miR-25 enhances cell migration and invasion in non-small-cell lung cancer cells via ERK signaling pathway by inhibiting KLF4

MACC1 ablation suppresses the dedifferentiation process of non-CSCs in lung cancer through stabilizing KLF4

Metastasis-associated in colon cancer-1 (MACC1) was identified as a new player in lung cancer development, and some stemness-related genes can be novel transcriptional targets of MACC1. Cancer stem cells (CSCs) are responsible for sustaining tumorigenesis and plasticity. Both CSCs and non-CSCs are plastic and capable of undergoing phenotypic transition, especially the dedifferentiation of non-CSCs switch to CSC-like cells. However, the precise role of MACC1 during this process is largely unknown. Here, we showed that MACC1 promoted the transition from non-CSC to CSC in lung cancer. We found MACC1 was overexpressed in stemness enriched cells, enhancing the transition from no-CSCs to CSCs, while short-hairpin RNA-mediated Knockdown of MACC1 impaired this process. High-throughput sequencing and tumor specimen analysis revealed that MACC1 was negative correlated with Krüppel-like factor 4 (KLF4) expression level, which acts as a negative stemness regulator in lung cancer. Mechanistically, MACC1 delays the degradation of KLF4 mRNA by repressing the expression of microRNA-25, thereby promoting the KLF4 mRNA stabilization at the post-transcriptional level. Collectively, our findings may facilitate efforts to promote the development of precision targeted therapy for cancer stem cells in lung cancer.

Enhancement of endothelial function and attenuation of portal vein injury using mesenchymal stem cells carrying miRNA-25-3p

The aims of this study were to determine whether human umbilical cord mesenchymal stem cells (hucMSCs) modified by miRNA-25-3p (miR-25-3p) overexpression could promote venous endothelial cell proliferation and attenuate portal endothelial cell injury. HucMSCs and human umbilical vein endothelial cells (HUVEC) were isolated and cultured from human umbilical cord and characterized. Lentiviral vectors expressing miRNA-25-3p were transfected into hucMSCs and confirmed by PCR. We verified the effect of miR-25-3p-modified hucMSCs on HUVEC by cell co-culture and cell supernatant experiments. Subsequently, exosomes of miR-25-3p-modified hucMSCs were isolated from cell culture supernatants and characterized by WB, NTA and TEM. We verified the effects of miR-25-3p-modified exosomes derived from hucMSCs on HUVEC proliferation, migration, and angiogenesis by in vitro cellular function experiments. Meanwhile, we further examined the downstream target genes and signaling pathways potentially affected by miR-25-3p-modified hucMSC-derived exosomes in HUVEC. Finally, we established a rat portal vein venous thrombosis model by injecting CM-DiR-labeled hucMSCs intravenously into rats and examining the homing of cells in the portal vein by fluorescence microscopy. Histological and immunohistochemical experiments were used to examine the effects of miRNA-25-3p-modified hucMSCs on the proliferation and damage of portal vein endothelial cells. Primary hucMSCs and HUVECs were successfully isolated, cultured and characterized. Primary hucMSCs were modified with a lentiviral vector carrying miR-25-3p at MOI 80. Co-culture and cell supernatant intervention experiments showed that overexpression of miRNA-25-3p in hucMSCs enhanced HUVEC proliferation, migration and tube formation in vitro. We successfully isolated and characterized exosomes of miR-25-3p-modified hucMSCs, and exosome intervention experiments demonstrated that miR-25-3p-modified exosomes derived from hucMSCs similarly enhanced the proliferation, migration, and angiogenesis of HUVECs. Subsequent PCR and WB analyses indicated PTEN/KLF4/AKT/ERK1/2 as potential pathways of action. Analysis in a rat portal vein thrombosis model showed that miR-25-3p-modified hucMSCs could homing to damaged portal veins. Subsequent histological and immunohistochemical examinations demonstrated that intervention with miR-25-3p overexpression-modified hucMSCs significantly reduced damage and attenuated thrombosis in rat portal veins. The above findings indicate suggest that hucMSCs based on miR-25-3p modification may be a promising therapeutic approach for use in venous thrombotic diseases.

