Circ-LDLRAD3 Enhances Cell Growth, Migration, and Invasion and Inhibits Apoptosis by Regulating MiR-224-5p/NRP2 Axis in Gastric Cancer

Silencing circLDLRAD3 Inhibits Lung Cancer Progression by Regulating the miR-497-5p/PFKP Axis

PURPOSE

Lung cancer is one of the leading causes of death worldwide. Recent studies have shown that circular RNAs are dysregulated in a variety of cancers, but the mechanism in lung cancer is still indistinct. In our work, we explored the action mechanism of circLDLRAD3 in lung cancer.

METHODS

The abundance of circLDLRAD3, microRNA-497-5p (miR-497-5p) and platelet-type PFK (PFKP) was measured by real-time quantitative polymerase chain reaction (RT-qPCR) in lung cancer. Meanwhile, the level of PFKP was quantified by western blot. Cell counting kit-8 (CCK-8), 5-Ethynyl-2'-deoxyuridine (EdU) assay, transwell assay, wound healing assay, flow cytometry, western blot, immunohistochemical (IHC) assay and glycolysis metabolism analysis were performed for functional analyses. Furthermore, the interplay between miR-497-5p and circLDLRAD3 or FKPF was detected by the dual-luciferase reporter and RNA Immunoprecipitation (RIP) assays. Eventually, the in vivo experiments were applied to measure the role of circLDLRAD3.

RESULT

The levels of circLDLRAD3 and PFKP were increased. Silencing circLDLRAD3 inhibited cell viability, proliferation, migration, invasion and glycolysis metabolism and promoted cell apoptosis in lung cancer cells. In mechanism, circLDLRAD3 regulated PFKP level as a miR-497-5p sponge. MiR-497-5p suppressed the progression of lung cancer by inhibiting PFKP. In addition, circLDLRAD3 knockdown also inhibited tumor growth in vivo.

CONCLUSION

CircLDLRAD3 promoted the development of lung cancer through increasing PFKP expression by regulating miR-497-5p, which also provided a potential targeted therapy for lung cancer treatment.

miR-224-5p Suppresses Non-Small Cell Lung Cancer via IL6ST-Mediated Regulation of the JAK2/STAT3 Pathway

BACKGROUND

Our study aimed to explore the specific functions and potential mechanisms of miR-224-5p in non-small cell lung cancer (NSCLC).

METHODS

We first analyzed the expression of miR-224-5p in NSCLC patients and cell lines through the GEO database and qRT-PCR analysis. Then, we used MTT assays, wound healing assays, Transwell assays, and western blotting to evaluate the effects of miR-224-5p on NSCLC cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT). Furthermore, we used a xenograft tumor model to evaluate the effect of miR-224-5p on NSCLC tumor growth. Potential binding targets of miR-224-5p were further identified through the target prediction databases, and the relationships between miR-224-5p, its targets, and downstream signaling pathways were further verified using luciferase reporter gene assays and western blotting.

RESULTS

The GEO database and qRT-PCR analysis indicated that miR-224-5p was significantly downregulated in NSCLC patients and cell lines. Functional assays indicated that inhibiting miR-224-5p could enhance the proliferation, migration, invasion, and EMT of NSCLC cells, as well as accelerate tumor growth. In contrast, overexpression of miR-224-5p inhibited these processes. We identified IL6ST (interleukin 6 signal transducer) as a binding target of miR-224-5p. We observed that miR-224-5p could bind to and inhibit IL6ST expression and JAK2/STAT3 signaling pathway, and the inhibition of NSCLC tumor growth and JAK2/STAT3 pathway by miR-224-5p could be reversed by IL6ST overexpression.

CONCLUSION

Our study demonstrated that miR-224-5p inhibited NSCLC by targeting IL6ST, thereby downregulating the JAK2/STAT3 signaling pathway.

circ_0006988 promotes gastric cancer cell proliferation, migration and invasion through miRNA-92a-2-5p/TFAP4 axis

Aim: To explore precise function and underlying mechanism of circ_0006988 in gastric cancer (GC).Materials & methods: GC tissues were collected clinically, and GC cells were purchased from the company. Quantitative real-time polymerase chain reaction and western blot were used to detect mRNA and protein expression. Functional analysis was performed through CCK-8, Transwell and scratch experiment. Binding relationship was validated through dual luciferase reporter and RNA immunoprecipitation assays. HGC-27 cells were subcutaneously injected into mice to construct a xenograft tumor model.Results: In GC tissues and cells, circ_0006988 overexpressed, promoting proliferation, migration and invasion. MiRNA-92a-2-5p downregulation or TFAP4 overexpression weakened effects of circ_0006988 silencing on GC progression.Conclusion: circ_0006988 facilitates GC development through miRNA-92a-2-5p/TFAP4 axis.

