Long Non-Coding RNA LINC00525 Promotes the Stemness and Chemoresistance of Colorectal Cancer by Targeting miR-507/ELK3 Axis.
Ontology highlight
ABSTRACT: Background and objectives
This study aims to explore the effects of a long non-coding RNA, LINC00525, on colorectal cancer (CRC) and its underlying molecular mechanisms.Methods
The qPCR, MTT, colony formation, Western blotting, Luciferase reporter and biotin pull-down, shRNA knockdown and DNA fragmentation assays were performed in this study.Results
High expressions of LINC00525 were associated with poor prognosis of CRC patients. LINC00525 knockdown decreased stemness properties and increased sensitivities to oxaliplatin. MiR-507 was a direct target of LINC00525 and overexpression of miR-507 significantly decreased abilities of tumorsphere formation and cell growth. Overexpression of miR-507 resulted in a decrease of expression of cancer stem cell markers and the increase of apoptosis rates. MiR-507 regulated the expression of ELK3. In addition, LINC00525 knockdown decreased the expression of ELK3. Restoration of ELK3 expression abrogated the effects of LINC00525 knockdown. LINC00525 could be served as prognostic marker of CRC.Conclusions
LINC00525 enhanced stemness properties and increased sensitivities of CRC cells to oxaliplatin by targeting miR-507/ELK3 axis.
SUBMITTER: Wang S
PROVIDER: S-EPMC6657946 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:AFAP1-AS1 is a long non-coding RNA that is associated with tumorigenesis and poor prognosis in a variety of cancers. We have been suggested that AFAP1-AS1 increases tumorigenesis in laryngeal carcinoma specifically by enhancing stemness and chemoresistance. We assessed AFAP1-AS1 expression in human laryngeal specimens, paired adjacent normal tissues and human HEp-2 cells. Indeed, we found not only that AFAP1-AS1 was up-regulated in laryngeal carcinoma specimens and cells, but also that stemness-associated genes were overexpressed. Silencing of AFAP1-AS1 promoted HEp-2 cell chemoresistance under cisplatin treatment. Expression of AFAP1-AS1 was increased in drug-resistant Hep-2 cells. We then probed the mechanism of AFAP1-AS1 activity and determined that miR-320a was a potential molecular target of AFAP1-AS1. Luciferase reporter and qRT-PCR assays of AFAP1-AS1 and miR-320a levels in human specimens and cell cultures indicated that AFAP1-AS1 negatively regulates miR-320a. To discover the molecular mechanism of miR-320a, we again used the DIANA Tools algorithm to predict its genetic target, RBPJ. After cloning the 3'-untranslated regions (3'-UTR) of RBPJ into a luciferase reporter, we determined that miR-320a did in fact reduce RBPJ mRNA and protein levels. Ultimately, we determined that AFAP1-AS1 increases RBPJ expression by negatively regulating miR-320a and RBPJ overexpression rescues stemness and chemoresistance inhibited by AFAP1-AS1 silencing. Taken together, these results suggest that AFAP1-AS1 can serve as a prognostic biomarker in laryngeal carcinoma and that miR-320a has the potential to improve standard therapeutic approaches to the disease, especially for cases in which cancer cell stemness and drug resistance present significant barriers to effective treatment.
| S-EPMC6111816 | biostudies-other
Project description:Colorectal cancer (CRC) remains both common and fatal, and its successful treatment is greatly limited by the development of stem cell-like characteristics (stemness) and chemoresistance. MiR-30-5p has been shown to function as a tumor suppressor by targeting the Wnt/?-catenin signaling pathway, but its activity in CRC has never been assessed. We hypothesized that miR-30-5p exerts anti-oncogenic effects in CRC by regulating the USP22/Wnt/?-catenin signaling axis. In the present study, we demonstrate that tissues from CRC patients and human CRC cell lines show significantly decreased miR-30-5p family expression. After identifying the 3'UTR of USP22 as a potential binding site of miR-30-5p, we constructed a luciferase reporter containing the potential miR-30-5p binding site and measured the effects on USP22 expression. Western blot assays showed that miR-30-5p decreased USP22 protein expression in HEK293 and Caco2 CRC cells. To evaluate the effects of miR-30-5p on CRC cell stemness, we isolated CD133 + CRC cells (Caco2 and HCT15). We then determined that, while miR-30-5p is normally decreased in CD133 + CRC cells, miR-30-5p overexpression significantly reduces expression of stem cell markers CD133 and Sox2, sphere formation, and cell proliferation. Similarly, we found that miR-30-5p expression is normally reduced in 5-fluorouracil (5-FU) resistant CRC cells, whereas miR-30-5p overexpression in 5-FU resistant cells reduces sphere formation and cell viability. Inhibition of miR-30-5p reversed the process. Finally, we determined that miR-30-5p attenuates the expression of Wnt/?-catenin signaling target genes (Axin2 and MYC), Wnt luciferase activity, and ?-catenin protein levels in CRC stem cells.