MicroRNA‑mediated regulation in lung adenocarcinoma: Signaling pathways and potential therapeutic implications (Review)

Lung adenocarcinoma (LUAD) poses a significant global health burden owing to its high incidence rate and unfavorable prognosis, driven by frequent recurrence and drug resistance. Understanding the biological mechanisms underlying LUAD is imperative to developing advanced therapeutic strategies. Recent research has highlighted the role of dysregulated microRNAs (miRNAs) in LUAD progression through diverse signaling pathways, including the Wnt and AKT pathways. Of particular interest is the novel pathological mechanism involving the interaction between competing endogenous RNAs (ceRNAs) and miRNAs. This review critically analyzed the impact of aberrant miRNA expression on LUAD development, shedding light on the associated signaling pathways. It also highlighted the emerging significance of ceRNA‑miRNA interactions in LUAD pathogenesis. Elucidating the intricate regulatory networks involving miRNAs and ceRNAs presents a promising avenue for the development of potential therapeutic interventions and diagnostic biomarkers in LUAD. Further research in this area is essential to advance precision medicine approaches and improve patient outcomes.

Molecular Mechanisms of Tumor Cell Stemness Modulation during Formation of Spheroids

Cancer stem cells (CSCs), their properties and interaction with microenvironment are of interest in modern medicine and biology. There are many studies on the emergence of CSCs and their involvement in tumor pathogenesis. The most important property inherent to CSCs is their stemness. Stemness combines ability of the cell to maintain its pluripotency, give rise to differentiated cells, and interact with environment to maintain a balance between dormancy, proliferation, and regeneration. While adult stem cells exhibit these properties by participating in tissue homeostasis, CSCs behave as their malignant equivalents. High tumor resistance to therapy, ability to differentiate, activate angiogenesis and metastasis arise precisely due to the stemness of CSCs. These cells can be used as a target for therapy of different types of cancer. Laboratory models are needed to study cancer biology and find new therapeutic strategies. A promising direction is three-dimensional tumor models or spheroids. Such models exhibit properties resembling stemness in a natural tumor. By modifying spheroids, it becomes possible to investigate the effect of therapy on CSCs, thus contributing to the development of anti-tumor drug test systems. The review examines the niche of CSCs, the possibility of their study using three-dimensional spheroids, and existing markers for assessing stemness of CSCs.

Extracellular Vesicles: A New Source of Biomarkers in Pediatric Solid Tumors? A Systematic Review

Virtually every cell in the body releases extracellular vesicles (EVs), the contents of which can provide a "fingerprint" of their cellular origin. EVs are present in all bodily fluids and can be obtained using minimally invasive techniques. Thus, EVs can provide a promising source of diagnostic, prognostic, and predictive biomarkers, particularly in the context of cancer. Despite advances using EVs as biomarkers in adult cancers, little is known regarding their use in pediatric cancers. In this review, we provide an overview of published clinical and in vitro studies in order to assess the potential of using EV-derived biomarkers in pediatric solid tumors. We performed a systematic literature search, which yielded studies regarding desmoplastic small round cell tumor, hepatoblastoma, neuroblastoma, osteosarcoma, and rhabdomyosarcoma. We then determined the extent to which the in vivo findings are supported by in vitro data, and vice versa. We also critically evaluated the clinical studies using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) system, and we evaluated the purification and characterization of EVs in both the in vivo and in vitro studies in accordance with MISEV guidelines, yielding EV-TRACK and PedEV scores. We found that several studies identified similar miRNAs in overlapping and distinct tumor entities, indicating the potential for EV-derived biomarkers. However, most studies regarding EV-based biomarkers in pediatric solid tumors lack a standardized system of reporting their EV purification and characterization methods, as well as validation in an independent cohort, which are needed in order to bring EV-based biomarkers to the clinic.

