Long noncoding RNA AFAP1-AS1 acts as a competing endogenous RNA of miR-423-5p to facilitate nasopharyngeal carcinoma metastasis through regulating the Rho/Rac pathway.
ABSTRACT: BACKGROUND:Actin filament-associated protein 1 antisense RNA 1 (AFAP1-AS1), a long noncoding RNA, is significantly highly expressed and associated with metastasis and poor prognosis in many cancers, including nasopharyngeal carcinoma (NPC). In this study, we aim to identify the role of AFAP1-AS1 acting as an oncogenic lncRNA to promote NPC metastasis. METHODS:The role of AFAP1-AS1, miR-423-5p, and FOSL2 in NPC metastasis was investigated in vitro and in vivo. Bioinformatics analysis and luciferase activity assays were used to identify the interaction between AFAP1-AS1, miR-423-5p, and FOSL2. Additionally, real-time PCR and western blotting were used to assess the function of AFAP1-AS1 acting as an oncogenic lncRNA to promote NPC progression by regulating miR-423-5p and the downstream Rho/Rac pathway. RESULTS:In this study, we determined that AFAP1-AS1 functions as a competing endogenous RNA in NPC to regulate the Rho/Rac pathway through miR-423-5p. These interactions can mediate the expression of RAB11B, LASP1, and FOSL2 and accelerate cell migration and invasion via the Rho/Rac signaling pathway or FOSL2. AFAP1-AS1 and FOSL2 could competitively bind with miR-423-5p to regulate several molecules, including RAB11B and LASP1 of the Rho/Rac signaling pathway. AFAP1-AS1 can also regulate the expression of LASP1, which was transcriptionally regulated by FOSL2, resulting in increased migration and invasion of NPC cells via the Rho/Rac signaling pathway. CONCLUSIONS:The observations in this study identify an important role for AFAP1-AS1 as a competing endogenous RNA (ceRNA) in NPC pathogenesis and indicate that it may serve as a potential target for cancer diagnosis and treatment.
Project description:Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related death worldwide. This study aims to understand the underlying mechanism of lncRNA, actin filament-associated protein 1 antisense RNA 1(AFAP1-AS1) in mediating chemotherapeutic resistance in NSCLC. The levels of AFAP1-AS1 in NSCLC tissues and cells were determined using RT-PCR. The protein levels of RRM2, EGFR, and p-AKT were analyzed using Western blotting. Binding between AFAP1-AS1 and miR-139-5p was confirmed using dual luciferase reporter and RNA immunoprecipitation (RIP) assays, and binding between miR-139-5p and RRM2 was confirmed by a dual luciferase reporter assay. NSCLC cell proliferation, apoptosis, and colony formation were examined using MTT, flow cytometry, and colony formation assays, respectively. It was found that AFAP1-AS1 expression was upregulated in NSCLC tissues and cells. In addition, AFAP1-AS1 bound to and downregulated the expression of miR-139-5p, which was reduced in NSCLC tissues. Knockdown of AFAP1-AS1 and overexpression of miR-139-5p inhibited NSCLC cell proliferation, colony formation and chemotherapy resistance and increased cell apoptosis. Additionally, AFAP1-AS1 upregulates RRM2 expression via sponging miR-139-5p. Furthermore, AFAP1-AS1 enhanced NSCLC cell proliferation and chemotherapy resistance through upregulation of RRM2 by inhibiting miR-139-5p expression. Moreover, RRM2 promoted cellular chemotherapy resistance by activating EGFR/AKT. Finally, knockdown of AFAP1-AS1 significantly suppressed tumor growth and chemoresistance in nude mice. In conclusion, AFAP1-AS1 promoted chemotherapy resistance by supressing miR-139-5p expression and promoting RRM2/EGFR/AKT signaling pathway in NSCLC cells.
