Effect of miR-515-5p on Proliferation and Drug Sensitivity of Retinoblastoma Cells

circSLTM knockdown attenuates chondrocyte inflammation, apoptosis and ECM degradation in osteoarthritis by regulating the miR-515-5p/VAPB axis

Osteoarthritis (OA) is a prevalent joint disorder characterized by cartilage degeneration. Circular RNAs (circRNAs) have emerged as pivotal players in OA progression, orchestrating various biological processes such as proliferation, apoptosis, inflammation, and extracellular matrix (ECM) reorganization. Among these circRNAs, circSLTM exhibits aberrant expression in OA, yet its precise regulatory mechanism remains elusive. This study aimed to elucidate the regulatory mechanisms of circSLTM in OA pathogenesis, with a focus on its role as a competing endogenous RNA (ceRNA). Human cartilage tissues were procured from both OA patients and non-OA individuals, while human chondrocyte cells were subjected to lipopolysaccharide (LPS) treatment to mimic OA-like conditions. Our findings revealed upregulation of circSLTM in OA patients and LPS-treated chondrocytes. Loss-of-function assays were conducted, demonstrating that silencing circSLTM via shRNAs mitigated LPS-induced effects on chondrocytes, as evidenced by enhanced proliferation, reduced apoptosis, and inflammatory factors, and altered expression of extracellular matrix proteins. Further exploration into the regulatory mechanism of circSLTM unveiled its interaction with microRNA-515-5p (miR-515-5p) to modulate vesicle-associated membrane protein (VAPB) expression in chondrocytes. VAPB, also upregulated in OA, was positively regulated by circSLTM. Rescue assays corroborated that VAPB overexpression reinstated the protective effects of circSLTM knockdown on LPS-treated chondrocytes. Moreover, concurrent knockdown of both circSLTM and VAPB demonstrated synergistic protection against LPS-induced chondrocyte injury. Additionally, we delineated that LPS triggered the activation of the NF-κB pathway in chondrocytes, which was counteracted by circSLTM silencing. To assess the effects of circSLTM on OA in vivo, anterior cruciate ligament transection (ACLT) mouse models were established, revealing that circSLTM deficiency ameliorated cartilage defects in vivo. In conclusion, circSLTM exacerbates osteoarthritis progression by orchestrating the miR-515-5p/VAPB axis and activating the NF-κB pathway, providing novel insights for targeted therapy in OA management.

Bioinformatics analysis proposes a possible role for long noncoding RNA MIR17HG in retinoblastoma

BACKGROUND

Retinoblastoma (RB) is the most common prevalent intraocular malignancy among infants and children, particularly in underdeveloped countries. With advancements in genomics and transcriptomics, noncoding RNAs have been increasingly utilized to investigate the molecular pathology of diverse diseases.

AIMS

This study aims to establish the competing endogenous RNAs network associated with RB, analyse the function of mRNAs and lncRNAs, and finds the relevant regulatory network.

METHODS AND RESULTS

This study establishes a network of competing endogenous RNAs by Spearman correlation analysis and prediction based on RB patients and healthy children. Enrichment analyzes based on Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes are conducted to analyze the potential biological functions of lncRNA and mRNA networks. Weighted gene co-expression network analysis (WGCNA) is employed to identify gene cluster modules exhibiting the strongest correlation with RB. The results indicate a significant correlation between the lncRNA MIR17HG (R = .73, p = .02) and the RB phenotype. ceRNA networks reveal downstream miRNAs (hsa-mir-425-5p and hsa-mir455-5p) and mRNAs (MDM2, IPO11, and ITGA1) associated with MIR17Hg. As an inhibitor of the p53 signaling pathway, MDM2 can suppress the development of RB.

CONCLUSION

In conclusion, lncRNAs play a role in RB, and the MIR17HG/hsa-mir-425-5p/MDM2 pathway may contribute to RB development by inhibiting the p53 signaling pathway.

