miR-150-5p promotes the proliferation and epithelial-mesenchymal transition of cervical carcinoma cells via targeting SRCIN1

MicroRNA-150-5p-mediated Inhibition of Cell Proliferation, G1/S Transition, and Migration in Bladder Cancer through Targeting NEDD4-binding Protein 2-like 1 Gene

MicroRNA-150-5p (miR-150-5p) has been implicated in the progression of several cancer types, yet its specific functional role and regulatory mechanisms in bladder cancer (BC) remain largely unexplored. Our study revealed significant downregulation of miR-150-5p and upregulation of NEDD4-binding protein 2-like 1 gene (N4BP2L1) in BC tissues compared to controls using quantitative real-time polymerase chain reaction and western blot analysis, respectively. Reduced miR-150-5p expression correlated with advanced tumor stage and lymph node metastasis, while increased N4BP2L1 levels were associated with larger tumor size by the Chi-square test. Functionally, miR-150-5p exerted significant inhibitory effects on BC cell proliferation, migration, inducing G0/G1 phase arrest, and apoptosis. We confirmed N4BP2L1 as a direct target of miR-150-5p in BC cells using luciferase reporter assay. Crucially, N4BP2L1 knockdown mimicked, while overexpression counteracted the inhibitory impacts of miR-150-5p on BC cell proliferation, migration, and invasion. In addition, N4BP2L1 overexpression reversed miR-150-5p-induced alterations in CDK4, Cyclin D1, Bcl-2, PCNA, Ki-67, N-cadherin, Bad, and E-cadherin levels in BC cells. Based on these results, it can be inferred that the miR-150-5p/N4BP2L1 axis might constitute a promising candidate for therapeutic targeting in the treatment of BC.

HPV16 E6 promoting cervical cancer progression through down-regulation of miR-320a to increase TOP2A expression

BACKGROUND

Cervical cancer (CC) has become the fourth most common cancer worldwide and it is mainly caused by the infection of human papillomavirus (HPV), especially high-risk HPV16. Aberrant miRNA expression in CC is closely related to HPV16 infection, and the regulation of HPV16 E6 expression can affect a variety of miRNA expression. This study aims to exploring the miRNAs involved in E6 regulation in CC.

METHODS

Our study screened differentially expressed miRNAs in cervical cells of HPV16 infected and uninfected cervical cancer patients by analyzing the GSE81137 dataset of the gene expression omnibus database (GEO), and identified miR-320a that plays an anti-tumor role and is associated with good prognosis of cervical cancer. Explore the effect of HPV16 E6 on the expression of miR-320a in cervical cancer, and verify whether HPV16 E6 regulates the downstream target gene TOP2A expression through miR-320a, thereby affecting cervical cancer cell proliferation, apoptosis, migration, invasion, and EMT in vitro and in vivo.

RESULTS

The bioinformatic methods selected the miR-320a, which was differentially expressed in cervical cells from HPV16-infected patients compared to uninfected patients. We further demonstrated that miR-320a level was regulated by HPV16 E6, which promoted the CC cell proliferation, migration, invasion, and inhibited apoptosis. In addition, we predicted the downstream target genes of miR-320a and confirmed that TOP2A was one of its targeting proteins. Moreover, HPV16 E6 promoted the TOP2A expression in CC cells through down-regulating miR-320a, leading to promoting CC development.

CONCLUSIONS

We confirmed that HPV16 E6 promoted the TOP2A expression through down-regulation of miR-320a, thus promoting CC development, and the HPV16 E6/miR-320a/TOP2A axis may perform as a potential target for CC treatment.

