The E2F3/miR-125a/DKK3 regulatory axis promotes the development and progression of gastric cancer

Role of ADP ribosylation factor guanylate kinase 1 in the malignant biological behavior of gastric cancer

Aim

This study aims to investigate the influence of ASAP1 (ADP ribosylation factor guanylate kinase 1) on the malignant behavior of gastric cancer (GC) cells and to elucidate the potential molecular mechanisms involved in cancer development and progression.

Methods

We assessed the impact of ASAP1 overexpression and knockdown on GC cell malignancy using CCK8, colony formation, flow cytometry (Annexin V/propidium iodide), Transwell migration, invasion, and scratch assays. Western blot analysis was used to assess the effects of ASAP1 on angiogenesis, matrix metalloproteinases (MMPs), apoptotic proteins, epithelial-mesenchymal transition (EMT)-related proteins, as well as AKT and p-AKT. The influence of ASAP1 knockdown was also evaluated in nude mice bearing BGC823 cell-derived tumors.

Results

Our findings revealed that ASAP1 was significantly overexpressed in GC cells, enhancing their proliferation, invasion, and migration, while reducing apoptosis. Conversely, ASAP1 knockdown reversed these effects, markedly increasing the expression of cleaved-caspase 3 (Casp3), PARP, and the epithelial marker E-cadherin, and significantly decreasing MMP2, MMP9, VEGFA, and mesenchymal markers such as N-cadherin and vimentin. Additionally, it reduced AKT, and p-AKT levels (P < 0.01). Tumor growth in nude mice was suppressed following ASAP1 knockdown.

Conclusion

The overexpression of ASAP1 significantly promotes malignant behaviors in GC cells, whereas its knockdown diminishes these effects. This modulation is potentially through the downregulation of VEGFA, leading to reduced angiogenesis, Cleaved-Casp3 and Cleaved-PARP overexpression, and a decrease in MMPs, EMT, AKT, and p-AKT activity.

Tubular biomarkers in proteinuric kidney disease: histology correlation and kidney prognosis of tubular biomarkers

Background

Proteinuria is not only a biomarker of chronic kidney disease (CKD) but also a driver of CKD progression. The aim of this study was to evaluate serum and urinary tubular biomarkers in patients with biopsied proteinuric kidney disease and to correlate them with histology and kidney outcomes.

Methods

A single-center retrospective study was conducted on a cohort of 156 patients from January 2016 to December 2021. The following urinary and serum biomarkers were analyzed on the day of kidney biopsy: beta 2 microglobulin (β2-mcg), alpha 1 microglobulin (α1-mcg), neutrophil gelatinase-associated lipocalin (NGAL), urinary kidney injury molecule-1 (uKIM-1), monocyte chemoattractant protein-1 (MCP-1), urinary Dickkopf-3 (uDKK3), uromodulin (urinary uUMOD), serum kidney injury molecule-1 (sKIM-1) and serum uromodulin (sUMOD). A composite outcome of kidney progression or death was recorded during a median follow-up period of 26 months.

Results

Multivariate regression analysis identified sUMOD (β-0.357, P < .001) and uDKK3 (β 0.483, P < .001) as independent predictors of interstitial fibrosis, adjusted for age, estimated glomerular filtration rate (eGFR) and log proteinuria. Elevated levels of MCP-1 [odds ratio 15.61, 95% confidence interval (CI) 3.52-69.20] were associated with a higher risk of cortical interstitial inflammation >10% adjusted for eGFR, log proteinuria and microhematuria. Upper tertiles of uDKK3 were associated with greater eGFR decline during follow-up. Although not a predictor of the composite outcome, doubling of uDKK3 was a predictor of kidney events (hazard ratio 2.26, 95% CI 1.04-4.94) after adjustment for interstitial fibrosis, eGFR and proteinuria.

Conclusions

Tubular markers may have prognostic value in proteinuric kidney disease, correlating with specific histologic parameters and identifying cases at higher risk of CKD progression.

