PIK3R1 targeting by miR-21 suppresses tumor cell migration and invasion by reducing PI3K/AKT signaling and reversing EMT, and predicts clinical outcome of breast cancer

MiR-21-5p modulates LPS-induced acute injury in alveolar epithelial cells by targeting SLC16A10

Sepsis is a systemic inflammatory response syndrome resulting from the invasion of the human body by bacteria and other pathogenic microorganisms. One of its most prevalent complications is acute lung injury, which places a significant medical burden on numerous countries and regions due to its high morbidity and mortality rates. MicroRNA (miRNA) plays a critical role in the body's inflammatory response and immune regulation. Recent studies have focused on miR-21-5p in the context of acute lung injury, but its role appears to vary in different models of this condition. In the LPS-induced acute injury model of A549 cells, there is differential expression, but the specific mechanism remains unclear. Therefore, our aim is to investigate the changes in the expression of miR-21-5p and SLC16A10 in a type II alveolar epithelial cell injury model induced by LPS and explore the therapeutic effects of their targeted regulation. A549 cells were directly stimulated with 10 µg/ml of LPS to construct a model of LPS-induced cell injury. Cells were collected at different time points and the expression of interleukin 1 beta (IL-1β), tumor necrosis factor-α (TNF-α) and miR-21-5p were measured by RT-qPCR and western blot. Then miR-21-5p mimic transfection was used to up-regulate the expression of miR-21-5p in A549 cells and the expression of IL-1β and TNF-α in each group of cells was measured by RT-qPCR and western blot. The miRDB, TargetScan, miRWalk, Starbase, Tarbase and miR Tarbase databases were used to predict the miR-21-5p target genes and simultaneously, the DisGeNet database was used to search the sepsis-related gene groups. The intersection of the two groups was taken as the core gene. Luciferase reporter assay further verified SLC16A10 as the core gene with miR-21-5p. The expression of miR-21-5p and SLC16A10 were regulated by transfection or inhibitors in A549 cells with or without LPS stimulation. And then the expression of IL-1β and TNF-α in A549 cells was tested by RT-qPCR and western blot in different groups, clarifying the role of miR-21-5p-SLC16A10 axis in LPS-induced inflammatory injury in A549 cells. (1) IL-1β and TNF-α mRNA and protein expression significantly increased at 6, 12, and 24 h after LPS stimulation as well as the miR-21-5p expression compared with the control group (P < 0.05). (2) After overexpression of miR-21-5p in A549 cells, the expression of IL-1β and TNF-α was significantly reduced after LPS stimulation, suggesting that miR-21-5p has a protection against LPS-induced injury. (3) The core gene set, comprising 51 target genes of miR-21-5p intersecting with the 1448 sepsis-related genes, was identified. This set includes SLC16A10, TNPO1, STAT3, PIK3R1, and FASLG. Following a literature review, SLC16A10 was selected as the ultimate target gene. Dual luciferase assay results confirmed that SLC16A10 is indeed a target gene of miR-21-5p. (4) Knocking down SLC16A10 expression by siRNA significantly reduced the expression of IL-1β and TNF-α in A549 cells after LPS treatment (P < 0.05). (5) miR-21-5p inhibitor increased the expression levels of IL-1β and TNF-α in A549 cells after LPS stimulation (P < 0.05). In comparison to cells solely transfected with miR-21-5p inhibitor, co-transfection of miR-21-5p inhibitor and si-SLC6A10 significantly reduced the expression of IL-1β and TNF-α (P < 0.05). MiR-21-5p plays a protective role in LPS-induced acute inflammatory injury of A549 cells. By targeting SLC16A10, it effectively mitigates the inflammatory response in A549 cells induced by LPS. Furthermore, SLC16A10 holds promise as a potential target for the treatment of acute lung injury.

Role of STAT3 in cancer cell epithelial‑mesenchymal transition (Review)

Since its discovery, the role of the transcription factor, signal transducer and activator of transcription 3 (STAT3), in both normal physiology and the pathology of numerous diseases, including cancer, has been extensively studied. STAT3 is aberrantly activated in different types of cancer, fulfilling a critical role in cancer progression. The biological process, epithelial‑mesenchymal transition (EMT), is indispensable for embryonic morphogenesis. During the development of cancer, EMT is hijacked to confer motility, tumor cell stemness, drug resistance and adaptation to changes in the microenvironment. The aim of the present review was to outline recent advances in knowledge of the role of STAT3 in EMT, which may contribute to the understanding of the function of STAT3 in EMT in various types of cancer. Delineating the underlying mechanisms associated with the STAT3‑EMT signaling axis may generate novel diagnostic and therapeutic options for cancer treatment.

miR-21-5p Modulates Airway Inflammation and Epithelial-Mesenchymal Transition Processes in a Mouse Model of Combined Allergic Rhinitis and Asthma Syndrome

INTRODUCTION

Combined allergic rhinitis and asthma syndrome (CARAS) is a concurrent allergic symptom of diseases of allergic rhinitis and asthma. However, the mechanism of CARAS remains unclear. The study aimed to investigate the impact of microRNA-21 (miR-21) on CARAS via targeting poly (ADP-ribose) polymerase-1 (PARP-1) and phosphoinositide 3-kinase (PI3K)/AKT pathways.

METHODS

The levels of miR-21-5p and PARP-1 in CARAS patients were detected by quantitative reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay (ELISA). An ovalbumin-sensitized mouse model of CARAS was established. And knock down of miR-21-5p was constructed by intranasally administering with miR-21-5p shRNA-encoding adeno-associated virus vector. Airway resistance and airway inflammatory response were detected. ELISA was used to evaluate IL-4/IL-5/IL-13 levels in bronchoalveolar lavage fluid (BALF). Expression levels of E-cadherin, fibronectin, and α-SMA were determined using Western blotting. The levels of PARP-1 and the activation of PI3K/AKT were assayed.

RESULTS

Downregulation of miR-21-5p relieved pathophysiological symptoms of asthma including airway hyperreactivity and inflammatory cell infiltration. Downregulation of miR-21-5p significantly reduced the levels of IL4, IL-5, and IL-13 in BALF. Additionally, downregulation of miR-21-5p inhibited the epithelial-mesenchymal transition (EMT) process in CARAS mice. Furthermore, miR-21-5p regulated PARP-1 and was involved in PI3K/AKT activation in CARAS mice.

CONCLUSION

Downregulation of miR-21-5p ameliorated CARAS-associated lung injury by alleviating airway inflammation, inhibiting the EMT process, and regulating PARP-1/PI3K/AKT in a mouse model of CARAS.

Comparative genomic analysis of PIK3R1-mutated and wild-type breast cancers

PURPOSE

The PIK3R1 gene encodes the regulatory subunit-p85a-of the PI3K signaling complex. Prior studies have found that pathogenic somatic alterations in PIK3R1 are enriched in human breast cancers but the genomic landscape of breast cancer patients harboring PIK3R1 mutations has not been extensively characterized.

METHODS

We retrospectively analyzed 6,009 patient records that underwent next-generation sequencing (NGS) using the Tempus xT solid tumor assay. All patients had breast cancer with known HER2 (+/-) and hormone receptor (HR; +/-) status and were classified according to the presence of PIK3R1 mutations including short variants and copy number alterations.

RESULTS

The frequency of PIK3R1 mutations varied according to subtype: 6% in triple negative (TNBC, 89/1,475), 2% in HER2-/HR+ (80/3,893) and 2.3% in HER2+ (15/641) (p < 0.001). Co-mutations in PTEN, TP53 and NF1 were significantly enriched, co-mutations in PIK3CA were significantly less prevalent, and tumor mutational burden was significantly higher in PIK3R1-mutated HER2- samples relative to PIK3R1 wild-type. At the transcriptional-level, PIK3R1 RNA expression in HER2- disease was significantly higher in PIK3R1-mutated (excluding copy number loss) samples, regardless of subtype.

CONCLUSION

This is the largest investigation of the PIK3R1 mutational landscape in breast cancer patients (n = 6,009). PIK3R1 mutations were more common in triple-negative breast cancer (~ 6%) than in HER2 + or HER2-/HR + disease (approximately 2%). While alterations in the PI3K/AKT pathway are often actionable in HER2-/HR + breast cancer, our study suggests that PIK3R1 could be an important target in TNBC as well.

Inhibition of Mir-21-5p Affects the Expression of LNCRNA X-Inactive Specific Transcript and Induces Apoptosis in MCF-7 Breast Cancer Cells

Background

We aimed to investigate miR-21-5p inhibition effect on lncRNA-XIST expression and apoptosis status of MCF-7 cells.

Methods

The MCF-7 cells were cultured and transfected by the anti-miR-21-5p oligonucleotide and expression of miR-21-5p, lncRNA-XIST, apoptosis-associated genes (bax and p53) and one miR-21-5p-unrelated lncRNA (BC200) was assessed by RT-qPCR. Furthermore, cell viability checked by MTT assay and apoptosis and cell cycle in transfected cells were detected by flow cytometry. Also, bioinformatics analysis on the transcriptome data confirmed that the lncRNA XIST might have a critical role in breast cancer (BC) cell apoptosis through ceRNAs mechanism and possible regulatory interactions with miR-21-5p.

Results

Expression of miR-21-5p and lncRNA-XIST was significantly down- and up-regulated respectively (P<0.05). However, there was no significant change in lncRNA-BC200 expression. Also, the expression of bax and p53 upraised significantly (P<0.05). In transfected cells, MTT and flow cytometry assays reported a highly significant decrease and increase in viability and apoptosis respectively.

