Long non coding RNA UCA1 contributes to the autophagy and survival of colorectal cancer cells via sponging miR-185-5p to up-regulate the WISP2/β-catenin pathway

The estimated number of new cases of colorectal cancer (CRC) will increase to 140 250 in 2018 worldwide. The long non-coding RNA (lncRNA) urothelial carcinoma-associated 1 (UCA1) has recently been shown to be dysregulated in CRC, which plays an important role in the progression of CRC. However, the biological role and the underling mechanism of UCA1 in the carcinogenesis of CRC remain unclear. Herein, we found that UCA1 was aberrantly upregulated in two CRC cell lines (SW620 and HT29) compared to colorectal cell CCD-18Co. UCA1 knockdown inhibited the apoptosis, growth and autophagy of CRC cell lines in vitro. Furthermore, UCA1 could act as an endogenous sponge by directly interacting with miR-185-5p and downregulation miR-185-5p expression. In addition, UCA1 could reverse the inhibitory effect of miR-185-5p on the growth and autophagy of CRC cells, which might be involved in the derepression of member 1 (WNT1)-inducible signaling pathway protein 2 (WISP2, a target gene of miR-185-5p) expression and the activation of the WISP2/β-catenin signaling pathway. In vivo, the present study elucidates a novel UCA1-miR-185-5p-WISP2-Wnt/β-catenin axis in CRC, which may help us to understand the pathogenesis and the feasibility of lncRNA-directed diagnosis and therapy of CRC.

The estimated number of new cases of colorectal cancer (CRC) will increase to 140 250 in 2018 worldwide.     

The microRNA-217 functions as a tumor suppressor and is frequently downregulated in human osteosarcoma

ObjectiveDysregulation of miRNA is always associated with cancer development and progression. Aberrant expression of miR-217 has been found in some types of cancer. However, its expression and function in osteosarcoma remain unclear. The aim of this study was to explore the effects of miR-217 in osteosarcoma tumorigenesis and development.MethodsThe expression level of miR-217 was quantified by real-time RT-PCR in human osteosarcoma cell lines and tissues. MTT, flow cytometric, transwell invasion and migration assays, and tumorigenicity in vivo were adopted to observe the effects of miR-217 on MG-63 cell phenotypes.ResultsMiR-217 was significantly downregulated in osteosarcoma cell lines and clinical specimens. Decreased miR-217 expression was significantly associated with large tumor size, positive distant metastasis, and advanced clinical stage. Low miR-217 expression in osteosarcoma was an independent predictor of poor survival. Overexpression of miR-217 can inhibit the proliferation, invasion, migration and promoted apoptosis of MG-63 cells in vitro and in vivo.ConclusionsThese findings indicate that miR-217 may act as a tumor suppressor in osteosarcoma and would serve as a novel therapeutic agent for miRNA-based therapy.     

Gas5 Exerts Tumor-suppressive Functions in Human Glioma Cells by Targeting miR-222

Aberrant expression of noncoding RNAs in glioma cells, including long noncoding RNAs (lncRNAs) and microRNAs, may participate in the progression of glioma. Encoded by Growth Arrest-Specific 5 (GAS5) gene, lncRNA Gas5 was reported to be a negative regulator for survival and proliferation of several cancers. Here, Gas5 is found to be downregulated in glioma specimens and U87 and U251 glioma cell lines. We showed that the introduction of Gas5 by plasmid transfection increased the expression of tumor suppressor Bcl-2-modifying factor (bmf) and Plexin C1 via directly targeting and reducing the expression of miR-222. Downregulated expression of miR-222 inhibited U87 and U251 cell proliferation and promoted the apoptosis by upregulating bmf. As downstream signaling molecules of bmf, Bcl-2 and Bax were involved in the process. Meanwhile, knockdown of miR-222 attenuated U87 and U251 cell migration and invasion by upregulating Plexin C1, and cofilin was a crucial regulator targeted by Plexin C1. Gas5 combined with the knockdown of miR-222 resulted in the smallest tumor volumes and the longest survivals of nude mice in vivo. In summary, we show that Gas5 suppresses tumor malignancy by downregulating miR-222, which may serve as a promising therapy for glioma.     

