LINC00473/miR-374a-5p regulates esophageal squamous cell carcinoma via targeting SPIN1 to weaken the effect of radiotherapy

Upregulated miR-374a-5p drives psoriasis pathogenesis through WIF1 downregulation and Wnt5a/NF-κB activation

BACKGROUND

Psoriasis is a chronic, inflammatory skin disease. MicroRNAs (miRNAs) are an abundant class of non-coding RNA molecules. Recent studies have shown that multiple miRNAs are abnormally expressed in patients with psoriasis. The upregulation of miR-374a-5p has been associated with psoriasis severity. However, the specific role of miR-374a-5p in the pathogenesis of psoriasis remain unclear.

METHODS

qRT-PCR was employed to validate the expression of miR-374a-5p in psoriatic lesions and in a psoriasis-like cell model constructed using a mixture of M5 (IL-17A, IL-22, OSM, IL-1α, and TNF-α). HaCaT cells were transfected with miR-374a-5p mimic/inhibitor, and assays including EdU, CCK-8, and flow cytometry were conducted to evaluate the effect of miR-374a-5p on cell proliferation. The expression of inflammatory cytokines IL-1β, IL-6, IL-8, and TNF-α was verified by qRT-PCR. Bioinformatics analysis and dual-luciferase reporter gene assay were performed to detect the downstream target genes and upstream transcription factors of miR-374a-5p, followed by validation of their expression through qRT-PCR and Western blotting. A psoriasis-like mouse model was established using imiquimod cream topical application. The psoriasis area and severity index scoring, hematoxylin-eosin histology staining, and Ki67 immunohistochemistry were employed to validate the effect of miR-374a-5p on the psoriatic inflammation phenotype after intradermal injection of miR-374a-5p agomir/NC. Additionally, the expression of pathway-related molecules and inflammatory factors such as IL-1β, IL-17a, and TNF-α was verified by immunohistochemistry.

RESULTS

Upregulation of miR-374a-5p was observed in psoriatic lesions and the psoriasis-like cell model. In vitro experiments demonstrated that miR-374a-5p not only promoted the proliferation of HaCaT cells but also upregulated the expression of inflammatory cytokines, including IL-1β, IL-6, IL-8, and TNF-α. Furthermore, miR-374a-5p promoted skin inflammation and epidermal thickening in the Imiquimod-induced psoriasis-like mouse model. Mechanistic studies revealed that miR-374a-5p led to downregulation of WIF1, thereby activating the Wnt5a/NF-κB signaling pathway. The transcription factor p65 encoded by RELA, as a subunit of NF-κB, further upregulated the expression of miR-374a-5p upon activation. This positive feedback loop promoted keratinocyte proliferation and abnormal inflammation, thereby facilitating the development of psoriasis.

CONCLUSION

Our findings elucidate the role of miR-374a-5p upregulation in the pathogenesis of psoriasis through inhibition of WIF1 and activation of the Wnt5a/NF-κB pathway, providing new potential therapeutic targets for psoriasis.

Exosome-transported of circ_0081069 induces SPIN1 production by binding to miR-195-5p to inhibit radiosensitivity in esophageal squamous cell carcinoma

Circ_0081069 plays a key role in tumor growth; however, its effect on radiosensitivity in esophageal squamous cell carcinoma (ESCC) remains unknown. The study is performed to reveal the association of circ_0081069 expression and radiosensitivity in ESCC and the underlying mechanism. Circ_0081069, miR-195-5p, and spindlin 1 (SPIN1) RNA expression were detected by quantitative real-time polymerase chain reaction. Protein expression was checked by Western blot analysis or immunohistochemistry assay. Cell viability, proliferation, cell apoptosis, migration, and invasion were investigated by cell counting kit-8, 5-Ethynyl-29-deoxyuridine, flow cytometry analysis, scratch test, and transwell assays, respectively. The sensitivity of ESCC cells to radiation was investigated by cell colony formation assay. The interactions among circ_0081069, miR-195-5p, and SPIN1 were identified by dual-luciferase reporter assay and RNA Immunoprecipitation assay. Xenograft mouse model assay was performed to determine the effect of circ_0007841 on radiosensitivity in vivo. Circ_0081069 and SPIN1 expression were upregulated, whereas miR-195-5p was downregulated in ESCC tissues, ESCC cells, and radiation-stimulated ESCC cells. Circ_0081069 silencing inhibited ESCC cell proliferation, invasion, and migration but improved cell apoptosis. In addition, circ_0081069 knockdown enhanced ESCC cell radiosensitivity in vitro and in vivo. Circ_0081069 bound to miR-195-5p and regulated radiosensitivity by binding to miR-195-5p in ESCC cells. Moreover, SPIN1, a target of miR-195-5p, rescued miR-195-5p-mediated effects in ESCC cells. Circ_0081069 was secreted from ESCC cells by being packaged into exosomes. Further, circ_0081069-Exo inhibited radiosensitivity in ESCC cells. Exosome-mediated transfer of circ_0081069 induced SPIN1 production by binding to miR-195-5p, further inhibiting radiosensitivity in ESCC.