Intrinsic and Extrinsic Factors Impacting Cancer Stemness and Tumor Progression

Tumor heterogeneity represents an important limitation to the development of effective cancer therapies. The presence of cancer stem cells (CSCs) and their differentiation hierarchies contribute to cancer complexity and confer tumors the ability to grow, resist treatment, survive unfavorable conditions, and invade neighboring and distant tissues. A large body of research is currently focusing on understanding the properties of CSCs, including their cellular and molecular origin, as well as their biological behavior in different tumor types. In turn, this knowledge informs strategies for targeting these tumor initiating cells and related cancer stemness. Cancer stemness is modulated by the tumor microenvironment, which influences CSC function and survival. Several advanced in vitro models are currently being developed to study cancer stemness in order to advance new knowledge of the key molecular pathways involved in CSC self-renewal and dormancy, as well as to mimic the complexity of patients' tumors in pre-clinical drug testing. In this review, we discuss CSCs and the modulation of cancer stemness by the tumor microenvironment, stemness factors and signaling pathways. In addition, we introduce current models that allow the study of CSCs for the development of new targeted therapies.

Expression of miRNA-25 in young and old lung adenocarcinoma

Background:

An appropriate personalized molecular testing ensures the most efficacious treatment in lung cancer. It is still controversial whether younger lung adenocarcinoma (LUAD) patients have different molecular features compared with their older counterparts. MicroRNAs have been involved in lung cancer and their altered expression has been suggested as a potential biomarker in the pathogenesis, diagnosis, prognosis, and therapy of LUAD.

Materials and Methods:

To analyze putative differences in miR-25 expression between young (with age ≤50 years) and old adenocarcinoma patients, we quantified miR-25 levels with NanoString technology in 88 LUAD specimens. We further investigated a cohort of 309 LUAD patients from the cancer genome atlas (TCGA) database to test our hypothesis.

Results:

miR-25 expression was upregulated in young LUAD patients in comparison to the older ones (P = 0.03) in our series. The analysis of public database TCGA confirmed our results, which miR-25 differentially expressed in the two aged groups (P = 0.0009). Moreover, a consequential pairing of miR-25 with a target region in phosphatase and tensin homolog (PTEN) 3’ untranslated region (UTR) and actually low PTEN expression seemed to be associated with high miR-25 (P = 0.001) in young patients.

Conclusions:

The interaction of miR-25 and PTEN in young LUAD may define a subgroup of patients, highlighting the concept of molecular testing in different age subtypes.

MicroRNA-25 promotes cell proliferation, migration and invasion in glioma by directly targeting cell adhesion molecule 2

Numerous microRNAs (miRNAs/miRs) have been demonstrated to serve oncogenic or suppressive roles in glioma. Exploration of the underlying molecular mechanism of miRNAs in the development and progression of glioma is beneficial for the identification of novel therapeutic targets. In the present study, the function of miR-25 in glioma progression, as well as its underlying mechanism, were investigated. It was determined that miR-25 was significantly upregulated in glioma tissues and cell lines compared with normal brain tissues and cells, respectively. Furthermore, high expression levels of miR-25 were associated with an advanced clinical stage. The knockdown of miR-25 expression significantly reduced glioma cell proliferation, migration and invasion. Cell adhesion molecule 2 (CADM2) was identified as a direct target of miR-25 in glioma cells. Moreover, CADM2 expression level was significantly downregulated and inversely correlated with miR-25 expression level in glioma tissues, indicating that the expression of CADM2 was negatively regulated by miR-25. The inhibition of CADM2 expression counteracted the effects on glioma cell proliferation, migration and invasion caused by miR-25 downregulation. Furthermore, CADM2 knockdown considerably promoted the proliferation and migration of glioma cells. In summary, the present study demonstrated that miR-25 was significantly upregulated in glioma and that it promoted glioma cell proliferation, migration and invasion, at least partially, by directly targeting CADM2. These findings expanded the understanding of the molecular mechanism that underlies glioma progression.

