Objective To screen the targets related to the metabolic enzymes involved in the cholesterol synthesis pathway that inhibits the polarization of macrophages towards M1 phenotype,and verify the intervention effects and underlying mechanisms in colorectal cancer cells.Methods Mouse colorectal cancer MC38 cells were divided into control group(si-NC)and experimental groups(the expression of enzymes in cholesterol synthesis pathway was interfered with siRNA for corresponding targets).RT-qPCR was used to detect the mRNA levels of corresponding targets in MC38 cells after transfection.After peritoneal macrophages were extracted from male C57BL/6 mice(6 weeks old,weighing 13～18 g),the macrophages were then treated with the conditioned media of MC38 cells transfected with different siRNAs for 48 h.RT-qPCR was employed to detect the mRNA levels of IL-1β,IL-6 and TNF-α in the macrophages so as to evaluate the effect of the culture media on the M1 polarization.MC38 cells were divided into control groups(OE-NC and sh-NC),farnesyl-diphosphate farnesyltransferase 1(FDFT1)overexpression group(OE-FDFT1)and FDFT1 knockdown group(sh-FDFT1).RT-qPCR was applied to detect the mRNA expression of FDFT1,and Western blotting was conducted to measure the protein level of FDFT1.C57BL/6 mice were subjected randomly to construct a subcutaneous tumor-bearing model and a model of intraperitoneal metastatic tumor(n=5)respectively.The growth of tumor mass was then measured.Flow cytometry was used to observe the proliferation and apoptosis of MC38 cells,and Trans well assay to detect migration ability of MC38 cells.Five C57BL/6 macrophage-depleted mice(established with injection of clodronate liposome suspension through tail vein)received intraperitoneal implantation to construct a metastasis model,and then the obtained tumor masses were then weighted.Results Compared with MC38 cells after si-NC transfection,the mRNA levels of corresponding targets in MC38 cells in the experimental groups were significantly reduced(P＜0.05).Significant increases were found in the mRNA levels of IL-1β,IL-6 and TNF-α of the macrophages with FDFT1 interference than the control cells(P＜0.05).There were no statistical differences in the proliferation,apoptosis and migration of MC38 cells in the control group(OE-NC and sh-NC)and the cells of the FDFT1 overexpression group and FDFT1 knockdown group(P＞0.05).In both the subcutaneous tumor-bearing model and the model of intraperitoneal metastatic tumor,the mass weight was significantly heavier in the OE-FDFT1 group than the OE-NC group(P＜0.01),and was notably smaller in the sh-FDFT1 group than the sh-NC group(P＜0.01).For the macrophage-depleted mouse tumor model,no remarkable change was observed in the tumor weight between the OE-FDFT1 group and the OE-NC group as well as the sh-FDFT1 group and the sh-NC group.Conclusion FDFT1,the metabolic enzyme in the cholesterol synthesis pathway of colorectal cancer tumor cells,is a potential target for tumor immunotherapy targeting macrophages,which promotes tumor progression by regulating macrophages.

Objective:This study evaluates the performance of chemiluminescence assay, which is designed to detect Hepatitis D Virus (HDV) Immunoglobulin G (IgG) antibodies.Methods:A comparative analysis was conducted among chemiluminescence anti-HDV IgG reagent, the magnetic particle-based domestic reagent A and domestic reagent B, and the Robo Gene HDV RNA kit, using 1909 HBsAg-positive plasma samples. This comparison aimed to delineate clinical specificity and detection accuracy. The anti-HDV IgG reagent precision was assessed at three different concentration levels following the Clinical Laboratory Standards Institute EP5-A2 guidelines. The specificity of the assay was validated using 200 HAV IgM positive, 545 HBsAg-positive but anti-HDV IgG-negative, 350 anti HCV positive plasma samples and 200 healthy human blood samples. Additionally, a concordance study was conducted with 545 HBsAg-positive and 37 anti-HDV IgG-positive plasma samples, comparing the anti-HDV IgG reagent against reagent A.Results:1 909 HBsAg-positive plasma samples were tested using 3 anti HDV IgG reagent and 1 HDV RNA reagent, 19 samples were identified as anti-HDV IgG-positive. The anti-HDV IgG demonstrated superior accuracy and specificity. The assay exhibited excellent precision, with intra-assay coefficient of variation (CV) values ranging from 1.57% to 4.30%, and inter-assay CV values between 1.71% and 4.67% for detecting samples at high, medium, and low concentration levels. Concordance with Reagent A showed consistent results in both positive and negative detections.Conclusion:In this study, the anti-HDV IgG reagent (chemiluminescence method) displayed outstanding specificity in detecting clinical samples and exhibited a high conformity rate with commercialized reagents, making it potentially suitable for screening anti-HDV IgG in HBsAg-positive samples.