Diverse activity of miR-150 in Tumor development: shedding light on the potential mechanisms

There is a growing interest to understand the role and mechanism of action of microRNAs (miRNAs) in cancer. The miRNAs are defined as short non-coding RNAs (18-22nt) that regulate fundamental cellular processes through mRNA targeting in multicellular organisms. The miR-150 is one of the miRNAs that have a crucial role during tumor cell progression and metastasis. Based on accumulated evidence, miR-150 acts as a double-edged sword in malignant cells, leading to either tumor-suppressive or oncogenic function. An overview of miR-150 function and interactions with regulatory and signaling pathways helps to elucidate these inconsistent effects in metastatic cells. Aberrant levels of miR-150 are detectable in metastatic cells that are closely related to cancer cell migration, invasion, and angiogenesis. The ability of miR-150 in regulating of epithelial-mesenchymal transition (EMT) process, a critical stage in tumor cell migration and metastasis, has been highlighted. Depending on the cancer cells type and gene expression profile, levels of miR-150 and potential target genes in the fundamental cellular process can be different. Interaction between miR-150 and other non-coding RNAs, such as long non-coding RNAs and circular RNAs, can have a profound effect on the behavior of metastatic cells. MiR-150 plays a significant role in cancer metastasis and may be a potential therapeutic target for preventing or treating metastatic cancer.

Downregulated miR-150-5p in the Tissue of Nasopharyngeal Carcinoma

The clinical significance and potential targets of miR-150-5p have not been elucidated in nasopharyngeal carcinoma (NPC). The pooled analysis based on 539 NPC samples and 75 non-NPC nasopharyngeal samples demonstrated that the expression of miR-150-5p was down-regulated in NPC, with the area under the curve being 0.89 and the standardized mean difference being -0.66. Subsequently, we further screened the differentially expressed genes (DEGs) of 14 datasets, including 312 NPC samples and 70 non-NPC nasopharyngeal samples. After the DEGs were narrowed down with the predicted targets from the miRWalk database, 1316 prospective target genes of miR-150-5p were identified. The enrichment analysis suggested that "pathways in cancer" was the most significant pathway. Finally, six hub genes of "pathways in cancer", including EGFR, TP53, HRAS, CCND1, CDH1, and FGF2, were screened out through the STRING database. In conclusion, the down-regulation of miR-150-5p modulates the tumorigenesis and progression of NPC.

miR-657 Targets SRCIN1 via the Slug Pathway to Promote NSCLC Tumor Growth and EMT Induction

Background

MicroRNA- (miR-) 657 has been shown to regulate immunological and inflammatory activity, and it has also been defined to be dysregulated in both non-small-cell lung cancer (NSCLC) and hepatocellular carcinoma. The mechanistic role whereby miR-657 influences NSCLC progression, however, has yet to be clarified.

Methods

miR-657 and SRCIN1 expression levels were assessed via qPCR in the cell lines and tissues of NSCLC. Besides, correlations between the levels of miR-657 and NSCLC patient pathological characteristics were examined, and the Kaplan-Meier approach was employed for the evaluation of the prognostic utility of miR-657 in these patients. Moreover, the Pearson correlation analyses and dual-luciferase reporter assessments were used for detecting interactive relationships between miR-657 and SRCIN1. In addition, CCK-8, EdU, and Transwell assessments were employed for the appraisal of the ability of miR-657/SRCIN1 to regulate NSCLC cell proliferation and invasion. Western blotting was employed for the assessment of the levels of NSCLC cell proteins associated with the epithelial-mesenchymal transition (EMT) that were influenced by miR-657. The nude mice xenograft tumor model is established to observe the effect of miR-657 on NSCLC growth in vivo.

Results

NSCLC patient tissues and cell lines exhibited upregulated miR-657 expression that was closely related to tumor differentiation, lymphoid metastasis, and TNM stage. High levels of miR-657 were predictive of a poorer NSCLC patient prognosis, and overexpressing miR-657 resulted in the more rapid growth of NCI-H1650 and A549 cells, with a concomitant increase in their invasion. In addition, miR-657 overexpression raised the levels of Slug, N-cadherin, and Vimentin in these two cell lines while promoting E-cadherin downregulation. Dual-luciferase reporter assays confirmed that miR-657 was capable of binding to the SRCIN1 gene, and SRCIN1 expression levels were negatively associated with those of miR-657, indicating that it acts as a negative regulator of this gene. Knocking down SRCIN1 was capable to reverse the influences of miR-657 inhibitor treatment on NSCLC cell behavior. Finally, in vivo studies showed that miR-657 promoted NSCLC cell growth.