Neuropilins as potential biomarkers in hepatocellular carcinoma: a systematic review of basic and clinical implications

Hepatocellular carcinoma (HCC) is one of the most common and deadly cancers worldwide and is characterized by complex molecular carcinogenesis. Neuropilins (NRPs) NRP1 and NRP2 are the receptors of multiple proteins involved in key signaling pathways associated with tumor progression. We aimed to systematically review all the available findings on their role in HCC. We searched the Scopus, Web of Science (WOS), PubMed, Cochrane and Embase databases for articles evaluating NRPs in preclinical or clinical HCC models. This study was registered in PROSPERO (CRD42022349774) and include 49 studies. Multiple cellular and molecular processes have been associated with one or both NRPs, indicating that they are potential diagnostic and prognostic biomarkers in HCC patients. Mainly NRP1 has been shown to promote tumor cell survival and progression by modulating several signaling pathways. NRPs mainly regulate angiogenesis, invasion and migration and have shown to induce invasion and metastasis. They also regulate the immune response and tumor microenvironment, showing a crucial interplay with the hypoxia response and microRNAs in HCC. Altogether, NRP1 and NRP2 are potential biomarkers and therapeutic targets, providing novel insight into the clinical landscape of HCC patients.

The Tumorigenic Role of Circular RNA-MicroRNA Axis in Cancer

Circular RNAs (circRNAs) are a class of endogenous RNAs that control gene expression at the transcriptional and post-transcriptional levels. Recent studies have increasingly demonstrated that circRNAs act as novel diagnostic biomarkers and promising therapeutic targets for numerous cancer types by interacting with other non-coding RNAs such as microRNAs (miRNAs). The miRNAs are presented as crucial risk factors and regulatory elements in cancer by regulating the expression of their target genes. Some miRNAs are derived from transposable elements (MDTEs) that can transfer their location to another region of the genome. Genetic interactions between miRNAs and circular RNAs can form complex regulatory networks with various carcinogenic processes that play critical roles in tumorigenesis and cancer progression. This review focuses on the biological regulation of the correlative axis among circular RNAs, miRNAs, and their target genes in various cancer types and suggests the biological importance of MDTEs interacting with oncogenic or tumor-suppressive circRNAs in tumor progression.

Integration of TE Induces Cancer Specific Alternative Splicing Events

Alternative splicing of messenger RNA (mRNA) precursors contributes to genetic diversity by generating structurally and functionally distinct transcripts. In a disease state, alternative splicing promotes incidence and development of several cancer types through regulation of cancer-related biological processes. Transposable elements (TEs), having the genetic ability to jump to other regions of the genome, can bring about alternative splicing events in cancer. TEs can integrate into the genome, mostly in the intronic regions, and induce cancer-specific alternative splicing by adjusting various mechanisms, such as exonization, providing splicing donor/acceptor sites, alternative regulatory sequences or stop codons, and driving exon disruption or epigenetic regulation. Moreover, TEs can produce microRNAs (miRNAs) that control the proportion of transcripts by repressing translation or stimulating the degradation of transcripts at the post-transcriptional level. Notably, TE insertion creates a cancer-friendly environment by controlling the overall process of gene expression before and after transcription in cancer cells. This review emphasizes the correlative interaction between alternative splicing by TE integration and cancer-associated biological processes, suggesting a macroscopic mechanism controlling alternative splicing by TE insertion in cancer.

Immune-related gene signature associates with immune landscape and predicts prognosis accurately in patients with Wilms tumour

Wilms tumour (WT) is the most common kidney malignancy in children. Chemoresistance is the leading cause of tumour recurrence and poses a substantial therapeutic challenge. Increasing evidence has underscored the role of the tumour immune microenvironment (TIM) in cancers and the potential for immunotherapy to improve prognosis. There remain no reliable molecular markers for reflecting the immune landscape and predicting patient survival in WT. Here, we examine differences in gene expression by high-throughput RNA sequencing, focused on differentially expressed immune-related genes (IRGs) based on the ImmPort database. Via univariate Cox regression analysis and Lasso-penalized Cox regression analysis, IRGs were screened out to establish an immune signature. Kaplan-Meier curves, time-related ROC analysis, univariate and multivariate Cox regression studies, and nomograms were used to evaluate the accuracy and prognostic significance of this signature. Furthermore, we found that the immune signature could reflect the immune status and the immune cell infiltration character played in the tumour microenvironment (TME) and showed significant association with immune checkpoint molecules, suggesting that the poor outcome may be partially explained by its immunosuppressive TME. Remarkably, TIDE, a computational method to model tumour immune evasion mechanisms, showed that this signature holds great potential for predicting immunotherapy responses in the TARGET-wt cohort. To decipher the underlying mechanism, GSEA was applied to explore enriched pathways and biological processes associated with immunophenotyping and Connectivity map (CMap) along with DeSigN analysis for drug exploration. Finally, four candidate immune genes were selected, and their expression levels in WT cell lines were monitored via qRT-PCR. Meanwhile, we validated the function of a critical gene, NRP2. Taken together, we established a novel immune signature that may serve as an effective prognostic signature and predictive biomarker for immunotherapy response in WT patients. This study may give light on therapeutic strategies for WT patients from an immunological viewpoint.