From resistance to resilience: Uncovering chemotherapeutic resistance mechanisms; insights from established models

Despite the tremendous advances in cancer treatment, resistance to chemotherapeutic agents impedes higher success rates and accounts for major relapses in cancer therapy. Moreover, the resistance of cancer cells to chemotherapy is linked to low efficacy and high recurrence of cancer. To stand up against chemotherapy resistance, different models of chemotherapy resistance have been established to study various molecular mechanisms of chemotherapy resistance. Consequently, this review is going to discuss different models of induction of chemotherapy resistance, highlighting the most common mechanisms of cancer resistance against different chemotherapeutic agents, including overexpression of efflux pumps, drug inactivation, epigenetic modulation, and epithelial-mesenchymal transition. This review aims to open a new avenue for researchers to lower the resistance to the existing chemotherapeutic agents, develop new therapeutic agents with low resistance potential, and establish possible prognostic markers for chemotherapy resistance.

miRNAs as potential game-changers in retinoblastoma: Future clinical and medicinal uses

Retinoblastoma (RB) is a rare tumor in children, but it is the most common primitive intraocular malignancy in childhood age, especially those below three years old. The RB gene (RB1) undergoes mutations in individuals with RB. Although mortality rates remain high in developing countries, the survival rate for this type of cancer is greater than 95-98% in industrialized countries. However, it is lethal if left untreated, so early diagnosis is essential. As a non-coding RNA, miRNA significantly impacts RB development and treatment resistance because it can control various cellular functions. In this review, we illustrate the recent advances in the role of miRNAs in RB. That includes the clinical importance of miRNAs in RB diagnosis, prognosis, and treatment. Moreover, the regulatory mechanisms of miRNAs in RB and therapeutic interventions are discussed.

Knocking down Trim47 ameliorated sevoflurane-induced neuronal cell injury and cognitive impairment in rats

Sevoflurane (SEV), usually causing neuronal damage and cognitive dysfunction, is one of the most commonly used anesthetics in clinical practice. However, the function of Trim47 in SEV-induced neuronal impairment remains elusive. The aim of this study was to study the effect of knocking down Trim47 on the nerve injury induced by SEV. Nerve injury was induced in rats by 3% SEV, and H19-7 was used to establish a pathological model, and sh-Trim47 was transfected into H19-7 to study the function of Trim47. The effects of SEV on the expression of Trim47 in the hippocampus and cognitive function of rats were studied by neurological function score and Moris water maze (MWM). The mRNA and protein expression of TNF-α, IL-1β and IL-6 in the cells, along with the neuronal apoptosis in the hippocampus of rats in each group were studied by TUNEL or WB. Flow cytometry was used to study the effect of knockdown of Trim47 on cell apoptosis. CCK-8 was used to detect cell viability of H19-7 cells. Finally, the potential signaling pathway affected by knockdown of Trim47 after abrogation of SEV induction was investigated by WB. The results showed that, knockdown of Trim47 ameliorated SEV-induced neurological damage and cognitive deficits, inflammation and neuronal cell apoptosis in rats, and promoted hippocampal neuronal activity. Knockdown of Trim47 can inhibit the NF-κB signaling pathway and improve neuronal cell damage and cognitive impairment induced by SEV in neonatal rats by regulating NF-κB signaling pathway, alleviating inflammatory response, and inhibiting neuronal apoptosis.

miR-515-5p suppresses trophoblast cell invasion and proliferation through XIAP regulation in preeclampsia

MicroRNAs (miRNAs) are non-coding small RNA molecules that can be secreted into the circulation and which exist in remarkably stable forms. Circulating miRNAs regulate numerous biological process and are aberrantly expressed in pathological conditions. Differentially expressed circulating miRNAs have received attention as potential biomarkers for many diseases. In this study, we revealed that miR-515-5p was significantly upregulated in maternal serum from preeclampsia patients in comparison to normal pregnant women. Bioinformatics prediction and a dual-luciferase reporter gene assay revealed that miR-515-5p directly targets the X-linked inhibitor of apoptosis protein (XIAP) 3'-untranslated region. In addition, the overexpression of miR-515-5p inhibited the proliferation and invasion of HTR-8/SVneo trophoblast cells. The decreased XIAP expression and reduced epithelial-mesenchymal transition (EMT) were observed in the preeclamptic placenta. Collectively, miR-515-5p may play critical roles in the pathogenesis of preeclampsia through suppression of XIAP, and serum miR-515-5p may act as a potential biomarker for preeclampsia.