MicroRNAs' role in the environment-related non-communicable diseases and link to multidrug resistance, regulation, or alteration

The discovery of microRNAs (miRNAs) 20 years ago has advocated a new era of "small molecular genetics." About 2000 miRNAs are present that regulate one third of the genome. MiRNA dysregulated expression arising as a response to our environment insult or stress or changes may contribute to several diseases, namely non-communicable diseases, including tumor growth. Their presence in body fluids, reflecting level alteration in various cancers, merit circulating miRNAs as the "next-generation biomarkers" for early-stage tumor diagnosis and/or prognosis. Herein, we performed a comprehensive literature search focusing on the origin, biosynthesis, and role of miRNAs and summarized the foremost studies centering on miR value as non-invasive biomarkers in different environment-related non-communicable diseases, including various cancer types. Moreover, during chemotherapy, many miRNAs were linked to multidrug resistance, via modulating numerous, environment triggered or not, biological processes and/or pathways that will be highlighted as well.

Current research advances in microRNA-mediated regulation of Krüppel-like factor 4 in cancer: a narrative review

Objective

The purpose of this study was to investigate the miRNAs and related mechanisms that regulates KLF4 in different cancers. Furthermore, we summarized the potential targets of miRNAs regulating the KLF4 pathway in cancer research.

Background

MiRNAs are single-stranded, endogenous non-coding small RNAs, some of which are related to human cancers. miRNAs carry out post-transcriptional gene regulation through translation inhibition and degradation of target messenger RNAs (mRNAs) via complementarily pairing with their 3' untranslated regions. KLF4 is an important transcription factor with complex involvement in cancer. Increasing evidence shows that miRNAs are dysregulated in cancer and can regulate cancer-related signaling pathways, thereby affecting tumor progression.

Methods

Systematic scientific literature searches were undertaken on PubMed using the following terms: "miRNAs and KLF4", "KLF4 and cancer", "miRNAs and cancer", and "miRNAs, KLF4 and cancer". Relevant papers were retrieved and further results were found by reviewing related papers and the references of the retrieved papers. We then conducted a narrative overview of the literature to summarize the results of the papers.

Conclusions

The role of KLF4 in cancer varies in a context-dependent manner. KLF4-regulating miRNAs in different tumors include miR-124, miR-9-5p, miR-10b, miR-18a, miR-25-3p, miR-10b, miR-92a, miR-103, miR-155, miR-135b-5p, miR-32-5p, miR-148-3p, miR-152-3p, miR-10b, miR-25, miR-3120-5p, miR-7, miR-1233-3p, miR-10b, miR-145, miR-139-5p, miR-16, miR-152, miR-375, and miR-145.

Recent Discoveries on the Involvement of Krüppel-Like Factor 4 in the Most Common Cancer Types

Krüppel-like factor 4 (KLF4) is a transcription factor highly conserved in evolution. It is particularly well known for its role in inducing pluripotent stem cells. In addition, KLF4 plays many roles in cancer. The results of most studies suggest that KLF4 is a tumor suppressor. However, the functioning of KLF4 is regulated at many levels. These include regulation of transcription, alternative splicing, miRNA, post-translational modifications, subcellular localization, protein stability and interactions with other molecules. Simple experiments aimed at assaying transcript levels or protein levels fail to address this complexity and thus may deliver misleading results. Tumor subtypes are also important; for example, in prostate cancer KLF4 is highly expressed in indolent tumors where it impedes tumor progression, while it is absent from aggressive prostate tumors. KLF4 is important in regulating response to many known drugs, and it also plays a role in tumor microenvironment. More and more information is available about upstream regulators, downstream targets and signaling pathways associated with the involvement of KLF4 in cancer. Furthermore, KLF4 performs critical function in the overall regulation of tissue homeostasis, cellular integrity, and progression towards malignancy. Here we summarize and analyze the latest findings concerning this fascinating transcription factor.

Deregulated microRNAs Are Associated with Patient Survival and Predicted to Target Genes That Modulate Lung Cancer Signaling Pathways

