ITCH facilitates proteasomal degradation of TXNIP in hypoxia- induced lung cancer cells.

BACKGROUND: Lung cancer (LC) is one of the most common cancers and a leading cause of cancer-related deaths worldwide. In many pathological conditions, particularly in the tumor microenvironment, cells and tissues frequently exist in a hypoxic state. Here, we evaluated Itchy E3 ubiquitin protein ligase (ITCH) expression in LC cells following hypoxia treatment. METHODS: LC cell lines were treated with hypoxic condition. Cell migration, invasion, inflammation, reactive oxygen species (ROS) production, and apoptosis of LC cells were determined by wound healing assay, Transwell invasive assay, ELISA, DCFH-DA staining, and flow cytometry, respectively. qPCR and WB were used to determine the expression of ITCH and TXNIP. Co-IP was performed to assess the interaction between ITCH and TXNIP. RESULTS: ITCH expression was downregulated in LC cells under hypoxic conditions. Next, LC cells were subjected to hypoxic conditions and changes in cell viability and metastasis were determined. Hypoxic conditions resulted in increased migration and invasion abilities of LC cells. Intracellular reactive oxygen species (ROS) production, inflammation, and apoptosis were also promoted by hypoxia. We found that ITCH overexpression led to the proteasomal degradation of thioredoxin-interacting protein (TXNIP), whereas the expression of the ITCH C830A mutant did not affect TXNIP levels in LC cells. The gain-of-function experiment demonstrated that migration, invasion, ROS generation, inflammation, and apoptosis of hypoxia-conditioned LC cells were ameliorated by ITCH overexpression, whereas the ITCH C830A mutant did not cause any changes in these phenotypes. Furthermore, the contribution of TXNIP knockdown and ITCH overexpression to the hypoxia-induced features in LC cells with ITCH C830A was found to be similar. CONCLUSION: Our results suggest a novel mechanism underlying the changes in ITCH-mediated malignant phenotypes of hypoxia-conditioned LC cells via TXNIP.

Baicalein Attenuates Brain Iron Accumulation through Protecting Aconitase 1 from Oxidative Stress in Rotenone-Induced Parkinson's Disease in Rats.

Aconitase 1 (ACO1) links oxidative stress and iron accumulation in Parkinson's disease (PD). ACO1 loses its aconitase activity and turns into iron regulatory protein 1 (IRP1) upon oxidative stress. IRP1 plays an important role in the accumulation of intracellular iron. Baicalein is a flavonoid isolated from the roots of Scutellaria baicalensis. The present results show that baicalein could bind to ACO1 and protect its isoform from the oxidative stress induced by reactive oxygen species (ROS) and reactive nitrogen species (RNS). Furthermore, baicalein promoted aconitase activity and inhibited IRP1 activation in rotenone-induced PD models. Additionally, baicalein decreased the hydroxyl radicals generated by iron. In conclusion, baicalein attenuated iron accumulation and iron-induced oxidative stress in the brain of PD rats by protecting ACO1.

Upregulation of lncRNA NIFK-AS1 in hepatocellular carcinoma by m6A methylation promotes disease progression and sorafenib resistance.

Long non-coding RNAs (LncRNAs) have recently emerged as vital regulators in the development and progression of hepatocellular carcinoma (HCC), providing new opportunities as novel therapeutic targets. Here we identified the lncRNA NIFK-AS1 as being highly expressed in HCC tissues and cells and showed this up-regulation resulted from METTL3-dependent m6A methylation. Functionally, knockdown of NIFK-AS1 inhibited the proliferation, colony formation, migration, and invasion of HCC cells. Moreover, these effects were elicited though AKT1 and we uncovered a ceRNA network involving an NIFK-AS1/miR-637/AKT1 axis with downstream effects on HCC progression involving regulation of MMP-7 and MMP-9 expression. From the clinical perspective, we showed that knockdown of NIFK-AS1 sensitized HCC cells to sorafenib through the up-regulation of the drug transporters OATP1B1 and OATP1B3. Clinical investigations showed HCC patients with low NIFK-AS1 expression benefited from sorafenib therapy and this phenomenon was reproduced in patient-derived tumor xenograft models (PDX) comparing HCC with low and high expression of NIFK-AS1. Taken together, these results suggest an essential role for NIFK-AS1 in HCC progression and promote NIFK-AS1 as a new therapeutic target and predictor of sorafenib benefit in HCC patients.

Pinocembrin Ameliorates Cognitive Impairment Induced by Vascular Dementia: Contribution of Reelin-dab1 Signaling Pathway.

BACKGROUND: As a substrate of apoER2, Reelin has been verified to exert neuroprotection by preventing memory impairment. Pinocembrin is the most abundant natural flavonoid found in propolis, and it has been used to exert neuroprotection, blood-brain barrier protection, anti-oxidation, and inflammation diminishing, both in vitro and in vivo. However, the roles and molecular mechanisms of pinocembrin in neurobehavioral outcomes and neuronal repair after vascular dementia are still under investigation. PURPOSE: To explore the role of pinocembrin in the involvement of the Reelin-dab1 signaling pathway in improving memory impairment, both in cell culture and animals experiments. MATERIAL AND METHODS: Behavioral tests were conducted on day 48 to confirm the protection of pinocembrin against cognitive impairment. Cell and molecular biology experiments demonstrated that the Reelin-dab1 pathway mediates the underlying mechanism of cognitive improvement by pinocembrin. RESULTS: It was showed that pinocembrin alleviated learning and memory deficits induced by vascular dementia, by inducing the expression of Reelin, apoER2, and p-dab1 in the hippocampus. The expression of Reelin and p-dab1 was both inhibited following Reelin RNA interference in SH-SY5Y prior to oxygen glucose deprivation (OGD) injury, suggesting that Reelin played a core role in pinocembrin's effect on OGD in vitro. CONCLUSION: Pinocembrin improves the cognition via the Reelin-dab1 signaling pathway.