Mechanisms of radiotherapy resistance and radiosensitization strategies for esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is the sixth most common cause of cancer-related mortality worldwide, with more than half of them occurred in China. Radiotherapy (RT) has been widely used for treating ESCC. However, radiation-induced DNA damage response (DDR) can promote the release of cytokines and chemokines, and triggers inflammatory reactions and changes in the tumor microenvironment (TME), thereby inhibiting the immune function and causing the invasion and metastasis of ESCC. Radioresistance is the major cause of disease progression and mortality in cancer, and it is associated with heterogeneity. Therefore, a better understanding of the radioresistance mechanisms may generate more reversal strategies to improve the cure rates and survival periods of ESCC patients. We mainly summarized the possible mechanisms of radioresistance in order to reveal new targets for ESCC therapy. Then we summarized and compared the current strategies to reverse radioresistance.

Non-coding RNAs in radiotherapy resistance: Roles and therapeutic implications in gastrointestinal cancer

Radiotherapy has become an indispensable and conventional means for patients with advanced solid tumors including gastrointestinal cancer. However, innate or acquired radiotherapy resistance remains a significant challenge and greatly limits the therapeutic effect, which results in cancer relapse and poor prognosis. Therefore, it is an urgent need to identify novel biomarkers and therapeutic targets for clarify the biological characteristics and mechanism of radiotherapy resistance. Recently, lots of studies have revealed that non-coding RNAs (ncRNAs) are the potential indicators and regulators of radiotherapy resistance via the mediation of various targets/pathways in different cancers. These findings may serve as a potential therapeutic strategy to overcome radiotherapy resistance. In this review, we will shed light on the recent findings regarding the functions and regulatory mechanisms of ncRNAs following radiotherapy, and comprehensively discuss their potential as biomarkers and therapeutic targets in radiotherapy resistance of gastrointestinal cancer.

Hsa_circ_0007380 silencing restrains the growth and enhances radiosensitivity in esophagus cancer by miR-644a/Spindlin 1 axis

Circular RNAs are frequently dysregulated and show important regulatory function of tumorigenesis in cancers. Hsa_circ_0007380 was found to be elevated in human radioresistant esophageal cancer cells. Here, this study aimed to investigate the action and mechanism of hsa_circ_0007380 in esophageal cancer carcinogenesis and radiosensitivity. Quantitative real-time PCR and western blotting were performed to detect levels of genes and proteins. Functional experiments were conducted using MTT assay, EdU assay, clonogenic survival assay, flow cytometry and murine xenograft model assay, respectively. The binding between miR-644a and hsa_circ_0007380 or spindlin1 (SPIN1) was validated using dual-luciferase activity assay. Hsa_circ_0007380 was highly expressed in esophagus cancer tissues and cells, knockdown of hsa_circ_0007380 suppressed esophagus cancer cell proliferation, induced apoptosis and enhanced radiosensitivity in vitro, and the same effects were also confirmed in nude mice. Mechanistically, hsa_circ_0007380 sequestered miR-644a to release SPIN1 expression, implying the hsa_circ_0007380/miR-644a/SPIN1 competing endogenous RNA network esophagus cancer cells. miR-644a was decreased in esophagus cancer, re-expression of miR-644a restrained cell growth and conferred radiosensitivity in esophagus cancer, which were reversed by SPIN1 overexpression. Besides that, inhibition of miR-644a abolished the promoting action of hsa_circ_0007380 knockdown on esophagus cancer apoptosis and radiosensitivity. Hsa_circ_0007380 silencing impedes cell growth and reinforces radiosensitivity in esophagus cancer by miR-644a/SPIN1 axis, suggesting a promising therapeutic target for esophagus cancer combined treatment.

Circ_0001686 knockdown suppresses tumorigenesis and enhances radiosensitivity in esophagus cancer through regulating miR-876-5p/SPIN1 axis

BACKGROUND

Abnormal expression of circular RNAs (circRNAs) plays an important role in tumorigenesis and radiosensitivity of many cancers. Nevertheless, it is not clear whether circ_0001686 is associated with the development and radiosensitivity of esophagus cancer.

METHODS

Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression levels of circ_0001686, microRNA-876-5p (miR-876-5p) and spindlin 1 (SPIN1). Counting Kit-8 (CCK-8) assay, EdU assay, flow cytometry and transwell assay were applied to evaluate cell viability, cell proliferation, cell apoptosis and cell invasion capacities. Radiosensitivity was monitored by colony formation assay. The target relationship between miR-876-5p and circ_0001686 or SPIN1 was identified by dual-luciferase reporter assay. The protein level of SPIN1 was measured by western blot assay. Xenograft tumor models were used to analyze the influence of circ_0001686 on radiosensitivity and tumor growth in vivo.

RESULTS

The expression levels of circ_0001686 and SPIN1 were increased, while miR-876-5p was decreased in esophagus cancer tissues and cells. Interference of circ_0001686 constrained cell proliferation and invasion, but promoted cell apoptosis and radiosensitivity. Additionally, miR-876-5p was the target of circ_0001686 and miR-876-5p inhibition effectively ameliorated the impacts of circ_0001686 deficiency on tumorigenesis and radiosensitivity. Moreover, SPIN1 was a direct target of miR-876-5p and SPIN1 overexpression partially overturned the effects of miR-876-5p transfection on tumor progression and radiosensitivity. Importantly, circ_0001686 could sponge miR-876-5p to regulate SPIN1 expression. In addition, circ_0001686 silencing also constrained tumor growth and increased radiosensitivity in vivo.

CONCLUSION

Circ_0001686 contributed to the progression and radioresistance of esophagus cancer cells via regulating SPIN1 expression by targeting miR-876-5p, providing a new therapeutic target for improving the prognosis of esophagus cancer patients.

