LncRNA CCDC26 Interacts with CELF2 Protein to Enhance Myeloid Leukemia Cell Proliferation and Invasion via the circRNA_ANKIB1/miR-195-5p/PRR11 Axis

LINC01432 binds to CELF2 in newly diagnosed multiple myeloma promoting short progression-free survival to standard therapy

Multiple Myeloma (MM) is a highly prevalent and incurable form of cancer that arises from malignant plasma cells, with over 35,000 new cases diagnosed annually in the United States. While there are a growing number of approved therapies, MM remains incurable and nearly all patients will relapse and exhaust all available treatment options. Mechanisms for disease progression are unclear and in particular, little is known regarding the role of long non-coding RNAs (lncRNA) in mediating disease progression and response to treatment. In this study, we used transcriptome sequencing to compare newly diagnosed MM patients who had short progression-free survival (PFS) to standard first-line treatment (PFS < 24 months) to patients who had prolonged PFS (PFS > 24 months). We identified 157 differentially upregulated lncRNAs with short PFS and focused our efforts on characterizing the most upregulated lncRNA, LINC01432. We investigated LINC01432 overexpression and CRISPR/Cas9 knockdown in MM cell lines to show that LINC01432 overexpression significantly increases cell viability and reduces apoptosis, while knockdown significantly reduces viability and increases apoptosis, supporting the clinical relevance of this lncRNA. Next, we used individual-nucleotide resolution cross-linking immunoprecipitation with RT-qPCR to show that LINC01432 directly interacts with the RNA binding protein, CELF2. Lastly, we showed that LINC01432-targeted locked nucleic acid antisense oligonucleotides reduce viability and increases apoptosis. In summary, this fundamental study identified lncRNAs associated with short PFS to standard NDMM treatment and further characterized LINC01432, which inhibits apoptosis.

LncRNA MIR181A2HG negatively regulates human keratinocytes proliferation by binding SRSF1

Psoriasis is a common chronic inflammatory skin disease. Abnormal proliferation of keratinocytes plays an important role in the pathogenesis of psoriasis. Long non-coding RNAs (lncRNAs) are involved in the regulation of a variety of cell biological processes. The purpose of this study was to investigate the potential role of lncRNA MIR181A2HG in the proliferation of human keratinocytes. qRT-PCR and Western blotting were performed to measure the expression levels of MIR181A2HG, SRSF1, KRT6, and KRT16 in tissue specimens and HaCaT keratinocytes. The effects of MIR181A2HG on HaCaT keratinocytes proliferation were evaluated using Cell Counting Kit-8 (CCK-8) assays, 5-Ethynyl-2'-deoxyuridine (EdU) incorporation, and cell-cycle assays. RNA pulldown-mass spectrometry (MS) was applied to identify the proteins interacting with MIR181A2HG. RNA pull-down-Western blotting and RNA immunoprecipitation coupled with real-time quantitative reverse transcription-PCR (RIP-qRT-PCR) assays were used to determine the interactions between MIR181A2HG and its RNA-binding proteins (RBPs). MIR181A2HG was down-regulated in psoriasis tissues. MIR181A2HG overexpression induced G0/G1 and G2/M phase cell cycle arrest and decreased the protein levels of KRT6, KRT16, Cyclin D1, CDK4, and Cyclin A2 in HaCaT keratinocytes. MIR181A2HG knockdown showed the opposite effect. By using RNA pulldown-MS, 356 proteins were identified to interact with MIR181A2HG potentially. Bioinformatics analysis showed that NOP56 and SRSF1 may be RNA binding proteins (RBPs) that may be interact with MIR181A2HG. Furthermore, by using RNA pull-down-Western blotting and RIP-qRT-PCR, SRSF1 was determined to interact with MIR181A2HG. Moreover, silencing of SRSF1 inhibited keratinocytes proliferation, which could be reversed with the knockdown of MIR181A2HG. Our findings indicated that MIR181A2HG can negatively regulate HaCaT keratinocytes proliferation by binding SRSF1, suggesting that MIR181A2HG and SRSF1 may serve as potential targets for the treatment of psoriasis.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10616-024-00621-6.

