MiR-195 inhibits the growth and metastasis of NSCLC cells by targeting IGF1R

Insulin receptor alternative splicing in breast and prostate cancer

Cancer etiology represents an intricate, multifactorial orchestration where metabolically associated insulin-like growth factors (IGFs) and insulin foster cellular proliferation and growth throughout tumorigenesis. The insulin receptor (IR) exhibits two splice variants arising from alternative mRNA processing, namely IR-A, and IR-B, with remarkable distribution and biological effects disparities. This insightful review elucidates the structural intricacies, widespread distribution, and functional significance of IR-A and IR-B. Additionally, it explores the regulatory mechanisms governing alternative splicing processes, intricate signal transduction pathways, and the intricate association linking IR-A and IR-B splicing variants to breast and prostate cancer tumorigenesis. Breast cancer and prostate cancer are the most common malignant tumors with the highest incidence rates among women and men, respectively. These findings provide a promising theoretical framework for advancing preventive strategies, diagnostic modalities, and therapeutic interventions targeting breast and prostate cancer.

Long intergenic non-protein-coding RNA 1547 acts as a competing endogenous RNA and exerts cancer-promoting activity in non-small cell lung cancer by targeting the microRNA-195-5p/ homeobox C8 axis

Long intergenic non-protein coding RNA 1547 (LINC01547) presents a notable relationship with prognosis in patients with ovarian cancer. Herein, we examined the expression of LINC01547 in non-small cell lung cancer (NSCLC) to ascertain its clinical significance. We also explored the detailed functions of LINC01547 in regulating the aggressive phenotype of NSCLC and the molecular mechanism of action underlying its carcinogenic activities events in NSCLC. Furthermore, we applied the data acquired from the tissue specimens and the Cancer Genome Atlas (TCGA) database to analyze the level of LINC01547 in NSCLC and conducted functional assays to address the regulatory effect of LINC01547. Further, we examined the mechanistic interaction among LINC01547, microRNA-195-5p (miR-195-5p), and homeobox C8 (HOXC8) using bioinformatics prediction and luciferase reporter assay. LINC01547 was noticeably overexpressed, as affirmed by data from TCGA and our own cohort; moreover, poor prognosis was associated with increased LINC01547 levels in patients with NSCLC. LINC01547 regulates cell proliferation, colony-forming, migration, and invasion, and its absence produced tumor-repressing effects in NSCLC. Mechanistically, as a competitive endogenous RNA, LINC01547 decoyed miR-195-5p and consequently resulted in the overexpression of HOXC8 in NSCLC cells. Using rescue experiments, we found that the regulatory activities of LINC01547 deficient in repressing the malignant properties of NSCLC cells could be counteracted by hindering miR-195-5p or overexpressing HOXC8. Conclusively, LINC01547 serves as a crucial component to worsen the oncogenicity of NSCLC cells by controlling the miR-195-5p/HOXC8 axis. Thus, the newly identified competing endogenous RNA pathway may potentially be an attractive therapeutic for NSCLC management.

MiRNA expression profiling in adenocarcinoma and squamous cell lung carcinoma reveals both common and specific deregulated microRNAs

The current study investigated the expression signatures of miRNAs in lung adenocarcinoma (LUAD) and squamous cell lung carcinoma (LUSC). miRNA profiling was performed using microarray in 12 LUAD and 12 LUSC samples and adjacent normal tissues. In LUAD, 107 miRNAs were significantly deregulated, whereas 235 miRNAs were deregulated in LUSC. Twenty-six miRNAs were common between the 2 cancer subtypes and 8 were prioritized for validation, in addition to 6 subtype-specific miRNAs. The RT-qPCR validation samples included 50 LUAD, 50 LUSC, and adjacent normal tissues. Eight miRNAs were validated in LUAD: 3 upregulated - miR-7-5p, miR-375-5p, miR-6785-3p, and 5 downregulated - miR-101-3p, miR-139-5p, miR-140-3p, miR-144-3p, miR-195-5p. Ten miRNAs were validated in the LUSC group: 3 upregulated - miR-7-5p, miR-21-3p, miR-650, and 7 downregulated - miR-95-5p, miR-140-3p, miR-144-3p, miR-195-5p, miR-375, miR-744-3p, and miR-4689-3p. Reactome pathway analysis revealed that the target genes of the deregulated miRNAs in LUAD were significantly enriched in cell cycle, membrane trafficking, gene expression processes, and EGFR signaling, while in LUSC, they were enriched in the immune system, transcriptional regulation by TP53, and FGFR signaling. This study identified distinct miRNA profiles in LUSC and LUAD, which are common and specific miRNAs that could be further investigated as biomarkers for diagnosis and prognosis.

Spectrum of microRNAs and their target genes in cancer: intervention in diagnosis and therapy

Till date, several groups have studied the mechanism of microRNA (miRNA) biogenesis, processing, stability, silencing, and their dysregulation in cancer. The miRNA coding genes recurrently go through abnormal amplification, deletion, transcription, and epigenetic regulation in cancer. Some miRNAs function as tumor promoters while few others are tumor suppressors based on the transcriptional regulation of target genes. A review of miRNAs and their target genes in a wide range of cancers is attempted in this article, which may help in the development of new diagnostic tools and intervention therapies. The contribution of miRNAs for drug sensitivity or resistance in cancer therapy and opportunities of miRNAs in cancer prognosis or diagnosis and therapy is also presented in detail.

