Downregulation of miR-22 acts as an unfavorable prognostic biomarker in osteosarcoma

MicroRNA signatures in osteosarcoma: diagnostic insights and therapeutic prospects

Osteosarcoma (OSa) is the most prevalent primary malignant bone tumor in children and adolescents, characterized by complex genetic and epigenetic alterations. Traditional treatments face significant challenges due to high rates of drug resistance and lack of targeted therapies. Recent advances in microRNA (miRNA) research have opened new avenues for understanding and treating osteosarcoma. This review explores the many critical functions of miRNAs in osteosarcoma, particularly their potential for clinical use. The review highlights two key areas where miRNAs could be beneficial. Firstly, miRNAs can act as biomarkers for diagnosing osteosarcoma and predicting patient prognosis. Secondly, specific miRNAs can regulate cellular processes like proliferation, cell death, migration, and even resistance to chemotherapy drugs in osteosarcoma. This ability to target multiple pathways within cancer cells makes miRNA-based therapies highly promising. Additionally, though the interaction between miRNAs and circular RNAs (circRNAs) falls outside the scope of the paper, it has also been discussed briefly. While miRNA-based therapies offer exciting possibilities for targeting multiple pathways in osteosarcoma, challenges remain. Efficient delivery, potential off-target effects, tumor complexity, and rigorous testing are hurdles to overcome before these therapies can reach patients. Despite these challenges, continued research and collaboration among scientists, clinicians, and regulatory bodies hold the promise of overcoming them. This collaborative effort can pave the way for the development of safe and effective miRNA-based treatments for osteosarcoma.

Transcriptional regulation and therapeutic potential of cyclin-dependent kinase 9 (CDK9) in sarcoma

Sarcomas include various subtypes comprising two significant groups - soft tissue and bone sarcomas. Although the survival rate for some sarcoma subtypes has improved over time, the current methods of treatment remain efficaciously limited, as recurrent, and metastatic diseases remain a major obstacle. There is a need for better options and therapeutic strategies in treating sarcoma. Cyclin dependent kinase 9 (CDK9) is a transcriptional kinase and has emerged as a promising target for treating various cancers. The aberrant expression and activation of CDK9 have been observed in several sarcoma subtypes, including rhabdomyosarcoma, synovial sarcoma, osteosarcoma, Ewing sarcoma, and chordoma. Enhanced CDK9 expression has also been correlated with poorer prognosis in sarcoma patients. As a master regulator of transcription, CDK9 promotes transcription elongation by phosphorylation and releasing RNA polymerase II (RNAPII) from its promoter proximal pause. Release of RNAPII from this pause induces transcription of critical genes in the tumor cell. Overexpression and activation of CDK9 have been observed to lead to the expression of oncogenes, including MYC and MCL-1, that aid sarcoma development and progression. Inhibition of CDK9 in sarcoma has been proven to reduce these oncogenes' expression and decrease proliferation and growth in different sarcoma cells. Currently, there are several CDK9 inhibitors in preclinical and clinical investigations. This review aims to highlight the recent discovery and results on the transcriptional role and therapeutic potential of CDK9 in sarcoma.

Autophagy Modulation as a Potential Therapeutic Strategy in Osteosarcoma: Current Insights and Future Perspectives

Autophagy, the process that enables the recycling and degradation of cellular components, is essential for homeostasis, which occurs in response to various types of stress. Autophagy plays an important role in the genesis and evolution of osteosarcoma (OS). The conventional treatment of OS has limitations and is not always effective at controlling the disease. Therefore, numerous researchers have analyzed how controlling autophagy could be used as a treatment or strategy to reverse resistance to therapy in OS. They highlight how the inhibition of autophagy improves the efficacy of chemotherapeutic treatments and how the promotion of autophagy could prove positive in OS therapy. The modulation of autophagy can also be directed against OS stem cells, improving treatment efficacy and preventing cancer recurrence. Despite promising findings, future studies are needed to elucidate the molecular mechanisms of autophagy and its relationship to OS, as well as the mechanisms underlying the functioning of autophagic modulators. Careful evaluation is required as autophagy modulation may have adverse effects on normal cells, and the optimization of autophagic modulators for use as drugs in OS is imperative.