Carnosol alleviates sevoflurane-induced cognitive dysfunction by mediating NF-κB pathway in aged rats

Postoperative Cognitive Dysfunction (POCD) is a neurological disorder of unconsciousness due to cognitive regression after surgical anesthesia. However, the specific mechanism has not yet been clarified. Sevoflurane (SEV) is one of the most commonly used anesthetics in clinical practice, and how SEV mediates the generation of POCD is unclear. Carnosol, a natural ingredient, has been reported to have various beneficial effects such as anti-inflammatory, immune enhancement, and so forth, but how it ameliorates SEV-mediated neurotoxicity remains unclear. This study aimed to induce a POCD model in aged rats by SEV and to elucidate how Carnosol ameliorated SEV-mediated neurotoxicity. The effects of Carnosol on the expression of inflammatory factors in rat hippocampus mediated by SEV were determined by enzyme-linked immunoassay and polymerase chain reaction experiments; the effects of Carnosol on the expressions of Iba-1 and glial fibrillary acidic protein after SEV-mediated activation of rat microglia were clarified by immunofluorescence and Western blotting (WB); The effects of Carnosol on SEV-mediated neuronal apoptosis were studied by terminal deoxynucleotidyl transferase dUTP nick end labeling and WB; the specific signaling pathways regulated by Carnosol were elucidated by WB. The results showed that Carnosol can improve the cognitive dysfunction and reduce neuroinflammation in aged rats induced by SEV; Carnosol can reduce the activation of microglia and inhibit neuronal apoptosis in aged rats induced by SEV; Carnosol can phosphorylate p65 and nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha regulates the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway. Carnosol can attenuate SEV-induced neuroinflammation, prevent microglial activation and inhibit neuronal apoptosis by modulating the NF-κB pathway.

CircKIF4A enhances osteosarcoma proliferation and metastasis by sponging MiR-515-5p and upregulating SLC7A11

BACKGROUND

Circular RNAs (circRNAs) are forms of non-coding RNAs that have crucial roles in regulation of various biological processes of several malignant tumors. circKIF4A is closely associated with malignant progression of a variety of cancers. However, the molecular mechanisms as well as roles of circKIF4A in osteosarcoma (OS) have not yet been clearly elucidated.

METHODS

We evaluated the expression of circKIF4A in OS. Colony-formation, cell counting kit-8 (CCK-8), transwell and mice metastasis model assays were done to explore the roles of circKIF4A in vitro and in vivo. TargetScan database, double luciferase, quantitative reverse transcription polymerase chain reaction analysis (RT-qPCR), and RNA immunoprecipitation (RIP) were done to investigate the associated molecular mechanisms.

RESULTS

In both OS cells and tissues, circKIF4A (hsa_circ_0007255) was found to be upregulated. In vitro and in vivo, circKIF4A knockdown markedly suppressed OS proliferation as well as metastasis. circKIF4A enhanced OS growth as well as metastasis by sponging miR-515-5p and by upregulating SLC7A11.

CONCLUSIONS

We identified the biological significance of the circKIF4A-miR-515-5p-SLC7A11 axis in OS cell proliferation and metastasis, which is important in OS monitoring and treatment. More studies on circKIF4A will inform on the diagnostic markers for early OS screening.

Ex Vivo Infection of Human Placental Explants by Trypanosoma cruzi Reveals a microRNA Profile Similar to That Seen in Trophoblast Differentiation