(1) Background: Although the advances in diagnostic and treatment strategies, lung cancer remains the leading cause of cancer-related deaths, worldwide, with survival rates as low as 16% in developed countries. Low survival rates are mainly due to late diagnosis and the lack of effective treatment. Therefore, the identification of novel, clinically useful biomarkers is still needed for patients with advanced disease stage and poor survival. Micro(mi)RNAs are non-coding RNAs and potent regulators of gene expression with a possible role as diagnostic, prognostic and predictive biomarkers in cancer. (2) Methods: We applied global miRNA expression profiling analysis using TaqMan® arrays in paired tumor and normal lung tissues (n = 38) from treatment-naïve patients with lung adenocarcinoma (AD; n = 23) and lung squamous cell carcinoma (SCC; n = 15). miRNA target genes were validated using The Cancer Genome Atlas (TCGA) lung AD (n = 561) and lung SCC (n = 523) RNA-Seq datasets. (3) Results: We identified 33 significantly deregulated miRNAs (fold change, FC ≥ 2.0 and p < 0.05) in tumors relative to normal lung tissues, regardless of tumor histology. Enrichment analysis confirmed that genes targeted by the 33 miRNAs are aberrantly expressed in lung AD and SCC, and modulate known pathways in lung cancer. Additionally, high expression of miR-25-3p was significantly associated (p < 0.05) with poor patient survival, when considering both tumor histologies. (4) Conclusions: miR-25-3p may be a potential prognostic biomarker in non-small cell lung cancer. Genes targeted by miRNAs regulate EGFR and TGFβ signaling, among other known pathways relevant to lung tumorigenesis.

Hsa_circ_0043265 Suppresses Proliferation, Metastasis, EMT and Promotes Apoptosis in Non-Small Cell Lung Cancer Through miR-25-3p/FOXP2 Pathway

Purpose

Non-small cell lung cancer (NSCLC) is the largest type of lung cancer (LC) with a higher mortality rate. Circular RNAs (circRNAs) have been shown to play an important role in cancer progression. Therefore, this study was to explore the function of hsa_circ_0043265 in NSCLC.

Methods

The expression levels of hsa_circ_0043265, microRNA-25-3p (miR-25-3p) and forkhead box P2 (FOXP2) were determined by quantitative real-time polymerase chain reaction (qRT-PCR). Ribonuclease R (RNase R) and Actinomycin D (ActD) were used to verify the authenticity and stability of hsa_circ_0043265. Cell counting kit-8 (CCK-8), flow cytometry and transwell assays were used to evaluate the abilities of proliferation, apoptosis, migration and invasion of NSCLC cells. Also, Western blot (WB) analysis was performed to assess the levels of apoptosis, epithelial–mesenchymal transition (EMT) and proliferation-related proteins and FOXP2 protein. RNA immunoprecipitation (RIP) and dual-luciferase reporter assays were used to verify the interaction between miR-25-3p and hsa_circ_0043265 or FOXP2. Besides, mice xenograft models were constructed to confirm the effect of hsa_circ_0043265 on NSCLC tumor growth in vivo.

Results

Hsa_circ_0043265 was lowly expressed in NSCLC tissues and cells, and its overexpression inhibited the proliferation, migration, invasion and EMT process, while improved the apoptosis of NSCLC cells. MiR-25-3p could be sponged by hsa_circ_0043265, and its overexpression could invert the suppression effect of overexpressed-hsa_circ_0043265 on NSCLC progression. Moreover, FOXP2 was a target of miR-25-3p, and its silencing also could reverse the inhibition effect of overexpressed-hsa_circ_0043265 on NSCLC progression. In addition, hsa_circ_0043265 overexpression reduced the tumor growth of NSCLC in vivo.

Conclusion

Hsa_circ_0043265 could sponge miR-25-3p to improve FOXP2 expression, thereby inhibiting NSCLC progression. This study showed that hsa_circ_0043265 could be a potential biomarker for early diagnosis of NSCLC.

miR-25 promotes invasion of human non-small cell lung cancer via CDH1

MicroRNA-25 (miR-25) has been reported to be overexpressed in numerous human tumors and plays a key role in tumor promotor. However, there are few reports about miR-25 expression and function in non-small cell lung cancer (NSCLC). In this study, we investigated the biological role of miR-25 in NSCLC and its underlying molecular mechanisms. We found that the upregulation of miR-25 was correlated with lymph node metastasis and TNM stage in 113 NSCLC patients. Moreover, the up-regulation of miR-25 was associated with poor survival of NSCLC patients and might be used as an independent prognostic factor. Moreover, forced expression of miR-25 enhanced H358 and Calu-1 cell migration and invasion, but not apoptosis and proliferation in vitro. Elevation of invasion and metastasis by miR-25 directly and significantly correlated with inactivation of CDH1 expression. Therefore, patients with up-regulated miR-25 are prone to lymph node metastasis and thus have a poor prognosis.