The spectrum and significance of secondary (co-occurring) genetic alterations in sarcomas: the hallmarks of sarcomagenesis

Bone and soft tissue tumors are generally classified into complex karyotype sarcomas versus those with recurrent genetic alterations, often in the form of gene fusions. In this review, we provide an overview of important co-occurring genomic alterations, organized by biological mechanisms and covering a spectrum of genomic alteration types: mutations (single-nucleotide variations or indels) in oncogenes or tumor suppressor genes, copy number alterations, transcriptomic signatures, genomic complexity indices (e.g. CINSARC), and complex genomic structural variants. We discuss the biological and prognostic roles of these so-called secondary or co-occurring alterations, arguing that recognition and detection of these alterations may be significant for our understanding and management of mesenchymal tumors. On a related note, we also discuss major recurrent alterations in so-called complex karyotype sarcomas. These secondary alterations are essential to sarcomagenesis via a variety of mechanisms, such as inactivation of tumor suppressors, activation of proliferative signal transduction, telomere maintenance, and aberrant regulation of epigenomic/chromatin remodeling players. The use of comprehensive genomic profiling, including targeted next-generation sequencing panels or whole-exome sequencing, may be incorporated into clinical workflows to offer more comprehensive, potentially clinically actionable information. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

miR-22-3p and miR-30e-5p Are Associated with Prognosis in Cervical Squamous Cell Carcinoma

Alteration in expression of miRNAs can cause various malignant changes and the metastatic process. Our aim was to identify the miRNAs involved in cervical squamous cell carcinoma (SqCC) and metastasis, and to test their utility as indicators of metastasis and survival. Using microarray technology, we performed miRNA expression profiling on primary cervical SqCC tissue (n = 6) compared with normal control (NC) tissue and compared SqCC that had (SqC-M; n = 3) and had not (SqC-NM; n = 3) metastasized. Four miRNAs were selected for validation by qRT-PCR on 29 SqC-NM and 27 SqC-M samples, and nine metastatic lesions (ML-SqC), from a total of 56 patients. Correlation of miRNA expression and clinicopathological parameters was analyzed to evaluate the clinical impact of candidate miRNAs. We found 40 miRNAs differentially altered in cervical SqCC tissue: 21 miRNAs were upregulated and 19 were downregulated (≥2-fold, p < 0.05). Eight were differentially altered in SqC-M compared with SqC-NM samples: four were upregulated (miR-494, miR-92a-3p, miR-205-5p, and miR-221-3p), and four were downregulated (miR-574-3p, miR-4769-3p, miR-1281, and miR-1825) (≥1.5-fold, p < 0.05). MiR-22-3p might be a metastamiR, which was gradually further downregulated in SqC-NM > SqC-M > ML-SqC. Downregulation of miR-30e-5p significantly correlated with high stage, lymph node metastasis, and low survival rate, suggesting an independent poor prognostic factor.

Identification of plasma microRNA-22 as a marker for the diagnosis, prognosis, and chemosensitivity prediction of osteosarcoma

Objective

MicroRNA (miR)-22 plays crucial roles in malignant tumors and is involved in regulation of chemosensitivity. Additionally, altered expression of circulating miR-22 has been reported in various cancers. This study was designed to investigate plasma miR-22 expression in patients with osteosarcoma (OS) and determine its diagnostic, prognostic, and chemosensitivity prediction value.

Methods

Plasma miR-22 levels in 120 patients with OS and 120 healthy controls were detected by real-time quantitative reverse transcription PCR. Associations of plasma miR-22 expression with the patients’ clinicopathological features and prognosis were then assessed.

Results

Plasma miR-22 levels in patients with OS were significantly lower than those in healthy controls. Low plasma miR-22 levels were correlated with large tumor size, advanced clinical stages, positive distant metastasis, and poor tumor response to preoperative chemotherapy. Plasma miR-22 could discriminate OS patients from controls and distinguish patients with a good response to therapy from those with a poor response to therapy. Multivariate analysis revealed that low plasma miR-22 expression was a significant independent predictor of unfavorable prognosis.

Conclusions

Altered plasma levels of miR-22 might serve as a novel, noninvasive biomarker for OS diagnosis, prognosis, and chemosensitivity prediction.

