MiR-378 promotes the cell proliferation of osteosarcoma through down-regulating the expression of Kruppel-like factor 9

Krüppel-like factors family in health and disease

Krüppel-like factors (KLFs) are a family of basic transcription factors with three conserved Cys2/His2 zinc finger domains located in their C-terminal regions. It is acknowledged that KLFs exert complicated effects on cell proliferation, differentiation, survival, and responses to stimuli. Dysregulation of KLFs is associated with a range of diseases including cardiovascular disorders, metabolic diseases, autoimmune conditions, cancer, and neurodegenerative diseases. Their multidimensional roles in modulating critical pathways underscore the significance in both physiological and pathological contexts. Recent research also emphasizes their crucial involvement and complex interplay in the skeletal system. Despite the substantial progress in understanding KLFs and their roles in various cellular processes, several research gaps remain. Here, we elucidated the multifaceted capabilities of KLFs on body health and diseases via various compliable signaling pathways. The associations between KLFs and cellular energy metabolism and epigenetic modification during bone reconstruction have also been summarized. This review helps us better understand the coupling effects and their pivotal functions in multiple systems and detailed mechanisms of bone remodeling and develop potential therapeutic strategies for the clinical treatment of pathological diseases by targeting the KLF family.

The Landscape of microRNAs in Bone Tumor: A Comprehensive Review in Recent Studies

Cancer, the second greatest cause of mortality worldwide, frequently causes bone metastases in patients with advanced-stage carcinomas such as prostate, breast, and lung cancer. The existence of these metastases contributes to the occurrence of skeletal-related events (SREs), which are defined by excessive pain, pathological fractures, hypercalcemia, and spinal cord compression. These injurious incidents leave uncomfortably in each of the cancer patient's life quality. Primary bone cancers, including osteosarcoma (OS), chondrosarcoma (CS), and Ewing's sarcoma (ES), have unclear origins. MicroRNA (miRNA) expression patterns have been changed in primary bone cancers such as OS, CS, and ES, indicating a role in tumor development, invasion, metastasis, and treatment response. These miRNAs are persistent in circulation and exhibit distinct patterns in many forms of bone tumors, making them potential biomarkers for early detection and treatment of such diseases. Given their crucial regulatory functions in various biological processes and conditions, including cancer, this study aims to look at miRNAs' activities and possible contributions to bone malignancies, focusing on OS, CS, and ES. In conclusion, miRNAs are valuable tools for diagnosing, monitoring, and predicting OS, CS, and ES outcomes. Further research is required to fully comprehend the intricate involvement of miRNAs in these bone cancers and to develop effective miRNA-based treatments.

Krüppel-like Factor-9 and Krüppel-like Factor-13: Highly Related, Multi-Functional, Transcriptional Repressors and Activators of Oncogenesis

Specificity Proteins/Krüppel-like Factors (SP/KLF family) are a conserved family of transcriptional regulators. These proteins share three highly conserved, contiguous zinc fingers in their carboxy-terminus, requisite for binding to cis elements in DNA. Each SP/KLF protein has unique primary sequence within its amino-terminal and carboxy-terminal regions, and it is these regions which interact with co-activators, co-repressors, and chromatin-modifying proteins to support the transcriptional activation and repression of target genes. Krüppel-like Factor 9 (KLF9) and Krüppel-like Factor 13 (KLF13) are two of the smallest members of the SP/KLF family, are paralogous, emerged early in metazoan evolution, and are highly conserved. Paradoxically, while most similar in primary sequence, KLF9 and KLF13 display many distinct roles in target cells. In this article, we summarize the work that has identified the roles of KLF9 (and to a lesser degree KLF13) in tumor suppression or promotion via unique effects on differentiation, pro- and anti-inflammatory pathways, oxidative stress, and tumor immune cell infiltration. We also highlight the great diversity of miRNAs, lncRNAs, and circular RNAs which provide mechanisms for the ubiquitous tumor-specific suppression of KLF9 mRNA and protein. Elucidation of KLF9 and KLF13 in cancer biology is likely to provide new inroads to the understanding of oncogenesis and its prevention and treatments.

