miR-421 promotes apoptosis and suppresses metastasis of osteosarcoma cells via targeting LTBP2

Expression of E-cadherin and N-cadherin in Epithelial-to-Mesenchymal Transition of Osteosarcoma: A Systematic Review

Osteosarcoma (OS) is a debilitating cancer of the bone that commonly afflicts the young and old. This may be de novo or associated with tumorigenic syndromes. However, many molecular mechanisms are still being uncovered and may offer greater avenues for screening and therapy. Cadherins, including E-cadherin and N-cadherin/vimentin, are involved in epithelial-to-mesenchymal transmission (EMT), which is key for tumor invasion. A study reviewing the relationship between OS and cadherins might elucidate a potential target for therapy and screening. A robust literature review was conducted by searching PubMed with the keywords "osteosarcoma", "cadherin", "e-cadherin" and "n-cadherin". Of a preliminary 266 papers, 25 were included in the final review. Review articles and those without primary data were excluded. Loss of E-cadherin is noted in metastatic cell lines of osteosarcoma. Overexpression of E-cadherin or knockout of N-cadherin/vimentin results in loss of metastatic potential. There are several methods of gene knockout, including CRISPR-Cas9 gene editing, viral vector insertion with micro RNA complementary to long noncoding RNA within gene segments, or proteomic editing. Screening for EMT and genetic treatment of EMT is a possible avenue for the treatment of refractory osteosarcoma. Several studies were conducted ex vivo. Further testing involving in vitro therapy is necessary to validate these methods. Limitations of this study involve a lack of in vivo trials to validate methods.

Integrated co-expression analysis of regulatory elements (miRNA, lncRNA, and TFs) in bovine monocytes induced by Str. uberis

Non-coding RNAs, including long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), together with transcription factors, are critical pre-, co-, and post-transcriptional regulators. In addition to their criteria as ideal biomarkers, they have great potential in disease prognosis, diagnosis, and treatment of complex diseases. Investigation of regulatory mechanisms in the context of bovine mastitis, as most common and economic disease in the dairy industry, to identify elements influencing the expression of candidate genes as key regulators of the mammary immune response is not yet fully understood. Transcriptome profiles (50 RNA-Seq and 50 miRNA-Seq samples) of bovine monocytes induced by Str. uberis were used for co-expression module detection and preservation analysis using the weighted gene co-expression network analysis (WGCNA) approach. Assigned mi-, lnc-, and m-modules used to construct the integrated regulatory networks and miRNA-lncRNA-mRNA regulatory sub-networks. Remarkably, we have identified 18 miRNAs, five lncRNAs, and seven TFs as key regulators of str. uberis-induced mastitis. Most of the genes introduced here, mainly involved in immune response, inflammation, and apoptosis, were new to mastitis. These findings may help to further elucidate the underlying mechanisms of bovine mastitis, and the discovered genes may serve as signatures for early diagnosis and treatment of the disease.

Long non-coding RNA KCNQ1OT1 alleviates postmenopausal osteoporosis by modulating miR-421-3p/mTOR axis

The prevention and treatment of postmenopausal osteoporosis (PMOP) is a significant public health issue, and non-coding RNAs are of vital importance in this process. In this study, we find that the long non-coding RNA potassium voltage-gated channel subfamily Q member 1 overlapping transcript 1 (lncRNA KCNQ1OT1) can alleviate the ovariectomy-induced (OVX) PMOP in vivo. We determined that over-expression of KCNQ1OT1 could enhance functions of MC3T3-E1 cells, whereas an opposite trend was observed when KCNQ1OT1 was knocked down. Subsequently, miR-421-3p targeting KCNQ1OT1 was detected through a database search, and RNA fluorescent in situ hybridization, RNA immunoprecipitation, dual luciferase reporter assays all verified this relationship. Notably, KCNQ1OT1 stifled the miR-421-3p expression. The inhibition of proliferation, migration, and osteogenic differentiation caused by KCNQ1OT1 knock-down were reversed by an miR-421-3p inhibitor, further confirming the above findings. We verified that miR-421-3p specifically targeted the mammalian target of rapamycin (mTOR), and miR-421-3p inhibitor could reverse the negative effects of small interfering RNA of mTOR (si-mTOR) on MC3T3-E1 cells. Finally, osteoblasts isolated and cultured from OVX mice model and control mice also confirmed the observed trend. In combination, results mentioned above reveal that KCNQ1OT1 regulates MC3T3-E1 cell functions by regulating the miR-421-3p/mTOR axis.