Circulating extracellular vesicle-encapsulated microRNA as screening biomarkers for intraductal papillary mucinous neoplasm

Since intraductal papillary mucinous neoplasms (IPMNs) occasionally contain pancreatic malignancies, it is vital to develop a screening program that can detect IPMNs in the general population and that can identify IPMNs with high malignant potential. The present study investigated whether microRNAs (miRNAs/miRs) in the blood may be diagnostic markers for IPMN screening. Initially, extracellular vesicle-encapsulated miRNAs (EV-miRNAs) in the serum with altered expression between IPMN, IPMN-derived carcinoma (IPMC) and control samples, were identified using microarray analysis. To validate the microarray results, the expression levels of selected EV-miRNAs were detected. Briefly, serum EV-miRNAs were extracted from 38 patients with IPMN (11 patients with IPMC and 27 patients with benign IPMN) and 21 non-tumor controls. The results of the microarray analysis revealed that the expression levels of EV-miR-22-3p, EV-miR-4539 and EV-miR-6132 were higher in the IPMN and IPMC serum samples compared with those in the control samples. With regards to discriminating IPMNs from controls, only miR-4539 exhibited a significant difference (P=0.004). In the comparison between IPMN and IPMC, carcinogenic antigen 19-9 (CA19-9) and EV-miR-6132 exhibited significant differences (P=0.01 and P=0.007, respectively). Receiver operating characteristic (ROC) curve analysis demonstrated that EV-miR-4539 could discriminate patients with IPMNs from control patients, with an area under the curve (AUC) of 0.72. Additionally, ROC analysis indicated that the markers could discriminate patients with IPMC from benign IPMN, with AUC values of 0.77 for EV-miR-6132 and 0.74 for CA19-9. In conclusion, the present study suggested that EV-miRNAs may be used as diagnostic markers for the detection of IPMNs in the general population as well as for identifying IPMNs with high malignant potential.

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.

miR-331-3p suppresses cell invasion and migration in colorectal carcinoma by directly targeting NRP2

Colorectal carcinoma (CRC) is a common tumor of the digestive system with poor prognosis. Studies have shown that aberrant microRNA (miRNA) expression can affect CRC progression by regulating target genes. In the present study, we investigated the functional roles and potential mechanisms of miR-331-3p in CRC. The expression of miR-331-3p and neuropilin-2 (NRP2) in CRC was detected by RT-qPCR. Then, Transwell assays were conducted to investigate the influence of miR-331-3p on CRC cell invasion and migration abilities. Luciferase reporter assays were performed to determine the target gene of miR-331-3p. It was found that miR-331-3p expression was notably declined in CRC and inversely correlated with the NRP2 expression. miR-331-3p upregulation significantly inhibited CRC cell invasion and migration. Additionally, western blot analysis demonstrated that miR-331-3p restoration evidently suppressed CRC cell EMT. Moreover, NRP2 was conformed to be a novel target of miR-331-3p and knockdown of NRP2 partially inversed the effects of the miR-331-3p inhibitor on cell invasion and migration. These results suggested that miR-331-3p exerted tumor suppressive roles in CRC by targeting NRP2 and miR-331-3p/NRP2 may serve as a potential therapy for CRC.

Survival advantage and clinicopathological significance of microRNA-22 in cancers: a meta-analysis

An increasing number of studies revealed that microRNA-22 as a biomarker may play a significant role in the cancer patients' prognosis, but the accurate prognosis value of microRNA-22 remains somewhat controversial. Thus, we comprehensively searched the database and performed this study to explicate the accurate value of microRNA-22 in the cancer patients' prognosis. This meta-analysis revealed that elevated expression of microRNA-22 correlated with good overall survival (OS) and disease-free survival (DFS)/progression-free survival (PFS)/recurrence-free survival (RFS) in cancers, while no significant association was found in metastasis-free survival (MFS)/distant metastasis-free survival (DMFS). Through the subgroup analysis for OS and DFS/PFS/RFS, we found that elevated expression of miR-22 significantly correlated with good prognosis in most subgroups, while it predicted a worse prognosis in nasopharyngeal carcinoma subgroup. And besides that, elevated expression of miR-22 was negatively correlated with TNM stage, lymph node metastasis, distant metastasis and recurrence, while no significant association was found between microRNA-22 expression and T stage, tumor differentiation, and lymphatic invasion. Our meta-analysis demonstrated that elevated expression of microRNA-22 predicted a good OS and DFS/PFS/RFS in cancer patients; meanwhile, its high expression also means earlier TNM stage, and lower likelihoods of lymph node metastasis, of distant metastasis and of recurrence. If we regularly monitor miR-22 expression in cancer patients, it might be useful for us to predict cancer prognosis in future clinical applications.

