MiR-126-3p inhibits ovarian cancer proliferation and invasion via targeting PLXNB2

Ovarian cancer is one of the leading malignancies in women and the 5-year survival rate of ovarian cancer still remains poor. In the present study, we aimed to investigate the interaction between the miR-126-3p and PLXNB2 in the progression of ovarian cancer. The qRT-PCR data revealed a reduction of miR-126-3p level in ovarian cancer tissues comparing to the adjacent normal tissues. Over-expression of miR-126-3p in ovarian cancer cells suppressed cell proliferation and invasion and the phosphorylation of AKT and ERK1/2. The cell cycle assay results showed that the over-expression of miR-126-3p induced cells in G1-phase and reduced cells in S-phase. We further performed bioinformatics analysis and luciferase assay to investigate the relationship between miR-126-3p and PLXNB2 in ovarian cancer cells. The results of TargetScan suggested that PLXNB2 is a direct target of miR-126-3p in ovarian cancer cells, and luciferase assay confirmed bioinformatics prediction. Knocking down of PLXNB2 with PLXNB2 siRNA results in repressed ovarian cancer cell proliferation and invasion, and decreased phosphorylation of AKT and ERK1/2, which is similar to the effect of over-expression of miR-126-3p in OC cells. The synergistic effect of combination of miR-126-3p over-expression and PLXNB2 down-regulation on the cell growth viability, cell colony, and cell invasion was also identified. All these findings indicated that miR-126-3p is involved in the progression of ovarian cancer via direct regulating PLXNB2.     

Upregulation of miR-582-5p regulates cell proliferation and apoptosis by targeting AKT3 in human endometrial carcinoma

The human endometrial carcinoma is one of the most common female malignancies, and there is an urgent requirement to explore new therapeutic strategies. There is accumulating evidence that microRNAs (miRNAs) can serve as potential diagnostic and prognostic biomarkers for various types of cancer, but the significance of miR-582-5p still remains largely unknown in the endometrial carcinoma. The aims of this study were to understand and identify the influence of miR-582-5p on the proliferation and apoptosis of human endometrial carcinoma and its relevant mechanism. First, quantitative real-time PCR (qRT-PCR) was used to detect miR-582-5p and AKT3 expression in human tissue samples and cells. Then, CyQuant assay and 2D colony assay were employed to evaluate cell proliferation. Western blotting was used to determine protein expression. Subsequently, the luciferase reporter assay was used to identify the target of miR-582-5p. Finally, Annexin V assay was used to detect cell apoptosis. We found that miR-582-5p expression was significantly decreased in human endometrial carcinoma tissues, and miR-582-5p upregulation in human endometrial carcinoma cells inhibit cell proliferation and promote apoptosis. Moreover, AKT3 was validated as a target of miR-582-5p and AKT3 expression was inversely correlated with miR-582-5p expression. Besides, AKT3 upregulation efficiently abrogates the effect of miR-582-5p on the cells. These results demonstrated that miR-582-5p regulates cell proliferation and apoptosis in human endometrial carcinoma via AKT3. Thus, miR-582-5p represents a potential therapeutic target in human endometrial carcinoma meriting further investigation.     

MicroRNA-590-3P suppresses cell survival and triggers breast cancer cell apoptosis via targeting sirtuin-1 and deacetylation of p53

Downregulation of microRNA-590-3p (miR-590-3p) is a frequently occurring, nonphysiological event which is observed in several human cancers, especially breast cancer. However, the significance of miR-590-3p still remain unclear in the progression of this disease. This study explored the role of miR-590-3p in apoptosis of breast cancer cells. Gene expression of miR-590-3p, Sirtuin-1 (SIRT1), Bcl-2 associated X protein (BAX), and p21 was evaluated with real-time polymerase chain reaction (PCR) and SIRT1 protein expression was assessed by Western blot analysis in breast cancer cell lines. Bioinformatics analysis and luciferase reporter assay were used to evaluate targeting of SIRT1 messenger RNA (mRNA) by miR-590-3p. Cells were transfected with miR-590-3p mimic and inhibitor and their effects on the expression and activity of SIRT1 were evaluated. The effects of miR-590-3p upregulation on the acetylation of p53 as well as cell viability and apoptosis were assessed by Western blot analysis, WST-1 assay, and flow cytometry, respectively. miR-590-3p expression was considerably downregulated in breast cancer cells which was accompanied by upregulation of SIRT1 expression. SIRT1 was recognized as a direct target for miR-590-3p in breast cancer cells and its protein expression and activity was dramatically inhibited by the miR-590-3p. In addition, there was an increase in p53 and its acetylated form that ultimately led to upregulation of BAX and p21 expression, suppression of cell survival, and considerable induction of apoptosis in breast cancer cells. These findings suggest that miR-590-3p exerts tumor-suppressing effects through targeting SIRT1 in breast cancer cells, which makes it a potential therapeutic target for developing more efficient treatments for breast cancer.     