Conclusion

Inhibition of miR-21-5p resulted in significant upregulation of lncRNA-XIST and apoptosis-associated genes bax and p53, which led to the induction of apoptosis in MCF-7 cells. Therefore, more investigations may provide a valuable target for studies on molecular therapies for BC.

Unraveling the Potential of miRNAs from CSCs as an Emerging Clinical Tool for Breast Cancer Diagnosis and Prognosis

Breast cancer (BC) is the most diagnosed cancer in women and the second most common cancer globally. Significant advances in BC research have led to improved early detection and effective therapies. One of the key challenges in BC is the presence of BC stem cells (BCSCs). This small subpopulation within the tumor possesses unique characteristics, including tumor-initiating capabilities, contributes to treatment resistance, and plays a role in cancer recurrence and metastasis. In recent years, microRNAs (miRNAs) have emerged as potential regulators of BCSCs, which can modulate gene expression and influence cellular processes like BCSCs' self-renewal, differentiation, and tumor-promoting pathways. Understanding the miRNA signatures of BCSCs holds great promise for improving BC diagnosis and prognosis. By targeting BCSCs and their associated miRNAs, researchers aim to develop more effective and personalized treatment strategies that may offer better outcomes for BC patients, minimizing tumor recurrence and metastasis. In conclusion, the investigation of miRNAs as regulators of BCSCs opens new directions for advancing BC research through the use of bioinformatics and the development of innovative therapeutic approaches. This review summarizes the most recent and innovative studies and clinical trials on the role of BCSCs miRNAs as potential tools for early diagnosis, prognosis, and resistance.

MicroRNAs: The key players regulating the crosstalk between Hippo and Wnt/β-catenin pathways in breast cancer

Breast Cancer has the highest burden in females worldwide and is predicted to increase by many folds with increasing lifestyle related risk factors, genetic mutations, and an aging population. The Hippo signalling and Wnt signalling pathways were identified as important signal transducers involved in maintaining organ development, tissue homeostasis, cell proliferation and apoptosis. microRNAs are short nucleotide sequences which act as regulatory components driving signal transductions in most cancers and can serve as both diagnostic and prognostic markers. Several reports have implicated that deregulated Hippo as well as Wnt signalling mediated by miRNAs together drive tumorigenesis, metastases and chemoresistance in breast cancer. Recent evidences on a crosstalk between Hippo and Wnt components elucidated how these pathways might be synchronized to have overlapping functions to promote tumorigenesis. Since miRNAs are demonstrated to target most of the components in both the pathways, in this review, we talk about the crosstalk between Hippo and Wnt signalling pathways and the potential microRNAs that might regulate the interplay between the two pathways in breast cancer, which has not been explored earlier.

Omics data analysis reveals common molecular basis of small cell lung cancer and COVID-19

The impact of COVID-19 infection on individuals with small cell lung cancer (SCLC) poses a serious threat. Unfortunately, the molecular basis of this severe comorbidity has yet to be elucidated. The present study addresses this gap utilizing publicly available omics data of COVID-19 and SCLC to explore the key molecules and associated pathways involved in the convergence of these diseases. Findings revealed 402 genes, that exhibited differential expression patterns in SCLC patients and also play a pivotal role in COVID-19 pathogenesis. Subsequent functional enrichment analyses identified relevant ontologies and pathways that are significantly associated with these genes, revealing important insights into their potential biological, molecular and cellular functions. The protein-protein interaction network, constructed under four combinatorial topological assessments, highlighted SMAD3, CAV1, PIK3R1, and FN1 as the primary components to this comorbidity. Our results suggest that these components significantly regulate this cross-talk triggering the PI3K-AKT and TGF-β signaling pathways. Lastly, this study made a multi-step computational attempt and identified corylifol A and ginkgetin from natural sources that can potentially inhibit these components. Therefore, the outcomes of this study offer novel perspectives on the common molecular mechanisms underlying SCLC and COVID-19 and present future opportunities for drug development.Communicated by Ramaswamy H. Sarma.

AUTOSURV: INTERPRETABLE DEEP LEARNING FRAMEWORK FOR CANCER SURVIVAL ANALYSIS INCORPORATING CLINICAL AND MULTI-OMICS DATA

Accurate prognosis for cancer patients can provide critical information for optimizing treatment plans and improving life quality. Combining omics data and demographic/clinical information can offer a more comprehensive view of cancer prognosis than using omics or clinical data alone and can reveal the underlying disease mechanisms at the molecular level. In this study, we developed a novel deep learning framework to extract information from high-dimensional gene expression and miRNA expression data and conduct prognosis prediction for breast cancer and ovarian cancer patients. Our model achieved significantly better prognosis prediction than the conventional Cox Proportional Hazard model and other competitive deep learning approaches in various settings. Moreover, an interpretation approach was applied to tackle the "black-box" nature of deep neural networks and we identified features (i.e., genes, miRNA, demographic/clinical variables) that made important contributions to distinguishing predicted high- and low-risk patients. The identified associations were partially supported by previous studies.

miR-21 Targets ASPP2 to Inhibit Apoptosis via CHOP-Mediated Signaling in Helicobacter pylori-Infected Gastric Cancer Cells

Helicobacter pylori (H. pylori) infection affects cell survival pathways, including apoptosis and proliferation in host cells, and disruption of this balance is the key event in the development of H. pylori-induced gastric cancer (HPGC). H. pylori infection induces alterations in microRNAs expression that may be involved in GC development. Bioinformatic analysis showed that microRNA-21 (miR-21) is significantly upregulated in HPGC. Furthermore, quantitative proteomics and in silico prediction were employed to identify potential targets of miR-21. Following functional enrichment and clustered interaction network analyses, five candidates of miR-21 targets, PDCD4, ASPP2, DAXX, PIK3R1, and MAP3K1, were found across three functional clusters in association with cell death and survival, cellular movement, and cellular growth and proliferation. ASPP2 is inhibited by H. pylori-induced miR-21 overexpression. Moreover, ASPP2 levels are inversely correlated with miR-21 levels in HPGC tumor tissues. Thus, ASPP2 was identified as a miR-21 target in HPGC. Here, we observed that H. pylori-induced ASPP2 suppression enhances resistance to apoptosis in GC cells using apoptosis assays. Using protein interaction network and coimmunoprecipitation assay, we identified CHOP as a direct mediator of the ASPP2 proapoptotic activity in H. pylori-infected GC cells. Mechanistically, ASPP2 suppression promotes p300-mediated CHOP degradation, in turn inhibiting CHOP-mediated transcription of Noxa, Bak, and suppression of Bcl-2 to enact antiapoptosis in the GC cells after H. pylori infection. Clinicopathological analysis revealed correlations between decreased ASPP2 expression and higher HPGC risk and poor prognosis. In summary, the discovery of H. pylori-induced antiapoptosis via miR-21-mediated suppression of ASPP2/CHOP-mediated signaling provides a novel perspective for developing HPGC management and treatment.

Identification and comprehensive analysis of epithelial-mesenchymal transition related target genes of miR-222-3p in breast cancer

Background

Epithelial-mesenchymal transition (EMT) is a crucial mechanism that microRNA-222-3p (miR-222-3p) promotes breast cancer (BC) progression. Our study aimed to identify EMT-associated target genes (ETGs) of miR-222-3p for further analysis of their roles in BC based on bioinformatics tools.

Methods

Based on bioinformatics analysis, we identified 10 core ETGs of miR-222-3p. Then, we performed a comprehensive analysis of 10 ETGs and miR-222-3p, including pathway enrichment analysis of ETGs, differential expression, clinical significance, correlation with immune cell infiltration, immune checkpoint genes (ICGs) expression, tumor mutational burden (TMB), microsatellite instability (MSI), stemness, drug sensitivity, and genetic alteration.

Results

The expression of miR222-3p in basal-like BC was significantly higher than in other subtypes of BC and the normal adjacent tissue. Pathway analysis suggested that the ETGs might regulate the EMT process via the PI3K-Akt and HIF-1 signaling pathway. Six of the 10 core ETGs of miR-222-3p identified were down-expressed in BC, which were EGFR, IL6, NRP1, NTRK2, LAMC2, and PIK3R1, and SERPINE1, MUC1, MMP11, and BIRC5 were up-expressed in BC, which also showed potential diagnostic values in BC. Prognosis analysis revealed that higher NTRK2 and PIK3R1 expressions were related to a better prognosis, and higher BIRC5 and miR-222-3p expressions were related to a worse prognosis. Most ETGs and miR-222-3p were positively correlated with various infiltration of various immune cells and ICGs expression. Lower TMB scores were correlated with higher expression of MUC1 and NTRK2, and higher BIRC5 was related to a higher TMB score. Lower expression of MUC1, NTRK2, and PIK3R1 were associated with higher MSI scores. Higher expression of ETGs was associated with lower mRNAsi scores, except BIRC5 and miR-222-3p conversely. Most ETGs and miR-222-3p expression were negatively correlated with the drug IC50 values. The analysis of the genetic alteration of the ETGs suggested that amplification was the main genetic alteration of eight ETGs except for NTRK2 and PIK3R1.

Conclusion

MiR-222-3p might be a specific biomarker of basal-like BC. We successfully identify 10 core ETGs of miR-222-3p, some might be useful diagnostic and prognostic biomarkers. The comprehensive analysis of 10 ETGs and miR-222-3p indicated that they might be involved in the development of BC, which might be novel therapeutic targets for the treatment of BC.