Congenital Chagas disease, caused by the protozoan parasite Trypanosoma cruzi, is responsible for 22.5% of new cases each year. However, placental transmission occurs in only 5% of infected mothers and it has been proposed that the epithelial turnover of the trophoblast can be considered a local placental defense against the parasite. Thus, Trypanosoma cruzi induces cellular proliferation, differentiation, and apoptotic cell death in the trophoblast, which are regulated, among other mechanisms, by small non-coding RNAs such as microRNAs. On the other hand, ex vivo infection of human placental explants induces a specific microRNA profile that includes microRNAs related to trophoblast differentiation such as miR-512-3p miR-515-5p, codified at the chromosome 19 microRNA cluster. Here we determined the expression validated target genes of miR-512-3p and miR-515-5p, specifically human glial cells missing 1 transcription factor and cellular FLICE-like inhibitory protein, as well as the expression of the main trophoblast differentiation marker human chorionic gonadotrophin during ex vivo infection of human placental explants, and examined how the inhibition or overexpression of both microRNAs affects parasite infection. We conclude that Trypanosoma cruzi-induced trophoblast epithelial turnover, particularly trophoblast differentiation, is at least partially mediated by placenta-specific miR-512-3p and miR-515-5p and that both miRNAs mediate placental susceptibility to ex vivo infection of human placental explants. Knowledge about the role of parasite-modulated microRNAs in the placenta might enable their use as biomarkers, as prognostic and therapeutic tools for congenital Chagas disease in the future.

LncRNA HOTAIR facilitates proliferation and represses apoptosis of retinoblastoma cells through the miR-20b-5p/RRM2/PI3K/AKT axis

Purpose

Retinoblastoma (RB) represents an adolescent eye malignancy. Long non-coding RNA (LncRNA) HOTAIR shows aberrant expression in many malignancies. This research investigated the mechanism of HOTAIR in RB.

Methods

Normal retinal cell lines (ARPE-19 and RPE-1) and RB cell lines (ORB50, Y79, HXO-RB44, and WERI-RB) were selected for detection of HOTAIR expression by qRT-PCR. sh-HOTAIR was delivered into Y79 and HXO-RB44 cells. Cell-cycle distribution, proliferation, and apoptosis were detected by CCK-8 assay and flow cytometry. Binding relationships among HOTAIR, miR-20b-5p, and RRM2 were confirmed using dual-luciferase assay. Roles of miR-20b-5p and RRM2 in RB cell-cycle distribution, proliferation, and apoptosis were ascertained by functional rescue experiments. Murine model of xenograft tumor was established, followed by detection of tumor growth and counting of Ki67-positive cells. Expressions of proliferation- and apoptosis-associated proteins and PI3K/AKT pathway-related proteins were determined by Western blot.

Results

HOTAIR was elevated in RB cells relative to that in normal retinal cells and showed relatively high expression in Y79 and HXO-RB44 cells. sh-HOTAIR induced RB cell-cycle arrest, restrained proliferation, and strengthened apoptosis. HOTAIR functioned as the ceRNA of miR-20b-5p and targeted RRM2. RB cells had poorly-expressed miR-20b-5p and highly-expressed RRM2. miR-20b-5p downregulation or RRM2 overexpression facilitated RB cell-cycle and proliferation, suppressed apoptosis, and reversed the protective effect of sh-HOTAIR on RB. sh-HOTAIR reduced tumor growth and Ki67-positive cells in vivo and inactivated PI3K/AKT pathway.

Conclusion

LncRNA HOTAIR upregulated RRM2 by competitively binding to miR-20b-5p and activated PI3K/AKT pathway, thereby facilitating proliferation and repressing apoptosis of RB cells.

Targeting of MAD2L1 by miR-515-5p involves the regulation of cell cycle arrest and apoptosis of colorectal cancer cells

Although many previous studies have found that the mitotic arrest deficient 2-like 1 (MAD2L1) protein contributes to the proliferation of colorectal cancer (CRC) cells, but the upstream mechanism of MAD2L1 is still largely elusive. This study aimed to explore the miRNAs upstream of MAD2L1 to improve our understanding of the mechanism of the MAD2L1 gene in CRC. The upstream target miRNAs (miR-515-5p) of MAD2L1 were predicted by the online databases miRWalk, miRDIP and TargetScan. Quantitative real-time PCR (qRT-PCR) was used to detect the expression level of miR-515-5p in human CRC tissues. The targeting relationship between miR-515-5p and MAD2L1 was tested by dual luciferase reporter gene assays. The effects of miR-515-5p on the biological behaviors of CRC cells by regulating MAD2L1 expression were verified by qRT-PCR, western blot, CCK-8, and flow cytometry. The results showed that miR-515-5p was a highly reliable upstream miRNA of the MAD2L1 gene. As an upstream target miRNA of MAD2L1, miR-515-5p was lowly expression in CRC tissues. The overexpression of miR-515-5p could inhibit the proliferation of CRC cells and induce cell cycle arrest at the G1 phase leading to cell apoptosis. However, MAD2L1 gene overexpression could reverse the effects of miR-515-5p overexpression on the biological behaviors of CRC cells above. This study illustrated that miR-515-5p can inhibit proliferation and induce G1 phase arrest leading to apoptosis in CRC cells. The mechanism underlying this phenomenon may be related to the negative targeted regulation of MAD2L1. This article is protected by copyright. All rights reserved.