Molecular mechanism of microRNAs regulating apoptosis in osteosarcoma

Osteosarcoma is a primary malignant bone tumor with no effective treatment. Apoptosis, one of the programmed cell death, is any pathological form of cell death mediated by intracellular processes. Under the pathological state, the de-regulated regulation of apoptosis can disrupt the balance between cell proliferation and death, causing osteosarcoma proliferation and metastasis. As carcinogenic or tumor suppressor factors, microRNAs (miRNAs) regulate apoptosis of osteosarcoma cells by regulating apoptosis-related genes and apoptosis-related signaling pathways, such as mitochondrial apoptosis pathway, death receptor pathway, and endoplasmic reticulum pathway. Meanwhile as these abnormal miRNAs can be stored and transported by exosomes, detecting exosomes can be seen an effective method to diagnose osteosarcoma in the early stage. This review provides the current knowledge of miRNAs and their target genes related to the apoptosis of osteosarcoma, summarizes abnormal expression and regulation of miRNAs and signaling pathways in osteosarcoma and prospects the detection of exosome as a method for early diagnosis of osteosarcoma.

CircSEC24A (hsa_circ_0003528) interference suppresses epithelial-mesenchymal transition of hepatocellular carcinoma cells via miR-421/MMP3 axis

Accumulating evidence indicates that circular RNAs (circRNAs) function as conclusive modulators in diverse tumors, including in hepatocellular carcinoma (HCC). Nonetheless, knowledge of the latent mechanisms involving circRNAs in HCC development is insufficient. circSEC24A (hsa_circ_0003528) was discovered by microarray analysis of patients with HCC. Binding sites between circSEC24A, miR-421, miR-421 and matrix metalloproteinase 3 (MMP3) were predicted using online bioinformatics tools. Interactions involving miRNA and target genes or circRNAs were verified by luciferase reporter-gene and RNA pull-down assays. Two HCC cell lines (HCCLM3 and Hep3B) and normal THLE-2 liver cells were used for in vitro experiments. miRNA and mRNA expression levels were detected by RT-qPCR, and protein expression was measured by western blotting. Cell proliferation was evaluated using Cell Counting Kit 8 (CCK-8) assays along with colony formation assays. Cell invasion and migration were determined using the Transwell and wound healing migration assays. A xenograft model was used to evaluate the role of circSEC24A in vivo. circSEC24A expression was significantly upregulated in HCCLM3 and Hep3B cells. Silencing circSEC24A mitigated the proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) of HCC cells, which was abrogated by downregulation of miR-421. Meanwhile, MMP3 could bind to miR-421 to decrease the functional effects of miR-421 and induce tumor metastasis. Knockdown of cicSEC24A suppressed tumor growth in vivo. circSEC24A interference suppressed HCC cell EMT by sponging miR-421, further regulating MMP3, and inhibiting tumor growth in vivo. Therefore, circSEC24A could represent a potential target for HCC patient treatment.

SPINKs in Tumors: Potential Therapeutic Targets

The serine protease inhibitor Kazal type (SPINK) family includes SPINK1-14 and is the largest branch in the serine protease inhibitor family. SPINKs play an important role in pancreatic physiology and disease, sperm maturation and capacitation, Nager syndrome, inflammation and the skin barrier. Evidence shows that the unregulated expression of SPINK1, 2, 4, 5, 6, 7, and 13 is closely related to human tumors. Different SPINKs exhibit various regulatory modes in different tumors and can be used as tumor prognostic markers. This article reviews the role of SPINK1, 2, 4, 5, 6, 7, and 13 in different human cancer processes and helps to identify new cancer treatment targets.