Circulating microRNA profile in humans and mice with congenital GH deficiency

Reduced inflammation, increased insulin sensitivity, and protection against cancer are shared between humans and mice with GH/IGF1 deficiency. Beyond hormone levels, miRNAs are important regulators of metabolic changes associated with healthy aging. We hypothesized that GH deficiency in humans alters the abundance of circulating miRNAs and that a subset of those miRNAs may overlap with those found in GH-deficient mice. In this study, subjects with untreated congenital isolated GH deficiency (IGHD; n = 23) and control subjects matched by age and sex (n = 23) were recruited and serum was collected for miRNA sequencing. Serum miRNAs from young (6 month) and old (22 month) Ames dwarf (df/df) mice with GH deficiency and their WT littermates (n = 5/age/genotype group) were used for comparison. We observed 14 miRNAs regulated with a genotype by age effect and 19 miRNAs regulated with a genotype effect independent of age in serum of IGHD subjects. These regulated miRNAs are known for targeting pathways associated with longevity such as mTOR, insulin signaling, and FoxO. The aging function was overrepresented in IGHD individuals, mediated by hsa-miR-31, hsa-miR-146b, hsa-miR-30e, hsa-miR-100, hsa-miR-181b-2, hsa-miR-195, and hsa-miR-181b-1, which target the FoxO and mTOR pathways. Intriguingly, miR-181b-5p, miR-361-3p, miR-144-3p, and miR-155-5p were commonly regulated in the serum of humans and GH-deficient mice. In vitro assays confirmed target genes for the main up-regulated miRNAs, suggesting miRNAs regulated in IGHD individuals can regulate the expression of age-related genes. These findings indicate that systemic miRNAs regulated in IGHD individuals target pathways involved in aging in both humans and mice.

Long non-coding RNA SLC25A25-AS1 exhibits oncogenic roles in non-small cell lung cancer by regulating the microRNA-195-5p/ITGA2 axis

Long non-coding RNA SLC25A25 antisense RNA 1 (SLC25A25-AS1) exerts antitumour activity in colorectal cancer. The present study investigated whether SLC25A25-AS1 is implicated in the aggressiveness of non-small cell lung cancer (NSCLC) and the possible underlying mechanism. SLC25A25-AS1 expression in NSCLC was determined by reverse transcription-quantitative PCR. The proliferation, apoptosis, migration and invasion of NSCLC cells were tested in vitro through cell counting kit-8 assay, flow cytometry analysis, Transwell migration and invasion assays, followed by in vivo validation using animal experiments. Additionally, the competitive endogenous RNA theory for SLC25A25-AS1, microRNA-195-5p (miR-195-5p) and integrin α2 (ITGA2) was identified using subcellular fractionation, bioinformatics analysis, reverse transcription-quantitative PCR, western blotting, a luciferase assay and RNA immunoprecipitation. As compared with normal lung tissues, increased expression of SLC25A25-AS1 was demonstrated in NSCLC tissues using The Cancer Genome Atlas database.. In addition, SLC25A25-AS1 was overexpressed in both NSCLC tissues and cell lines. High SLC25A25-AS1 expression was markedly associated with shorter overall survival time of patients with NSCLC. SLC25A25-AS1 silencing impeded NSCLC cell proliferation and triggered apoptosis, while restricting cell migration and invasion. Tumour growth in vivo was also impaired by SLC25A25-AS1 silencing. Mechanistically, SLC25A25-AS1 was demonstrated to be an miR-195-5p sponge in NSCLC cells. miR-195-5p mimics decreased ITGA2 expression in NSCLC cells by directly targeting ITGA2, and SLC25A25-AS1 interference decreased ITGA2 expression by sequestering miR-195-5p. Furthermore, the antitumour effects of SLC25A25-AS1 silencing on malignant behaviours were counteracted when ITGA2 was restored or when miR-195-5p was silenced. In summary, by controlling the miR-195-5p/ITGA2 axis, SLC25A25-AS1 served tumour-promoting roles in NSCLC cells. Therefore, the SLC25A25-AS1/miR-195-5p/ITGA2 signalling pathway might be an attractive target for future therapeutic options in NSCLC.

miR-195-5p exerts tumor-suppressive functions in human lung cancer cells through targeting TrxR2

miR-195-5p has been widely explored in various cancers and is considered as a tumor-suppressive microRNA. However, its roles in human lung cancer pathogenesis are not fully elucidated. In this study, we aimed to explore how miR-195-5p is involved in malignant behaviors of lung adenocarcinoma (LUAD) cells. miR-195-5p expression was examined in the tumor tissues of patients with LUAD and human LUAD cell lines including A549 and PC-9. Thioredoxin reductase 2 (TrxR2) was predicted to be an mRNA target of miR-195-5p using online tools and validated by the Dual-Luciferase Reporter Assay. Lentivirus infection was used for gene overexpression, while gene knockdown was achieved by RNA interference. Cell proliferation was determined by Cell Counting Kit-8 and 5-ethynyl-2'-deoxyuridine methods, and cell migration and invasion were assayed with transwell experiments. Cell apoptosis was determined by annexin V staining-based flow cytometry. The antitumor effects of miR-195-5p were also evaluated in nude mice xenografted with A549 cells. We found that miR-195-5p was lowly expressed in human LUAD cells, and its overexpression markedly suppressed cell proliferation, migration, and invasion and increased the apoptosis of LUAD cells in vitro. TrxR2 knockdown phenocopied the tumor-suppressive effects of miR-195-5p overexpression, while simultaneous TrxR2 overexpression remarkably reversed the effects of miR-195-5p overexpression on malignant behaviors of A549 and PC-9 cells. Additionally, miR-195-5p overexpression inhibited the growth of xenografted A549 tumor in nude mice. Our work verified that miR-195-5p exerts tumor-suppressive functions in LUAD cells through targeting TrxR2 and suggested that the miR-195-5p/TrxR2 axis is a potential biomarker for LUAD therapy.