Investigation of miR-133a, miR-637 and miR-944 genes expression and their relationship with PI3K/AKT signaling in women with breast cancer

PURPOSE

MicroRNAs (miRNAs) are regulatory molecules capable of positively or negatively regulating signaling pathways, and are involved in tumorigenesis as well as various aspects of cancer. The purpose of this study was to investigate the expression levels of miR-133a, miR-637, and miR-944 in serum and tumor tissues as well as their relationship with the expression level of phosphatidylinositol-3-kinase (PI3K) and protein kinase-B (AKT) genes and proteins along with their clinical significance in breast cancer.

METHODS

The expressions of miR-133a, miR-637, miR-944, PI3K, and AKT genes were examined in the tumor and tumor margin tissues of 40 patients with breast cancer, as well as the serum levels of miR-133a, miR-637, and miR-944 in these patients and 40 healthy groups by quantitative real-time PCR (qRT-PCR). PI3K and AKT proteins expression in tumor and tumor margin tissues were detected using immunohistochemistry (IHC).

RESULTS

The expression levels of miR-133a and miR-637 in the tumor tissue and serum of patients were lower than those in the tumor margin tissue and serum of the healthy group, respectively. In addition, the expression level of miR-944 in the tumor tissue was lower than that in the tumor margin tissue, but its expression increased in the serum of cancer patients compared to that in the healthy group. The expression of miR-637 was correlated with tumor location and Her2 receptors, and the expression of miR-944 was correlated with tumor location and family history. PI3K and AKT mRNA and protein levels were higher in the tumor tissues than in the tumor margin tissues (p < 0.05).

CONCLUSION

The results of our study revealed that miR-637 has a better diagnostic value in breast cancer than miR-133a and miR-944.

Identification of Key Biomarkers and Candidate Molecules in Non-Small-Cell Lung Cancer by Integrated Bioinformatics Analysis

Background

Non-small cell lung cancer (NSCLC) is the most prevalent malignant tumor of the lung cancer, for which the molecular mechanisms remain unknown. In this study, we identified novel biomarkers associated with the pathogenesis of NSCLC aiming to provide new diagnostic and therapeutic approaches for NSCLC by bioinformatics analysis.

Methods

From the Gene Expression Omnibus database, GSE118370 and GSE10072 microarray datasets were obtained. Identifying the differentially expressed genes (DEGs) between lung adenocarcinoma and normal samples was done. By using bioinformatics tools, a protein-protein interaction (PPI) network was constructed, modules were analyzed, and enrichment analyses were performed. The expression and prognostic values of 14 hub genes were validated by the GEPIA database, and the correlation between hub genes and survival in lung adenocarcinoma was assessed by UALCAN, cBioPortal, String and Cytoscape, and Timer tools.

Results

We found three genes (PIK3R1, SPP1, and PECAM1) that have a clear correlation with OS in the lung adenocarcinoma patient. It has been found that lung adenocarcinoma exhibits high expression of SPP1 and that this has been associated with poor prognosis, while low expression of PECAM1 and PIK3R1 is associated with poor prognosis (P < 0.05). We also found that the expression of SPP1 was associated with miR-146a-5p, while the high expression of miR-146a-5p was related to good prognosis (P < 0.05). On the contrary, the lower miR-21-5p on upstream of PIK3R1 is associated with a higher surviving rate in cancer patients (P < 0.05). Finally, we found that the immune checkpoint genes CD274(PD-L1) and PDCD1LG2(PD-1) were also related to SPP1 in lung adenocarcinoma.

Conclusions

The results indicated that SPP1 is a cancer promoter (oncogene), while PECAM1 and PIK3R1 are cancer suppressor genes. These genes take part in the regulation of biological activities in lung adenocarcinoma, which provides a basis for improving detection and immunotherapeutic targets for lung adenocarcinoma.

Pre-clinical and clinical importance of miR-21 in human cancers: Tumorigenesis, therapy response, delivery approaches and targeting agents

The field of non-coding RNA (ncRNA) has made significant progress in understanding the pathogenesis of diseases and has broadened our knowledge towards their targeting, especially in cancer therapy. ncRNAs are a large family of RNAs with microRNAs (miRNAs) being one kind of endogenous RNA which lack encoded proteins. By now, miRNAs have been well-coined in pathogenesis and development of cancer. The current review focuses on the role of miR-21 in cancers and its association with tumor progression. miR-21 has both oncogenic and onco-suppressor functions and most of the experiments are in agreement with the tumor-promoting function of this miRNA. miR-21 primarily decreases PTEN expression to induce PI3K/Akt signaling in cancer progression. Overexpression of miR-21 inhibits apoptosis and is vital for inducing pro-survival autophagy. miR-21 is vital for metabolic reprogramming and can induce glycolysis to enhance tumor progression. miR-21 stimulates EMT mechanisms and increases expression of MMP-2 and MMP-9 thereby elevating tumor metastasis. miR-21 is a target of anti-cancer agents such as curcumin and curcumol and its down-regulation impairs tumor progression. Upregulation of miR-21 results in cancer resistance to chemotherapy and radiotherapy. Increasing evidence has revealed the role of miR-21 as a biomarker as it is present in both the serum and exosomes making them beneficial biomarkers for non-invasive diagnosis of cancer.

Adipose Rheb deficiency promotes miR-182-5p expression via the cAMP/PPARγ signaling pathway

Dysregulation of microRNAs (miRNAs) in adipocytes plays a critical role in the pathogenesis of obesity. However, the signaling mechanisms regulating miRNAs production in adipose tissue remain largely unclear. Here, we show that adipose tissue-specific knockout of Ras homolog enriched in brain (Rheb), a direct upstream activator of mTOR, increases miR-182-5p level in mouse subcutaneous white adipose tissues. Interestingly, the inhibition of mTOR signaling by rapamycin has no effect on miR-182-5p level in primary subcutaneous white adipocytes, suggesting the presence of a mTOR-independent mechanism regulating Rheb-mediated miR-182-5p expression. Consistent with this view, Rheb-ablation activates the cAMP/PPARγ signaling pathway. In addition, treatment of white adipocytes with pioglitazone, a PPARγ agonist, dramatically upregulates miR-182-5p levels. Our study reveals a unique mechanism by which Rheb regulates miR-182-5p in adipocytes. Given that increasing miR-182-5p in adipose tissue promotes beige fat development, our study also suggests a unique mechanism by which Rheb promotes thermogenesis and energy expenditure.

Screening and analysis of key genes in the biological behavior of bone mesenchymal stem cells seeded on gradient nanostructured titanium compared with native pure Ti

Titanium (Ti) and Ti-based alloy materials are ideal brackets that restore bone defect, and the mechanism of related genes inducing bone mesenchymal stem cells (BMSCs) to osteogenic differentiation is currently a hot research topic. In order to screen key genes of BMSCs during the osteogenic expression process, we acquired data sets (GSE37237 and GSE84500) which were in the database Gene Expression Omnibus (GEO). Investigations on differentially expressed genes (DEGs) and their enrichment of functions were conducted. We constructed relative protein-protein interaction (PPI) network by using Search Tool for the Retrieval of Interacting Genes (STRING) and visualized the expression of DEGs with Cytoscape. A total of 279 DEGs were discerned, which could be divided into 177 down regulated genes and 102 up regulated genes. In addition, the DEGs' enrichment and pathways included regulation of actin cytoskeleton, inflammatory mediator regulation of transient receptor potential (TRP) channels, peroxisome proliferator-activated receptors (PPAR) pathway, cell cycle, Rheumatoid arthritis, mitogen-activated protein kinases (MAPK) signaling pathway and Ras signaling pathway ect. It showed that 10 notable up regulated genes were mainly in AMP-activated protein kinase (AMPK) pathway. Then we used a technology named surface mechanical attrition treatment (SMAT) to prepare gradient nanostructured (GNS) surface Ti and seeded well-growing BMSCs on the surface of SMAT Ti and native pure Ti. Cell Counting Kits-8 (CCK-8), apoptosis experiment, immunofluorescence technology and staining experiments for alka-line phosphatase (ALP) and alizarin red staining (ARS) were used to research the proliferation, adhesion and differentiation ability of BMSCs seeded on SMAT Ti compared with native pure Ti. We used quantitative real-time PCR (qRT-PCR) technology so as to verify the expression of the most significant 5 genes. In summary, these results indicated novel point of views into candidate genes and potential mechanism for the further study of BMSCs' behaviors seeded on SMAT Ti.

miR-21 Regulates the Growth of Gastric Cancer Cells Through Targeting Phosphatase and Tensin Homolog (PTEN)

Gastric cancer (GC) is the leading cause of death worldwide and the prognosis remains poor. Proliferation and apoptosis of cancer cells are regulated by microRNAs (miRNAs). We herein intended to explore the interaction of miR-21 and PTEN in GC. miR-21 inhibitor or negative control was transfected into GC cells MGC-803 followed by analysis of miR-21 and PTEN level by RT-qPCR, PTEN protein level by western blot and cell growth by MTT and Hoechest-33342 staining. Treatment with miR-21 inhibitor reduced miR-21 expression and increased PTEN protein expression. miR-21 was negatively associated with PTEN level. Moreover, downregulation of miR-21 decreased cell proliferation and promoted apoptosis. In conclusion, miR-21 stimulates the malignant phenotypes of GC cells by negatively regulating PTEN expression, providing novel insight into the pathogenesis of gastric cancer.

