MicroRNA-374a suppresses colon cancer progression by directly reducing CCND1 to inactivate the PI3K/AKT pathway.
ABSTRACT: microRNA-374a (miR-374a) exhibits oncogenic functions in various tumor types. Here we report that miR-374a suppresses proliferation, invasion, migration and intrahepatic metastasis in colon adenocarcinoma cell lines HCT116 and SW620. Notably, we detected that PI3K/AKT signaling and its downstream cell cycle factors including c-Myc, cyclin D1 (CCND1), CDK4 and epithelial-mesenchymal transition (EMT)-related genes including ZEB1, N-cadherin, Vimentin, Slug, and Snail were all significantly downregulated after miR-374a overexpression. Conversely, cell cycle inhibitors p21 and p27 were upregulated. Expression of E-cadherin was only decreased in HCT116, without any obvious differences observed in SW620 cells. Furthermore, luciferase reporter assays confirmed that miR-374a could directly reduce CCND1. Interestingly, when CCND1 was silenced or overexpressed, levels of pPI3K, pAkt as well as cell cycle and EMT genes were respectively downregulated or upregulated. We examined miR-374a levels by in situ hybridization and its correlation with CCND1 expression in CRC tumor tissues. High miR-374a expression with low level of CCND1 was protective factor in CRC. Together these findings indicate that miR-374a inactivates the PI3K/AKT axis by inhibiting CCND1, suppressing of colon cancer progression.
Project description:Our previous study has demonstrated that knockdown of Grainyhead-like 2(GRHL2) in colorectal cancer (CRC) cells inhibited cell proliferation by targeting ZEB1. This study aimed at researching whether knockdown of GRHL2 promoted CRC progression and metastasis via inducing epithelial-mesenchymal transition (EMT). GRHL2-upregulated SW-620/GRHL2+ and GRHL2-knockdown HCT116/GRHL2-KD, HT29/GRHL2-KD cells and their control cells were generated. The morphological changes after overexpression and knockdown GRHL2 were observed. qRT-PCR, Western blotting, and Immunofluorescence were used to detect EMT markers: E-cadherin, Vimentin, p-catein, ZO-1 and ZEB1 expression. Then, sh-ZEB1 was transfected to GRHL2 knockdown cells to research the relationship between GRHL2 and ZEB1. Transwell and wound healing assays were further performed to detect the impact of GRHL2 on invasion and migration in vitro. CRC cells were injected into mice tail vein to verify the impact of GRHL2 on CRC metastasis. Morphological change of mesenchymal-epithelial transition (MET) could be observed in SW620/GRHL2+ cell. The expression of epithelial markers: E-cadherin, ?-catenin, ZO-1 were up-regulated, while mesenchymal markers: Vimentin was decreased. Meanwhile, opposite EMT morphological change could be observed in HCT116/GRHL2-KD cell, accompanied by reverse change of E-cadherin, ?-catenin, ZO-1, and Vimentin. The expression level of GRHL2 and ZEB1 was found negative in both SW620/GRHL2+ and HCT116/GRHL2-KD cells. Knockdown of ZEB1 by siRNA in HCT116/GRHL2-KD and HT29/GRHL2-KD could upregulate expression of E-cadherin and GRHL2. GRHL2 knockdown also promoted migration, invasion in vitro and CRC metastasis in mice model. In conclusion, GRHL2/ZEB1 axis inhibits CRC progression and metastasis via oppressing EMT.
Project description:BACKGROUND:MicroRNA-196a-5p (miR-196a-5p) has been reported to be involved in the metastatic process of several cancers. In present work, we aimed to investigate the effects of miR-196a-5p and its potential target I?B? on migration, invasion and epithelial-mesenchymal transition (EMT) of colorectal cancer (CRC) cells. METHODS:CCK-8 assay, wound healing assay and cell invasion assay were performed to evaluate the cell proliferation, migration and invasion. In vivo metastasis models were used to investigate the tumor metastasis ability. Real-time PCR, immunofluorescence staining or western blot were utilized to detect the expression of miR-196a-5p, I?B?, p-I?B?, nuclear p65 and EMT markers including E-cadherin, N-cadherin and fibronectin. Dual luciferase reporter assay was carried out to determine whether there is a direct interaction between miR-196a-5p and I?B? mRNA. RESULTS:Using SW480 cell with miR-196-5p over-expressed plus SW620 and HCT116 cells with miR-196a-5p knockdown, we found that miR-196a-5p promoted cell proliferation, migration and invasion in vitro and facilitated liver metastasis in vivo. We also observed that miR-196a-5p knockdown or NF-?B pathway inhibition up-regulated E-cadherin while down-regulated N-cadherin and fibronectin. By contrast, miR-196a-5p over-expression promoted EMT process of CRC. Data of dual luciferase reporter assay indicated that miR-196a-5p targeted the I?B?. Moreover, miR-196a-5p down-regulated I?B? expression while up-regulated nuclear p65 expression. Additionally, over-expression of I?B? in CRC cells attenuated the effects of miR-196a-5p on cell migration, invasion and EMT. CONCLUSIONS:miR-196a-5p may play a key role in EMT, invasion and metastasis of CRC cells via targeting the I?B?.
