Long non-coding RNA OIP5-AS1 promotes proliferation of lung cancer cells and leads to poor prognosis by targeting miR-378a-3p

LncRNA OIP5-AS1 interacts with miR-363-3p to contribute to hepatocellular carcinoma progression through up-regulation of SOX4

Long noncoding RNA OIP5-AS1 has been observed to be increased in several cancers, however, its role and biological mechanism was poorly understood in HCC. Currently, we found OIP5-AS1 expression was upregulated in HCC cells compared with normal human liver cells. Knockdown of OIP5-AS1 suppressed HCC cell proliferation, induced cells cycle arrest and cells apoptosis. In addition, HCC cell migration and invasion capacity in vitro were also inhibited by OIP5-AS1 inhibition. Bioinformatics analysis revealed OIP5-AS1 could interact with miR-363-3p, thereby repressing HCC development. We also observed miR-363-3p was significantly decreased in HCC cells and overexpression of miR-363-3p repressed HCC progression. The correlation between OIP5-AS1 and miR-363-3p was confirmed by performing RIP assay and RNA pull-down assay. Subsequently, SOX4 was predicted as a target of miR-363-3p and miR-363-3p modulated SOX4 levels negatively in vitro. Apart from these, in vivo experiments established that OIP5-AS1 can suppress HCC development through regulating miR-363-3p and SOX4. Collectively, these demonstrated that OIP5-AS1 was involved in HCC progression via targeting miR-363-3p and SOX4. OIP5-AS1 can act as a novel candidate for HCC diagnosis, prognosis, and therapy.

Long non-coding RNA OIP5-AS1 serves as an oncogene in laryngeal squamous cell carcinoma by regulating miR-204-5p/ZEB1 axis

Laryngeal squamous cell carcinoma (LSCC) is the most common type of laryngeal cancer with poor prognosis. In the present study, we aimed to investigate the biological role of long non-coding RNA OIP5-AS1 in LSCC. The results demonstrated that the expression levels of OIP5-AS1 were significantly increased in LSCC tissues and cell lines. High expression of OIP5-AS1 was closely correlated with lymph node metastasis and advanced clinical stage of LSCC patients. Moreover, in vitro assays showed that OIP5-AS1 overexpression promoted the proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) of LSCC cells, whereas OIP5-AS1 knockdown exerted suppressive effects on LSCC cells. Furthermore, OIP5-AS1 was confirmed to serve as a competing endogenous RNA of miR-204-5p in LSCC cells, and restoration of miR-204-5p counteracted the OIP5-AS1-mediated oncogenic effects. In conclusion, our study provides promising evidence that lncRNA OIP5-AS1 functions as a tumor promoter in LSCC and may be used as a potential target for LSCC therapy.

Long non-coding RNAs as the critical factors during tumor progressions among Iranian population: an overview

BACKGROUND

Cancer is associated with various genetic and environmental risk factors. Beside the mutations or aberrant expression of protein-coding genes, the genetic deregulation of non-coding RNAs has also an important role during tumor progression and metastasis. Long non-coding RNAs (lncRNAs) are a class of ncRNAs larger than 200 nucleotides that may function as tumor-suppressor or oncogene.

MAIN BODY

There is a raising trend of cancer incidence among Iranian population during the last decades. Therefore, it is required to prepare a general population specific panel of genetic markers for the early detection of cancer in this population. The tissue-specific expression characteristics and high stability in body fluids highlight the lncRNAs as efficient diagnostic and prognostic noninvasive biomarkers in cancer. In present review we summarized all of the lncRNAs which have been reported until now in different tumors among Iranian patients.

CONCLUSIONS

This review paves the way of introducing a population based noninvasive diagnostic panel of lncRNAs for the early detection of tumor cells among Iranian population.

lncRNA OIP5-AS1 targets ROCK1 to promote cell proliferation and inhibit cell apoptosis through a mechanism involving miR-143-3p in cervical cancer

Opa-interacting protein 5 antisense transcript 1 (OIP5-AS1) is one kind of cytoplasmic long non-coding RNA (lncRNA), which has been demonstrated to play a critical function in multiple cancers. However, the detailed mechanism of OIP5-AS1 in the regulation of cervical cancer progression is still obscure. Here, we demonstrated that lncRNA OIP5-AS1 was upregulated in cervical cancer and was correlated with poor prognosis by bioinformatics studies. OIP5-AS1 depletion inhibited cell proliferation and promoted cell apoptosis in cervical cancer cells. Furthermore, we clarified that ROCK1 was the downstream effector of OIP5-AS1 and OIP5-AS1 acted as a molecular sponge of miR-143-3p. Finally, we verified that OIP5-AS1 exerted its function in the regulation of cervical cancer progression via interacting with miR-143-3p to regulate ROCK1 expression. Our study revealed novel mechanisms about how lncRNA OIP5-AS1 executed its function in cervical cancer and thus provided potential therapeutic targets for the disease.