The clinical prognostic value of lncRNA LINC00473 in cancer patients: A meta-analysis

BACKGROUND

LINC00473 is a promising long non-coding RNA. There is increasing evidence that SNHG7 is abnormally expressed in various tumors and is associated with cancer prognosis. However, identification of the effect of long non-coding RNA LINC00473 in tumors remains necessary.

METHODS

Up to August 15, 2021, we searched electronic databases, including PubMed, Cochrane Library, EMBASE, Medline, and Web of Science. The results were evaluated by pooled odds ratios (ORs) and hazard ratios (HRs) with 95% confidence intervals (CIs).

RESULTS

There weres 13 included literature totaling cancer patients involved in this meta-analysis. The aggregated results revealed that high expression of LINC00473 was significantly associated with unfavorable overall survival (HR = 1.66, 95% CI: 1.48-1.86, P < .00001), disease-free survival (HR = 1.59, 95% CI: 1.09-2.32, P = .02) in a variety of cancers. Additionally, increased LINC00473 expression was also correlated with tumor node metastasis stage ((III/IV vs I/II) OR = 4.67, 95% CI = 3.11-7.02, P < .00001), differentiation ((poor/moderately vs well) OR = 3.25, 95% CI = 1.41-7.50, P = .006), tumor size ((larger vs smaller) OR = 2.49, 95% CI = 1.26-4.91, P = .03), and lymph node metastasis ((positive vs negative) OR = 3.10, 95% CI = 2.13-4.51, P = .008) in patients with cancers. Besides, the Gene Expression Profiling Interactive Analysis dataset evaluated that LINC00473 was upregulated in a variety of tumors and predicted worse prognosis.

CONCLUSION

Our results of this meta-analysis demonstrated that high LINC00473 expression may become a potential target for predicting prognosis of human cancers.

The roles and mechanisms of the lncRNA-miRNA axis in the progression of esophageal cancer: a narrative review

BACKGROUND AND OBJECTIVE

Esophageal cancer is one of the most common malignant digestive tract tumors. Despite various treatment methods, the prognosis of patients remains unsatisfactory, largely due to an insufficient understanding of the mechanisms involved in the pathogenesis and progression of esophageal cancer. More than 98% of the nucleotide sequences in the human genome do not encode proteins, and their transcription products are noncoding RNAs (ncRNAs), mainly long noncoding RNAs (lncRNAs) and microRNAs (miRNAs). Experiments have shown that lncRNAs and miRNAs play crucial roles in the occurrence and progression of various human malignancies. These ncRNAs influence the progression of esophageal cancer through an intricate regulatory network. We herein summarized the roles and mechanisms of the lncRNA-miRNA axis in esophageal cancer cell proliferation, apoptosis, epithelial-mesenchymal transition (EMT), invasion and metastasis, drug resistance, radiotherapy resistance, and angiogenesis. This review provides a rationale for anticancer therapy that targets the lncRNA-miRNA axis in esophageal cancer.

METHODS

Related articles published in the PubMed database between 05/30/2008 to 09/10/2022 were identified using the following terms: "lncRNA AND miRNA AND esophageal cancer", "lncRNA AND miRNA AND cell proliferation", "lncRNA AND miRNA AND apoptosis", "lncRNA AND miRNA AND EMT", "lncRNA AND miRNA AND invasion and metastasis", "lncRNA AND miRNA AND drug resistance", and "lncRNA AND miRNA AND radiotherapy resistance". Published articles written in English available to readers were considered.

KEY CONTENT AND FINDINGS

We summarized the roles of the lncRNA-miRNA axis in the progression of esophageal cancer, including cell proliferation, apoptosis, EMT, invasion and metastasis, drug resistance, radio resistance, and other progressions, and determined that the lncRNA-miRNA axis may serve as a potential clinical treatment target for esophageal cancer.

CONCLUSIONS

The lncRNA-miRNA axis is closely related to the progression of esophageal cancer and may act as a potential biological target for the clinical treatment of patients with esophageal cancer.

Revealing the role of miRNA-489 as a new onco-suppressor factor in different cancers based on pre-clinical and clinical evidence

Recently, microRNAs (miRNAs) have shown to be potential therapeutic, diagnostic and prognostic targets in disease therapy. These endogenous non-coding RNAs contribute to regulation of different cellular events that are necessary for maintaining physiological condition. Dysregulation of miRNAs is correlated with development of various pathological events such as neurological disorders, cardiovascular diseases, and cancer. miRNA-489 is a new emerging miRNA and studies are extensively investigating its role in pathological conditions. Herein, potential function of miRNA-489 as tumor-suppressor in various cancers is described. miRNA-489 is able to sensitize cancer cells into chemotherapy by disrupting molecular pathways involved in cancer growth such as PI3K/Akt, and induction of apoptosis. The PROX1 and SUZ12 as oncogenic pathways, are affected by miRNA-489 in suppressing metastasis of cancer cells. Wnt/β-catenin as an oncogenic factor ensuring growth and malignancy of tumors is inhibited via miRNA-489 function. For enhancing drug sensitivity of tumors, restoring miRNA-489 expression is a promising strategy. The lncRNAs can modulate miRNA-489 expression in tumors and studies about circRNA role in miRNA-489 modulation should be performed. The expression level of miRNA-489 is a diagnostic tool for tumor detection. Besides, down-regulation of miRNA-489 in tumors provides unfavorable prognosis.