Project description:BACKGROUND:Melanoma is the most aggressive skin cancer that derived from pigment cells, accounting for the majority of the skin-cancer-related deaths. Despite great development and evolution have been made in surgery, radiotherapy and adjuvant chemotherapy, the prognosis of melanoma patients exhibited no significant improvement. Long noncoding RNAs (lncRNAs) are frequently dysregulated and involved in the development of cancers. LncRNA AFAP1-AS1 has been explored in various cancers, whereas its role and regulatory mechanism in melanoma are not well understood. METHODS:The expression of AFAP1-AS1 was detected by qRT-PCR. CCK-8, colony formation, transwell and western blot assays were performed to investigate the biological role of AFAP1-AS1 in melanoma. Male BALB/c nude mice were applied for in vivo experiments. The interaction among AFAP1-AS1, miR-653-5p and RAI14 was investigated by RNA pull down, RIP and luciferase reporter assays. RESULTS:AFAP1-AS1 was highly expressed in melanoma cell lines. Suppression of AFAP1-AS1 impaired cell proliferation, migration, invasion and EMT in melanoma. Moreover, AFAP1-AS1 was a ceRNA of RAI14 by competitively binding with miR-653-5p. Besides, miR-653-5p overexpression or RAI14 inhibition could repress tumor growth. Eventually, rescue assays indicated that the function of AFAP1-AS1 in the cellular process of melanoma was dependent on miR-653-5p and RAI14. CONCLUSIONS:AFAP1-AS1 exerts its oncogenic function in melanoma by targeting miR-653-5p/RAI14 axis.
Project description:Altered expression of long noncoding RNAs (lncRNAs) associated with human carcinogenesis. We performed a cDNA microarray analysis of lncRNA expression in 12 cases of nasopharyngeal carcinoma (NPC) and 4 non-tumor nasopharyngeal epitheliums. One lncRNA, actin filament associated protein 1 antisense RNA1 (AFAP1-AS1), was identified and selected for further study. AFAP1-AS1 expression was upregulated in NPC and associated with NPC metastasis and poor prognosis. In vitro experiments demonstrated that AFAP1-AS1 knockdown significantly inhibited the NPC cell migration and invasive capability. AFAP1-AS1 knockdown also increased AFAP1 protein expression. Proteomic and bioinformatics analyses suggested that AFAP1-AS1 affected the expression of several small GTPase family members and molecules in the actin cytokeratin signaling pathway. AFAP1-AS1 promoted cancer cell metastasis via regulation of actin filament integrity. AFAP1-AS1 might be a potential novel marker that can predict cancer patient prognosis and as a potential therapeutic target for NPC.
Project description:Nasopharyngeal carcinoma (NPC) carries a high potential for metastasis and immune escape, with a great risk of relapse after primary treatment. Through analysis of whole genome expression profiling data in NPC samples, we found that the expression of a long non-coding RNA (lncRNA), actin filament-associated protein 1 antisense RNA 1 (AFAP1-AS1), is significantly correlated with the immune escape marker programmed death 1 (PD-1). We therefore assessed the expression of AFAP1-AS1 and PD-1 in a cohort of 96 paraffin-embedded NPC samples and confirmed that AFAP1-AS1 and PD-1 are co-expressed in infiltrating lymphocytes in NPC tissue. Moreover, patients with high expression of AFAP1-AS1 or PD-1 in infiltrating lymphocytes were more prone to distant metastasis, and NPC patients with positive expression of both AFAP1-AS1 and PD-1 had the poorest prognosis. This study suggests that AFAP1-AS1 and PD-1 may be potential therapeutic targets in NPC and that patients with co-expression of AFAP1-AS1 and PD-1 may be ideal candidates for future clinical trials of anti-PD-1 immune therapy.