Identification and validation of microRNAs and their targets expressed in osteosarcoma

Osteosarcoma (OS) is the most common type of bone cancer in children and adolescents, and has a poor prognosis. Previous studies have demonstrated that a number of microRNAs (miRNAs) were deregulated in OS, and that the expression of certain miRNAs was correlated with the stage of OS. Therefore, miRNAs may serve a role as a diagnostic and prognostic biomarker of OS. miRNA and mRNA integrated analysis of public expression profiles in the Gene Expression Omnibus database for OS was performed, and the regulated targets of miRNA in OS were predicted. Next, the regulatory network of miRNAs/genes was constructed and verified by reverse transcription-quantitative polymerase chain reaction in tissues and MG-63 cell lines. Two miRNA expression profiling studies and four eligible mRNA expression profiling studies were selected. Ten upregulated miRNAs, 5 downregulated miRNAs and 5 DGEs were identified in OS compared with normal tissues. hsa-miR-346 was inversely correlated with the target gene c-FLIP, which was consistent with the results of integrated analysis. In vitro, pre-miRNA-346 can downregulate the protein expression of c-FLIP, while not changing the mRNA level of c-FLIP. In the regulatory network, hsa-miR-346 and its target gene, c-FLIP, can be used as biomarkers for an earlier diagnosis of OS.

Circulating microRNA-22-3p Predicts the Malignant Progression of Precancerous Gastric Lesions from Intestinal Metaplasia to Early Adenocarcinoma

BACKGROUND

Gastric cancer has a poor outcome and identifying useful biomarkers from peripheral blood or tissue could allow its early detection, or potentially precancerous changes, thus improving the curative rates. MicroRNAs (miRNAs) have been shown to offer great potential in cancer diagnosis and prediction.

AIM

Here, we investigated the role of plasma miRNAs in the natural course of gastric cancer, from intestinal metaplasia to early cancer. The findings were used to understand whether patients at a high risk of malignancy could be given appropriate interventions in the early disease process, such as using endoscopic submucosal dissection to treat gastric dysplasia or early gastric cancer.

METHODS

Participants were divided into healthy control, intestinal metaplasia (IM), and dysplasia/early cancer (pT1a/b) groups. Microarray was used to select potential markers in tissue.

RESULTS

Quantitative real-time polymerase chain reaction data showed circulating miRNA-22-3p had significantly different expression in patients with precancerous lesions or gastric adenocarcinoma. The areas under the curve of incomplete IM versus healthy control, low-grade/high-grade dysplasia, early gastric cancer, and GED were 0.8080, 0.8040, 0.8494, and 0.8095, respectively (all P values < 0.05).

CONCLUSIONS

Circulating miRNA-22-3p could be a potential biomarker for gastric precancerous dysplasia and early cancer detection.

MicroRNA-874 inhibits cell proliferation and invasion by targeting cyclin-dependent kinase 9 in osteosarcoma

MicroRNAs (miRNAs) perform important roles in the development and progression of human malignancy. miR-874, as a tumor suppressor, is decreased in malignant tumors, including osteosarcoma. However, the potential mechanism of miR-874 in osteosarcoma remains largely unknown. In the present study, a dual-luciferase reporter system supported cyclin-dependent kinase 9 (CDK9) as a direct target gene of miR-874. miR-874 mimics evidently repressed CDK9 expression in osteosarcoma. Furthermore, osteosarcoma tissues and cell lines exhibited increased expression of CDK9, and CDK9 expression levels were inversely correlated (R=−0.725) with that of miR-874 in osteosarcoma tissues. Finally, CDK9 overexpression reversed the potential effect of miR-874 on the proliferation and invasion of osteosarcoma cells. Overall, the results revealed that miR-874, as a tumor suppressor, is involved in osteosarcoma progression and metastasis by targeting CDK9, indicating that the miR-874/CDK9 pathway may serve as a potential therapeutic target for the treatment of osteosarcoma.

Prognostic value of microRNAs in osteosarcoma: A meta-analysis

BACKGROUND

Osteosarcoma is the most common primary bone malignancy. We meta-analyzed the prognostic value of altered miRNAs in patients with osteosarcoma.