Screening of Parkinson's Differential MicroRNA Based on GEO Database and Its Clinical Verification

Objective

This study is set out to explore the potential difference of miR in PD through GEO data and provide diagnostic indicators for clinical practice.

Methods

In this study, differential miR was screened through the Gene Expression Omnibus (GEO) database, 68 PD patients treated in our hospital from May 2017 to March 2018 were collected as the research group (RG), and 50 normal subjects who underwent physical examination in our hospital during the same period were collected as the control group (CG). Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression and diagnostic value of miR-374a-5p in serum of patients. The potential target genes of miR-374a-5p were predicted, and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis and Gene Ontology Consortium (GO) were carried out.

Results

GEO2R analysis revealed that 193 miRs are expressed differentially, of which 78 were highly expressed and 115 were poorly expressed. The miR-374a-5p expression in the serum of the RG was reduced markedly and had a diagnostic value. Targetscan and miRDB online websites were used to predict their target genes, with 415 common target genes. miR-374a-5p may participate in 27 functional pathways and 8 signal pathways.

Conclusion

miR-335-5p has low expression in PD and is expected to be a potential diagnostic indicator.

LINC00473 protects against cerebral ischemia reperfusion injury via sponging miR-15b-5p and miR-15a-5p to regulate SRPK1 expression

BACKGROUND

Cerebral ischemia is associated with a high burden of neurological disability. Recently, emerging evidence has demonstrated that long non-coding RNAs (lncRNAs) are crucial regulators in cerebral ischemia reperfusion (I/R) injury. Herein, we investigated the function and potential mechanism of long intergenic non-protein coding RNA 473 (LINC00473) in cerebral I/R injury.

METHODS

We established oxygen glucose deprivation/reperfusion (OGD/R) model in Neuro-2a (N2a) cells to mimic the cerebral I/R injury in vitro. RT-qPCR and Western blot assays were conducted to detect target gene expression. Functional assays measured the effects of LINC00473 on cell viability, apoptosis and reactive oxygen species (ROS) production. A series of mechanism assays were carried out to detect the potential mechanism of LINC00473 in cerebral I/R injury.

RESULTS

LINC00473 was significantly down-regulated in OGD/R-induced injury model. LINC00473 overexpression reversed the reduced cell viability as well as the enhanced apoptosis and ROS level induced by OGD/R. Moreover, LINC00473 functioned as a competing endogenous RNA (ceRNA) to sponge miR-15b-5p and miR-15a-5p and thereby regulated SRSF protein kinase 1 (SRPK1) expression.

CONCLUSIONS

Our findings confirmed the protective role of LINC00473 in cerebral I/R injury, which might provide a novel target for treating ischemic brain injury.

Histone code reader SPIN1 is a promising target of cancer therapy

SPIN1 is a histone methylation reader, which can epigenetically control multiple tumorigenesis-associated signaling pathways, including the Wnt, PI3K/AKT, and RET pathways. Considerable evidence has shown that SPIN1 is overexpressed in many cancers, which can promote cell proliferation, transformation, metastasis, and chemical or radiation resistance. With the growing understanding of the SPIN1 protein structure, some inhibitors have been developed to interfere with the recognition between SPIN1 and histone H3K4me3 and H3R8me2a methylation and block the oncogenic functions of SPIN1. Therefore, SPIN1 is a potential target of cancer therapy. However, the mechanism by which SPIN1-transformed cells overcome the significant mitotic spindle defects and the factors promoting SPIN1 overexpression in cancers remain unclear. In this review, we described the current understanding of the SPIN1 protein structure and its expression, functions, and regulatory mechanisms in carcinogenesis, and discussed the challenges faced in the mechanisms of SPIN1 overexpression and oncogenic functions, and the potential application of anti-SPIN1 treatment in human cancers.

miR-374a-5p inhibits non-small cell lung cancer cell proliferation and migration via targeting NCK1

Emerging studies have indicated that microRNAs (miRNAs/miRs) are involved in regulating non-small cell lung cancer (NSCLC)-associated processes. The present study aimed to evaluate the biological roles of miR-374a-5p in NSCLC. Using reverse transcription-quantitative PCR, the expression levels of miR-374a-5p were determined in NSCLC cells and a normal cell line. Functional experiments were performed to investigate the functions of miR-374a-5p in NSCLC. A luciferase activity reporter assay and rescue experiments were performed to validate NCK adaptor protein 1 (NCK1) as a functional target of miR-374a-5p. It was demonstrated that miR-374a-5p levels were decreased in NSCLC cell lines compared with those in a normal cell line. Furthermore, overexpression of miR-374a-5p inhibited NSCLC cell proliferation and migration in vitro. Of note, NCK1 overexpression reversed the effects of miR-375a-5p on NSCLC cell proliferation and migration. The present results confirmed the tumor suppressor role of miR-374a-5p via targeting NCK1 in NSCLC, indicating the importance of the miR-374a-5p/NCK1 axis in NSCLC.