MicroRNA-503 Exacerbates Myocardial Ischemia/Reperfusion Injury via Inhibiting PI3K/Akt- and STAT3-Dependent Prosurvival Signaling Pathways

Acute myocardial infarction is a leading cause of death worldwide, while restoration of blood flow to previously ischemic myocardium may lead to ischemia/reperfusion (I/R) injury. Accumulated evidence shows that microRNAs play important roles in cardiovascular diseases. However, the potential role of microRNA-503 (miR-503) in myocardial I/R injury is little known. Thus, this study is aimed at determining whether and how miR-503 affects myocardial I/R injury in vivo and in vitro. A mouse model of myocardial I/R injury and H9c2 cell model of hypoxia/reoxygenation (H/R) injury were established. The postischemic cardiac miR-503 was downregulated in vivo and in vitro. Mechanistically, PI3K p85 and Bcl-2 are miR-503 targets. The post-ischemic cardiac PI3K p85 protein level was decreased in vivo. Agomir-503 treatment exacerbated H/R-induced injuries manifested as decreased cell viability, increased lactate dehydrogenase activity, and cell apoptosis. Agomir-503 treatment reduced cell viability under normoxia as well and reduced both PI3K p85 and Bcl-2 protein levels under either normoxia or H/R condition. It reduced phosphorylation of Stat3 (p-Stat3-Y705) and Akt (T450) in cells subjected to H/R. In contrast, Antagomir-503 treatment attenuated H/R injury and increased p-Stat3 (Y705) under normoxia and increased p-Akt (T450) under either normoxia or H/R condition. It is concluded that miR-503 exacerbated I/R injury via inactivation of PI3K/Akt and STAT3 pathways and may become a therapeutic target in preventing myocardial I/R injury.

Identification and Validation of Dilated Cardiomyopathy-Related Genes via Bioinformatics Analysis

Purpose

Dilated cardiomyopathy (DCM) is a type of cardiomyopathy that can easily cause heart failure and has a high mortality rate. Therefore, there is an urgent need to study the underlying mechanism of action of dilated cardiomyopathy. In the present study, we aimed to explore potential miRNA–mRNA pairs and drugs related to DCM.

Methods

The Microarray data were collected from the Gene Expression Omnibus (GEO) database. Bioinformatics analysis differentially expressed miRNAs and mRNAs in each microarray were obtained. The target genes of miRNAs were obtained from the miRWalk 2.0 database, and the intersection of these two gene sets (miRNA target genes and differentially expressed mRNAs in the microarray) was obtained. Pathway and Gene Ontology (GO) enrichment analyses were performed in the KOBAS database. Cytoscape software was used to construct the miRNA–mRNA network, and the final hub genes were obtained. Furthermore, we predicted several candidate drugs related to hub genes using DSigDB database. To confirm the abnormal expression of hub genes, qRT-PCR was performed.

Results

In total, eight differentially expressed miRNAs and 92 differentially expressed mRNAs were identified. In addition, 47 differentially expressed miRNA target genes were identified. According to the analysis results of the miRNA-mRNA network, we identified hsa-miR-551b-3p, hsa-miR-770-5p, hsa-miR-363-3p, PIK3R1, DDIT4, and CXCR4 as hub genes in DCM. Several candidate drugs, which are related to the hug genes, were identified.

Conclusion

In conclusion, in our study, we identified several hub genes that may be involved in the pathogenesis of DCM. Several drugs related to these hub genes may be used as clinical therapeutic candidates.

microRNAs in the pathogenesis of non-obstructive azoospermia: the underlying mechanisms and therapeutic potentials

miRNAs are involved in different biological processes, including proliferation, differentiation, and apoptosis. Interestingly, 38% of the X chromosome-linked miRNAs are testis-specific and have crucial roles in regulating the renewal and cell cycle of spermatogonial stem cells. Previous studies demonstrated that abnormal expression of spermatogenesis-related miRNAs could lead to nonobstructive azoospermia (NOA). Moreover, differential miRNAs expression in seminal plasma of NOA patients has been reported compared to normozoospermic men. However, the role of miRNAs in NOA pathogenesis and the underlying mechanisms have not been comprehensively studied. Therefore, the aim of this review is to mechanistically describe the role of miRNAs in the pathogenesis of NOA and discuss the possibility of using the miRNAs as therapeutic targets.Abbreviations: AMO: anti-miRNA antisense oligonucleotide; AZF: azoospermia factor region; CDK: cyclin-dependent kinase; DAZ: deleted in azoospermia; ESCs: embryonic stem cells; FSH: follicle-stimulating hormone; ICSI: intracytoplasmic sperm injection; JAK/STAT: Janus kinase/signal transducers and activators of transcription; miRNA: micro-RNA; MLH1: Human mutL homolog l; NF-κB: Nuclear factor-kappa B; NOA: nonobstructive azoospermia; OA: obstructive azoospermia; PGCs: primordial germ cells; PI3K/AKT: Phosphatidylinositol 3-kinase/protein kinase B; Rb: retinoblastoma tumor suppressor; ROS: Reactive Oxygen Species; SCOS: Sertoli cell-only syndrome; SIRT: sirtuin; SNPs: single nucleotide polymorphisms; SSCs: spermatogonial stem cells; TESE: testicular sperm extraction; TGF-β: transforming growth factor-beta.

The regulatory role of pivotal microRNAs in the AKT signaling pathway in breast cancer

Breast cancer is the most prevalent type of cancer among women, and it remains the main challenge despite improved treatments. MicroRNAs (miRNAs) are a small non-coding family of RNAs that play an indispensable role in regulating major physiological processes, including differentiation, proliferation, invasion, migration, cell cycle regulation, stem cell maintenance, apoptosis, and organ development. The dysregulation of these tiny molecules is associated with various human malignancies. More than 50% of these non-coding RNA sequences estimated have been placed on genomic regions or fragile sites linked to cancer. Following the discovery of the first signatures of specific miRNA in breast cancer, numerous researches focused on involving these tiny RNAs in breast cancer physiopathology as a new therapeutic approach or as reliable prognostic biomarkers. In the current review, we focus on recent findings related to the involvement of miRNAs in breast cancer via the AKT signaling pathway and the related clinical implications.

miR-92a promotes cervical cancer cell proliferation, invasion, and migration by directly targeting PIK3R1

OBJECTIVE

To clarify the role of miR-92a in regulating the malignant progression of cervical cancer and its specific molecular mechanism.

METHODS

qRT-PCR was used to detect the differential expression of miR-92a in cervical cancer and adjacent tissues. The effects of overexpression of miR-92a on the proliferation, migration, and invasion of HeLa and SiHa cells were tested. Luciferase assays and rescue experiments were used to investigate the regulatory mechanism of miR-92a on its downstream gene PIK3R1 and their interaction in the progression of cervical cancer.

RESULTS

miR-92a was significantly up-regulated in cervical cancer tissues. Overexpression of miR-92a significantly increased the ability of cervical cancer cells to proliferate, migrate, and invade. PIK3R1 was identified as a downstream gene of miR-92a. In cervical cancer tissues, PIK3R1 was found to be down-regulated and negatively correlated with the level of miR-92a. Overexpression of PIK3R1 reversed the promotional effect of overexpressed miR-92a on the proliferation, migration, and invasion of cervical cancer.

CONCLUSION

miR-92a is up-regulated in cervical cancer tissues. miR-92a promotes the malignant development of cervical cancer by negatively regulating PIK3R1.

MicroRNAs: The Link between the Metabolic Syndrome and Oncogenesis

Metabolic syndrome (MetS) represents a cluster of disorders that increase the risk of a plethora of conditions, in particular type two diabetes, cardiovascular diseases, and certain types of cancers. MetS is a complex entity characterized by a chronic inflammatory state that implies dysregulations of adipokins and proinflammatory cytokins together with hormonal and growth factors imbalances. Of great interest is the implication of microRNA (miRNA, miR), non-coding RNA, in cancer genesis, progression, and metastasis. The adipose tissue serves as an important source of miRs, which represent a novel class of adipokines, that play a crucial role in carcinogenesis. Altered miRs secretion in the adipose tissue, in the context of MetS, might explain their implication in the oncogenesis. The interplay between miRs expressed in adipose tissue, their dysregulation and cancer pathogenesis are still intriguing, taking into consideration the fact that miRNAs show both carcinogenic and tumor suppressor effects. The aim of our review was to discuss the latest publications concerning the implication of miRs dysregulation in MetS and their significance in tumoral signaling pathways. Furthermore, we emphasized the role of miRNAs as potential target therapies and their implication in cancer progression and metastasis.

Hypoxia regulates human mast cell adhesion to fibronectin via the PI3K/AKT signaling pathway

A decrease in oxygen concentration is a hallmark of inflammatory reactions resulting from infection or homeostasis disorders. Mast cells interact with extracellular matrix and other cells by adhesion receptors. We investigated the effect of hypoxia on integrin-mediated mast cell adhesion to fibronectin. We found that it was mediated by the α5/β1 receptor and that hypoxia significantly upregulated this process. Hypoxia-mediated increases in mast cell adhesion occurred without increased surface expression of integrins, suggesting regulation by inside-out integrin signaling. Hypoxia also mediated an increase in phosphorylation of Akt, and PI3’kinase inhibitors abolished hypoxia-mediated mast cell adhesion. Hypoxia upregulates the function of integrin receptors by PI3’ kinase-dependent signaling. This process might be important for the location of mast cells at inflammatory sites

Deciphering molecular mechanisms of metastasis: novel insights into targets and therapeutics

BACKGROUND

The transition of a primary tumour to metastatic progression is driven by dynamic molecular changes, including genetic and epigenetic alterations. The metastatic cascade involves bidirectional interactions among extracellular and intracellular components leading to disintegration of cellular junctions, cytoskeleton reorganization and epithelial to mesenchymal transition. These events promote metastasis by reprogramming the primary cancer cell's molecular framework, enabling them to cause local invasion, anchorage-independent survival, cell death and immune resistance, extravasation and colonization of distant organs. Metastasis follows a site-specific pattern that is still poorly understood at the molecular level. Although various drugs have been tested clinically across different metastatic cancer types, it has remained difficult to develop efficacious therapeutics due to complex molecular layers involved in metastasis as well as experimental limitations.