| S-EPMC6307779 | biostudies-literature
Project description:BackgroundLong noncoding RNAs (lncRNAs) are related to colorectal cancer (CRC) development. However, the role and mechanism of lncRNA LINC01224 in CRC development are largely unknown.MethodsLINC01224, Yin Yang 1 (YY1), microRNA (miR)-485-5p, and myosins of class VI (MYO6) levels were examined using quantitative reverse transcription polymerase chain reaction and western blotting. Functional analyses were processed through CCK-8, colony formation, flow cytometry, transwell, and xenograft analyses. Dual-luciferase reporter, chromatin immunoprecipitation (ChIP), RNA immunoprecipitation, and pull-down assays were conducted to analyze the binding interaction.ResultsLINC01224 abundance was elevated in CRC tissue samples and cell lines. Elevated LINC01224 might indicate the lower 5-year overall survival in 52 CRC patients. LINC01224 was upregulated via the transcription factor YY1. LINC01224 knockdown restrained CRC cell proliferation, migration, and invasion and increased apoptosis. MiR-485-5p was sponged by LINC01224, and miR-485-5p downregulation relieved the influence of LINC01224 interference on CRC progression. MYO6 was targeted via miR-485-5p and regulated via LINC01224/miR-485-5p axis. MiR-485-5p overexpression suppressed CRC cell proliferation, migration, and invasion and facilitated apoptosis. MYO6 upregulation mitigated the role of miR-485-5p. LINC01224 knockdown decreased xenograft tumor growth.ConclusionYY1-induced LINC01224 regulates CRC development via modulating miR-485-5p/MYO6 axis.
| S-EPMC8449439 | biostudies-literature
Project description:Metastasis and chemoresistance indicate treatment fail and progresses in gastric cancer (GC) patients. However, the molecular mechanisms of chemoresistance and metastasis remain unclear in GC. Thus, identifying the biological indicators of chemoresistance and metastasis is particularly important. We establish a role for miR-492 in GC metastasis and chemoresistance through experiments in vitro and in vivo. We identified miR-492 overexpression in GC specimens and cell lines, the miR-492 expression level was inversely correlated with the prognosis of GC patients. The inhibition of miR-492 suppressed GC cell invasion and enhanced the sensitivity of gastric cancer cells to CDDP treatment. In contrast, miR-492 overexpression significantly stimulated GC cell invasion and contributed to chemoresistance development. In addition, our research results indicated that the inhibition of miR-492 stimulates GC stemness, and the overexpression of miR-492 induces GC stemness. Importantly, our experiments demonstrated that miR-492 inhibitor suppressed tumor formation, and the combination treatment of miR-492 inhibitor and CDDP significantly inhibited tumor growth in vivo. Furthermore, we demonstrated that miR-492 exerts its anticancer role by targeting DNMT3B in GC. Our results suggested that inhibiting miR-492 is a novel strategy to control tumor metastasis and chemoresistance in GC.
| S-EPMC7064790 | biostudies-literature
Project description:Long non-coding RNAs(lncRNAs) play an important role in cancer initiation and progression. However, hub lncRNAs involved in breast cancer still remain underexplored. In this study, integrated bioinformatics analysis was used to define LINC01977 as a key oncogenic driver in breast cancer. Subsequently, in vitro assays showed that LINC01977 could significantly promote breast cancer progression and chemoresistance to doxorubicin. To further investigate its biological mechanism, we performed dual-luciferase reporter assay, real-time PCR, RNA immunoprecipitation (RIP), and rescue assay. Our results indicated that LINC01977 may function as ceRNA to prevent GOLM1 gene from miRNA-mediated repression by sponging miR-212-3p. Overall, LINC01977 can serve as a novel prognostic indicator, and help develop more effective therapeutic approaches for breast cancer patients.