Conclusion

The obtained findings illuminate that miR-657 can promote the growth of tumors and the induction of the EMT in NSCLC cells by targeting SRCIN1 expression and modulating Slug pathway activation, highlighting this pathway as a promising therapeutic target in cases suffering from NSCLC.

MiR-150-5p Overexpression in Triple-Negative Breast Cancer Contributes to the In Vitro Aggressiveness of This Breast Cancer Subtype

Simple Summary

Triple-negative breast cancer (TNBC) is a clinically aggressive type of breast cancer. MicroRNAs (miRNAs) are small molecules that regulate the expression of genes involved in tumor cell signaling. The miR-150-5p is frequently deregulated in cancer, with expression and mode of action varying according to the cancer type. In this study, we investigated the expression levels of miR-150-5p in TNBC, its association with clinical and pathological features of patients, and its role in modulating TNBC cell proliferation, migration, and drug resistance. Our results suggest that miR-150-5p is highly expressed in TNBC and that miR-150-5p expression levels are associated with tumor grade, patient survival, and ethnicity. Our findings also indicate that miR-150-5p contributes to the aggressive phenotypes of TNBC cells in vitro.

Abstract

MiR-150-5p is frequently deregulated in cancer, with expression and mode of action varying according to the tumor type. Here, we investigated the expression levels and role of miR-150-5p in the aggressive breast cancer subtype triple-negative breast cancer (TNBC). MiR-150-5p expression levels were analyzed in tissue samples from 113 patients with invasive breast cancer (56 TNBC and 57 non-TNBC) and 41 adjacent non-tumor tissues (ANT). Overexpression of miR-150-5p was observed in tumor tissues compared with ANT tissues and in TNBC compared with non-TNBC tissues. MiR-150-5p expression levels were significantly associated with high tumor grades and the Caucasian ethnicity. Interestingly, high miR-150-5p levels were associated with prolonged overall survival. Manipulation of miR-150-5p expression in TNBC cells modulated cell proliferation, clonogenicity, migration, and drug resistance. Manipulation of miR-150-5p expression also resulted in altered expression of its mRNA targets, including epithelial-to-mesenchymal transition markers, MYB, and members of the SRC pathway. These findings suggest that miR-150-5p is overexpressed in TNBC and contributes to the aggressiveness of TNBC cells in vitro.

The Role of MiRNA in Cancer: Pathogenesis, Diagnosis, and Treatment

Cancer is also determined by the alterations of oncogenes and tumor suppressor genes. These gene expressions can be regulated by microRNAs (miRNA). At this point, researchers focus on addressing two main questions: "How are oncogenes and/or tumor suppressor genes regulated by miRNAs?" and "Which other mechanisms in cancer cells are regulated by miRNAs?" In this work we focus on gathering the publications answering these questions. The expression of miRNAs is affected by amplification, deletion or mutation. These processes are controlled by oncogenes and tumor suppressor genes, which regulate different mechanisms of cancer initiation and progression including cell proliferation, cell growth, apoptosis, DNA repair, invasion, angiogenesis, metastasis, drug resistance, metabolic regulation, and immune response regulation in cancer cells. In addition, profiling of miRNA is an important step in developing a new therapeutic approach for cancer.

MicroRNAs in Valvular Heart Diseases: Biological Regulators, Prognostic Markers and Therapeutical Targets

miRNAs have recently attracted investigators’ interest as regulators of valvular diseases pathogenesis, diagnostic biomarkers, and therapeutical targets. Evidence from in-vivo and in-vitro studies demonstrated stimulatory or inhibitory roles in mitral valve prolapse development, aortic leaflet fusion, and calcification pathways, specifically osteoblastic differentiation and transcription factors modulation. Tissue expression assessment and comparison between physiological and pathological phenotypes of different disease entities, including mitral valve prolapse and mitral chordae tendineae rupture, emerged as the best strategies to address miRNAs over or under-representation and thus, their impact on pathogeneses. In this review, we discuss the fundamental intra- and intercellular signals regulated by miRNAs leading to defects in mitral and aortic valves, congenital heart diseases, and the possible therapeutic strategies targeting them. These miRNAs inhibitors are comprised of antisense oligonucleotides and sponge vectors. The miRNA mimics, miRNA expression vectors, and small molecules are instead possible practical strategies to increase specific miRNA activity. Advantages and technical limitations of these new drugs, including instability and complex pharmacokinetics, are also presented. Novel delivery strategies, such as nanoparticles and liposomes, are described to improve knowledge on future personalized treatment directions.