CONCLUSIONS

In this review, a systemic evaluation of the molecular mechanisms of metastasis is outlined and the potential molecular components and their status as therapeutic targets and the associated pre-clinical and clinical agents available or under investigations are discussed. Integrative methods like pan-cancer data analysis, which can provide clinical insights into both targets and treatment decisions and help in the identification of crucial components driving metastasis such as mutational profiles, gene signatures, associated pathways, site specificities and disease-gene phenotypes, are discussed. A multi-level data integration of the metastasis signatures across multiple primary and metastatic cancer types may facilitate the development of precision medicine and open up new opportunities for future therapies.

MicroRNA Regulation of Breast Cancer Stemness

Recent advances in our understanding of breast cancer have demonstrated that cancer stem-like cells (CSCs, also known as tumor-initiating cell (TICs)) are central for progression and recurrence. CSCs are a small subpopulation of cells present in breast tumors that contribute to growth, metastasis, therapy resistance, and recurrence, leading to poor clinical outcome. Data have shown that cancer cells can gain characteristics of CSCs, or stemness, through alterations in key signaling pathways. The dysregulation of miRNA expression and signaling have been well-documented in cancer, and recent studies have shown that miRNAs are associated with breast cancer initiation, progression, and recurrence through regulating CSC characteristics. More specifically, miRNAs directly target central signaling nodes within pathways that can drive the formation, maintenance, and even inhibition of the CSC population. This review aims to summarize these research findings specifically in the context of breast cancer. This review also discusses miRNAs as biomarkers and promising clinical therapeutics, and presents a comprehensive summary of currently validated targets involved in CSC-specific signaling pathways in breast cancer.

Cancer-Associated Stemness and Epithelial-to-Mesenchymal Transition Signatures Related to Breast Invasive Carcinoma Prognostic

Simple Summary

Breast cancer is one of the most common oncological diseases in women, as its incidence is rapidly growing. In this study, we have investigated the mechanism of epithelial-to-mesenchymal transition (EMT) and cancer stem cells (CSCs), demonstrating presence of an interconnectedness between them. This interconnectedness plays important roles in patient prognostic, as well as in diagnostic and therapeutic targets. It is identified that there is a common signature between CSCs and EMT, and this is represented by ALDH1A1, SFRP1, miR-139, miR-21, and miR-200c. This finding will provide a better understanding of this mechanism, and will facilitate the development of novel treatment options.

Abstract

Breast cancer is one of the most common oncological diseases in women, as its incidence is rapidly growing, rendering it unpredictable and causing more harm than ever before on an annual basis. Alterations of coding and noncoding genes are related to tumorigenesis and breast cancer progression. In this study, several key genes associated with epithelial-to-mesenchymal transition (EMT) and cancer stem cell (CSC) features were identified. EMT and CSCs are two key mechanisms responsible for self-renewal, differentiation, and self-protection, thus contributing to drug resistance. Therefore, understanding of the relationship between these processes may identify a therapeutic vulnerability that can be further exploited in clinical practice, and evaluate its correlation with overall survival rate. To determine expression levels of altered coding and noncoding genes, The Cancer Omics Atlas (TCOA) are used, and these data are overlapped with a list of CSCs and EMT-specific genes downloaded from NCBI. As a result, it is observed that CSCs are reciprocally related to EMT, thus identifying common signatures that allow for predicting the overall survival for breast cancer genes (BRCA). In fact, common CSCs and EMT signatures, represented by ALDH1A1, SFRP1, miR-139, miR-21, and miR-200c, are deemed useful as prognostic biomarkers for BRCA. Therefore, by mapping changes in gene expression across CSCs and EMT, suggesting a cross-talk between these two processes, we have been able to identify either the most common or specific genes or miRNA markers associated with overall survival rate. Thus, a better understanding of these mechanisms will lead to more effective treatment options.

Investigating potential molecular mechanisms of serum exosomal miRNAs in colorectal cancer based on bioinformatics analysis

Colorectal cancer (CRC) is the most common malignant gastrointestinal tumor worldwide. Serum exosomal microRNAs (miRNAs) play a critical role in tumor progression and metastasis. However, the underlying molecular mechanisms are poorly understood.The miRNAs expression profile (GSE39833) was downloaded from Gene Expression Omnibus (GEO) database. GEO2R was applied to screen the differentially expressed miRNAs (DEmiRNAs) between healthy and CRC serum exosome samples. The target genes of DEmiRNAs were predicted by starBase v3.0 online tool. The gene ontology (GO) and Kyoto Encyclopedia of Genomes pathway (KEGG) enrichment analysis were performed using the Database for Annotation, Visualization and Integrated Discovery (DAVID) online tool. The protein-protein interaction (PPI) network was established by the Search Tool for the Retrieval of Interacting Genes (STRING) visualized using Cytoscape software. Molecular Complex Detection (MCODE) and cytohubba plug-in were used to screen hub genes and gene modules.In total, 102 DEmiRNAs were identified including 67 upregulated and 35 downregulated DEmiRNAs, and 1437 target genes were predicted. GO analysis showed target genes of upregulated DEmiRNAs were significantly enriched in transcription regulation, protein binding, and ubiquitin protein ligase activity. While the target genes of downregulated DEmiRNAs were mainly involved in transcription from RNA polymerase II promoter, SMAD binding, and DNA binding. The KEGG pathway enrichment analyses showed target genes of upregulated DEmiRNAs were significantly enriched in proteoglycans in cancer, microRNAs in cancer, and phosphatidylinositol-3 kinases/Akt (PI3K-Akt) signaling pathway, while target genes of downregulated DEmiRNAs were mainly enriched in transforming growth factor-beta (TGF-beta) signaling pathway and proteoglycans in cancer. The genes of the top 3 modules were mainly enriched in ubiquitin mediated proteolysis, spliceosome, and mRNA surveillance pathway. According to the cytohubba plugin, 37 hub genes were selected, and 4 hub genes including phosphoinositide-3-kinase regulatory subunit 1 (PIK3R1), SRC, cell division cycle 42 (CDC42), E1A binding protein p300 (EP300) were identified by combining 8 ranked methods of cytohubba.The study provides a comprehensive analysis of exosomal DEmiRNAs and target genes regulatory network in CRC, which can better understand the roles of exosomal miRNAs in the development of CRC. However, these findings require further experimental validation in future studies.

Establishment of a novel cell cycle-related prognostic signature predicting prognosis in patients with endometrial cancer

Background

Endometrial cancer (EnCa) ranks fourth in menace within women’s malignant tumors. Large numbers of studies have proven that functional genes can change the process of tumors by regulating the cell cycle, thereby achieving the goal of targeted therapy.

Methods

The transcriptional data of EnCa samples obtained from the TCGA database was analyzed. A battery of bioinformatics strategies, which included GSEA, Cox and LASSO regression analysis, establishment of a prognostic signature and a nomogram for overall survival (OS) assessment. The GEPIA and CPTAC analysis were applied to validate the dysregulation of hub genes. For mutation analysis, the “maftools” package was used.

Results

GSEA identified that cell cycle was the most associated pathway to EnCa. Five cell cycle-related genes including HMGB3, EZH2, NOTCH2, UCK2 and ODF2 were identified as prognosis-related genes to build a prognostic signature. Based on this model, the EnCa patients could be divided into low- and high-risk groups, and patients with high-risk score exhibited poorer OS. Time-dependent ROC and Cox regression analyses revealed that the 5-gene signature could predict EnCa prognosis exactly and independently. GEPIA and CPTAC validation exhibited that these genes were notably dysregulated between EnCa and normal tissues. Lower mutation rates of PTEN, TTN, ARID1A, and etc. were found in samples with high-risk score compared with that with low-risk score. GSEA analysis suggested that the samples of the low- and high-risk groups were concentrated on various pathways, which accounted for the different oncogenic mechanisms in patients in two groups.

Conclusion

The current research construct a 5-gene signature to evaluate prognosis of EnCa patients, which may innovative clinical application of prognostic assessment.

Potential miRNAs for miRNA-Based Therapeutics in Breast Cancer

MicroRNAs (miRNAs) are small non-coding RNAs that can post-transcriptionally regulate the genes involved in critical cellular processes. The aberrant expressions of oncogenic or tumor suppressor miRNAs have been associated with cancer progression and malignancies. This resulted in the dysregulation of signaling pathways involved in cell proliferation, apoptosis and survival, metastasis, cancer recurrence and chemoresistance. In this review, we will first (i) provide an overview of the miRNA biogenesis pathways, and in vitro and in vivo models for research, (ii) summarize the most recent findings on the roles of microRNAs (miRNAs) that could potentially be used for miRNA-based therapy in the treatment of breast cancer and (iii) discuss the various therapeutic applications.

Nine glycolysis-related gene signature predicting the survival of patients with endometrial adenocarcinoma

Background

Endometrial cancer is the fourth most common cancer in women. The death rate for endometrial cancer has increased. Glycolysis of cellular respiration is a complex reaction and is the first step in most carbohydrate catabolism, which was proved to participate in tumors.