| S-EPMC8046671 | biostudies-literature
Project description:Malignant tumors, including colorectal cancer (CRC), usually rely on ATP generation through aerobic glycolysis for both rapid growth and chemotherapy resistance. The M2 isoform of pyruvate kinase (PKM2) has a key role in catalyzing glycolysis, and PKM2 expression varies even within a single tumor. In this study, we confirmed that expression of PKM2 is heterogeneous in CRC cells, namely high in oxaliplatin-resistant cells but relatively low in sensitive cells, and found that chemoresistant cells had enhanced glycolysis and ATP production. In addition, we report a PKM2-dependent mechanism through which chemosensitive cells may gradually transform into chemoresistant cells. The circular RNA hsa_circ_0005963 (termed ciRS-122 in this study), which was determined to be a sponge for the PKM2-targeting miR-122, was positively correlated with chemoresistance. In vitro and in vivo studies showed that exosomes from oxaliplatin-resistant cells delivered ciRS-122 to sensitive cells, thereby promoting glycolysis and drug resistance through miR-122 sponging and PKM2 upregulation. Moreover, si-ciRS-122 transported by exosomes could suppress glycolysis and reverse resistance to oxaliplatin by regulating the ciRS-122-miR-122-PKM2 pathway in vivo. Exosomes derived from chemoresistant CRC cells could transfer ciRS-122 across cells and promote glycolysis to reduce drug susceptibility in chemosensitive cells. This intercellular signal delivery suggests a potential novel therapeutic target and establishes a foundation for future clinical applications in drug-resistant CRC.
| S-EPMC7053238 | biostudies-literature
Project description:Objective: Long non-coding RNAs (lncRNAs) are critical to colorectal cancer (CRC) progression. In the current study, the objective was the exploration of the role played by lncRNA MIR4435-2HG in CRC proliferation and metastasis. Methods: lncRNA MIR4435-2HG expression and its association with CRC were analyzed using database and clinical specimens. The influences exerted by MIR4435-2HG on cell proliferating process, invading process, and migrating process of CRC were identified after MIR4435-2HG knockdown. The influences exerted by MIR4435-2HG on tumor growth and metastasis were assessed in vivo. The underlying mechanistic associations between MIR4435-2HG, microRNA miR-206, and the transcription factor Yes-associated protein 1 (YAP1) were assessed using bioinformatics and a luciferase reporter gene assay. Results: MIR4435-2HG was highly expressed in CRC tissue in contrast with that in regular tissues and displayed relations to poor prognosis. MIR4435-2HG knockdown could suppress CRC cell proliferation, invasion, and migration. Moreover, MIR4435-2HG knockdown inhibited CRC growth and liver metastasis in vitro. We found MIR4435-2HG knockdown reduced YAP1, CTGF, AREG, vimentin, Snail, Slug, and Twist expression but enhanced E-cadherin expression. Functionally, MIR4435-2HG acted as a competing endogenous RNA (ceRNA) to upregulate YAP1 by sponging miR-206. Conclusions: MIR4435-2HG promoted CRC growth and metastasis through miR-206/YAP1 axis and is likely to play prognostic marker roles and be therapeutically targeted in CRC.
| S-EPMC7044350 | biostudies-literature
Project description:BackgroundChemoresistance is the major cause of chemotherapy failure in patients with colorectal cancer (CRC). Protein tyrosine kinase 6 (PTK6) is aberrantly overexpressed in clinical CRC tissues undergoing chemotherapy. We studied if PTK6 contributed to the chemoresistance of CRC in human and mice.MethodsWe obtained tissue samples from patients with CRC and measured the expression of PTK6 by immunohistochemistry. Gain- and loss-of-function assays were performed to study the biological functions of PTK6. We constructed the FLAG-tagged wild type (WT), kinase-dead, and inhibition-defective recombinant mutants of PTK6 to study the effect phosphorylated activation of PTK6 played on CRC cell stemness and chemoresistance. We used small molecule inhibitor XMU-MP-2 to test the influence of PTK6 on sensitivity of CRC cells to 5-FU/L-OHP in both nude mouse and patient-derived xenograft (PDX) animal models.ResultsPTK6 is overexpressed in CRC tissues and plays a stimulatory role in the proliferation and chemoresistance of CRC cells both in vitro and in vivo. PTK6, especially the phosphorylated PTK6, can promote the stemness of CRC cells through interacting with JAK2 and phosphorylating it to activate the JAK2/STAT3 signaling. Pharmacological inhibition of PTK6 using XMU-MP-2 effectively reduces the stemness property of CRC cells and improves its chemosensitivity to 5-FU/L-OHP in both nude mice subcutaneously implanted tumor model and PDX model constructed with NOD-SCID mice.ConclusionsPTK6 interacts with JAK2 and phosphorylates it to activate JAK2/STAT3 signaling to promote the stemness and chemoresistance of CRC cells. Pharmacological inhibition of PTK6 by small molecule inhibitor dramatically enhances the sensitivity to chemotherapy in nude mice and PDX models.
