MicroRNA-596 is epigenetically inactivated and suppresses prostatic cancer cell growth and migration via regulating Wnt/β-catenin signaling

Deciphering the Enigmatic Influence: Non-Coding RNAs Orchestrating Wnt/β-Catenin Signaling Pathway in Tumor Progression

Dysregulated expression of specific non-coding RNAs (ncRNAs) has been strongly linked to tumorigenesis, cancer progression, and therapeutic resistance. These ncRNAs can act as either oncogenes or tumor suppressors, thereby serving as valuable diagnostic and prognostic markers. Numerous studies have implicated the participation of ncRNAs in the regulation of diverse signaling pathways, including the pivotal Wnt/β-catenin signaling pathway that is widely acknowledged for its pivotal role in embryogenesis, cellular proliferation, and tumor biology control. Recent emerging evidence has shed light on the capacity of ncRNAs to interact with key components of the Wnt/β-catenin signaling pathway, thereby modulating the expression of Wnt target genes in cancer cells. Notably, the activity of this pathway can reciprocally influence the expression levels of ncRNAs. However, comprehensive analysis investigating the specific ncRNAs associated with the Wnt/β-catenin signaling pathway and their intricate interactions in cancer remains elusive. Based on these noteworthy findings, this review aims to unravel the intricate associations between ncRNAs and the Wnt/β-catenin signaling pathway during cancer initiation, progression, and their potential implications for therapeutic interventions. Additionally, we provide a comprehensive overview of the characteristics of ncRNAs and the Wnt/β-catenin signaling pathway, accompanied by a thorough discussion of their functional roles in tumor biology. Targeting ncRNAs and molecules associated with the Wnt/β-catenin signaling pathway may emerge as a promising and effective therapeutic strategy in future cancer treatments.

Transcribed Ultraconserved Regions: New regulators in cancer signaling and potential biomarkers

The ultraconserved regions (UCRs) are 481 genomic elements, longer than 200 bp, 100% conserved in human, mouse, and rat genomes. Usually, coding regions are more conserved, but more than 80% of UCRs are either intergenic or intronic, and many of them produce long non-coding RNAs (lncRNAs). Recently, the deregulated expression of transcribed UCRs (T-UCRs) has been associated with pathological conditions. But, differently from many lncRNAs with recognized crucial effects on malignant cell processes, the role of T-UCRs in the control of cancer cell networks is understudied. Furthermore, the potential utility of these molecules as molecular markers is not clear. Based on this information, the present review aims to organize information about T-UCRs with either oncogenic or tumor suppressor role associated with cancer cell signaling, and better describe T-UCRs with potential utility as prognosis markers. Out of 481 T-UCRs, 297 present differential expression in cancer samples, 23 molecules are associated with tumorigenesis processes, and 12 have more clear potential utility as prognosis markers. In conclusion, T-UCRs are deregulated in several tumor types, highlighted as important molecules in cancer networks, and with potential utility as prognosis markers, although further investigation for translational medicine is still needed.

Exosomal circPRRX1 functions as a ceRNA for miR-596 to promote the proliferation, migration, invasion, and reduce radiation sensitivity of gastric cancer cells via the upregulation of NF-κB activating protein

Exosomes, which are small extracellular vesicles, have been unveiled to carry circular RNAs (circRNAs). CircRNA paired-related homeobox 1 (circPRRX1) can be transferred by exosomes derived from gastric cancer cells. Here, we investigated the activity and mechanism of exosomal circPRRX1 in gastric tumorigenesis and radiation sensitivity. CircPRRX1, microRNA (miR)-596, and NF-κB activating protein (NKAP) were quantified by quantitative real-time PCR and immunoblotting. Cell proliferation, motility, and invasion were detected by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide and transwell assays, respectively. Cell colony formation and survival were assessed by colony formation assays. Dual-luciferase reporter assays were performed to verify the direct relationship between miR-596 and circPRRX1 or NKAP. In-vivo xenograft studies were used to evaluate the role of exosomal circPRRX1 in tumor growth. Our data showed that circPRRX1 expression was elevated in human gastric cancer, and circPRRX1 could be transferred by exosomes from gastric cancer cells. Exosomal circPRRX1 affected cell proliferation, motility, invasion, and radiation sensitivity in vitro and tumor growth in vivo. Mechanistically, circPRRX1 directly regulated miR-596 expression, and exosomal circPRRX1 affected cell biological functions at least in part through miR-596. NKAP was identified as a direct target and functionally downstream effector of miR-596. Exosomal circPRRX1 modulated NKAP expression by acting as a competing endogenous RNA (ceRNA) for miR-596. Our findings suggest a new mechanism, the exosomal circPRRX1/miR-596/NKAP ceRNA crosstalk, in regulating gastric tumorigenesis and radiation sensitivity.