miR-335-5p suppresses gastric cancer progression by targeting MAPK10

Dual DNAzyme amplification-based colorimetric sensing assay for the identification and quantification of tumor-associated miRNAs

Herein, we present a colorimetric sensing strategy for the identification and quantification of tumor-associated miRNAs based on dual DNAzyme amplification. In this sensing ensemble, the substrate portion of the Pb2+-dependent 8-17 DNAzyme combines with the G-quadruplex portion to form a hairpin substrate strand. The two split 8-17 DNAzyme strands are partially complementary to the substrate strand and serve as a recognition unit for binding the target miRNA. In the presence of the target miRNA, the activated DNAzyme cleaves the substrate strand, releasing the G-quadruplex. This G-quadruplex binds to hemin to form a G-quadruplex/hemin complex with horseradish peroxidase (HRP)-like properties, which catalyzes the oxidation of ABTS2- by H2O2. This oxidation reaction produces a colorimetric signal output, enabling the detection of the target miRNA. Under the optimal reaction conditions explored in this study, the constructed sensing ensembles tailored for each of the specific target miRNAs successfully identified and quantified the four target miRNAs-miR-122, miR-21, miR-335, and miR-155-in both buffer solutions and cell extracts. This colorimetric sensing strategy offers significant advantages in terms of simplicity, cost, and versatility and holds great potential for wide application in biomedical research and clinical diagnostics.

Metabolomics and network pharmacology-based identification of phenolic acids in Polygonatum kingianum var. grandifolium rhizomes as anti-cancer/Tumor active ingredients

Broadly targeted metabolomics techniques were used to identify phenolic acid compounds in Polygonatum kingianum var. grandifolium (PKVG) rhizomes and retrieve anti-cancer/tumor active substance bases from them. We identified potential drug targets by constructing Venn diagrams of compound and disease targets. Further, KEGG pathway analysis was performed to reveal the relevant pathways for anti-cancer/tumor activity of PKVG. Finally, we performed molecular docking to determine whether the identified proteins were targets of phenolic acid compounds from PKVG rhizome parts. The study's results revealed 71 phenolic acid compounds in PKVG rhizomes. Among them, three active ingredients and 42 corresponding targets were closely related to the anticancer/tumor activities of PKVG rhizome site phenolic acids. We identified two essential compounds and eight important targets by constructing the compound-target pathway network. 2 essential compounds were androsin and chlorogenic acid; 8 key targets were MAPK1, EGFR, PRKCA, MAPK10, GSK3B, CASP3, CASP8, and MMP9. The analysis of the KEGG pathway identified 42 anti-cancer/tumor-related pathways. In order of degree, we performed molecular docking on two essential compounds and the top 4 targets, MAPK1, EGFR, PRKCA, and MAPK10, to further validate the network pharmacology screening results. The molecular docking results were consistent with the network pharmacology results. Therefore, we suggest that the phenolic acids in PKVG rhizomes may exert anti-cancer/tumor activity through a multi-component, multi-target, and multi-channel mechanism of action.

miR-1286, a Tumor Suppressor of Gastric Cancer, Serves as a Promising Biomarker for Screening Gastric Cancer from Gastritis

Gastric cancer (GC) is one of the crucial causes of cancer-associated death worldwide. This study aimed to investigate the biological function of miR-1286 in GC progression in vitro, evaluate the clinical value of serum miR-1286 to screen GC patients and explore its relationship with helicobacter pylori (HP) infection and peritoneal metastasis in GC patients. Expression of miR-1286 was measured by RT-qPCR. Cell Counting Kit-8 assay was utilized for measuring GC cell proliferation ability. The migration and invasion abilities of GC cells were measured using Transwell assays. Serum samples were obtained from 108 GC patients, 62 gastritis cases and 62 healthy volunteers. The diagnostic performance of miR-1286 was assessed using ROC analysis, and the predictive value of miR-1286 for peritoneal metastasis onset was analyzed using logistic regression analysis. miR-1286 played as a tumor suppressor in GC progression by inhibiting GC cell proliferation, migration and invasion. In GC patients, significantly decreased miR-1286 was observed compared to gastritis and healthy controls, and had considerable diagnostic accuracy to distinguish GC from the controls. A significant association was found between miR-1286 expression and HP infection, peritoneal metastasis and TNM stage. Moreover, miR-1286 was lowly expressed in GC patients with peritoneal metastasis, and independently predicted the occurrence of peritoneal metastasis in GC. miR-1286 acts as a tumor suppressor and a biomarker in GC, and is closely associated with HP infection and peritoneal metastasis onset. The methods to regulate miR-1286 may be novel strategies to improve the treatment of GC.