Latent-transforming growth factor β-binding protein 2 accelerates cardiac fibroblast apoptosis by regulating the expression and activity of caspase-3

Cardiac fibrosis is a core process in the development of heart failure. However, the underlying mechanism of cardiac fibrosis remains unclear. Recently, a study found that in an isoproterenol (ISO)-induced cardiac fibrosis animal model, there is high expression of latent-transforming growth factor β-binding protein 2 (LTBP2) in cardiac fibroblasts. Whether LTBP2 serves a role in cardiac fibrosis is currently unknown. In the present study, mouse cardiac fibroblasts (MCFs) were treated with 100 µM/l ISO for 24, 48, or 72 h, and small interfering RNAs (siRNAs) were used to knockdown LTBP2. Reverse transcription-quantitative PCR and western blotting were used to determine gene and protein expression levels, respectively. Caspase-3 serves a key role in cell apoptosis and is related to cardiac fibrosis-induced heart failure. Caspase-3 activity was therefore determined using a caspase-3 assay kit, CCK8 was used to determine the rate of cell proliferation and apoptosis rates were quantified using a cell death detection ELISA kit. The present study demonstrated that cell apoptosis and LTBP2 expression increased in MCFs treated with 100 µM/l ISO in a time-dependent manner. Expression and activity of caspase-3 also increased in MCFs treated with 100 µM/l ISO for 48 h compared with the control group. In addition, ISO stimulation-induced MCF apoptosis, along with the increased expression of caspase-3 were partly abolished when LTBP2 was knocked down. In conclusion, LTBP2 expression increased in ISO-treated MCFs and accelerated mouse cardiac fibroblast apoptosis by enhancing the expression and activity of caspase-3. LTBP2 may therefore be a potential therapeutic target for treating patients with cardiac fibrosis.

Circular RNA_CNST Promotes the Tumorigenesis of Osteosarcoma Cells by Sponging miR-421

Circular RNAs (circRNAs) act crucial roles in the progression of multiple malignancies including osteosarcoma (OS). But, the underlying mechanisms by which hsa_circ_0017311 (circCNST) contributes to the tumorigenesis of OS remain poorly understood. Our present study aimed to explore the role and mechanisms of circCNST in OS tumorigenesis. The differentially expressed circRNAs were identified by the Gene Expression Omnibus database. The association of circCNST with clinicopathological features and prognosis in patients with OS was analyzed by RNA fluorescence in situ hybridization (FISH) and quantitative real-time polymerase chain reaction (PCR) analysis. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), colony formation assays, and a xenograft tumor model were conducted to assess the role of circCNST in OS cells in vitro and in vivo. CircCNST-specific binding with miR-421 was confirmed by FISH, luciferase gene report, and RNA immunoprecipitation assays. As a result, we found that the expression levels of circCNST were dramatically increased in OS tissues and cell lines as compared with the adjacent normal tissues, and it was associated with tumor size and poor survival in OS patients. Knockdown of circCNST repressed cell viability, colony formation, and xenograft tumor growth, while restored expression of circCNST reversed these effects. Furthermore, circCNST was colocalized with miR-421 in the cytoplasm and acted as a sponge of miR-421, which attenuated circCNST-induced proliferation-promoting effects in OS cells by targeting SLC25A3. In conclusion, our findings demonstrate that circCNST promotes the tumorigenesis of OS cells by sponging miR-421, and provides a potential biomarker for patients with OS.

MiR-421 regulates goat intramuscular preadipocytes differentiation via targeting FGF13