The combined restoration of miR-424-5p and miR-142-3p effectively inhibits MCF-7 breast cancer cell line via modulating apoptosis,proliferation, colony formation,cell cycle and autophagy

Background

The combined restoration of tumor-suppressive microRNAs (miRs) has been identified as a promising approach for inhibiting breast cancer development. This study investigated the effect of the combined restoration of miR-424-5p and miR-142-3p on MCF-7 cells and compared the efficacy of the combined therapy with the monotherapies with miR-424-5p and miR-142-3p.

Methods

After transfection of miR-424-5p and miR-142-3p mimics into MCF-7 cells in the combined and separated manner, the proliferation of tumoral cells was assessed by the MTT assay. Also, the apoptosis, autophagy, and cell cycle of the cells were analyzed by flow cytometry. Western blot and qRT-PCR were used to study the expression levels of c-Myc, Bcl-2, Bax, STAT-3, Oct-3, and Beclin-1.

Results

Our results have demonstrated that the combined restoration of miR-424-5p and miR-142-3p is more effective in inhibiting tumor proliferation via upregulating Bax and Beclin-1 and downregulating Bcl-2 and c-Myc. Besides, the combined therapy has arrested the cell cycle in the sub-G1 and G2 phases and has suppressed the clonogenicity via downregulating STAT-3 and Oct-3, respectively.

Conclusion

The combined restoration of miR-424-5p and miR-142-3p is more effective in inhibiting MCF-7 breast cancer development than monotherapies with miR-424-5p and miR-142-3p.

     

Cancer-associated fibroblast-derived exosomal microRNA-24-3p enhances colon cancer cell resistance to MTX by down-regulating CDX2/HEPH axis

MicroRNA-24-3p (miR-24-3p) has been implicated as a key promoter of chemotherapy resistance in numerous cancers. Meanwhile, cancer-associated fibroblasts (CAFs) can secret exosomes to transfer miRNAs, which mediate tumour development. However, little is known regarding the molecular mechanism of CAF-derived exosomal miR-24-3p in colon cancer (CC). Hence, this study intended to characterize the functional relevance of CAF-derived exosomal miR-24-3p in CC cell resistance to methotrexate (MTX). We identified differentially expressed HEPH, CDX2 and miR-24-3p in CC through bioinformatics analyses, and validated their expression in CC tissues and cells. The relationship among HEPH, CDX2 and miR-24-3p was verified using ChIP and dual-luciferase reporter gene assays. Exosomes were isolated from miR-24-3p inhibitor–treated CAFs (CAFs-exo/miR-24-3p inhibitor), which were used in combination with gain-of-function and loss-of-function experiments and MTX treatment. CCK-8, flow cytometry and colony formation assays were conducted to determine cell viability, apoptosis and colony formation, respectively. Based on the findings, CC tissues and cells presented with high expression of miR-24-3p and low expression of HEPH and CDX2. CDX2 was a target gene of miR-24-3p and could up-regulate HEPH. Under MTX treatment, overexpressed CDX2 or HEPH and down-regulated miR-24-3p reduced cell viability and colony formation and elevated cell apoptosis. Furthermore, miR-24-3p was transferred into CC cells via CAF-derived exosomes. CAF-derived exosomal miR-24-3p inhibitor diminished cell viability and colony formation and increased cell apoptosis in vitro and inhibited tumour growth in vivo under MTX treatment. Altogether, CAF-derived exosomal miR-24-3p accelerated resistance of CC cells to MTX by down-regulating CDX2/HEPH axis.     