Loss of ADAR1 induces ferroptosis of breast cancer cells

Adenosine deaminases acting on RNA 1(ADAR1), an RNA editing enzyme that converts adenosine to inosine by deamination in double-stranded RNAs, plays an important role in occurrence and progression of various types of cancer. Ferroptosis has emerged as a hot topic of cancer research in recent years. We have previously reported that ADAR1 promotes breast cancer progression by regulating miR-335-5p and METTL3. However, whether ADAR1 has effects on ferroptosis in breast cancer cells is largely unknown. In this study, we knocked down ADAR1 using CRISPR-Cas9 technology or over-expressed ADAR1 protein using plasmid expressing ADAR1 in MCF-7 and MDA-MB-231 breast cancer cell lines, then detected cell viability, and levels of ROS, MDA, GSH, Fe2+, GPX4 protein and miR-335-5p. We showed that the cell proliferation was inhibited, levels of ROS, MDA, Fe2+, and miR-335-5p were increased, while GSH and GPX4 levels were decreased after loss of ADAR1, compared to the control group. The opposite effects were observed after ADAR1 overexpression in the cells. Further, we demonstrated that ADAR1-controlled miR-335-5p targeted Sp1 transcription factor of GPX4, a known ferroptosis molecular marker, leading to inhibition of ferroptosis by ADAR1 in breast cancer cells. Moreover, RNA editing activity of ADAR1 is not essential for inducing ferroptosis. Collectively, loss of ADAR1 induces ferroptosis in breast cancer cells by regulating miR-335-5p/Sp1/GPX4 pathway. The findings may provide insights into the mechanism by which ADAR1 promotes breast cancer progression via inhibiting ferroptosis.

Three-Dimensional Mechanical Microenvironment Rescued the Decline of Osteogenic Differentiation of Old Human Jaw Bone Marrow Mesenchymal Stem Cells

Resorption and atrophy of the alveolar bone, as two consequences of osteoporosis that remarkably complicate the orthodontic and prosthodontic treatments, contribute to the differentiated biological features and force-induced response of jaw bone marrow-derived mesenchymal stem cells (JBMSCs) in elderly patients. We isolated and cultured JBMSCs from adolescent and adult patients and then simulated the loading of orthodontic tension stress by constructing an in vitro three-dimensional (3D) stress loading model. The decline in osteogenic differentiation of aged JBMSCs was reversed by tensile stress stimulation. It is interesting to note that tension stimulation had a stronger effect on the osteogenic differentiation of elderly JBMSCs compared to the young ones, indicating a possible mechanism of aging rescue. High-throughput sequencing of microRNA (miRNAs) was subsequently performed before and after tension stimulation in all JBMSCs, followed by the comprehensive comparison of mechanically responsive miRNAs in the 3D strain microenvironment. The results suggested a significant reduction in the expression of miR-210-3p and miR-214-3p triggered by the 3D strain microenvironment in old-JBMSCs. Bioinformatic analysis indicated that both miRNAs participate in the regulation of critical pathways of aging and cellular senescence. Taken together, this study demonstrated that the 3D strain microenvironment efficiently rescued the cellular senescence of old-JBMSCs via modulating specific miRNAs, which provides a novel strategy for coordinating periodontal bone loss and regeneration of the elderly.

