MicroRNA-376c Inhibits Cell Proliferation and Invasion in Osteosarcoma by Targeting to Transforming Growth Factor-Alpha

MicroRNAs as the pivotal regulators of cisplatin resistance in osteosarcoma

Osteosarcoma (OS) is an aggressive bone tumor that originates from mesenchymal cells. It is considered as the eighth most frequent childhood cancer that mainly affects the tibia and femur among the teenagers and young adults. OS can be usually diagnosed by a combination of MRI and surgical biopsy. The intra-arterial cisplatin (CDDP) and Adriamycin is one of the methods of choices for the OS treatment. CDDP induces tumor cell death by disturbing the DNA replication. Although, CDDP has a critical role in improving the clinical complication in OS patients, a high ratio of CDDP resistance is observed among these patients. Prolonged CDDP administrations have also serious side effects in normal tissues and organs. Therefore, the molecular mechanisms of CDDP resistance should be clarified to define the novel therapeutic modalities in OS. Multidrug resistance (MDR) can be caused by various cellular and molecular processes such as drug efflux, detoxification, and signaling pathways. MicroRNAs (miRNAs) are the key regulators of CDDP response by the post transcriptional regulation of target genes involved in MDR. In the present review we have discussed all of the miRNAs associated with CDDP response in OS cells. It was observed that the majority of reported miRNAs increased CDDP sensitivity in OS cells through the regulation of signaling pathways, apoptosis, transporters, and autophagy. This review highlights the miRNAs as reliable non-invasive markers for the prediction of CDDP response in OS patients.

Immune-Associated Gene Signatures Serve as a Promising Biomarker of Immunotherapeutic Prognosis for Renal Clear Cell Carcinoma

As the most common type of renal cell carcinoma (RCC), the renal clear cell carcinoma (ccRCC) is highly malignant and insensitive to chemotherapy or radiotherapy. Although systemic immunotherapies have been successfully applied to ccRCC in recent years, screening for patients who can benefit most from these therapies is still essential and challenging due to immunological heterogeneity of ccRCC patients. To this end, we implemented a series of deep investigation on the expression and clinic data of ccRCC from The Cancer Genome Atlas (TCGA) International Consortium for Cancer Genomics (ICGC). We identified a total of 946 immune-related genes that were differentially expressed. Among them, five independent genes, including SHC1, WNT5A, NRP1, TGFA, and IL4R, were significantly associated with survival and used to construct the immune-related prognostic differential gene signature (IRPDGs). Then the ccRCC patients were categorized into high-risk and low-risk subgroups based on the median risk score of the IRPDGs. IRPDGs subgroups displays distinct genomic and immunological characteristics. Known immunotherapy-related genes show different mutation burden, wherein the mutation rate of VHL was higher than 40% in the two IRPDGs subgroups, and SETD2 and BAP1 mutations differed most between two groups with higher frequency in the high-risk subgroup. Moreover, IRPDGs subgroups had different abundance in tumor-infiltrating immune cells (TIICs) with distinct immunotherapy efficacy. Plasma cells, regulatory cells (Tregs), follicular helper T cells (Tfh), and M0 macrophages were enriched in the high-risk group with a higher tumor immune dysfunction and rejection (TIDE) score. In contrast, the low-risk group had abundant M1 macrophages, mast cell resting and dendritic cell resting infiltrates with lower TIDE score and benefited more from immune checkpoint inhibitors (ICI) treatment. Compared with other biomarkers, such as TIDE and tumor inflammatory signatures (TIS), IRPDGs demonstrated to be a better biomarker for assessing the prognosis of ccRCC and the efficacy of ICI treatment with the promise in screening precise patients for specific immunotherapies.

P2X7 promotes metastatic spreading and triggers release of miRNA-containing exosomes and microvesicles from melanoma cells

Tumor growth and metastatic spreading are heavily affected by the P2X7 receptor as well as microvesicles and exosomes release into the tumor microenvironment. P2X7 receptor stimulation is known to trigger vesicular release from immune and central nervous system cells. However, P2X7 role in microvesicles and exosomes delivery from tumor cells was never analyzed in depth. Here we show that P2X7 is overexpressed in patients affected by metastatic malignant melanoma and that its expression closely correlates with reduced overall survival. Antagonism of melanoma cell-expressed P2X7 receptor inhibited in vitro anchorage-independent growth and migration and in vivo dissemination and lung metastasis formation. P2X7 stimulation triggered the release of miRNA-containing microvesicles and exosomes from melanoma cells, profoundly altering the nature of their miRNA content, as well as their dimensions and quantity. Among the more than 200 miRNAs that we found up-or-down-modulated for each vesicular fraction tested, we identified three miRNAs, miR-495-3p, miR-376c-3p, and miR-6730-3p, that were enriched in both the exosome and microvesicle fraction in a P2X7-dependent fashion. Interestingly, upon transfection, these miRNAs promoted melanoma cell growth or migration, and their vesicular release was minimized by P2X7 antagonism. Our data unveil an exosome/microvesicle and miRNA-dependent mechanism for the pro-metastatic activity of the P2X7 receptor and highlight this receptor as a suitable prognostic biomarker and therapeutic target in malignant melanoma.

LncRNA BCRT1 facilitates osteosarcoma progression via regulating miR-1303/FGF7 axis

Growing studies noted that lncRNA was closely related with the initiation and progression of tumors. However, the role of BCRT1 in the progression of osteosarcoma remains unknown. We noted that BCRT1 is significantly upregulated in osteosarcoma specimens and cells. Elevated expression of BCRT1 promotes cell growth and cell cycle in osteosarcoma cell. Moreover, BCRT1 induces EMT and secretion of inflammatory mediators in osteosarcoma cell. We illustrated that elevated expression of BCRT1 decreases miR-1303 expression in MG-63 cell. The expression of miR-1303 is lower in osteosarcoma specimens than in non-tumor specimens. There is an inverse interrelation between miR-1303 levels and BCRT1 levels in osteosarcoma specimens. Furthermore, we identified FGF7 is one direct target gene of miR-1303 in osteosarcoma cell. Ectopic expression of miR-1303 suppresses FGF7 expression and elevated expression of BCRT1 enhanced FGF7 expression in MG-63 cell. Finally, we illustrated that BCRT1 induces osteosarcoma cell cycle and proliferation and promotes EMT progression and inflammatory mediators secretion via modulating FGF7 expression. Our study suggested that BCRT1 acts as one oncogene in osteosarcoma progression.