| S-EPMC8456648 | biostudies-literature
Project description:BackgroundCancer stem cell (CSC)-related chemoresistance leads to poor outcome of the patients with colorectal cancer (CRC). In this study, we identified the chemoresistance-relevant molecules and decipher the involved mechanisms to provide potential therapeutic target for CRC. We focused on Sec62, a novel target with significantly increased expression in chemoresistant CRC tissues, and further investigated its role in the progression of CRC.MethodsThrough analyzing the differentially-expressed genes between chemoresistant and chemosensitive CRCs, we selected Sec62 as a novel chemoresistance-related target in CRC. The expression and clinical significance of Sec62 were determined by immunoblotting and immunohistochemistry in tissues and cell lines of CRC. The roles of Sec62 in drug resistance, stemness and tumorigenesis were evaluated in vitro and in vivo using functional experiments. GST pull-down, western blot, coimmunoprecipitation and Me-RIP assays were performed to further explore the downstream molecular mechanisms.ResultsSec62 upregulation was associated with the chemoresistance of CRC and poor outcome of CRC patients. Depletion of Sec62 sensitized CRC cells to chemotherapeutic drugs. Sec62 promoted the stemness of CRC cells through activating Wnt/β-catenin signaling. Mechanistically, Sec62 bound to β-catenin and inhibited the degradation of β-catenin. Sec62 competitively disrupted the interaction between β-catenin and APC to inhibit the β-catenin destruction complex assembly. Moreover, Sec62 expression was upregulated by the m6A-mediated stabilization of Sec62 mRNA.ConclusionsSec62 upregulated by the METTL3-mediated m6A modification promotes the stemness and chemoresistance of CRC by binding to β-catenin and enhancing Wnt signalling. Thus, m6A modification-Sec62-β-catenin molecular axis might act as therapeutic targets in improving treatment of CRC.
| S-EPMC8051072 | biostudies-literature
Project description:Background:Rhophilin Rho GTPase binding protein 1 antisense RNA 1 (RHPN1-AS1) is a newly discovered oncogene in several diseases, such as breast cancer, non-small cell lung cancer and uveal melanoma. Nevertheless, its molecular role in colorectal cancer (CRC) remains unknown. This paper explored the role of RHPN1-AS1 in CRC progression. Methods:qRT-PCR was used to detect relevant RNAs expression. CCK-8, EdU, flow cytometry, Transwell and western blot assays were performed to investigate the function of RHPN1-AS1 in CRC cells. Xenograft model was constructed to evaluate the effects of RHPN1-AS1 on tumor growth in vivo. Mechanical experiments were performed to investigate the relationship between relative genes. Results:RHPN1-AS1 was significantly overexpressed in CRC cell lines. Knockdown of RHPN1-AS1 could inhibit cell proliferation, while stimulating cell apoptosis in vitro. Cell migration and invasion abilities were greatly suppressed after silencing RHPN1-AS1. Besides, signal transducer and activator of transcription 3 (STAT3) served as transcription factor of RHPN1-AS1. Moreover, miR-7-5p was identified as a target of RHPN1-AS1 and was negatively regulated by RHPN1-AS1 in CRC. MiR-7-5p inhibition rescued the oncogenic function of RHPN1-AS1. Additionally, O-GlcNAcylation transferase (OGT) was the downstream target of miR-7-5p. OGT overexpression could abrogate the anti-tumor effects of RHPN1-AS1 knockdown on CRC. Conclusion:RHPN1-AS1 regulates CRC by mediating OGT through sponging miR-7-5p, suggesting that RHPN1-AS1 might be a potential therapeutic target for CRC.
| S-EPMC7029493 | biostudies-literature