Melatonin suppresses tumor proliferation and metastasis by targeting GATA2 in endometrial cancer.

Endometrial cancer (EC) is a reproductive system disease that occurs in perimenopausal and postmenopausal women. However, its etiology is unclear. Melatonin (MT) has been identified as a therapeutic agent for EC; however, its exact mechanism remains unclear. In the present study, we determined that GATA-binding protein 2 (GATA2) is expressed at low levels in EC and regulated by MT. MT upregulates the expression of GATA2 through MT receptor 1A (MTNR1A), whereas GATA2 can promote the expression of MTNR1A by binding to its promoter region. In addition, in vivo and in vitro experiments showed that MT inhibited the proliferation and metastasis of EC cells by upregulating GATA2 expression. The protein kinase B (AKT) pathway was also affected. In conclusion, these findings suggest that MT and GATA2 play significant roles in EC development.

Mannose-Binding Lectin 2 as a Potential Therapeutic Target for Hepatocellular Carcinoma: Multi-Omics Analysis and Experimental Validation.

Mannose-binding lectin 2 (MBL2), a member of the multimeric lectin family, is crucial in immune regulation and tumor development. MBL2 gene polymorphisms are associated with the risk and prognosis of various tumors, including hepatocellular carcinoma (HCC). Its functional role in HCC remains largely unclear. In this study, we aimed to identify whether MBL2 is a key regulator and a potential therapeutic target for HCC. A bioinformatics analysis revealed close relationships among MBL2 downregulation, the tumor-associated proliferation and metastasis pathway, and tumor immunosuppressive microenvironments. Lower expression of MBL2 in HCC patients was linked to an unfavorable prognosis. A cell counting kit-8 assay, colony formation assay, transwell migration assay, and wound healing assay further confirmed that the overexpression of MBL2 could directly inhibit the proliferation and metastasis of HCC. Moreover, MBL2 expression was regulated by miR-34c-3p, as confirmed by the dual-luciferase reporter assay, thereby demonstrating tumor progression in HCC cells. Thus, our study offers the first comprehensive confirmation of the role of MBL2 in the development of HCC through multi-omics analysis and experimental validation. Furthermore, miR-34c-3p was found to be an upstream mechanism of the downregulation of MBL2 expression and could be a promising therapeutic target, expanding treatment options for patients with HCC.

O-GlcNAc modification mediates aquaporin 3 to coordinate endometrial cell glycolysis and affects embryo implantation.

Introduction: O-linked ß-D-N-acetylglucosamine (O-GlcNAc) modification is a post-translational modification in which a single O-GlcNAc is added to serine or threonine residues in nuclear, cytoplasmic, and mitochondrial proteins, and is involved in a variety of physiological processes. Objectives: In the present study, the role of O-GlcNAcylation in embryo implantation was evaluated. Furthermore, whether O-GlcNAcylation is involved in orchestrating glucose metabolism to influence endometrial cell physiological functions was investigated. Methods: Different endometrial tissues were detected using immunohistochemistry. Pregnant mouse models were established to verify molecular expression. O-GlcNAc transferase and aquaporin 3 (AQP3) knockdown were used to detect embryo implantation efficiency in vitro and in vivo. Western blotting and immunofluorescence were used to detect protein expression and stability. Dual luciferase reporter assay and chromatin immunoprecipitation (ChIP) were used to verify the binding transcription factor. Glycolysis was detected using bioenergy analyzer, and metabolites were analyzed using isotope 13C-labeled LC-MS. Metabolic-related genes were determined using RNA sequencing. Results: Activation of endometrial hexosamine biosynthetic pathway (HBP) caused elevated O-GlcNAcylation during the window of implantation, affecting endometrial cell function and embryo implantation. Specifically, elevated O-GlcNAcylation increased glucose uptake via glucose transporter 1 (GLUT1) leading to glucose metabolic flow into the pentose phosphate pathways and HBP, which regulate the metabolic reprogramming of endometrial cells. Furthermore, O-GlcNAcylation mediated the intracellular transport of glycerol to support and compensate for glycolysis through regulation of AQP3. Unexpectedly, elevated AQP3 also increased glucose uptake via GLUT1. These processes maintained higher metabolic requirements for endometrial physiology. Furthermore, the transcription factor SP1 specifically bound to the AQP3 promoter region, and O-GlcNAcylation of SP1 increased its stability and transcriptional regulation of AQP3 which is associated with O-GlcNAcylation of SP1. Conclusion: Overall, O-GlcNAcylation regulated glucose metabolism in endometrial cells, and AQP3-mediated compensation provides new insights into the communication between glycolysis and O-GlcNAcylation.

