1, 6-O, O-Diacetylbritannilactone from Inula britannica Induces Anti-Tumor Effect on Oral Squamous Cell Carcinoma via miR-1247-3p/LXRα/ABCA1 Signaling

Tumor-derived exosomal miR-1247-3p promotes angiogenesis in bladder cancer by targeting FOXO1

Tumor-derived exosomes are highly correlated with tumor progression and angiogenesis. This study was designed to probe the role of tumor-derived exosomal miR-1247-3p in mediating the angiogenesis in bladder cancer. Exosomes isolation from the culture medium of normal or bladder cancer cell lines was performed using a differential centrifugation method. miR-1247-3p expression in exosomes and cells was detected by quantitative real-time PCR (qRT-PCR). The effect of exosomes on the angiogenesis of human umbilical vein endothelial cells (HUVECs) was assessed using cell counting kit-8 (CCK-8), transwell and tube formation assays. The interaction between miR-1247-3p and forkhead box protein O1 (FOXO1) was studied using luciferase reporter and RNA pull down assays. Exosomes were successfully isolated from T24, UM-UC-3, and SV-HUC-1 cells, as confirmed by corresponding identifications. Functional experiments revealed that exosomes derived from T24 and UM-UC-3 cells significantly enhanced the abilities of proliferation, migration, angiogenesis, and vascular endothelial-derived growth factor (VEGF) secretion in HUVECs. miR-1247-3p was highly expressed in exosomes derived from T24 and UM-UC-3 cells, and exosomes derived from miR-1247-3p inhibitor-transfected cells reduced HUVEC viability, migration, tube formation, and VEGF level. FOXO1 was confirmed as a direct target of miR-1247-3p. Rescue assays suggested that the effect of miR-1247-3p inhibition on the viability, migration, and angiogenesis of HUVECs was partly abrogated by the knockdown of FOXO1. Our data suggest that miR-1247-3p is up-regulated in tumor-derived exosomes, thereby inhibiting FOXO1 expression and facilitating angiogenesis in bladder cancer.

Emerging Insights into Liver X Receptor α in the Tumorigenesis and Therapeutics of Human Cancers

Liver X receptor α (LXRα), a member of the nuclear receptor superfamily, is identified as a protein activated by ligands that interacts with the promoters of specific genes. It regulates cholesterol, bile acid, and lipid metabolism in normal physiological processes, and it participates in the development of some related diseases. However, many studies have demonstrated that LXRα is also involved in regulating numerous human malignancies. Aberrant LXRα expression is emerging as a fundamental and pivotal factor in cancer cell proliferation, invasion, apoptosis, and metastasis. Herein, we outline the expression levels of LXRα between tumor tissues and normal tissues via the Oncomine and Tumor Immune Estimation Resource (TIMER) 2.0 databases; summarize emerging insights into the roles of LXRα in the development, progression, and treatment of different human cancers and their diversified mechanisms; and highlight that LXRα can be a biomarker and therapeutic target in diverse cancers.