Long non-coding RNA ZFAS1 promotes nasopharyngeal carcinoma through activation of Wnt/β-catenin pathway

Research Progress of Long Non-coding RNA-ZFAS1 in Malignant Tumors

Long non-coding RNAs (lncRNAs), although incapable of encoding proteins, play crucial roles in multiple layers of gene expression regulation, epigenetic modifications, and post-transcriptional regulation. Zinc finger antisense 1 (ZFAS1), a lncRNA located in the 20q13 region of the human genome, exhibits dual functions as an oncogene or tumor suppressor in various human malignancies. ZFAS1 plays a crucial role in cancer progression, metastasis, invasion, apoptosis, cell cycle regulation, and drug resistance through complex molecular mechanisms. Additionally, ZFAS1 has a long half-life of over 16 h, demonstrating exceptional stability, and making it a potential biomarker. This review integrates recent studies on the role and molecular mechanisms of ZFAS1 in malignancies and summarizes its clinical significance. By summarizing the role of ZFAS1 in cancer, we aim to highlight its potential as an anti-cancer biomarker and therapeutic target.

[Interference of long noncoding RNA FOXCUT inhibits epithelial-mesenchymal transformation and induces mitochondrial injury in nasopharyngeal carcinoma cells]

OBJECTIVE

To investigate the effects of RNA interference of long noncoding RNA FOXCUT on epithelial mesenchymal transformation and mitochondrial function in nasopharyngeal carcinoma (NPC) cells.

METHODS

FOXCUT expression levels were detected by RT-PCR in tumor tissues and adjacent tissues from 50 patients with NPC and in NP69, CNE1, CNE2, SUNE2, HER2 and 5-8F cell lines. CNE1 cells were transfected with a short hairpin RNA (shRNA) targeting FOXCUT or a negative control RNA construct (shRNA-NC), and the changes in cell proliferation and morphology were assessed with CCK8 assay, clone formation assay and microscopic observation. An immunofluorescence assay was used to examine the vimentin-positive cells, and the levels of SOD, MDA and LDH in the cells were detected. The changes of mitochondrial membrane potential were detected with flow cytometry, and the expression levels of E-cad, N-cad, vimentin, Bax, Bcl-2, caspase-3 and c-Myc in the cells were detected with Western blotting.

RESULTS

The expression level of FOXCUT was significantly increased in NPC tissues as compared with the adjacent tissues (P < 0.001). Compared with NP69 cells, CNE1, CNE2, SUNE2, HER2 and 5-8F cells all exhibited significantly increased expressions of FOXCUT (P < 0.001). In CNE1 cells, transfection with FOXCUT shRNA significantly inhibited cell proliferation and clone formation (P < 0.001), and caused obvious changes in cell morphology. FOXCUT knockdown significantly decreased the expressions of N-cad and vimentin, increased E- cad expression and the contents of MDA and LDH (P < 0.05), reduced vimentin- positive cells and the activity of SOD, and caused a shift of red fluorescent cells to green fluorescent cells and an increased percentage of green fluorescent cells. FOXCUT knockdown also resulted in significantly increased expressions of Bax/Bcl2 and cleaved Cas3/Cas3 and a lowered expression of c-Myc.

CONCLUSIONS

Interference of FOXCUT can inhibit the proliferation and epithelial-mesenchymal transformation, enhance oxidative stress, induce mitochondrial function injury, and promote apoptosis in NPC cells, suggesting the potential of FOXCUT interference for targeted treatment of NPC.

Long non-coding RNAs in nasopharyngeal carcinoma: biological functions and clinical applications

Nasopharyngeal carcinoma (NPC) is one of the most common head and neck malignancies. It has obvious ethnic and regional specificity. Long non-coding RNAs (LncRNAs) are a class of non-protein coding RNA molecules. Emerging research shows that lncRNAs play a key role in tumor development, prognosis, and treatment. With the deepening of sequence analysis, a large number of functional LncRNAs have been found in NPC, which interact with coding genes, miRNAs, and proteins to form a complex regulatory network. However, the specific role and mechanism of abnormally expressed lncRNAs in the pathogenesis of NPC is not fully understood. This article briefly introduced the concept, classification, and functional mechanism of lncRNAs and reviewed their biological functions and their clinical applications in NPC. Specifically, we described lncRNAs related to the occurrence, growth, invasion, metastasis, angiogenesis, and cancer stem cells of NPC; discussed lncRNAs related to Epstein-Barr virus infection; and summarized the role of lncRNAs in NPC treatment resistance. We have also sorted out lncRNAs related to Chinese medicine treatment. We believe that with the deepening of lncRNAs research, tumor-specific lncRNAs may become a new target for the treatment and a biomarker for predicting prognosis.