LncRNA LINC00473 is involved in the progression of invasive pituitary adenoma by upregulating KMT5A via ceRNA-mediated miR-502-3p evasion

Long noncoding RNAs (lncRNAs) and their crosstalks with other RNAs have been revealed to be closely related to tumorigenesis and development, but their role in invasive pituitary adenoma (IPA) remains largely unclear. In our study, LINC00473 was identified as the most upregulated lncRNA in IPA by whole transcriptome RNA sequencing (RNA-Seq). Further, its related signaling pathway LINC00473/miR-502-3p/KMT5A was obtained by constructing a competing endogenous RNA (ceRNA) regulatory network. Their expression in IPA and non-invasive pituitary adenoma (NIPA) tissues was verified by qRT-PCR. Then the effects and mechanisms of LINC00473 and its ceRNA network on the proliferation of pituitary adenoma (PA) cells were confirmed by gene overexpression or silencing techniques combined with CCK-8 assay, EdU staining, flow cytometry assay, and double luciferase reporter gene assay in PA cell lines AtT-20 and GT1-1 in vitro and in a xenograft model in vivo. LINC00473 is overexpressed in IPA and can promote PA cells proliferation. Mechanistically, overexpression of LINC00473 restricts miR-502-3p through the ceRNA mechanism, upregulates KMT5A expression, and promotes the expression of cyclin D1 and CDK2, which is conducive to the cell cycle process, thereby promoting the proliferation of PA cells, involving IPA progression.

lncRNA LINC00473 promotes proliferation, migration, invasion and inhibition of apoptosis of non-small cell lung cancer cells by acting as a sponge of miR-497-5p

Lung cancer is the leading cause of cancer-associated death worldwide and exhibits a poor prognosis. The present study aimed to determine the effect of long non-coding (lnc)RNA-LINC00473 on the development of non-small cell lung cancer (NSCLC) cells by regulating the expression of microRNA (miR)-497-5p. Reverse transcription-quantitative PCR was conducted to detect the level of LINC00473 and miR-497-5p. An MTT assay, flow cytometry and Transwell tests were performed to evaluate the proliferation, apoptosis, migration and invasion of NSCLC cells. Western blotting was performed to detect the expression of apoptosis- and migration-related proteins. RNA immunoprecipitation and a luciferase reporter assay were performed to verify the regulatory relationship between lncRNA-LINC00473 and miR-497-5p. LINC00473 expression was upregulated in lung cancer tissues and NSCLC cells (A549 and H1299) when compared with adjacent tissues or human bronchial epithelial cell lines and the 5-year survival rate was lower in patients with high LINC00473 expression compared with in patients with low LINC00473 expression. A negative correlation between LINC00473 and miR-497-5p was observed in lung cancer tissues. Proliferation, migration and invasion as well as the related protein levels were increased in A549 and H1299 transfected with pcDNA3.1-LINC00473, while the opposite results were obtained in A549 and H1299 transfected with small interfering (si)-LINC00473. Notably, it was demonstrated that LINC00473 could bind directly with miR-497-5p and inhibit its expression. miR-497-5p inhibitors reversed the effect of si-LINC00473. Furthermore, the present study demonstrated that LINC00473 promoted the malignant behaviour of NSCLC cells via regulating the ERK/p38 and MAPK signalling pathways and the expression of miR-497-5p.

Driving integrative structural modeling with serial capture affinity purification

Determining the three-dimensional structures of protein complexes is critically important to guide biological research. Structural models of complexes can be built using powerful integrative approaches that combine emerging technologies in mass spectrometry, molecular modeling, and protein docking; however, preparing enriched biochemical samples suitable for analysis remains a major challenge. Here we describe serial capture affinity purification (SCAP), which can be used for the study of protein interactions in live cells and, when combined with cross-linking mass spectrometry, contribute distance restraints for integrative structural modeling. This broadly applicable technology can be used to study any protein complex in human tissue culture cells. We demonstrate SCAP capabilities on a poorly characterized epigenetic protein complex with roles in human cancer.

Streamlined characterization of protein complexes remains a challenge for the study of protein interaction networks. Here we describe serial capture affinity purification (SCAP), in which two separate proteins are tagged with either the HaloTag or the SNAP-tag, permitting a multistep affinity enrichment of specific protein complexes. The multifunctional capabilities of this protein-tagging system also permit in vivo validation of interactions using acceptor photobleaching Förster resonance energy transfer and fluorescence cross-correlation spectroscopy quantitative imaging. By coupling SCAP to cross-linking mass spectrometry, an integrative structural model of the complex of interest can be generated. We demonstrate this approach using the Spindlin1 and SPINDOC protein complex, culminating in a structural model with two SPINDOC molecules docked on one SPIN1 molecule. In this model, SPINDOC interacts with the SPIN1 interface previously shown to bind a lysine and arginine methylated sequence of histone H3. Our approach combines serial affinity purification, live cell imaging, and cross-linking mass spectrometry to build integrative structural models of protein complexes.

LINC00473: A novel oncogenic long noncoding RNA in human cancers

Long noncoding RNAs (lncRNAs) have been found to play essential roles in the occurrence and development of multiple human cancers. Accumulating evidence has shown that LINC00473, an oncogenic lncRNA, is upregulated in various human malignancies and related to poor clinical outcomes. Besides, LINC00473 overexpression can promote cell proliferation, migration, and invasion through multiple potential mechanisms, indicating that it may serve as a novel prognostic biomarker and therapeutic target for human cancers. Here, we reviewed the biological functions, molecular mechanisms, and clinical implications of LINC00473 in human cancers.