As a member of the MicroRNA s (miRNAs) family, miR-421 has been widely studied in regulating the proliferation and apoptosis of cancer cells a. However, there are still no reports on miR-421 in regulating adipocyte differentiation and its related mechanisms. Accordingly, this study aimed to investigate the potential involvement of miR-421 in goat intramuscular preadipocytes (P_IMA). The expression level of miR-421 was measured via quantitative real-time PCR during goat P_IMA differentiation. And the effects of miR-421 on goat P_IMA differentiation were studied by liposome transfection, Oil red O staining and qRT-PCR. Furthermore, the miR-421 target was searched and the underlying mechanism was clarified by luciferase reporter assay and rescue experiment. Our results showed that inhibition of miR-421 could accumulation of lipid droplets by upregulation the expression level of AP2, LPL, C/EBPα and SREBP1. Further studies showed that fibroblast growth factor 13 (FGF13) was the direct target of miR-421. Knocking down of FGF13 expression could inhibit lipid droplet formation and down-regulated the expression of key adipogenic regulatory genes. In addition, the rescue experiment revealed that FGF13 is involved in miR-421-induced differentiation of goat P_IMA as a key factor. Overall, these findings indicate that miR-421 is a negative regulator in the progression of differentiation of goat P_IMA by inhibiting the expression of FGF13.

Investigation of anticancer activities of STA-9090 (ganetespib) as a second generation HSP90 inhibitor in Saos-2 osteosarcoma cells

Osteosarcoma is common childhood tumour type of the bone. Chemotherapy is the most important step in treatment of osteosarcoma. Despite advanced diagnosis methods and target specific cancer therapeutics, osteosarcoma has still a high mortality rate and a tendency to metastasize. Therefore, new therapeutic strategies are evaluated in osteosarcoma treatment in pre-clinical and clinical studies. In the last ten years, heat shock protein 90 (HSP90) has been important biological target to design target specific cancer drugs. HSP90 play vital roles in proper folding, stabilization and maintenance of oncogenic client proteins in tumorigenesis. Therefore, inhibition of HSP90 has been significant therapeutic aspects in cancer drug design. STA-9090 (ganetespib) is a second generation small molecule HSP90 inhibitor which blocks tumurogenesis in cancer cells. STA-9090 inhibited ATP hydrolysis and protein folding process of HSP90. In this study, STA-9090 decreased Saos-2 cell proliferation and IC₅₀ dose of STA-9090 was found out as 18.71 µM and 10.25 µM at 24 h and 48 h, respectively. STA-9090 inhibited HSP90 ATPase function and disrupted oncogenic client protein folding activity. Also, STA-9090 decreased protein level of the HSP90 in osteosarcoma cells. Expression analysis of osteosarcoma and bone metabolism related genes was performed by RT² Profiler PCR Array. This study has found the down-regulation of the expression levels of oncogenic genes: DKK1, TWIST1, WNT10B, WNT3A, RANK, RANKL, PTH, FGFR1, FGFR2, LTBP2, IL6, TGFβ1, MMP2 and SPARC genes, in STA-9090 treated Saso-2 cells. Furthermore, expression levels of osteosarcoma related genes, OPG, ERα, ERβ, IL15, BMP2 and BMP7, were found to have increased significantly. Biological activities of STA-9090 on Saos-2 cell line show its potential as a target specific drug to inhibit osteosarcoma and its metastasis.

Circ_WWC3 overexpression decelerates the progression of osteosarcoma by regulating miR-421/PDE7B axis

Background

Emerging evidence has shown that circular RNAs (circRNAs) are vital regulators in osteosarcoma (OS) progression. However, the effects of circ_WWC3 in OS have not been explored. In this research, the functions and mechanisms of circ_WWC3 in OS were investigated.

Methods

Quantitative reverse trancription polymerase chain reaction (qRT-PCR) was adopted to determine the levels of circ_WWC3, WW and WWC3 mRNA, miR-421, and phosphodiesterase 7B (PDE7B) mRNA. RNase R assay was used to determine the characteristic of circ_WWC3. Colony formation assay and 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay were applied for cell growth. Transwell assay was performed for cell migration and invasion. Flow cytometry analysis was utilized for cell apoptosis. Western blot assay was conducted for the levels of apoptosis-related proteins and PDE7B protein. Dual-luciferase reporter assay was carried out to analyze the targeting relationship between miR-421 and circ_WWC3 or PDE7B. The murine xenograft model was established to explore the effect of circ_WWC3 in vivo.