MicroRNA-195 controls MICU1 expression and tumor growth in ovarian cancer

MICU1 is a mitochondrial inner membrane protein that inhibits mitochondrial calcium entry; elevated MICU1 expression is characteristic of many cancers, including ovarian cancer. MICU1 induces both glycolysis and chemoresistance and is associated with poor clinical outcomes. However, there are currently no available interventions to normalize aberrant MICU1 expression. Here, we demonstrate that microRNA-195-5p (miR-195) directly targets the 3' UTR of the MICU1 mRNA and represses MICU1 expression. Additionally, miR-195 is under-expressed in ovarian cancer cell lines, and restoring miR-195 expression reestablishes native MICU1 levels and the associated phenotypes. Stable expression of miR-195 in a human xenograft model of ovarian cancer significantly reduces tumor growth, increases tumor doubling times, and enhances overall survival. In conclusion, miR-195 controls MICU1 levels in ovarian cancer and could be exploited to normalize aberrant MICU1 expression, thus reversing both glycolysis and chemoresistance and consequently improving patient outcomes.

Integrative analyses of noncoding RNAs reveal the potential mechanisms augmenting tumor malignancy in lung adenocarcinoma

Precise noncoding RNA (ncRNA)-based network prediction is necessary to reveal ncRNA functions and pathological mechanisms. Here, we established a systemic pipeline to identify prognostic ncRNAs, predict their functions and explore their pathological mechanisms in lung adenocarcinoma (LUAD). After in silico and experimental validation based on evaluations of prognostic value in multiple LUAD cohorts, we selected the PTTG3P pseudogene from among other prognostic ncRNAs (MIR497HG, HSP078, TBX5-AS1, LOC100506990 and C14orf64) for mechanistic studies. PTTG3P upregulation in LUAD cells shortens the metaphase to anaphase transition in mitosis, increases cell viability after cisplatin or paclitaxel treatment, facilitates tumor growth that leads to poor survival in orthotopic lung models, and is associated with a poor survival rate in LUAD patients in the TCGA cohort who received chemotherapy. Mechanistically, PTTG3P acts as an ncRNA that interacts with the transcription factor FOXM1 to regulate the transcriptional activation of the mitotic checkpoint kinase BUB1B, which augments tumor growth and chemoresistance and leads to poor outcomes for LUAD patients. Overall, we established a systematic strategy to uncover prognostic ncRNAs with functional prediction methods suitable for pan-cancer studies. Moreover, we revealed that PTTG3P, due to its upregulation of the PTTG3P/FOXM1/BUB1B axis, could be a therapeutic target for LUAD patients.

MiR-195 and miR-497 suppress tumorigenesis in lung cancer by inhibiting SMURF2-induced TGF-β receptor I ubiquitination

SMURF2 is a member of the HECT family of E3 ubiquitin ligases that have important roles as a negative regulator of transforming growth factor‐β (TGF‐β) signaling through ubiquitin‐mediated degradation of TGF‐β receptor I. However, the regulatory mechanism of SMURF2 is largely unknown. In this study, we identified that micro(mi)R‐195 and miR‐497 putatively target SMURF2 using several target prediction databases. Both miR‐195 and miR‐497 bind to the 3′‐UTR of the SMURF2 mRNA and inhibit SMURF2 expression. Furthermore, miR‐195 and miR‐497 regulate SMURF2‐dependent TβRI ubiquitination and cause the activation of the TGF‐β signaling pathway in lung cancer cells. Upregulation of miR‐195 and miR‐497 significantly reduced cell viability and colony formation through the activation of TGF‐β signaling. Interestingly, miR‐195 and miR‐497 also reduced the invasion ability of lung cancer cells when cells were treated with TGF‐β1. Subsequent in vivo studies in xenograft nude mice model revealed that miR‐195 and miR‐497 repress tumor growth. These findings demonstrate that miR‐195 and miR‐497 act as a tumor suppressor by suppressing ubiquitination‐mediated degradation of TGF‐β receptors through SMURF2, and suggest that miR‐195 and miR‐497 are potential therapeutic targets for lung cancer.

A novel long non-coding RNA LINC00355 promotes proliferation of lung adenocarcinoma cells by down-regulating miR-195 and up-regulating the expression of CCNE1

Lung adenocarcinoma is the most common subtype of non-small-cell lung cancer affecting people all over the globe. Recent studies have indicated that long non-coding RNAs (lncRNAs) possess the ability to regulate gene expression. Initially, we uncovered increased LINC00355 expressions in lung adenocarcinoma tissues and cells. Functionally, our findings demonstrated that LINC00355 silencing suppressed the proliferation in vitro and in vivo. In addition, we found that LINC00355 negatively regulated miR-195 in lung adenocarcinoma cells. Simultaneously, silencing LINC00355 by shRNA resulted in suppressed proliferation, colony formation and promoted cell cycle arrest and apoptosis via miR-195. Moreover, silencing LINC00355 by shRNA inhibited the cyclin E1 (CCNE1) gene expression via miR-195 in lung adenocarcinoma cells. Collectively, this study demonstrates the novel lncRNA LINC00355 in regulatory network of CCNE1 via miR-195 in lung adenocarcinoma, highlighting LINC00355 as a new target for the treatment of lung adenocarcinoma.