Project description:OBJECTIVE:To investigate the expression of long-chain noncoding growth stasis specific protein 6 antisense RNA1 (lncRNA DLX6-AS1) in nasopharyngeal carcinoma (NPC) tissues and cells, and its regulatory effect on malignant phenotypes of NPC cells. METHODS:The expressions of DLX6-AS1, miR-199a-5p, and HIF-1? mRNA in NPC issues and cells were detected by qRT-PCR. The proliferation, metastasis, and invasion of cells were monitored via MTT and transwell assay. The interactions between DLX6-AS1 and miR-199a-5p, miR-199a-5p and HIF-1? were verified by luciferase activity assay. Western blot was performed to determine the regulatory effect of DLX6-AS1 and miR-199a-5p on HIF-1? protein. RESULTS:The expression of lncRNA DLX6-AS1 was up-regulated in NPC tissues and cells. The proliferation, migration, and invasion of NPC were enhanced by overexpressed DLX6-AS1 but inhibited by DLX6-AS1 knockdown. In addition, DLX6-AS1 can be used as a kind of ceRNA to regulate miR-199a-5p and, thereby modulating the expression of HIF-1?. CONCLUSION:We found that DLX6-AS1 was a cancer-promoting lncRNA to facilitate the progression of NPC, and its underlying mechanism was suppressing miR-199a-5p expression. This study can provide novel clues for the treatment of NPC.
Project description:Background:Nasopharyngeal carcinoma (NPC) is a subtype of head and neck cancer with dismal prognosis and high relapse rate. The role of long non-coding RNAs (lncRNAs) in NPC has become a research hotspot in recent years. This study aimed to interrogate the function and mechanism of lncRNA MSC antisense RNA 1 (MSC-AS1) in NPC. Methods:MSC-AS1 level in NPC tissues and cells were detected by RT-qPCR. Function of MSC-AS1 in NPC cells was assessed by CCK-8, EdU, TUNEL, caspase-3 activity, and transwell invasion assay. Interaction of microRNA-524-5p (miR-524-5p) with MSC-AS1 and nuclear receptor subfamily 4 group A member 2 (NR4A2) was determined by RIP and luciferase reporter assays. Results:MSC-AS1 was upregulated in NPC tissues and cells. Functional assays indicated that MSC-AS1 exacerbated cell proliferation, hindered apoptosis, and facilitated invasion and epithelial-to-mesenchymal transition (EMT) in NPC. Mechanistically, MSC-AS1 sequestered miR-524-5p to upregulate NR4A2 expression in NPC cells. Finally, NR4A2 was conformed as an oncogene in NPC, and overexpressed NR4A2 could restore MSC-AS1 knockdown-mediated inhibition on NPC progression. Conclusions:Our study firstly showed that lncRNA MSC-AS1 aggravated NPC progression by sponging miR-524-5p to increase NR4A2 expression, indicating MSC-AS1 as a novel target for the lncRNA-targeted therapy in NPC.
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.
Project description:The actin fiber-associated protein 1-antisense RNA1 (AFAP1-AS1) is upregulated in various cancers and associated with cancer proliferation and metastasis. Several cancer-related pathways have been linked to up-expression of this long non-coding (lnc)RNA, but the underlying mechanisms are yet unknown. In triple negative breast cancer (TNBC), AFAP1-AS1 expression is also significantly overexpressed compared to that in other subtypes of breast cancer from the TCGA dataset. In this study, we performed bioinformatic RNAhybrid analyses and identified that miR-145 is a potential target of AFAP1-AS1 and able to reduce MutT homolog-1 (MTH1) expression. Thus, this study investigated the oncogenic activity of AFAP1-AS1 in TNBC cells and the underlying mechanisms that are yet poorly understood. The results showed that miR-145 expression was low, whereas AFAP1-AS1 and MTH1 expression was high in TNBC cells and that miR-145 mimics reduced TNBC cell proliferation and invasion, whereas miR-145 knockdown exerted the opposite activity in TNBC cells. Moreover, knockdown of AFAP1-AS1 reduced tumor cell proliferation and invasion, but miR-145 co-transfection rescued tumor cell viability and colony formation ability. The dual luciferase reporter assay showed that AFAP1-AS1 could directly target miR-145, while miR-145 could directly target MTH1. After knockdown of ATF6, AFAP1-AS1 was reduced along with AFAP1-AS1 promoter activity. This study revealed that AFAP1-AS1 could promote TNBC cell proliferation and invasion via regulation of MTH1 expression through targeting of miR-145.
