MiR-34b inhibits the proliferation and promotes apoptosis in colon cancer cells by targeting Wnt/β-catenin signaling pathway

Sirtuin1 inhibits calcium oxalate crystal-induced kidney injury by regulating TLR4 signaling and macrophage-mediated inflammatory activation

Sirtuin1 (Sirt1) activation significantly attenuated calcium oxalate (CaOx) crystal deposition and renal inflammatory injury by regulating renal immune microenvironment. Here, to elucidate the molecular mechanism underlying the therapeutic effects of Sirt1 on macrophage related inflammation and tubular epithelial cells (TECs) necrosis, we constructed a macrophage and CaOx monohydrate (COM)-stimulated tubular cell co-culture system to mimic immune microenvironment in kidney and established a mouse model of CaOx nephrocalcinosis in wild-type and myeloid-specific Sirt1 knockout mice. Target prediction analyses of Gene Expression Omnibus Datasets showed that only miR-34b-5p is regulated by lipopolysaccharides and upregulated by SRT1720 and targets the TLR4 3'-untranslated region. In vitro, SRT1720 suppressed TLR4 expression and M1 macrophage polarization and decreased reactive oxygen species (ROS) production and mitochondrial damage in COM-stimulated TECs by targeting miR-34b-5p. Mechanically, Sirt1 promoted miR-34b-5p expression by suppressing the tri-methylation of H3K27, which directly bound to the miR-34b-5p promoter and abolished the miR-34b-5p transcription. Furthermore, loss of Sirt1 aggravated CaOx nephrocalcinosis-induced inflammatory and oxidative kidney injury, while AgomiR-34b reversed these effects. Therefore, our data suggested that Sirt1 inhibited TLR4 signaling and M1 macrophage polarization and decreased inflammatory and oxidative injury of TECs in vitro and in vivo.

In vitro study of miRNA-369-3p targeting TCF4 regulating the malignant biological behavior of colon cancer cells

Background

Colorectal carcinoma (CRC) is a common malignant tumor of the digestive tract. It is characterized by a high degree of malignancy, early metastasis and poor prognosis. Studies have shown the effect of miR-369-3p on the biological function of a variety of tumors. However, the mechanism by which miR-369-3p and its potential target genes participate in the pathogenesis of CRC has not been elucidated. This study aims to study the relationship between miR-369-3p and transcription factor 4 (TCF4), to reveal the mechanism of the occurrence and development of CRC, and to provide a promising target for the treatment of CRC.

Methods

Real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect the miR-369-3p levels in CRC tissues and cells. miR-369-3p mimics and/or TCF4 overexpression vectors were transfected into SW480 cells. The expression of miR-369-3p and TCF4 mRNA was detected using RT-qPCR. Bioinformatics analysis predicted the binding site of miR-369-3p to the TCF4 3'UTR, and the targeting relationship was verified by a dual luciferase reporter gene assay. Cell proliferation and invasion were investigated by labeled immunofluorescence assay using BrdU antibody and Transwell assay. The oxidative stress ability of cells was determined by commercial kits. The levels of proteins related to cell proliferation and invasion were measured by western blotting.

Results

The level of miR-369-3p was significantly down-regulated in CRC tissues and cell lines, especially in SW480 cells (P<0.05). The expression of TCF4 was negatively correlated with that of miR-369-3p. High levels of miR-369-3p targeting TCF4 suppressed cell proliferation and downregulated the protein expression of Ki67 and PCNA (P<0.05). Overexpressed miR-369-3p binding TCF4 inhibited cell invasion and decreased the protein levels of vascular endothelial growth factor (VEGF) and E-cadherin (P<0.05). Furthermore, upregulation of miR-369-3p increased the activity of superoxide dismutase (SOD) while decreasing the content of malondialdehyde (MDA) and activity of lactate dehydrogenase (LDH) by blocking the expression of TCF4 (P<0.05).

Conclusions

MiR-369-3p inhibits the proliferation, invasion and oxidative stress of CRC cells by targeting TCF4, thus defining miR-369-3p as a potential target for the diagnosis and treatment of CRC.