Oncogenic Role of Exosomal Circular and Long Noncoding RNAs in Gastrointestinal Cancers

Circular RNAs (circRNAs) and long noncoding RNAs (lncRNAs) are differentially expressed in gastrointestinal cancers. These noncoding RNAs (ncRNAs) regulate a variety of cellular activities by physically interacting with microRNAs and proteins and altering their activity. It has also been suggested that exosomes encapsulate circRNAs and lncRNAs in cancer cells. Exosomes are then discharged into the extracellular environment, where they are taken up by other cells. As a result, exosomal ncRNA cargo is critical for cell-cell communication within the cancer microenvironment. Exosomal ncRNAs can regulate a range of events, such as angiogenesis, metastasis, immune evasion, drug resistance, and epithelial-to-mesenchymal transition. To set the groundwork for developing novel therapeutic strategies against gastrointestinal malignancies, a thorough understanding of circRNAs and lncRNAs is required. In this review, we discuss the function and intrinsic features of oncogenic circRNAs and lncRNAs that are enriched within exosomes.

Clues for Improving the Pathophysiology Knowledge for Endometriosis Using Plasma Micro-RNA Expression

The pathophysiology of endometriosis remains poorly understood. The aim of the present study was to investigate functions and pathways associated with the various miRNAs differentially expressed in patients with endometriosis. Plasma samples of the 200 patients from the prospective "ENDO-miRNA" study were analyzed and all known human miRNAs were sequenced. For each miRNA, sensitivity, specificity, and ROC AUC values were calculated for the diagnosis of endometriosis. miRNAs with an AUC ≥ 0.6 were selected for further analysis. A comprehensive review of recent articles from the PubMed, Clinical Trials.gov, Cochrane Library, and Web of Science databases was performed to identify functions and pathways associated with the selected miRNAs. In total, 2633 miRNAs were found in the patients with endometriosis. Among the 57 miRNAs with an AUC ≥ 0.6: 20 had never been reported before; one (miR-124-3p) had previously been observed in endometriosis; and the remaining 36 had been reported in benign and malignant disorders. miR-124-3p is involved in ectopic endometrial cell proliferation and invasion and plays a role in the following pathways: mTOR, STAT3, PI3K/Akt, NF-κB, ERK, PLGF-ROS, FGF2-FGFR, MAPK, GSK3B/β-catenin. Most of the remaining 36 miRNAs are involved in carcinogenesis through cell proliferation, apoptosis, and invasion. The three main pathways involved are Wnt/β-catenin, PI3K/Akt, and NF-KB. Our results provide evidence of the relation between the miRNA profiles of patients with endometriosis and various signaling pathways implicated in its pathophysiology.

Cyclophosphamide inhibits Pax5 methylation to regulate the growth of retinoblastoma via the Notch1 pathway