具核梭杆菌促进结直肠癌发病相关机制的研究进展

具核梭杆菌(fusobacterium nucleatum,Fn)与结直肠癌(colorectal cancer,CRC)发生有关。有研究发现人类CRC中有过量的Fn,并阐明了Fn在体外和小鼠模型中参与CRC发生可能的机制。Fn参与CRC癌变的机制主要包括:通过增加髓系来源的抑制细胞和减少自然杀伤细胞等发挥的免疫调节;由FadA、Fap2和脂多糖介导的毒力作用;促进肿瘤相关microRNA(如miR-21)表达;代谢作用。本文就Fn在CRC中的作用机制作一综述。     

Hsa_circ_0005100 regulates tumorigenicity of colorectal carcinoma via miR‐145‐5p/ MACC1 axis

BackgroundCircular RNAs (circRNAs) are a kind of RNA molecules involved in the regulation of cancer progression, including colorectal carcinoma (CRC); nevertheless, their regulation mode is blurry. In the present work, we attempted to reveal the characteristics of hsa_hsa_circ_0005100 in CRC.MethodsDifferential expressions of hsa_circ_0005100, FMN2 mRNA, microRNA‐145‐5p (miR‐145‐5p), and MACC1 were indicated by qRT‐PCR and Western blot. The capacities of cell growth and motility were validated by the MTT assay, flow cytometry assay, EdU assay, colony formation assay, and transwell assay. Moreover, the targeted relationship of miR‐145‐5p and hsa_circ_0005100 or MACC1 was distinguished by dual‐luciferase reporter assay. The animal experiment was implemented to confirm the influence of hsa_circ_0005100 on tumorigenesis in vivo.ResultsHsa_circ_0005100 and MACC1 expression levels were increased, but miR‐145‐5p expression level was diminished in CRC. Hsa_circ_0005100 knockdown repressed cell proliferation, cell cycle, migration, and invasion, while expedited cell apoptosis in CRC cells. Furthermore, miR‐145‐5p was disclosed to block CRC via overturning MACC1. Hsa_circ_0005100 targeted miR‐145‐5p to modulate MACC1. Additionally, hsa_circ_0005100 knockdown also attenuated tumorigenesis in vivo.ConclusionHsa_circ_0005100 was a vital regulator in the development of CRC by miR‐145‐5p/MACC1 axis, which deepened the understanding of CRC pathogenesis from circRNA insights.     

Targeting miR-21 for the Therapy of Pancreatic Cancer

Despite tremendous efforts worldwide from clinicians and cancer scientists, pancreatic ductal adenocarcinoma (PDA) remains a deadly disease for which no cure is available. Recently, microRNAs (miRNAs) have emerged as key actors in carcinogenesis and we demonstrated that microRNA-21 (miR-21), oncomiR is expressed early during PDA. In the present study, we asked whether targeting miR-21 in human PDA-derived cell lines using lentiviral vectors (LVs) may impede tumor growth. We demonstrated that LVs-transduced human PDA efficiently downregulated miR-21 expression, both in vitro and in vivo. Consequently, cell proliferation was strongly inhibited and PDA-derived cell lines died by apoptosis through the mitochondrial pathway. In vivo, miR-21 depletion stopped the progression of a very aggressive model of PDA, to induce cell death by apoptosis; furthermore, combining miR-21 targeting and chemotherapeutic treatment provoked tumor regression. We demonstrate herein for the first time that targeting oncogenic miRNA strongly inhibit pancreatic cancer tumor growth both in vitro and in vivo. Because miR-21 is overexpressed in most human tumors; therapeutic delivery of miR-21 antagonists may still be beneficial for a large number of cancers for which no cure is available.     