应用活细胞RNA检测纳米技术检测乳腺上皮细胞MCF-10A及乳腺癌细胞MCF-7中miR-142-3p的表达

传统的核酸检测技术如放射性核素、荧光、化学修饰的探针以及核酸扩增等技术无法检测活细胞中核酸的表达量。而活细胞RNA纳米检测技术和传统的检测技术相比,利用纳米金颗粒为探针能对活细胞进行检测,实验步骤更为简单,可以在自然的、无扩增的条件下观察RNA,这可真实地反应基因表达与表型之间的关系。miRNA是一类非编码RNA,其长度为20～24个碱基,在生命活动中起重要的作用。本文应用活细胞RNA检测纳米技术结合荧光定量PCR分别检测正常的乳腺上皮细胞系及乳腺上皮癌细胞系中内源性miR-142-3p的表达,发现乳腺癌细胞系内源性miR-142-3p的表达显著高于正常乳腺上皮细胞系中miR-142-3p的表达,结果提示miR-142-3p可能在乳腺癌细胞发生发展中起到调控作用。     

miR-144 reverses cisplatin resistance in cervical cancer via targeting LHX2

Mounting evidence showed that microRNAs involve in development and chemoresistance of various human cancers. We explored the roles and mechanisms of miR-144 in resistance to cisplatin (CDDP) of cervical cancer cells. miR-144 and LIM homeobox 2 (LHX2) expression in CDDP-resistant and the parental cells was determined by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot analysis, respectively. The functions of miR-144 overexpression on cell viability, the incidence of apoptosis, the activity of caspase-3/7, the cleaved-caspase-3 expression, cell migration, and invasion were determined in Hela cells and Hela/CDDP cells. Overexpression of miR-144 reduced cell viability, induced cell apoptosis, and inhibited cell migration and invasion after CDDP treatment. Besides, a luciferase reporter system demonstrated that miR-144 could directly bind to the 3′ untranslated region (3′-UTR) of LHX2 messenger RNA (mRNA). Gain expression of miR-144 decreased the expression of LHX2 both in mRNA and protein levels. Furthermore, restoration of LHX2 partly abolished the biological functions of miR-144 in resistance of cervical cancer cells. Taken together, miR-144 overcomes resistance to CDDP via promoting cell apoptosis and inhibiting invasion through targeting LHX2 in cervical cancer cells.     

miR-106b-93-25簇对子宫内膜癌细胞的调控作用研究

目的:检测mi R-106b-93-25基因簇对子宫内膜癌细胞增殖及凋亡的影响,并探讨其机制。方法:q RT-PCR检测临床子宫内膜癌标本及癌旁正常组织中mi R-106b、mi R-93和mi R-25及其宿主基因MCM7的表达情况。将micro RNA及其拮抗剂转染ECC-1细胞后,MTT实验检测ECC-1细胞增殖情况,流式细胞术检测ECC-1细胞周期及细胞凋亡情况。荧光素酶报告系统验证mi R-106b和mi R-25分别直接调控p21和Bim。结果:临床标本子宫内膜癌组织与癌旁正常组织相比mi R-106b-93-25簇及其宿主基因MCM7的表达明显增高。mi R-106b-93-25簇能够促进ECC-1细胞增殖,减少凋亡。转染mi R-106b和mi R-93的细胞出现明显的S期阻滞,过表达mi R-25的细胞凋亡明显减少。mi R-106b-93-25簇通过抑制靶基因p21和Bim的表达,引起促增殖、抗凋亡作用。结论:mi R-106b-93-25簇能够促进子宫内膜癌细胞增殖,抑制凋亡,并使细胞发生S期阻滞。mi R-106b-93-25簇在子宫内膜癌的发生与发展中具有重要的作用。     

miR-142-3p通过调控ELAVL1表达影响过氧化氢诱导的心肌细胞损伤的分子机制

目的探讨微小RNA-142-3p（miR-142-3p）对过氧化氢诱导的心肌细胞损伤的影响及其作用机制。 方法构建氧化应激损伤模型,以H9C2心肌细胞为研究对象,实验将心肌细胞转染后分为正常对照组、H₂O₂组、H₂O₂+miR-142-3p组、H₂O₂+miR阴性对照组、H₂O₂+?si-?ELAVL1组、H₂O₂+siRNA对照组、H₂O₂+miR-142-3p+pcDNA-ELAVL1组、H₂O₂+miR-?142-3p+pcDNA组。分别采用qRT-PCR与Western Blot检测细胞中miR-142-3p与ELAVL1表达;检测各组活性氧（ROS）生成水平;MTT检测细胞存活率,流式细胞术检测细胞凋亡。双荧光素酶报告实验验证miR-142-3p与ELAVL1的靶向作用。Western Blot检测细胞中Cleaved Caspase-3、STAT3、Caspase-3、p-STAT3蛋白表达。两组间比较采用两样本t检验;多组间比较采用单因素方差分析,两两比较采用LSD-t检验。 结果H₂O₂组心肌细胞中miR-142-?3p（0.26±0.06）、p-STAT3表达水平（0.36±0.04）、细胞存活率（61.73±6.48）﹪与正常对照组相比下降（P均< 0.01）,而ROS水平（1?566.38±121.57）、细胞凋亡率（27.46±1.73）﹪、Cleaved Caspase-3（0.68±0.08）及ELAVL1表达水平（4.23±0.31）均升高（P均< 0.01）;双荧光素酶报告实验证实ELAVL1是miR-142-3p的靶基因;miR-142-3p过表达或沉默ELAVL1表达可明显促进心肌细胞存活、上调p-STAT3表达,而抑制细胞凋亡及Cleaved Caspase-3表达;ELAVL1过表达可逆转miR-142-3p对过氧化氢处理H9C2细胞的保护作用。 结论miR-142-?3p可通过抑制ELAVL1表达进而减轻过氧化氢诱导的心肌细胞损伤,其可能通过影响STAT3信号通路而保护心肌细胞。     