Methods

We analyzed the sample data of over 500 patients from TCGA database. The bioinformatic analysis included GSEA, cox and lasso regression analysis to select prognostic genes, as well as construction of a prognostic model and a nomogram for OS evaluation. The immunohistochemistry staining, survival analysis and expression level validation were also performed. Maftools package was for mutation analysis. GSEA identified Glycolysis was the most related pathway to EC. qRT-PCR verified the expression level of hub gene in clinical samples.

Results

According to the prognostic model using the train set, 9 glycolysis-related genes including B3GALT6, PAM, LCT, GMPPB, GLCE, DCN, CAPN5, GYS2 and FBP2 were identified as prognosis-related genes. Based on nine gene signature, the EC patients could be classified into high and low risk subgroups, and patients with high risk score showed shorter survival time. Time-dependent ROC analysis and Cox regression suggested that the risk score predicted EC prognosis accurately and independently. Analysis of test and train sets yielded consistent results A nomogram which incorporated the 9-mRNA signature and clinical features was also built for prognostic prediction. Immunohistochemistry staining and TCGA validation showed that expression levels of these genes do differ between EC and normal tissue samples. GSEA revealed that the samples of the low-risk group were mainly concentrated on Bile Acid Metabolism. Patients in the low-risk group displayed obvious mutation signatures compared with those in the high-risk group. The expression levels of B3GALT6, DCN, FBP2 and GYS2 are lower in tumor samples and higher in normal tissue samples. The expression of CAPN5 and LCT in clinical sample tissues is just the opposite.

Conclusion

This study found that the Glycolysis pathway is associated with EC and screened for hub genes on the Glycolysis pathway, which may serve as new target for the treatment of EC.

Exosomal MicroRNA-221-3p Confers Adriamycin Resistance in Breast Cancer Cells by Targeting PIK3R1

Drug resistance in breast cancer (BC) cells continues to be a stern obstacle hindering BC treatment. Adriamycin (ADR) is a frequently employed chemotherapy agent used to treat BC. The exosomal transfer of microRNAs (miRNAs) has been reported to enhance the drug-resistance of BC cells. Herein, we first sought to elucidate the possible role of the exosomal transfer of miR-221-3p in the drug resistance of MCF-7 cells to ADR. Differentially expressed genes (DEGs) were initially screened through microarray analysis in BC drug resistance-related datasets. Next, the expression of miR-221-3p and phosphoinositide-3-kinase regulatory subunit 1 (PIK3R1) was quantified in ADR-resistant MCF-7 (MCF-7/ADR) and ADR-sensitive MCF-7 (MCF-7/S) cell lines, after which exosomes were separated and identified in each cell line. Target relationship between miR-221-3p and PIK3R1 was validated by a dual-luciferase reporter assay. Next, the expression of miR-221-3p and PIK3R1 was altered to clarify their effects on the resistance of MCF-7 cells to ADR in vitro and in vivo. PIK3R1 was identified as a BC drug resistance-related DEG, with the regulatory miR-221-3p subsequently obtained. Moreover, the MCF-7/ADR cells exhibited a low expression of PIK3R1 and a high expression of miR-221-3p. Notably, PIK3R1 was identified as a target gene of miR-221-3p. The overexpression of miR-221-3p in MCF-7/ADR cell-derived exosomes promoted ADR resistance in MCF-7/S cells via the PI3K/AKT signaling pathway. The in vitro results were reproducible in in vivo assays. Taken together, drug-resistant BC cell-derived exosomal miR-221-3p can promote the resistance of BC cells to ADR by targeting PIK3R1 via the PI3K/AKT signaling pathway in vitro and in vivo. These findings provide encouraging insights and provide perspectives for further investigation into the BC drug resistance mechanism.

MicroRNA Regulation of the Small Rho GTPase Regulators-Complexities and Opportunities in Targeting Cancer Metastasis

The small Rho GTPases regulate important cellular processes that affect cancer metastasis, such as cell survival and proliferation, actin dynamics, adhesion, migration, invasion and transcriptional activation. The Rho GTPases function as molecular switches cycling between an active GTP-bound and inactive guanosine diphosphate (GDP)-bound conformation. It is known that Rho GTPase activities are mainly regulated by guanine nucleotide exchange factors (RhoGEFs), GTPase-activating proteins (RhoGAPs), GDP dissociation inhibitors (RhoGDIs) and guanine nucleotide exchange modifiers (GEMs). These Rho GTPase regulators are often dysregulated in cancer; however, the underlying mechanisms are not well understood. MicroRNAs (miRNAs), a large family of small non-coding RNAs that negatively regulate protein-coding gene expression, have been shown to play important roles in cancer metastasis. Recent studies showed that miRNAs are capable of directly targeting RhoGAPs, RhoGEFs, and RhoGDIs, and regulate the activities of Rho GTPases. This not only provides new evidence for the critical role of miRNA dysregulation in cancer metastasis, it also reveals novel mechanisms for Rho GTPase regulation. This review summarizes recent exciting findings showing that miRNAs play important roles in regulating Rho GTPase regulators (RhoGEFs, RhoGAPs, RhoGDIs), thus affecting Rho GTPase activities and cancer metastasis. The potential opportunities and challenges for targeting miRNAs and Rho GTPase regulators in treating cancer metastasis are also discussed. A comprehensive list of the currently validated miRNA-targeting of small Rho GTPase regulators is presented as a reference resource.

MiR-629-5p promotes the invasion of lung adenocarcinoma via increasing both tumor cell invasion and endothelial cell permeability

Tumor invasion underlies further metastasis, the leading cause for cancer-related deaths. Deregulation of microRNAs has been identified associated with the malignant behavior of various cancers, including lung adenocarcinoma (LUAD), the major subtype of lung cancer. Here, we showed the significantly positive correlation between miR-629-5p level and tumor invasion in LUAD specimens (n = 49). In a human LUAD metastasis mouse model, H1650 cells (high level of miR-629-5p) were more aggressive than A549 cells (low level of miR-629-5p) in vivo, including higher incidence of vascular invasion and pulmonary colonization. Ectopic expression of miR-629-5p in A549 cells also increased their invasive capability. Then we identified that miR-629-5p promotes LUAD invasion in a mode of dual regulation via tumor cells invasion and endothelial cells permeability, respectively. In tumor cells, miR-629-5p enhanced motility and invasiveness of tumor cells by directly targeting PPWD1 (a cyclophilin), which clinically related to tumor invasion in LUAD specimens. Restoring PPWD1 protein significantly attenuated the invasion-promoting effects of miR-629-5p. Besides, exosomal-miR-629-5p secreted from tumor cells could be transferred to endothelial cells and increased endothelial monolayers permeability by suppressing CELSR1 (a nonclassic-type cadherin), which had a low level in the endothelial cells of invasive LUAD specimens. Activating the expression of CELSR1 in endothelial cells markedly blocked the effect of miR-629-5p. Our study suggests the dual roles of miR-629-5p in tumor cells and endothelial cells for LUAD invasion, implying a therapeutic option to targeting miR-629-5p using the "one stone, two birds" strategy in LUAD.

A smart ATP-responsive chemotherapy drug-free delivery system using a DNA nanostructure for synergistic treatment of breast cancer in vitro and in vivo

This study demonstrated a chemotherapy drug-free delivery system for breast cancer treatment based on a simple DNA nanostructure composed of sequence 1 containing ATP and AS1411 aptamers and sequence 2 containing antimiR-21. The DNA nanostructure was used for co-delivery of KLA peptide and antimiR-21 as antiapoptotic agents. These therapeutic agents could not be internalised into eukaryotic cells freely which is one of the great features of this targeting platform. The presented delivery system was ATP-responsive, leading to disassembly of the DNA nanostructure in high ATP concentration of cancer cells and restoration of the function of antimiR-21 in these cells. The DNA nanostructure was associated with high cellular uptake by MCF-7 and 4T1 cells due to expression of nucleolin as target of AS1411 on their plasma membranes, while the developed targeting platform could not be internalised into CHO cells because of lack of the active targeting moiety on their surfaces. Furthermore, the results showed that co-delivery of antimiR-21 and KLA peptide using the DNA nanostructure could efficiently prohibit tumour growth in vitro and in vivo and induce a synergistic anticancer activity. Thus, this work provides a new ATP-responsive nanotargeting delivery system and synergistic chemotherapy drug-free regimen for cancer treatment.

MicroRNA-21 and microRNA-155 promote the progression of Burkitt's lymphoma by the PI3K/AKT signaling pathway

INTRODUCTION

Burkitt's lymphoma (BL) is a rare and highly aggressive B cell non-Hodgkin lymphoma. High toxicity of chemotherapy for BL treatment causes morbidity and mortality. Many miRNAs have been used as biomarkers for early detection or therapy targets for tumors. However, the roles of miR-21 and miR-155 in Burkitt's lymphoma remain unclear.

METHODS

We collected 15 blood samples from patients with Burkitt's lymphoma and evaluated the expression of miR-21 and miR-155. Then, we knocked down miR-21 and miR-155 expression in Burkitt's lymphoma cell lines and assessed cell proliferation, cell cycle, and apoptosis. Furthermore, we detected the activation of PI3K/AKT pathway by qPCR and western blot. Finally, we predicted the target genes of miR-21 and miR-155 by publicly available databases.

RESULTS

The expression of miR-21 and miR-155 in blood samples from patients with Burkitt's lymphoma were significantly upregulated. Knockdown of miR-21 and miR-155 significantly suppressed cell proliferation, and resulted in S phase arrest and cell apoptosis. The knockdown of miR-21 and miR-155 inhibited the activation of the PI3K/AKT pathway. We found that the target genes of miR-21 and miR-155 were C1RL and TCAP.