Odontogenic ameloblast-associated protein (ODAM) inhibits human colorectal cancer growth by promoting PTEN elevation and inactivating PI3K/AKT signaling

Odontogenic ameloblast-associated protein (ODAM), an acidic matricellular protein, has been implicated in several epithelial neoplasms. However, its biological functions and molecular mechanisms in cancer progression, particular colorectal carcinoma (CRC), remain unknown. Here we demonstrated that ODAM was significantly down-regulated in CRC tissues compared with their normal counterparts. Then, we established that ODAM expression level was closely correlated with CRC development and patient prognosis. The abnormal expression of ODAM dramatically affected CRC cell growth in vitro and in vivo. We further revealed that the inhibitory effects of ODAM on CRC cell growth were associated with PTEN elevation and PI3K/AKT signaling inactivation. Furthermore, we determined that silencing of PTEN expression yielded recovery of AKT activity in ODAM-expressing CRC cells. Our study suggests matricellular protein ODAM may serve as a novel prognostic marker and act as a CRC growth suppressor.     

miR-217 targeting Wnt5a in osteosarcoma functions as a potential tumor suppressor

Osteosarcoma (OS) is the most common malignant bone tumor in children and young adults, however roles of microRNAs (miRNAs) in OS is still unclear. miR-217 is recently widely studied in various cancers, but not including OS. This study is aimed to investigate the expression and cellular function of miR-217 in OS. The data showed that miR-217 expression was consistently lower in OS tissues and cell lines than the normal controls. Restoration of miR-217 expression in MG-63 and U2OS cells could inhibit cell proliferation, migration and invasion, and induced apoptosis. Bioinformatic prediction suggested that Wnt5a is a target gene of miR-217. Using luciferase assay, mRNA and protein expression analysis, it was verified that Wnt5a was a target gene of miR-217 in OS cells. Restored expression of Wnt5a weakened miR-217-mediated suppression of tumor progression. Taken together, our data indicate that miR-217 functions as a tumor suppressor in OS by suppressing Wnt5a expression.     

NLK,a novel target of miR-199a-3p,functions as a tumor suppressor in colorectal cancer

We previously reported that miR-199a-3p is a newly biomarker for diagnosis and novel prognostic indicator in colorectal cancer. However, the miR-199a-3p regulatory mechanism and its target genes are still unclear. In our present study, we demonstrated miR-199a-3p could directly target 3′-UTR of NLK gene by luciferase reporter assay and western blot analysis. We detected NLK expressions in 92 colorectal cancer cases to evaluate its clinicopathologic characteristics in colorectal cancer. Our results showed that NLK expression was significantly downregulated in cancer tissues than NATs, and NLK low-expression was associated with lymph node metastasis, venous invasion, liver metastasis and the TNM stage (P < 0.05). Moreover, Kaplan–Meier analysis showed that low expression of NLK correlated with a shorter overall survival rates of patients with CRC (P < 0.05). In vitro, we also found that NLK suppressed the biological behaviors of colorectal cancer cells, including the abilities of cell proliferation, clone formation, wound healing, migration and invasion (P < 0.05), while overexpression of NLK increased the apoptotic rate of colorectal cancer cells. All these results suggested that NLK was an identified miR-199a-3p target gene and functioned as a tumor suppressor gene in colorectal cancer. NLK could be a novel direction for developing diagnostic and therapeutic approaches in colorectal cancer.     