Objective:This study aims to evaluate the quality and explore the preliminary clinical applications of a domestically developed hepatitis D virus nucleic acid quantification reagent (abbreviated as"domestic HDV RNA reagent").Methods:The sensitivity and accuracy of the reagent were evaluated in accordance with the WHO HDV RNA international standard, employing the Bio-Rad CFX Opus 96 real-time fluorescence quantitative PCR analysis system. Serial dilutions of pseudo-viruses or cell culture-derived virus were used to determine the linear range of the domestic HDV RNA reagent. Specificity was assessed using positive samples of HAV, HBV, HCV infection, and HEV national reference materials. Precision was evaluated with samples at both high and low concentrations. In a comparative analysis, 30 HDV IgG positive samples were tested using both the domestic HDV RNA reagent and the RoboGene HDV RNA kit based on the ABI 7500 FAST DX system. The Pearson correlation coefficient (r) was used to examine the correlation between the two reagents.Results:The domestic HDV RNA reagent demonstrated a high sensitivity of up to 6 IU/ml, consistent with that of the comparator reagent. The calibration curve for WHO HDV RNA standards had a slope of -3.286, with an amplification efficiency of 101.6%. The linear detection range spanned from 10 to 10 8 IU/ml for eight HDV genotypes. The domestic HDV RNA reagent exhibited exceptional specificity, without cross-reactivity observed with HAV, HBV, HCV, or HEV. Accuracy assessments at five concentration levels met the required standards, with intra-assay precision coefficient of variation ( CV) ranging from 1.20% to 4.20%, and inter-assay precision CV from 1.20% to 7.90%. The detection results for HDV IgG positive samples were highly correlated with the comparator reagent ( r=0.984, P<0.001), achieving a diagnostic accuracy of 100% compared to sequencing results. Conclusion:In this study, the domestic HDV RNA reagent possesses excellent specificity, accuracy, precision, and a broad linear range, attaining a sensitivity level on par with international reagents of the same type.