MicroRNAs in Epithelial-Mesenchymal Transition Process of Cancer: Potential Targets for Chemotherapy

In the last decades, a kind of small non-coding RNA molecules, called as microRNAs, has been applied as negative regulators in various types of cancer treatment through down-regulation of their targets. More recent studies exert that microRNAs play a critical role in the EMT process of cancer, promoting or inhibiting EMT progression. Interestingly, accumulating evidence suggests that pure compounds from natural plants could modulate deregulated microRNAs to inhibit EMT, resulting in the inhibition of cancer development. This small essay is on the purpose of demonstrating the significance and function of microRNAs in the EMT process as oncogenes and tumor suppressor genes according to studies mainly conducted in the last four years, providing evidence of efficient target therapy. The review also summarizes the drug candidates with the ability to restrain EMT in cancer through microRNA regulation.

The role of HPV-induced epigenetic changes in cervical carcinogenesis (Review)

Cervical cancer is associated with infection by certain types of human papillomaviruses (HPVs), and this affects women worldwide. Despite the improvements in prevention and cure of HPV-induced cervical cancer, it remains the second most common type of cancer in women in the least developed regions of the world. Epigenetic modifications are stable long-term changes that occur in the DNA, and are part of a natural evolutionary process of necessary adaptations to the environment. They do not result in changes in the DNA sequence, but do affect gene expression and genomic stability. Epigenetic changes are important in several biological processes. The effects of the environment on gene expression can contribute to the development of numerous diseases. Epigenetic modifications may serve a critical role in cancer cells, by silencing tumor suppressor genes, activating oncogenes, and exacerbating defects in DNA repair mechanisms. Although cervical cancer is directly related to a persistent high-risk HPV infection, several epigenetic changes have been identified in both the viral DNA and the genome of the infected cells: DNA methylation, histone modification and gene silencing by non-coding RNAs, which initiate and sustain epigenetic changes. In the present review, recent advances in the role of epigenetic changes in cervical cancer are summarized.

Putative Circulating MicroRNAs Are Able to Identify Patients with Mitral Valve Prolapse and Severe Regurgitation

Mitral valve prolapse (MVP) associated with severe mitral regurgitation is a debilitating disease with no pharmacological therapies available. MicroRNAs (miRNA) represent an emerging class of circulating biomarkers that have never been evaluated in MVP human plasma. Our aim was to identify a possible miRNA signature that is able to discriminate MVP patients from healthy subjects (CTRL) and to shed light on the putative altered molecular pathways in MVP. We evaluated a plasma miRNA profile using Human MicroRNA Card A followed by real-time PCR validations. In addition, to assess the discriminative power of selected miRNAs, we implemented a machine learning analysis. MiRNA profiling and validations revealed that miR-140-3p, 150-5p, 210-3p, 451a, and 487a-3p were significantly upregulated in MVP, while miR-223-3p, 323a-3p, 340-5p, and 361-5p were significantly downregulated in MVP compared to CTRL (p ≤ 0.01). Functional analysis identified several biological processes possible linked to MVP. In addition, machine learning analysis correctly classified MVP patients from CTRL with high accuracy (0.93) and an area under the receiving operator characteristic curve (AUC) of 0.97. To the best of our knowledge, this is the first study performed on human plasma, showing a strong association between miRNAs and MVP. Thus, a circulating molecular signature could be used as a first-line, fast, and cheap screening tool for MVP identification.