Up-regulation of miR-592 correlates with tumor progression and poor prognosis in patients with colorectal cancer

miR-592, as a potential biomarker, has been linked to several cancers. However, the expression level and prognostic value of miR-592 in CRC have not been elucidated. In this study, we detected the miR-592 expression in CRC serum, tumor tissues, adjacent non-tumor tissues (NATs) and four colorectal cancer cell lines by RT-PCR. Our data proved that miR-592 expression was up-regulated in clinical CRC serum and tissues (P < 0.05). Serum or tissue miR-592 in CRC metastatic patients also maintained a high level, compared to that in non-metastatic CRC patients (P < 0.05). After radical surgery, postoperative serum miR-592 level in CRC patients significantly decreased (P < 0.05). Our clinicopathological analysis revealed that high miR-592 was significant associated with the tumor size (P = 0.008), TNM stage (P = 0.026), distant metastasis (P = 0.004) and preoperative CEA level (P = 0.022), which led to a shorter overall survival rate in CRC patients (P = 0.032). Furthermore, we designed and transfected miR-592 mimics or inhibitors into the corresponding CRC lines, and our experiments in vitro demonstrated that miR-592 could promote cell proliferation, wound healing and invasion ability of CRC cells (P < 0.05), while miR-592 did not influence the CRC cell apoptosis (P > 0.05). All these results suggested that miR-592 functioned as a novel and potential carcinogen-initiated and metastasis-related biomarker in CRC, and down-regulation of miR-592 might be considered as a potentially significant molecular treatment strategy for CRC patients.     

Systemic Delivery of Synthetic MicroRNA-16 Inhibits the Growth of Metastatic Prostate Tumors via Downregulation of Multiple Cell-cycle Genes

Recent reports have linked the expression of specific microRNAs (miRNAs) with tumorigenesis and metastasis. Here, we show that microRNA (miR)-16, which is expressed at lower levels in prostate cancer cells, affects the proliferation of human prostate cancer cell lines both in vitro and in vivo. Transient transfection with synthetic miR-16 significantly reduced cell proliferation of 22Rv1, Du145, PPC-1, and PC-3M-luc cells. A prostate cancer xenograft model revealed that atelocollagen could efficiently deliver synthetic miR-16 to tumor cells on bone tissues in mice when injected into tail veins. In the therapeutic bone metastasis model, injection of miR-16 with atelocollagen via tail vein significantly inhibited the growth of prostate tumors in bone. Cell model studies indicate that miR-16 likely suppresses prostate tumor growth by regulating the expression of genes such as CDK1 and CDK2 associated with cell-cycle control and cellular proliferation. There is a trend toward lower miR-16 expression in human prostate tumors versus normal prostate tissues. Thus, this study indicates the therapeutic potential of miRNA in an animal model of cancer metastasis with systemic miRNA injection and suggest that systemic delivery of miR-16 could be used to treat patients with advanced prostate cancer.     

Baculovirus-Mediated miRNA Regulation to Suppress Hepatocellular Carcinoma Tumorigenicity and Metastasis

MicroRNA 122 (miR-122) is a tumor suppressor for hepatocellular carcinoma (HCC) but is lowly expressed in HCC cells. MiR-151 is aberrantly overexpressed in HCC cells and promotes HCC metastasis yet its roles on HCC tumorigenicity are unknown. To combat HCC tumorigenicity/metastasis, we developed Sleeping Beauty (SB)-based hybrid baculovirus (BV) vectors that expressed (i) miR-122 precursors (pre-miR-122), (ii) miR-151 sponges, or (iii) pre-miR-122 and miR-151 sponges. Transduction of aggressive HCC cells (Mahlavu) with the pre-miR-122-expressing BV tremendously enhanced miR-122 levels for >6 weeks, suppressed the levels of downstream effectors (e.g., ADAM10 and Bcl-w), proliferation, anchorage-independent growth, motility and migration/invasion in vitro. Intratumoral injection of the pre-miR-122-expressing BV attenuated the HCC growth/metastasis. The miR-151 sponges-expressing BV diminished the miR-151 levels for 6 weeks, enhanced RhoGDIA expression, suppressed RhoGTPases, as well as motility and migration/invasion of Mahlavu cells. Intratumoral injection of the miR-151 sponge-expressing BV impeded not only HCC metastasis but also cell proliferation, MMP expression and tumor growth in vivo. The BV co-expressing pre-miR-122 and miR-151 sponges also simultaneously enhanced miR-122 expression and inhibited miR-151, and conferred antitumor/anti-metastasis effects albeit lack of synergism. These data implicate the potentials of the SB-based hybrid BV for persistently modulating miRNA and suppressing HCC tumorigenicity/metastasis.     