MiR-92a Family: A Novel Diagnostic Biomarker and Potential Therapeutic Target in Human Cancers

Purpose: This study tried to explore whether members of miR-92a family contribute to early diagnosis and prognosis for human cancers and how they work.

Methods: Integrated meta-analysis retrieved from public repositories was employed to assess the clinical roles of the miR-92a family for cancer diagnosis and prognosis. Expression level of miR-92a was detected by the TCGA database and was confirmed by non-small-cell lung cancer (NSCLC) tissues. Targets of miR-92a were predicted using starbase, and validated by dual luciferase assay. Correlation between miR-92a and the target gene was assessed by linkedOmics while expression of the target gene and its role in cancer prognosis were analyzed with UALCAN and Gepia.

Results: We recognized the miR-92a family could serve as a potential diagnostic biomarker with a pooled sensitivity of 0.85 [0.81–0.88] and specificity of 0.86 [0.83–0.90]. The overall hazard ratio (HR) was 2.26 [95% CI: 1.70–3.00] for high expression groups compared to low expression groups. Expression of miR-92a was identified to be upregulated in NSCLC, especially in lung squamous cell carcinoma (LUSC). Results from starbase and dual luciferase assay indicated the regulator of G-protein signaling 3 (RGS3) was a direct target of miR-92a. Statistical negative correlation was found for the expression of miR-92a and RGS3. In addition, expression of RGS3 was downregulated in NSCLC and patients with the high expression had a poor prognosis (HR = 1.3) for LUSC patients. However, results were to the contrary for lung adenocarcinoma (HR = 0.7).

Conclusion: This study revealed that miR-92a family could be ideal biomarkers for cancer diagnosis and prognosis, which might function through targeting RGS3.

KLF4 overexpression decreases the viability, invasion and migration of papillary thyroid cancer cells

Kruppel-like factor 4 (KLF4) has been implicated in a number of different types of cancer; however, the role of KLF4 in papillary thyroid cancer remains elusive. The present study aimed to investigate the role of KLF4 in papillary thyroid cancer and its potential underlying molecular mechanisms. The expression of KLF4 in thyroid tumor tissue and adjacent non-cancerous tissues were detected via immunohistochemistry and western blotting. The papillary thyroid cancer cell line, KTC1, was transfected with viruses carrying KLF4 overexpression vectors. The relative expression of KLF4, E-cadherin, N-cadherin, Vimentin, matrix metalloproteinase (MMP)2, MMP9 and collagen was detected via quantitative-PCR. The viability of KTC1 cells was detected using a cell counting kit-8 assay at 24, 48 and 72 h. Cell invasion was examined via a transwell invasion assay. Cell migration was examined via a scratch migration assay at 0 and 24 h. Compared with adjacent non-cancerous tissues, the expression of KLF4 was significantly lower in thyroid tumor tissues. The expression of KLF4 in KTC1 cells were significantly increased compared with the blank or negative control groups. The expression of N-cadherin, MMP2, MMP9 and collagen was significantly decreased in the KLF4 overexpression group. The viability of KTC1 cells was markedly decreased in KLF4 overexpression group at 24, 48 and 72 h when compared with the blank or negative control groups. The invasion of KTC1 cells in the KLF4 overexpression group was markedly decreased. Compared with the negative control group, the KTC1 cell migration in the KLF4 overexpression group was markedly decreased at 24 h. The expression of KLF4 was also significantly lower in thyroid tumor tissues. The cell viability, tumor invasion and migration ability and expression levels of N-cadherin, MMP2, MMP9 and collagen in papillary thyroid cancer cells were markedly decreased with KLF4 overexpression.

Diagnostic Value of Plasma MicroRNAs for Lung Cancer Using Support Vector Machine Model

Aim: Small single-stranded non-coding RNAs (miRNAs) play an important role in carcinogenesis through degrading target mRNAs. However, the diagnostic value of miRNAs was not explored in lung cancers. In this study, a support-vector-machine (SVM) model for diagnosis of lung cancer was established based on plasma miRNAs biomarkers, clinical symptoms and epidemiology material.