MCM3AP-AS1 promotes cisplatin resistance in gastric cancer cells via the miR-138/FOXC1 axis

The dysregulation of long non-coding RNAs (lncRNAs) serves a pivotal role in the pathogenesis and development of multiple types of human cancer, including gastric cancer (GC). MCM3AP-antisense 1 (MCM3AP-AS1) has been reported to function as a tumor promoter in various types of cancer. However, the biological function of MCM3AP-AS1 in the resistance of GC cells to cisplatin (CDDP) remains to be elucidated. The present study aimed to elucidate the mechanisms of MCM3AP-AS1 in the resistance of GC cells to CDDP. The expression levels of MCM3AP-AS1, miR-138 and FOXC1 were measured via reverse transcription-quantitative PCR. In addition, cell viability, migration and invasion were assessed via the Cell Counting Kit-8, wound healing and transwell assays, respectively. The interaction between genes was confirmed via the dual-luciferase reporter and pull-down assays. Western blot analysis was performed to detect FOXC1 protein expression. In the present study, it was demonstrated that MCM3AP-AS1 expression was upregulated in CDDP-resistant GC cells and that MCM3AP-AS1-knockdown suppressed CDDP resistance in GC cells. Moreover, the examination of the molecular mechanism indicated that MCM3AP-AS1 upregulated FOXC1 expression by sponging microRNA (miR)-138. Additionally, it was identified that the overexpression of FOXC1 abolished MCM3AP-AS1-knockdown- or miR-138 mimic-mediated inhibitory effects on CDDP resistance in GC cells. In conclusion, the present findings suggested that MCM3AP-AS1 enhanced CDDP resistance by sponging miR-138 to upregulate FOXC1 expression, indicating that MCM3AP-AS1 may be a novel promising biomarker for the diagnosis and treatment of patients with GC.

Effect of miRNA-200b on the proliferation and apoptosis of cervical cancer cells by targeting RhoA

Objective

This article aims to investigate the effect of miRNA-200b on the proliferation and apoptosis of cervical cancer cells by targeting RhoA.

Methods

HeLa cells of cervical cancer were divided into five groups: blank control group, negative control group (miRNA-200b mimic NC), miRNA-200b mimic group, RhoA-negative control group, and RhoA overexpression group. Cells were collected 48 h after transfection. The expression levels of miRNA-200b were detected by RT-PCR. Target relationship between miRNA-200b and RhoA was verified by the dual-luciferase reporter assay. RhoA mRNA and protein expression were detected by western blot and RT-PCR methods. Flow cytometry was used to detect the apoptosis of cells in each group, and the CCK8 method was used to detect the proliferation of cells in each group. The mRNA and protein expression of Bax and cyclin D1 were detected by RT-PCR and western blot.

Results

The results of the dual luciferase reporter assay showed that RhoA was the target gene of microRNA 200b. Compared with the blank control group and the miRNA-200b mimic-NC group, the proportion of apoptotic cells increased significantly in the miRNA-200b mimic group, and the proliferation of cells was inhibited (P < 0.05). After overexpression of RhoA, the percentage of apoptotic cells decreased and the ability of cell proliferation increased significantly (P < 0.05).

Conclusion

miRNA-200b can inhibit the proliferation and promote the apoptosis of cervical cancer cells by targeting the RhoA gene.

HPV16 E6 regulates the proliferation, invasion, and apoptosis of cervical cancer cells by downregulating miR-504

BACKGROUND

Human papillomavirus (HPV) 16 infection is a necessary condition for the pathogenesis and development of cervical cancer. The E6 protein is expressed by the HPV16 E6 gene and promotes malignant phenotype transformation, which is an important mechanism for the occurrence and development of cervical cancer. MicroRNA-504 (miR-504) has been reported as an oncogene or tumor suppressor gene; the expression of miR-504 in cervical cancer has been found to be negatively correlated with HPV infection. However, the relationship between HPV16 E6 and miR-504 and the role of miR-504 in cervical cancer are not clear. In the current study, we observed the effect of HPV16 E6 on the expression of miR-504 in cervical cancer cells, and analyzed whether HPV16 E6 affects proliferation, invasion, and apoptosis in cervical cancer cells by regulating the expression of miR-504.

METHODS

Cervical cancer cells (SiHa) were divided into four groups: the empty vector group, E6 overexpression group, E6 overexpression + miR-NC group, and E6 overexpression+miR-504 group. The expressions levels of HPV16 E6 mRNA and miR-504 were detected by real-time polymerase chain reaction (PCR), and the expression level of HPV16 E6 protein was detected by Western blot. Cell proliferation, invasion, and apoptosis were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, Tastelessly, and flow cytometry, respectively.