Cisplatin inhibits the proliferation of Saos-2 osteosarcoma cells via the miR-376c/TGFA pathway

The transforming growth factor alpha (TGFA) gene is involved in the proliferation and metastasis of various tumors, but its role in cell sensitivity to cisplatin chemotherapy is unclear. In this study, we investigated the mechanism underlying inhibitory effects of cisplatin on growth and proliferation of osteosarcoma cells. Osteosarcoma and normal skeletal muscle tissues were collected from 26 patients by biopsy. TGFA was silenced or overexpressed in Saos-2 osteosarcoma cells by transfection with TGFA-shRNA or TGFA ORF clone, respectively. MiR-376c was inhibited or overexpressed by transfection of Saos-2 cells with miR-376c sponge or miR-376c mimics, respectively. Cell growth was analyzed by MTT assay and cell proliferation by BrdU assay. MiR-376c and TGFA mRNA expression was detected by quantitative reverse transcription PCR and TGFA protein expression by Western blot. The target relationship between miR-376c and TGFA was assessed by luciferase reporter assay. Both in osteosarcoma tissues and Saos-2 cells, miR-376c expression was significantly decreased and TGFA mRNA expression was significantly increased compared with control. Transfection of Saos-2 cells with TGFA-shRNA silenced TGFA expression and significantly inhibited cell growth and proliferation. TGFA mRNA and protein expression in Saos-2 cells significantly decreased with increasing cisplatin concentrations (2.5–10 mg/L). Transfection with TGFA ORF clone reversed the inhibitory effects of cisplatin on Saos-2 cell proliferation. Compared with cisplatin (10 mg/L) treatment alone, the combined treatment with cisplatin and miR-376c mimics inhibited the proliferation of Saos-2 cells more significantly. MiR-376c suppressed TGFA expression by directly interacting with its 3’ UTR region. Overall, cisplatin inhibited the proliferation of Saos-2 cells by upregulating miR-376c and downregulating TGFA expression.

Circular RNA TAF4B Promotes Bladder Cancer Progression by Sponging miR-1298-5p and Regulating TGFA Expression

BACKGROUND

Bladder cancer (Bca) is the most common malignant tumor of the urinary system. Circular RNAs (circRNAs) have been recognized as key regulators in tumorigenesis. However, the molecular mechanisms underlying circRNAs involved in the progression of BCa remain largely unknown.

METHODS

We detected the expression level of circular RNA TAF4B (circTAF4B) by qRT-PCR assay. Cell proliferation was evaluated by CCK-8 and colony formation assays. Wound healing and Transwell assays were performed to measure cell migration and invasion capability. Moreover, we performed qRT-PCR and western blotting assays to determine the expression levels of epithelial-mesenchymal transition (EMT) markers. A nuclear/cytoplasmic fractionation assay was used to measure the subcellular location of circTAF4B. RNA pull-down and dual-luciferase reporter assays were used to detect the target microRNA of circTAF4B. A mouse xenograft model was produced to analyze the effect of circTAF4B on the tumorigenesis of BCa.

RESULTS

In this study, we identified a novel circular RNA, circTAF4B, that is significantly upregulated in BCa and correlated with poor prognosis. Downregulated circTAF4B abolished the growth, metastasis and EMT process in BCa cells. Mechanistically, we found that circTAF4B facilitated the expression of transforming growth factor A (TGFA) by sponging miR-1298-5p. Finally, circTAF4B enhanced the proliferation and EMT process of BCa cells in vivo.

CONCLUSION

In summary, our study demonstrated that circTAF4B played a carcinogenic role in the growth, metastasis, and EMT process of BCa by regulating the miR-1298-5p/TGFA axis. Thus, circTAF4B may become a diagnostic and therapeutic target for BCa.

miRNA signatures in childhood sarcomas and their clinical implications

Progresses in multimodal treatments have significantly improved the outcomes for childhood cancer. Nonetheless, for about one-third of patients with Ewing sarcoma, rhabdomyosarcoma, or osteosarcoma steady remission has remained intangible. Thus, new biomarkers to improve early diagnosis and the development of precision-targeted medicine remain imperative. Over the last decade, remarkable progress has been made in the basic understanding of miRNAs function and in interpreting the contribution of their dysregulation to cancer development and progression. On this basis, this review focuses on what has been learned about the pivotal roles of miRNAs in the regulation of key genes implicated in childhood sarcomas.

MicroRNA-23a promotes colorectal cancer cell survival by targeting PDK4

MicroRNA (miR) is important regulators of gene expression, and aberrant miR expression has been linked to oncogenesis; however, little is understood about their contribution to colorectal cancer (CRC). Here, we determined that miR-23a is overexpressed in human colorectal cancer cell lines and tissues compared with that of normal cells. The stable over-expression of miR-23a in CRC cells was sufficient to promote cell proliferation in vitro and in vivo. Further studies showed that miR-23a can directly bind to the 3'untranslated region (3'UTR) of PDK4 mRNA and subsequently repress both the mRNA and protein expressions of PDK4. PDK4 negatively regulate CRC proliferation via suppressing PDH activity. Ectopic expression of PDK4 by transiently transfected with PDK4 vector encoding the entire coding sequence could reverse the effects of miR-23a on CRC proliferation. By this way, miR-23a promotes PDH activation and oxidative phosphorylation to generate sufficient ATP for cell proliferation. Our results illustrated that the up-regulation of miR-23a played an important role in CRC cell proliferation through direct repressing PDK4, suggesting a potential application of miR-23a in prognosis prediction and therapeutic application in CRC.