NF-κB and EGFR participate in S1PR3-mediated human renal cell carcinomas progression.

The bioactive lipid sphingosine 1-phosphate (S1P) is implicated in many pivotal processes for the physiological and pathological actions via activating five types of G-protein-coupled S1P receptors (S1PR1-5). The role of S1P in renal cell carcinoma (RCC) and its receptor subtype specific mediating mechanism are poorly studied. So we focus on the regulatory role of S1P in RCC progression and the receptor subtypes involved in S1P-induced actions, intending to further clarify a novel therapeutic target for RCC. Analysis of The Cancer Genome Atlas (TCGA) databases showed that the patients with high expression of S1PR3 had significantly worse overall than with low expression. We further demonstrated that S1P could promote proliferation, migration, and epithelial-mesenchymal transition (EMT) of renal cancer cells in vitro, and the actions were enhanced with the increase of S1PR3 expression. Meanwhile, the results in animal experiments also showed that S1PR3 could accelerate tumorigenesis and metastasis of RCC. Our study also clarified the mechanism for S1P induced cell proliferation is mediated by S1PR3/Gi/p38/Akt/p65/cyclin D1-CDK4 pathway and the main pathway for migration is S1PR3/Gi/q/ERK/p38/p65. In addition, S1PR3 was involved in epidermal growth factor (EGF)-induced actions by enhancing protein expression, not by transactivation of epidermal growth factor receptor (EGFR). These results also further supported our conclusion that the carcinogenic role of S1P/S1PR3 axis. Thus, our findings provide that S1PR3 may be a promising small molecular therapeutic target for S1PR3 expressed cancers.

LPA receptor1 antagonists as anticancer agents suppress human lung tumours.

Lysophosphatidic acid (LPA), as a bioactive lipid, plays a variety of physiological and pathological roles via activating six types of G-protein-coupled LPA receptors (LPA1-6). Our preliminary study found that LPA1 is highly expressed in lung cancer tissues compared with paracancerous tissues, but the role of LPA1 in lung carcinoma is unclear. This study aimed to elucidate the association between LPA1 and lung tumour behaviour at the cellular and animal model levels. We found that LPA promoted the migration, proliferation and colony formation of a lung cancer cell line (A549). LPA1 and LPA3 are preferentially expressed in A549 cells, and both Ki16425 (LPA1 and LPA3 antagonist) and ono7300243 (LPA1 antagonist) completely blocked the LPA-induced actions. These results were further verified by experiments of the LPA1/3 overexpression and LPA1 knockdown A549 cells. Furthermore, LPA1 overexpression and knockdown A549 cells were used to assess the in vivo tumour-bearing animal model and the mechanism underlying LPA-induced actions. In the animal model, A549 cell-derived tumour volume was significantly increased by LPA1 overexpression and significantly decreased by LPA1 knockdown respectively, suggesting that LPA1 is a regulator of in vivo tumour formation. Our results also indicated that the LPA1/Gi/MAP kinase/NF-κB pathway is involved in LPA-induced oncogenic actions in A549 cells. Thus, targeting LPA1 may be a novel strategy for treating lung carcinoma.

Octahedral-shaped perovskite nanocrystals and their visible-light photocatalytic activity.

Octahedral-shaped perovskite PbTiO3 nanocrystals (PT OCT) with well-defined {111} facets exposed have been successfully synthesized via a facile hydrothermal method by using LiNO3 as an ion surfactant. The Li-O bond on the surface of PT OCT nanocrystals is essential to the stability of such nanocrystals and also results in a dramatic high visible-light photocatalytic activity.