Non-coding RNA-based therapeutics in cancer therapy: An emphasis on Wnt/β-catenin control

Non-coding RNA transcripts are RNA molecules that have mainly regulatory functions and they do not encode proteins. microRNAs (miRNAs), lncRNAs and circRNAs are major types of this family and these epigenetic factors participate in disease pathogenesis, especially cancer that their abnormal expression may lead to cancer progression. miRNAs and lncRNAs possess a linear structure, whereas circRNAs possess ring structures and high stability. Wnt/β-catenin is an important factor in cancer with oncogenic function and it can increase growth, invasion and therapy resistance in tumors. Wnt upregulation occurs upon transfer of β-catenin to nucleus. Interaction of ncRNAs with Wnt/β-catenin signaling can determine tumorigenesis. Wnt upregulation is observed in cancers and miRNAs are able to bind to 3'-UTR of Wnt to reduce its level. LncRNAs can directly/indirectly regulate Wnt and in indirect manner, lncRNAs sponge miRNAs. CircRNAs are new emerging regulators of Wnt and by its stimulation, they increase tumor progression. CircRNA/miRNA axis can affect Wnt and carcinogenesis. Overall, interaction of ncRNAs with Wnt can determine proliferation rate, migration ability and therapy response of cancers. Furthermore, ncRNA/Wnt/β-catenin axis can be utilized as biomarker in cancer and for prognostic applications in patients.

S-Adenosylmethionine Inhibits Colorectal Cancer Cell Migration through Mirna-Mediated Targeting of Notch Signaling Pathway

Metastasis is a leading cause of mortality and poor prognosis in colorectal cancer (CRC). Thus, the identification of new compounds targeting cell migration represents a major clinical challenge. Recent findings evidenced a central role for dysregulated Notch in CRC and a correlation between Notch overexpression and tumor metastasis. MicroRNAs (miRNAs) have been reported to cross-talk with Notch for its regulation. Therefore, restoring underexpressed miRNAs targeting Notch could represent an encouraging therapeutic approach against CRC. In this context, S-adenosyl-L-methionine (AdoMet), the universal biological methyl donor, being able to modulate the expression of oncogenic miRNAs could act as a potential antimetastatic agent. Here, we showed that AdoMet upregulated the onco-suppressor miRNAs-34a/-34c/-449a and inhibited HCT-116 and Caco-2 CRC cell migration. This effect was associated with reduced expression of migration-/EMT-related protein markers. We also found that, in colorectal and triple-negative breast cancer cells, AdoMet inhibited the expression of Notch gene, which, by luciferase assay, resulted the direct target of miRNAs-34a/-34c/-449a. Gain- and loss-of-function experiments with miRNAs mimics and inhibitors demonstrated that AdoMet exerted its inhibitory effects by upregulating miRNAs-34a/-34c/-449a. Overall, these data highlighted AdoMet as a novel Notch inhibitor and suggested that the antimetastatic effects of AdoMet involve the miRNA-mediated targeting of Notch signaling pathway.

Mesenchymal Stem Cell-derived Extracellular Vesicles Transmitting MicroRNA-34a-5p Suppress Tumorigenesis of Colorectal Cancer Through c-MYC/DNMT3a/PTEN Axis

Mesenchymal stem cell–derived extracellular vesicles (MSC-EV) can transport microRNAs (miRNAs) into colorectal cancer (CRC) cells, thus to inhibit the malignant phenotype of cancer cells. Whether MSC-EV could deliver miR-34a-5p to suppress CRC development was surveyed through the research. miR-34a-5p, c-MYC, DNA methyltransferase 3a (DNMT3a), and phosphatase and tensin homolog deleted on chromosome 10 (PTEN) expression were measured in CRC tissues and cell lines. miR-34a-5p and c-MYC expression were altered by transfection in HCT-116 cells. MSC-EV were transfected with miR-34a-5p- and c-MYC-related oligonucleotides and co-cultured with HCT-116 cells. HCT-116 cell growth after treatment was observed. Furthermore, the functional roles of miR-34a-5p and c-MYC were explored in vivo. The combined interactions of miR-34a-5p/c-MYC/DNMT3a/PTEN axis were assessed. miR-34a-5p and PTEN were downregulated while c-MYC and DNMT3a were upregulated in CRC. Depletion of miR-34a-5p drove while that of c-MYC restricted CRC cell growth. MSC-EV retarded CRC progression. Moreover, MSC-EV carrying overexpressed miR-34a-5p or depleted c-MYC further disrupted CRC cell progression. miR-34a-5p targeted c-MYC to regulate DNMT3a and PTEN. c-MYC overexpression abrogated EV-derived miR-34a-5p upregulation-induced effects on CRC. Restoring miR-34a-5p or depleting c-MYC in MSC-EV limited CRC tumor formation. MSC-EV-derived miR-34a-5p depresses CRC development through modulating the binding of c-MYC to DNMT3a and epigenetically regulating PTEN.