Retinoblastoma (Rb) is the most common intraocular malignant tumor in infants. Here, we investigated the function and mechanism of cyclophosphamide (CTX) in the development of Rb. Real-time quantitative polymerase chain reaction (RT-qPCR) results showed that paired box protein 5 (Pax5) expression was down-regulated in Rb tissues and cell lines. Methylation-specific PCR (MSP) results showed that the methylation level of Pax5 was up-regulated in Rb. After treatment with CTX, the Pax5 expression in Rb cell lines was increased significantly. The methylation of Pax5 and the expression of DNA methyltransferases (DNMTs) were down-regulated in the CTX group. Cyclophosphamide inhibited cell proliferation, migration, and invasion, promoted cell apoptosis via the Notch1 pathway. DNA methyltransferase inhibitor SGI-1027 had synergistic effects with CTX. Paired box protein 5 siRNA was transfected into Y79 cells treated with CTX. The expression of DNMTs, Pax5, the Notch1 pathway and apoptosis marker protein was detected by Western blotting, and changes in cell behavior were detected, respectively. Results showed that knockdown of Pax5 reversed the effects of CTX. Moreover, the Notch1 activator Valproic acid (VPA) abolished the inhibitory effects of CTX on Rb development. Moreover, CTX inhibited tumor growth in nude mice. These findings demonstrated that CTX up-regulated Pax5 expression by down-regulating DNMTs expression, and then inhibited the Notch1 signaling pathway activation and Rb growth.

Long non-coding RNA PROX1-AS1 knockdown upregulates microRNA-519d-3p to promote chemosensitivity of retinoblastoma cells via targeting SOX2

OBJECTIVE

Long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) participate in tumor progression, while the role of PROX1-antisense RNA1 (PROX1-AS1) sponging miR-519d-3p in retinoblastoma (RB) remains largely unknown. We aim to explore the effect of the PROX1-AS1/miR-519d-3p/sex determining region Y-box 2 (SOX2) in chemosensitivity of RB cells.

METHODS

Expression of PROX1-AS1, miR-519d-3p and SOX2 in RB tissues and cells was determined. The drug-resistant cell lines were established and respectively intervened with PROX1-AS1 or miR-519d-3p expression to explore their roles in drug resistance and malignant behaviors of the drug-resistant cells. The binding relationships between PROX1-AS1 and miR-519d-3p, and between miR-519d-3p and SOX2 were evaluated.

RESULTS

PROX1-AS1 and SOX2 were upregulated while miR-519d-3p was downregulated in RB tissues and cells, especially in drug-resistant cells. The PROX1-AS1 inhibition or miR-519d-3p elevation suppressed the drug resistance, proliferation, migration and invasion, and promoted apoptosis of the drug-resistant RB cells. Moreover, PROX1-AS1 sponged miR-519d-3p and miR-519d-3p targeted SOX2.

CONCLUSION

PROX1-AS1 knockdown upregulates miR-519d-3p to promote chemosensitivity of RB cells via targeting SOX2.

miR-130a-3p Enhances the Chemosensitivity of Y79 Retinoblastoma Cells to Vincristine by Targeting PAX6 Expression

PURPOSE

Chemoresistance remains the primary obstacle threatening the prognosis of retinoblastoma (RB). microRNAs (miRNAs) are acknowledged as critical regulators of drug resistance. This study explored the molecular mechanism of miR-130a-3p affecting the chemosensitivity of RB to vincristine (VCR).

METHODS

miR-130a-3p expression of human retinal astrocytes and RB cell lines (Y79, WERI-Rb-1, SO-Rb50, and SO-Rb70) was detected using RT-qPCR. VCR-resistant RB cell line Y79/VCR was induced. miR-130a-3p expression of Y79/VCR cell line and its corresponding parental cell line was detected. Y79/VCR cells were subjected to miR-130a-3p overexpression treatment. The cell proliferation was measured using MTT assay, and the IC50 value and drug resistance index were examined using CCK-8 assay. The targeting relationship between miR-130a-3p and PAX6 was predicted through bioinformatics analysis and verified using dual-luciferase assay. Functional rescue experiments were conducted to confirm the role of PAX6 in chemosensitivity of RB cells. The effect of miR-130a-3p on tumorigenesis and VCR sensitivity was observed in vivo.

RESULTS

miR-130a-3p was downregulated in VCR-resistant RB cells. Overexpression of miR-130a-3p repressed the proliferation of Y79/VCR cells and enhanced chemosensitivity. miR-130a-3p targeted PAX6 expression. Overexpression of PAX6 reversed the effect of miR-130a-3p on chemosensitivity of Y79/VCR cells. Overexpression of miR-130a-3p suppressed tumor growth and reduced VCR resistance in vivo.

CONCLUSIONS

miR-130a-3p enhanced the chemosensitivity of Y79 RB cells to VCR by targeting PAX6 expression.