Activated Alpha-2 Macroglobulin Improves Insulin Response via LRP1 in Lipid-Loaded HL-1 Cardiomyocytes

RAB10 promotes breast cancer proliferation migration and invasion predicting a poor prognosis for breast cancer

RAB10, a member of the small GTPase family, has complex biological functions, but its role in breast cancer (BC) remains unclear. The aim of this study was to investigate the relationship between RAB10's role in BC, its biological functions, and BC prognosis. An online database was used to analyze the correlation between differential expression of RAB10 in BC and prognosis. The results of immunohistochemical assays in clinical cohorts were combined with the database analysis. The chi-square test and COX regression were employed to analyze the correlation between RAB10 and pathological features of BC. MTT, Transwell, and wound healing assays were conducted to detect BC cell proliferation, invasion, and metastatic ability. Bioinformatics techniques were employed to explore the correlation between RAB10 and BC tumor immune cell infiltration, and to speculate the biological function of RAB10 in BC and related signaling pathways. Our findings suggest that RAB10 expression is elevated in BC and is associated with HER2 status, indicating a poor prognosis for BC patients. RAB10 can promote the proliferation, migration, and invasion ability of BC cells in vitro. RAB10 is also associated with BC immune cell infiltration and interacts with multiple signaling pathways. RAB10 is a potential biomarker or molecular target for BC.

2-Hydroxypropyl-β-cyclodextrin Regulates the Epithelial to Mesenchymal Transition in Breast Cancer Cells by Modulating Cholesterol Homeostasis and Endoplasmic Reticulum Stress

Cholesterol metabolism affects endoplasmic reticulum (ER) stress and modulates epithelial-mesenchymal transition (EMT). Our previous study demonstrated that 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) attenuated EMT by blocking the transforming growth factor (TGF)-β/Smad signaling pathway and activating ER stress in MDA-MB-231 cells. To further assess the detailed mechanisms between cholesterol metabolism, ER stress, and EMT, LXR-623 (an agonist of LXRα) and simvastatin were used to increase and decrease cholesterol efflux and synthesis, respectively. Here, we found that high HP-β-CD concentrations could locally increase cholesterol levels in the ER by decreasing LXRα expression and increasing Hydroxymethylglutaryl-Coenzyme A reductase (HMGCR) expression in MDA-MB-231 and BT-549 cells, which triggered ER stress and inhibited EMT. Meanwhile, tunicamycin-induced ER stress blocked the TGF-β/Smad signaling pathway. However, low HP-β-CD concentrations can decrease the level of membrane cholesterol, enhance the TGF-β receptor I levels in lipid rafts, which helped to activate TGF-β/Smad signaling pathway, inhibit ER stress and elevate EMT. Based on our findings, the use of high HP-β-CD concentration can lead to cholesterol accumulation in the ER, thereby inducing ER stress, which directly suppresses TGF-β pathway-induced EMT. However, HP-β-CD is proposed to deplete membrane cholesterol at low concentrations and concurrently inhibit ER stress and induce EMT by promoting the TGF-β signaling pathways.