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Introduction: MicroRNAs (miRNAs) are single RNA molecules that act as global regulators of gene expression in mammalian cells and thus constitute attractive targets in treating cancer. Here we aimed to investigate the possible involvement of miRNA-141 (miR-141) in cervical cancer and to identify its potential targets in cervical cancer cell lines., Methods: The level of miR-141 in HeLa and C-33A cells has been assessed using the quantitative real-time PCR (qRT-PCR). A new miR-141 construct has been performed in a CMV promoter vector tagged with GFP. Using microarray analysis, we identified the potentially regulated genes by miR-141 in transfected HeLa cells. The protein profile of killer-like receptor C1 (KLRC1), KLRC3, carcinoembryonic antigen-related cell adhesion molecule 3 (CAM3), and CAM6 was investigated in HeLa cells transfected with either an inhibitor, antagonist miR-141, or miR-141 overexpression vector using immunoblotting and flow cytometry assay. Finally, ELISA assay has been used to monitor the produced cytokines from transfected HeLa cells., Results: The expression of miR-141 significantly increased in HeLa and C-33A cells compared to the normal cervical HCK1T cell line. Transfection of HeLa cells with an inhibitor, antagonist miR-141, showed a potent effect on cancer cell viability, unlike the transfection of miR-141 overexpression vector. The microarray data of HeLa cells overexpressed miR-141 provided a hundred of downregulated genes, including KLRC1, KLRC3, CAM3, and CAM6. KLRC1 and KLRC3 expression profiles markedly depleted in HeLa cells transfected with miR-141 overexpression accompanied by decreasing interleukin 8 (IL-8), indicating the role of miR-141 in avoiding programmed cells death in HeLa cells. Likewise, CAM3 and CAM6 expression reduced markedly in miR-141 transduced cells accompanied by an increasing level of transforming growth factor beta (TGF-β), indicating the impact of miR-141 in cancer cell migration. The IntaRNA program and miRWalk were used to check the direct interaction and potential binding sites between miR-141 and identified genes. Based on this, the seeding regions of each potential target was cloned upstream of the luciferase reporter gene in the pGL3 control vector. Interestingly, the luciferase activities of constructed vectors were significantly decreased in HeLa cells pre-transfected with miR-141 overexpression vector, while increasing enormously in cells pre-transfected with miR-141 specific inhibitor., Conclusion: Together, these data uncover an efficient miR-141-based mechanism that supports cervical cancer progression and identifies miR-141 as a credible therapeutic target., (© 2024. The Author(s).)

It is well known that ox-LDL plays key roles in the development of atherosclerosis, partly by inducing vascular smooth muscle cells (VSMCs) proliferation. Recent findings have revealed that microRNAs, a class of small noncoding RNAs, could regulate cell proliferation in many physiological and pathological conditions. However, the role and function of miRNAs on ox-LDL induced VSMC proliferation are not fully elucidated. In this study, we showed that ox-LDL could suppress miR-141 expression and inhibition of miR-141 could promote VSMCs proliferation. Moreover, we found that PAPPA was the direct target gene of miR-141. Overexpression of PAPPA impaired the miR-141-induced inhibition of proliferation in the VSMCs. Taken together; miR-141 may play important roles in ox-LDL-induced abnormal proliferation of the VSMC.

