Circular RNA circ_0023404 serves as a miR-636 sponge to promote malignant behaviors in cervical cancer cells through upregulation of CYP2S1

Exosomal circKIAA1797 Regulates Cell Progression and Glycolysis by Targeting miR-4429/PBX3 Pathway in Gastric Cancer

In recent years, circular RNAs (circRNAs) are extensively studied in the progression of various types of cancer, while the mechanism of circKIAA1797 is rarely studied in gastric cancer (GC). Hence, this research aimed to investigate the expression of exosomal circKIAA1797 and its biological function in GC cells. Exosomes were extracted from the serum of GC patients and identified by transmission electron microscopy (TEM) and nanoparticle tracking analyzer (NTA). CD81, CD63, Bcl-2, Bax, and pre-leukemia transcription factor 3 (PBX3) protein levels were detected using western blot assay. circKIAA1797, microRNA-4429 (miR-4429), and PBX3 mRNA were determined by quantitative real-time PCR (RT-qPCR). Cell proliferation, migration, invasion, and apoptosis were assessed using colony formation assay, 5-Ethynyl-2'-deoxyuridine (EdU) assay, transwell assay, and flow cytometry assay. Glucose consumption and lactate production levels were examined using glycolysis detection kits. The interaction between miR-4429 and circKIAA1797 or PBX3 was identified using dual-luciferase reporter assay, RNA pull-down assay, and RNA immunoprecipitation (RIP) assay. Xenograft mouse model assay was used to investigate the effect of exosomal circKIAA1797 in vivo. It was found that circKIAA1797 was up-regulated in GC tissues and cells, as well as in the exosomes derived from the serum of GC patients. Silencing of exosomal circKIAA1797 could hamper cell progression and glycolytic metabolism of GC. Mechanically, circKIAA1797 acted as a sponge of miR-4429 to regulate PBX3 expression. Moreover, the knockdown of exosomal circKIAA1797 repressed tumor growth in vivo. Our data demonstrated that knockdown of exosomal circKIAA1797 suppressed GC malignant phenotypes by regulating miR-4429/PBX3 axis, which might offer a promising therapeutic strategy for GC treatment.

Dysregulated Expression Patterns of Circular RNAs in Cancer: Uncovering Molecular Mechanisms and Biomarker Potential

Circular RNAs (circRNAs) are stable, enclosed, non-coding RNA molecules with dynamic regulatory propensity. Their biogenesis involves a back-splicing process, forming a highly stable and operational RNA molecule. Dysregulated circRNA expression can drive carcinogenic and tumorigenic transformation through the orchestration of epigenetic modifications via extensive RNA and protein-binding domains. These multi-ranged functional capabilities have unveiled extensive identification of previously unknown molecular and cellular patterns of cancer cells. Reliable circRNA expression patterns can aid in early disease detection and provide criteria for genome-specific personalized medicine. Studies described in this review have revealed the novelty of circRNAs and their biological ss as prognostic and diagnostic biomarkers.

Identification of expression profiles and prognostic value of RFCs in colorectal cancer

Colorectal cancer (CRC) ranks among the most prevalent cancers globally, with its incidence closely tied to DNA damage. The Replication Factor C (RFC) complexes comprises five protein subunits: RFC1, RFC2, RFC3, RFC4, and RFC5. These RFC complexes play crucial roles in DNA replication, repair pathways, activities post DNA damage, and ATP-dependent processes during DNA synthesis. However, the impact of RFC complexes proteins on CRC prognosis remains unclear. To explore this, we employed a computational analysis approach, utilizing platforms such as the DepMap portal, GEPIA, DAVID Bioinformatics for KEGG pathway analysis, Human Protein Atlas (HPA), STRING, and TIMER. Our results indicate that the mRNA levels of RFC1 and RFC5 were the least expressed among CRC cell lines compared to other RFC complex subunits. Notably, low RFC1 and RFC5 expression was correlated with poor prognosis in terms of CRC patients' overall survival (OS). Immunohistochemical results from the Human Protein Atlas demonstrated medium staining for RFC1, RFC2, and RFC5 in CRC tissues. Furthermore, the low expression of RFC1 and RFC5 showed a significant correlation with high expression levels of miR-26a-5p and miR-636, impacting cell proliferation through mismatch repair, DNA replication, and the nucleotide excision repair pathway. Although the precise functions of RFC1 in cancer are still unknown, our findings suggest that the small-molecule single target, CHEMBL430483, and multiple target molecules could be potential treatments for CRC. In conclusion, the elevated expression of miR-26a-5p and miR-636 targeting RFC1 and RFC5 expression holds promise as a potential biomarker for early-stage CRC detection. These insights provide novel directions and strategies for CRC therapies.