MicroRNA-376c-3p Facilitates Human Hepatocellular Carcinoma Progression via Repressing AT-Rich Interaction Domain 2

Hepatocellular carcinoma (HCC), accounting for approximately 90% of liver cancer, is the most lethal malignant tumors in the world. Large amount of evidence indicate that microRNAs (miRNAs) contribute to the tumorigenesis and progression of HCC. Among them, miR-376c-3p was recently identified as a tumor-related miRNA and is up-regulated in HBV-related HCC. But, the clinical significance of miR-376c-3p and its biological function in HCC progression are still unclear. Here, we confirmed that miR-376c-3p expression level in HCC was markedly higher than that in noncancerous tissues. Up-regulation of miR-376c-3p was detected in four different HCC cell lines. High miR-376c-3p expression correlated with poor prognostic features, such as large tumor size and venous infiltration. Follow-up data indicated that high miR-376c-3p level evidently correlated with poor clinical outcomes of HCC patients. Moreover, knockdown of miR-376c-3p repressed HCC cell growth, migration and invasion in vitro. miR-376c-3p overexpression facilitated these malignant behaviors of Bel-7402 cells. Mechanistically, miR-376c-3p posttranscriptionally repressed ARID2 expression by directly interacting with its 3'-UTR. Furthermore, an obvious negative correlation between miR-376c-3p and ARID2 mRNA expression in HCC tissues was confirmed. Notably, miR-376c-3p knockdown suppressed HCC growth and metastasis in nude mice. Gain-of-function experiments showed that ARID2 inhibited cell growth and mobility of Hep3B cells. Subsequently, ARID2 knockdown rescued miR-376c-3p silencing attenuated Hep3B cell proliferation and mobility. Our results suggest that miR-376c-3p exerts an oncogenic role in HCC progression.

Relationship between Altered miRNA Expression and DNA Methylation of the DLK1-DIO3 Region in Azacitidine-Treated Patients with Myelodysplastic Syndromes and Acute Myeloid Leukemia with Myelodysplasia-Related Changes

The DLK1–DIO3 region contains a large miRNA cluster, the overexpression of which has previously been associated with myelodysplastic syndromes (MDS). To reveal whether this overexpression is epigenetically regulated, we performed an integrative analysis of miRNA/mRNA expression and DNA methylation of the regulatory sequences in the region (promoter of the MEG3 gene) in CD34+ bone marrow cells from the patients with higher-risk MDS and acute myeloid leukemia with myelodysplasia-related changes (AML-MRC), before and during hypomethylating therapy with azacytidine (AZA). Before treatment, 50% of patients showed significant miRNA/mRNA overexpression in conjunction with a diagnosis of AML-MRC. Importantly, increased level of MEG3 was associated with poor outcome. After AZA treatment, the expression levels were reduced and were closer to those seen in the healthy controls. In half of the patients, we observed significant hypermethylation in a region preceding the MEG3 gene that negatively correlated with expression. Interestingly, this hypermethylation (when found before treatment) was associated with longer progression-free survival after therapy initiation. However, neither expression nor methylation status were associated with future responsiveness to AZA treatment. In conclusion, we correlated expression and methylation changes in the DLK1–DIO3 region, and we propose a complex model for regulation of this region in myelodysplasia.

Hsa-miR-376c-3p targets Cyclin D1 and induces G1-cell cycle arrest in neuroblastoma cells

High-risk neuroblastoma is the most aggressive form of cancer in children. The estimated survival of children with high-risk neuroblastoma is 40-50% compared with low and intermediate risk neuroblastoma, which is >98 and 90-95%, respectively. In addition, patients with high-risk neuroblastoma often experience relapse following intensive treatments with standard chemotherapeutic drugs. Therefore alternative strategies are required to address this problem. MicroRNAs (miRNAs/miRs) are small, endogenously expressed non-coding RNAs, which when deregulated have been demonstrated to serve significant roles in the tumorigenesis of a number of different types of cancer. Results from a previous deep sequencing study identified 22 downregulated miRNAs from the 14q32 miRNA cluster differentially expressed in neuroblastoma cell lines isolated from 6 patients at diagnosis and at relapse following intensive treatments. miR-376c-3p is one of the 22 miRNAs that was downregulated in the majority of the cell lines isolated from patients post treatment. The present study employed reverse transcription-quantitative polymerase chain reaction (RT-qPCR) to quantify the basic expression of miR-376c-3p in 6 neuroblastoma cell lines. The functional role of miR-376c-3p in the neuroblastoma cell lines was evaluated by alamar blue-cell viability and propidium iodide-flow cytometric assays. In addition, luciferase reporter assays, RT-qPCR and western blotting were performed to identify and quantify the targets of miR-376c-3p in neuroblastoma cell lines. Ectopic expression of miR-376c-3p led to significant inhibition of cell viability and G1-cell cycle arrest in multiple neuroblastoma cell lines by reducing the expression of cyclin D1, an oncogene critical for neuroblastoma pathogenesis. The results of the present study provide novel insights into the functional role of miR-376c-3p and suggest new approaches for the treatment of neuroblastoma.

Serum microRNA-376 family as diagnostic and prognostic markers in human gliomas

BACKGROUND

MicroRNA (miR)-376 family play crucial roles in cancer formation and progression.

OBJECTIVE

To investigate expression patterns of circulating miR-376 members in glioma patients, and to explore their diagnostic and prognostic values.

METHODS

Expression of miR-376 members in serum samples from 100 glioma patients and 50 healthy controls were detected by quantitative real-time PCR.

RESULTS

Serum miR-376a, miR-376b and miR-376c in glioma patients were significantly lower than those in healthy controls (all P< 0.05). Their expression could efficiently distinguish the glioma patients from healthy controls according to the receiver operating characteristic (ROC) analysis [for miR-376a, the area under ROC curve (AUC) = 0.872, the optimal cut-off value = 1.95, the sensitivity = 81.0% and the specificity = 82.0%; for miR-376b, AUC = 0.890, the optimal cut-off value = 2.07, the sensitivity = 82.0% and the specificity = 78.0%; for miR-376c, AUC = 0.837, the optimal cut-off value = 2.12, the sensitivity = 90.0% and the specificity = 70.0%; all P<0. 001]. Decreased expression of miR-376a, miR-376b and miR-376c in patients' sera were significantly associated with advanced WHO grade (all P< 0.01) and low KPS (all P< 0.05). Kaplan-Meier and Cox regression analyses showed that low miR-376a, miR-376b and miR-376c expression, and high grade were all independent factors predicting poor outcome of glioma patients. Notably, subgroup analyses showed that serum miR-376a, miR-376b and miR-376c levels had more significant prognostic values in patients with high grade gliomas than those with low grade gliomas.

CONCLUSIONS

Aberrant expression of the miR-376 family may be involved into tumorigenesis and tumor progression of human gliomas. Circulating miR-376a, miR-376b and miR-376c may be promising non-invasive biomarkers for diagnosis and prognosis in glioma patients.