Transcription factor E2F3 activates CDC25B to regulate DNA damage and promote mitoxantrone resistance in stomach adenocarcinoma

BACKGROUND

CDC25B, as a member of the cell cycle regulating protein family, is located in the cytoplasm and is involved in the transition of the cell cycle and mitosis. CDC25B is highly expressed in various tumors and is a newly discovered oncogene. This study aimed to investigate the impact of CDC25B on mitoxantrone resistance in stomach adenocarcinoma (STAD) and its possible mechanisms.

METHODS

This study analyzed the expression of CDC25B and its potential transcription factor E2F3 in STAD, as well as the IC50 values of tumor tissues by bioinformatics analysis. Expression levels of CDC25B and E2F3 in STAD cells were measured by qRT-PCR. MTT was utilized to evaluate cell viability and IC50 values of STAD cells, and comet assay was utilized to analyze the level of DNA damage in STAD cells. Western blot was used to analyze the expression of DNA damage-related proteins. The targeting relationship between E2F3 and CDC25B was validated by dual-luciferase and ChIP assays.

RESULTS

Bioinformatics analysis and molecular experiments showed that CDC25B and E2F3 were highly expressed in STAD, and CDC25B was enriched in the mismatch repair and nucleotide excision repair pathways. The IC50 values of tumor tissues with high expression of CDC25B were relatively high. Dual-luciferase and ChIP assays confirmed that CDC25B could be transcriptionally activated by E2F3. Cell experiments revealed that CDC25B promoted mitoxantrone resistance in STAD cells by regulating DNA damage. Further research found that low expression of E2F3 inhibited mitoxantrone resistance in STAD cells by DNA damage, but overexpression of CDC25B reversed the impact of E2F3 knockdown on mitoxantrone resistance in STAD cells.

CONCLUSION

This study confirmed a novel mechanism by which E2F3/CDC25B mediated DNA damage to promote mitoxantrone resistance in STAD cells, providing a new therapeutic target for STAD treatment.

FOXN Transcription Factors: Regulation and Significant Role in Cancer

A growing number of studies have demonstrated that cancer development is closely linked to abnormal gene expression, including alterations in the transcriptional activity of transcription factors. The Forkhead box class N (FOXN) proteins FOXN1-6 form a highly conserved class of transcription factors, which have been shown in recent years to be involved in the regulation of malignant progression in a variety of cancers. FOXNs mediate cell proliferation, cell-cycle progression, cell differentiation, metabolic homeostasis, embryonic development, DNA damage repair, tumor angiogenesis, and other critical biological processes. Therefore, transcriptional dysregulation of FOXNs can directly affect cellular physiology and promote cancer development. Numerous studies have demonstrated that the transcriptional activity of FOXNs is regulated by protein-protein interactions, microRNAs (miRNA), and posttranslational modifications (PTM). However, the mechanisms underlying the molecular regulation of FOXNs in cancer development are unclear. Here, we reviewed the molecular regulatory mechanisms of FOXNs expression and activity, their role in the malignant progression of tumors, and their value for clinical applications in cancer therapy. This review may help design experimental studies involving FOXN transcription factors, and enhance their therapeutic potential as antitumor targets.

Aberrant expressions of circulating lncRNA NEAT1 and microRNA‐125a are linked with Th2 cells and symptom severity in pediatric allergic rhinitis

Objective

Long noncoding RNA nuclear enriched abundant transcript 1 (lnc‐NEAT1) and its target microRNA‐125a (miR‐125a) are reported to regulate immune and inflammation process in allergic rhinitis (AR). Hence, this study intended to investigate the correlation between lnc‐NEAT1 and miR‐125a expressions, as well as their clinical values in pediatric AR patients.