Methods: The expressions of plasma miRNA were examined with SYBR Green-based quantitative real-time PCR.

Results: We identified that the expressions of 10 plasma miRNAs (miR-21, miR-20a, miR-210, miR-145, miR-126, miR-223, miR-197, miR-30a, miR-30d, miR-25), smoking status, fever, cough, chest pain or tightness, bloody phlegm, haemoptysis, were significantly different between lung cancer and control groups (P<0.05). The accuracies of the combined SVM, miRNAs SVM, symptom SVM, combined Fisher, miRNAs Fisher and symptom Fisher were 96.34%, 80.49%, 84.15%, 84.15%, 75.61%, and 80.49%, respectively; AUC of these six model were 0.976, 0.841, 0.838, 0.865, 0.750, and 0.801, respectively. The accuracy and AUC of combined SVM were higher than the other 5 models (P<0.05).

Conclusions: Our findings indicate that SVM model based on plasma miRNAs biomarkers may serve as a novel, accurate, noninvasive method for auxiliary diagnosis of lung cancer.

Overexpression of miR-25 is associated with progression and poor prognosis of cholangiocarcinoma

Cholangiocarcinoma (CCA) is a rare but highly aggressive type of malignancy. MicroRNA (miR)-25 has been demonstrated to be involved in the genesis of numerous cancer types. The aim of the present study was to investigate the prognostic value and functional role of miR-25 in CCA. The expression of miR-25 was determined by reverse transcription-quantitative (RT-q)PCR. The association between miR-25 expression and clinicopathological features was analyzed using the χ² test. Kaplan-Meier survival analysis and Cox linear regression were performed to explore the prognostic value of miR-25. The effects of miR-25 on the biological behavior of CCA cells were determined using loss-and gain-of-function experiments in CCA cell lines. Upregulated miR-25 expression was observed in CCA tissues and cell lines compared with that in the respective controls (all P<0.05). Patients with high expression of miR-25 in CCA tissues had a comparatively higher tumor-nodes-metastasis stage (P=0.026), a higher rate of lymph node metastasis (P=0.032) and a shorter overall survival rate (log-rank P=0.022). miR-25 was determined to be an independent prognostic factor for CCA patients (P=0.036). In vitro, transfection with miR-25 inhibitor suppressed cell viability, migration and invasion, while miR-25 mimics had the opposite effect. These results indicated that miR-25 functions as an oncogene and is involved in tumor progression in CCA. miR-25 may serve as a prognostic biomarker and a potential therapeutic target for CCA treatment.

miR-25 Promotes Cell Proliferation, Migration, and Invasion of Non-Small-Cell Lung Cancer by Targeting the LATS2/YAP Signaling Pathway

Metastasis is the leading cause of high mortality in lung cancer patients, and metastatic lung cancer is difficult to treat. miRNAs are involved in various biological processes of cancer, including metastasis. Our previous studies revealed that miR-25 promoted non-small-cell lung cancer (NSCLC) cell proliferation and suppressed cell apoptosis by directly targeting TP53 and MOAP1. In this work, we further explored the miR-25 expression in NSCLC patients in the Cancer Genome Atlas (TCGA) database and measured the miR-25 expression levels in the tissues of NSCLC patients and cell lines. miR-25 was overexpressed in both NSCLC tissues and cell lines. NSCLC patients who expressed a higher level of miR-25 exhibited worse overall survival than those with a lower level of miR-25. Overexpression of miR-25 enhanced NSCLC cell migration and invasion, while the inhibition of miR-25 exhibited the opposite effects. We identified the large tumor suppressor homology 2 (LATS2) as a new target gene of miR-25 in lung cancer. The effects of miR-25 on promoting NSCLC cell migration and invasion were at least partially due to activation of the Hippo signaling pathway. Additionally, miR-25 antagomir inhibited xenograft tumor growth and metastasis by the upregulation of LATS2. Taken together, our findings demonstrate that miR-25 contribute to lung cancer cell proliferation and metastasis by targeting the LATS2/YAP signaling pathway, which implicate miR-25 as a promising therapeutic target for lung cancer metastasis. Given that oxidative stress induces the overexpression of miR-25 and plays a critical role in cancer progression, this study establishes miR-25 as an intermediate between oxidative stress and lung cancer metastasis.