Background: MiR-141 and long noncoding RNA MEG3 have been independently reported to be tumor suppressor genes in various cancers. However, their expression has never been previously associated with gastric cancer (GC)., Aims: To investigate the interaction of miR-141 and MEG3 in GC., Methods: QRT-PCR was used to detect miR-141, MEG3, and E2F3 in gastric tissues and cells. CCK-8 and flow cytometry analysis were used to detect cell functions. Western blot and luciferase activity were used to identify E2F3 as one of the direct targets of miR-141., Results: We found that expression of both miR-141 and MEG3 was significantly reduced in GC compared with levels in matched nonmalignant tissues. Positive correlation between miR-141 and MEG3 was found in both tumor tissues and control tissues. Furthermore, the over-expression of either miR-141 or MEG3 in 7901 and MKN45 cells inhibited cell proliferation and cell cycle progression and promoted cell apoptosis. E2F3 was identified as a target of miR-141, and its inhibition significantly reduced MEG3 expression. E2F3 expression was also found to be negatively associated with both MEG3 and miR-141. E2F3 over-expression partly reversed the changes caused by transfection of miR-141 mimic, and inhibition of miR-141 or MEG3 overrides MEG3- or miR-141-induced modulation of cell growth in GC., Conclusions: These findings together suggested that miR-141 could be interacting with MEG3 and targeting E2F3, and these factors may play important anti-tumor effects in GC pathogenesis and provide therapeutic targets in the clinics.

HOTAIR is a long non-coding RNA that interacts with the polycomb repressive complex and suppresses its target genes. HOTAIR has also been demonstrated to promote malignancy. MicroRNA-141 (miR-141) has been reported to play a role in the epithelial to mesenchymal transition process, and the expression of miR-141 is inversely correlated with tumorigenicity and invasiveness in several human cancers. We found that HOTAIR expression is inversely correlated to miR-141 expression in renal carcinoma cells. HOTAIR promotes malignancy, including proliferation and invasion, whereas miR-141 suppresses malignancy in human cancer cells. miR-141 binds to HOTAIR in a sequence-specific manner and suppresses HOTAIR expression and functions, including proliferation and invasion. Both HOTAIR and miR-141 were associated with the immunoprecipitated Ago2 (Argonaute2) complex, and the Ago2 complex cleaved HOTAIR in the presence of miR-141. These results demonstrate that HOTAIR is suppressed by miR-141 in an Ago2-dependent manner.

Abstract Introduction MicroRNAs (miRNAs) are single RNA molecules that act as global regulators of gene expression in mammalian cells and thus constitute attractive targets in treating cancer. Here we aimed to investigate the possible involvement of miRNA-141 (miR-141) in cervical cancer and to identify its potential targets in cervical cancer cell lines. Methods The level of miR-141 in HeLa and C-33A cells has been assessed using the quantitative real-time PCR (qRT-PCR). A new miR-141 construct has been performed in a CMV promoter vector tagged with GFP. Using microarray analysis, we identified the potentially regulated genes by miR-141 in transfected HeLa cells. The protein profile of killer-like receptor C1 (KLRC1), KLRC3, carcinoembryonic antigen‐related cell adhesion molecule 3 (CAM3), and CAM6 was investigated in HeLa cells transfected with either an inhibitor, antagonist miR-141, or miR-141 overexpression vector using immunoblotting and flow cytometry assay. Finally, ELISA assay has been used to monitor the produced cytokines from transfected HeLa cells. Results The expression of miR-141 significantly increased in HeLa and C-33A cells compared to the normal cervical HCK1T cell line. Transfection of HeLa cells with an inhibitor, antagonist miR-141, showed a potent effect on cancer cell viability, unlike the transfection of miR-141 overexpression vector. The microarray data of HeLa cells overexpressed miR-141 provided a hundred of downregulated genes, including KLRC1, KLRC3, CAM3, and CAM6. KLRC1 and KLRC3 expression profiles markedly depleted in HeLa cells transfected with miR-141 overexpression accompanied by decreasing interleukin 8 (IL-8), indicating the role of miR-141 in avoiding programmed cells death in HeLa cells. Likewise, CAM3 and CAM6 expression reduced markedly in miR-141 transduced cells accompanied by an increasing level of transforming growth factor beta (TGF-β), indicating the impact of miR-141 in cancer cell migration. The IntaRNA program and miRWalk were used to check the direct interaction and potential binding sites between miR-141 and identified genes. Based on this, the seeding regions of each potential target was cloned upstream of the luciferase reporter gene in the pGL3 control vector. Interestingly, the luciferase activities of constructed vectors were significantly decreased in HeLa cells pre-transfected with miR-141 overexpression vector, while increasing enormously in cells pre-transfected with miR-141 specific inhibitor. Conclusion Together, these data uncover an efficient miR-141-based mechanism that supports cervical cancer progression and identifies miR-141 as a credible therapeutic target.