Methods

Peripheral blood mononuclear cell samples from 80 pediatric AR patients, 40 disease controls (DCs), and 40 healthy controls (HCs) were collected to detect lnc‐NEAT1 and miR‐125a expressions by reverse transcription‐quantitative polymerase chain reaction. For pediatric AR patients only, serum interferon‐gamma (IFN‐γ) and interleukin (IL)‐10 were measured by enzyme linked immunosorbent assay; meanwhile, T helper (Th) 1 and Th2 cells in CD4⁺ T cells were analyzed by flow cytometry.

Results

Lnc‐NEAT1 was overexpressed, while miR‐125a downregulated in pediatric AR patients compared to DCs and HCs (all p < 0.001). Moreover, lnc‐NEAT1 expression negatively correlated with miR‐125a expression in pediatric AR patients (p = 0.002), but not in DCs (p = 0.226) or HCs (p = 0.237). Furthermore, in pediatric AR patients, lnc‐NEAT1 expression positively associated with TNSS (p < 0.001), sneezing score (p = 0.006), and congestion score (p = 0.008); miR‐125a expression was negatively related to TNSS (p < 0.001), itching score (p = 0.040), and sneezing score (p = 0.005). Additionally, lnc‐NEAT1 expression positively, while miR‐125a expression negatively correlated with Th2 cells and IL‐10 (all p < 0.05), but they were not correlated with Th1 cells or IFN‐γ in pediatric AR patients.

Conclusion

Circulating lnc‐NEAT1 and miR‐125a are aberrantly expressed and linked with Th2 cells and symptom severity in pediatric allergic rhinitis.

Circular RNA circ_0000644 promotes papillary thyroid cancer progression via sponging miR-1205 and regulating E2F3 expression

The dysregulation of circular RNAs (circRNAs) facilitates the tumorigenesis of papillary thyroid carcinoma (PTC). This study was targeted at determining the functions and mechanism of circ_0000644 in regulating PTC development. Circ_0000644, microRNA-1205 (miR-1205) and E2F transcription factor 3 (E2F3) expressions were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Actinomycin D (ActD) and Ribonuclease R (RNase R) assays were used to verify the circular characteristic of circ_0000644. After circ_0000644 was knocked down, PTC cell growth, migration, invasion and apoptosis were assessed by cell counting kit-8 (CCK-8) assay, Transwell assay and flow cytometry analysis, respectively. The regulating relationships among circ_0000644, E2F3 and miR-1205 were confirmed through RNA immunoprecipitation (RIP) assay and dual-luciferase reporter assay. Besides, the regulatory effects of circ_0000644 on the protein level of E2F3 was analyzed via Western blot. In PTC, circ_0000644 was highly expressed, and it was located mainly in the cytoplasm, and it had stable structure. The knockdown of circ_0000644 repressed PTC cell growth, migration, and invasion, and facilitated apoptosis. Circ_0000644 could directly interact with miR-1205 to repress the expression of miR-1205, and it served as a miR-1205 sponge to modulate E2F3 expression in PTC cells. Circ_0000644 up-regulates E2F3 expression via sponging miR-1205 to promote PTC progression.

E2F3 promotes liver cancer progression under the regulation of circ-PRKAR1B

Liver cancer is one of the most lethal malignant tumors in the world. The high recurrence and mortality rate make it urgent for scientists and clinicians to find new targets for better treatment of liver cancer. Here, we found that circ-PRKAR1B expression was increased in the paired intrahepatic metastasis sample through high-throughput sequencing. Further experiments also confirmed its high expression both in carcinoma and metastasis when compared to the paired para-carcinoma and the paired carcinoma, respectively. Mechanism study showed that circ-PRKAR1B could promote liver cancer progression through the miR-432-5p/E2F3 pathway, and microRNA-432-5p could directly target the 3' untranslated region (UTR) of E2F3 mRNA to suppress its translation, thereby influencing liver cancer cell invasion and migration capacities. Clinical data obtained by using online databases based on The Cancer Genome Atlas (TCGA) samples and the clinicopathological data of liver cancer patients who underwent surgery in our hospital in the past 2 years also confirmed the significance of circ-PRKAR1B/miR-432-5p/E2F3 signaling in liver cancer progression. Animal experiments also indicated that targeting this newly identified signaling by overexpressing microRNA-432-5p could suppress the progression of liver cancer. Together, our study suggests that circ-PRKAR1B plays an important role in the regulation of liver cancer progression, and targeting this new circ-PRKAR1B/miR-432-5p/E2F3 signaling may help us find new treatment strategies to better suppress liver cancer progression.