Alteration in Levels of Specific miRNAs and Their Potential Protein Targets between Human Pancreatic Cancer Samples, Adjacent Normal Tissue, and Xenografts Derived from These Tumors

Herein, we describe the global comparison of miRNAs in human pancreatic cancer tumors, adjacent normal tissue, and matched patient-derived xenograft models using microarray screening. RNA was extracted from seven tumor, five adjacent normal, and eight FI PDX tumor samples and analyzed by Affymetrix GeneChip miRNA 4.0 array. A transcriptome analysis console (TAC) was used to generate comparative lists of up- and downregulated miRNAs for the comparisons, tumor vs. normal and F1 PDX vs. tumor. Particular attention was paid to miRNAs that were changed in the same direction in both comparisons. We identified the involvement in pancreatic tumor tissue of several miRNAs, including miR4534, miR3154, and miR4742, not previously highlighted as being involved in this type of cancer. Investigation in the parallel mRNA and protein lists from the same samples allowed the elimination of proteins where altered expression correlated with corresponding mRNA levels and was thus less likely to be miRNA regulated. Using the remaining differential expression protein lists for proteins predicted to be targeted for differentially expressed miRNA on our list, we were able to tentatively ascribe specific protein changes to individual miRNA. Particularly interesting target proteins for miRs 615-3p, 2467-3p, 4742-5p, 509-5p, and 605-3p were identified. Prominent among the protein targets are enzymes involved in aldehyde metabolism and membrane transport and trafficking. These results may help to uncover vulnerabilities that could enable novel approaches to treating pancreatic cancer.

Depicting the Implication of miR-378a in Cancers

MicroRNA-378a (miR-378a), including miR-378a-3p and miR-378a-5p, are encoded in PPARGC1B gene. miR-378a is essential for tumorigenesis and is an independent prognostic biomarker for various malignant tumors. Aberrant expression of miR-378a affects several physiological and pathological processes, including proliferation, apoptosis, tumorigenesis, cancer invasion, metastasis, and therapeutic resistance. Interestingly, miR-378a has a dual functional role in either promoting or inhibiting tumorigenesis, independent of the cancer type. In this review, we comprehensively summarized the role and regulatory mechanisms of miR-378a in cancer development, hoping to provide a direction for its potential use in cancer therapy.

Circular RNA_0078767 upregulates Kruppel-like factor 9 expression by targeting microRNA-889, thereby inhibiting the progression of osteosarcoma

Among kids and juveniles, osteosarcoma (OS) is a common bone malignancy. Circular RNAs (circs, circRNAs) play important roles in multiple malignancies including OS, yet circ_0078767ʹs biological functions in OS are far from well elucidated. This study is targeted at understanding circ_0078767ʹs biological functions in OS and its molecular mechanisms. This study confirmed that circ_0078767 expression was reduced in OS cell lines and tissues. Circ_0078767 overexpression remarkably inhibited OS cell growth, migration, invasion, epithelial-mesenchymal transition (EMT), and promoted apoptosis, whereas circ_0078767 knockdown resulted in the opposite effects. MicroRNA-889 (miR-889) was targeted and regulated by circ_0078767, and miR-889 could negatively modulate Kruppel-like factor 9 (KLF9) expression. Besides, circ_0078767 positively regulated KLF9 expression in OS cells via repressing miR-889. In conclusion, circ_0078767 enhances KLF9 expression by targeting miR-889 to inhibit OS progression.

Overexpression of miR-378 Alleviates Chronic Sciatic Nerve Injury by Targeting EZH2

In numerous studies, microRNAs (miRNAs) have been authenticated to play vital roles in the pathophysiology of neuropathic pain and other neurological diseases. In our study, we focused on evaluating miR-378 and its potential effects in neuropathic pain development, as well as the underlying molecular mechanisms. Primarily, a chronic sciatic nerve injury (CCI) rat model was established. Next, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was employed to measure the expression levels of miR-378 and EZH2 mRNA; the EZH2 protein expression levels were detected by western blot. A luciferase activity assay monitored the interaction of miR-378 and EZH2. Mechanical and thermal hyperalgesia was also performed to quantitate the effects of overexpression of miR-378 or EZH2 on the CCI rats. We found that miR-378 was down-regulated in the CCI rats, and the overexpression of miR-378 produced significant relief in their pain management. EZH2 was the downstream gene of miR-378 and was negatively regulated by miR-378. The up-regulation of EZH2 reduced the inhibitory effects of miR-378 on the development of neuropathic pain in the CCI rats. miR-378 acts as an inhibitor in the progression of neuropathic pain via targeting EZH2; the miR-378/EZH2 axis may be a novel target for the diagnosis and therapy of neuropathic pain in clinical treatment.