MiR-142-3p functions as a tumor suppressor by targeting RAC1/PAK1 pathway in breast cancer

MicroRNA-142-3p (miR-142-3p) was previously investigated in various cancers, whereas, it's role in breast cancer (BC) remains far from understood. In this study, we found that miR-142-3p was markedly decreased both in cell lines and BC tumor tissues. Elevated miR-142-3p expression suppressed growth and metastasis of BC cell lines via gain-of-function assay in vitro and in vivo. Mechanistically, miR-142-3p could regulate the ras-related C3 botulinum toxin substrate 1 (RAC1) expression in protein level, which simultaneously suppressed the epithelial-to-mesenchymal transition related protein levels and the activity of PAK1 phosphorylation, respectively. In addition, rescue experiments revealed RAC1 overexpression could reverse tumor-suppressive role of miR-142-3p. Our results showed miR-142-3p could function as a tumor suppressor via targeting RAC1/PAK1 pathway in BC, suggesting a potent therapeutic target for BC treatment.     

Overexpression of miR-493-3p suppresses ovarian cancer cell proliferation,migration and invasion through downregulating DPY30

Accumulating evidence has verified that the aberrant expression level of miR-493?3p is often associated with the occurrence of numerous cancers. Nevertheless, the expression level and effect of this microRNA in ovarian cancer (OC) remain largely unclear. Therefore, the molecular function of miR-493?3p in OC progression was systematically investigated in this study.The expression of miR-493?3p and DPY30 was assessed by qRT-PCR. The protein expression level of DPY30 in cell lines was further assessed by western blot. Cell viability was respectively examined in vitro functional experiments including CCK-8 assay, EdU assay, wound healing assay, colony formation and apoptosis assays as well as the scratch test and transwell assay. Bioinformatics analysis and luciferase reporter assays were performed to predict and clarity of the correlation between miR-493?3p and DPY30.The expression of miR-493?3p was significantly reduced in OC tissues and cells. Functional experimental results showed that miR-493?3p suppressed cellular proliferation, migration, invasion, but promoted apoptosis in OC cells. Mechanistically, we also confirmed that DPY30 could be directly targeted by miR-493?3p based on bioinformatics and dual-luciferase reporter analysis. Rescue experiments results indicated that the inhibitory effect of miR-493?3p on cellular proliferation, migration and invasion and the promotive effect of miR-493?3p on apoptosis was abolished by DPY30 overexpression.Our findings demonstrated the antitumor effect of miR-493?3p through targeting DPY30 in ovarian cancer, indicating that miR-493?3p might represent a promising target for ovarian cancer diagnosis and treatment.     

Homoharringtonine inhibited breast cancer cells growth via miR-18a-3p/AKT/mTOR signaling pathway

Homoharringtonine (HHT), a natural alkaloid derived from the cephalotaxus, exhibited its anti-cancer effects in hematological malignancies clinically. However, its pesticide effects and mechanisms in treating solid tumors remain unclear. In this study, we found that HHT was capable of inhibiting tumor growth after 5-days treatment of breast cancer cells, MCF-7, in vivo. Furthemore, HHT also significantly inhibited the cancer cell growth and induced cell apoptosis in vitro. miRNA sequencing proved miR-18a-3p was noticeably downregulated in the cells after HHT treatment. Moreover, downregulating miR-18a-3p increased HHT-induced cell apoptosis; our data supported that HHT suppressed miR-18a-3p expression and inhibited tumorigenesis might via AKT-mTOR signaling pathway. In conclusion: our study proved that HHT suppressed breast cancer cell growth and promoted apoptosis mediated by regulating of the miR-18a-3p-AKT-mTOR signaling pathway, HHT may be a promising antitumor agent in breast cancer treatment.     