MALAT1 promotes osteosarcoma development by targeting TGFA via MIR376A

Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is a long non-coding RNA (lncRNA) that contributes to the initiation and development of many solid tumors, including osteosarcoma (OS). Here, we showed that MALAT1 was increased in human OS cell lines and tissues and promoted OS cell growth, while MALAT1 knockdown suppressed OS cell growth. We also detected downregulation of MIR376A, a suppressor of OS growth, and upregulation of TGFA, a promoter of OS growth, in OS tissues. TGFA expression was positively correlated with MALAT1 expression, and both were negatively correlated with MIR376A expression. There was a direct interaction between MIR376A and MALAT1 via a putative MIR376A binding site within the MALAT1 3′-untranslated region (3′-UTR). There was also a direct interaction between MIR376A and the TGFA 3′-UTR. Thus, MALAT1 may promote OS cell growth through inhibition of MIR376A, leading to increased expression of TGFA. Our results suggest a MALAT1/MIR376A/TGFA axis mediates OS cell proliferation and tumor progression.

MiR 376c inhibits osteoblastogenesis by targeting Wnt3 and ARF-GEF-1 -facilitated augmentation of beta-catenin transactivation

Wnt signaling pathway plays important role in all aspects of skeletal development which include chondrogenesis, osteoblastogenesis, and osteoclastogenesis. Induction of the Wnt-3 signaling pathway promotes bone formation while inactivation of the pathway leads to bone related disorders like osteoporosis. Wnt signaling thus has become a desired target to treat osteogenic disorders. MicroRNAs (miRNAs) represent an important category of elements that interact with Wnt signaling molecules to regulate osteogenesis. Here, we show that miR-376c, a well-characterized tumor suppressor which inhibits cell proliferation and invasion in osteosarcoma by targeting to transforming growth factor-alpha, suppresses osteoblast proliferation, and differentiation. Over-expression of miR-376c inhibited osteoblast differentiation, whereas inhibition of miR-376c function by antimiR-376c promoted expression of osteoblast-specific genes, alkaline phosphatase (ALP) activity, and matrix mineralization. Target prediction analysis tools and experimental validation by luciferase 3' UTR reporter assay along with qRT-PCR identified Wnt-3 and ARF-GEF-1 as direct targets of miR-376c. It was seen that over-expression of miR-376c leads to repression of canonical Wnt/β-catenin signaling. Our overall results suggest that miR-376c targets Wnt-3 and ARF-GEF-1 suppresses ARF-6 activation which prevents the release of β-catenin and its transactivation thereby inhibiting osteoblast differentiation. Although miR-376c is known to be a tumor repressor; we have identified a second complementary function of miR-376c where it inhibits Wnt-3-mediated osteogenesis and promotes bone loss.

Multitype Network-Guided Target Controllability in Phenotypically Characterized Osteosarcoma: Role of Tumor Microenvironment

This study highlights the relevance of network-guided controllability analysis as a precision oncology tool. Target controllability through networks is potentially relevant to cancer research for the identification of therapeutic targets. With reference to a recent study on multiple phenotypes from 22 osteosarcoma (OS) cell lines characterized both in vitro and in vivo, we found that a variety of critical proteins in OS regulation circuits were in part phenotype specific and in part shared. To generalize our inference approach and match cancer phenotypic heterogeneity, we employed multitype networks and identified targets in correspondence with protein sub-complexes. Therefore, we established the relevance for diagnostic and therapeutic purposes of inspecting interactive targets, namely those enriched by significant connectivity patterns in protein sub-complexes. Emerging targets appeared with reference to the OS microenvironment, and relatively to small leucine-rich proteoglycan members and D-type cyclins, among other collagen, laminin, and keratin proteins. These described were evidences shared across all phenotypes; instead, specific evidences were provided by critical proteins including IGFBP7 and PDGFRA in the invasive phenotype, and FGFR3 and THBS1 in the colony forming phenotype.

MiR-376c-3p regulates the proliferation, invasion, migration, cell cycle and apoptosis of human oral squamous cancer cells by suppressing HOXB7

PURPOSE

To test the influence of miR-376c-3p on the proliferation, invasion, migration, cell cycle and apoptosis of human oral squamous cancer cells (OSCC) and the relevant mechanism.

METHODS

We applied qRT-PCR and Western blot to compare the expression level of miR-376c-3p and HOXB7 in SCC-4, SCC-9, SCC-15, SCC-25 OSCC cell lines and 49 paired OSCC and normal oral epithelial tissue specimens were included in our present study. Also we analyzed the relative relationship of expression level between miR-376c-3p and HOXB7 in cancer tissues. Luciferase assay was used to confirm the target relationship between miR-376c-3p and HOXB7. Besides, MTT, Transwell, wound healing, colony formation and flow cytometer experiments were applied to evaluate the proliferation, cell viability, apoptosis, invasion and migration of transfected OSCC.

RESULTS

MiR-376c-3p was down-regulated while HOXB7 was up-regulated in OSCC tissues and cells than the normal ones. MiR-376c-3p directly targeted HOXB7 and reduced the expression of HOXB7. Overexpression of miR-376c-3p attenuated proliferation of SCC-9, SCC-15, SCC-24 and SCC-25 cells. Moreover, miR-376c-3p suppressed proliferation, viability, migration and invasion and induced G1/G0 arrest and cell apoptosis of SCC-25 cells. Besides, overexpression of HOXB7 efficiently abrogates these influences caused by overexpression of miR-376c-3p.

CONCLUSION

MiR-376c-3p suppresses the fission, proliferation, migration and invasion and induces cell apoptosis of OSCC via targeting HOXB7.

MicroRNA-610 suppresses osteosarcoma oncogenicity via targeting TWIST1 expression

Osteosarcoma is the most frequent primary bone tumor affects adolescents and young adults. Recently, microRNAs (miRNAs) are short, non-coding and endogenous RNAs that played as important roles in the initiation and progression of tumors. In this study, we try to explore the biological function and expression of miR-610 in the osteosarcoma. We showed that miR-610 expression was downregulated in the osteosarcoma tissues and cell lines. Elevated expression of miR-610 suppressed the osteosarcoma cell proliferation, cell cycle, invasion and EMT program. Moreover, overexpression of miR-610 increased sensitivity of MG-63 and U2OS cells to cisplatin. Twist1 was identified as a direct target gene of miR-610 in the osteosarcoma cell. Furthermore, we demonstrated that Twist1 was upregulated in the osteosarcoma tissues and cell lines. The expression of Twist1 was negatively associated with the expression of miR-610 expression in the osteosarcoma tissues. Ectopic expression of Twist1 inhibited the sensitivity of miR-610-overexpressing MG-63 cells to cisplatin. We also showed that overexpression of Twist1 increased the proliferation and invasion of miR-610-overexpressing MG-63 cells. These data indicated that ectopic expression of miR-610 suppressed the osteosarcoma cell proliferation, cell cylce, invasion and increased the sensitivity of osteosarcoma cells to cisplatin through targeting the Twist1 expression.