Long intergenic non-protein coding RNA 1094 (LINC01094) promotes the progression of breast cancer (BC) by regulating the microRNA-340-5p (miR-340-5p)/E2F transcription factor 3 (E2F3) axis

The present study was targeted at investigating the effects of long intergenic non-protein coding RNA 1094 on breast cancer (BC) cell proliferation, apoptosis, and cell cycle and its related mechanism. In this study, Western blot and quantitative real-time polymerase chain reaction (qRT-PCR) were conducted to detect the expressions of LINC01094, microRNA (miRNA, miR)-340-5p, and E2F transcription factor 3 (E2F3) in BC tissues and cells. With transfection, LINC01094 and miR-340-5p expressions were selectively up-regulated or down-regulated in BC cell lines, and then cell proliferation, cell cycle, and apoptosis were examined by cell counting kit-8 (CCK-8), 5-bromo-2ʹ-deoxyuridine (BrdU), and flow cytometry assays. Bioinformatics was utilized to predict the targeted relationships between miR-340-5p and LINC01094, as well as miR-340-5p and E2F3 mRNA 3ʹ-untranslated region (3ʹUTR), and RNA immunoprecipitation (RIP) assay and dual-luciferase reporter gene assay were employed to validate them. It was revealed that, LINC01094 expression was enhanced in BC cells and tissues, and LINC01094 overexpression promoted BC cell proliferation, accelerated cell cycle progression, and inhibited apoptosis while knocking down LINC01094 worked oppositely. LINC01094 directly targeted miR-340-5p and negatively regulated its expression in BC cells. Besides, E2F3 was substantiated to be the target gene of miR-340-5p, and E2F3 expression could be indirectly and positively modulated by LINC01094. All in all, LINC01094 promotes BC cell proliferation and cell cycle progression and inhibits apoptosis via modulating miR-340-5p/E2F3 molecular axis.

FOXN3 inhibits cell proliferation and invasion via modulating the AKT/MDM2/p53 axis in human glioma

This study aimed to evaluate the biological role of forkhead box N3 (FOXN3) in human glioma and clarify the possible molecular mechanisms. FOXN3 expression patterns in clinical tissue specimens were characterized via qPCR and Western blotting. Kaplan-Meier survival curve was applied to assess the correlation between FOXN3 expression and overall survival. Effects of FOXN3 over-expression and depletion on glioma cell proliferation, apoptosis, migration and invasion were assessed by CCK8, colony formation assay, flow cytometry, scratch wound healing assay and Transwell invasion assay, respectively. Moreover, the involvement of AKT/murine double minute 2 (MDM2)/p53 pathway was evaluated. Additionally, tumor transplantation model assay was performed to determine the effects of FOXN3 over-expression on glioma cell growth in vivo. Results showed that FOXN3 was significantly down-regulated in glioma tissues compared with normal tissues. Patients with lower FOXN3 expression exhibited a shorter overall survival time. Gain- and loss-of-function analyses demonstrated that FOXN3 over-expression significantly suppressed proliferation, survival and motility of glioma cells, whereas FOXN3 knockdown remarkably promoted glioma cell proliferation, survival and motility. Furthermore, FOXN3 over-expression inhibited the activation of AKT/MDM2/p53 signaling pathway in glioma cells, while FOXN3 depletion facilitated its activation. Additionally, tumor xenograft assays revealed that FOXN3 over-expression retarded glioma cell growth in vivo. Collectively, these findings indicate that FOXN3 inhibits cell growth and invasion through inactivating the AKT/MDM2/p53 signaling pathway and that FOXN3-AKT/MDM2/p53 axis may represent a novel therapeutic target for glioma patients.