METHODS

Sources from MEDLINE (from inception to August 2016) and EMBASE (from inception to August 2016) were searched. Studies of osteosarcoma with results of miRNA and studies that reported survival data were included and two authors performed the data extraction independently. Any discrepancies were resolved by a consensus. The outcome was overall survival and event-free survival assessed using hazard ratios (HRs).

RESULTS

After reviewing the full text of 65 articles, 25 studies including 2,278 patients were eligible in this study. The pooled HR for deaths was 1.40 (95% confidence interval [CI] 1.01-1.94, p=0.04) with random-effects model (χ2=113.08, p<0.00001, I2=79%) for patients of osteosarcoma with lower expression of miRNA. However, the pooled HR for events was not significant (HR 0.97, 0.63-1.48, p=0.87, χ2=72.65, p<0.00001, I2=79%). In pathway analysis of miRNAs, miRNA449a, 199-5p, 542-5p have common target genes.

CONCLUSIONS

Expression level of miRNA in patients of osteosarcoma is important as a prognostic factor.

miR-22-Notch Signaling Pathway Is Involved in the Regulation of the Apoptosis and Autophagy in Human Ovarian Cancer Cells

microRNA-22 (miR-22) is a brain-enriched regulatory gene which has been reported to be involved in the development of cancers. The Notch signaling pathway exerts important functions in cell growth. This study is designed to investigate the mechanisms of miR-22-Notch signaling pathway in apoptosis and autophagy of human ovarian cancer cells. After over-expressing miR-22 in human ovarian cancer cell lines OVCAR-3 and SKOV3, cell viability is determined by 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) method, cell apoptosis is observed by Flow cytometry (FCM), mRNA expression of miR-22 is measured by RNA preparation and RT-PCR, protein expression of Notch1, Hes1, Beclin1 and LC3B-II is analyzed by Western blot. It is suggested that miR-22 expression is heavily decreased in human ovarian cancer cell lines OVCAR-3 and SKOV3. Over-expression of miR-22 potently suppresses cell viability and authophagy while promotes the percentage of apoptotic cancer cells. In addition, the decreased expression level of Notch1 and its targeted gene is detected in miR-22-over-expressed cells. Moreover, followed by the block of the Notch signaling pathway using Notch1 small interference RNA (siRNA), the effects of miR-22 on the apoptosis and autophagy of human ovarian cancer cell lines OVCAR-3 and SKOV3 are obviously blocked. Together, miR-22 inhibits apoptosis and promotes autophagy of human ovarian cancer cells through the suppression of the Notch signaling pathway, indicating a potential use of miR-22 in the ovarian cancer treatment.

Blood transcriptional and microRNA responses to short-term exposure to disinfection by-products in a swimming pool

BACKGROUND

Swimming in a chlorinated pool results in high exposure levels to disinfection by-products (DBPs), which have been associated with an increased risk of bladder cancer.

OBJECTIVES

By studying molecular responses at the blood transcriptome level we examined the biological processes associated with exposure to these compounds.

METHODS

Whole-genome gene expression and microRNA analysis was performed on blood samples collected from 43 volunteers before and 2h after 40min swimming in an indoor chlorinated pool (PISCINAII study). Exposure to THMs was measured in exhaled breath. Heart rate and kcal expenditure were measured as proxies for physical activity. Associations between exposure levels and gene expression were assessed using multivariate normal models (MVN), correcting for age, body mass index and sex. A Bonferroni threshold at 5% was applied.

RESULTS

MVN-models for the individual exposures identified 1778 genes and 23 microRNAs that were significantly associated with exposure to at least one DBP. Due to co-linearity it was not possible to statistically disentangle responses to DBP exposure from those related to physical activity. However, after eliminating previously reported transcripts associated with physical activity a large number of hits remained associated with DBP exposure. Among those, 9 were linked with bladder and 31 with colon cancer. Concordant microRNA/mRNA expressions were identified in association with DBP exposure for hsa-mir-22-3p and hsa-miR-146a-5p and their targets RCOR1 and TLR4, both related to colon cancer in association with DBP exposure.

CONCLUSIONS

Short-term exposure to low levels of DBPs shows genomics responses that may be indicative of increased cancer risk.