Antitumor Activity of miR-1280 in Melanoma by Regulation of Src

MicroRNAs (miRNAs) play a key role in cancer progression by coordinately repressing target genes involved in cell proliferation, migration, and invasion. miRNAs regulate gene expression by repressing translation or directing sequence-specific degradation of complementary mRNA. Here, we report that expression of miR-1280 is significantly suppressed in human melanoma specimens when compared with nevi, and in human melanoma cell lines when compared with cultured normal human melanocytes. The proto-oncogene Src was identified as a target of miR-1280 action. Levels of Src expression were significantly higher in melanoma samples and cell lines than in nevi and normal melanocytes. miR-1280 overexpression significantly suppressed the luciferase activity of reporter plasmids containing the full-length 3′ untranslated region of Src. miR-1280-mediated suppression of Src led to substantial decreases in melanoma cell proliferation, cell cycle progression, invasion, as well as induced melanoma cell apoptosis. The effects of miR-1280 overexpression on melanoma cell proliferation and growth were reversed by Src overexpression. Intratumoral delivery of miR-1280 significantly suppressed melanoma cell growth in vivo. Our results demonstrate a novel role for miR-1280 as a tumor suppressor in melanoma, identify the Src signaling pathway as a target of miR-1280 action, and suggest a potential therapeutic role for miR-1280 in melanoma.     

Development of microRNA-145 for therapeutic application in breast cancer

MicroRNAs, small non-coding RNAs, are key regulators of tumorigenesis and cancer metastasis through inhibition of gene expression. Therefore, there is increasing interest in developing anti-cancer therapies using microRNAs. In this study, we determined the therapeutic potency of microRNA-145(miR-145) against breast cancer. We found a reverse-correlation between the expression of miR-145 and its target genes, such as fascin-1, c-myc, SMAD2/3 and IGF-1R in breast cancer cell lines and breast cancer patient tissues. Transfected miR-145 mimicking double-stranded oligonucleotides was directly reduced cell proliferation and motility via interaction with 3′UTR of target gene and also indirectly regulates Wnt signaling. An inhibitor of miR-145 nullified this decreasing effect of miR-145 on cell proliferation and motility. We prepared an adenoviral constructed miR-145(Ad-miR-145) and subjected it to breast cancer cells in vitro and orthotopic breast cancer mice in vivo. Ad-miR-145 suppressed cell growth and motility in both the in vitro and in vivo systems. Furthermore, a treatment combining Ad-miR-145 with 5-FU significantly showed anti-tumor effects, compared to treating alone. In conclusion, this study demonstrated that miR-145 suppresses tumor growth by inhibition of multiple tumor survival effectors, and more we suppose that miR-145 is potentially useful in the therapy of breast cancers.     

MiR-125a regulates ovarian cancer proliferation and invasion by repressing GALNT14 expression