Decrease of miR-125a-5p in Gastritis and Gastric Cancer and Its Possible Association with H. pylori

PURPOSE

The aim of this study was to evaluate the expression of miR-125a-5p in patients with dyspeptic symptoms and gastric cancer, correlating them with the development of this cancer and H. pylori.

METHODS

Patients were divided in groups according to histopathological analysis (control, gastritis, and cancer groups). Polymerase chain reaction was performed to detect H. pylori and real-time quantitative PCR to determine miR-125a-5p expression.

RESULTS

H. pylori was detected in 44% of the patients, with prevalence in the gastritis and cancer groups. A statistically significant decrease of miR-125a-5p expression was found in the control positive (p = 0.0183*), gastritis positive (p = 0.0380*), and cancer positive (p = 0.0288*) groups when compared with the control negative group.

CONCLUSION

We suggest that decreased expression of the miRNA-125a-5p associated with the presence of the H. pylori is an important mechanism in gastric diseases and could be a possible marker for early diagnosis of gastric cancer.

Comprehensive Analysis of E2F Family Members in Human Gastric Cancer

Gastric cancer (GC) is the second most common cancer and the third most frequent cause of cancer-related deaths in China. E2Fs are a family of transcription factors reported to be involved in the tumor progression of various cancer types; however, the roles of individual E2Fs are still not known exactly in tumor progression of GC. In this study, we examined the expression of E2Fs to investigate their roles in tumor progression in GC patients using multiple databases, including ONCOMINE, GEPIA2, Kaplan-Meier plotter, cBioPortal, Metascape, LinkedOmics, GeneMANIA, STRING and UCSC Xena. We also performed real-time polymerase chain reaction (RT-PCR) to validate the expression levels of individual E2Fs in several GC cell lines. Our results demonstrated that the mRNA levels of E2F1/2/3/5/8 were significantly higher both in GC tissues and cell lines. The expression levels of E2F1 and E2F4 were correlated with poor overall survival (OS), decreased post-progression survival (PPS), and decreased progression-free survival (FP) in patients with GC. However, overexpression of E2F2, E2F5, E2F7 and E2F8 is significantly associated with disease-free survival and overall survival in patients with GC. In addition, higher E2F3 and E2F6 mRNA expression was found to increase GC patients' OS and PPS. 224 of 415 patients with STAD (54%) had gene mutations that were associated with longer disease-free survival (DFS) but not OS. Cell cycle pathway was closely associated with mRNA level of more than half of E2Fs (E2F1/2/3/7/8). There were close and complicated interactions among E2F family members. Finally, our results indicated the gene expressions of E2Fs had a positive relationship with its copy numbers. Taken together, E2F1/2/3/5/8 can serve as biomarkers for GC patients with high prognostic value for OS of GC patients or therapeutic targets for GC.

Circ_0016760 Acts as a Sponge of MicroRNA-4295 to Enhance E2F Transcription Factor 3 Expression and Facilitates Cell Proliferation and Glycolysis in Nonsmall Cell Lung Cancer

