Role of RIPK3 in lipid metabolism and postnatal overfeeding-induced metabolic disorders in mice.

Postnatal overfeeding can increase the long-term risk of metabolic disorders, such as obesity, but the underlying mechanisms remain unclear and treatment approaches are limited. Receptor-interacting protein kinase 3 (RIPK3) is associated with several metabolic diseases. We investigated the effects of RIPK3 on neonatal overfeeding-related metabolic disorders. On postnatal day 3, litter sizes were adjusted to 9-10 (normal litters, NL) or 2-3 (small litters, SL) mice per dam to mimic postnatal overfeeding. After weaning, NL and SL mouse were fed normal diet. We generated an adeno-associated virus (AAV) carrying short hairpin RNA (shRNA) against Ripk3 and an empty vector as a control. The NL and SL groups were treated intravenously with 1×1012 vector genome of AAV vectors at week 6. The SL group showed a higher body weight than the NL group from week 3 of age through adulthood. At weeks 6 and 13, the SL group exhibited impaired glucose and insulin tolerance, RIPK3 up-regulation, and lipid accumulation in liver and adipose tissues. In the SL group, the genes involved in lipid synthesis and lipolysis were increased, whereas fatty acid ß-oxidation-related genes were weakened in adipose tissue and liver. At week 13, AAV-shRNA-Ripk3 ameliorated adipose tissue hypertrophy, hepatic steatosis, insulin resistance, and dysregulated lipid metabolism in the adipose tissue and liver of SL mice. These findings support a novel mechanism underlying the pathogenesis of postnatal overfeeding-related metabolic disorders and suggest potential therapeutic targets.

Mutations in COMP cause familial carpal tunnel syndrome.

Carpal tunnel syndrome (CTS) is the most common peripheral nerve entrapment syndrome, affecting a large proportion of the general population. Genetic susceptibility has been implicated in CTS, but the causative genes remain elusive. Here, we report the identification of two mutations in cartilage oligomeric matrix protein (COMP) that segregate with CTS in two large families with or without multiple epiphyseal dysplasia (MED). Both mutations impair the secretion of COMP by tenocytes, but the mutation associated with MED also perturbs its secretion in chondrocytes. Further functional characterization of the CTS-specific mutation reveals similar histological and molecular changes of tendons/ligaments in patients' biopsies and the mouse models. The mutant COMP fails to oligomerize properly and is trapped in the ER, resulting in ER stress-induced unfolded protein response and cell death, leading to inflammation, progressive fibrosis and cell composition change in tendons/ligaments. The extracellular matrix (ECM) organization is also altered. Our studies uncover a previously unrecognized mechanism in CTS pathogenesis.

RETRACTED: Astragalus polysaccharide promotes proliferation and osteogenic differentiation of bone mesenchymal stem cells by down-regulation of microRNA-152.

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editor-in-Chief and the authors. Given the comments regarding Figure 1B of this article https://pubpeer.com/publications/C7C586297DA52213799146DCD21CD4, the journal requested the corresponding authors to provide the raw data of the results presented by the article. While initially fulfilling the request, the authors eventually requested the retraction of the article as they were not able to confirm the accuracy of the data and the conclusions of the article.

Long Non-Coding RNA Urothelial Carcinoma Associated 1 Promotes Proliferation, Migration and Invasion of Osteosarcoma Cells by Regulating microRNA-182.

BACKGROUND/AIMS: Previous studies demonstrated the oncogenic roles of lncRNA UCA1 in osteosarcoma. This study aimed to explore the internal molecular mechanism of UCA1 on promoting osteosarcoma cell proliferation, migration and invasion. METHODS: qRT-PCR was conducted to measure the expression levels of UCA1, miR-182 and TIMP2. Cell transfection was used to change the expression levels of UCA1, miR-182 and TIMP2. Cell viability, migration, invasion and apoptosis were measured using CCK-8 assay, two-chamber migration (invasion) assay and Guava Nexin assay, respectively. The associations between UCA1, miR-182 and iASPP were analyzed by dual luciferase activity assay. The protein expression levels of key factors involved in cell apoptosis, PI3K/AKT/GSK3ß pathway and NF-κB pathway, as well as p53, Rb, RECQ family and iASPP were evaluated by western blotting. RESULTS: UCA1 was highly expressed in osteosarcoma MG63 and OS-732 cells. Knockdown of UCA1 inhibited OS-732 cell viability, migration and invasion, but promoted cell apoptosis. miR-182 was up-regulated in OS-732 cells after UCA1 knockdown and participated in the effects of UCA1 on OS-732 cells. TIMP2 was downstream factor of miR-182 and involved in the regulatory roles of miR-182 on OS-732 cell viability, migration, invasion, apoptosis, as well as PI3K/AKT/GSK3ß and NF-κB pathways. UCA1 knockdown up-regulated p53, Rb and RECQL5 levels in OS-732 cells, while down-regulated the expression of iASPP. TGF-ß or TNF-α treatment could enhance the expression of UCA1 in OS-732 cells. CONCLUSION: Our research verified that UCA1 exerted oncogenic roles in osteosarcoma cells by regulating miR-182 and TIMP2, as well as PI3K/AKT/GSK3ß and NF-κB pathways.

