Clinical and Functional Significance of Intracellular and Extracellular microRNA-25-3p in Osteosarcoma

Although there is considerable evidence indicating that the dysregulation of microRNAs (miRNAs) in malignant tumors plays a role in tumor development, the overall function of miRNAs and their clinicopathological significance are not well understood. In this retrospective analysis of 45 biopsy specimens from osteosarcoma (OS) patients, we investigated the functional and clinical significance of miR-25-3p in OS, which we previously identified as a highly expressed miRNA in OS patients' serum. We observed that miR-25-3p dysregulation in human OS tissues was negatively correlated with the clinical prognosis, whereas the expression level of its target gene, Dickkopf WNT Signaling Pathway Inhibitor 3 (DKK3), was positively correlated with the clinical prognosis. Endogenous miR-25-3p upregulation promoted tumor growth, invasion, and drug resistance, which was consistent with DKK3 silencing in OS cells. In addition, secretory miR-25-3p was embedded in tumor-derived exosomes, where it promoted capillary formation and the invasion of vascular endothelial cells. Overall, our results show that miR-25-3p has intracellular and extracellular oncogenic functions as well as clinicopathological relevance in OS, indicating its potential as a novel diagnostic and therapeutic tool for the clinical management of this disease.

New Left Lobe Transplantation Procedure with Caval Reconstruction Using an Inverted Composite Graft for Chronic Budd-Chiari Syndrome in Living-Donor Liver Transplantation-A Case Report

When the Budd-Chiari syndrome (BCS) lesion extends to the inferior vena cava (IVC) or the orifices of the hepatic vein, the thickened IVC and/or hepatic vein wall must be removed and IVC reconstruction is required in living-donor liver transplantation (LDLT). In various reports about IVC resection in LDLT for BCS, there are none about left lobe liver transplantation with reconstruction of the retrohepatic IVC (rhIVC). To overcome removal and reconstruction of the rhIVC in LDLT for BCS, we introduced a composite IVC graft that is applicable to both right and left lobe partial liver grafts for LDLT for BCS. Pathogenic IVC was removed together with the native liver between the lower edge of the right atrium and 5 cm above the renal vein junction with the use of venovenous bypass. The e-polytetrafluoroethylene graft was anastomosed to the suprarenal intact IVC. Then the native part was detached at the level of just above the renal junction. The composite graft was inverted and a half rim of the native part of the graft was anastomosed to the posterior wall of the right atrium. Next, the common venous orifice of the left lobe graft was anastomosed to the wall defect which was composed of the anterior wall of the right atrium and the distal end of the native part of the composite graft. In conclusion, our inverted composite graft technique will overcome the weak points of LDLT for BCS, such as incomplete removal of the pathogenic caval wall and reconstruction of the rhIVC.

Clinical significance of circulating miR-25-3p as a novel diagnostic and prognostic biomarker in osteosarcoma

Background

Emerging evidence has suggested that circulating microRNAs (miRNAs) in body fluids have novel diagnostic and prognostic significance for patients with malignant diseases. The lack of useful biomarkers is a crucial problem of bone and soft tissue sarcomas; therefore, we investigated the circulating miRNA signature and its clinical relevance in osteosarcoma.

Methods

Global miRNA profiling was performed using patient serum collected from a discovery cohort of osteosarcoma patients and controls and cell culture media. The secretion of the detected miRNAs from osteosarcoma cells and clinical relevance of serum miRNA levels were evaluated using in vitro and in vivo models and a validation patient cohort.

Results

Discovery screening identified 236 serum miRNAs that were highly expressed in osteosarcoma patients compared with controls, and eight among these were also identified in the cell culture media. Upregulated expression levels of miR-17-5p and miR-25-3p were identified in osteosarcoma cells, and these were abundantly secreted into the culture media in tumor-derived exosomes. Serum miR-25-3p levels were significantly higher in osteosarcoma patients than in control individuals in the validation cohort, with favorable sensitivity and specificity compared with serum alkaline phosphatase. Furthermore, serum miR-25-3p levels at diagnosis were correlated with patient prognosis and reflected tumor burden in both in vivo models and patients; these associations were more sensitive than those of serum alkaline phosphatase.

Conclusions

Serum-based circulating miR-25-3p may serve as a non-invasive blood-based biomarker for tumor monitoring and prognostic prediction in osteosarcoma patients.

Measurement of thickness of film deposited on the plasma-facing wall in the QUEST tokamak by colorimetry

After several experimental campaigns in the Kyushu University Experiment with Steady-state Spherical Tokamak (QUEST), the originally stainless steel plasma-facing wall (PFW) becomes completely covered with a deposited film composed of mixture materials, such as iron, chromium, carbon, and tungsten. In this work, an innovative colorimetry-based method was developed to measure the thickness of the deposited film on the actual QUEST wall. Because the optical constants of the deposited film on the PFW were position-dependent and the extinction coefficient k₁ was about 1.0-2.0, which made the probing light not penetrate through some thick deposited films, the colorimetry method developed can only provide a rough value range of thickness of the metal-containing film deposited on the actual PFW in QUEST. However, the use of colorimetry is of great benefit to large-area inspections and to radioactive materials in future fusion devices that will be strictly prohibited from being taken out of the limited area.