Proline-rich 11 (PRR11) promotes the progression of cutaneous squamous cell carcinoma by activating the EGFR signaling pathway

Cutaneous squamous cell carcinoma (cSCC) is one of the most common skin malignancies, and its incidence rate is increasing worldwide. Proline-rich 11 (PRR11) has been reported to be involved in the occurrence and development of various tumors. However, the role of PRR11 in cSCC remains unknown. In the present study, we observed upregulated expression of PRR11 in cSCC tissues and cell lines. Knockdown of PRR11 in the cSCC cell lines A431 and SCL-1 inhibited cell proliferation by inducing cell cycle arrest during the G1/S phase transition, promoted cell apoptosis, and reduced cell migration and invasion in vitro. Conversely, overexpression of PRR11 promoted cell proliferation, decreased cell apoptosis, and enhanced cell migration and invasion. PRR11 knockdown also inhibited cSCC tumor growth in a mouse xenograft model. Mechanistic investigations by RNA sequencing revealed that 891 genes were differentially expressed genes between cells with PRR11 knockdown and control cells. Enrichment analysis of different genes showed that the epidermal growth factor receptor (EGFR) signaling pathway was the top enriched pathway. We further validated that PRR11 induced EGFR pathway activity, which contributed to cSCC progression. These data suggest that PRR11 may serve as a novel therapeutic target in cSCC.

Advances in targeting of miR‑10‑associated lncRNAs/circRNAs for the management of cancer (Review)

With advancements in sequencing technologies, an increasing number of aberrantly expressed long-non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) have been identified in various types of cancer. lncRNAs and circRNAs are now well-established tumor-influencing factors in cancer, driving not only tumor proliferation and invasion, but also cancer progression, drug resistance and metastatic recurrence. The majority of lncRNAs and circRNAs influence cancer progression by targeting microRNAs (miRNAs/miRs). miR-10a and miR-10b, key members of the miR-10 family, have been shown to play important regulatory roles in cell proliferation, differentiation to cancer progression, and development. Manual evaluation and grouping according to different types of competing endogenous RNA and tumor was performed. The review outlined the current state of knowledge on the regulation of miR-10 family-related lncRNAs and circRNAs. The involvement of lncRNAs and circRNAs in the biogenesis, maturation and function of malignant tumors through the miR-10 family, and the key gene targets and signaling cascades that lncRNAs and circRNAs regulate through the miR-10 family were summarized. Based on the findings of this review, it can be hypothesized that lncRNAs and circRNAs targeting the miR-10 family may serve as diagnostic/prognostic markers and/or therapeutic targets for the management of cancer.

Integrated analysis of the lncRNA-miRNA-mRNA network based on competing endogenous RNA in atrial fibrillation

Objective

Long non-coding RNAs (lncRNAs) play pivotal roles in the transcriptional regulation of atrial fibrillation (AF) by acting as competing endogenous RNAs (ceRNAs). In the present study, the expression levels of lncRNAs of sinus rhythm (SR) patients and AF patients were investigated with transcriptomics technology, and the lncRNA-miRNA-mRNA network based on the ceRNA theory in AF was elaborated.

Methods

Left atrial appendage (LAA) tissues were obtained from patients with valvular heart disease during cardiac surgery, and they were divided into SR and AF groups. The expression characterizations of differentially expressed (DE) lncRNAs in the two groups were revealed by high-throughput sequencing methods. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed, and the lncRNA-miRNA-mRNA-mediated ceRNA network was constructed.

Results

A total of differentially expressed 82 lncRNAs, 18 miRNAs, and 495 mRNAs in human atrial appendage tissues were targeted. Compared to SR patients, the following changes were found in AF patients: 32 upregulated and 50 downregulated lncRNAs; 7 upregulated and 11 downregulated miRNAs; and 408 upregulated and 87 downregulated mRNAs. A lncRNA-miRNA-mRNA network was constructed, which included 44 lncRNAs, 18 miRNAs, and 347 mRNAs. qRT-PCR was performed to verify these findings. GO and KEGG analyses suggested that inflammatory response, chemokine signaling pathway, and other biological processes play important roles in the pathogenesis of AF. Network analysis based on the ceRNA theory identified that lncRNA XR_001750763.2 and Toll-like receptor 2 (TLR2) compete for binding to miR-302b-3p. In AF patients, lncRNA XR_001750763.2 and TLR2 were upregulated, and miR-302b-3p was downregulated.