Project description:MiR-374a appears to play a complex role in non-small-cell lung cancer (NSCLC). Here, we demonstrate a dual role for miR-374a in NSCLC pathogenesis. The effects and modulatory mechanisms of miR-374a on cell growth, migration, invasion, and in vivo tumorigenesis and metastasis in nude mice were also analyzed. The expression of miR-374a was examined in NSCLC and non-cancerous lung tissues by quantitative real-time reverse transcription-PCR (qRT-PCR), and in situ hybridization, respectively. miR-374a directly targets CCND1 and inactivates PI3K/AKT and Ras-mediated cell cycle signalings, as well as epithelial-mesenchymal transition (EMT). This not only dramatically suppressed cell growth, migration, invasion,and metastasis, but also elevated A549 and pc-9 NSCLC cell sensitivity to cisplatin (DDP) while increasing survival time of tumor-bearing mice. Interestingly, miR-374a serves an inverse function in SPCA-1 and H1975 NSCLC cells by directly targeting PTEN to activate Wnt/β-catenin and Ras signalings and its downstream cascade signals. Surprisingly, transcription factor c-Jun bound to the promoter region of human miR-374a and suppressed miR-374a in A549 and pc-9 cells while inducing it in SPCA-1 and H1975 cells. Increased levels of miR-374a appeared to serve a protective role by targeting CCND1 in early-stage NSCLC (Stages I and II). Inversely, increased miR-374a was an unfavorable factor when targeting PTEN in more advanced staged NSCLC patients. Our studies are the first to demonstrate that miR-374a plays divergent roles in NSCLC pathogenesis at different stages of the disease and implicate the potential application of miR-374a targeting for cancer therapy.
Project description:The circadian clock coordinates biological and physiological functions to day/night cycles. The perturbation of the circadian clock increases cancer risk and affects cancer progression. Here, we studied how BMAL1 knockdown (BMAL1-KD) by shRNA affects the epithelial-mesenchymal transition (EMT), a critical early event in the invasion and metastasis of colorectal carcinoma (CRC). In corresponding to a gene set enrichment analysis, which showed a significant enrichment of EMT and invasive signatures in BMAL1_high CRC patients as compared to BMAL1_low CRC patients, our results revealed that BMAL1 is implicated in keeping the epithelial-mesenchymal equilibrium of CRC cells and influences their capacity of adhesion, migration, invasion, and chemoresistance. Firstly, BMAL1-KD increased the expression of epithelial markers (E-cadherin, CK-20, and EpCAM) but decreased the expression of Twist and mesenchymal markers (N-cadherin and vimentin) in CRC cell lines. Finally, the molecular alterations after BMAL1-KD promoted mesenchymal-to-epithelial transition-like changes mostly appeared in two primary CRC cell lines (i.e., HCT116 and SW480) compared to the metastatic cell line SW620. As a consequence, migration/invasion and drug resistance capacities decreased in HCT116 and SW480 BMAL1-KD cells. Together, BMAL1-KD alerts the delicate equilibrium between epithelial and mesenchymal properties of CRC cell lines, which revealed the crucial role of BMAL1 in EMT-related CRC metastasis and chemoresistance.