RESULTS

The expression level of miR-504 was significantly decreased in E6 overexpression cells compared to the control cells (P<0.05); the overexpression of miR-504 with miR-504 mimic significantly reversed the downregulation of miR-504 in E6 overexpression SiHa cells (P<0.05). MTT and Transwell assays showed that the overexpression of E6 significantly increased proliferation and invasion of SiHa cells (P<0.05). The overexpression of miR-504 reversed the role of HPV16 E6 on the proliferation and invasion in E6 overexpression SiHa cells, and the difference was statistically significant (P<0.05). Further analysis showed that the overexpression of E6 significantly reduced apoptosis of SiHa cells (P<0.05). The overexpression of miR-504 reversed the role of HPV16 E6 on apoptosis in E6 overexpression SiHa cells, and the difference was statistically significant (P<0.05).

CONCLUSIONS

HPV16 E6 may promote the proliferation and invasion, and inhibit the apoptosis, of cervical cancer SiHa cells by downregulating miR-504 expression.

miR-587 promotes cervical cancer by repressing interferon regulatory factor 6

BACKGROUND

Interferon regulatory factor 6 (IRF6) exhibits tumor-suppressive functions in several cancer types. In the present study, the antitumor properties and related pathway mechanism of IRF6 were investigated in cervical cancer.

METHODS

Forty-one pairs of cervical cancer specimens and para-carcinoma tissues were collected to evaluate IRF6 expression using immunohistochemical staining and miR-587. The effects of miR-587 and IRF6 on cervical cancer cell growth were explored by MTT assays and in a HeLa tumor xenograft mouse model. The migration and invasion of cervical cancer cells were monitored using transwell assays.

RESULTS

IRF6 expression in cervical cancer specimens and cell lines was significantly reduced compared to that in the corresponding control group. In addition, IRF6 expression was negatively correlated with miR-587 in cervical cancer tissues. Bioinformatics algorithms and luciferase assays revealed that IRF6 is a potential target of miR-587, and miR-587 mimic transfection led to a significant repression of IRF6 protein levels in cervical cancer cells. We also discovered that the antineoplastic properties of IRF6 could be reversed by overexpressing miR-587 in cervical cancer cells. The up-regulation of miR-587 was correlated with poor overall survival in cervical cancer. In an in vivo experiment, miR-587 silencing induced HeLa tumor growth inhibition, which was associated with the up-regulation of IRF6 protein in the tumor.

CONCLUSIONS

miR-587 post-transcriptionally represses IRF6 protein expression to abrogate the antineoplastic activity of IRF6. The miR-587/IRF6 signaling pathway plays a crucial role in the progression of cervical cancer and serves as a potential therapeutic target for the treatment of cervical cancer.

The p140Cap adaptor protein as a molecular hub to block cancer aggressiveness

The p140Cap adaptor protein is a scaffold molecule encoded by the SRCIN1 gene, which is physiologically expressed in several epithelial tissues and in the neurons. However, p140Cap is also strongly expressed in a significant subset of cancers including breast cancer and neuroblastoma. Notably, cancer patients with high p140Cap expression in their primary tumors have a lower probability of developing a distant event and ERBB2-positive breast cancer sufferers show better survival. In neuroblastoma patients, SRCIN1 mRNA levels represent an independent risk factor, which is inversely correlated to disease aggressiveness. Consistent with clinical data, SRCIN1 gain or loss of function mouse models demonstrated that p140Cap may affect tumor growth and metastasis formation by controlling the signaling pathways involved in tumorigenesis and metastatic features. This study reviews data showing the relevance of SRCIN1/p140Cap in cancer patients, the impact of SRCIN1 status on p140Cap expression, the specific mechanisms through which p140Cap can limit cancer progression, the molecular functions regulated by p140Cap, along with the p140Cap interactome, to unveil its key role for patient stratification in clinics.