Construction of ceRNA regulatory networks for active pulmonary tuberculosis

Delayed diagnosis in patients with pulmonary tuberculosis (PTB) often leads to serious public health problems. High throughput sequencing was used to determine the expression levels of lncRNAs, mRNAs, and miRNAs in the lesions and adjacent health lung tissues of patients with PTB. Their differential expression profiles between the two groups were compared, and 146 DElncRs, 447 DEmRs, and 29 DEmiRs were obtained between lesions and adjacent health tissues in patients with PTB. Enrichment analysis for mRNAs showed that they were mainly involved in Th1, Th2, and Th17 cell differentiation. The lncRNAs, mRNAs with target relationship with miRNAs were predicted respectively, and correlation analysis was performed. The ceRNA regulatory network was obtained by comparing with the differentially expressed transcripts (DElncRs, DEmRs, DEmiRs), then 2 lncRNAs mediated ceRNA networks were established. The expression of genes within the network was verified by quantitative real-time PCR (qRT-PCR). Flow cytometric analysis revealed that the proportion of Th1 cells and Th17 cells was lower in PTB than in controls, while the proportion of Th2 cells increased. Our results provide rich transcriptome data for a deeper investigation of PTB. The ceRNA regulatory network we obtained may be instructive for the diagnosis and treatment of PTB.

Molecular characteristics and therapeutic implications of Toll-like receptor signaling pathway in melanoma

Melanoma is a malignant tumor of melanocytes and is often considered immunogenic cancer. Toll-like receptor-related genes are expressed differently in most types of cancer, depending on the immune microenvironment inside cancer, and the key function of Toll-like receptors (TLRs) for melanoma has not been fully elucidated. Based on multi-omics data from TCGA and GEO databases, we first performed pan-cancer analysis on TLR, including CNV, SNV, and mRNA changes in TLR-related genes in multiple human cancers, as well as patient prognosis characterization. Then, we divided melanoma patients into three subgroups (clusters 1, 2, and 3) according to the expression of the TLR pathway, and explored the correlation between TLR pathway and melanoma prognosis, immune infiltration, metabolic reprogramming, and oncogene expression characteristics. Finally, through univariate Cox regression analysis and LASSO algorithm, we selected six TLR-related genes to construct a survival prognostic model, divided melanoma patients into the training set, internal validation set 1, internal validation set 2, and external validation set for multiple validations, and discussed the correlation between model genes and clinical features of melanoma patients. In conclusion, we constructed a prognostic survival model based on TLR-related genes that precisely and independently demonstrated the potential to assess the prognosis and immune traits of melanoma patients, which is critical for patients' survival.

Construction and Identification of an NLR-Associated Prognostic Signature Revealing the Heterogeneous Immune Response in Skin Cutaneous Melanoma

Background

Skin cutaneous melanoma (SKCM) is the deadliest dermatology tumor. Ongoing researches have confirmed that the NOD-like receptors (NLRs) family are crucial in driving carcinogenesis. However, the function of NLRs signaling pathway-related genes in SKCM remains unclear.

Objective

To establish and identify an NLRs-related prognostic signature and to explore its predictive power for heterogeneous immune response in SKCM patients.

Methods

Establishment of the predictive signature using the NLRs-related genes by least absolute shrinkage and selection operator-Cox regression analysis (LASSO-COX algorithm). Through univariate and multivariate COX analyses, NLRs signature's independent predictive effectiveness was proven. CIBERSORT examined the comparative infiltration ratios of 22 distinct types of immune cells. RT-qPCR and immunohistochemistry implemented expression validation for critical NLRs-related prognostic genes in clinical samples.

Results

The prognostic signature, including 7 genes, was obtained by the LASSO-Cox algorithm. In TCGA and validation cohorts, SKCM patients with higher risk scores had remarkably poorer overall survival. The independent predictive role of this signature was confirmed by multivariate Cox analysis. Additionally, a graphic nomogram demonstrated that the risk score of the NLRs signature has high predictive accuracy. SKCM patients in the low-risk group revealed a distinct immune microenvironment characterized by the significantly activated inflammatory response, interferon-α/γ response, and complement pathways. Indeed, several anti-tumor immune cell types were significantly accumulated in the low-risk group, including M1 macrophage, CD8 T cell, and activated NK cell. It is worth noting that our NLRs prognostic signature could serve as one of the promising biomarkers for predicting response rates to immune checkpoint blockade (ICB) therapy. Furthermore, the results of expression validation (RT-qPCR and IHC) were consistent with the previous analysis.

Conclusion

A promising NLRs signature with excellent predictive efficacy for SKCM was developed.