MicroRNA‑195 suppresses rectal cancer growth and metastasis via regulation of the PI3K/AKT signaling pathway

MicroRNAs (miRNAs) play a vital role in the progression of cancer, however, only limited data on miRNAs in rectal cancer are available. The aim of the present study was to investigate whether miR-195 could inhibit the progression of rectal cancer. The miR-195 mimic was transfected into 2 types of human rectal cancer cells (SW837 and SW1463). Cell viability and apoptosis were analyzed by Cell Counting Kit-8 (CCK-8) assay and flow cytometry, and cell migration and invasion were assessed by scratch test and Transwell assay. The results revealed that insulin-like growth factor 1 (IGF1) was predicted as a potential target of miR-195 by Targetscan7.2, and the result was verified by dual-luciferase reporter assay. The co-transfection of IGF1 was performed to confirm the underlying mechanism of tumor suppressor of miR-195 in rectal cancer. The activation of PI3K/AKT signaling was determined by western blotting. The levels of miR-195 in SW837 and SW1463 cells were revealed to be lower than in human rectal mucosa epithelial cells. After the transfection with miR-195, the cell viability was decreased, while the apoptosis was significantly increased (SW837: 5.21% vs. 20.96%; SW1463: 4.19% vs. 25.22%). Moreover, cell migration and invasion were significantly inhibited in the mimic group. miR-195 specifically targeted IGF1, however, the co-transfection of IGF1 could partially reverse the inhibitory effects of miR-195 on rectal cancer cells. It was also determined that the phosphorylation of PI3K and AKT were significantly inhibited in the mimic group. The tumor suppressive ability of miR-195 in rectal cancer cell proliferation and metastasis was mediated by blocking IGF1 expression and inhibiting the PI3K/AKT pathway.

MiR-143-3p suppresses the progression of nasal squamous cell carcinoma by targeting Bcl-2 and IGF1R

Dysregulated microRNAs (miRNAs) play crucial roles in the occurrence and development of multiple tumours, but their roles in the progression of nasal squamous cell carcinoma (NSCC) remain unknown. The aim of our study was to investigate the potential function and molecular mechanism of miR-143-3p in NSCC. Expression of miRNA and mRNA was detected by quantitative real-time reverse transcription-PCR (qRT-PCR). Forced overexpression of miR-143-3p was established by transfecting mimics into NSCC cell line. Then, we investigated the role of miR-143-3p in human NSCC cell proliferation, apoptosis, cycle and migration by using MTT, flow cytometry and transwell assays. Bioinformatics analysis, qRT-PCR, Western blot and luciferase reporter analysis were performed to validate the relationship between miR-143-3p and its potential targets. We found that miR-143-3p was substantially downregulated in human NSCC tissues and cell line. Forced upregulation of miR-143-3p significantly attenuated cell proliferation and migration. Furthermore, this change could induce apoptosis and G1-phase arrest of NSCC cells. Mechanistically, miR-143-3p directly targeted and significantly suppressed Bcl-2 and IGF1R expression. In summary, miR-143-3p regulation of the proliferation, apoptosis, cell cycle and migration of NSCC probably partly depends on inhibition of Bcl-2 and IGF1R, indicating that miR-143-3p may be a novel molecular therapeutic target for NSCC.

miR‑195 suppresses metastasis and angiogenesis of squamous cell lung cancer by inhibiting the expression of VEGF

MicroRNAs (miRNAs) are small, noncoding RNAs that are ~22 nucleotides in length. Accumulating evidence has revealed that miRNAs act as oncogenes or tumor suppressors in various human cancers. In order to investigate the role of miR-195- in squamous cell lung cancer (SQCLC) cells, and to determine the underlying mechanism, the present study utilized RT-qPCR, western blot analysis, luciferase assay, MTT assay, cell migration assay, and in vitro angiogenesis techniques. The results obtained revealed that miR-195-5p acted as a tumor suppressor in SQCLC cells. The expression levels of miR-195 were decreased in two SQCLC cell lines (H520 and SK-Mes-1) compared with a normal lung cell line, and miR-195 directly targeted the 3′-untranslated region of vascular endothelial growth factor (VEGF) in SQCLC cells. Additionally, miR-195 upregulation suppressed the viability and migration of SQCLC cells. Furthermore, miR-195 inhibited the growth and tube formation of endothelial vascular cells. Collectively, the findings indicated that miR-195 downregulated VEGF, and that targeting this miRNA may provide an effective approach to inhibit angiogenesis in tumors.

MS-275 potentiates the effect of YM-155 in lung adenocarcinoma via survivin downregulation induced by miR-138 and miR-195

Background

YM‐155 has been proven to be an efficient antitumor suppressor in non‐small cell lung cancer (NSCLC) cells. However, the suppressive effect of YM‐155 on the expression of survivin is not sufficient and has a short half‐life. MS‐275, a histone deacetylase inhibitor, has significant antitumor capacity with a relatively long half‐life. Our study explored whether MS‐275 could enhance the inhibitory effect of YM‐155 on LUAD proliferation.

Methods

To investigate the synergistic effect of MS‐275 and YM‐155, we employed methyl thiazolyl tetrazolium and colony formation assays to access the inhibition effect of MS‐275, YM‐155, or a combination in A549 and HCC827 cell lines. We then detected the effect of MS‐275 and YM‐155 on the expression of survivin and pro‐apoptotic proteins by Western blot and miR‐138 or miR‐195 expression by quantitative PCR. We also analyzed the methylation level of microRNAs (miRNAs) using methylation‐sensitive quantitative PCR. Finally, we investigated the interaction between miRNAs and survivin by luciferase reporter assay.

Results

MS‐275 facilitated an inhibitory effect of YM‐155 on lung adenocarcinoma cell proliferation. MS‐275 can upregulate the level of acetylated H3, promote the degradation of DNA methyltransferases, and inhibit the methylation of miR‐138 and miR‐195 genes to elevate the expression of miR‐138 and miR‐195. Moreover, miR‐138 and miR‐195 showed a synergistic effect with YM‐155 by directly binding to the 3 untranslated region of survivin to attenuate its expression.

Conclusion

For the first time, we report the synergistic effective of MS‐275 and YM‐155 and suggest a new direction for the future application of YM‐155.

MicroRNA-195 suppresses the progression of lung adenocarcinoma by directly targeting apelin

Background

Apelin plays an important role in many types of tumors. We aimed to identify the effects of miR‐195 on inhibiting apelin and clarify the regulating mechanism of miR‐195‐apelin in lung adenocarcinoma cells.