LINC00473 as an Immediate Early Gene under the Control of the EGR1 Transcription Factor

Immediate early genes play an essential role in cellular responses to different stimuli. Many of them are transcription factors that regulate the secondary response gene expression. Non-coding RNAs may also be involved in this regulatory cascade. In fact, they are emerging as key actors of gene expression regulation, and evidence suggests that their dysregulation may underly pathological states. We previously took a snapshot of both coding and long non-coding RNAs differentially expressed in neuronal cells after brain-derived neurotrophic factor stimulation. Among these, the transcription factor EGR1 (a well-known immediate early gene) and LINC00473 (a primate-specific long non-coding RNA) that has emerged as an interesting RNA candidate involved in neuronal function and in cancer. In this work, we demonstrated that LINC00473 gene expression kinetics resembled that of immediate early genes in SH-SY5Y and HEK293T cells under different cell stimulation conditions. Moreover, we showed that the expression of LINC00473 is under the control of the transcription factor EGR1, providing evidence for an interesting functional relationship in neuron function.

Knockdown of LINC00473 promotes radiosensitivity of non-small cell lung cancer cells via sponging miR-513a-3p

Non-small cell lung cancer (NSCLC) is the most common form of lung cancer. Radioresistance is a significant obstacle in NSCLC radiotherapy. Long non-coding RNA LINC00473 has been found to impact the radiotherapy in several malignant tumours. This study aimed to investigate the underlying role and mechanism of LINC00473 in regulating radiosensitivity of NSCLC cells. The levels of LINC00473 and miR-513a-3p were measured by quantitative Real-Time PCR. The relationship of LINC00473 with overall survival was tested by the Kaplan-Meier method. The effects of LINC00473 on cell viability and cell survival were assessed by cell counting kit-8 (CCK-8) and colony survival assay in NSCLC cells exposed to different doses of radiation. A luciferase reporter assay was used to investigate the correlation between LINC00473 and miR-513a-3p. The present study showed that the relative LINC00473 expression was upregulated and miR-513a-3p expression was downregulated in radioresistant NSCLC patients compared with radiosensitive patients. And upregulated LINC00473 expression was associated with poor prognosis of NSCLC patients after radiotherapy. Radiation led to an increase in LINC00473 expression in a dose- and time-dependent manner. The knockdown of LINC00473 markedly promoted radiosensitivity in NSCLC cells under different doses of radiation. LINC00473 was a sponge of miR-513a-3p and negatively regulated the miR-513a-3p expression. In conclusion, the inhibition of miR-513a-3p markedly reversed the promoted effect of LINC00473 knockdown on cell radiosensitivity. LINC00473 inhibition enhances radiosensitivity of NSCLC by sponging miR-513a-3p, providing a promising therapeutic target to increase the sensitivity of radiotherapy in NSCLC patients.

The long non-coding RNA LINC00473 contributes to cell proliferation via JAK-STAT3 signaling pathway by regulating miR-195-5p/SEPT2 axis in prostate cancer

Prostate cancer is a kind of male malignant tumor, which has brought tremendous health threat to men. Prostate cancer is difficult to be cured because of high incidence and metastasis rate. Thereby, it is of great urgency to elucidate the underlying molecular mechanism of prostate cancer for the treatment of this cancer. LINC00473 dysregulation has been observed in many cancers. However, the role of LINC00473 was unknown in prostate cancer. In the present study, we discovered that prostate cancer cells presented high expression of LINC00473, and LINC00473 inhibition limited cell proliferation and the expression of proteins in JAK-STAT3 signaling pathway. Additionally, LINC00473 acted as an up-stream factor for miR-195-5p to negatively modulate miR-195-5p expression. Moreover, SEPT2 interacted with miR-195-5p in prostate cancer and SEPT2 expression was positively modulated by LINC00473 and negatively regulated by miR-195-5p. Last, the inhibitory effect of LINC00473 knockdown on cell proliferation and expression of proteins of JAK-STAT3 signaling pathway was restored by SEPT2 overexpression. All in all, LINC00473 contributed to cell proliferation via JAK-STAT3 signaling pathway by regulating miR-195-5p/SEPT2 axis in prostate cancer, which provided a novel therapeutic tactic for prostate cancer patients.

Long Non-Coding RNAs as Strategic Molecules to Augment the Radiation Therapy in Esophageal Squamous Cell Carcinoma

Intrinsic resistance to ionizing radiation is the major impediment in the treatment and clinical management of esophageal squamous cell carcinoma (ESCC), leading to tumor relapse and poor prognosis. Although several biological and molecular mechanisms are responsible for resistance to radiotherapy in ESCC, the molecule(s) involved in predicting radiotherapy response and prognosis are still lacking, thus requiring a detailed understanding. Recent studies have demonstrated an imperative correlation amongst several long non-coding RNAs and their involvement in complex cellular networks like DNA damage and repair, cell cycle, apoptosis, proliferation, and epithelial-mesenchymal transition. Additionally, accumulating evidence has suggested abnormal expression of lncRNAs in malignant tumor cells before and after radiotherapy effects in tumor cells' sensitivity. Thus, lncRNAs indeed represent unique molecules that can influence tumor cell susceptibility for various clinical interventions. On this note, herein, we have summarized the current status of lncRNAs in augmenting resistance/sensitivity in ESCC against radiotherapy. In addition, we have also discussed various strategies to increase the radiosensitivity in ESCC cells under clinical settings.