microRNA-383 regulates cell viability and apoptosis by mediating Wnt/β-catenin signaling pathway in non–small cell lung cancer

The aim of this study was to investigate the roles of microRNA-383 (miRNA-383) in progression of non–small cell lung cancer (NSCLC) and the potential mechanism. The expressions of miR-383 and Wnt1 protein were detected in lung cancer tissues and cells by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot analysis. After the transfection of miR-383 mimics, si-Wnt1 or miR-383+Wnt1, the viability and apoptosis of NSCLC cells were detected by cell counting kit-8 and terminal deoxynucleotidyl transferase–mediated dUTP nick-end labeling, respectively. The interaction between miR-383 and Wnt1 was investigated by luciferase activity and Western blot analysis. Cells stably transfected with miR-383 mimics were inoculated into the right axillary of nude mice by subcutaneous injection. The tumor volume and weight were measured, and the expressions of miR-383, Wnt1, β-catenin, and cyclin D1 were detected by qRT-PCR and Western blot analysis. The expression of miR-383 was significantly decreased, and the level of Wnt1 was significantly increased (P < 0.05) in lung cancer tissues and cells. Upregulation of miR-383 or inhibition of Wnt1 expression inhibited the cell viability and induce apoptosis in NSCLC cells. Moreover, Wnt1 was the target gene of miR-383, and its overexpression weakened the regulatory effect of miR-383 on cell viability and apoptosis in NSCLC cells. Besides, the addition of miR-383 decreased the tumor volume and size and inhibited the expressions of Wnt1, β-catenin, and cyclin D1 at the protein level in nude mice. Collectively, miR-383 induced apoptosis and inhibited cell viability as well as tumorigenic capacity in nude mice via regulating the Wnt/β-catenin signaling pathway.     

Downregulation of miR-33b promotes non-small cell lung cancer cell growth through reprogramming glucose metabolism miR-33b regulates non-small cell lung cancer cell growth

Glucose metabolism is a common target for cancer regulation and microRNAs (miRNAs) are important regulators of this process. Here we aim to investigate a tumor-suppressing miRNA, miR-33b, in regulating the glucose metabolism of non-small cell lung cancer (NSCLC). In our study, quantitative real-time polymerase chain reaction (qRT-PCR) showed that miR-33b was downregulated in NSCLC tissues and cell lines, which was correlated with increased cell proliferation and colony formation. Overexpression of miR-33b through miR-33b mimics transfection suppressed NSCLC proliferation, colony formation, and induced cell-cycle arrest and apoptosis. Meanwhile, miR-33b overexpression inhibited glucose metabolism in NSCLC cells. Luciferase reporter assay confirmed that miR-33b directly binds to the 3′-untranslated region of lactate dehydrogenase A (LDHA). qRT-PCR and Western blot analysis showed that miR-33b downregulated the expression of LDHA. Moreover, introducing LDHA mRNA into cells over-expressing miR-33b attenuated the inhibitory effect of miR-33b on the growth and glucose metabolism in NSCLC cells. Taken together, these results confirm that miR-33b is an anti-oncogenic miRNA, which inhibits NSCLC cell growth by targeting LDHA through reprogramming glucose metabolism.     

A cyclin D1/microRNA 17/20 regulatory feedback loop in control of breast cancer cell proliferation

Decreased expression of specific microRNAs (miRNAs) occurs in human tumors, which suggests a function for miRNAs in tumor suppression. Herein, levels of the miR-17-5p/miR-20a miRNA cluster were inversely correlated to cyclin D1 abundance in human breast tumors and cell lines. MiR-17/20 suppressed breast cancer cell proliferation and tumor colony formation by negatively regulating cyclin D1 translation via a conserved 3' untranslated region miRNA-binding site, thereby inhibiting serum-induced S phase entry. The cell cycle effect of miR-17/20 was abrogated by cyclin D1 siRNA and in cyclin D1-deficient breast cancer cells. Mammary epithelial cell-targeted cyclin D1 expression induced miR-17-5p and miR-20a expression in vivo, and cyclin D1 bound the miR-17/20 cluster promoter regulatory region. In summary, these studies identify a novel cyclin D1/miR-17/20 regulatory feedback loop through which cyclin D1 induces miR-17-5p/miR-20a. In turn, miR-17/20 limits the proliferative function of cyclin D1, thus linking expression of a specific miRNA cluster to the regulation of oncogenesis.