Identification of candidate biomarkers correlated with the diagnosis and prognosis of cervical cancer via integrated bioinformatics analysis

Background: Cervical carcinoma is one of the most common malignant gynecological tumors and is associated with high rates of morbidity and mortality. Early diagnosis and early treatment can reduce the mortality rate of cervical cancer. However, there is still no specific biomarkers for the diagnosis and detection of cervical cancer prognosis. Therefore, it is greatly urgent in searching biomarkers correlated with the diagnosis and prognosis of cervical cancer.

Results: The mRNA and microRNA expression profile datasets (GSE7803, GSE9750, GSE63514, and GSE30656) were downloaded from the Gene Expression Omnibus database (GEO). The three microarray datasets were integrated to one via integrated bioinformatics. Differentially expressed genes (DEGs) and microRNAs (DEMs) were obtained by R software. The protein–protein interaction (PPI) networks of the DEGs were performed from the STRING database and further visualized by Cytoscape software. A total of 83 DEGs and 14 DEMs were screened from the microarray expression profile datasets. The miRNAs validated to be associated with cervical cancer were obtained using HMDD online website and the target genes of DEMs were identified using the miRWalk2.0 online database. ESR1, PPP1R3C, NSG1, and TMPRSS11D were the gene targets of hsa-miR-21; the targets of hsa-miR-16 were GYS2, ENDOU, and KLF4. These targets were all downregulated in cervical cancer. Finally, we verified the expression of those targets in cervical tissues from TCGA and GTEx databases and analyzed their relationship with survival of cervical cancer patients. In the end, the expression of key genes in cervical cancer tissues was verified via experiment method, we found KLF4 and ESR1 were downregulated in tumor tissues.

Conclusion: This study indicates that KLF4 and ESR1 are downregulated by the upregulated miR21 and miRNA16 in cervical cancer, respectively, using bioinformatics analysis, and the lower expression of KLF4 and ESR1 is closely related to the poor prognosis. They might be of clinical significance for the diagnosis and prognosis of cervical cancer, and provide effective targets for the treatment of cervical cancer.

miR‑505 inhibits cell growth and EMT by targeting MAP3K3 through the AKT‑NFκB pathway in NSCLC cells

MicroRNAs (miRNAs) are short non-coding RNAs, which generally regulate gene expression at the post-transcriptional level. Dysregulation of miRNAs has been reported in numerous cancer types, including lung cancer. In the present study, the role of miR-505 in non-small cell lung cancer (NSCLC) cells was investigated. miR-505 served a tumor suppressor role in NSCLC cells. By reverse transcriptase-quantitative polymerase chain reaction detection, it was demonstrated that miR-505 was downregulated in NSCLC tissues and cell lines, which is negatively associated with large tumor size, Tumor-Node-Metastasis stage and distant metastasis in patients with NSCLC. Functional studies revealed that miR-505 inhibited cell proliferation, migration, invasion and epithelial-mesenchymal transition progress in vitro and tumor growth in vivo. Mechanically, mitogen-activated protein kinase kinase kinase 3 (MAP3K3) was identified as a direct target of miR-505 by binding to its 3′untranslated region and demonstrated to mediate the tumor suppressor roles of miR-505 in NSCLC cells. The effect of miR-505 on the activation of AKT/nuclear factor-κB (NFκB) pathway, which was downstream targets of MAP3K3, was further analyzed by western blot analysis and immunofluorescence analyses. The data demonstrated the inhibition of the AKT/NFκB pathway upon overexpressing miR-505 and the activation of AKT/NFκB pathway upon silencing miR-505. Collectively, the data revealed the novel role and target of miR-505 in NSCLC cells, which may provide novel insights regarding its role in the carcinogenesis of NSCLC and its potential values for clinical applications.