NF-κB Signaling Modulates miR-452-5p and miR-335-5p Expression to Functionally Decrease Epithelial Ovarian Cancer Progression in Tumor-Initiating Cells

Epithelial ovarian cancer (EOC) remains the fifth leading cause of cancer-related death in women worldwide, partly due to the survival of chemoresistant, stem-like tumor-initiating cells (TICs) that promote disease relapse. We previously described a role for the NF-κB pathway in promoting TIC chemoresistance and survival through NF-κB transcription factors (TFs) RelA and RelB, which regulate genes important for the inflammatory response and those associated with cancer, including microRNAs (miRNAs). We hypothesized that NF-κB signaling differentially regulates miRNA expression through RelA and RelB to support TIC persistence. Inducible shRNA was stably expressed in OV90 cells to knockdown RELA or RELB; miR-seq analyses identified differentially expressed miRNAs hsa-miR-452-5p and hsa-miR-335-5p in cells grown in TIC versus adherent conditions. We validated the miR-seq findings via qPCR in TIC or adherent conditions with RELA or RELB knocked-down. We confirmed decreased expression of hsa-miR-452-5p when either RELA or RELB were depleted and increased expression of hsa-miR-335-5p when RELA was depleted. Either inhibiting miR-452-5p or mimicking miR-335-5p functionally decreased the stem-like potential of the TICs. These results highlight a novel role of NF-κB TFs in modulating miRNA expression in EOC cells, thus opening a better understanding toward preventing recurrence of EOC.

Identification and characterization of bone/cartilage-associated signatures in common fibrotic skin diseases

Background: Fibrotic skin diseases are characterized by excessive accumulation of the extracellular matrix (ECM) and activation of fibroblasts, leading to a global healthcare burden. However, effective treatments of fibrotic skin diseases remain limited, and their pathological mechanisms require further investigation. This study aims to investigate the common biomarkers and therapeutic targets in two major fibrotic skin diseases, namely, keloid and systemic sclerosis (SSc), by bioinformatics analysis.

Methods: The keloid (GSE92566) and SSc (GSE95065) datasets were downloaded from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were identified, followed by functional enrichment analysis using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). We then constructed a protein–protein interaction (PPI) network for the identification of hub genes. We explored the possibility of further functional enrichment analysis of hub genes on the Metascape, GeneMANIA, and TissueNexus platforms. Transcription factor (TF)–hub gene and miRNA–hub gene networks were established using NetworkAnalyst. We fixed GSE90051 and GSE76855 as the external validation datasets. Student’s t-test and receiver operating characteristic (ROC) curve were used for candidate hub gene validation. Hub gene expression was assessed in vitro by quantitative real-time PCR.

Results: A total of 157 overlapping DEGs (ODEGs) were retrieved from the GSE92566 and GSE95065 datasets, and five hub genes (COL11A1, COL5A2, ASPN, COL10A1, and COMP) were identified and validated. Functional studies revealed that hub genes were predominantly enriched in bone/cartilage-related and collagen-related processes. FOXC1 and miR-335-5p were predicted to be master regulators at both transcriptional and post‐transcriptional levels.

Conclusion: COL11A1, COL5A2, ASPN, COL10A1, and COMP may help understand the pathological mechanism of the major fibrotic skin diseases; moreover, FOXC1 and miR-355-5p could build a regulatory network in keloid and SSc.

Downregulation of circ-ZNF644 alleviates LPS-induced HK2 cell injury via miR-335-5p/HIPK1 axis

Circular RNA (circRNA) has been confirmed to be involved in regulating sepsis-induced acute kidney injury (AKI). Our research aims to explore circ-ZNF644 role in the development of sepsis-induced AKI. Lipopolysaccharide (LPS) was used to induce kidney tubular epithelial cell (HK2) injury. ELISA assay was performed to measure the concentrations of inflammation factors. Cell functions were determined by cell counting kit 8 assay, EdU assay and flow cytometry. Protein expression was evaluated by Western blot analysis. Quantitative real-time PCR was used to detect relative expression of circ-ZNF644, miR-335-5p and homeodomain-interacting protein kinase 1 (HIPK1). RNA interaction was confirmed by dual-luciferase reporter assay and RIP assay. LPS enhanced HK2 cell inflammation, oxidative stress, apoptosis, and reduced proliferation. Circ-ZNF644 was overexpressed in sepsis-induced AKI patients. Circ-ZNF644 knockdown suppressed LPS-induced HK2 cell injury, and this effect could be revoked by miR-335-5p inhibitor. MiR-335-5p was sponged by circ-ZNF644, and its expression was downregulated in sepsis-induced AKI patients. HIPK1 was targeted by miR-335-5p, and its expression could be suppressed by circ-ZNF644 knockdown. MiR-335-5p had an inhibition effect on HK2 cell injury induced by LPS, and HIPK1 overexpression could reverse this effect. Circ-ZNF644 knockdown relieved LPS-induced HK2 cell injury through the miR-335-5p/HIPK1 axis, confirming that circ-ZNF644 contributed to sepsis-induced AKI.