MicroRNA-150 suppresses p27Kip1 expression and promotes cell proliferation in HeLa human cervical cancer cells

MicroRNAs (miRNAs) exert critical roles in the majority of biological and pathological processes. Recent studies have associated miR-150 with a number of different cancer types. However, little is known about miR-150 targets in cervical cancer. In the present study, the HeLa human cervical cancer cell line was transfected with hsa-miR-150-5p mimics, hsa-miR-150-5p inhibitors or miRNA controls. miR-150 was predicted to bind the 3'untranslated region (3'UTR) of the CDKN1B gene, which encodes the cyclin-dependent kinase inhibitor 1B (p27^Kip1). The direct binding between miR-150 and the 3'UTR of CDKN1B was confirmed using dual-luciferase reporter assays. The effects of miR-150 on CDKN1B mRNA expression, p27^Kip1 protein expression, cell cycle and cell proliferation were determined using reverse-transcription quantitative PCR, western blot analysis, flow cytometry and WST-8 assays, respectively. miR-150 was demonstrated to directly target the 3'UTR of CDKN1B in transfected HeLa cells. The expression of CDKN1B mRNA and p27^Kip1 protein was reduced by miR-150 mimics, and increased by miR-150 inhibitors. Moreover, the overexpression of miR-150 promoted cell cycle progression from the G0/G1 to the S phase and led to a significant increase in HeLa cell proliferation. The results of the present study indicated that miR-150 promotes HeLa cell cycle progression and proliferation via the suppression of p27^Kip1 expression.

Higher expression of miR-150-5p promotes tumorigenesis by suppressing LKB1 in non-small cell lung cancer

Lung cancer is one of the most malignant tumors that can form in the human. MicroRNAs (MiRNAs) play significant role in tumor progression. Human lung cancer tissues and cell lines were used to determine miR-150-5p respectively, and Liver Kinase B1 (LKB1) expression using quantitative real-time PCR (qRT-PCR). The data analysis website Kaplan-Meier Plotter (database obtained from The Cancer Genome Atlas) was used to perform a survival analysis with LKB1 levels. Using the appropriate assays, the function of miR-150-5p was also detected in cellular proliferation, migration and cell apoptosis as well as cell cycle. Results revealed that miR-150-5p was upregulated in non-small cell lung cancer (NSCLC) tissue and cell lines. In NSCLC, miR-150-5p promoted cellular proliferation and migration, but decreased cellular apoptosis. Conversely, miR-150-5p inhibition suppressed cellular growth. These results further revealed a network of cellular signaling for miR-150-5p to target LKB1. Ectopic expression of LKB1 can mitigate the tumor-promoting function of miR-150-5p. Collectively, these results indicated that miR-150-5p may promote lung cancer by inhibiting the suppressor gene LKB1 in NSCLC.

MicroRNA-138 inhibits tumor growth and enhances chemosensitivity in human cervical cancer by targeting H2AX

MicroRNA-138 (miR-138) acts as a key regulator in the modulation of carcinogenesis in numerous tumor types. Chemoresistance is common and relevant to the failure of multiple treatment strategies for cervical cancer. However, the biological role of miR-138 in the progression and chemosensitivity of cervical cancer is still unclear. The present study aimed to investigate the expression, function and mechanism of miR-138 in cervical cancer. An miR-138 mimic, inhibitor and negative control were transfected into SiHa and C33A cells. The expression of miR-138 and its target were assessed by reverse transcription-PCR, western blotting and immunohistochemistry. The functional significance of miR-138 in tumor progression and chemosensitivity to cisplatin in vitro was examined by Cell Counting Kit-8, flow cytometry, wound healing and Transwell assays. A tumor xenograft model was used to validate the effects in vivo. These results demonstrated that miR-138 was significantly downregulated in cervical cancer cells. Overexpression of miR-138 suppressed cervical cancer cell proliferation, invasion, increased apoptosis and enhanced chemotherapy sensitivity in vivo and in vitro. Furthermore, bioinformatics analysis and dual luciferase reporter assays demonstrated that H2AX served as a target for miR-138, and the rescue experiment revealed that H2AX was a functional target of miR-138. The protective effects of miR-138 overexpression were dependent on H2AX. This study provides evidence that miR-138/H2AX may be a novel therapeutic target in cervical cancer.