Methods

We detected the expression levels of apelin and miR‐195 in lung adenocarcinoma tissues and lung cancer cell lines using Western blotting and quantitative reverse transcription PCR assay, respectively. Luciferase reporter assay was used to confirm the target gene of miR‐195. The effects of miR‐195 and apelin on the proliferation and cell cycle of lung adenocarcinoma cells were assessed by methyl thiazolyl tetrazolium and colony formation assays, and flow cytometry. Wound‐healing and transwell invasion experiments were employed to examine cellular migration and invasion. A tumor xenograft model was then used to investigate the role of miR‐195 on tumor growth in vivo.

Results

The expression level of apelin and miR‐195 showed an inverse correlation in lung adenocarcinoma tissues and cell lines. Luciferase reporter assay suggested that miR‐195 directly targets apelin messenger RNA. Overexpression of miR‐195 significantly inhibited the proliferation, migration, and invasion of lung adenocarcinoma cells in vitro and suppressed tumor growth in vivo. Further analysis revealed that apelin is one of the functional target genes of miR‐195, and the overexpression of apelin efficiently inhibits the promotion of cell proliferation and invasion mediated by miR‐195 mimics in lung adenocarcinoma cells.

Conclusions

Our data constitute evidence that miR‐195 inhibits lung adenocarcinoma cell proliferation and invasion though targeting apelin and provides novel insight into the mechanism underlying the development of lung adenocarcinoma.

The role of miRNA regulation in fetal cardiomyocytes, cardiac maturation and the risk of heart disease in adults

Myocardial infarction is a primary contributor towards the global burden of cardiovascular disease. Rather than repairing the existing damage of myocardial infarction, current treatments only address the symptoms of the disease and reducing the risk of a secondary infarction. Cardiac regenerative capacity is dependent on cardiomyocyte proliferation, which concludes soon after birth in humans and precocial species such as sheep. Human fetal cardiac tissue has some ability to repair following tissue damage, whereas a fully matured human heart has minimal capacity for cellular regeneration. This is in contrast to neonatal mice and adult zebrafish hearts, which retain the ability to undergo cardiomyocyte proliferation and can regenerate cardiac tissue after birth. In mice and zebrafish models, microRNAs (miRNAs) have been implicated in the regulation of genes involved in cardiac cell cycle progression and regeneration. However, the significance of miRNA regulation in cardiomyocyte proliferation for humans and other large mammals, where the timing of heart development in relation to birth is similar, remains unclear. miRNAs may be valuable targets for therapies that promote cardiac repair after injury. Therefore, elucidating the role of specific miRNAs in large animals, where heart development closely resembles that of humans, remains vitally important for identifying therapeutic targets that may be translated into clinical practice focused on tissue repair.

MicroRNA-195: a review of its role in cancers

MicroRNAs (miRNAs) are small and highly conserved noncoding RNAs that regulate gene expression at the posttranscriptional level by binding to the 3′-UTR of target mRNAs. Recently, increasing evidence has highlighted their profound roles in various pathological processes, including human cancers. Deregulated miRNAs function as either oncogenes or tumor suppressor genes in multiple cancer types. Among them, miR-195 has been reported to significantly impact oncogenicity in various neoplasms by binding to critical genes and signaling pathways, enhancing or inhibiting the progression of cancers. In this review, we focus on the expression of miR-195 in regulatory mechanisms and tumor biological processes and discuss the future potential therapeutic implications of diverse types of human malignancies.

The novel hsa-miR-12528 regulates tumourigenesis and metastasis through hypo-phosphorylation of AKT cascade by targeting IGF-1R in human lung cancer

Lung cancer cases are increasing yearly; however, few novel therapeutic strategies for treating this disease have been developed. Here the dysregulation between microRNAs and oncogenes or tumour-suppressor genes forms a close connection-loop to the development or progression in human lung carcinogenesis. That is, the relationship between microRNAs and carcinogenic mechanism may find the critical clue to improve the treatment efficacy. Accordingly, we identified and characterised a novel microRNA, hsa-miR-12528, in A549 cells. The miR-12528 expression was aberrantly downregulated in cancer cell lines and in the patient tissues derived from human non-small cell lung cancer. In addition, we found that miR-12528 post-transcriptionally controls the translation of the insulin-like growth factor 1 receptor (IGF-1R) gene by directly targeting the 3′-untranslated region of IGF-1R mRNA. Notably, the IGF-1R gene is elevated in the majority of cancers and may be an attractive therapeutic target for anticancer therapy because elevated IGF-1R mediates the signalling amplification of a major oncogenic pathway in neoplasia. In A549 cells, miR-12528 overexpression epigenetically altered the downstream phosphorylation of the primary IGF-1R networks, negatively regulated proliferation, apoptosis and migratory activity, and consequently inhibited tumourigenesis and metastasis in vivo. Therefore, our discovery of hsa-miR-12528 may be able to be applied to the development of molecular-target therapeutic strategies and diagnosis-specific biomarkers for human lung cancer.