E2F1-activated SPIN1 promotes tumor growth via a MDM2-p21-E2F1 feedback loop in gastric cancer

Gastric cancer (GC) is one of the most common cancers around the world. Searching for specific gene expression changes during the development of GC could help identify potential therapy targets. We previously showed that the histone code reader SPIN1 may act as an oncogene in breast cancer. At present, the biological function and regulation of SPIN1 in GC remain unclear. Here, we demonstrate that SPIN1 is upregulated in GC tissues, compared with nontumorous gastric tissues. Increased expression of SPIN1 is closely associated with poor prognosis for patients with GC. Increased SPIN1 expression enhances GC cell proliferation, migration, and invasion and promotes cell cycle progression. Mechanically, SPIN1 sustains GC cell proliferation via activation of the MDM2-p21-E2F1 signaling pathway by binding to H3K4me3 of the MDM2 promoter region. Interestingly, E2F1 could directly bind to the SPIN1 promoter and activate its transcription, thus forming a positive feedback loop. Our data suggest that SPIN1 plays an important role in the development of GC and could be used as a promising prognostic biomarker and therapeutic target for GC.

Chlorotoxin fusion protein regulates miR-374a and TNFAIP8 expression and inhibits glioma cell proliferation and promotes apoptosis

Glioblastoma multiforme is the most common primary central nervous system malignancy, accounting for half of all intracranial primary tumors. In this study we constructed a multifunctional chlorotoxin fusion protein E-CHP that combines enhanced green fluorescent protein (E), glioma-targeting peptide chlorotoxin (C), destabilizing lipid membrane peptide riHA2 (H), and C-terminal and mouse double minute domains of p53 (P). E-CHP was expressed in Escherichia coli and purified by His affinity chromatography. Fluorescence microscopy observation showed that E-CHP could effectively target glioma cells; real-time quantitative PCR revealed that E-CHP increased miR-374a expression; and the dual luciferase reporter assay showed that tumor necrosis factor alpha-induced protein (TNFAIP)8 is a direct target of miR-374a. E-CHP and miR-374a inhibited the proliferation and migration of glioma cells, and Western blot analysis indicated that they suppressed TNFAIP8 expression in glioma cells and promoted the expression of caspase-3 and -8. Finally, E-CHP and miR-374a stimulated the apoptosis of glioma cells, as determined by flow cytometry analysis. These results suggest that miR-374a is a new candidate target for glioma therapy, whereas E-CHP fusion protein has the potential to be developed as a multifunctional carrier for targeted drug delivery and therapy.

Comprehensive analysis of competitive endogenous RNAs network reveals potential prognostic lncRNAs in gastric cancer

Long non-coding RNAs (lncRNAs) are key regulators of a range of human diseases, including various cancers, with multiple previous studies having explored lncRNA dysregulation in the context of gastric cancer (GC). The present study sought to expand upon these previous results by downloading lncRNA, mRNA, and microRNA (miRNA) expression profiles derived from 180 GC tissues and 24 normal control tissues within the Cancer Genome Atlas (TCGA) database. These datasets were then interrogated to identify GC-related differentially expressed (DE) RNAs (|fold change| ≥ 2, FDR< 0.01), leading to the identification of 1946 DE lncRNAs, 123 DE miRNAs, and 3159 DE mRNAs. These results were then used to generate a putative GC-related competitive endogenous RNA (ceRNA) network composed of 131 lncRNAs, 9 miRNAs, and 78 mRNAs. Subsequent survival analyses based upon this network revealed 17 of these lncRNAs to be significantly associated with GC patient survival (P < 0.05). Further multivariable Cox regression and lasso analyses allowed for the construction of an 8-lncRNA risk score that was able to effectively predict GC patient survival with good discriminative ability. The Kaplan-Meier Plotter database further confirmed that network hub genes that were related to these 8 lncRNAs were associated with GC patient prognosis (P < 0.05). As the ceRNA network in the present study was constructed with a focus on both disease stage and differential gene expression, it represents a key resource that will offer valuable insights into the mechanistic roles of ceRNA pathways in GC development and progression.

LINC00473 contributes to the radioresistance of esophageal squamous cell carcinoma by regulating microRNA‑497‑5p and cell division cycle 25A

Long non-coding RNA (lncRNA) LINC00473 plays a carcinogenic role in a variety of different tumor types. Nevertheless, the mechanisms through which LINC00473 regulates the radiosensitivity of esophageal squamous cell carcinoma (ESCC) cells remains elusive. In the present study, reverse transcription-quantitative PCR was used to quantify the expression of LINC00473, microRNA (miRNA/miR)-497-5p and cell division cycle 25A (CDC25A) in ESCC tissues. The association between LINC00473 expression and the clinicopathological characteristics of patients with ESCC was also assessed. Furthermore, Cell Counting kit-8 and colony formation assays were carried out to monitor the proliferation of ESCC cells exposed to X-ray radiation. A dual-luciferase reporter assay was also conducted to analyze the interaction between LINC00473 and miR-497-5p, as well as the interaction between CDC25A and miR-497-5p. The findings of the present study demonstrated that in ESCC tissues and cells, the expression levels of LINC00473 and CDC25A were significantly upregulated, while the expression of miR-497-5p was downregulated. The high expression level of LINC00473 was associated with a higher T stage, lymph node metastasis stage and a lower tumor differentiation grade in patients with ESCC. Following irradiation, transfection with miR-497-5p mimics reduced the promoting effect of LINC00473 overexpression on ESCC cell proliferation, and partially impeded the resistance of ESCC cells to X-ray radiation induced by LINC00473 overexpression. Moreover, transfection with miR-497-5p inhibitors partially alleviated the inhibitory effects of LINC00473 knockdown on cellular proliferation, and partly reversed the sensitivity of cells to X-ray irradiation induced by LINC00473 knockdown. Furthermore, it was confirmed that miR-497-5p was able to bind LINC00473 and the 3′-untranslated region of CDC25A. On the whole, the findings of the present study demonstrate that LINC00473 reduces the radiosensitivity of ESCC cells by modulating the miR-497-5p/CDC25A axis.