Lung adenocarcinoma, the most prevalent lung cancer subtype, is characterized by its high propensity to metastasize. Despite the importance of metastasis in lung cancer mortality, its underlying cellular and molecular mechanisms remain largely elusive. Here, we identified miR-200 miRNAs as potent suppressors for lung adenocarcinoma metastasis. miR-200 expression is specifically repressed in mouse metastatic lung adenocarcinomas, and miR-200 decrease strongly correlates with poor patient survival. Consistently, deletion of mir-200c/141 in the KrasLSL-G12D/+ ; Trp53flox/flox lung adenocarcinoma mouse model significantly promoted metastasis, generating a desmoplastic tumor stroma highly reminiscent of metastatic human lung cancer. miR-200 deficiency in lung cancer cells promotes the proliferation and activation of adjacent cancer-associated fibroblasts (CAFs), which in turn elevates the metastatic potential of cancer cells. miR-200 regulates the functional interaction between cancer cells and CAFs, at least in part, by targeting Notch ligand Jagged1 and Jagged2 in cancer cells and inducing Notch activation in adjacent CAFs. Hence, the interaction between cancer cells and CAFs constitutes an essential mechanism to promote metastatic potential.

Simple Summary: T-prolymphocytic leukemia (T-PLL) is a rare and poor-prognostic mature T-cell leukemia. A better understanding of this chemotherapy-refractory disease is highly warranted to identify novel treatment strategies. We previously identified an elevated expression of the miR-141/200c cluster in T-PLL cells. Here, we show a pro-proliferative effect of miR-141/200c in mature T-cell lymphoma cell lines. We further characterize a miR-141/200c-driven transcriptome, entailing altered expression of genes involved in pathways regulating cell survival and differentiation. Among those, we identified STAT4 as a miR-141/200c target gene, with low STAT4 expression being associated with an immature phenotype of T-PLL cells and with shortened overall survival of T-PLL patients. Overall, we present an oncogenic miR-141/200c-STAT4 signaling route in T-PLL, demonstrating, for the first time, a role of non-protein-coding genes in the leukemogenesis of this devastating disease. T-prolymphocytic leukemia (T-PLL) is a rare and mature T-cell malignancy with characteristic chemotherapy-refractory behavior and a poor prognosis. Molecular concepts of disease development have been restricted to protein-coding genes. Recent global microRNA (miR) expression profiles revealed miR-141-3p and miR-200c-3p (miR-141/200c) as two of the highest differentially expressed miRs in T-PLL cells versus healthy donor-derived T cells. Furthermore, miR-141/200c expression separates T-PLL cases into two subgroups with high and low expression, respectively. Evaluating the potential pro-oncogenic function of miR-141/200c deregulation, we discovered accelerated proliferation and reduced stress-induced cell death induction upon stable miR-141/200c overexpression in mature T-cell leukemia/lymphoma lines. We further characterized a miR-141/200c-specific transcriptome involving the altered expression of genes associated with enhanced cell cycle transition, impaired DNA damage responses, and augmented survival signaling pathways. Among those genes, we identified STAT4 as a potential miR-141/200c target. Low STAT4 expression (in the absence of miR-141/200c upregulation) was associated with an immature phenotype of primary T-PLL cells as well as with a shortened overall survival of T-PLL patients. Overall, we demonstrate an aberrant miR-141/200c-STAT4 axis, showing for the first time the potential pathogenetic implications of a miR cluster, as well as of STAT4, in the leukemogenesis of this orphan disease. [ABSTRACT FROM AUTHOR]

