5 MBq 177Lu-EB-RGD-treated (group B), 10 mg/kg PD-L1 antibody-treated (group C), TRT combined with immunotherapy-treated (group D, 18.5 MBq 177Lu-EB-RGD and 10 mg/kg PD-L1 antibody) mice and alterations in tumor microenvironment (PD-L1 + immune cells, CD8 + T cells and regulatory T cells). Independent-sample t test and repeated measures analysis of variance were used for data analysis. Results:The radioactivity of 177Lu-EB-RGD was (55.85±14.00) GBq/μmol. SPECT imaging clearly visualized the MC38 tumors in mice models with high uptake and long retention time, the tumor/muscle ratio reached 14.87±0.88 at 24 h postinjection, while less uptake and retention in normal tissues. Tumor uptake of 177Lu-EB-RGD was significantly higher than that of 177Lu-RGD 4 h post-injection ((12.00±1.60) vs (3.69±0.37) %ID/g; t=8.63, P<0.01). The efficacy results between each treatment group was significantly different ( F=7.32, P=0.03) at day 6 post-treatment. The combination therapy showed the most outstanding anti-tumor efficacy with 7/9 mice showed complete response. Flow cytometry results showed that TRT up-regulated the PD-L1 expression significantly, namely, PD-L1 + immune cells in group B and group A were significantly different (CD45 + /PD-L1: 2.34% vs 0.95%, CD11b + /PD-L1: 2.41% vs 0.66%; t values: 11.17 and 8.70, both P<0.01); immunotherapy and combination therapy dramatically stimulated the infiltration of CD8 + T cells (2.07% vs 0.26%, 2.71% vs 0.26%; t values: 4.10 and 6.03, both P<0.05). Conclusion:TRT in combination with immunotherapy synergistically enhance anti-tumor efficacy, which is expected to play a role in the treatment of patients with advanced tumor where TRT can be applied.

Objective:To explore the imaging features of 18F-fluorodeoxyglucose (FDG) PET/CT (high-resolution CT, HRCT) imaging in focal organizing pneumonia (FOP). Methods:Patients with solid nodular FOP ( n=45; 33 males, 12 females, age (58±9) years) and early peripheral non-mucinous solid lung adenocarcinoma ( n=47; 21 males, 26 females, age (63±10) years) confirmed by postsurgical pathology between May 2012 and December 2018 in Zhongshan Hospital, Fudan University were retrospectively analyzed. All patients underwent 18F-FDG PET/CT (HRCT) imaging followed by surgery within 3 weeks. The imaging findings and characteristics of the lesions were recorded. Differences of the maximum standardized uptake value (SUV max) and maximum diameter between FOP and adenocarcinoma were analyzed by Mann-Whitney U test or t′ test. Spearman correlation or Pearson correlation analysis was performed to analyze the relation between SUV max and maximum diameter. Binary logistic regression analysis was performed to identify the predictive factors for FOP. Finally, the receiver operating characteristic (ROC) curve analysis was used for evaluation of diagnostic efficiency. Results:The SUV max of FOP was lower than that of lung adenocarcinoma (3.1(1.7, 4.9) vs 6.5(3.8, 9.3); z=-4.598, P<0.01), and the maximum diameter of FOP was smaller than that of lung adenocarcinoma ((18.0±6.3) mm vs (21.8±4.3) mm; t′=-3.424, P<0.01). The SUV max was positively correlated with the maximum diameter in FOP group ( r s=0.509, P<0.01), while the SUV max of lung adenocarcinoma was not correlated with the lesion size ( r=0.076, P>0.05). HRCT of the PET/CT system showed the fusiform shape were more common in FOP ( χ2=9.549, P<0.05). Multivariate regression analysis identified that SUV max≤7.1, diameter≤18.3 mm, and fusiform shape were independent factors to predict FOP, with odds ratio ( OR) of 10.585, 4.674, 9.073, respectively (all P<0.05). ROC curve analysis showed that the area under the curve (AUC) of SUV max≤7.1 combined with diameter≤18.3 mm and fusiform nodule was 0.860, and the sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 97.8%(44/45), 70.2%(33/47), 75.9%(44/58), 97.1%(33/34), and 83.7%(77/92), respectively. Conclusion:SUV max≤ 7.1 combined with maximum diameter≤ 18.3 mm and fusiform shape may predict solid nodular FOP.