Integrated analysis of circRNA-miRNA-mRNA network reveals potential prognostic biomarkers for radiotherapies with X-rays and carbon ions in non-small cell lung cancer

Background

This work was aimed at exploring the regulatory network of non-coding RNA (ncRNA) especially circular RNA (circRNA) and microRNA (miRNA), in the sensitivity of non-small cell lung cancer (NSCLC) cells to low linear energy transfer (LET) X-ray and high-LET carbon ion irradiations.

Methods

The radioresistant NSCLC cell line A549-R11 was obtained from its parental cell line A549 through irradiation with X-rays of 2.0 Gy per fraction for 30 times. The sensitivities of A549, A549-R11 and H1299 cells exposed to X-rays and carbon ions were verified using the colony formation assay. A comprehensive circRNA-miRNA-mRNA network was constructed through the sequencing data in parental A549, acquired radioresistant A549-R11 and intrinsic radioresistant H1299 cells, and the network was further optimized according to the prognostic results from the TCGA and GEO databases.

Results

Based on high-throughput sequencing of circRNAs, we found that 40 circRNAs were up-regulated while 184 circRNAs were down-regulated in the intersection of the sets of A549-R11 and H1299 cells. Subsequently, a circRNA- miRNA-mRNA network, including 14 interactive pairs and 8 circRNAs, 4 overall survival-associated miRNAs, and 4 mRNAs, was constructed through the high-throughput data screening and bioinformatics methods.

Conclusions

Our results provide a complete understanding to the regulatory mechanism of the sensitivities to low-LET X-ray and high-LET carbon ion irradiations, and might be helpful to screen potential biomarkers for predicting the Carbon-ion radiotherapy (CIRT) and X-ray radiotherapy responses in NSCLC.

MicroRNA‑199a‑5p suppresses cell proliferation, migration and invasion by targeting ITGA3 in colorectal cancer

As a member of the integrin family, integrin α3β1 (ITGA3) has been linked to intercellular communication and serves an important role in the signaling among cells and the extracellular matrix. MicroRNA (miR)-199a-5p has been demonstrated to be related to the pathogenesis and progression of multiple malignant diseases. However, the biological functions of miR-199a-5p and ITGA3 in colorectal cancer (CRC) have rarely been reported. The aim of the present study was to explore the roles of miR-199a-5p and ITGA3 in CRC. Immunohistochemistry staining and western blotting were applied to detect the protein expression of ITGA3 in CRC tissues and cells. Reverse transcription-quantitative PCR was performed to investigate the expression of miR-199a-5p and ITGA3 mRNA. HCT-116 cells were transfected with miR-199a-5p mimics, mimics control, short hairpin RNA targeting ITGA3, or pcDNA-ITGA3 for the functional experiments. Dual luciferase reporter assay was applied to confirm whether miR-199a-5p targeted the 3′ untranslated region (3′UTR) of ITGA3. The MTT, Transwell and wound healing assays were used to evaluate the proliferation, invasion and migration of CRC cells. Immunofluorescence assay was used to monitor the epithelial-mesenchymal transition (EMT) biomarker expression. The results demonstrated downregulation of miR-199a-5p and upregulation of ITGA3 in CRC tissues and cell lines. miR-199a-5p mimics and knockdown of ITGA3 suppressed the proliferation, invasion and migration of CRC cells. Bioinformatics analysis and luciferase reporter assay indicated that miR-199a-5p targeted the 3′UTR of the ITGA3 transcript, and overexpression of ITGA3 reversed the tumor-suppressive effects of miR-199a-5p elevation. In addition, the immunofluorescence assay suggested that miR-199a-5p mimics suppressed the EMT of CRC cells, whereas the overexpression of ITGA3 restored this effect. In conclusion, miR-199a-5p may act as a tumor suppressor by targeting and negatively regulating ITGA3 in CRC.