Role of Neuropilin-2-mediated signaling axis in cancer progression and therapy resistance

Neuropilins (NRPs) are transmembrane proteins involved in vascular and nervous system development by regulating angiogenesis and axon guidance cues. Several published reports have established their role in tumorigenesis. NRPs are detectable in tumor cells of several cancer types and participate in cancer progression. NRP2 is also expressed in endothelial and immune cells in the tumor microenvironment and promotes functions such as lymphangiogenesis and immune suppression important for cancer progression. In this review, we have taken a comprehensive approach to discussing various aspects of NRP2-signaling in cancer, including its regulation, functional significance in cancer progression, and how we could utilize our current knowledge to advance the studies and target NRP2 to develop effective cancer therapies.

circRNA LDLRAD3 Enhances the Malignant Behaviors of NSCLC Cells via the miR-20a-5p-SLC7A5 Axis Activating the mTORC1 Signaling Pathway

Circular RNA LDLRAD3 behaved as an oncogene in several malignancies, but its effects in NSCLC and the involvement of downstream molecules and activation of signaling pathways had not been fully reported. We planned to explore how LDLRAD3 facilitated the malignancy of NSCLC. QRT-PCR was performed to evaluate the expression levels of LDLRAD3, miR-20a-5p, and SLC7A5 in NSCLC tissues and cells. si-LDLRAD3 was transfected to A549 and H1299 cells to knock down intrinsic LDLRAD3 to determine its oncogenic roles. CCK-8 assay and transwell assay were executed to assess cell proliferative, migrative, and invasive abilities. Dual-luciferase reporter (DLR) assay was manipulated to verify the ENCORI-predicted relationships between LDLRAD3 and miR-20a-5p and between miR-20a-5p and SLC7A5. Western blot, immunofluorescent assay, and immunohistochemistry were applied to explore the expression levels of SLC7A5, and the levels of mTORC1 pathway-related proteins were evaluated using western blot. Rescue experiments were conducted by transfecting si-LDLRAD3, miR-20a-5p inhibitor, and si-SLC7A5 to explore the influence of the LDLRAD3-miR-20a-5p-SLC7A5 axis on the malignant behaviors of NSCLC cells. The expression levels of LDLRAD3 and SLC7A5 were boosted, whereas miR-20a-5p was impeded in NSCLC tissues and cell lines. Knockdown of LDLRAD3 weakened the proliferation, migration, and invasion of A549 and H1299 cells. LDLRAD3 was verified to sponge miR-20a-5p and miR-20a-5p targeted SLC7A5. LDLRAD3 activated the mTORC1 singling pathway via the miR-20a-5p-SLC7A5 axis to strengthen the malignant properties of A549 and H1299 cells. We concluded that LDLRAD3 exerted oncogenic effects via the miR-20a-5p-SLC7A5 axis to activate the mTORC1 signaling pathway in NSCLC. Our findings enlightened that LDLRAD3 could become a potential therapeutic target in the treatment and management of NSCLC.

A Novel Cancer Stemness-Related Signature for Predicting Prognosis in Patients with Colon Adenocarcinoma

Objective

To explore the cancer stemness features and develop a novel cancer stemness-related prognostic signature for colon adenocarcinoma (COAD).

Methods

We downloaded the mRNA expression data and clinical data of COAD from TCGA database and GEO database. Stemness index, mRNAsi, was utilized to investigate cancer stemness features. Weighted gene coexpression network analysis (WGCNA) was used to identify cancer stemness-related genes. Univariate and multivariate Cox regression analyses were applied to construct a prognostic risk cancer stemness-related signature. We then performed internal and external validation. The relationship between cancer stemness and COAD immune microenvironment was investigated.