Advances in the role of miRNAs in the occurrence and development of osteosarcoma

Osteosarcoma (OS) is the most common primary malignant tumor of the skeletal system in the clinic. It mainly occurs in adolescent patients and the pathogenesis of the disease is very complicated. The distant metastasis may occur in the early stage, and the prognosis is poor. MicroRNAs (miRNAs) are non-coding RNAs of about 18–25 nt in length that are involved in post-transcriptional regulation of genes. miRNAs can regulate target gene expression by promoting the degradation of target mRNAs or inhibiting the translation process, thereby the proliferation of OS cells can be inhibited and the apoptosis can be promoted; in this way, miRNAs can affect the metabolism of OS cells and can also participate in the occurrence, invasion, metastasis, and recurrence of OS. Some miRNAs have already been found to be closely related to the prognosis of patients with OS. Unlike other reviews, this review summarizes the miRNA molecules closely related to the development, diagnosis, prognosis, and treatment of OS in recent years. The expression and influence of miRNA molecule on OS were discussed in detail, and the related research progress was summarized to provide a new research direction for early diagnosis and treatment of OS.

MicroRNA-652 promotes cell proliferation and osteosarcoma invasion by directly targeting KLF9

Previous studies have demonstrated that various microRNAs (miRNAs or miRs) are abnormally expressed in osteosarcoma (OS) and serve roles in its malignant development. An in-depth understanding of the specific roles of dysregulated miRNAs in OS may be important for cancer research and the identification of novel therapeutic targets. In the current study, reverse transcription-quantitative PCR was performed to determine miR-652 expression in OS tissues and cell lines. Cell Counting Kit-8 and Transwell invasion assays were used for assessing the effect of miR-652 on the proliferation and invasion of OS cells. Herein, miR-652 expression was assessed in OS and the effects and molecular mechanisms of miR-652 in OS cells were examined. The results revealed that miR-652 expression was significantly upregulated in OS tissues and cell lines compared with adjacent normal tissues and a normal human osteoblast cell line. Furthermore, miR-652 downregulation inhibited the proliferation and invasion of OS cells. miR-652 was also demonstrated to directly interact with the 3'-untranslated region of kruppel-like factor 9 (KLF9) and miR-652 negatively regulated KLF9 expression in OS cells. miR-652 and KLF9 mRNA levels were also revealed to be inversely correlated in OS tissues. Treatment with KLF9 small interfering RNA abolished the suppression of OS proliferation and invasion induced by miR-652 downregulation. miR-652 may serve an oncogenic role in OS cells by targeting KLF9 directly. The results also indicated that miR-652 may be an effective novel therapeutic target for the treatment of patients with OS.

Serum exosomal miR-378 upregulation is associated with poor prognosis in non-small-cell lung cancer patients

Background

Deregulated circulating microRNAs (miRNAs) are potential biomarkers for the early detection and prognosis prediction of non–small‐cell lung cancer (NSCLC). The aim of the present study was to investigate the expression pattern of serum exosomal miR‐378 in NSCLC and its correlation with clinical variables.

Methods

Quantitative reverse transcription‐polymerase chain reaction (qRT‐PCR) was performed to detect serum exosomal miR‐378 levels in 103 patients with NSCLC and 60 control subjects.

Results

Our results showed that serum exosomal miR‐378 was significantly overexpressed in NSCLC patients, and serum exosomal miR‐378 upregulation was clearly associated with positive lymph node metastasis and advanced TNM stage. In addition, receiver operating characteristic (ROC) analysis demonstrated that combination of serum exosomal miR‐378 expression and carcinoembryonic antigen (CEA) had a high discriminating power to differentiate NSCLC subjects from controls. Moreover, serum exosomal miR‐378 levels in 73 NSCLC cases were significantly decreased after radiotherapy and could be used as an indicator of radiotherapeutic response in NSCLC. Furthermore, survival analyses revealed that patients with higher serum exosomal miR‐378 expression had poor overall survival. Multivariate analysis showed that serum exosomal miR‐378 expression was independently associated with overall survival.