CONCLUSION

miR-21 and miR-155 promote the progression of Burkitt's lymphoma through PI3K/AKT signaling by targeting C1RL and TCAP. Our findings will provide a novel biomarker and therapeutic strategies for Burkitt's lymphoma.

Prognostic role of microRNAs in breast cancer: A systematic review

MicroRNAs (miRNAs) have been found to play an important role in breast cancer, functioning either as potential oncogenes or tumor suppressor genes, but their role in the prognosis of patients remains unclear. The aim of the present review study is to highlight recent preclinical and clinical studies performed on both circulating and tissue-specific miRNAs and their potential role as prognostic markers in breast cancer. We systematically searched the PubMed database to explore the prognostic value of miRNAs in breast cancer. After performing the literature search and review, 117 eligible studies were identified. We found that 110 aberrantly expressed miRNAs have been associated with prognosis in breast cancer. In conclusion, the collective data presented in this review indicate that miRNAs could serve as novel prognostic tools in breast cancer, while the clinical application of these findings has yet to be verified.

MicroRNAs in breast cancer: Roles, functions, and mechanism of actions

Breast cancer is one of the most lethal malignancies in women in the world. Various factors are involved in the development and promotion of the malignancy; most of them involve changes in the expression of certain genes, such as microRNAs (miRNAs). MiRNAs can regulate signaling pathways negatively or positively, thereby affecting tumorigenesis and various aspects of cancer progression, particularly breast cancer. Besides, accumulating data demonstrated that miRNAs are a novel tool for prognosis and diagnosis of breast cancer patients. Herein, we will review the roles of these RNA molecules in several important signaling pathways, such as transforming growth factor, Wnt, Notch, nuclear factor-κ B, phosphoinositide-3-kinase/Akt, and extracellular-signal-regulated kinase/mitogen activated protein kinase signaling pathways in breast cancer.

Plasma Level Of miR-21 And miR-451 In Primary And Recurrent Breast Cancer Patients

PURPOSE

MiR-21 and miR-451 are closely associated with tumor initiation, drug resistance, and recurrence of breast cancer (BC). This study was conducted to evaluate the possible value of the plasma level of miR-21 and miR-451 as potential biomarkers for the detection of primary and recurrent BC.

PATIENTS AND METHODS

In this descriptive-analytical study, the plasma level of miR-21 and miR-451 was measured in 23 primary BC patients, 24 recurrent (local/distant metastasis) BC patients, and 24 aged-match women as healthy controls using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Finally, data were analyzed using SPSS software, and the area under the receiver operating characteristic (ROC) curve of miRNAs was measured.

RESULTS

The plasma level of miR-21 was significantly increased in both groups of primary (P<0.001) and recurrent (P<0.001) BC patients in comparison with healthy women. However, the plasma level of miR-451 was not significantly changed in primary (P=0.065) and recurrent (P=0.06) BC patients than healthy controls. The elevation of both miR-21 and miR-451 plasma level was not significantly changed in recurrent patients compared with non-recurrent (primary) patients (P=0.481, and P=1, respectively). Based on the ROC analyses, the areas under the curves (AUC) for miR-21 in discriminating primary BC and recurrent BC patients from healthy controls were 0.828 (95% CI: 0.712 to 0.944) and 0.865 (95% CI: 0.756 to 0.974), respectively.

CONCLUSION

These data indicating that plasma miR-21 may be useful as a biomarker for the detection of both primary and recurrent BC. However, plasma miR-451 lacks enough sensitivity in the detection of primary and recurrent BC, and more studies are needed in this area.

Significant prognostic values of differentially expressed-aberrantly methylated hub genes in breast cancer

Introduction: Abnormal status of gene expression plays an important role in tumorigenesis, progression and metastasis of breast cancer. Mechanisms of gene silence or activation were varied. Methylation of genes may contribute to alteration of gene expression. This study aimed to identify differentially expressed hub genes which may be regulated by DNA methylation and evaluate their prognostic value in breast cancer by bioinformatic analysis. Methods: GEO2R was used to obtain expression microarray data from GSE54002, GSE65194 and methylation microarray data from GSE20713, GSE32393. Differentially expressed-aberrantly methylated genes were identified by FunRich. Biological function and pathway enrichment analysis were conducted by DAVID. PPI network was constructed by STRING and hub genes was sorted by Cytoscape. Expression and DNA methylation of hub genes was validated by UALCAN and MethHC. Clinical outcome analysis of hub genes was performed by Kaplan Meier-plotter database for breast cancer. IHC was performed to analyze protein levels of EXO1 and Kaplan-Meier was used for survival analysis. Results: 677 upregulated-hypomethylated and 361 downregulated-hypermethylated genes were obtained from GSE54002, GSE65194, GSE20713 and GSE32393 by GEO2R and FunRich. The most significant biological process, cellular component, molecular function enriched and pathway for upregulated-hypomethylated genes were viral process, cytoplasm, protein binding and cell cycle respectively. For downregulated-hypermethylated genes, the result was peptidyl-tyrosine phosphorylation, plasma membrane, transmembrane receptor protein tyrosine kinase activity and Rap1 signaling pathway (All p< 0.05). 12 hub genes (TOP2A, MAD2L1, FEN1, EPRS, EXO1, MCM4, PTTG1, RRM2, PSMD14, CDKN3, H2AFZ, CCNE2) were sorted from 677 upregulated-hypomethylated genes. 4 hub genes (EGFR, FGF2, BCL2, PIK3R1) were sorted from 361 downregulated-hypermethylated genes. Differential expression of 16 hub genes was validated in UALCAN database (p<0.05). 7 in 12 upregulated-hypomethylated and 2 in 4 downregulated-hypermethylated hub genes were confirmed to be significantly hypomethylated or hypermethylated in breast cancer using MethHC database (p<0.05). Finally, 12 upregulated hub genes (TOP2A, MAD2L1, FEN1, EPRS, EXO1, MCM4, PTTG1, RRM2, PSMD14, CDKN3, H2AFZ, CCNE2) and 3 downregulated genes (FGF2, BCL2, PIK3R1) contributed to significant unfavorable clinical outcome in breast cancer (p<0.05). High expression level of EXO1 protein was significantly associated with poor OS in breast cancer patients (p=0.03). Conclusion: Overexpression of TOP2A, MAD2L1, FEN1, EPRS, EXO1, MCM4, PTTG1, RRM2, PSMD14, CDKN3, H2AFZ, CCNE2 and downregulation of FGF2, BCL2, PIK3R1 might serve as diagnosis and poor prognosis biomarkers in breast cancer by more research validation. EXO1 was identified as an individual unfavorable prognostic factor. Methylation might be one of the major causes leading to abnormal expression of those genes. Functional analysis and pathway enrichment analysis of those genes would provide novel ideas for breast cancer research.

MicroRNA and mRNA Interaction Network Regulates the Malignant Transformation of Human Bronchial Epithelial Cells Induced by Cigarette Smoke

This study analyzes the correlation and interaction of miRNAs and mRNAs and their biological function in the malignant transformation of BEAS-2B cells induced by cigarette smoke (CS). Normal human bronchial epithelial cells (BEAS-2B) were continuously exposed to CS for 30 passages (S30) to establish an in vitro cell model of malignant transformation. The transformed cells were validated by scratch wound healing assay, transwell migration assay, colony formation and tumorigenicity assay. The miRNA and mRNA sequencing analysis were performed to identify differentially expressed miRNAs (DEMs) and differentially expressed genes (DEGs) between normal BEAS-2B and S30 cells. The miRNA-seq data of lung cancer with corresponding clinical data obtained from TCGA was used to further identify lung cancer-related DEMs and their correlations with smoking history. The target genes of these DEMs were predicted using the miRDB database, and their functions were analyzed using the online tool “Metascape.” It was found that the migration ability, colony formation rate and tumorigenicity of S30 cells enhanced. A total of 42 miRNAs and 753 mRNAs were dysregulated in S30 cells. The change of expression of top five DEGs and DEMs were consistent with our sequencing results. Among these DEMs, eight miRNAs were found dysregulated in lung cancer tissues based on TCGA data. In these eight miRNAs, six of them including miR-96-5p, miR-93-5p, miR-106-5p, miR-190a-5p, miR-195-5p, and miR-1-3p, were found to be associated with smoking history. Several DEGs, including THBS1, FN1, PIK3R1, CSF1, CORO2B, and PREX1, were involved in many biological processes by enrichment analysis of miRNA and mRNA interaction. We identified the negatively regulated miRNA-mRNA pairs in the CS-induced lung cancer, which were implicated in several cancer-related (especially EMT-related) biological process and KEGG pathways in the malignant transformation progress of lung cells induced by CS. Our result demonstrated the dysregulation of miRNA-mRNA profiles in cigarette smoke-induced malignant transformed cells, suggesting that these miRNAs might contribute to cigarette smoke-induced lung cancer. These genes may serve as biomarkers for predicting lung cancer pathogenesis and progression. They can also be targets of novel anticancer drug development.

MicroRNA regulation in colorectal cancer tissue and serum

Colorectal cancer is recognized as the fourth leading cause of cancer-related deaths worldwide. Thus, there is ongoing search for potential new biomarkers allowing quicker and less invasive detection of the disease and prediction of the treatment outcome. Therefore, the aim of our study was to identify colorectal cancer specific miRNAs expressed in cancerous and healthy tissue from the same patient and to further correlate the presence of the same miRNAs in the circulation as potential biomarkers for diagnosis. In the current study we detected a set of 40 miRNAs differentially regulated in tumor tissue when comparing with healthy tissue. Additionally, we found 8 miRNAs differentially regulated in serum of colorectal cancer patients. Interestingly, there was no overlap in miRNAs regulated in tissue and serum, suggesting that serum regulated miRNAs may be not actively secreted from colorectal tumor cells. However, four of differentially expressed miRNAs, including miR-21, miR-17, miR-20a and miR-32 represent the miRNAs characteristic for different tumor types, including breast, colon, lung, pancreas, prostate and stomach cancer. This finding suggests important groups of miRNAs which can be further validated as markers for diagnosis of tumor tissue and regulation of carcinogenesis.