Thrombospondin-2 promotes prostate cancer bone metastasis by the up-regulation of matrix metalloproteinase-2 through down-regulating miR-376c expression

Background

Thrombospondin-2 (TSP-2) is a secreted matricellular glycoprotein that is found to mediate cell-to-extracellular matrix attachment and participates in many physiological and pathological processes. The expression profile of TSP-2 on tumors is controversial, and it up-regulates in some cancers, whereas it down-regulates in others, suggesting that the functional role of TSP-2 on tumors is still uncertain.

Methods

The expression of TSP-2 on prostate cancer progression was determined in the tissue array by the immunohistochemistry. The molecular mechanism of TSP-2 on prostate cancer (PCa) metastasis was investigated through pharmaceutical inhibitors, siRNAs, and miRNAs analyses. The role of TSP-2 on PCa metastasis in vivo was verified through xenograft in vivo imaging system.

Results

Based on the gene expression omnibus database and immunohistochemistry, we found that TSP-2 increased with the progression of PCa, especially in metastatic PCa and is correlated with the matrix metalloproteinase-2 (MMP-2) expression. Additionally, through binding to CD36 and integrin α_νβ₃, TSP-2 increased cell migration and MMP-2 expression. With inhibition of p38, ERK, and JNK, the TSP-2-induced cell migration and MMP-2 expression were abolished, indicating that the TSP-2’s effect on PCa is MAPK dependent. Moreover, the microRNA-376c (miR-376c) was significantly decreased by the TSP-2 treatment. Furthermore, the TSP-2-induced MMP-2 expression and the subsequent cell motility were suppressed upon miR-376c mimic stimulation. On the other hand, the animal studies revealed that the bone metastasis was abolished when TSP-2 was stably knocked down in PCa cells.

Conclusions

Taken together, our results indicate that TSP-2 enhances the migration of PCa cells by increasing MMP-2 expression through down-regulation of miR-376c expression. Therefore, TSP-2 may represent a promising new target for treating PCa.

Electronic supplementary material

The online version of this article (doi:10.1186/s13045-017-0390-6) contains supplementary material, which is available to authorized users.

The correlation between microRNA490-3p and TGFα in endometrial carcinoma tumorigenesis and progression

MicroRNAs (miRNAs) are small non-coding RNAs that negatively regulate the translation of messenger RNAs by binding their 3′-untranslated region (3′ UTR). MiR-490-3p has been reported to be a suppressor in various human cancers; however, little is known about the biological functions of miR-490-3p in endometrial cancer (EC). In our study, we found that MiR-490-3p mRNA expression was significantly lower in ECs than in normal endometrial tissues. MiR-490-3p mRNA expression was also negatively associated with depth of invasion (mucosa vs. muscular and serosa) and lymph node metastasis (negative vs. positive) in EC. MiR-490-3p overexpression reduced proliferation; promoted G1 arrest and apoptosis; suppressed migration and invasion; and reduced TGFα, NF-kB, cyclin D1, survivin, matrix metalloproteinase 2 (MMP2) mRNA and protein expression, and improved Bax mRNA and protein expression. The dual-luciferase reporter assay indicated that miR-490-3p directly targeted TGFα by binding its 3′ untranslated region. MiR-490-3P transfection also suppressed tumor development and TGFα expression (as determined by immunohistochemistry and western blotting) in vivo in the xenograft mouse model. This is the first demonstration that miR-490-3P might act as a suppressor in EC tumorigenesis and progression by targeting TGFα. Our results provide a theoretical basis for the further study on the molecular target for endometrial cancer.

Long noncoding RNA MALAT1-regulated microRNA 506 modulates ovarian cancer growth by targeting iASPP

MALAT1, an important cancer-associated long noncoding RNA (lncRNA), contributes to the development and progression of several cancers. Disordered expression of MALAT1 has been observed in several cancers, including cervical cancer, breast cancer, and ovarian cancer. However, the exact effects and molecular mechanisms of MALAT1 in ovarian cancer progression are still unknown. Here, we investigated the role of MALAT1 in human ovarian cancer cell lines and clinical tumor samples, in order to determine the function of this molecule. In our research, lncRNA-MALAT1 was specifically upregulated in ovarian cancer cell lines and promoted ovarian cancer-cell growth through targeting microRNA (miR)-506. Knockdown of MALAT1 inhibited the proliferation and DNA synthesis of human ovarian cancer cell in vitro. In addition, miR-506-dependent iASPP regulation was required in MALAT1-induced ovarian cancer-cell growth. These findings indicated that MALAT1 might suppress tumor growth via miR-506-dependent iASPP regulation. Taken together, our data indicated that MALAT1 might be an oncogenic lncRNA that promotes proliferation of ovarian cancer and could be regarded as a therapeutic target in human ovarian cancer.

miRNAs Related to Skeletal Diseases

miRNAs as non-coding, short, double-stranded RNA segments are important for cellular biological functions, such as proliferation, differentiation, and apoptosis. miRNAs mainly contribute to the inhibition of important protein translations through their cleavage or direct repression of target messenger RNAs expressions. In the last decade, miRNAs got in the focus of interest with new publications on miRNAs in the context of different diseases. For many types of cancer or myocardial damage, typical signatures of local or systemically circulating miRNAs have already been described. However, little is known about miRNA expressions and their molecular effect in skeletal diseases. An overview of published studies reporting miRNAs detection linked with skeletal diseases was conducted. All regulated miRNAs were summarized and their molecular interactions were illustrated. This review summarizes the involvement and interaction of miRNAs in different skeletal diseases. Thereby, 59 miRNAs were described to be deregulated in tissue, cells, or in the circulation of osteoarthritis (OA), 23 miRNAs deregulated in osteoporosis, and 107 miRNAs deregulated in osteosarcoma (OS). The molecular influences of miRNAs regarding OA, osteoporosis, and OS were illustrated. Specific miRNA signatures for skeletal diseases are described in the literature. Some overlapped, but also unique ones for each disease exist. These miRNAs may present useful targets for the development of new therapeutic approaches and are candidates for diagnostic evaluations.