IncRNA ZFAS1 contributes to the radioresistance of nasopharyngeal carcinoma cells by sponging hsa-miR-7-5p to upregulate ENO2

Previous research revealed that lncRNA ZFAS1 could promote nasopharyngeal carcinoma (NPC) by inhibiting its downstream target axis. However, the association between ZFAS1 and radioresistant NPC cells is unclear. This study aimed to explore the roles of ZFAS1 in the radioresistance of NPC. Bioinformatics analysis was conducted to identify the significant factors (ENO2 and miR-7-5p) that contributed to the radioresistance of NPC cells. After performing qRT-PCR analysis, we found that the expression of ZFAS1 and ENO2 was upregulated in NPC cells but that the miR-7-5p expression was downregulated in the same samples. Apart from that, we noticed that ZFAS1 inhibition enhanced the sensitivity of NPC cells to radiation therapy by repressing cell proliferation and promoting cell apoptosis. Subsequently, we found that ZFAS1 could sponge miR-7-5p to upregulate ENO2, which was the target of miR-7-5p. Experimental results also indicated that the suppression of miR-7-5p inhibited the sensitivity of NPC cells to radiation therapy, thereby suppressing ENO2 expression. Overall, our findings suggested that ZFAS1 contributed to the radioresistance of NPC cells by regulating the miR-7-5p/ENO2 axis and that ZFAS1 might be a potential therapeutic target for addressing the radioresistance of NPC cells.

Knockdown of LncRNAZFAS1 suppresses cell proliferation and metastasis in non-small cell lung cancer

To evaluate the effects of LncRNAZFAS1 on cell proliferation and tumor metastasis in non-small cell lung cancer (NSCLC), we detected the expression level of LncRNAZFAS1 in NSCLC-related tissues and cells. qRT-PCR results revealed that LncRNAZFAS1 in tumor tissues was significantly higher than that in normal lung tissue, especially significantly up-regulated in stage III / IV and in metastatic NSCLC tissues. LncRNAZFAS1 expression was dramatically up-regulated in 4 NSCLC-related cells (A549, SPC-A1, SK-MES-1, and NCI-H1299), with having the highest expression level in A549 cells. Furthermore, we implemented a knockdown of LncRNAZFAS1 in A549 cells, and the results of CCK8 and Transwell assays suggested that knockdown of LncRNAZFAS1 significantly inhibited NSCLC cell proliferation and metastasis. Next, we constructed a tumor xenograft model to evaluate the effect of LncRNAZFAS1 on the NSCLC cell proliferation in vivo. The results indicated that knockdown of LncRNAZFAS1 dramatically inhibited A549 cells proliferation and repressed tumor growth. Additionally, knockdown of LncRNAZFAS1 drastically weakened the expressions of MMP2, MMP9 and Bcl-2 proteins, whereas noticeably strengthened the expression of BAX protein. Our results altogether suggest that knockdown of LncRNAZFAS1 has a negative effect on the proliferation and metastasis of NSCLC cell, which implying LncRNAZFAS1 is a potential unfavorable biomarker in patients with NSCLC.

Long noncoding RNA ZFAS1 promotes tumorigenesis and metastasis in nasopharyngeal carcinoma by sponging miR-892b to up-regulate LPAR1 expression

OBJECTIVE

In this study, we explored the NPC-specific expression of ZFAS1 and the mechanism of ZFAS1-mediated growth, aggressiveness and tumorigenesis in NPC.

METHODS

The expression profile of lncRNAs was detected in NPC tissues and matching para-carcinoma tissues using microarray analysis. LncRNA-miRNA and miRNA-mRNA interaction networks were constructed using the miRcode v11 and TargetScanHuman v7.2 web server and then validated using dual-luciferase assay. Western blot and RT-qPCR were performed to detect protein and RNA expression. The effects of ZFAS1, miR-892b and LPAR1 dysregulation on the proliferative, migratory and invasive abilities of NPC cells were observed using colony formation, cell counting kit-8 (CCK-8) and transwell assays in vitro. In vivo, a xenograft nude mouse model was established to detect the impact of ZFAS1 dysregulation on the tumorigenicity of NPC cells.

RESULTS

The expression of multiple lncRNAs, of which ZFAS1 was up-regulated, was dysregulated in NPC tissues. ZFAS1 directly targeted miR-892b, and miR-892b negatively regulated the expression of downstream LPAR1. The proliferation, migration and invasion of NPC cells could be largely enhanced by the downregulation of miR-892b as well as the up-regulation of ZFAS1 and LPAR1, while the overexpression of miR-892b and the downregulation of ZFAS1 and LPAR1 decreased these abilities. In nude mice, the growth of tumour xenografts formed by HONE1 cells was significantly suppressed when ZFAS1 was silenced.