Circulating microRNAs as potential cancer biomarkers: the advantage and disadvantage

MicroRNAs are endogenous single-stranded non-coding small RNA molecules that can be secreted into the circulation and exist stably. They usually exhibit aberrant expression under different physiological and pathological conditions. Recently, differentially expressed circulating microRNAs were focused on as potential biomarkers for cancer screening. We herein review the role of circulating microRNAs for cancer diagnosis, tumor subtype classification, chemo- or radio-resistance monitoring, and outcome prognosis. Moreover, circulating microRNAs still have several issues hindering their reliability for the practical clinical application. Future studies need to elucidate further potential application of circulating microRNAs as specific and sensitive markers for clinical diagnosis or prognosis in cancers.

miR-195 potentiates the efficacy of microtubule-targeting agents in non-small cell lung cancer

Microtubule-targeting agents (MTAs) are widely used for the treatment of non-small cell lung cancer (NSCLC). The response rate is only ∼25%, mainly attributable to drug resistance. To identify determinants of resistance in NSCLC, we performed a high-throughput screen using a library of miRNA mimics. Here we report that miR-195 synergizes with MTAs to inhibit the growth of NSCLC cells in vitro, that increased expression of miR-195 sensitizes NSCLC cells to MTAs and that repression of miR-195 confers resistance to MTAs. We show that NSCLC tumors over-expressing miR-195 are more sensitive to MTA treatment and that induced expression of miR-195 in NSCLC tumors potentiates the anti-tumor effect of MTAs. Additionally, we demonstrate that miR-195 targets checkpoint kinase 1 (CHEK1) to regulate the response of NSCLC cells to MTAs, that over-expression of CHEK1 contributes to resistance to MTAs and that knock-down of CHEK1 synergizes with MTAs to repress cell growth. Our results highlight the importance of miR-195 in regulating the response of NSCLC cells to MTAs and underline the potential application of miR-195 as a biomarker for response to MTAs, and as a therapeutic adjuvant to MTA treatment.

miR-195 targets cyclin D3 and survivin to modulate the tumorigenesis of non-small cell lung cancer

miR-195 has recently been reported to function as a tumor suppressor in various cancers, including non-small cell lung cancer (NSCLC). However, the mechanisms by which miR-195 represses the tumorigenesis of NSCLC cells are not fully understood. We performed a high-throughput screen using an miRNA mimic library and confirmed the identification of miR-195 as a tumor suppressor in NSCLC. We demonstrated that overexpression or induced expression of miR-195 in lung tumors slows tumor growth and that repression of miR-195 accelerates tumor growth. In addition, we found that knockout of miR-195 promotes cancer cell growth. We demonstrated that miR-195 targets cyclin D3 to cause cell cycle arrest at the G1 phase and that miR-195 targets survivin to induce apoptosis and senescence in NSCLC cells. Overexpression of cyclin D3 or survivin reverses the effects of miR-195 in NSCLC cells. Through the analysis of data from The Cancer Genome Atlas, we confirmed that the expression of miR-195 is lower in tumors than in adjacent normal tissues and that low expression of miR-195 is associated with poor survival in both lung adenocarcinoma and squamous cell carcinoma patients. Specifically, we found that BIRC5, which codes for survivin, is upregulated in both adenocarcinoma and squamous cell carcinoma tissues and that high expression of BIRC5 is associated with poor survival in adenocarcinoma, but not squamous cell carcinoma. In addition, the ratio of miR-195 level to BIRC5 level is associated with both recurrence-free and overall survival in lung adenocarcinoma. Our results suggest that the miR-195/BIRC5 axis is a potential target for treatment of lung adenocarcinoma specifically, and NSCLC in general.

Epigenome-Based Precision Medicine in Lung Cancer

Lung cancer is the leading cause of cancer-related deaths in the world. Despite significant advances in the early detection and treatment of the disease, the prognosis remains poor, with an overall 5-year survival rate ranging from 15% to 20%. This poor prognosis results largely from early micrometastatic spread of cancer cells to nearby lymph nodes or tissues and partially from early recurrence after curative surgical resection. Recently, precision medicines that target potential oncogenic driver mutations have been approved to treat lung cancer. However, some lung cancer patients do not have targetable mutations, and many patients develop resistance to targeted therapy. Tumor heterogeneity and mutational density are also challenges in treating lung cancer, which underscores the need for developing alternative therapeutic strategies for treating lung cancer. Epigenetic therapy may circumvent the problems of tumor heterogeneity and drug resistance by affecting the expression of several hundred target genes. This review highlights precision medicine using an innovative approach of epigenetic priming prior to conventional standard therapy or targeted cancer therapy in lung cancer.

Insulin Receptor Isoforms in Physiology and Disease: An Updated View

The insulin receptor (IR) gene undergoes differential splicing that generates two IR isoforms, IR-A and IR-B. The physiological roles of IR isoforms are incompletely understood and appear to be determined by their different binding affinities for insulin-like growth factors (IGFs), particularly for IGF-2. Predominant roles of IR-A in prenatal growth and development and of IR-B in metabolic regulation are well established. However, emerging evidence indicates that the differential expression of IR isoforms may also help explain the diversification of insulin and IGF signaling and actions in various organs and tissues by involving not only different ligand-binding affinities but also different membrane partitioning and trafficking and possibly different abilities to interact with a variety of molecular partners. Of note, dysregulation of the IR-A/IR-B ratio is associated with insulin resistance, aging, and increased proliferative activity of normal and neoplastic tissues and appears to sustain detrimental effects. This review discusses novel information that has generated remarkable progress in our understanding of the physiology of IR isoforms and their role in disease. We also focus on novel IR ligands and modulators that should now be considered as an important strategy for better and safer treatment of diabetes and cancer and possibly other IR-related diseases.

MiR-195 suppresses the metastasis and epithelial-mesenchymal transition of hepatocellular carcinoma by inhibiting YAP

MiR-195, a novel cancer-related microRNA, was previously reported to play an important role in many malignancies. This study aimed to investigate the role of miR-195 mediated epithelial-mesenchymal transition (EMT) and the progression of hepatocellular carcinoma (HCC) as well as the underlying mechanisms. Our result demonstrated that miR-195 were significantly down regulated in HCC and its decreased expression is associated with poor clinical features of HCC patients. Oppositely, expression level of YAP was significantly higher in HCC tissues, and the level of YAP in metastatic tissues was significantly higher. We also found that a strong inversely association between low level expression of miR-195 and high level of YAP in HCC tissues. Notably, this study confirmed that miR-195, YAP and their combination were valuable predictors for the prognosis of HCC patients. We also explored that miR-195 inhibits HCC growth and metastatic capacity. Mechanistically, we confirm that miR-195 inhibits the migration, invasion and EMT of HCC cells by suppressing YAP. Lastly, we revealed YAP was not only the downstream of miR-195 in HCC, but also mediated the promoting effects of miR-195 on the metastasis and EMT of HCC cells. Taken together, miR-195 inhibits the metastasis and EMT in HCC by targeting YAP. MiR-195/YAP pathway may potentially act as novel biomarker and attractive therapeutic target in HCC.