Upregulation of OIP5-AS1 Predicts Poor Prognosis and Contributes to Thyroid Cancer Cell Proliferation and Migration

As a common malignancy, thyroid cancer mainly occurs in the endocrine system. There have been accumulating studies on therapeutic methods of thyroid cancer, but its internal molecular mechanism is still not fully understood. Long noncoding RNA (lncRNA) OIP5-AS1 was confirmed as an oncogene and related to poor prognosis in various cancers. Nevertheless, its role and underlying mechanism remain unclear in thyroid cancer. Here, we observed a significant upregulation of OIP5-AS1 in thyroid cancer tissues and cells, and upregulated OIP5-AS1 was correlated with poor prognosis in thyroid cancer. Moreover, OIP5-AS1 knockdown resulted in the inhibited cell proliferation and migration, while overexpressed OIP5-AS1 exhibited the reverse function in thyroid cancer. Besides, OIP5-AS1 was found to positively regulate Wnt/β-catenin signaling pathway. Through mechanism exploration, OIP5-AS1 was discovered to activate Wnt/β-catenin signaling pathway via FXR1/YY1/CTNNB1 axis. Finally, rescue assays indicated that the inhibitive role of silenced OIP5-AS1 in thyroid cancer cell growth and Wnt/β-catenin signaling pathway could be rescued by overexpression of CTNNB1 or addition of lithium chloride (LiCl). In conclusion, upregulation of OIP5-AS1 predicted unfavorable prognosis and enhanced thyroid cancer cell growth by activating Wnt/β-catenin signaling pathway.

Bioinformatics analysis of LINC00426 expression in lung cancer and its correlation with patients' prognosis

BACKGROUND

To investigate the expression of long noncoding RNA (lncRNA) LINC00426 (long intergenic nonprotein coding RNA 426) in non-small cell lung cancer (NSCLC) patients and its correlation with their prognosis.

METHODS

The expression of long noncoding RNA LINC00426 of non-small cell lung cancer (NSCLC) in The Cancer Genome Atlas (TCGA) database was screened. According to the expression level of LINC00426 in tumor tissue of NSCLC patients, the patients were divided into high and low LINC00426 expression groups. The correlation between LINC00426 expression group and the prognosis of the patient was analyzed by log-rank test. A total of 72 NSCLC patients who had undergone surgery were retrospectively included in this study. LINC00426 relative expression of tumor and normal lung tissue of the included 72 NSCLC patients were examined by real-time quantitative PCR assay. The correlation between LINC00426 expression and the patients' clinical characteristics were also evaluated.

RESULTS

LINC00426 relative expression was not statistically different between cancer and normal tissue (P > 0.05) of NSCLC patients in the TCGA database. The amplification and deep deletion mutation of LINC00426 gene was found in 0.5% of NSCLC patients. The overall survival (OS) of the LINC00426 high expression group was significantly higher than that of the low expression group (HR = 0.81, P = 0.044), while there was no significant difference between the high and low expression group (HR = 0.97, P = 0.82) for disease-free survival (DFS). LINC0042646 expression level was elevated in 46 cases in normal lung tissue compared to the tumor tissue of the 72 NSCLC patients. LINC0042646 expression level was significantly correlated with the clinical stage (P < 0.05).

CONCLUSION

Long noncoding RNA LINC00426 was downregulated in the tumor tissue of NSCLC patients and correlated with poor prognosis.

Long noncoding RNA OIP5-AS1 acts as a competing endogenous RNA to promote glutamine catabolism and malignant melanoma growth by sponging miR-217

The long noncoding RNA (lncRNA) OIP5-AS1 has been considered to promote the growth and metastasis of many human tumors. However, the role of OIP5-AS1 in melanoma has not been reported. In this study, we found that OIP5-AS1 levels were significantly elevated in melanoma tissue and that high OIP5-AS1 expression was an independent risk factor for the poor survival of patients with melanoma. miR-217 suppressed glutamine catabolism in melanoma cells by targeting glutaminase (GLS), the rate-limiting enzyme of glutamine catabolism. We also demonstrated that OIP5-AS1 acted as a sponge of miR-217 to upregulate GLS expression, thus promoting glutamine catabolism and melanoma growth. Overall, this result elucidates a new mechanism for OIP5-AS1 in metabolism in melanoma and provides a potential therapeutic target for patients with melanoma.