Project description:The 5-year survival rate for colorectal cancer is approximately 55 % because of its invasion and metastasis. The epithelial-mesenchymal transition (EMT) is one of the well-defined processes during the invasion and distant metastasis of primary epithelial tumors. miR-429, a member of the miR-200 family of microRNAs, was previously shown to inhibit the expression of transcriptional repressors ZEB1/delta EF1 and SIP1/ZEB2, and regulate EMT. In this study, we showed that miR-429 was significantly downregulated in colorectal carcinoma (CRC) tissues and cell lines. We found that miR-429 inhibited the proliferation and growth of CRC cells in vitro and in vivo, suggesting that miR-429 could play a role in CRC tumorigenesis. We also showed that downregulation of miR-429 may contribute to carcinogenesis and the initiation of EMT of CRC by targeting Onecut2. Further researches indicated that miR-429 inhibited the cells migration and invasion and reversed TGF-β-induced EMT changes in SW620 and SW480 cells. miR-429 could reverse the change of EMT-related markers genes induced by TGF-β1, such as E-cadherin, CTNNA1, CTNNB1, TFN, CD44, MMP2, Vimentin, Slug, Snail, and ZEB2 by targeting Onecut2. Taken together, our data showed that transcript factor Onecut2 is involved in the EMT, migration and invasion of CRC cells; miR-429 inhibits the initiation of EMT and regulated expression of EMT-related markers by targeting Onecut2; and miR-429 or Onecut2 is the important therapy target for CRC.
Project description:Colorectal cancer (CRC) responds poorly to immuno-mediated cytotoxicity. Underexpression of corticotropin-releasing-hormone-receptor-2 (CRHR2) in CRC, promotes tumor survival, growth and Epithelial to Mesenchymal Transition (EMT), in vitro and in vivo. We explored the role of CRHR2 downregulation in CRC cell resistance to Fas/FasL-mediated apoptosis and the underlying molecular mechanism. CRC cell sensitivity to CH11-induced apoptosis was compared between Urocortin-2 (Ucn2)-stimulated parental and CRHR2-overexpressing CRC cell lines and targets of CRHR2/Ucn2 signaling were identified through in vitro and ex vivo analyses. Induced CRHR2/Ucn2 signaling in SW620 and DLD1 cells increased specifically their sensitivity to CH11-mediated apoptosis, via Fas mRNA and protein upregulation. CRC compared to control tissues had reduced Fas expression that was associated with lost CRHR2 mRNA, poor tumor differentiation and high risk for distant metastasis. YY1 silencing increased Fas promoter activity in SW620 and re-sensitized them to CH11-apoptosis, thus suggesting YY1 as a putative transcriptional repressor of Fas in CRC. An inverse correlation between Fas and YY1 expression was confirmed in CRC tissue arrays, while elevated YY1 mRNA was clinically relevant with advanced CRC grade and higher risk for distant metastasis. CRHR2/Ucn2 signaling downregulated specifically YY1 expression through miR-7 elevation, while miR-7 modulation in miR-7high SW620-CRHR2+ and miR-7low HCT116 cells, had opposite effects on YY1 and Fas expressions and cell sensitivity to CH11-killing. CRHR2/Ucn2 signaling is a negative regulator of CRC cell resistance to Fas/FasL-apoptosis via targeting the miR-7/YY1/Fas circuitry. CRHR2 restoration might prove effective in managing CRC response to immune-mediated apoptotic stimuli.
Project description:BACKGROUND:Colorectal cancer (CRC) is one of the causes of cancer-related death worldwide. The aim of our study was to disclose the expression pattern and underlying molecular mechanism of circular RNA TADA2A (circTADA2A) in CRC. METHODS:The levels of circTADA2A, transcriptional adaptor 2A (TADA2A), microRNA-374a-3p (miR-374a-3p) and Kruppel like factor 14 (KLF14) were determined by quantitative real-time polymerase chain reaction (qRT-PCR). Xenograft tumor assay was used to uncover the function of circTADA2A in vivo. The miRNA targets of circTADA2A were searched using circbank and starbase softwares, while DIANA TOOL was used to explore miR-374a-3p-mRNA interactions. Dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay were performed to validate the target relationship of circTADA2A/miR-374a-3p/KLF14 axis. Cell cycle and apoptosis were analyzed by flow cytometry. The glycolysis of CRC cells was determined by Seahorse XFe 96 Extracellular Flux Analyzer, Glucose Uptake Colorimetric Assay kit, Lactate Assay Kit II and ATP Colorimetric Assay kit. KLF14 protein level was measured by Western blot assay. RESULTS:CircTADA2A was abnormally down-regulated in CRC tissues and cell lines. CircTADA2A overexpression impeded CRC tumor growth in vivo. MiR-374a-3p was verified as a target of circTADA2A in CRC cells, and circTADA2A inhibited the malignant potential of CRC cells through targeting miR-374a-3p. MiR-374a-3p interacted with KLF14 messenger RNA (mRNA), and miR-374a-3p deteriorated CRC through down-regulating KLF14. CircTADA2A enhanced the abundance of KLF14 through targeting miR-374a-3p in CRC cells. CONCLUSION:CircTADA2A functioned as a tumor suppressor in CRC to inhibit the glycolysis and cell cycle and potentiate the apoptosis of CRC cells via miR-374a-3p/KLF14 axis.