Results

COAD patients with higher mRNAsi score or EREG-mRNAsi score have significant longer overall survival (OS). We identified 483 differently expressed genes (DEGs) between the high and low mRNAsi score groups. We developed a cancer stemness-related signature using fifteen genes (including RAB31, COL6A3, COL5A2, CCDC80, ADAM12, VGLL3, ECM2, POSTN, DPYSL3, PCDH7, CRISPLD2, COLEC12, NRP2, ISLR, and CCDC8) for prognosis prediction of COAD. Low-risk score was associated with significantly preferable OS in comparison with high-risk score, and the area under the ROC curve (AUC) for OS prediction was 0.705. The prognostic signature was an independent predictor for OS of COAD. Macrophages, mast cells, and T helper cells were the vital infiltration immune cells, and APC costimulation and type II IFN response were the vital immune pathways in COAD.

Conclusions

We developed and validated a novel cancer stemness-related prognostic signature for COAD, which would contribute to understanding of molecular mechanism in COAD.

Circ_0006988 promotes the proliferation, metastasis and angiogenesis of non-small cell lung cancer cells by modulating miR-491-5p/MAP3K3 axis

Circular RNAs (circRNAs) are related to the progression of non-small cell lung cancer (NSCLC). However, the roles and mechanism of circ_0006988 are largely unknown. The levels of circ_0006988, Low-Density Lipoprotein Receptor Class A Domain Containing 3 (LDLRAD3), microRNA-491-5p (miR-491-5p), Mitogen-Activated Protein Kinase Kinase Kinase 3 (MAP3K3) were measured using quantitative real-time polymerase-chain reaction (qRT-PCR) and western blot assay. The characteristic of circ_0006988 was analyzed by RNase R assay and Actinomycin D assay. Functional analyses were processed by Cell Counting Kit-8 (CCK-8) assay, 5-ethynyl-2'-deoxyuridine (EdU) assay, colony formation assay, flow cytometry analysis, transwell assay, wound-healing assay and tube formation assay. The interactions between circ_0006988 and miR-491-5p as well as miR-491-5p and MAP3K3 were analyzed by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. Murine xenograft model assay was processed to verify the function of circ_0006988 in vivo. Immunohistochemistry (IHC) assay was conducted to examine the level of Ki67. Circ_0006988 abundance was increased in NSCLC tissues and cells. Circ_0006988 silencing restrained NSCLC cell proliferation, migration, invasion and angiogenesis, and induced apoptosis. Circ_0006988 sponged miR-491-5p, which directly targeted MAP3K3. MiR-491-5p overexpression repressed NSCLC cell malignant behaviors. MiR-491-5p downregulation or MAP3K3 overexpression reversed the effect of circ_0006988 silencing on NSCLC cell progression. In addition, circ_0006988 knockdown reduced xenograft tumor growth. ssCirc_0006988 contributed to the development of NSCLC by miR-491-5p/MAP3K3 axis.

CircCSNK1G1 Contributes to the Tumorigenesis of Gastric Cancer by Sponging miR-758 and Regulating ZNF217 Expression

Background

Increasing evidence indicates that circular RNAs (circRNAs) act as vital regulators in various cancers. Nevertheless, the effect of circCSNK1G1 on gastric cancer (GC) is still unknown.

Methods

The mRNA levels of circCSNK1G1, miR-758, and ZNF217 were measured by RT-qPCR. The protein levels of ZNF217 were evaluated by Western blotting. Cell migration, invasion, proliferation, and apoptosis were detected by Transwell, CCK-8, and flow cytometry assays. The association between miR-758 and circCSNK1G1/ZNF217 was confirmed by RIP and luciferase reporter assays. Xenograft assay was employed for in vivo experiment.

Results

In the current study, it was demonstrated that the expression levels of circCSNK1G1 and ZNF217 were upregulated in GC tissues and cells, while the level of miR-758 was declined. Furthermore, functional assays indicated that circCSNK1G1 depletion suppressed GC progression in vitro and in vivo. In addition, circCSNK1G1 directly interacted with miR-758, and the supplementation of miR-758 suppressed the development of GC, which was abolished following pcDNA3.1-circCSNK1G1 transfection. Then, we explored the downstream mechanism of miR-758 and found that miR-758 could target the 3'UTR of ZNF217 mRNA. The overexpression of miR-758 neutralized the ZNF217-mediated effects on facilitating the progression of GC. Finally, we revealed that circCSNK1G1 could upregulate ZNF217 expression by sponging miR-758 in GC cells.

Conclusion

Our study revealed that circCSNK1G1 accelerated GC progression via the miR-758/ZNF217 axis, suggesting that circCSNK1G1 might be a potential biomarker for GC diagnosis and treatment.