Objective:To discuss the relationship between 18F-FDG PET/CT metabolic parameters and clinical pathological indicators and prognosis in cutaneous malignant melanoma (CMM). Methods:A total of 100 CMM patients (62 males, 38 females, age (56.5±2.5) years) who underwent 18F-FDG PET/CT scans at the Second Xiangya Hospital of Central South University from August 2013 to November 2022 were retrospectively enrolled. Clinical pathological indicators (such as primary site, TNM staging, sentinel lymph node (SLN) status) and metabolic parameters (SUV max, metabolic tumor volume (MTV), total lesion glycolysis (TLG), whole-body MTV (wb-MTV), and whole-body TLG (wb-TLG)) were collected. ROC curve analyses were used to determine the PET parameters thresholds for progression-free survival (PFS) and melanoma-specific survival (MSS). Kaplan-Meier survival analysis, univariate and multivariate Cox proportional hazards regression models were used to analyze the prognosis of patients′ PFS and MSS, and a nomogram survival prediction model was constructed. Results:Results of ROC curve analyses showed that the thresholds of SUV max of primary tumor (p-SUV max), MTV of primary tumor (p-MTV), TLG of primary tumor (p-TLG), wb-MTV and wb-TLG for predicting PFS and MSS were 7.13, 2.24 cm 3, 6.98 g, 2.57 cm 3, 8.04 g and 9.09, 2.34 cm 3, 7.44 g, 2.24 cm 3, 9.17 g, respectively. Results of univariate analysis indicated that several clinical pathological indicators and metabolic parameters were prognostic risk factors for PFS and MSS. Results of multivariate analysis indicated that metastases of SLN (hazard ratio( HR)=2.54, 95% CI: 1.09-5.90; P=0.030) and wb-TLG>8.04 g( HR=2.58, 95% CI: 1.17-5.72; P=0.019) were independent prognostic risk factors for PFS, while metastases of SLN ( HR=4.53, 95% CI: 1.54-13.35; P=0.006) and wb-TLG>9.17 g ( HR=2.48, 95% CI: 1.26-4.89; P=0.009) were independent risk prognostic factors for MSS. A nomogram survival prediction model based on PET metabolic parameter (wb-TLG) and clinical pathological indicator (SLN status) can effectively predict the prognosis of CMM patients. Conclusions:Clinical pathological parameters and PET parameters are associated with the prognosis of CMM patients. SLN status is critical for prognosis.

Objective:To investigate the effect of 18F-FDG combined with 18F-prostate specific membrane antigen (PSMA)-1007 PET/CT on TNM staging and clinical treatment decision of patients with prostate cancer. Methods:Clinical data and PET/CT images of 31 patients (age (69.9±9.2) years) with prostate cancer who underwent PET/CT imaging with 18F-FDG and 18F-PSMA-1007 (dual-tracer imaging) in the Second Xiangya Hospital of Central South University from June 2020 to March 2022 were retrospectively analyzed. Paired χ2 test was used to compare the diagnostic efficacy of 18F-FDG, 18F-PSMA-1007 and combined imaging for diagnosing primary prostate cancer, regional lymph node metastases and distant metastases, and to analyze the influence of combined imaging on clinical treatment decision. Results:There were 282 metastatic sites in 31 patients, including 46 regional lymph node metastases in 13 patients and 236 distant metastases in 15 patients. The detection rates of 18F-PSMA-1007 PET/CT and combined imaging for primary lesions were higher than the detection rate of 18F-FDG PET/CT (100%(31/31), 100%(31/31) vs 64.5%(20/31); χ2=13.37, P<0.001). Based on analysis of patients, the detection rates of 18F-PSMA-1007 PET/CT and combined imaging for regional lymph node metastases were higher than the detection rate of 18F-FDG PET/CT (12/13, 12/13 vs 6/13; χ2=4.51, P=0.034), and the 3 detection rates for distant metastases were also significantly different (15/15, 15/15 vs 10/15; χ2=6.00, P=0.042). Based on analysis of lesions, the detection rates of 18F-PSMA-1007 PET/CT and combined imaging for regional lymph node metastases were higher than the detection rate of 18F-FDG PET/CT (95.7%(44/46), 97.8%(45/46) and 45.7%(21/46); χ2 values: 25.37-49.56, all P<0.001). The detection rate of combined imaging for distant metastases was higher than that of 18F-FDG or 18F-PSMA-1007 PET/CT alone (96.2%(227/236) vs 68.6%(162/236), 58.9%(139/236)); and the detection rate of 18F-FDG PET/CT was higher than that of 18F-PSMA-1007 PET/CT ( χ2 values: 4.85-94.22, all P<0.05). Clinical treatment decisions in 10 patients (32.3%, 10/31) were changed based on the results of combined imaging. Conclusion:For prostate cancer with suspected distant metastases, 18F-FDG and 18F-PSMA-1007 dual-tracer PET/CT imaging can improve staging and guide clinical treatment decisions.