Background: Cervical and lumbar pain is usually caused by degeneration of the nucleus pulposus (NP). As a powerful therapeutic strategy, tissue engineering can effectively restore the normal biological properties of the spinal unit. Previous studies suggested that poly(lactic-co-glycolic acid) (PLGA) microspheres are effective carriers of cells and biomolecules in NP tissue engineering. This study aims to explore the therapeutic effect of PLGA microspheres coloaded with transforming growth factor-β1 (TGF-β1) and anti-miR-141 on intervertebral disc degeneration (IDD). Methods: PLGA microspheres were characterized by scanning electron microscopy, a laser particle size analyzer, and laser confocal microscopy. The in vitro release rate of biomolecules from the microspheres was analyzed by reversed-phase high-performance liquid chromatography and agarose gel electrophoresis. The rat NP cells (NPCs) treated with the solutions released from microspheres for different lengths of time were assigned to a control group (Ctrl), an empty PLGA microsphere group (Mock microsphere, MS), a TGF-β1-loaded PLGA microsphere group (TMS), an anti-miR-141-loaded PLGA microsphere group (AMS), and an anti-miR-141 + TGF-β1-loaded PLGA microsphere group (ATMS). The proliferation and apoptosis of NPCs were observed by alamar blue and flow cytometry. The gene and protein expression of cartilage markers COL2A1 and ACAN were observed by RT-qPCR and Western blot. The rat model of IDD was established by tail puncture. Rats were divided into a control group (Ctrl), a mock operation group (Mock), a TGF-β1 microsphere group (TMS), an anti-miR-141 microsphere group (AMS), and an anti-miR-141 + TGF-β1 microsphere group (ATMS). The degree of rat tail IDD was assessed in each group through magnetic resonance imaging (MRI), safranin O-fast green staining, immunohistochemistry, and Western blotting. Results: PLGA microspheres were stably coloaded and could sustainably release TGF-β1 and anti-miR-141. The results of in vitro cell experiments showed that the release solution of PLGA microspheres significantly enhanced the proliferation of NPCs without inducing their apoptosis and significantly upregulated cartilage markers in NPCs. The effect of microspheres was greater in the ATMS group than that in the TMS group and AMS group. In vivo experiments showed that IDD could be effectively inhibited and reversed by adding microspheres coloaded with TGF-β1 and/or anti-miR-141, and the effect was greatest in the ATMS group. Conclusion: PLGA microspheres coloaded with TGF-β1 and anti-miR-141 can reverse IDD by inhibiting the degeneration of NPCs. [ABSTRACT FROM AUTHOR]

Osteosarcoma (OS) is one of the most common types of malignant tumors characterized by uncontrolled proliferation ability and acquired drug resistance. The previous study indicated that lncRNA KRAL participated in the reversal of 5-FU resistance in liver cancer, but it remains unclear whether lncRNA KRAL involved in doxorubicin (DOX) resistance of osteosarcoma. The expression of lncRNA KRAL and MicroRNAs-141 (miR-141) were detected by RT-qPCR experiment. Also, we used the plasmids transfection to construct the lncRNA KRAL overexpressed OS cell lines. Subsequently, the cell proliferation ability and the sensitivity to DOX in OS cells upon upregulating lncRNA KRAL expression were analyzed via CCK-8 and EDU assay, while western blotting experiment was performed to detect the regulatory mechanism. We found that lncRNA KRAL was downregulated in OS tissues, and the OS patients with OS patients with lower expression of lncRNA KRAL were more likely to have advanced Enneking stage, larger tumor size and distant metastasis. Subsequently, we discovered that upregulation of lncRNA KRAL could inhibit cell proliferation and increase the sensitivity to DOX of OS cells. Interestingly, the western blot results showed that over-expression of lncRNA KRAL could lead to down-expression of P-gp protein and reversal of Epithelial–mesenchymal transition (EMT) pathway. Furthermore, we identified miR-141 as the downstream target gene of lncRNA KRAL, which was further confirmed by the luciferase reporter assay. More importantly, our data demonstrated that addition of miR-141 could reverse cell proliferation and drug sensitivity of lncRNA KRAL-overexpressed OS cells. LncRNA KRAL could suppress cell growth and increases sensitivity to DOX in OS cells by sponging miR-141. [ABSTRACT FROM AUTHOR]