Establishment of a Novel Prognostic Prediction Model for Gastric Cancer Based on Necroptosis-Related Genes

Background: Necroptosis plays a crucial role in the progression of multiple types of cancer. However, the role of necroptosis in gastric cancer (GC) remains unclear. The aim of this study is to establish a necroptosis-related prediction model, which could provide information for treatment monitoring.

Methods: The TCGA-STAD cohort was employed to establish a prognostic prediction signature and the GEO dataset was employed for external validation. The correlation between the risk score and the immune landscape, tumor mutational burden (TMB), microsatellite instability (MSI), as well as therapeutic responses of different therapies were analyzed.

Results: We constructed a prognostic model based on necroptosis-associated genes (NAGs), and its favorable predictive ability was confirmed in an external cohort. The risk score was confirmed as an independent determinant, and a nomogram was further established for prognosis. A high score implies higher tumor immune microenvironment (TIME) scores and more significant TIME cell infiltration. High-risk patients presented with lower TMB, and low-TMB patients had worse overall survival (OS). Meanwhile, Low-risk scores are characterized by MSI-high (MSI-H), lower Tumor Immune Dysfunction and Exclusion (TIDE) score, and higher immunogenicity in immunophenoscore (IPS) analysis.

Conclusion: The developed NAG score provides a novel and effective method for predicting the outcome of GC as well as potential targets for further research.

Elevated mir-145-5p is associated with skeletal muscle dysfunction and triggers apoptotic cell death in C2C12 myotubes

Skeletal muscle dysfunction is a common comorbidity of chronic obstructive pulmonary disease (COPD), and the molecular mechanisms regarding to the pathogenesis of this disease have not been elucidated. In this study, a novel miR-145-5p was significantly upregulated in the serum collected from patients with COPD-associated muscle atrophy, in contrast with the normal participants. Then, we evidenced that silencing of miR-145-5p suppressed cell death and elongated cell survival during cell culture process. Consistently, upregulation of miR-145-5p induced cell apoptosis and restrain cell viability in the C2C12 cells, suggesting that miR-145-5p contributes to cell death. Further experiments evidenced that miR-145-5p decreased the expression levels of phosphorylated PI3K (p-PI3K), Akt (p-Akt) and mTOR (p-mTOR) to inactivate the PI3K/Akt/mTOR pathway, and this pathway was also reactivated by miR-145-5p ablation. Finally, we proved that the protective effects of miR-145-5p ablation were abrogated by co-treating cells with PI3K inhibitor LY294002. Taken together, we concluded that miR-145-5p promoted cell death to facilitate muscle dysfunctions via inactivating the PI3K/Akt/mTOR pathway.

Reconstruction of tissue-specific genome-scale metabolic models for human cancer stem cells

Cancer Stem Cells (CSCs) contribute to cancer aggressiveness, metastasis, chemo/radio-therapy resistance, and tumor recurrence. Recent studies emphasized the importance of metabolic reprogramming of CSCs for the maintenance and progression of the cancer phenotype through both the fulfillment of the energetic requirements and the supply of substrates fundamental for fast-cell growth, as well as through metabolite-induced epigenetic regulation. Therefore, it is of paramount importance to develop therapeutic strategies tailored to target the metabolism of CSCs. In this work, we built computational Genome-Scale Metabolic Models (GSMMs) for CSCs of different tissues. Flux simulations were then used to predict metabolic phenotypes, identify potential therapeutic targets, and spot already-known Transcription Factors (TFs), miRNAs and antimetabolites that could be used as part of drug repurposing strategies against cancer. Results were in accordance with experimental evidence, provided insights of new metabolic mechanisms for already known agents, and allowed for the identification of potential new targets and compounds that could be interesting for further in vitro and in vivo validation.