Background: Circular RNAs (circRNAs) have been validated as important regulators of nonsmall cell lung cancer (NSCLC), but the role and potential mechanism of circ_0016760 in NSCLC remain largely unclear. Materials and Methods: Quantitative real-time polymerase chain reaction was performed to detect the levels of circ_0016760, microRNA-4295 (miR-4295), and E2F transcription factor 3 (E2F3). The cell proliferation was measured by methyl-thiazolyl diphenyl-tetrazolium bromide assay. The protein levels of proliferating cell nuclear antigen and E2F3 were examined by Western blot. Xenograft mice model was constructed to explore the effect of circ_0016760 on tumor growth in vivo. The relationship among circ_0016760, miR-4295, and E2F3 was evaluated using dual-luciferase reporter assay. Glucose consumption of NSCLC cells was assessed by the glucose assay kit. Results: Circ_0016760 and E2F3 expression levels were upregulated in NSCLC tissues and cells, while miR-4295 was downregulated. Circ_0016760 could bind to miR-4295, and negatively modulate its expression in NSCLC cells. Besides, miR-4295 directly targeted E2F3 and inversely regulated E2F3 expression. More importantly, Circ_0016760 facilitated proliferation and glycolysis of NSCLC cells by increasing E2F3 by sponging miR-4295 as well as promoted the tumor growth in vivo. Conclusion: Circ_0016760 served as a growth-promoting circRNA in NSCLC by facilitating cell proliferation and glycolysis by regulating the miR-4295/E2F3 axis, providing a novel potential target for NSCLC treatment.

Exosomal-lncRNA DLEU1 Accelerates the Proliferation, Migration, and Invasion of Endometrial Carcinoma Cells by Regulating microRNA-E2F3

Purpose

Long non-coding RNAs (lncRNAs) may act as oncogenes in several cancers, including endometrial carcinoma (EC). The purpose of the current study is to investigate the regulatory mechanism of exosomal-lncRNA deleted in lymphocytic leukemia1 (DLEU1) on EC.

Methods

The expression levels of lncRNA DLEU1, microRNA-381-3p and E2F Transcription Factor 3 (E2F3) in EC tissues or cells were detected using quantitative reverse transcription–polymerase chain reaction (qRT-PCR). We then analysed the proliferation, migration, and invasion of EC cells by performing the MTT assay, wound healing assay, and transwell invasion assay, respectively. Identification of exosomes was detected using Western blot assay. The uptake of exosomes was detected by a confocal microscope. The effects of exosomes on EC cells were investigated by construction of cell co-culture system. The interactions among DLEU1, miR-381-3p and E2F3 were confirmed using the dual-luciferase reporter (DLR) assay.

Results

LncRNA DLEU1 expression was highly up-regulated in EC tissues and cells. Knockdown of DLEU1 inhibited the proliferation, migration, and invasion of EC cells. Exosomes could be uptaken by the ambient EC cells. MiR-381-3p was a target of DLEU1 and was negatively modulated by DLEU1. Overexpression of miR-381-3p suppressed the proliferation, migration, and invasion of EC cells. Additionally, E2F3 was the target gene of miR-381-3p and was negatively modulated by miR-381-3p. Upregulation of miR-381-3p and down-regulation of E2F3 reversed the promoting effect of exosomal DLEU1 on EC cells.

Conclusion

Exosomal DLEU1 accelerates the development of EC by regulating the miR-381-3p/E2F3 axis, thus DLEU1 may act as a possible therapeutic target for treating EC.

HNF1A-Induced lncRNA HCG18 Facilitates Gastric Cancer Progression by Upregulating DNAJB12 via miR-152-3p

Background

The aberrant expression of long non-coding RNAs (lncRNAs) plays a pivotal role in the development and progression of multiple cancers, including gastric cancer (GC). However, the underlying molecular mechanisms of lncRNA HCG18 in GC remain unknown.

Materials and Methods

The expression levels of HCG18, HNF1A, microRNA-152-3p (miR-152-3p), and DNAJB12 were determined by RT-qPCR. Cell viability, migration, and invasion were assessed by CCK-8, wound healing, and transwell assays, respectively. The interaction between miR-152-3p and HCG18 or DNAJB12 was predicted by bioinformatics analysis and verified by dual-luciferase reporter assay. The correlation between the gene expression levels was analyzed using Pearson’s correlation coefficient. Western blot was used to measure the levels of HNF1A, DNAJB12, epithelial-mesenchymal transition (EMT) proteins (E-cadherin and Vimentin), and proliferation-related protein (PCNA).