Conclusion

We identified a lncRNA XR_001750763.2/miR-302b-3p/TLR2 network based on the ceRNA theory in AF. The present study shed light on the physiological functions of lncRNAs and provided information for exploring potential treatments for AF.

PRR11 in Malignancies: Biological Activities and Targeted Therapies

Proline rich 11 (PRR11), initially renowned for its relevance with cell-cycle progression, is a proline-rich protein coding gene in chromosome 17q22-23. Currently, accumulating studies have demonstrated that PRR11 plays a critical role in cellular proliferation, colony formation, migration, invasion, cell-cycle progression, apoptosis, autophagy and chemotherapy resistance via multiple signaling pathways and biological molecules in several solid tumors. In particular, PRR11 also serves as a promising prognostic indicator in a limited number of human cancers, gradually manifesting its potential application for targeted therapies. In this review, we summarize functional activities, related signaling pathways and biological molecules of PRR11 in various malignancies and generalize potential application of PRR11 for targeted therapies, thereby contributing to further exploration of PRR11 in cancer treatment.

Targeting lncRNA/Wnt axis by flavonoids: A promising therapeutic approach for colorectal cancer

Despite the dramatic advances in our understanding of the etiology of colorectal cancer (CRC) in recent decades, effective therapeutic strategies are still urgently needed. Oncogenic mutations in the Wnt/β-Catenin pathway are hallmarks of CRC. Moreover, long non-coding RNAs (lncRNAs) as molecular managers are involved in the initiation, progression, and metastasis of CRC. Therefore, it is important to further explore the interaction between lncRNAs and Wnt/β-Catenin signaling pathway for targeted therapy of CRC. Natural phytochemicals have not toxicity and can target carcinogenesis-related pathways. Growing evidences suggest that flavonoids are inversely associated with CRC risk. These bioactive compounds could target carcinogenesis pathways of CRC and reduced the side effects of anti-cancer drugs. The review systematically summarized the progress of flavonoids targeting lncRNA/Wnt axis in the investigations of CRC, which will provide a promising therapeutic approach for CRC and develop nutrition-oriented preventive strategies for CRC based on epigenetic mechanisms. In the field, more epidemiological and clinical trials are required in the future to verify feasibility of targeting lncRNA/Wnt axis by flavonoids in the therapy and prevention of CRC.

CELF Family Proteins in Cancer: Highlights on the RNA-Binding Protein/Noncoding RNA Regulatory Axis

Post-transcriptional modifications to coding and non-coding RNAs are unquestionably a pivotal way in which human mRNA and protein diversity can influence the different phases of a transcript's life cycle. CELF (CUGBP Elav-like family) proteins are RBPs (RNA-binding proteins) with pleiotropic capabilities in RNA processing. Their responsibilities extend from alternative splicing and transcript editing in the nucleus to mRNA stability, and translation into the cytoplasm. In this way, CELF family members have been connected to global alterations in cancer proliferation and invasion, leading to their identification as potential tumor suppressors or even oncogenes. Notably, genetic variants, alternative splicing, phosphorylation, acetylation, subcellular distribution, competition with other RBPs, and ultimately lncRNAs, miRNAs, and circRNAs all impact CELF regulation. Discoveries have emerged about the control of CELF functions, particularly via noncoding RNAs, and CELF proteins have been identified as competing, antagonizing, and regulating agents of noncoding RNA biogenesis. On the other hand, CELFs are an intriguing example through which to broaden our understanding of the RBP/noncoding RNA regulatory axis. Balancing these complex pathways in cancer is undeniably pivotal and deserves further research. This review outlines some mechanisms of CELF protein regulation and their functional consequences in cancer physiology.

miR-195-5p regulates cell proliferation, apoptosis, and invasion of thyroid cancer by targeting telomerase reverse transcriptase