miR-376c inhibits cervical cancer cell proliferation and invasion by targeting BMI1

MicroRNAs (miRNAs) play crucial roles in cancer development and progression. The purposes of this study were to explore the role of miR-376c in cervical cancer and to clarify the regulation of BMI1 by miR-376c. Quantitative RT-PCR was used to measure miR-376c expression in cervical cancer tissues and cell lines. The cell proliferation, cell cycle and Transwell invasion assays were performed. A luciferase reporter assay was conducted to confirm the target gene of miR-376c, and the results were validated in cervical cancer cell lines and tissues. MiR-376c was significantly downregulated in cervical cancer cell lines and clinical tissues. Upregulation of miR-376c impaired cell proliferation, blocked G1/S checkpoint of cell cycle and suppressed cell invasion in vitro. BMI1 was verified as a direct target of miR-376c, which was further confirmed by the inverse expression of miR-376c and BMI1 in patient specimens. The newly identified miR-376c/BMI1 pathway provides an insight into cervical cancer progression and may represent a novel therapeutic target.

MicroRNA-376c suppresses non-small-cell lung cancer cell growth and invasion by targeting LRH-1-mediated Wnt signaling pathway

MicroRNAs (miRNAs) that negatively regulate gene expression have emerged as novel therapeutic tools for cancer treatment. In this study, we investigated the potential role of Liver receptor homolog-1 (LRH-1), a novel oncogene, in non-small-cell lung cancer (NSCLC), and examined the regulation of LRH-1 by miRNAs. We found that LRH-1 was highly overexpressed in NSCLC cell lines. Knockdown of LRH-1 by small interfering RNA significantly inhibited NSCLC cell growth and invasion. miR-376c directly targeted the 3'-untranslated region (UTR) of LRH-1 and negatively regulated LRH-1 expression, as detected by dual-luciferase reporter assay, real-time quantitative polymerase chain reaction and Western blot analysis. Further data showed that miR-376c expression was inversely correlated with LRH-1 expression in clinical cancer samples. Overexpression of miR-376c could inhibit NSCLC cell growth and invasion as well as Wnt signaling. In contrast, depletion of miR-376c exhibited the opposite effects. Moreover, these effects of miR-376c overexpression were partially abrogated by overexpression of LRH-1. Taken together, these results indicate that LRH-1 is involved in regulating the growth and invasion of NSCLC cells and that miR-376c inhibits NSCLC cell growth and invasion by targeting LRH-1, providing a novel insight into the potential for development of anti-cancer drugs for NSCLC.

MiR-374a suppresses lung adenocarcinoma cell proliferation and invasion by targeting TGFA gene expression

Aberrant expression of miR-374a has been reported in several types of human cancers, including lung cancer. However, the functional significance and molecular mechanisms underlying the role of miR-374a in lung cancer remain largely unknown. We found that the expression of miR-374a was significantly downregulated in lung adenocarcinoma tissues compared to adjacent normal lung tissues in samples included in The Cancer Genome Atlas. Functional studies revealed that overexpression of miR-374a led to inhibition of lung adenocarcinoma cell proliferation, migration and invasion and that miR-374a negatively regulated transforming growth factor-alpha (TGFA) gene expression by directly targeting the 3'-UTR of TGFA mRNA. Treating lung adenocarcinoma cells with TGF-α neutralizing antibody resulted in suppression of cell proliferation and invasion, which mimicked the action of miR-374a. Additionally, TGFA gene expression was significantly higher in tumor tissues compared to adjacent normal tissue and high TGFA gene expression strongly correlated with poor survival in patients with lung adenocarcinoma. Taken together, our studies suggest that miR-374a suppresses lung adenocarcinoma cell proliferation and invasion via targeting TGFA gene expression. Our findings may provide novel treatment strategies for lung adenocarcinoma patients.

MicroRNA-505 functions as a tumor suppressor in endometrial cancer by targeting TGF-α

Background

Endometrial carcinoma (EC) is one of the most lethal gynecologic cancers. Patients frequently have regional or distant metastasis at diagnosis. MicroRNAs are small non-coding RNAs that participate in numerous biological processes. Recent studies have demonstrated that miR-505 is associated with several types of cancer; however, the expression and function of miR-505 have not been investigated in EC.

Methods

miR-505 expression in normal endometrial tissue, endometrial carcinomas were quantified by Quantitative reverse transcription PCR. The endometrial carcinoma cell lines HEC-1B and Ishikawa were each transfected with miR-505 or scrambled mimics, after which cell phenotype and expression of relevant molecules were assayed. Dual-luciferase reporter assay and a xenograft mouse model were used to examine miR-505 and its target gene TGF-α.

Results

RT-PCR results demonstrated that miR-505 was significantly downregulated in human EC tissues compared to normal endometrial tissues. Besides, miR-505 expression was negatively associated with FIGO stage (stage I-II vs. III-IV), and lymph node metastasis (negative vs. positive). In vitro, overexpression of miR-505 significantly suppressed EC cell proliferation, increased apoptosis and reduced migratory and invasive activity. A miR-505 binding site was identified in the 3′ untranslated region of TGF-α mRNA (TGFA) using miRNA target-detecting software; a dual luciferase reporter assay confirmed that miR-505 directly targets and regulates TGFA. RT-PCR and Western-blotting results indicated that overexpressing miR-505 reduced the expression of TGF-α and the TGF-α-regulated proteins MMP2, MMP9, CDK2, while induced Bax and cleaved-PARP expression in EC cells. In vivo, overexpression of miR-505 reduced the tumorigenicity and inhibited the growth of xenograft tumors in a mouse model of EC.

Conclusions

Taken together, this study demonstrates that miR-505 acts as tumor suppressor in EC by regulating TGF-α.

Electronic supplementary material

The online version of this article (doi:10.1186/s12943-016-0496-4) contains supplementary material, which is available to authorized users.

