miR-138-5p Inhibits Vascular Mimicry by Targeting the HIF-1α/VEGFA Pathway in Hepatocellular Carcinoma

Regulation of the HIF switch in human endothelial and cancer cells

Hypoxia-inducible factors (HIFs) are transcription factors that reprogram the transcriptome for cells to survive hypoxic insults and oxidative stress. They are important during embryonic development and reprogram the cells to utilize glycolysis when the oxygen levels are extremely low. This metabolic change facilitates normal cell survival as well as cancer cell survival. The key feature in survival is the transition between acute hypoxia and chronic hypoxia, and this is regulated by the transition between HIF-1 expression and HIF-2/HIF-3 expression. This transition is observed in many human cancers and endothelial cells and referred to as the HIF Switch. Here we discuss the mechanisms involved in the HIF Switch in human endothelial and cancer cells which include mRNA and protein levels of the alpha chains of the HIFs. A major continuing effort in this field is directed towards determining the differences between normal and tumor cell utilization of this important pathway, and how this could lead to potential therapeutic approaches.

JAM3 promotes cervical cancer metastasis by activating the HIF-1α/VEGFA pathway

Cervical cancer is the fourth most common cancer and the leading cause of mortality among women worldwide. Tumor metastasis is an important cause of poor prognosis. Determining the exact mechanisms of metastasis and potential targeted therapies is urgently needed. Junctional adhesion molecule 3 (JAM3) is an important member of the TJ tight junction (TJ) family, and its biological function in cervical cancer needs to be further clarified. We found that JAM3 was highly expressed in cervical cancer patients with lymph node metastasis and that high expression of JAM3 promoted cervical cancer cell metastasis both in vitro and in vivo. In addition, overexpression of JAM3 induces epithelial-mesenchymal transition (EMT). Moreover, silencing JAM3 suppressed cervical cancer cell migration and invasion in vitro. Finally, JAM3 overexpression activated the HIF-1α/VEGFA pathway. In conclusion, our results suggested that JAM3 promotes cervical cancer cell migration and invasion by activating the HIF-1α/VEGFA pathway. JAM3 may be a promising biomarker and effective therapeutic target for cervical cancer.

A Multifunctional Scaffold for Bone Infection Treatment by Delivery of microRNA Therapeutics Combined With Antimicrobial Nanoparticles

Treating bone infections and ensuring bone repair is one of the greatest global challenges of modern orthopedics, made complex by antimicrobial resistance (AMR) risks due to long-term antibiotic treatment and debilitating large bone defects following infected tissue removal. An ideal multi-faceted solution would will eradicate bacterial infection without long-term antibiotic use, simultaneously stimulating osteogenesis and angiogenesis. Here, a multifunctional collagen-based scaffold that addresses these needs by leveraging the potential of antibiotic-free antimicrobial nanoparticles (copper-doped bioactive glass, CuBG) to combat infection without contributing to AMR in conjunction with microRNA-based gene therapy (utilizing an inhibitor of microRNA-138) to stimulate both osteogenesis and angiogenesis, is developed. CuBG scaffolds reduce the attachment of gram-positive bacteria by over 80%, showcasing antimicrobial functionality. The antagomiR-138 nanoparticles induce osteogenesis of human mesenchymal stem cells in vitro and heal a large load-bearing defect in a rat femur when delivered on the scaffold. Combining both promising technologies results in a multifunctional antagomiR-138-activated CuBG scaffold inducing hMSC-mediated osteogenesis and stimulating vasculogenesis in an in vivo chick chorioallantoic membrane model. Overall, this multifunctional scaffold catalyzes killing mechanisms in bacteria while inducing bone repair through osteogenic and angiogenic coupling, making this platform a promising multi-functional strategy for treating and repairing complex bone infections.

The role of noncoding RNAs in the tumor microenvironment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the leading fatal malignancy worldwide. The tumor microenvironment (TME) can affect the survival, proliferation, migration, and even dormancy of cancer cells. Hypoxia is an important component of the TME, and hypoxia-inducible factor-1α (HIF-1α) is the most important transcriptional regulator. Noncoding RNAs (ncRNAs), including microRNAs (miRNAs), long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs), comprise a large part of the human transcriptome and play an important role in regulating the tumorigenesis of HCC. This review discusses the role of ncRNAs in hepatocarcinogenesis, epithelial-mesenchymal transition (EMT), and angiogenesis in a hypoxic microenvironment, as well as the interactions between ncRNAs and key components of the TME. It further discusses their use as biomarkers and the potential clinical value of drugs, as well as the challenges faced in the future.

Little things with significant impact: miRNAs in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) has developed into one of the most lethal, aggressive, and malignant cancers worldwide. Although HCC treatment has improved in recent years, the incidence and lethality of HCC continue to increase yearly. Therefore, an in-depth study of the pathogenesis of HCC and the search for more reliable therapeutic targets are crucial to improving the survival quality of HCC patients. Currently, miRNAs have become one of the hotspots in life science research, which are widely present in living organisms and are non-coding RNAs involved in regulating gene expression. MiRNAs exert their biological roles by suppressing the expression of downstream genes and are engaged in various HCC-related processes, including proliferation, apoptosis, invasion, and metastasis. In addition, the expression status of miRNAs is related to the drug resistance mechanism of HCC, which has important implications for the systemic treatment of HCC. This paper reviews the regulatory role of miRNAs in the pathogenesis of HCC and the clinical applications of miRNAs in HCC in recent years.

Differential Impact of Intermittent vs. Sustained Hypoxia on HIF-1, VEGF and Proliferation of HepG2 Cells

Obstructive sleep apnea (OSA) is an emerging risk factor for cancer occurrence and progression, mainly mediated by intermittent hypoxia (IH). Systemic IH, a main landmark of OSA, and local sustained hypoxia (SH), a classical feature at the core of tumors, may act separately or synergistically on tumor cells. Our aim was to compare the respective consequences of intermittent and sustained hypoxia on HIF-1, endothelin-1 and VEGF expression and on cell proliferation and migration in HepG2 liver tumor cells. Wound healing, spheroid expansion, proliferation and migration were evaluated in HepG2 cells following IH or SH exposure. The HIF-1α, endothelin-1 and VEGF protein levels and/or mRNA expression were assessed, as were the effects of HIF-1 (acriflavine), endothelin-1 (macitentan) and VEGF (pazopanib) inhibition. Both SH and IH stimulated wound healing, spheroid expansion and proliferation of HepG2 cells. HIF-1 and VEGF, but not endothelin-1, expression increased with IH exposure but not with SH exposure. Acriflavine prevented the effects of both IH and SH, and pazopanib blocked those of IH but not those of SH. Macitentan had no impact. Thus, IH and SH stimulate hepatic cancer cell proliferation via distinct signaling pathways that may act synergistically in OSA patients with cancer, leading to enhanced tumor progression.