Knockdown of LINC00473 Enhances Radiosensitivity in Hepatocellular Carcinoma via Regulating the miR-345-5p/FOXP1 Axis

Background

Hepatocellular carcinoma (HCC) is the most common form of liver cancer. Radioresistance is a significant obstacle in HCC therapy. Long non-coding RNA 473 (LINC00473) has been found to impair the effect of radiotherapy. This study aimed to explore the function and molecular basis of LINC00473 in the radiosensitivity of HCC cells.

Methods

The levels of LINC00473, miR-345-5p and Forkhead Box P1 (FOXP1) were determined by quantitative real-time polymerase chain reaction. Cell viability was assessed by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay. Survival fraction was calculated by colony survival assay after exposure to different doses of radiation. Cell apoptosis was evaluated by flow cytometry. The interaction among LINC00473, miR-345-5p and FOXP1 was confirmed by dual-luciferase reporter assay. The protein level of FOXP1 was detected by Western blot assay.

Results

LINC00473 and FOXP1 were up-regulated, while miR-345-5p was down-regulated in HCC tissues and cells. Radiation elevated LINC00473 expression in a dose- and time-dependent manner. Depletion of LINC00473 inhibited proliferation and heightened radiosensitivity and apoptosis in HCC cells. In addition, LINC00473 was a sponge of miR-345-5p. Also, miR-345-5p overexpression sensitized HCC cells to radiation. Moreover, miR-345-5p directly targeted FOXP1. MiR-345-5p inhibition or FOXP1 up-regulation reversed the enhanced radiosensitivity caused by LINC00473 knockdown.

Conclusion

LINC00473 contributed to radioresistance in HCC via modulating the miR-345-5p/FOXP1 axis, which might provide a promising diagnostic marker for HCC radiotherapy.

Emerging Role of Non-Coding RNAs in Esophageal Squamous Cell Carcinoma

Esophageal squamous cell carcinoma (ESCC) is a highly prevalent tumor and is associated with ethnicity, genetics, and dietary intake. Non-coding RNAs (ncRNAs), specifically microRNAs (miRNAs), long ncRNAs (lncRNAs), and circular RNAs (circRNAs) have been reported as functional regulatory molecules involved in the development of many human cancers, including ESCC. Recently, several ncRNAs have been detected as oncogenes or tumor suppressors in ESCC progression. These ncRNAs influence the expression of specific genes or their associated signaling pathways. Moreover, interactions of ncRNAs are evident in ESCC, as miRNAs regulate the expression of lncRNAs, and further, lncRNAs and circRNAs function as miRNA sponges to compete with the endogenous RNAs. Here, we discuss and summarize the findings of recent investigations into the role of ncRNAs (miRNAs, lncRNAs, and circRNAs) in the development and progression of ESCC and how their interactions regulate ESCC development.

LINC00473/miR-497-5p Regulates Esophageal Squamous Cell Carcinoma Progression Through Targeting PRKAA1

Background: Esophageal squamous cell carcinoma (ESCC) is one of the esophageal cancers known as an aggressive malignant tumor. Long noncoding RNAs (lncRNAs) can be involved in the progression and development of cancers. lncRNA LINC00473 (LINC00473) was reported to exert an oncogenic influence on diverse cancers. However, neither the biological function nor the underlying mechanism of LINC00473 has been explored in ESCC. Aim of the Study: The aim of investigation is to explore the role of LINC00473 in ESCC. Methods: The expression of LINC00473, miR-497-5p, and protein kinase AMP-activated alpha 1 catalytic subunit (PRKAA1) was detected by reverse-transcription quantitative polymerase chain reaction assay. Cell counting kit-8 and 5-ethynyl-2'-deoxyuridine assays were carried out to measure cell proliferation. Cell migration was tested by transwell assay. Western blot assay was performed to examine the protein expression of PRKAA1, E-cadherin, N-cadherin, and Vimentin. The binding capacity between miR-497-5p and LINC00473 (or PRKAA1) was, respectively, studied by luciferase reporter and RNA immunoprecipitation assays. Pearson correlation analysis was adopted to analyze the correlation between miR-497-5p (or LINC00473) and PRKAA1. Results: LINC00473 presented much higher expression and LINC00473 suppression restrained the proliferation, migration, and epithelial-mesenchymal transition (EMT) process in ESCC cells. MiR-497-5p presented lower expression, binding with and negatively regulated by LINC00473 in ESCC. PRKAA1 was confirmed as a downstream target gene for miR-497-5p. PRKAA1 could combine with miR-497-5p, and LINC00473 knockdown or miR-497-5p overexpression downregulated the mRNA and protein expression of PRKAA1. At last, the inhibitory effects of LINC00473 knockdown on proliferation, migration, and EMT process were reversed by PRKAA1 overexpression in vitro and in vivo. Conclusions: LINC00473 regulates ESCC progression through miR-497-5p/PRKAA1 axis, which provides a new therapeutic strategy for ESCC patients.