Tumour suppressor role of microRNA-335-5p in esophageal squamous cell carcinoma by targeting TTK (Mps1)

BACKGROUND

Esophageal cancer is an aggressive malignancy. miR-335-5p is reported to possess both tumour suppressor and tumour promoter activities in different cancers.

OBJECTIVES

We investigated the role of miR-335-5p in esophageal cancer by expression and functional studies.

MATERIALS AND METHODS

The role of miR-335-5p in ESCC was evaluated using MTT assay, cell cycle analysis, colony formation assay, scratch assay, matrigel invasion, and migration assay.

RESULTS

Our expression studies showed a significantly decreased expression of tissue and circulating miR-335-5p in esophageal cancer. Our results herein report a key tumour suppressive role of miR-335-5p in esophageal carcinogenesis by inhibiting proliferation, migration, and invasion in ESCC cells. Using RNA-seq and Insilico analysis we found TTK to be a newly identified direct target and confirmed it by using luciferase assay.

CONCLUSION

Overall, our expression and functional analysis results demonstrated herein point towards the potential role of miR-335-5p in esophageal tumorigenesis. Moreover, this is the first report showing TTK as a downstream target of miR-335-5p.

LncRNA DARS-AS1 aggravates the growth and metastasis of hepatocellular carcinoma via regulating the miR-3200-5p-Cytoskeleton associated protein 2 (CKAP2) axis

Accumulating signs have found that long noncoding RNAs (lncRNAs) contribute to hepatocellular carcinoma (HCC). Here, we probed the effect and mechanism of lncRNA DARS-AS1 in HCC. The profiles of DARS-AS1 and Cytoskeleton associated protein 2 (CKAP2) in 50 HCC tissues and non-tumor tissues were examined by real-time quantitative polymerase chain reaction (RT-qPCR). DARS-AS1 and CKAP2 overexpression and/or knockdown cell models were established. The proliferation, apoptosis, invasion and epithelial-mesenchymal transition (EMT) were determined. CKAP2, and focal adhesion kinase (FAK)-extracellular signal-regulated kinase (ERK) was tested by Western blot (WB). The relationship between DARS-AS1 and CKAP2 was predicted by Bioinformatics, and the dual-luciferase reporter assay was applied to verify the targeting association between miR-3200-5p and DARS-AS1 and CKAP2. DARS-AS1 was overexpressed in HCC tissues (vs. that in non-tumor tissues) and was closely correlated with the patients’ tumor stage. DARS-AS1 facilitated HCC cell proliferation and hampered apoptosis. HCC cell migration and EMT were enhanced by DARS-AS1. DARS-AS1 up-regulated CKAP2, which aggravated HCC. Further investigation illustrated that either DARS-AS1 or CKAP2 activated FAK-ERK pathway, and miR-3200-5p was competitively restrained by DARS-AS1. miR-3200-5p exerted tumor-suppressive effects in HCC and inactivated CKAP2 and FAK-ERK pathway. All in all, this study corroborates that DARS-AS1 facilitates HCC proliferation and metastasis by regulating miR-3200-5p-mediated CKAP2, which provides a potential target for HCC diagnosis and treatment.

Abbreviations: CCK-8: cell counting kit-8; CKAP2: Cytoskeleton associated protein 2; cDNA:complementary DNA; DAPI: 4ʹ,6-diamidino-2-phenylindole; DARS-AS1: DARS1 antisense RNA 1; DEPC: diethyl pyrocarbonate; DMEM-F12: Dulbecco’s minimal essential medium/Ham’s-F12; EMT: epithelial-mesenchymal transition; ERK: extracellular signal-regulated kinase; FAK: focal adhesion kinase; FBS: fetal bovine serum; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; HCC: hepatocellular carcinoma; HE: hematoxylin-eosin; IHC: Immunohistochemistry; LIHC: Liver hepatocellular carcinoma; lncRNAs: long noncoding RNAs; MIAT: lncRNA myocardial infarction-related transcripts; MT: Mutant; NC: negative control; PBS: phosphate-buffered saline; PMSF: Phenylmethylsulfonyl fluoride; PVDF: polyvinylidene difluoride; RT: room temperature; RT-qPCR: real-time quantitative polymerase chain reaction; SDS-PAGE: sodium dodecyl sulfate-polyacrylamide gel electrophoresis; SPF: specific pathogen-free; TMAP: tumor-associated microtubule-associated protein; TUNEL: TdT-mediated dUTP nick end labeling; V: volume; WT: wild type.