Project description:Purpose:In view of the continuous increase of the mortality rate, esophageal squamous cell carcinoma (ESCC) develops into a major health concern. In this study, we aimed to investigate the underlying mechanism of long noncoding RNA (lncRNA) actin filament-associated protein 1 antisense RNA (AFAP1-AS1)/microRNA-498 (miR-498)/vascular endothelial growth factor A (VEGFA) in ESCC cells. Methods:The expression levels of AFAP1-AS1, miR-498 and VEGFA in ESCC tissues and cells were detected using quantitative real-time polymerase chain reaction (qRT-PCR). The effects of AFAP1-AS1 on ESCC cells proliferation and apoptosis were measured by methyl thiazolyl tetrazolium (MTT) and flow cytometry, respectively. Transwell assay was carried out to determine cell migration. In addition, VEGFA and cell behaviors-related proteins were determined by Western blot analysis. The targeted relationships of AFAP1-AS1 were verified by dual-luciferase reporter and RNA pull-down assays. Results:The expression levels of lncRNA AFAP1-AS1 and VEGFA mRNA were upregulated, but miR-498 was downregulated in ESCC tissues and cells. Moreover, miR-498 was directly targeted by AFAP1-AS1 and there was a negative correlation between miR-498 and AFAP1-AS1. Functionally, AFAP1-AS1 silencing inhibited the proliferation and migration and induced apoptosis of ESCC cells. Interestingly, miR-498 inhibition rescued the effects of AFAP1-AS1 knockdown on cell proliferation, apoptosis and migration and restored the expression levels of tumor-developing marker proteins of AFAP1-AS1 silencing in Eca109 and KYSE-30 cells. Furthermore, VEGFA was verified as a direct target of miR-498 and reversed the effects of miR-498 overexpression on cell behaviors of ESCC in vitro. Conclusion:Downregulation of AFAP1-AS1 impeded the proliferation and migration and induced apoptosis of ESCC cells by regulating miR-498/VEGFA axis, which might serve as a novel biomarker for the diagnosis and treatment of ESCC.
Project description:<h4>Background</h4>Pancreatic cancer (PC) represents one of the most aggressive forms of cancer. The role of long non-coding RNAs (lncRNAs) has been highlighted in various malignancies including PC. The aim of the present study was to investigate the effects associated with actin filament-associated protein 1 antisense RNA 1 (AFAP1-AS1) on the progression of PC and the underlying mechanism.<h4>Methods</h4>Microarray-based gene expression profiling of PC was performed to identify PC-related lncRNAs, after which the expression of AFAP1-AS1 and cancer stem cell (CSC) markers in PC tissues and cells were determined accordingly. The potential microRNA-384 (miR-384) capable of binding to AFAP1-AS1, in addition to its ability to regulate activin receptor A type I (ACVR1) were analyzed. In order to investigate the effect of the AFAP1-AS1/miR-384/ACVR1 axis on self-renewal ability, tumorigenicity, invasion, migration and stemness of PC cells, shRNA-AFAP1-AS1, miR-384 mimic and inhibitor were cloned into cells.<h4>Results</h4>High expression of AFAP1-AS1 and ACVR1 with low expression of miR-384 were detected in PC tissues. ACVR1 was determined to be down-regulated when miR-384 was overexpressed, while the inhibition of AFAP1-AS1 decreased its ability to binding competitively to miR-384, resulting in the down-regulation of ACVR1 and enhancing miR-384 expression, ultimately inhibiting the progression of PC. The knockdown of AFAP1-AS1 or overexpression of miR-384 was confirmed to impair PC cell self-renewal ability, tumorigenicity, invasion, migration and stemness.<h4>Conclusions</h4>Taken together, AFAP1-AS1 functions as an endogenous RNA by competitively binding to miR-384 to regulate ACVR1, thus conferring inhibitory effects on PC cell stemness and tumorigenicity.