Leucine-rich repeat kinase 2 is protective during acute kidney injury through its activation of autophagy in podocytes.

Leucine-rich repeat kinase 2 (LRRK2) is a known regulator of autophagy in a range of cell types. Here, we investigated the role of LRRK2-associated autophagy during acute kidney injury (AKI) and its underlying mechanism(s) of action. Male mice aged 8-weeks were treated with the LRRK2 inhibitor MLi-2 and exposed to lipopolysaccharide (LPS) through intraperitoneal injection or ischemia-reperfusion (IR) surgery. Mice were sacrificed 12 or 24 h post-LPS injection or IR operation and blood was collected for serum creatinine measurements. Kidney cortical tissues were collected for western blot analysis of podocyte-specific markers and autophagy-associated proteins. Renal histopathology was observed through hematoxylin-eosin staining. For cell-based assays, immortalized mouse podocytes were silenced for LRRK2 through siRNA transfection and exposed to LPS or cobalt chloride. Changes in cell viability were investigated using cell counting kit-8, flow cytometry and MTT assays. Expression of podocyte-specific markers and autophagy-associated proteins were analyzed by western blotting. We observed an increase in LRRK2 expression at 12 h post-LPS injection and IR surgery that was accompanied by enhanced autophagy. At 24 h post-treatment, both LRRK2 expression and autophagy declined. Kidney injury was most pronounced in mice treated with MLi-2. Podocytes silenced for LRRK2 showed a loss of cell viability, decreased levels of podocyte-specific protein expression and a suppression of autophagy. Together, these data reveal the protective effects of LRRK2 during AKI through enhanced podocyte autophagy and cell viability.

A Multicenter Randomized Controlled Study of Contrast-enhanced US versus US-guided Biopsy of Focal Liver Lesions.

Background Retrospective or single-center prospective studies with relatively small samples have shown that contrast-enhanced US (CEUS) can improve the diagnostic accuracy of percutaneous biopsy, but larger prospective studies are lacking. Purpose To assess the diagnostic performance of CEUS-guided biopsy (CEUS-GB) of focal liver lesions (FLLs) compared with US-guided biopsy (US-GB) in a prospective multicenter study. Materials and Methods In this randomized controlled study conducted in nine hospitals in China between March 2016 and August 2019, adult participants with FLLs detected with US, CT, or MRI and planned for percutaneous biopsy were randomly assigned to undergo either US-GB or CEUS-GB. Lesions diagnosed as malignant at histopathologic analysis were considered true-positive findings. Benign or indeterminate lesions required further confirmation with either repeat biopsy or clinical follow-up at 6 months or later. The primary endpoint was the diagnostic accuracy rate, and comparison between groups was made using the χ2 test. Results In this study, 2056 participants (1297 men, 759 women; mean age, 58 years ± 11 [SD]) were analyzed: 1030 underwent biopsy with US guidance and 1026 underwent biopsy with CEUS guidance. The overall diagnostic accuracy rate of CEUS-GB was 96% (983 of 1026) versus 93% (953 of 1030) for US-GB (P = .002), CEUS-GB enabled correct identification in 96% of participants (983 of 1026) compared with 92% (953 of 1030) with US-GB (P = .002). The negative predictive value (NPV) for both biopsy methods was moderate but significantly higher for CEUS-GB than for US-GB (74% vs 57%, P = .001). The difference was remarkable for lesions smaller than 2.0 cm, with CEUS-GB showing higher diagnostic accuracy (96% vs 88%, P = .004) and sensitivity (95% vs 87%, P = .007) than US-GB. Among lesions smaller than 2.0 cm, the accuracy of CEUS-GB and US-GB for detection of hepatocellular carcinoma was 93% and 80%, respectively (P = .008), while it was comparable for liver metastases (98% vs 95%, P = .63). Conclusion Contrast-enhanced US-guided biopsy of focal liver lesions is an effective and safe procedure with a higher diagnostic accuracy than US-guided biopsy, especially for lesions smaller than 2.0 cm and for hepatocellular carcinoma diagnosis. Clinical trial registration no. NCT02413437 © RSNA, 2022 Online supplemental material is available for this article.

Paclitaxel-loaded nanobubble targeted to pro-gastrin-releasing peptide inhibits the growth of small cell lung cancer.