Purpose: Recent studies have demonstrated the differential expression of micro(mi)RNAs in endometriosis. Previously, we reported the low expression of miR-141 in patients with this disease. Epithelial-to-mesenchymal transition (EMT) and the transforming growth factor-beta1 (TGF-β1)-induced SMAD2 signalling pathway are central to tumour proliferation and invasion. However, the role of miR-141 in regulating the TGF-β1/SMAD2 signalling pathway and the associated EMT to be elucidated.Methods: The levels of TGF-β1/SMAD2 signalling and EMT markers expression in eutopic and ectopic endometria of endometriosis were determined by immunohistochemistry and western blot analyses. MiR-141 expression was analysed by quantitative reverse-transcription polymerase chain reaction. Cellular invasion and proliferation were determined by transwell and CCK-8 assays, respectively. Functional assay of miR-141 was performed using plasmid and shRNA transfection methods.Result: The presence of miR-141, EMT, and TGF-β1/SMAD2 signalling markers were detected in eutopic and ectopic endometria of endometriosis. TGF-β1-induced EMT in Ishikawa (ISK) cells by activating the SMAD2 signalling pathway, whereas miR-141 inhibited the TGF-β1-induced EMT, proliferation and invasion abilities of these cells.Conclusion: These data identify miR-141 as a novel driver of EMT in endometriosis, implicates the link between miR-141 and TGF-β1/SMAD2 signalling pathway in the context of endometriosis, and underscore the role of EMT in the development of endometriosis. [ABSTRACT FROM AUTHOR]

Objective: To study the significance of mir-141 expression in COPD (chronic obstructive pulmonary diseases) mononuclear cells, and to demonstrate its effect on proliferation and apoptosis of fibroblasts Possible to ZEB1(zinc finger E-box binding homeobox 1). Methods: 40 cases acute phase of COPD patients, 80 cases of stable period COPD patients and 110 normal controls in our hospital were collected. RT-PCR was used to detect mir-141 and statistical analysis. The mir-141 mimic was constructed and transfected into lung fibroblasts. The expression of mir-141 was analyzed by RT-PCR. Cell proliferation was analyzed by CCK8 and cell apoptosis was detected by flow cytometry. Targetscan was used to predict the binding site of ZEB1 and mir-141. The target relationship between ZEB1 and mir-141 was identified by RT-PCR and western blot. Results: The expression of mir-141 in mononuclear cells of acute phase of COPD and stable period of COPD was significantly higher than that of normal controls. Mir-141 levels in acute phase of COPD were significantly higher than that of stable period of COPD. Mir-141 mimic transfection significantly up-regulated the expression of mir- 141, promoted cell activity and decreased cell apoptosis rate compared with the empty control group. ZEB1 and mir-141 had binding sites predicted by Targetscan database and verified by dual luciferase assays. After mir-141 mimic transfection hat, ZEB1 mRNA and protein expression were down-regulated. Conclusions: High expression of mir-141 in COPD may promote the proliferation of lung fibroblasts and inhibit apoptosis by targeting ZEB1. [ABSTRACT FROM AUTHOR]