Hsa_circ_0084912 Drives the Progression of Cervical Cancer Via Regulating miR-429/SOX2 Pathway

We focus on hsa_circ_0084912's role in Cervical cancer (CC) and its molecular pathways. In order to determine the expression of Hsa_circ_0084912, miR-429, and SOX2 in CC tissues and cells, Western blotting and quantitative real-time polymerase chain reaction (qRT-PCR) were utilized. Cell counting kit 8 (CCK-8), colony formation and Transwell assays were respectively to analyze CC cell proliferation viability, clone formation ability and migration. RNA immunoprecipitation (RIP) assay and dual-luciferase assay were used to assure the targeting correlation among hsa_circ_0084912/SOX2 and miR-429. By using a xenograft tumor model, the hsa_circ_0084912 impact on CC cell proliferation in vivo was confirmed. Hsa_circ_0084912 and SOX2 expressions were aggrandized, however, miR-429 expression was descended in CC tissues and cells. Silencing hsa_circ_0084912 inhibited cell proliferation, colony formation and migration in vitro of CC, meanwhile reducing growth of tumor in vivo. MiR-429 might be sponged by Hsa_circ_0084912 to control SOX2 expression. Hsa_circ_0084912 knockdown impact on the malignant phenotypes of CC cells was restored by miR-429 inhibitor. Moreover, SOX2 silencing eliminated the promotive effects of miR-429 inhibitors on CC cell malignancies. By raising SOX2 expression by targeting miR-429, hsa_circ_0084912 accelerated the development of CC, offering fresh proof that it is a viable target for CC treatment.

Identification of Novel miRNAs, Targeting Genes, Signaling Pathway, and the Small Molecule for Overcoming Oxaliplatin Resistance of Metastatic Colorectal Cancer

One of the globally common cancers is colorectal cancer (CRC). At present, a surgical approach remains a good option for CRC patients; however, 20% of surgically treated CRC patients experience metastasis. Currently, even the first-line used drug, oxaliplatin, remains inadequate for treating metastatic CRC, and its side effect of neurotoxicity is a major problem when treating CRC. The Gene Omnibus GSE42387 database contains gene expression profiles of parental and oxaliplatin-resistant LoVo cell lines. Differentially expressed genes (DEGs) between parental and oxaliplatin-resistance LoVo cells, protein-protein interactions (PPIs), and a pathway analysis were determined to identify overall biological changes by an online DAVID bioinformatics analysis. The ability of DEGs to predict overall survival (OS) and disease-free survival (DFS) was validated by the SPSS 22.0, using liver metastasis CRC patient samples of GSE41258. The bioinformatics web tools of the GEPIA, the Human Protein Atlas, WebGestalt, and TIMER platforms were used. In total, 218 DEGs were identified, among which 105 were downregulated and 113 were upregulated. After mapping the PPI networks and pathways, 60 DEGs were identified as hub genes (with high degrees). Six genes (TGFB1, CD36, THBS1, FABP1, PCK1, and IRS1) were involved with malaria, PPAR signaling, and the adipocytokine signaling pathway. High expressions of CD36 and PCK1 were associated with the poor survival of CRC patients in the GSE41258 database. We predicted specific micro (mi)RNAs that targeted the 3′ untranslated region (UTR) of PCK1 by using miRWalk. It was found that three miRNAs, viz., miR-7-5p, miR-20a-3p, and miR-636, may be upstream targets of those genes. High expression levels of miR-7-5p, miR-20a-3p, and miR-636 were associated with poor OS of CRC patients, and the small-molecule compound, mersalyl, is a promising drug for treating oxaliplatin-resistant CRC. In conclusion, miR-7-5p miR-20a-3p, and miR-636 targeted the PCK1 biomarker in the PPAR signaling pathway, which is involved in oxaliplatin-resistant CRC. Meanwhile, mersalyl was identified as a potential drug for overcoming oxaliplatin resistance in CRC. Our findings may provide novel directions and strategies for CRC therapies.