OBJECTIVE: The aim of this work was to study the effects of paclitaxel-loaded nanobubbles targeting pro-gastrin-releasing peptide, designated as paclitaxel targeting nanobubbles, on small cell lung cancer (SCLC). METHODS: Paclitaxel targeting nanobubbles were prepared by Thin-film hydration method. Subsequently, the prepared nanomaterials were tested for their in vitro effects on SCLC H446 cells proliferation, apoptosis and motility using the CCK-8 assay, flow cytometry and cell scratch test. Next, the potential molecular regulatory mechanisms of the prepared nanomaterials on H446 cells were evaluated by RT-PCR, Western blot and immunohistochemical detection. Finally, the in vivo effects of the constructed nanomaterials were assessed on SCLC tumor using tumor-burdened nude mice models. RESULTS: Paclitaxel targeting nanobubbles significantly inhibited SCLC cell proliferation and migration, and promoted cell apoptosis. Moreover, the expression levels of Bcl-2, survivin, CDK2 and MMP-2 significantly decreased in SCLC cells treated with paclitaxel targeting nanobubbles, whereas the expression of caspase-3 and Rb were increased. There was a notable decrease in tumor size in vivo in SCLC nude mice models treated with paclitaxel targeting nanobubbles. CONCLUSION: Paclitaxel targeting nanobubbles effectively inhibited the proliferation, migration and invasion of SCLC cells and induced SCLC cells apoptosis. Hence, these nanobubbles show potential in SCLC-targeted drug treatment application.

Nanobubbles as ultrasound contrast agent for facilitating small cell lung cancer imaging.

BACKGROUND: This study is to investigate whether liposome-loaded nanobubbles (NBs) have the potentials to carry anti-pro-gastrin releasing peptide (proGRP) antibody and enhance ultrasound imaging of small cell lung cancer (SCLC). METHODS: NBs were loaded with an antibody against SCLC (H446 cell line). A nude mouse model of SCLC tumor was established by a subcutaneous injection of tumor cell suspension in the dorsal skin. Images for contrast-enhanced ultrasound (CEUS) of xenograft tumors in the model were obtained through an intravenous injection of blank and targeting NBs. RESULTS: The targeted NBs showed a high binding affinity (90.2 ± 3.24%) of the H446 cells in vitro as compared to the blank NBs that have no affinity of the cells. In process of tumor imaging, no mice died of the NB application. CEUS imaging of the targeted NBs manifested significant increases in half-peak time, area under the curve and peak intensity as compared to the blank NBs. In the model of SCLC, treatment with targeting NBs resulted in a large amount of fluorescent dye accumulated in the tumor tissue but not the liver tissue. CONCLUSION: Our results indicate that NBs can carry antibody traveling to the SCLC cells, whereas application of NBs is safe and reliable in serving as ultrasound contrast agents for improving SCLC imaging.

Application of contrast-enhanced ultrasound before inferior vena cava filter recovery.

BACKGROUND: This study aims to investigate the clinical value of contrast-enhanced ultrasound (CEU) before temporary inferior vena cava filter (IVCF) recovery in patients with deep venous thrombosis, in order to provide ultrasound signs for the recovery of IVCF in clinical practice. METHODS: The CEU manifestations of patients with deep vein thrombosis before temporary IVCF recovery were retrospectively analyzed. With the manifestations of digital subtraction angiography (DSA) or results of the surgical recovery of IVCF as the standard, the detection rate of a thrombus in IVCF was compared between conventional ultrasound and CEU, and the role of CEU in detecting complications of IVCF was analyzed. RESULTS: In the 103 patients with IVCF, conventional ultrasound and CEU did not reveal any filter displacement and deformation, as well as infection. In 86 patients, filters were successfully recovered under DSA. In one patient, the filter was removed surgically. In 16 patients, recovery failed or was given up, and inferior vena cava (IVC) angiography was performed. The recovery rate of IVCF was 84.5%. Among all cases, thrombi were found within the filters or around the filter in 23 patients. The detection rate of thrombi was 47.8% (11/23) by conventional ultrasound and 82.6% (19/23) by CEU, and the difference between these two methods was statistically significant (P<0.05). CEU drew a misdiagnosis of thrombus within the filter in one patient, and the diagnosis was not confirmed after the recovery of the filter. The diagnostic coincidence rate of CEU for thrombus in the IVCF was 95.1%, and the positive predictive value was 95%. In another case, the foot of the IVCF pierced out of the wall of the IVC into the intestinal wall; and this was confirmed by DSA. Hence, recovery was given up. CONCLUSIONS: Thrombosis is the main complication after IVCF placement. CEU revealed typical manifestations of thrombi in the IVC, and has overcome the shortcoming of color Doppler ultrasound such as angular dependence. Its detection rate of thrombi within the IVCF was higher compared with conventional ultrasound. Hence, this method can serve as a simple and accurate method for evaluating whether IVCF is suitable for recovery. This study provides a reliable imaging basis for the clinical selection of the means and time of IVCF recovery, reducing unnecessary intervention procedure.