Results

It was found that HCG18 was upregulated in GC tissues and cell lines, and knockdown of HCG18 inhibited the proliferation, migration, and invasion of GC cells. Patients with high HCG18 expression had a shorter overall survival time compared with those with low HCG18 expression. In addition, transcription factor HNF1A could bind to the HCG18 promoter to facilitate its transcription. The upregulation of HCG18 could abolish the inhibitory effect of miR-152-3p overexpression on GC cell progression. Furthermore, DNAJB12 was demonstrated to be a target gene of miR-152-3p in GC cells, and HCG18 enhanced DNAJB12 expression by competitively binding with miR-152-3p. Finally, rescue assays proved that overexpression of DNAJB12 partially restored HCG18 knockdown-attenuated progression of GC cells.

Conclusion

Our results demonstrated that HNF1A-induced HCG18 overexpression promoted GC progression by competitively binding with miR-152-3p and upregulating DNAJB12 expression. These findings might provide potential treatment strategies for patients with GC.

Downregulation of miRNA-126-3p is associated with progression of and poor prognosis for lung squamous cell carcinoma

Lung squamous cell carcinoma (LUSC) is the main pathological type of pulmonary malignant tumors; at present, less than 10% of patients with advanced metastatic LUSC live for more than 5 years. We previously reported that low expression of miRNA-126-3p is associated with the occurrence and progression of lung adenocarcinoma (LUAD). Here, we examined expression of miRNA-126-3p in 23 samples from patients with LUSCs and 23 normal control specimens by quantitative real-time PCR (RT-qPCR). Associations between miRNA-126-3p expression and clinical features were studied from materials derived from Gene Expression Omnibus (GEO) chips and The Cancer Genome Atlas (TCGA) database. Twelve online platforms were used to identify candidate target genes of miRNA-126-3p. Further analyses of the Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO), and protein-protein interaction (PPI) network were performed on the target genes. GEO microarray analysis, TCGA data mining, RT-qPCR, and integration analysis consistently reported low expression of miRNA-126-3p in LUSC. A total of 42 genes were identified as potential target genes of miRNA-126-3p from online platforms, GEO microarrays, and the TCGA database. GO and KEGG analyses demonstrated that the target genes are involved in several biological processes that promote the progression of LUSC. SOX2, E2F2, and E2F3 were selected as hub genes from the PPI network for further analysis. In summary, our results suggest that the low expression of miRNA-126-3p may play a role in promoting the development of LUSC and miRNA-126-3p may be a biomarker for LUSC early diagnosis and prognosis.

CircPIP5K1A activates KRT80 and PI3K/AKT pathway to promote gastric cancer development through sponging miR-671-5p

BACKGROUND

Gastric cancer (GC) has been regarded as a kind of the most common cancers in gastrointestinal malignant tumors. Circular RNA (circRNA) is a newly discovered category of non-coding RNAs and plays a significant role in the initiation or development of human cancers. Nevertheless, the role of circPIP5K1A in GC remains unclear.

METHODS

The relative expression level and the circular structure of circPIP5K1A were confirmedby RT-qPCR. The biological function of circPIP5K1A in GC was evaluated by colony formation, transwell and western blot assays. The binding capacity between miR-671-5p and circPIP5K1A (or KRT80) was assessed by luciferase reporter and Ago2-RIP assays. Protein levels of PI3K/AKT pathway were measured by western blot assay.

RESULTS

CircPIP5K1A was up-regulated in GC tissues and cells with a circular structure. Functionally, circPIP5K1A silence limited cell proliferation, invasion, migration and EMT process. Mechanistically, circPIP5K1A directly interacted with miR-671-5p to modulate KRT80 expression. Either miR-671-5p inhibitor or KRT80 overexpression could offset the inhibitory effect of circPIP5K1A depletion on GC development. Besides, circPIP5K1A played its oncogenic role in GC through regulating PI3K/AKT pathway. At last, circPIP5K1A promoted GC tumor growth in vivo.