miR-125a-5p upregulation suppresses the proliferation and induces the cell apoptosis of lung adenocarcinoma by targeting NEDD9

MicroRNAs (miRNAs) are critical translational regulators that act as oncogenes or tumor-suppressor genes. qRT-PCR assay results showed that the expression levels of miR-125a-5p are lower in lung adenocarcinoma (AD) tissues than expression levels in adjacent non-neoplastic tissues. This relative expression was found to be significantly associated with lymph node metastases. Cell growth, apoptosis, caspase activity and Transwell invasion assay results showed that in two lung adenocarcinoma cell lines transfected with a miR-125a-5p mimic, proliferation and invasion rates were found to be significantly reduced, whereas the apoptosis rate of the miR-125a-5p mimic group was enhanced. Subsequent western blotting and luciferase reporter assays showed that miR-125a-5p is able to bind to putative binding sites within the mRNA 3' untranslated region (UTR) of neural precursor cell expressed, developmentally downregulated 9 (NEDD9). Our findings suggest that miR-125a-5p may serve as a therapeutic agent for lung adenocarcinoma through its major target, NEDD9.

MicroRNA-195 inhibits the behavior of cervical cancer tumors by directly targeting HDGF

MicroRNAs (miRNAs/miRs) are a class of conserved non-coding endogenous small regulatory RNAs that regulate target gene expression by binding to the 3′-untranslated region of target mRNAs in a base-pairing manner, resulting in repression of transcription or degradation of target mRNAs. It has been demonstrated previously that the abnormal expression of miRNAs is involved in the carcinogenesis and progression of cervical cancer. The aim of the present study was to investigate the expression, biological functions and underlying molecular mechanisms of miR-195 in cervical cancer. The reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression level of miR-195 in cervical cancer tissues and cell lines. Following transfection, an MTT assay, cell migration and invasion assays, western blot analysis and a dual-luciferase reporter assay were performed in human cervical cancer cells. In the present study, it was identified that miR-195 was downregulated in cervical cancer tissues and cell lines. Additionally, upregulation of miR-195 and knockdown of hepatoma-derived growth factor (HDGF) inhibited proliferation, migration and invasion of cervical cancer cells. Furthermore, a dual-luciferase reporter assay identified that HDGF was a direct target gene of miR-195. RT-qPCR and western blot analysis demonstrated that miR-195 mimic inhibited HDGF expression at the mRNA and protein levels, whereas miR-195 inhibitor enhanced HDGF expression at the mRNA and protein levels. These results indicated that miR-195 targeted HDGF to inhibit the behavior of tumors in cervical cancer. These results also suggested that miR-195 was a potential therapeutic biomarker of cervical cancer.

MicroRNA-592 targets IGF-1R to suppress cellular proliferation, migration and invasion in hepatocellular carcinoma

MicroRNAs (miRs) can function as tumor suppressors or oncogenes in different types of human malignancy, and may provide an effective therapy for cancer. The expression and functions of miR-592 have previously been studied in relation to cancer. However, the expression and potential functions of miR-592 in hepatocellular carcinoma (HCC) are still unknown. Using quantitative polymerase chain reaction, MTT assays, cellular migration and invasion assays, bioinformatics software, western blot analysis and dual-luciferase report assays, the present study explored the expression and roles of miR-592 in HCC. It was identified that miR-592 was significantly downregulated in HCC tissues and cell lines. The statistical analysis revealed that low expression of miR-592 was evidently associated with tumor node metastasis stage and lymph node metastasis. Additionally, the present study provided the first evidence that miR-592 was likely to directly target the insulin-like growth factor 1 receptor in vitro. The present results indicated that miR-592 could be investigated as an efficacious therapeutic target for HCC in the future.

miR-195 inhibits cell proliferation via targeting AEG-1 in hepatocellular carcinoma

Emerging evidence has indicated that microRNAs (miRNAs) are frequently dysregulated and are fundamental in the pathogenesis of hepatocellular carcinoma (HCC). However, the roles of miR-195 in HCC have not been well elucidated. In the present study, the expression of miR-195 was determined to be markedly downregulated in HCC tissues and cell lines, as compared with normal liver cells. Restoration of miR-195 expression resulted in significant inhibition of the proliferation and tumorigenicity of HCC cells in vitro and in vivo. Gene expression data and luciferase reporter assays revealed that miR-195 is able to directly inhibit the expression of astrocyte elevated gene 1 (AEG-1) through interaction with its 3′ untranslated region. Consistently, an inverse correlation between miR-195 and AEG-1 expression was observed in HCC tissues. Furthermore, the overexpression of AEG-1 was able to partially attenuate the miR-195-induced inhibition of cell growth and promotion of apoptosis. Taken together, these findings indicate that miR-195 functions as a tumor suppressor by inhibiting AEG-1. This pathway may provide new insights into the potential molecular mechanisms of HCC.

miR-195 in human primary mesenchymal stromal/stem cells regulates proliferation, osteogenesis and paracrine effect on angiogenesis