Comprehensive and Integrated Genomic Characterization of Adult Soft Tissue Sarcomas

Sarcomas are a broad family of mesenchymal malignancies exhibiting remarkable histologic diversity. We describe the multi-platform molecular landscape of 206 adult soft tissue sarcomas representing 6 major types. Along with novel insights into the biology of individual sarcoma types, we report three overarching findings: (1) unlike most epithelial malignancies, these sarcomas (excepting synovial sarcoma) are characterized predominantly by copy-number changes, with low mutational loads and only a few genes (TP53, ATRX, RB1) highly recurrently mutated across sarcoma types; (2) within sarcoma types, genomic and regulomic diversity of driver pathways defines molecular subtypes associated with patient outcome; and (3) the immune microenvironment, inferred from DNA methylation and mRNA profiles, associates with outcome and may inform clinical trials of immune checkpoint inhibitors. Overall, this large-scale analysis reveals previously unappreciated sarcoma-type-specific changes in copy number, methylation, RNA, and protein, providing insights into refining sarcoma therapy and relationships to other cancer types.

Comparative Analysis of MicroRNA Expression among Benign and Malignant Tongue Tissue and Plasma of Patients with Tongue Cancer

Background

Identification of a microRNA (miRNA) pattern to be used as a biomarker for HNSCC is challenging given the heterogeneity of the disease and different methodologies used. To better define the field, we performed a prospective analysis of blood, tumor, and paired benign tissues in tongue squamous cell carcinoma (SCC) patients.

Methods

Plasma samples were collected prior to surgery, and paired tumor and benign tissue blocks were collected from tongue cancer resections. Circulating free and exosomal miRNA, and paired tumor and benign tissues miRNA were analyzed. TaqMan-based miRNA arrays were used to quantitate the expression of 747 human miRNAs. The comparative Ct method assessed the miRNA profile results, and Student’s t-test determined statistical significance between tumor and benign samples.

Results

Sixteen of 359 miRNAs detected were differentially expressed between paired tumor and benign tissue. Nine were upregulated, and seven downregulated in tumor tissue. All nine upregulated and six of seven downregulated tumor miRNAs were expressed in circulating exosomes. In contrast, eight of nine upregulated and four of seven downregulated tumor miRNAs were circulating free in the plasma.

Conclusion

An aberrantly expressed pattern of miRNA was identified in both tumor and plasma of patients with tongue SCC, suggesting this may be a biomarker for SCC of the oral tongue. Circulating exosomes appear to be a more reliable method for evaluation of circulating tumor-miRNA expression. Further studies with a larger cohort of patients and serial blood samples are needed to validate our findings.

MicroRNA-613 inhibits the progression of gastric cancer by targeting CDK9

MicroRNAs (miRNAs) play an important role in the development and progression of human malignancy. miR-613, as a tumour suppressor, was reported to decrease in several tumours. However, the expression levels and role of miR-613 in gastric cancer remain unknown. In this study, we found that miR-613 was evidently downregulated in gastric cancer tissue and cell. The functional analysis showed that miR-613 suppressed cell proliferation and migration in gastric cancer. Next, the dual-luciferase reporter system supported CDK9 as a direct target gene of miR-613. miR-613 mimics evidently repressed CDK9 expression in gastric cancer cells. Furthermore, we found that CDK9 in upregulated in gastric cancer and the CDK9 expression levels were inversely correlated with that of miR-613 in gastric cancer tissues. Overall, the results revealed that miR-613, as a tumour suppressor, involves in gastric cancer progression and metastasis by targeting CDK9, implying a novel potential therapeutic target for the treatment of gastric cancer.

MicroRNAs with prognostic significance in osteosarcoma: a systemic review and meta-analysis

Introduction

This study aimed to elucidate the prognostic value of microRNAs (miRNAs) in patients with osteosarcoma.

Materials and Methods

Studies were recruited by searching PubMed, Embase, the Cochrane Library, China National Knowledge Infrastructure, and Wanfang data-bases (final search update conducted January 2017). Eligible studies were identified and the quality was assessed using multiple search strategies.

Results

A total of 55 articles that investigated the correlation between miRNA expression and either patient survival or disease recurrence in osteosarcoma was initially identified. Among these, 30 studies were included in the meta-analysis. The results of our meta-analysis revealed that elevated levels of miR-21, miR-214, miR-29, miR-9 and miR-148a were associated with poor prognosis in osteosarcoma. Additionally, downregulated miR-382, miR26a, miR-126, miR-195 and miR-124 expression indicated poor prognosis in osteosarcoma.

Conclusions

miRNAs may act as independent prognostic factors in patients with osteosarcoma and are useful in stratifying risk.