CRISPR/Cas9 uPAR Gene Knockout Results in Tumor Growth Inhibition, EGFR Downregulation and Induction of Stemness Markers in Melanoma and Colon Carcinoma Cell Lines

uPAR is a globular protein, tethered to the cell membrane by a GPI-anchor involved in several cancer-related properties and its overexpression commonly correlates with poor prognosis and metastasis. We investigated the consequences of uPAR irreversible loss in human melanoma and colon cancer cell lines, knocking out its expression by CRISPR/Cas9. We analyzed through flow cytometry, western blotting and qPCR, the modulation of the most known cancer stem cells-associated genes and the EGFR while we observed the proliferation rate exploiting 2D and 3D cellular models. We also generated uPAR “rescue” expression cell lines as well as we promoted the expression of only its 3’UTR to demonstrate the involvement of uPAR mRNA in tumor progression. Knocking out PLAUR, uPAR-encoding gene, we observed an inhibited growth ratio unexpectedly coupled with a significant percentage of cells acquiring a stem-like phenotype. In vivo experiments demonstrated that uPAR loss completely abrogates tumorigenesis despite the gained stem-like profile. Nonetheless, we proved that the reintroduction of the 3’UTR of PLAUR gene was sufficient to restore the wild-type status validating the hypothesis that such a region may act as a “molecular sponge”. In particular miR146a, by binding PLAUR 3’ UTR region might be responsible for uPAR-dependent inhibition of EGFR expression.

LncRNA SNHG8 Promotes Proliferation and Inhibits Apoptosis of Diffuse Large B-Cell Lymphoma via Sponging miR-335-5p

Long-chain non-coding RNAs (LncRNAs) are expressed in diffuse large B-cell lymphoma (DLBCL) tissues and have played a regulatory role in DLBCL with a cancer-promoting effect. In this study, the role of LncRNA SNHG8 in the regulation of DLBCL cells is investigated, and its underlying mechanism is explored. The database of the Gene Expression Profiling Interactive Analysis (GEPIA) was searched, and the expression of SNHG8 in DLBCL and normal tissues was examined. The expression of SNHG8 was evaluated in several DLBCL cell lines and a normal lymphocyte cell line. It was found that SNHG8 was overexpressed in DLBCL tissues and cells in comparison with their normal counterparts. The short hairpin RNA (shRNA) plasmids of SNHG8 were transfected into DLBCL cells to knockdown the expression of SNHG8, followed by assays of proliferation, colony formation, apoptosis, and related protein expression. The results showed that the knockdown of SNHG8 significantly inhibited DLBCL cell proliferation and colony formation while promoting cell apoptosis. Moreover, the knockdown of SNHG8 reduced the expression of Ki-67, proliferating cell nuclear antigen (PCNA), and Bcl-2 and enhanced the expression of Bax and cleaved caspase 3/9. MiR-335-5p was predicted to be a potential target of SNHG8 by using the bioinformatics analysis, and the interaction between the two was validated by using the dual luciferase assay. In addition, the knockdown of SNHG8 increased the level of miR-335-5p, whereas miR-335-5p mimic decreased the expression of SNHG8. Finally, U2932 cells were co-transfected with or without sh-SNHG8 and miR-335-5p inhibitors, whose proliferation, colony formation, and apoptosis were determined subsequently. It was demonstrated that the presence of an miR-335-5p inhibitor partially canceled the inhibitory effects of the knockdown of SNHG8 on DLBCL cell proliferation and colony formation and the stimulating effects of the knockdown of SNHG8 on cell apoptosis. Taken together, our study suggests that lncRNA SNHG8 exerts a cancer-promoting effect on DLBCL via targeting miR-335-5p.