Conclusions

Collectively, serum exosomal miR‐378 has strong potential as a promising non‐invasive biomarker for screening and monitoring NSCLC.

microRNA-378a-5p iS a novel positive regulator of melanoma progression

Evaluating the expression levels of miR-378a-5p both in a large melanoma patient cohort from The Cancer Genome Atlas database and in melanoma patients from our Institute, we found that miR-378a-5p is upregulated in metastatic melanoma specimens. miR-378a-5p expression was also increased in melanoma cells resistant to target therapy, and decreased in response to drug treatment. We also demonstrated that overexpression of miR-378a-5p enhances in vitro cell invasion and migration, and facilitates the ability of melanoma cells to form de novo vasculogenic structures. While performing downstream targeting studies, we confirmed the ability of miR-378a-5p to modulate the expression of known target genes, such as SUFU, FUS-1, and KLF9. Luciferase-3′UTR experiments also identified STAMBP and HOXD10 as new miR-378a-5p target genes. MMP2 and uPAR, two HOXD10 target genes, were positively regulated by miR-378a-5p. Genetic and pharmacologic approaches inhibiting uPAR expression and activity evidenced that the in vitro tumor-promoting functions of miR-378a-5p, were in part mediated by uPAR. Of note miR-378a-5p was also able to increase VEGF, as well as in vitro and in vivo angiogenesis. Finally, genetic and pharmacologic modulation of Bcl-2 evidenced Bcl-2 ability to regulate miR-378a-5p expression. In conclusion, to the best of our knowledge, this is the first study demonstrating that miR-378a-5p acts as an oncogenic microRNA in melanoma.

Nanomedicine in osteosarcoma therapy: Micelleplexes for delivery of nucleic acids and drugs toward osteosarcoma-targeted therapies

Osteosarcoma(OS) represents the main cancer affecting bone tissue, and one of the most frequent in children. In this review we discuss the major pathological hallmarks of this pathology, its current therapeutics, new active biomolecules, as well as the nanotechnology outbreak applied to the development of innovative strategies for selective OS targeting. Small RNA molecules play a role as key-regulator molecules capable of orchestrate different responses in what concerns cancer initiation, proliferation, migration and invasiveness. Frequently associated with lung metastasis, new strategies are urgent to upgrade the therapeutic outcomes and the life-expectancy prospects. Hence, the prominent rise of micelleplexes as multifaceted and efficient structures for nucleic acid delivery and selective drug targeting is revisited here with special emphasis on ligand-mediated active targeting. Future landmarks toward the development of novel nanostrategies for both OS diagnosis and OS therapy improvements are also discussed.

CircNFIX promotes progression of glioma through regulating miR-378e/RPN2 axis

Background

Circular RNA nuclear factor I X (circNFIX) has been reported to play an important role in glioma progression. However, the mechanism by which circNFIX participates in glioma progression remains poorly understood.

Methods

GERIA online were used to analyze the abnormally expressed genes in glioma tissues. The expression levels of circNFIX, microRNA (miR)-378e and Ribophorin-II (RPN2) were measured by quantitative real-time polymerase chain reaction or western blot. Cell cycle distribution, apoptosis, glycolysis, migration and invasion were determined by flow cytometry, special kit and trans-well assays, respectively. The target association between miR-378e and circNFIX or RPN2 was confirmed by luciferase reporter assay, RNA immunoprecipitation and pull-down. Xenograft model was established to investigate the role of circNFIX in vivo.

Results

The expression of circNFIX was enhanced in glioma tissues and cells compared with matched controls and high expression of circNFIX indicated poor outcomes of patients. Knockdown of circNFIX led to arrest of cell cycle, inhibition of glycolysis, migration and invasion and promotion of apoptosis in glioma cells. circNFIX was a sponge of miR-378e. miR-378e overexpression suppressed cell cycle process, glycolysis, migration and invasion but promoted apoptosis. miR-378e silence abated the suppressive role of circNFIX knockdown in glioma progression. RPN2 as a target of miR-378e was positively regulated via circNFIX by competitively sponging miR-378e. Silencing circNFIX decreased glioma xenograft tumor growth by regulating miR-378e/RPN2 axis.

Conclusion

Knockdown of circNFIX inhibits progression of glioma in vitro and in vivo by increasing miR-378e and decreasing RPN2, providing a novel mechanism for understanding the pathogenesis of glioma.