Wnt-regulating microRNAs role in gastric cancer malignancy

Gastric cancer (GC) is responsible for high morbidity and mortality worldwide. This cancer claims fifth place among other cancers. There are a number of factors associated with GC development such as alcohol consumption and tobacco smoking. It seems that genetic factors play significant role in GC malignancy and progression. MicroRNAs (miRs) are short non-coding RNA molecules with negative impact on the expression of target genes. A variety of studies have elucidated the potential role of miRs in GC growth. Investigation of molecular pathways has revealed that miRs function as upstream modulators of Wnt signaling pathway. This signaling pathway involves in important biological processes such as cell proliferation and differentiation, and its dysregulation is associated with GC invasion. At the present review, we demonstrate that how miRs regulate Wnt signaling pathway in GC malignancy.

Effect of miR-205 on proliferation and migration of thyroid cancer cells by targeting CCNB2 and the mechanism

This study explored the target of miR-205 and the effect of miR-205 on the proliferation and migration regulating its target in thyroid cancer cells (TC). Twenty-five pairs of TC and adjacent tissues were collected after surgical resection. Real-time fluorescence quantitative PCR (qRT-PCR) was used to detect the expression of miR-205 in TC tissues and cells (SW579, B-CPAP, TPC-1, WRO). SW579 cells were transfected with miR-205 mimic, and SW579 cells with overexpression of miR-205 were constructed. The effects of miR-205 overexpression on the proliferation and migration of SW579 cells were observed by cell counting kit-8 (CCK-8) and Transwell assays, respectively. Luciferase reporter assay was further used to look for the target of miR-205 and to study the mechanism of miR-205 in the proliferation and migration of TC cells. Compared with normal tissues and cells, the expression of miR-205 was significantly reduced in TC tissues (t=3.47, P=0.031) and cells (t=5.41, P=0.016). Overexpression of miR-205 inhibited the proliferation (t=4.12, P=0.035) and migration (t=4.47, P=0.027) of SW579 cells. Luciferase reporter assays found that CCNB2 was a target gene of miR-205 (t=4.63, P=0.024), qRT-PCR and western blot assays confirmed there was negatively correlation between CCNB2 and miR-205 (t=3.55, P=0.029; t=2.86, P=0.043). CCNB2 overexpression reversed the inhibition of miR-205 on the proliferation (t=3.70, P=0.031) and migration (t=4.12, P=0.022) of SW579 cells. In conclusion, miR-205 inhibits the proliferation and migration of TC cells by targeting CCNB2, which may be a potential target of TC therapy.

MicroRNA-937 is overexpressed and predicts poor prognosis in patients with colon cancer

Background

Colon cancer is a heterogeneous tumor and a leading cause of cancer-related mortality. MicroRNA (miRNA) has been proposed as the biomarker in cancers. The aim of this study was to investigate the clinical significance and potential functional role of miR-937 in colon cancer.

Methods

In the present study, reverse transcription-quantitative polymerase chain reaction (qRT-PCR) was conducted to examine the expression levels of miR-937 in colon cancer tissues and cell lines. Kaplan-Meier curve and Cox regression analyses were used to determine the prognostic impact of miR-937 on survival. Cell Counting Kit-8 and Transwell assays were performed to examine cell proliferation, migration, and invasion, respectively.

Results

miR-937 was significantly upregulated in colon cancer tissues and cell lines. Clinical analysis results showed that miR-937 expression was associated with lymph node metastasis and TNM stage. Patients with high miR-937 expression predicted a shorter overall survival rate. Functionally, overexpression of miR-937 promoted cell proliferation, migration, and invasion, while inhibition of miR-937 inhibited these cellular behaviors in vitro.

Conclusions

These results suggested that miR-937 may act as a prognostic biomarker and a potential target for therapeutic strategy, as well as promote proliferation, migration, and invasion of colon cancer.