Increasing evidence has suggested that dysregulation of microRNAs (miRNAs) could contribute to tumor progression. The miR-125a was downregulated in several types of cancer, however, the molecular mechanism of miR-125a in the ovarian cancer remains unclear. The aim of the paper was to reveal the mechanism of miR-125a regulating cell proliferation and metastasis in ovarian cancer. In this study, western blotting, immunohistochemistry and serum-ELISA assay revealed that polypeptide N-acetylgalactosaminyl transferase 14 (GALNT14) expression was upregulated and correlated with the cancer stage in ovarian cancer. The expression levels of miR-125a were downregulated and negatively related to GALNT14 expression in clinical ovarian cancer tissues. Moreover, luciferase reporter assay identified polypeptide N-acetylgalactosaminyl transferase 14 (GALNT14) as a direct target of miR-125a, and overexpression of miR-125a markedly reduced the expression of GALNT14 in ovarian cancer. Functional characterization of miR-125a was accomplished by reconstitution of miR-125a and silencing GALNT14 expression in ovarian cancer cells to determine changes in proliferation and invasion. The MTT assay and transwell assay revealed that miR-125a transfectant significantly inhibits cell proliferation and invasion, by repressing GALNT14 expression. Furthermore, the gelatin zymography assay miR-125a mimics and GALNT14 siRNA suppressed the activity of MMP2 and MMP9. Taken together, our findings show that miR-125a functions as tumor suppressor in ovarian cancer by targeting GALNT14, and miR-125a may therefore serve as a biomarker for diagnosis and therapeutics in ovarian cancer.     

POM121 overexpression is related to a poor prognosis in colorectal cancer

ABSTRACT

Background: Nuclear pore membrane protein 121 (POM121) plays a crucial role in nucleocytoplasmic transport, but its significance in tumorigenesis and the progression of colorectal cancer (CRC) remains unknown. The aim of this study was to evaluate the relationship between POM121 and CRC.

Methods: POM121 expression in colorectal tissues was analyzed at both the gene and protein levels. We investigated the connection between POM121 expression and clinicopathological features, as well as overall survival. A gene set enrichment analysis (GSEA) was performed, and a protein-protein interaction (PPI) network was constructed to determine the mechanism of POM121 in CRC.

Results: CRC tissues displayed a striking increase in POM121 expression compared with colonitis and pericarcinomatous mucosa tissues (66.61% vs 24.36% vs 24.11%, respectively, p < 0.0167). POM121 overexpression was significantly associated with lymph node metastasis, distant metastasis, TNM stage, venous invasion, perineural invasion, preoperative CEA and CA19-9 levels, and Ki67 expression. CRC patients with high POM121 levels tended to have poor overall survival rates. POM121 may participate in the regulation of the cell cycle and DNA repair in CRC.

Conclusions: Our results suggest that POM121 has the potential to serve as a novel prognostic biomarker in CRC patients.     

Hsa_hsa_circ_0081069 promotes the progression of colorectal cancer through sponging miR‐665 and regulating E2F3 expression

BackgroundCircular RNAs (circRNAs) have been implicated in the initiation and development of various cancers. This study explored the potential contribution of hsa_hsa_circ_0081069 in the progression of colorectal cancer (CRC).MethodsThe gene expression was analyzed by qRT‐PCR. Functional roles of hsa_circ_0081069 were examined by shRNA‐mediated silencing using CCK‐8 proliferation assay, Transwell migration and invasion assay, tube formation assay. The tumorigenesis and metastasis of CRC cells were assess in a xenograft mouse model.ResultsHsa_circ_0081069 was significantly upregulated in CRC tissues and cells. Hsa_circ_0081069 knockdown suppressed the proliferation, migration and invasion in CRC cells, as well as the angiogenesis. Silencing hsa_circ_0081069 also impaired the tumorigenesis of CRC cells in a xenograft mouse model. Furthermore, miR‐665 was identified as an interacting partner of hsa_circ_0081069, which was negatively regulated by hsa_circ_0081069. miR‐665 targeted the mRNA of E2F3 to suppress its expression. We further demonsatred that miR‐665/E2F3 axis mediated the functional role of hsa_circ_0081069 in regulating the malignant phenotype of CRC cells.ConclusionsCollectively, our study suggests that hsa_circ_0081069 could serve as a prognostic marker in progression of CRC. Targeting hsa_circ_0081069 and miR‐665/E2F3 axis could serve as potential therapeutic strategies for CRC treatment.