Project description:BACKGROUND AND PURPOSE:PEP06, a polypeptide modified from endostatin, was investigated for its antitumour effects on colorectal cancer (CRC) and the possible mechanisms of this antitumour activity were examined in in vitro and in vivo models. EXPERIMENTAL APPROACH:After PEP06 treatment, cell proliferation and migration assays were performed in CRC cells. Epithelial-mesenchymal transition (EMT) progression was determined by Western blotting, immunofluorescent staining and immunohistochemistry in vitro and in a residual xenograft model. MiRNAs regulated by PEP06 were identified by miRNA microarray and verified by in situ hybridization and quantitative real-time PCR. The interactions between PEP06 and integrin ?v?3 were determined with Biacore SA biochips. The cellular function of miR-146b-5p was validated by gain-of-function and loss-of-function approaches. A mouse model of lung metastasis was used to determine the effect of PEP06 on metastatic growth. KEY RESULTS:PEP06 did not affect cell viability but reduced migration and EMT in SW620 and HCT116 cells. PEP06 significantly repressed the expression of miR-146b-5p in these two cell lines through binding to integrin ?v?3. MiR-146b-5p was shown to increase EMT by targeting Smad4, and the miR-146b-5p-Smad4 cascade regulated EMT in CRC. PEP06 also suppressed CRC pulmonary metastasis, increased survival of mice and hampered residual tumour growth by inhibiting EMT through down-regulating miR-146b-5p. CONCLUSIONS AND IMPLICATIONS:PEP06 is a polypeptide that inhibits the growth and metastasis of colon cancer through its RGD motif binding to integrin ?v?3, thereby down-regulating miR-146b-5p to inhibit EMT in vitro and in vivo. It might have potential as a therapeutic for CRC.
Project description:Cancer cell-derived extracellular vesicles (EVs) have been reported to promote the progression of colorectal cancer (CRC), although the regulatory mechanism remains uncharacterized. In this study, we investigated the role of microRNA-25 (miR-25)/sirtuin 6 (SIRT6) in the contribution of EVs derived from CRC cells to progression of CRC. In a co-culture system with EVs from HCT116 and NCM460 cells, the viability, migratory, and invasive properties of SW480 and SW620 cells were evaluated by cell counting kit-8 (CCK-8) and Transwell assays. Luciferase, chromatin immunoprecipitation (ChIP), and RNA immunoprecipitation (RIP) assays were conducted to verify the interaction among miR-25, SIRT6, lin-28 homologB (Lin28b), and neuropilin-1 (NRP-1). It was established that HCT116 cell-derived EVs promoted the malignant properties of SW480 cells and SW620 cells by delivering miR-25. SIRT6 was targeted by miR-25, whereas SIRT6 inhibited NRP-1 through downregulation of Lin28b. The tumor-bearing nude mouse experiments substantiated that HCT116 cell-derived EVs transferred miR-25 to facilitate tumor formation and metastasis by inhibiting SIRT6. In summary, our study clarifies the involvement of miR-25-targeted SIRT6 inhibition and SIRT6-mediated inhibition of the Lin28b/NRP-1 axis in CRC cell-derived EVs to CRC progression and metastasis.
Project description:The human genome contains thousands of long intergenic noncoding RNAs (lincRNAs). However, the functional roles of these transcripts and the mechanisms responsible for their deregulation in colorectal cancer (CRC) remain elusive. A novel lincRNA termed upregulated in CRC (UCC) was found to be highly expressed in human CRC tissues and cell lines. UCC levels correlated with lymph node metastasis, Dukes' stage, and patient outcomes. In SW480 and SW620 cells, knockdown of UCC inhibited proliferation, invasion, and cell cycle progression and induced apoptosis in vitro. Xenograft tumors grown from UCC-silenced SW620 cells had smaller mean volumes and formed more slowly than xenograft tumors grown from control cells. Inversely, overexpression of UCC in HCT116 promoted cell growth and invasion in vitro. Bioinformatics analysis, dual-luciferase reporter assays, and RNA immunoprecipitation assays showed that miR-143 can interact with UCC, and we found that UCC expression inversely correlates with miR-143 expression in CRC specimens. Moreover, mechanistic investigations showed that UCC may act as an endogenous sponge by competing for miR-143, thereby regulating the targets of this miRNA. Our results suggest that UCC and miR-143 may be promising molecular targets for CRC therapy.