Results

Compared to normal tissues and cells, circ_WWC3 and PDE7B were downregulated in OS tissues and cells. Overexpression of circ_WWC3 or PDE7B suppressed OS cell growth, migration, and invasion and promoted apoptosis in vitro. Regarding the mechanism analysis, circ_WWC3 positively modulated PDE7B expression by targeting miR-421. MiR-421 overexpression restored the impacts of circ_WWC3 on OS cell growth, metastasis, and apoptosis. Inhibition of miR-421 repressed the malignant behaviors of OS cells by targeting PDE7B. In addition, circ_WWC3 inhibited the tumorigenicity of OS in vivo.

Conclusion

Circ_WWC3 overexpression slowed the development of OS by elevating PDE7B via sponging miR-421.

Upregulation of miR-421 predicts poor prognosis and promotes proliferation, migration, and invasion of papillary thyroid cancer cells

BACKGROUND

Papillary thyroid carcinoma (PTC) represents the most frequent subtype of thyroid cancer (TC) with poor prognosis mainly due to the severe invasion and metastasis. As an oncogene, microRNA-421 (miR-421) is involved in the development of various cancers. This study was to investigate the clinical significance of miR-421 in PTC and its effects on the biological function of PTC cells.

METHODS

The expression level of miR-421 in all tissues and PTC cell lines was measured by quantitative real-time polymerase chain reaction (qRT-PCR). Subsequently, the relationship between miR-421 expression and the clinicopathological feature was detected by chi-square analysis in 106 patients with PTC. In addition, Kaplan-Meier and multivariate Cox regression analysis were used to detect the survival time and the prognostic value of miR-421. Finally, the regulatory effect of miR-421 on the proliferation, migration, and invasion ability of PTC cells was detected by Cell Counting Kit (CCK-8) and Transwell assay.

RESULTS

Compared with all control groups, the expression of miR-421 was significantly increased in 106 patients tissues and PTC cell lines (p < 0.001). In addition, patients with miR-421 upregulated in PTC showed more positive lymph node metastasis (p = 0.011), positive tumor infiltration (p = 0.031), and TNM stage III/IV (p = 0.019), and when miR-421 expression level was elevated, the survival rate of PTC patients was poor (log-rank test, p = 0.023). Furthermore, miR-421 might be an independent prognostic biomarker for PTC (hazard ratio [HR] = 3.172, 95% CI = 1.071-9.393, p = 0.037). Finally, increased levels of miR-421 can significantly promote cell proliferation, migration, and invasion (p < 0.01).

CONCLUSION

miR-421 is a novel oncogene of PTC and is a valuable prognostic biomarker. Moreover, the upregulation of miR-421 enhances the proliferation, migration, and invasion of PTC cells.

Updates on the molecular genetics of primary congenital glaucoma (Review)

Primary congenital glaucoma (PCG) is one of the primary causes of blindness in children and is characterized by congenital trabecular meshwork and anterior chamber angle dysplasia. While being a rare condition, PCG severely impairs the quality of life of affected patients. However, the pathogenesis of PCG remains to be fully elucidated. It has previously been indicated that genetic factors serve a critical role in the pathogenesis of PCG, although patients with PCG exhibit significant genetic heterogeneity. Mutations in the cytochrome P450 family 1 subfamily B member 1 gene have been implicated in PCG and further genes that have been reported to be involved in PCG are myocilin, forkhead box C1, collagen type I α1 chain and latent transforming growth factor β binding protein 2. The present review aims to provide an up to date understanding of the genes associated with PCG and the use of molecular technologies in the identification of such genes and mutations. This may pave the way for the development of preventative methods, early diagnosis and improved therapeutic strategies in PCG.

miR-548d-3p inhibits osteosarcoma by downregulating KRAS

MicroRNAs (miRNAs) are known to be associated with certain cancers, including osteosarcoma. We examined osteosarcoma tissues and cell lines, and found that most expressed lower levels of miR-548d-3p than adjacent tissues and normal cell lines. KRAS was identified as a potential target gene of miR-548d-3p. In osteosarcoma cells, miR-548d-3p exerted tumor-suppressive effects by downregulating KRAS. Functional assays revealed that miR-548d-3p mimics dramatically reduced cell growth and migration in vitro. These results suggest that miR-548d-3p mimics could be applied for osteosarcoma treatment.