The protective role of DMBT1 in cervical squamous cell carcinoma

To explore the possible influence of deleted in malignant brain tumor 1 (DMBT1) in cervical squamous cell carcinoma (CSCC). DMBT1 expression was detected by Real-time reverse transcription PCR (qRT-PCR) and immunohistochemistry in CSCC and adjacent normal tissues from 167 CSCC patients, and its relationship with clinicopathological features and prognosis was analyzed. Besides, the in vitro experiments, including MTT, Cell-Light EdU, Wound-healing, Transwell invasion, Annexin V-FITC/PI staining, qRT-PCR, and Western blot, were performed in SiHa and CaSKi cells, which were both divided into Blank, Vector, and DMBT1 groups. The mRNA level and the positive expression rate of DMBT1 in CSCC tissues were lower than the adjacent normal tissues. Moreover, DMBT1 positive rate was linked to FIGO stage, tumor diameter, lymph node metastasis, and tumor differentiation of CSCC. Besides, patients with positive DMBT1 expression had higher 5-year survival rate than those negative ones. According to the in vitro experiments, SiHa and CaSKi cells with overexpressed DMBT1 showed the inhibition of proliferative ability and the enhancement of apoptosis with the upregulated pro-apoptosis proteins (Bax and Cleaved caspase-3) and down-regulated anti-apoptosis protein Bcl-2. Moreover, compared with Blank group, DMBT1 group presented decrease in the migration and invasion of SiHa and CaSKi cells with the down-expression of interstitial markers (N-cadherin and Vimentin) and the up-expression of epithelial marker E-cadherin. DMBT1 was decreased in CSCC, whereas its overexpression can not only inhibit the proliferation, migration, and invasion, but induce the apoptosis of human CSCC cells, being a novel strategy for CSCC treatment.

MiR-486-5p Serves as a Good Biomarker in Nonsmall Cell Lung Cancer and Suppresses Cell Growth With the Involvement of a Target PIK3R1

MicroRNAs are a class of noncoding RNAs that can be involved in the regulation of gene expression in cancers, including lung cancer. Our previous research has shown that miR-486-5p is one of the most downregulated microRNAs in tissue and serum samples of lung cancer as a good diagnostic biomarker. The objective of this study is to investigate the roles of miR-486-5p in the progression of lung cancer. In this study, miR-486-5p was further validated to be significantly downregulated in additional nonsmall cell lung cancer (NSCLC) tissue, serum, and cell samples by quantitative reverse transcription-polymerase chain reaction (RT-PCR), and the expression level of miR-486-5p was significantly associated with clinical phenotype of NSCLC. The PIK3R1 gene was confirmed to be a direct target of miR-486-5p by dual-luciferase reporter assay, and the expression level of miR-486-5p was inversely correlated with that of PIK3R1 in tumor tissues (r = −0.774, p < 0.01). Overexpressed miR-486-5p effectively inhibited cell proliferation and invasion and successfully induced apoptosis in vitro. PIK3R1 was involved in the suppression of miR-486-5p on cell growth. It can be concluded that miR-486-5p may act as a tumor suppressor contributing to the progression of NSCLC, and miR-486-5p would be a diagnostic and prognostic biomarker and a potential therapeutic target for lung cancer.

ENKUR acts as a tumor suppressor in lung adenocarcinoma cells through PI3K/Akt and MAPK/ERK signaling pathways

Lung adenocarcinoma (LAD) is the most common type of lung cancer with a high possibility of tumor relapse and metastasis. ENKUR (Enkurin) was originally identified as a potential regulator or effector of TRPC channels that directly binds to several TRPC proteins and the p85 subunit of PI3K. However, the role of ENKUR in cancer development has remained unclear. In this study we analyzed the expression profile of ENKUR mRNA in clinical LAD samples and examined ENKUR mRNA expression and ENKUR protein level in LAD cells. Significant down-regulated ENKUR expression was observed in clinical tumor tissues of LAD as well as in human LAD cells. To evaluate the effects of aberrant ENKUR expression on cellular biology of LAD cells in vitro and tumor growth in vivo, ENKUR-overexpressed and -silenced LAD cell lines were constructed using lentiviral vectors. Our results showed that overexpression of ENKUR in LAD cells inhibited cell proliferation, migration and invasion, while silencing of ENKUR led to the opposite effects. Silencing of ENKUR in LAD cells also promoted tumorigenesis in nude mice model and caused epithelial to mesenchymal transition (EMT). Furthermore, using western blot and co-immunoprecipitation analyses, we demonstrated that ENKUR interacts with PI3K directly and is possibly involved in the PI3K/Akt and MAPK/ERK signaling pathways.

Erlotinib inhibits colon cancer metastasis through inactivation of TrkB-dependent ERK signaling pathway

The distal metastasis is the main cause of death in patients with colon cancer. Tyrosine receptor kinase B (TrkB) and ERK signals may be the potential targets for the treatment of colon cancer metastasis. This study aims to investigate whether erlotinib inhibits distant metastasis of colon cancer by regulating TrkB and ERK signaling pathway. Human colon adenocarcinoma cell lines (SW480 and Caco-2) pretreated with exogenous C-X-C motif chemokine ligand 8 (CXCL8) were used to assess the suppressive effect of erlotinib on tumor metastasis, including anoikis, epithelial-mesenchymal transformation (EMT), migration, and invasion. Through TrkB overexpression, Akt suppression, and ERK suppression, the roles of TrkB, Akt, and ERK in erlotinib-induced metastasis inhibition of colon cancer cells were explored. The results showed that erlotinib alleviated CXCL8-induced metastasis of the colon cancer cells. Overexpression of TrkB in colon cancer cells eliminated the effect of erlotinib on anoikis, inhibition of EMT, migration, and invasion, and downregulation of p-ERK and p-Akt. Furthermore, the inhibition of ERK activation instead of Akt activation was found to participate in erlotinib-mediated metastasis resistance, including anoikis, inhibition of EMT, migration, and invasion. In conclusion, erlotinib inhibits colon cancer cell anoikis resistance, EMT, migration, and invasion by inactivating TrkB-dependent ERK signaling pathway.

Immunoprofiling of Breast Cancer Antigens Using Antibodies Derived from Local Lymph Nodes

Tumor antigens are responsible for initiating an immune response in cancer patients, and their identification may provide new biomarkers for cancer diagnosis and targets for immunotherapy. The general use of serum antibodies to identify tumor antigens has several drawbacks, including dilution, complex formation, and background reactivity. In this study, antibodies were generated from antibody-secreting cells (ASC) present in tumor-draining lymph nodes of 20 breast cancer patients (ASC-probes) and were used to screen breast cancer cell lines and protein microarrays. Half of the ASC-probes reacted strongly against extracts of the MCF-7 breast cancer cell line, but each with a distinct antigen recognition profile. Three of the positive ASC-probes reacted differentially with recombinant antigens on a microarray containing cancer-related proteins. The results of this study show that lymph node-derived ASC-probes provide a highly specific source of tumor-specific antibodies. Each breast cancer patient reacts with a different antibody profile which indicates that targeted immunotherapies may need to be personalized for individual patients. Focused microarrays in combination with ASC-probes may be useful in providing immune profiles and identifying tumor antigens of individual cancer patients.

Identification of LIFR, PIK3R1, and MMP12 as Novel Prognostic Signatures in Gallbladder Cancer Using Network-Based Module Analysis

Background: Gallbladder cancer (GBC) is a rare and aggressive malignancy of the biliary tract with a dismal survival rate. Effective biomarkers and therapeutic targets are urgently needed.

Methods: We analyzed gene expression profiles of GBC to identify differentially expressed genes (DEGs) and then used these DEGs to identify functional module biomarkers based on protein functional interaction (FI) networks. We further evaluated the module-gene protein expression and clinical significance with immunohistochemistry staining (IHC) in a tissue microarray (TMA) from 80 GBC samples.

Results: Five functional modules were identified. Module 0 included classical cancer signaling pathways, such as Ras and PI3K-Akt; and modules 1–4 included genes associated with muscle cells, fibrinogen, extracellular matrix, and integrins, respectively. We validated the expression of LIFR, PIK3R1, and MMP12, which were hubs or functional nodes in modules. Compared with paired peritumoural tissues, we found that the expression of LIFR (P = 0.002) and PIK3R1 (P = 0.046) proteins were significantly downregulated, and MMP12 (P = 0.006) was significantly upregulated. Further prognostic analysis showed that patients with low expression of LIFR had shorter overall survival than those with high expression (log-rank test P = 0.028), the same trend as for PIK3R1 (P = 0.053) and MMP12 (P = 0.006). Multivariate analysis indicated that expression of MMP12 protein (hazard ratio [HR] = 0.429; 95% confidence interval [CI] 0.198, 0.930; P = 0.032) was one of the significant independent prognostic factors for overall survival.

Conclusions: We found a highly reliable FI network, which revealed LIFR, PIK3R1, and MMP12 as novel prognostic biomarker candidates for GBC. These findings could accelerate biomarker discovery and therapeutic development in this cancer.