MicroRNA-23a enhances migration and invasion through PTEN in osteosarcoma

To investigate the biological significance of abundant microRNA-23a (miR-23a) expression in osteosarcoma and its correlation with PTEN in the pathogenesis of osteosarcoma migration and invasion. The human osteosarcoma cell lines MG63, HOS58 and SaoS-2, and the human normal osteoblasts (hFOB1.19) were grown in RPMI 1640 medium supplemented with 10% fetal bovine serum. Gene and protein levels of miR-23a and PTEN were examined to determine the molecular relationship between them in the pathogenesis of osteosarcoma. Inhibition of miR-23a effectively reduced migration and invasion of osteosarcoma cell lines. Bioinformatics and luciferase-reporter assay revealed that miR-23a specifically targeted the 3'-untranslational region of PTEN and regulated its expression. Downregulation of PTEN enhanced migration and invasion of osteosarcoma cell lines. Furthermore, in tumor tissues obtained from osteosarcoma patients, the expression of miR-23a was negatively correlated with PTEN and the high expression of miR-23a combined with low expression of PTEN might serve as a risk factor for cancer patients. Besides, miR-23a-mediated suppression of PTEN led to activation of AKT/ERK pathways and epithelial-mesenchymal transition (EMT) in osteosarcoma cells, and finally enhanced the activity of osteosarcoma cell proliferation and movement and promoted osteosarcoma xenograft tumor growth in mouse models. Our study showed that miR-23a, by downregulation of PTEN, enhanced migration and invasion in osteosarcoma cells.

P53 suppresses cell proliferation, metastasis, and angiogenesis of osteosarcoma through inhibition of the PI3K/AKT/mTOR pathway

OBJECTIVE

To investigate the role of P53 in the pathogenesis of osteosarcoma and the possible mechanism involved in it.

METHODS

The anti-proliferative effect of P53 was assessed using the cell counting Kit-8 assay. The migration and invasion potential were analyzed using wound-healing and transwell assays, respectively. The Matrigel capillary tube formation assay was performed to mimic in-vivo angiogenesis. Immunoblotting and immunofluorescence were used to observe protein levels and distribution of actin fibers. Finally, S2448p-mammalian target of rapamycin (mTOR) expression was detected on osteosarcoma tissues using immunohistochemistry.

RESULTS

Firstly, P53 potently inhibited cell proliferation in osteosarcoma cell line (MG63) and in human normal osteoblasts (hFOB1.19) in vitro at the IC50 ranged from 50 to 500 nmol/l. Then, an inhibitory effect of P53 on metastasis was observed in osteosarcoma cell line MG63, along with the cytoskeletal rearrangements and suppression of the phosphorylation of PI3K downstream factors including AKT and mTOR.

CONCLUSION

These results show that P53 suppresses cell proliferation and angiogenesis of osteosarcoma through inhibition of the PI3K/AKT/mTOR pathway, which might be an effective novel therapeutic candidate against osteosarcoma in the future.

Aberrant expression of the microRNA cluster in 14q32 is associated with del(5q) myelodysplastic syndrome and lenalidomide treatment

Lenalidomide is a novel thalidomide analogue with immunomodulatory and antiangiogenic effects that has been successfully used for the treatment of low and intermediate-1 risk myelodysplastic syndromes (MDSs) with a del(5q) aberration. Because information about the influence of lenalidomide on the microRNA (miRNA) transcriptome is limited, we performed miRNA expression profiling of bone marrow CD34+ cells obtained from MDS patients with the del(5q) abnormality who had been subjected to lenalidomide treatment. To define differences in miRNA expression, we performed paired data analysis to compare the miRNA profiles of patients before and during lenalidomide treatment and those of healthy donors. The analysis showed that miRNAs clustering to the 14q32 region had a higher expression level in patient samples before treatment than in the healthy control samples, and this elevated expression was diminished following lenalidomide administration. Because some of the 14q32 miRNAs play important roles in hematopoiesis, stem cell differentiation, and apoptosis induction, the expression of this cluster may be associated with the pathophysiology of the disease.

MicroRNA-377 suppresses cell proliferation and invasion by inhibiting TIAM1 expression in hepatocellular carcinoma

Increasing evidence has suggested that microRNAs (miRNAs) play an important role in the initiation and progression of hepatocellular carcinoma (HCC). Here, we identified a novel tumor suppressive miRNA, miR-377, and investigated its role in HCC. The expression of miR-377 in HCC tissues and cell lines was detected by real-time reverse-transcription PCR. The effects of miR-377 on HCC cell proliferation and invasion were also investigated. Western blot and luciferase reporter assay were used to identify the direct and functional target of miR-377. The expression of miR-377 was markedly downregulated in human HCC tissues and cell lines. MiR-377 can dramatically inhibit cell growth and invasion in HCC cells. Subsequent investigation revealed that T lymphoma invasion and metastasis 1 (TIAM1) was a direct and functional target of miR-377 in HCC cells. Overexpression of miR-377 impaired TIAM1-induced promotion of proliferation and invasion in HCC cells. Finally, miR-377 is inversely correlated with TIAM1 expression in human HCC tissues. These findings reveal that miR-377 functions as a tumor suppressor and inhibits the proliferation and invasion of HCC cells by targeting TIAM1, which may consequently serve as a therapeutic target for HCC patients.

The downregulation of miR-144 is associated with the growth and invasion of osteosarcoma cells through the regulation of TAGLN expression

Alterations in the expression of microRNAs (miRNAs or miRS) have been implicated in the pathogenesis of the majority of human malignancies, and the dysregulation of microRNA-144 (miR-144) has been associated with several diseases. However, the potential involvement of miR-144 in osteosarcoma, a common malignant bone tumor in children and adolescents with a high risk of relapse and metastasis, has not yet been fully investigated. In the present study, we examined the expression and roles of miRNAs in osteosarcoma as potential diagnostic markers and therapeutic targets, and we focused on miR-144 due to its known involvement in osteogenesis. We demonstrate that miR-144 is downregulated in osteosarcoma cell lines and primary human osteosarcoma tissue samples and that its ectopic expression inhibits osteosarcoma cell proliferation and invasion. We identified TAGLN as a downstream target of miR-144 and demonstrated that its expression is upregulated in osteosarcoma cell lines and tumor tissue and is inversely correlated with miR-144 expression. Our results indicate that miR-144 may regulate osteosarcoma cell proliferation and invasion by downregulating its target gene, TAGLN, suggesting that miR-144 may be a potential therapeutic target for the treatment of osteosarcoma.

