miR-23a-3p Regulates Runx2 to Inhibit the Proliferation and Metastasis of Oral Squamous Cell Carcinoma

MiRNA-related metastasis in oral cancer: moving and shaking

Across the world, oral cancer is a prevalent tumor. Over the years, both its mortality and incidence have grown. Oral cancer metastasis is a complex process involving cell invasion, migration, proliferation, and egress from cancer tissue either by lymphatic vessels or blood vessels. MicroRNAs (miRNAs) are essential short non-coding RNAs, which can act either as tumor suppressors or as oncogenes to control cancer development. Cancer metastasis is a multi-step process, in which miRNAs can inhibit or stimulate metastasis at all stages, including epithelial-mesenchymal transition, migration, invasion, and colonization, by targeting critical genes in these pathways. On the other hand, long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs), two different types of non-coding RNAs, can regulate cancer metastasis by affecting gene expression through cross-talk with miRNAs. We reviewed the scientific literature (Google Scholar, Scopus, and PubMed) for the period 2000-2023 to find reports concerning miRNAs and lncRNA/circRNA-miRNA-mRNA networks, which control the spread of oral cancer cells by affecting invasion, migration, and metastasis. According to these reports, miRNAs are involved in the regulation of metastasis pathways either by directly or indirectly targeting genes associated with metastasis. Moreover, circRNAs and lncRNAs can induce or suppress oral cancer metastasis by acting as competing endogenous RNAs to inhibit the effect of miRNA suppression on specific mRNAs. Overall, non-coding RNAs (especially miRNAs) could help to create innovative therapeutic methods for the control of oral cancer metastases.

MicroRNAs as important players in regulating cancer through PTEN/PI3K/AKT signalling pathways

Cancer being the leading cause of mortality has become a great threat worldwide. Current cancer therapeutics lack specificity and have side effects due to a lack of understanding of the molecular mechanisms and signalling pathways involved in carcinogenesis. In recent years, researchers have been focusing on several signalling pathways to pave the way for novel therapeutics. The PTEN/PI3K/AKT pathway is one of the important pathways involved in cell proliferation and apoptosis, leading to tumour growth. In addition, the PTEN/PI3K/AKT axis has several downstream pathways that could lead to tumour malignancy, metastasis and chemoresistance. On the other hand, microRNAs (miRNAs) are important regulators of various genes leading to disease pathogenesis. Hence studies of the role of miRNAs in regulating the PTEN/PI3K/AKT axis could lead to the development of novel therapeutics for cancer. Thus, in this review, we have focused on various miRNAs involved in the carcinogenesis of various cancer via the PTEN/PI3K/AKT axis.

RUNX2 and Cancer

Runt-related transcription factor 2 (RUNX2) is critical for the modulation of chondrocyte osteoblast differentiation and hypertrophy. Recently discovered RUNX2 somatic mutations, expressional signatures of RUNX2 in normal tissues and tumors, and the prognostic and clinical significance of RUNX2 in many types of cancer have attracted attention and led RUNX2 to be considered a biomarker for cancer. Many discoveries have illustrated the indirect and direct biological functions of RUNX2 in orchestrating cancer stemness, cancer metastasis, angiogenesis, proliferation, and chemoresistance to anticancer compounds, warranting further exploration of the associated mechanisms to support the development of a novel therapeutic strategy. In this review, we focus mainly on critical and recent research developments, including RUNX2's oncogenic activities, by summarizing and integrating the findings on somatic mutations of RUNX2, transcriptomic studies, clinical information, and discoveries about how the RUNX2-induced signaling pathway modulates malignant progression in cancer. We also comprehensively discuss RUNX2 RNA expression in a pancancer panel and in specific normal cell types at the single-cell level to indicate the potential cell types and sites for tumorigenesis. We expect this review to shed light on the recent mechanistical findings and modulatory role of RUNX2 in cancer progression and provide biological information that can guide new research in this field.

GAS5 attenuates the malignant progression of glioma stem-like cells by promoting E-cadherin

It has been widely reported that glioma stem-like cells (GSCs) serve a crucial role in the malignant progression of glioma. In particular, recent studies have reported that long non-coding RNAs (lncRNAs) are closely associated with glioma development. However, the underlying molecular regulatory mechanistic role of GSCs remains poorly understood. The present study established two highly malignant glioma stem-like cell lines from clinical surgical specimens. In these, it was found that the lncRNA growth arrest-specific 5 (GAS5) expression was downregulated in GSCs and high-grade glioma tissues, compared with normal human astrocyte cells (NHAs) and normal brain tissues, respectively, which also showed a positive correlation with patient survival. Functional assays revealed that knocking down GAS5 expression promoted the proliferation, invasion, migration, stemness, and tumorigenicity of GSGs, while suppressing their apoptosis. Mechanistically, GAS5 directly sponged miR-23a, which in turn functioned as an oncogene by inhibiting E-cadherin, through the assays of reverse transcription-quantitative PCR (RT-qPCR) and luciferase reports. In addition, rescue experiments demonstrated that GAS5 could promote the expression and function of E-cadherin in a miR-23a-dependent manner. Collectively, these data suggest that GAS5 functions as a suppressor in GSCs by targeting the miR-23a/E-cadherin axis, which may be a promising therapeutic target against glioma.

Focusing on OB-OC-MΦ Axis and miR-23a to Explore the Pathogenesis and Treatment Strategy of Osteoporosis

Osteoporosis is a bone metabolic disorder characterized by decreased bone density and deteriorated microstructure, which increases the risk of fractures. The imbalance between bone formation and bone resorption results in the occurrence and progression of osteoporosis. Osteoblast-mediated bone formation, osteoclast-mediated bone resorption and macrophage-regulated inflammatory response play a central role in the process of bone remodeling, which together maintain the balance of the osteoblast-osteoclast-macrophage (OB-OC-MΦ) axis under physiological conditions. Bone formation and bone resorption disorders caused by the imbalance of OB-OC-MΦ axis contribute to osteoporosis. Many microRNAs are involved in the regulation of OB-OC-MΦ axis homeostasis, with microRNA-23a (miR-23a) being particularly crucial. MiR-23a is highly expressed in the pathological process of osteoporosis, which eventually leads to the occurrence and further progression of osteoporosis by inhibiting osteogenesis, promoting bone resorption and inflammatory polarization of macrophages. This review focuses on the role and mechanism of miR-23a in regulating the OB-OC-MΦ axis to provide new clinical strategies for the prevention and treatment of osteoporosis.