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-378 regulates epithelial-mesenchymal transition and metastasis of melanoma by inhibiting FOXN3 expression through the Wnt/β-catenin pathway

MicroRNAs (miRNAs) participate in the development and progression of melanoma. However, while dysregulation of microRNA-378 (miR-378) has been seen in various cancer types, its clinical importance and function in melanoma are poorly elucidated. In this work, miR-378 expression in melanoma and in adjacent non-cancerous tissue was evaluated with a quantitative real-time polymerase chain reaction. A series of assays (wound healing, Transwell, and nude mouse subcutaneous tumor model) were used to investigate the implications of abnormal miR-378 regulation on melanoma cell migration and invasion in vitro, and on tumorigenicity in vivo. Prediction and conformation of the miR-378 target gene was undertaken using bioinformatic analysis and luciferase reporter system. Expression of miR-378 was often increased in melanoma, and shown to potentiate its migration, invasion, and tumorigenicity. miR-378 acted, at least partially, through inhibition of the potential target FOXN3 and via Wnt/β-catenin pathway activation. The findings indicate that miR-378 triggers melanoma development and progression. This miRNA could be a novel diagnostic and prognostic biological marker and provide utility for targeted treatment of melanoma.

MicroRNA‑330‑5p inhibits osteosarcoma cell growth and invasion by targeting the proto‑oncogene survivin

Increasing evidence has suggested the crucial role of the dysregulation of microRNAs (miRNAs) in osteosarcoma (OS) progression. MicroRNA (miR)-330-5p has been reported to exert tumor suppressive effects in various types of human cancer. However, the role of miR-330-5p in the development of OS and the underlying mechanism remain to be clarified. In the present study, miR-330-5p expression was found to be significantly decreased in OS tissues and cell lines. In addition, low miR-330-5p expression was highly correlated with the overall survival and clinical stage of OS. Overexpression of miR-330-5p inhibited the viability, migration and invasion, and promoted the apoptosis of OS cells, as well as induced cell cycle arrest at the G₂/M phase. Subsequently, the proto-oncogene survivin was identified as a functional target of miR-330-5p, and this was validated using a luciferase reporter assay. It was also demonstrated that survivin expression was markedly increased in OS tissues, and that it was negatively correlated with the expression of miR-330-5p. Furthermore, overexpression of survivin significantly abrogated the tumor-suppressive effect induced by miR-330-5p on OS cells. In conclusion, these results revealed that the miR-330-5p/survivin axis has a significant tumor-suppressive effect on OS, and may serve as a diagnostic and therapeutic target for the treatment of OS.

Let-7a inhibits osteosarcoma cell growth and lung metastasis by targeting Aurora-B

Purpose

Accumulating studies showed that the expression of microRNAs (miRNAs) was dysregulated in osteosarcoma (OS). In this study, we sought to investigate the effect of let-7a on OS progression and its potential molecular mechanism.

Patients and methods

Quantitative real-time PCR (qRT-PCR) was performed to evaluate the expression level of let-7a and Aurora-B (AURKB) in OS tissues and cells. The OS cells were treated with let-7a mimic, let7a inhibitor, negative mimic and Lv-AURKB combined with let-7a. The ability of cell proliferation, migration and invasion was measured using Cell Counting Kit-8 (CCK-8) and wound-healing and transwell invasion assays. The protein of AURKB, NF-κβp65, MMP2 and MMP9 was measured by Western blot analysis. Xenograft model was performed to investigate the effects of let-7a on tumor growth and metastasis. The lung metastasis was measured by counting the metastatic node using H&E staining.

Results

Let-7a expression was significantly underexpressed in OS cell lines and tissues compared with human osteoblast cell lines, hFOB1.19, and adjacent normal bone tissues. Exogenous let-7a inhibited the viability, migratory and invasive ability of OS cells in vitro. In addition, the overexpression of AURKB in OS cells could partly rescue let-7a-mediated tumor inhibition. Also, the overexpression of let-7a inhibited OS cell growth and lung metastasis in vivo. Furthermore, the results showed that let-7a could decrease the expression of NF-κβp65, MMP2 and MMP9 proteins by targeting AURKB in OS cells.

Conclusion

Let-7a inhibits the malignant phenotype of OS cells by targeting AURKB at least partially. Targeting let-7a and AURKB/NF-κβ may be a novel therapeutic strategy for the treatment of OS.