CONCLUSIONS

CircPIP5K1A/miR-671-5p/KRT80 axis contributes to GC progression through PI3K/AKT pathway, implying this axis may be a potential therapeutic target for the treatment of GC patients.

Upregulation of miR-34c after silencing E2F transcription factor 1 inhibits paclitaxel combined with cisplatin resistance in gastric cancer cells

BACKGROUND

MicroRNA 34c (miR-34c) has been reported to be associated with malignant types of cancer, however, it remains unknown whether miR-34c is involved in chemoresistance in gastric cancer (GC).

AIM

To investigate the effect of miR-34c and its upstream transcription factor E2F1 on paclitaxel combined with cisplatin resistance in GC cells.

METHODS

Paired GC tissues and adjacent normal tissues were randomly sampled from 74 GC patients. miR-34c and E2F1 were detected by real-time quantitative PCR (qPCR) and Western blot. In addition, the drug resistance of GC cells to paclitaxel and cisplatin was induced by concentration gradient increasing methods, and changes in miR-34c and E2F1 during this process were measured. Furthermore, E2F1 and miR-34c overexpression or underexpression vectors were constructed and transfected into drug-resistant GC cells. MTT was employed to test the sensitivity of cells to paclitaxel combined with cisplatin, qPCR was adopted to detect the expression of miR-34c, Western blot was applied to detect the expression levels of E2F1, drug resistance-related proteins and apoptosis-related proteins, and flow cytometry was used for the determination of cell apoptosis and cell cycle status.

RESULTS

E2F1 was overexpressed while miR-34c was underexpressed in GC. After inducing GC cells to be resistant to paclitaxel and cisplatin, E2F1 expression increased while miR-34c expression decreased. Both silencing E2F1 and over-expressing miR-34c could increase the sensitivity of drug-resistant GC cells to paclitaxel combined with cisplatin, promote cell apoptosis and inhibit cell proliferation. Among which, silencing E2F1 could reduce the expression of drug resistance-related proteins and apoptosis-related proteins, while over-expression of miR-34c could upregulate the expression of apoptosis-related proteins without affecting the expression of MDR-1, MRP and other drug resistance-related proteins. Rescue experiments demonstrated that inhibiting miR-34c could significantly weaken the sensitization of drug resistant cells, and Si E2F1 to paclitaxel combined with cisplatin.

CONCLUSION

E2F1 inhibits miR-34c to promote the proliferation of GC cells and enhance the resistance to paclitaxel combined with cisplatin, and silencing E2F1 is conducive to improving the efficacy of paclitaxel combined with cisplatin in GC cells.

MicroRNA-432 Suppresses Invasion and Migration via E2F3 in Nasopharyngeal Carcinoma

Background

E2F transcription factor 3 (E2F3) is oncogenic and dysregulated in various malignancies. Complex networks involving microRNAs (miRNAs) and E2F3 regulate tumorigenesis and progression. However, the potential roles of E2F3 and its target miRNAs in nasopharyngeal carcinoma (NPC) are rarely reported.

Methods

E2F3 expression was detected in human NPC tissues and cell lines through quantitative real-time PCR. NPC cell proliferation, migration, and invasion were evaluated in vitro by colony forming, cell counting kit-8, wound healing, and Transwell invasion assays. Publicly available database software was used to explore the target miRNAs of E2F3. Dual-luciferase reporter assay was performed to identify the direct relationship. The function of miRNAs in vivo was investigated by using a tumor xenograft model.

Results

E2F3 was upregulated in NPC cell lines and tissues, and its exotic expression promoted NPC cell invasion and migration. E2F3 was identified as a target of miR-432, which restrained NPC cell invasion and migration in vitro and in vivo. Further experiments revealed that miR-432 repressed the invasion and migration potential of NPC cells by modulating E2F3 expression.

Conclusion

miRNA-432 suppressed the malignant biological behavior of NPC cells by targeting E2F3. This study provided further insights into NPC prognosis and treatment.