Altered expression pattern of miR-29a, miR-29b and the target genes in myeloid leukemia

Objectives

The miR-29 family have been demonstrated acting as vital tumor suppressor in multiple cancers as well as regulators in the adaptive immune system. Little is known about their role in leukemogenesis. The purpose of this study is to analyze the expression pattern of miR-29a/29b and its target genes Mcl-1 (myeloid cell leukemia sequence 1) and B-cell lymphoma 2 (Bcl-2) in myeloid leukemia.

Methods

Quantitative real-time PCR was used for detecting genes expression level in peripheral blood mononuclear cells (PBMCs) from 10 cases with newly diagnosed, untreated acute myeloid leukemia (AML) and 14 cases with newly diagnosed, untreated chronic myeloid leukemia (CML) in chronic phase, and 14 healthy individual (HI) served as controls. Correlation between the relative expression levels of different genes have been analyzed.

Results

Significant lower expression of miR-29a/29b and higher expression level of two potential target genes Bcl-2 and Mcl-1 were found in PBMCs from AML and CML patients compared with HI group. In addtion, miR-29a expression in AML was significantly lower than that in CML. Moreover, negative correlation between miR-29a/29b and its target genes have been found. While, positive correlation between relative expression level of miR-29a and miR-29b or Bcl-2 and Mcl-1 were presented in the total 38 research objects.

Conclusion

Down-regulated miR-29a and miR-29b, and accompanying up-regulated Bcl-2 and Mcl-1 are the common feature in myeloid leukemias. These data further support the role for miR-29a/29b dysregulation in myeloid leukemogenesis and the therapeutic promise of regulating miR-29a/29b expression for myeloid leukemia in the future.

MicroRNA-1 functions as a potential tumor suppressor in osteosarcoma by targeting Med1 and Med31

MicroRNA-1 (miR-1) has been shown to function as a critical gene regulator in multiple types of cancers. However, the role of miR-1 in osteosarcoma has not been totally clarified. In the present study, we investigated the effects of miR-1 on osteosarcoma and the underlying mechanism. We found that miR-1 was downregulated in osteosarcoma tissues and osteosarcoma cell lines. Restoration of miR-1 significantly suppressed osteosarcoma cell proliferation by inhibiting cell cycle progression. Mediator complex subunit 1 (Med1) and 31 (Med31) were validated as targets of miR-1 in osteosarcoma by luciferase reporter assay. Downregulation of Med1 and Med31 suppressed the proliferation of osteosarcoma cells, and overexpression of Med1 and Med31 abrogated the effects of miR-1 on cell proliferation. Furthermore, both miR-1 and knockdown of Med1 or Med31 reduced the expression of met proto-oncogene (MET) and blocked the downstream signaling of MET responding to hepatocyte growth factor (HGF). Taken together, the findings of this study suggest that Med1 and Med31 serve as potential gene therapeutic targets in osteosarcoma and miR-1 may prove to be a promising agent.

microRNA‑25 promotes osteosarcoma cell proliferation by targeting the cell‑cycle inhibitor p27

An increasing body of evidence indicates that microRNAs (miRNAs), a class of small non‑coding RNAs, are often aberrantly expressed in human osteosarcoma. This study aimed to investigate the effects of miR‑25 and to identify its potential target genes in osteosarcoma (OS) cells. First, the expression of miR‑25 was detected by reverse transcription‑quantitative polymerase chain reaction (RT-qPCR), which revealed a significant upregulation of miR‑25 in osteosarcoma tissues compared to the adjacent healthy tissues. To investigate the role of miR‑25 in osteosarcoma cell proliferation, the miR‑25 precursor was next transfected into Saos‑2 and U2OS cells. Overexpression of miR‑25 promoted cell proliferation in vitro and tumor growth in a xenograft mouse model. In addition, our results revealed that the protein expression of p27, a cell‑cycle inhibitor, is negatively regulated by miR‑25. Restoring the p27 level in miR‑25‑overexpressing cells reversed the enhancing effect of miR‑25 on cell proliferation. Therefore, miR‑25 may act as an onco‑miRNA in osteosarcoma, which provides new perspectives in cancer treatment strategies based on molecular targeting.

From wavy hair to naked proteins: the role of transforming growth factor alpha in health and disease

Since its discovery in 1978 and cloning in 1984, transforming growth factor-alpha (TGF-α, TGFA) has been one of the most extensively studied EGF receptor (EGFR) ligands. In this review, we provide a historical perspective on TGFA-related studies, highlighting what we consider important advances related to its function in normal and disease states.

miRNA-218 inhibits osteosarcoma cell migration and invasion by down-regulating of TIAM1, MMP2 and MMP9

Deregulated miRNAs participate in osteosarcoma genesis. In this study, the expression of miRNA-218 in human osteosarcomas, adjacent normal tissues and Saos-2 human osteosarcoma cells was first assessed. Then the precise role of miRNA-218 in osteosarcoma cells was investigated. Upon transfection with a miR-218 expression vector, the proliferation of Saos-2 human osteosarcoma cells determined using the ATPlite assay was significantly suppressed, whilw migration of Saos-2 cells detected by wound healing and invasion determined using transwells were dramatically inhibited. Potential target genes of miR-218 were predicted and T-cell lymphoma invasion and metastasis 1 (TIAM1) and matrix metalloproteinase 2 (MMP2) and 9 (MMP9) were identified. This was confirmed by western blotting, which showed that miR-218 expression inhibited TIAM1, MMP2 and MMP9 protein expression. Collectively, these data suggest that miR-218 acts as a tumor suppressor in osteosarcomas by down-regulating TIAM1, MMP2 and MMP9 expression.

MicroRNAs in osteosarcomagenesis

The etiology of osteosarcoma (OS) remains enigmatic. Particular clinical and molecular patterns, observed with high frequency in OS, suggest that it results from some yet-to-be-discovered central driver. How else can biology generate such an aggressive, metastatic, genetically and chromosomally unstable malignancy with virtually no apparent precursor neoplasms that are partway along a disease path toward OS? With this conundrum as a backdrop, the discovery of every new native molecule with power to impact a cell's biology is usually quickly followed by a search to see if this type of molecule contains the key to unlock OS biology.