In most human primary cancers, the expression, or telomerase activity, of telomerase reverse transcriptase (TERT) is detectable. However, the mechanism ofTERTactivity within oncogenesis of thyroid cancer remains largely unknown. In this study, we identified miR-195-5p as having involvement in cell proliferation, apoptosis, and invasion in human thyroid cancer. MTT was used to measure cell proliferation, Transwell chamber was used to measure invasion. Western blotting was used to detect the expressions of TERT, PCNA, and Ki67. Target gene prediction software predicted that TERT may be the target gene of miR-195-5p. Luciferase reporting system was used to identify the targeting relationship. A significant increase of in TERT expression was observed by immunohistochemistry compared with normal tissue, however, a decrease in miR-195-5p expression using qRT-PCRand western blot compared with normal cells. Functional analysis demonstrates that miR-195-5p negatively correlated withTERTand inhibitedTERTexpression through its interaction with theTERT3ʹ-untranslatedregion (3ʹ-UTR). Overexpression of miR-195-5p was shown to inhibit proliferation and invasion, and promote apoptosis of CAL-62 thyroid cancer cells. miR-195-5p-mediatedeffects were rescued by the overexpression ofTERT. Altogether, our data demonstrate that miR-195-5p regulates cell proliferation, apoptosis, and invasion in human thyroid cancer viaTERT, providing evidence of a new potential therapeutic target for further investigation.

Analysis of ceRNA networks and identification of potential drug targets for drug-resistant leukemia cell K562/ADR

Background

Drug resistance is the main obstacle in the treatment of leukemia. As a member of the competitive endogenous RNA (ceRNA) mechanism, underlying roles of lncRNA are rarely reported in drug-resistant leukemia cells.

Methods

The gene expression profiles of lncRNAs and mRNAs in doxorubicin-resistant K562/ADR and sensitive K562 cells were established by RNA sequencing (RNA-seq). Expression of differentially expressed lncRNAs (DElncRNAs) and DEmRNAs was validated by qRT-PCR. The potential biological functions of DElncRNAs targets were identified by GO and KEGG pathway enrichment analyses, and the lncRNA-miRNA-mRNA ceRNA network was further constructed. K562/ADR cells were transfected with CCDC26 and LINC01515 siRNAs to detect the mRNA levels of GLRX5 and DICER1, respectively. The cell survival rate after transfection was detected by CCK-8 assay.

Results

The ceRNA network was composed of 409 lncRNA-miRNA pairs and 306 miRNA-mRNA pairs based on 67 DElncRNAs, 58 DEmiRNAs and 192 DEmRNAs. Knockdown of CCDC26 and LINC01515 increased the sensitivity of K562/ADR cells to doxorubicin and significantly reduced the half-maximal inhibitory concentration (IC₅₀) of doxorubicin. Furthermore, knockdown of GLRX5 and DICER1 increased the sensitivity of K562/ADR cells to doxorubicin and significantly reduced the IC₅₀ of doxorubicin.

Conclusions

The ceRNA regulatory networks may play important roles in drug resistance of leukemia cells. CCDC26/miR-140-5p/GLRX5 and LINC01515/miR-425-5p/DICER1 may be potential targets for drug resistance in K562/ADR cells. This study provides a promising strategy to overcome drug resistance and deepens the understanding of the ceRNA regulatory mechanism related to drug resistance in CML cells.

Circular RNAs and Cardiovascular Regeneration

circular RNAs (circRNAs) are a type of non-coding RNAs that are widely present in eukaryotic cells. They have the characteristics of stable structure, high abundance, and cell or tissue specific expression. circRNAs are single-stranded RNAs that are covalently back spliced to form closed circular loops. They may participate in gene expression and regulation through a variety of action modes. circRNAs can encode proteins or function by acting as miRNA sponges for protein translation. Since 2016, a growing number of research studies have shown that circRNAs play important role in the pathogenesis of cardiovascular disease. With the construction of circRNA database, the differential expression of circRNAs in the heart tissue samples from different species and the gradual elucidation of its mode of action in disease may become an ideal diagnosis biomarker and an effective therapeutic target. What can be expected surely has a broader application prospect. In this review, we summarize recent publications on circRNA biogenesis, expression profiles, functions, and the most recent studies of circRNAs in the field of cardiovascular diseases with special emphasis on cardiac regeneration.