Background: MicroRNAs (miRNAs) have been suggested to play a vital role in tumor initiation and progression by negatively regulating oncogenes and tumor suppressors. Quite recently, studies have identified some miRNAs operating to promote or suppress tumor invasion or metastasis via regulating metastasis-related genes, providing potential therapeutic targets on anti-metastasis strategy. Metastasis-associated in colon cancer-1 (MACC1) has been newly identified to express highly in colorectal cancer (CRC) and promote tumor metastasis through transactivating metastasis-inducing HGF/MET signaling pathway. In this study, we investigated whether miRNA 143 is involved in the regulation of MACC1 and thus plays a functional role in CRC. Results: Using both in silico prediction and western blot assay, we found the previously reported tumor suppressive miR-143 targeted MACC1 in CRC. The direct interaction between them was confirmed by 3' UTR luciferase reporter gene. In concordance with the inhibitory effects induced by siRNA mediated knockdown of MACC1, restoration of miR-143 by mimics in SW620 cells significantly attenuated cell growth, migration and invasion. It is notable that combined treatment of miR-143 mimics and MACC1 siRNA induced synergistic inhibitory effects compared to either miR-143 mimics or MACC1 siRNA treatment alone. Conversely, reduction of miR-143 by inhibitors in SW480 cells apparently stimulated these phenotypes. Furthermore, we observed that miR-143 level was inversely correlated with MACC1 mRNA expression in CRC tissues. Conclusions: Our findings newly described miR-143/MACC1 link and provided a potential mechanism for MACC1 dysregulation and contribution to CRC cell invasion. It may help to estimate the therapeutic utility of miR-143 in CRC.
28 August 2019 in Journal of Experimental & Clinical Cancer Research
Accumulating evidence demonstrates the oncogenic roles of lncRNA (long non-coding RNA) molecules in a wide variety of cancer types including glioma. Equally important, However, tumorigenic functions of lncRNA in glioma remain largely unclear. A recent study suggested lncRNA SNHG15 played a role for regulating angiogenesis in glioma but its role in the tumor microenvironment (TME) was not investigated. First, we showed that SNHG15 was upregulated in GBM cells and associated with a poor prognosis for the patients of GBM using public databases. Next, we collected temozolomide sensitive (TMZ-S) and resistant (TMZ-R) clinical samples and demonstrated that co-culturing TMZ-R cells with HMC3 (microglial) cells promoted M2-polarization of HMC3 and the secretion of pro-GBM cytokines TGF-β and IL-6. Comparative qPCR analysis of TMZ-S and TMZ-R cells showed that a significantly higher level of SNHG15, coincidental with a higher level of Sox2, β-catenin, EGFR, and CDK6 in TMZ-R cells. Subsequently, using bioinformatics tool, a potential mechanistic route for SNHG15 to promote GBM tumorigenesis was by inhibiting tumor suppressor, miR-627-5p which leads to activation of CDK6. Gene-silencing technique was employed to demonstrate that suppression of SNHG15 indeed led to the suppression of GBM tumorigenesis, accompanied by an increase miR-627-5p and decreased its two oncogenic targets, CDK6 and SOX-2. In addition, SNHG15-silenced TMZ-R cells became significantly sensitive towards TMZ treatment and less capable of promoting M2-phenotype in the HMC3 microglial cells. We then evaluated the potential anti-GBM activity of CDK6 inhibitor, palbociclib, using TMZ-R PDX mouse models. Palbociclib treatment significantly reduced tumorigenesis in TMZ-R/HMC3 bearing mice and SNHG15 and CDK6 expression was significantly reduced while miR-627-5p level was increased. Additionally, palbociclib treatment appeared to overcome TMZ resistance as well as reduced M2 markers in HMC3 cells. Together, we provided evidence supporting the usage of CDK6 inhibitor for TMZ-resistant GBM cases. Further investigation is warranted for the consideration of clinical trials.
Accumulating evidence indicates long noncoding RNAs (lncRNA) play a vital role in tumor progression. However, the role of linc00645-induced accelerated malignant behavior in glioblastoma (GBM) remains unknown. In the present study, linc00645 expression was significantly upregulated in GBM tissues and cell lines. High level of linc00645 was associated with poor overall survival in GBM patients. Knockdown of linc00645 suppressed the proliferation, stemness, migration, invasion, and reversed transforming growth factor (TGF)-β-induced motility of glioma cell lines. Furthermore, linc00645 directly interacted with miR-205-3p and upregulated of miR-205-3p impeded efficiently the increase of ZEB1 induced by linc00645 overexpression. Moreover, knockdown of linc00645 significantly suppressed the progression of glioma cells in vivo. miR-205-3p was a target of linc00645 and linc00645 modulates TGF-β-induced glioma cell migration and invasion via miR-205-3p. Taken together, our findings identified the linc00645/miR-205-3p/ZEB1 signaling axis as a key player in EMT of glioma cells triggered by TGF-β. These data elucidated that linc00645 plays an oncogenic role in glioma and it may serve as a prognostic biomarker and a potential therapeutic target for the treatment of glioma in humans.
Background: To assess the causal role of lipid traits and lipid-lowering agents in inflammatory bowel disease (IBD).Methods: Univariable mendelian randomization (MR) and multivariable MR (MVMR) analyses were conducted to evaluate the causal association between low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C) and IBD. Drug-targeted MR analyzed the effects of lipid-lowering drugs on IBD, and network MR was used to analyze potential mediation effects.Results: The levels of HDL-C had an inverse relationship with the risk of Crohn’s disease (CD, OR: 0.85, 95% CI: 0.73-0.98, P = 0.024). In MVMR, the inverse relationships were found in all three outcomes. Drug-targeted MR analyses showed that with one-SD LDL-C decrease predicted by variants at or near proprotein convertase subtilisin/kexin type 9 (PCSK9), the OR values of people diagnosed with IBD, ulcerative colitis (UC) and CD were 1.75 (95%CI: 1.13-2.69, P = 0.011), 2.1 (95%CI: 1.28-3.42, P = 0.003) and 2.24 (95%CI: 1.11-4.5, P = 0.024), respectively. With one-SD LDL-C decrease predicted by variants at or near cholesteryl ester transfer protein (CETP), the OR value of people diagnosed with CD was 0.12 (95%CI: 0.03-0.51, P = 0.004). Network-MR showed that HDL-C mediated the causal pathway from variants at or near CETP to CD.Conclusion: Our study suggested a causal association between HDL-C and IBD, UC and CD. Genetically proxied inhibition of PCSK9 increased the risk of IBD, UC and CD, while inhibition of CETP decreased the risk of CD. Further studies are needed to clarify the long-term effect of lipid-lowering drugs on the gastrointestinal disorders.
The morbidity of NASH has increased, with limited effective treatment options. IL-17 plays a protective role in the gut mucosa in high-fat-diet (HFD)-related metabolic disorders, and HFD-related microbiota dysbiosis is responsible for a decreased number of T helper 17 (T H 17) cells in the lamina propria.