Glioblastoma is the most aggressive brain tumor. Although miR-141 has been demonstrated to primarily function as a tumor suppressor in numerous malignancies, including glioblastoma, the mechanisms involved remain poorly understood. Here, it is shown that miR-141 is downregulated in glioblastoma cell lines and tissues and may exert its biological function via directly targeting myelin transcription factor 1-like (MYT1L). Using two glioblastoma cell lines that differ from each other by the functionality of DNA-dependent protein kinase (DNAPK), a functional involvement of DNAPK in the miR-141 tumor suppression network was observed. In M059K cells with a normal function of DNAPK, the enforced expression of miR-141 attenuated MYT1L expression and suppressed cell proliferation. Conversely, the inhibition of miR-141 expression promoted cell proliferation; however, in M059J cells with a loss-of-function DNAPK, miR-141 constitutively inhibited cell proliferation upon ectopic overexpression or inhibition. An overexpression of miR-141 suppressed M059J cell migration, while it had no effect on M059K. Furthermore, the ectopic expression of miR-141 induced an S-phase arrest in both cell lines, whereas the inhibition of miR-141 caused a G1 arrest in M059J and accelerated the S phase in M059K. An overexpression and suppression of miR-141 resulted in an aberrant expression of cell-cycle proteins, including p21. Moreover, MYT1L may be a transcription factor of p21 in p53-mutant cells, whereas DNAPK may function as a repressor of MYT1L. The findings revealed the crucial role of DNAPK in miR-141-mediated suppression of gliomagenesis and demonstrated that it may be a target molecule in miR-141-associated therapeutic interventions for glioblastoma. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is a chronic inflammation mediated by autoimmune responses. MEG3, a kind of long noncoding RNA (lncRNA), participates in cell proliferation in cancer tissues. However, the correlation between MEG3 and RA is yet unclear. Therefore, to clarify how MEG3 works in RA, we performed a series of experiments using RA samples. We found that MEG3 was downregulated in the fibroblast‐like synoviocytes of RA patients (RA‐FLS), in comparison with healthy subjects. MEG3 was also down‐regulated evidently in lipopolysaccharide (LPS)‐treated chondrocyte. As part of our experiments, MEG3 was overexpressed in chondrocyte by transfection with lentivirus containing sequences encoding MEG3. In addition, in presence of LPS, reductions were identified not only in the cell proliferation, but also in the generation of interleukin‐23 (IL‐23), which, however were reversed in the lentivirus (containing MEG3‐encoding sequences)‐transfected chondrocytes. Up‐regulated MEG3 resulted in an increase the level of Ki67. Moreover, MEG3 was negatively correlated with miR‐141, and miR‐141 was up‐regulated in LPS‐treated chondrocyte. Inhibitory effects of MEG3 overexpression, mentioned above, were partially abolished by overexpressed miR‐141. Further, animal experiment also showed the inhibitory effect of MEG3 in overexpression on the AKT/mTOR signaling pathway. In‐vivoexperiments also showed that cell proliferation was facilitated by MEG3 overexpression with inhibited inflammation. In summary, the protective role of MEG3 in RA was proved to be exerted by the increase in the rate of proliferation, which might correlate to the regulatory role of miR‐141 and AKT/mTOR signal pathway, suggesting that MEG3 holds great promise as a therapeutic strategy for RA. [ABSTRACT FROM AUTHOR]

Background: The long noncoding RNA X-inactive specific transcript (XIST) was reported to play vital roles in tumor progression. In the present study, we determined the regulatory function of XIST in papillary thyroid carcinoma (PTC).Materials and methods: XIST expression was determined in PTC tissues and cell lines by quantitative real-time polymerase chain reaction (PCR) (qRT-PCR). Cellular proliferation, migration, and invasion were measured using the Cell Counting Kit-8 (CCK-8) assay, wound-healing assay, and transwell invasion assay, respectively. Western blotting was used to determine protein expression. The downstream target miRNAs for XIST were identified by luciferase reporter assay and qRT-PCR.Results: Relative expression of XIST was upregulated in PTC tissues and cell lines. High XIST expression was positively correlated with TNM stage and lymph node metastasis. Function assay demonstrated that knockdown of XIST significantly decreased cell proliferation, migration, and invasion in PTC cells. Moreover, we showed that the effects of XIST on PTC cell progression were mediated by miR-141.Conclusion: Our results demonstrated that XIST functioned as an oncogene in PTC progression by regulating miR-141, suggesting that XIST might be a promising therapeutic target for PTC treatment. [ABSTRACT FROM AUTHOR]