Mesenchymal Stromal/Stem Cells (MSC) are currently being explored in diverse clinical applications, including regenerative therapies. Their contribution to regeneration of bone fractures is dependent on their capacity to proliferate, undergo osteogenesis and induce angiogenesis. This study aimed to uncover microRNAs capable of concomitantly regulate these mechanisms. Following microRNA array results, we identified miR-195 and miR-497 as downregulated in human primary MSC under osteogenic differentiation. Overexpression of miR-195 or miR-497 in human primary MSC leads to a decrease in osteogenic differentiation and proliferation rate. Conversely, inhibition of miR-195 increased alkaline phosphatase expression and activity and cells proliferation. Then, miR-195 was used to study MSC capacity to recruit blood vessels in vivo. We provide evidence that the paracrine effect of MSC on angiogenesis is diminishedwhen cells over-express miR-195. VEGF may partially mediate this effect, as its expression and secreted protein levels are reduced by miR-195, while increased by anti-miR-195, in human MSC. Luciferase reporter assays revealed a direct interaction between miR-195 and VEGF 3′-UTR in bone cancer cells. In conclusion, our results suggest that miR-195 regulates important mechanisms for bone regeneration, specifically MSC osteogenic differentiation, proliferation and control of angiogenesis; therefore, it is a potential target for clinical bone regenerative therapies.

miR-195 Inhibits EMT by Targeting FGF2 in Prostate Cancer Cells

Prostate cancer (PCa) is one of the leading causes of deaths in America. The major cause of mortality can be attributed to metastasis. Cancer metastasis involves sequential and interrelated events. miRNAs and epithelial-mesenchymal transition (EMT) are implicated in this process. miR-195 is downregulated in many human cancers. However, the roles of miR-195 in PCa metastasis and EMT remain unclear. In this study, data from Memorial Sloan Kettering Cancer Center (MSKCC) prostate cancer database were re-analysed to detect miR-195 expression and its roles in PCa. miR-195 was then overexpressed in castration-resistant PCa cell lines, DU-145 and PC-3. The role of miR-195 in migration and invasion in vitro was also investigated, and common markers in EMT were evaluated through Western blot analysis. A luciferase reporter assay was conducted to confirm the target gene of miR-195; were validated in PCa cells. In MSKCC data re-analyses, miR-195 was poorly expressed in metastatic PCa; miR-195 could be used to diagnose metastatic PCa by measuring the corresponding expression. Area under the receiver operating characteristic curve (AUC-ROC) was 0.705 (P = 0.017). Low miR-195 expression was characterised with a shorter relapse-free survival (RFS) time. miR-195 overexpression suppressed cell migration, invasion and EMT. Fibroblast growth factor 2 (FGF2) was confirmed as a direct target of miR-195. FGF2 knockdown also suppressed migration, invasion and EMT; by contrast, increased FGF2 partially reversed the suppressive effect of miR-195. And data from ONCOMINE prostate cancer database showed that PCa patients with high FGF2 expression showed shorter RFS time (P = 0.046). Overall, this study demonstrated that miR-195 suppressed PCa cell metastasis by downregulating FGF2. miR-195 restoration may be considered as a new therapeutic method to treat metastatic PCa.

miR-195 is a key regulator of Raf1 in thyroid cancer

Proto-oncogene Raf1 serves as a part of the mitogen-activated protein kinases/extracellular signal-regulated kinase signal transduction pathway and regulates cell migration, apoptosis, and differentiation. Although a large number of studies have shown that Raf1 is overexpressed in various kinds of cancer, little is known about the association between Raf1 and miRNAs in thyroid carcinoma. This study proves that Raf1 is overexpressed in thyroid cancer, which has been confirmed by many other studies. Besides, we identify that Raf1 is a direct target of miR-15a/b, miR-16, and miR-195 by dual luciferase reporter assay. We also find that the expression of miR-195 is downregulated in 50 pairs of thyroid tumor tissues compared to the adjacent nontumor tissues, while there is no difference in the expression of miR-15a/b and miR-16 between the groups. Furthermore, exogenous overexpression of miR-195 significantly inhibits the protein expression of Raf1 and blocks the thyroid cancer cell proliferation. Our findings delineate a novel mechanism for the regulation of Raf1 in thyroid cancer, which may help to provide a new direction for the treatment of thyroid cancer.

Regulation of IGF -1 signaling by microRNAs

The insulin-like growth factor 1 (IGF-1) signaling pathway regulates critical biological processes including development, homeostasis, and aging. Dysregulation of this pathway has been implicated in a myriad of diseases such as cancers, neurodegenerative diseases, and metabolic disorders, making the IGF-1 signaling pathway a prime target to develop therapeutic and intervention strategies. Recently, small non-coding RNA molecules in ∼22 nucleotide length, microRNAs (miRNAs), have emerged as a new regulator of biological processes in virtually all organ systems and increasing studies are linking altered miRNA function to disease mechanisms. A miRNA binds to 3'UTRs of multiple target genes and coordinately downregulates their expression, thereby exerting a profound influence on gene regulatory networks. Here we review the components of the IGF-1 signaling pathway that are known targets of miRNA regulation, and highlight recent studies that suggest therapeutic potential of these miRNAs against various diseases.

MicroRNA-27b suppresses growth and invasion of NSCLC cells by targeting Sp1

Non-small cell lung cancer (NSCLC) is the major cause of cancer death worldwide. Increasing evidence shows that microRNAs (miRNAs), evolutionally conserved non-coding RNAs, are widely involved in the development and progression of NSCLC. Aberrant alteration of miRNAs expression has been implicated in NSCLC initiation and progression. Herein, we studied the role of miR-27b in NSCLC cells. We found that miR-27b was significantly decreased in several NSCLC cell lines. Forced overexpression of miR-27 inhibited both the growth and invasion of NSCLC cells. Furthermore, we identified Sp1 transcription factor (Sp1) as a target of miR-27b in NSCLC cells. Moreover, we found that miR-27 suppressed growth and invasion of NSCLC cells partially by targeting Sp1. Our data indicate that miR-27b may play a critical role in the development of NSCLC.