CONCLUSION

The study demonstrated that lncRNA ZFAS1 may act as a promoter of tumorigenesis and metastasis in nasopharyngeal carcinoma, by up-regulating the expression of LPAR1 in a miR-892b-dependent manner.

LncRNA ZFAS1 serves as a prognostic biomarker to predict the survival of patients with ovarian cancer

Ovarian cancer (OC) is one of the most fatal types of gynecological malignancy. Certain long non-coding RNAs (lncRNA) have been reported to have crucial roles in cancer progression. Zinc finger nuclear transcription factor, X-box binding 1-type containing 1 antisense RNA 1 (ZFAS1) is a novel regulator lncRNA in various cancer types. The expression pattern of most lncRNAs, including ZFAS1, in OC remains to be determined. In the present study, it was demonstrated that ZFAS1 was overexpressed in OC vs. normal cell lines. However, ZFAS1 was downregulated in OC compared with normal samples in the GEPIA dataset. Furthermore, OC samples of higher stages (stage III/IV) had higher levels of ZFAS1 compared with those in early-stage OC (stage I/II) samples. Of note, higher ZFAS1 expression was associated with shorter overall survival time and disease-free survival time of OC patients. Protein-protein interaction networks of proteins co-expressed with ZFAS1 in OC were constructed. Furthermore, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis of genes co-expressed with ZFAS1 indicated that ZFAS1 is associated with translation, mRNA splicing, cell-cell adhesion, DNA repair, protein sumoylation, positive regulation of GTPase activity and DNA replication. The present study may provide novel clues to validate ZFAS1 as a biomarker in OC.

Long noncoding RNA PXN-AS1-L promotes the malignancy of nasopharyngeal carcinoma cells via upregulation of SAPCD2

Accumulating evidences highlight the critical roles of long noncoding RNAs (lncRNAs) in a variety of cancers. LncRNA PXN‐AS1‐L was previously shown to exert oncogenic roles in hepatocellular carcinoma. However, the expression, role, and molecular mechanism of PXN‐AS1‐L in nasopharyngeal carcinoma (NPC) malignancy remain unknown. Here, we determined that PXN‐AS1‐L is upregulated in NPC tissues and cell lines. Increased expression of PXN‐AS1‐L predicts worse prognosis of NPC patients. PXN‐AS1‐L overexpression promotes NPC cell proliferation, migration, and invasion in vitro, and NPC tumor growth in vivo. PXN‐AS1‐L silencing suppresses NPC cell proliferation, migration, and invasion in vitro. Mechanistically, PXN‐AS1‐L directly interacts with SAPCD2 mRNA 3′‐untranslated region, prevents the binding of microRNAs‐AGO silencing complex to SAPCD2 mRNA, and upregulates the mRNA and protein level of SAPCD2. SAPCD2 is also increased in NPC tissues. The expression of SAPCD2 is significantly positively associated with that of PXN‐AS1‐L in NPC tissues. Gain‐of‐function and loss‐of‐function experiments demonstrated that SAPCD2 also promotes NPC cell proliferation, migration, and invasion. Furthermore, depletion of SAPCD2 significantly reverses the roles of PXN‐AS1‐L in promoting NPC cell proliferation, migration, and invasion in vitro, and NPC tumor growth in vivo. In conclusion, lncRNA PXN‐AS1‐L is upregulated in NPC and promoted NPC malignancy by upregulating SAPCD2 via direct RNA‐RNA interaction.

Identification of a putative competitive endogenous RNA network for lung adenocarcinoma using TCGA datasets

The mechanisms underlying the oncogenesis and progression of lung adenocarcinoma (LUAD) are currently unclear. The discovery of competitive endogenous RNA (ceRNA) regulatory networks has provided a new direction for the treatment and prognosis of patients with LUAD. However, the mechanism of action of ceRNA in LUAD remains elusive. In the present study, differentially expressed mRNAs, microRNAs (miRs) and long non-coding RNAs from the cancer genome atlas database were screened. CeRNAs for LUAD were then identified using online prediction software. Among the ceRNAs identified, family with sequence similarity 83 member A (FAM83A), miR-34c-5p, KCNQ1OT1 and FLJ26245 were observed to be significantly associated with the overall survival of patients with LUAD. Of note, FAM83A has potential significance in drug resistance, and may present a candidate biomarker for the prognosis and treatment of patients with LUAD.