Introduction: Abnormal expression of microRNAs (miRNAs) contributes to cancer development through regulating proliferation, apoptosis and drug resistance in cancer cells. The present study was designed to explore the effect and mechanism of miR-141 on gastric cardia adenocarcinoma (GCA). Material and methods: Forty-one paired GCA tissues and adjacent normal tissues were obtained from GCA patients never treated by chemotherapy or radiotherapy. QRT-PCR was used to detect the expression level of miR-141 in GCA. Effects of miR-141 on cell proliferation and apoptosis were detected in vitro. Western blot analysis was used to determine the downstream targets of miR-141. Results: In the present study, our data showed that miR-141 was significantly decreased and correlated with advanced TNM stage and lymph node metastases in GCA. In addition, we found that miR-141 could inhibit cell proliferation and induce cell apoptosis in AGS cells. Moreover, MACC1 was predicted as a possible target of miR-141. The luciferase reporter assay proved that miR-141 could suppress MACC1 directly by binding to its 3'-UTR. Further studies showed that miR-141 influenced the MEK/ERK and p38 MAPK signaling pathways. Conclusions: Our findings demonstrated that miR-141 expression was associated with GCA progression. MACC1, working as one possible target of miR-141, may contribute to the process. MiR-141 is expected to be a potential therapeutic target for the treatment of GCA patients. [ABSTRACT FROM AUTHOR]

Background: LncRNA small nucleolar RNA host gene 15 (SNHG15) was reported to play an oncogenic role in tumors. However, the role of SNHG15 and its molecular mechanism in osteosarcoma (OS) cells are largely unknown. Methods: qRT-PCR was performed to evaluate the expression levels of SNHG15 and miR-141 in OS tissues and cells. Cell transfection with different siRNAs, miRNAs or pcDNAs into U2OS and MG63 cells were carried out by Lipofectamine 2000. The effects of SNHG15 and miR-141 on OS cell proliferation, invasion and the levels of autophagy-related proteins were analyzed by MTT assay, Transwell invasion/migration assay and western blot, respectively. Luciferase reporter assay was used to confirm whether SNHG15 could directly interact with miR-141. Results: We found that up-regulation of SNHG15 was inversely correlated with miR-141 expression in OS tissues. SNHG15 knockdown and miR-141 overexpression significantly suppressed cell proliferation, invasion, migration and autophagy while SNHG15 overexpression and miR-141 repression exhibited the opposite effects on OS cells. Besides, SNHG15 could directly interact with miR-141 and regulate its expression. Furthermore, miR-141 suppressing significantly overturned the inhibition on proliferation, invasion, migration and autophagy mediated by SNHG15 knockdown while miR-141 overexpression remarkably attenuated SNHG15 overexpression-induced proliferation, invasion, migration and autophagy in OS cells. Conclusion: Our data showed that SNHG15 contributes to proliferation, invasion, migration and autophagy in OS by negatively regulating miR-141, providing a new potential target and prognostic biomarker for the treatment of OS. [ABSTRACT FROM AUTHOR]