Knockdown MiR-302b Alleviates LPS-Induced Injury by Targeting Smad3 in C28/I2 Chondrocytic Cells.

BACKGROUND/AIMS: Osteoarthritis (OA) is one of the most common chronic degenerative diseases. Many studies have demonstrated the role of microRNAs (miRNAs) in OA; however, the role of miR-302b in OA remains elusive. The aim of this study was to identify the role of miR-302b in LPS-induced injury in chondrocytes. METHODS: Human OA chondrocytes (C28/12 cell line) were transfected with miR-302b inhibitor and miR-302b mimic to investigate the effects of miR-302b expression on chondrocyte apoptosis and inflammation, and to identify the miR-302b target proteins. RESULTS: LPS treatment of chondrocytes significantly reduced cell viability and increased apoptotic rate. LPS treatment also increased the expression of inflammatory cytokines compared to control. miR-302b was up-regulated in LPS-induced chondrocytes. miR-302b was either suppressed or overexpressed in LPS-induced chondrocytes by transient transfection. miR-302b mimic transfection accelerated the effects of LPS on cell viability, apoptosis and inflammation. Of contrast, miR-302b inhibition represented a reverse effect. Dual luciferase activity demonstrated that Smad3 is a direct target for miR-302b and its expression was negatively regulated by miR-302b. In addition, miR-302b inhibition suppressed inflammation in LPS treated chondrocytes by up-regulating Smad3 expression. Moreover, LPS induced down-regulation of Notch and mTOR signaling pathway-related protein expressions, and miR-302b inhibition increased the expressions of Notch and mTOR signaling pathway-related proteins. We further found that miR-302b negatively regulated Notch2 levels through direct targeting its 3'UTR. CONCLUSIONS: These results suggest that miR-302b suppression may function as a protector in suppressing the inflammation during the development and progression of OA by up-regulating the target Smad3 expression.

Meta-analysis of concurrent chemoradiotherapy in the treatment of locoregionally advanced nasopharyngeal carcinoma.

BACKGROUND: With radiotherapy (RT) alone, the five-year overall survival (OS) rate for advanced nasopharyngeal carcinoma (NPC) can only reach 40%, the ratio of distant metastasis (DM) is 36-40%. This meta-analysis was performed to compare the clinical efficacy of concurrent chemoradiotherapy (CCRT) with RT alone in the treatment of locoregionally advanced NPC. METHODS: The related literature were retrieved and reviewed by two independent investigators from the followed electronic databases: Review manager 5.3 software (Cochrane Collaboration, London, United Kingdom) was applied for statistical analysis. RESULTS: A total of 16 trials with 2576 patients were recruited according to the criterion. The odds ratios of 3 and 5 years OS was 0.53 (95% confidence interval [95% CI]: 0.44-0.64) and 0.58 (95% CI: 0.48-0.71), which confirmed the significant improvement of CCRT compared with RT alone (P < 0.001). CCRT also reduced the risk of locoregional control failure and DM in locoregionally advanced NPC patients. CONCLUSIONS: The results suggested that CCRT was more beneficial when compared with RT alone in locoregionally advanced NPC patients. Further study is needed to perform to confirm this effect.

TIMP-3 gene transfection suppresses invasive and metastatic capacity of human hepatocarcinoma cell line HCC-7721.

BACKGROUND: Tissue inhibitor of metalloproteinases (TIMPs) can restrain the tumor growth by their protein property and matrix metalloproteinases (MMPs) inhibition. There are currently four known TIMP family members-TIMP-1, 2, 3, 4. We determined whether increasing levels of TIMP-3 expression could suppress the malignant phenotype of human hepatocarcinoma cell line HCC-7721. METHODS: A recombinant expression vector, which contained full-length cDNA of human TIMP-3, was constructed and transfected into the human hepatocarcinoma cell line HCC-7721 by the lipofectamine technique. In vitro and in vivo tests such as Western blotting, immunohistochemistry as well as xenografting in nude mice were used to analyze expression levels of TIMP and MMP, and changes in malignant phenotype after the gene transfection. RESULTS: TIMP-3 expression in TIMP-3 gene-transfected HCC-7721 cells was upregulated as assessed by Western blotting. The ability of in vitro invasion through a Boyden chamber was significantly decreased compared to controls. Following subcutaneous injection into nude mice, the TIMP-3 transfected cells suppressed primary tumor growth, as characterized by reduced tumor weight, size and microvasculature as well as maintaining the extracellular matrix. CONCLUSION: The results suggest that upregulation of TIMP-3 expression in HCC-7721 cells inhibits invasion capacity in vitro as well as tumorigenic and metastatic potential in nude mice.