Background: The aberrant expression of sperm-associated antigen 9 (SPAG9) is associated with numerous cancers, including hepatocellular carcinoma (HCC). The exploration of molecules and mechanisms regulating SPAG9 expression may provide new options for HCC therapy. Methods: MiRNA target prediction programs were used to explore SPAG9-targeted miRNAs. SPAG9 and miR-141 expression were detected in HCC tissues and cell lines by Western blot and real-time PCR. Dual-luciferase reporter assay was utilized to validate SPAG9 as a direct target gene of miR-141. Cell proliferation, invasion, and migration assays were used to determine whether miR-141-mediated regulation of SPAG9 could affect HCC progression. Results: An inverse correlation was observed between SPAG9 and miR-141 expression in HCC tissues and cell lines. Dual-luciferase reporter assay further showed that SPAG9 was a direct target gene of miR-141. The ectopic expression of miR-141 could markedly suppress SPAG9 expression in HCC cells. MiR-141 overexpression also resulted in significantly reduced cell proliferation, invasion, and migration, and imitation of the SPAG9 knockdown effects on HCC cells. Furthermore, SPAG9 restoration in miR-141-expressing cells sufficiently attenuated the tumor-suppressive effects of miR-141. Finally, JNK activity was found to be reduced by miR-141 overexpression the same way as by SPAG9 silencing. The overexpression of SPAG9 lacking its 3'-UTR significantly restored JNK activity and its downstream genes in miR-141-transfected HCC cells. Conclusion: MiR-141 suppression may cause aberrant expression of SPAG9 and promote HCC tumorigenesis via JNK pathway. [ABSTRACT FROM AUTHOR]

Human microRNA-141 (miR-141), a member of the miR-200 family, has been reported to be associated with various human malignancies. However, it remains unknown whether miR-141 is involved in the pathogenesis of gastric cancer. Therefore, we examined the expression of miR-141 in gastric cancer tissues and the effect of miR-141 overexpression on cancer cell proliferation. The expression level of miR-141 in 35 pair-matched gastric neoplastic and adjacent non-neoplastic tissues, and in 5 gastric cancer cell lines were examined by quantitative real-time PCR. The growth of MGC-803 cells transfected with miRNA precursor was examined by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazoliumbromide) assay. MiR-141 was significantly down-regulated in 80% (28/35) of primary gastric cancer tissues compared with pair-matched adjacent non-tumor tissues ( P < 0.01). The expression of miR-141 was also found to be substantially reduced in several human gastric cancer cell lines such as MGC-803, HGC-27, SGC-7901 and BGC-823 cells. Overexpression of miR-141 with its precursors significantly inhibited the proliferation of gastric cancer cells. These results suggest that miR-141 may be involved in the development of gastric cancer through its inhibitory effect on cell proliferation. [ABSTRACT FROM AUTHOR]

Background: 5-Fluorouracil (5-FU) has been widely applied to treat various types of cancers, including hepatocellular carcinoma (HCC). However, primary or acquired 5-FU resistance prevents the clinical application of this drug in cancer therapy. Herein, our study is the first to demonstrate that lower expression of KRAL, a long non-coding RNA (lncRNA), mediates 5-FU resistance in HCC via the miR-141/Keap1 axis. Methods: Cell proliferation assays, western blot analysis, qRT-PCR, the dual-luciferase reporter assay and RNA immunoprecipitation were performed to investigate the mechanisms by which KRAL mediates 5-fluorouracil resistance in HCC cell lines. Results: The quantitative analysis indicated that KRAL and Keap1 were significantly decreased and that Nrf2 was increased in HepG2/5-FU and SMMC-7721/5-FU cells compared with the corresponding expression levels in the respective parental cells. Overexpression of KRAL increased Keap1 expression, and inactivating the Nrf2-dependent antioxidant pathway could reverse the resistance of HepG2/5-FU and SMMC-7721/5-FU cells to 5-FU. Moreover, KRAL functioned as a competitive endogenous RNA (ceRNA) by effectively binding to the common miR-141 and then restoring Keap1 expression. These findings demonstrated that KRAL is an important regulator of Keap1; furthermore, the ceRNA network involving KRAL may serve as a treatment strategy against 5-FU resistance in hepatocellular carcinoma cells. Conclusions: KRAL/miR-141/Keap1 axis mediates 5-fluorouracil resistance in HCC cell lines. [ABSTRACT FROM AUTHOR]