Long noncoding RNA OIP5-AS1 in cancer

Long noncoding RNAs (lncRNAs) can be over two hundred nucleotides in length and lack an obvious open reading frame (ORF). Interestingly, these RNAs form a group of nucleic acids involved in a variety of diverse cellular mechanisms involving proliferation, differentiation, apoptosis,and senescence. Given these characteristics, it is not unexpected that the aberrant expression of certain lncRNAs is strongly linked to oncogenesis and tumor advancement. OIP5-AS1, a prominent tumor-associated lncRNA, contributes to intricate cellular mechanisms during the evolution of malignant tumors. For example, it not only represses cyclin G-associated kinase (GAK) expression thus impacting mitosis, but also regulates cell proliferation and apoptosis in many cancers, including lung adenocarcinoma, breast, glioma and hepatoblastoma. In this paper, we review our current understanding of OIP5-AS1 in carcinogenesis and its potential application as a clinical biomarker or therapeutic target in malignancy.

LINC81507 act as a competing endogenous RNA of miR-199b-5p to facilitate NSCLC proliferation and metastasis via regulating the CAV1/STAT3 pathway

Lung cancer is the leading cause of cancer-related mortality worldwide. Recently, accumulating data indicate that long noncoding RNAs (LncRNAs) function as novel crucial regulators of diverse biological processes, including proliferation and metastasis, in tumorigenesis. Lnc NONHSAT081507.1 (LINC81507) is associated with lung adenocarcinoma. However, its pathological role in non-small cell lung cancer (NSCLC) remains unknown. In our study we investigated the role of LINC81507 in NSCLC. The expression of LINC81507 was analyzed in 105 paired NSCLC tumor specimens and paired adjacent non-tumorous tissues from NSCLC patients by real-time quantitative PCR (RT-qPCR). Gain- and loss-of-function experiments were conducted to investigate the functions of LINC81507, miR-199b-5p and CAV1. Reduced expression of LINC81507 resulted in cell growth, proliferation, migration and epithelial–mesenchymal transition (EMT) in NSCLC cells, whereas ectopic overexpression of LINC81507 resulted in the opposite effects both in vitro and in vivo. Nuclear and Cytoplasmic fractionation assays showed LINC81507 mainly resided in cytoplasm. Bioinformatics analysis and dual-luciferase assays revealed that miR-199b-5p was a direct target of LINC81507 through binding Ago2. Mechanistic analysis demonstrated that miR-199b-5p specifically targeted the Caveolin1 (CAV1) gene, and LINC81507 inactivated the STAT3 pathway in a CAV1-dependent manner. Taken together, LINC81507 is decreased in NSCLC and functions as a sponge to miR-199b-5p to regulate CAV1/STAT3 pathway, which suggests that LINC81507 serve as a tumor suppressor and potential therapeutic target and biomarker for metastasis and prognosis in NSCLC.

Increased expression of lncRNA FTH1P3 predicts a poor prognosis and promotes aggressive phenotypes of laryngeal squamous cell carcinoma

Laryngeal squamous cell cancer (LSCC) is a highly aggressive malignancy in the head and neck region. Recent studies have shown that long noncoding RNAs (lncRNAs) are novel transcripts that play an important role in the progression of LSCC. However, the overall pathophysiological regulation of lncRNAs to LSCC is largely unknown. The present study aimed to determine the clinical significances of lncRNA ferritin heavy chain 1 pseudogene 3 (FTH1P3) and to identify its potential roles in LSCC. Quantitative real-time PCR (qRT-PCR) showed that FTH1P3 expression was significantly up-regulated in LSCC tissues than that in non-neoplastic tissues. High FTH1P3 expression was positively correlated with the poor differentiation, high T classification, positive lymph node metastasis, and advanced clinical stage. Overall survival analysis showed that high levels of FTH1P3 predicted a poor prognosis in LSCC patients. Moreover, elevated expression of FTH1P3 was found to increase LSCC cell proliferation, migration and invasion, and to inhibit cell apoptosis, Conversely, knockdown of FTH1P3 suppressed LSCC cell proliferation, migration and invasion, and induced cell apoptosis. In addition, overexpression of FTH1P3 resulted in an increase in cells in S phase and a decrease in cells in G0/G1 phase, whereas inhibition of FTH1P3 did the opposite effects. Taken together, these results suggested that increased expression of FTH1P3 predicts a poor prognosis and promotes aggressive phenotypes of LSCC by regulating cell proliferation, migration, invasion, apoptosis, and cell cycle, indicating FTH1P3 may serve as a promising therapeutic biomarker for the treatment of LSCC.

Circle RNA hsa_circRNA_100290 serves as a ceRNA for miR-378a to regulate oral squamous cell carcinoma cells growth via Glucose transporter-1 (GLUT1) and glycolysis

Aerobic glycolysis (the Warburg effect) is a robust metabolic hallmark of most tumors, including oral squamous cell carcinoma (OSCC). Glucose transporter 1 (GLUT1), a major glucose transporter regulating the glucose uptake, is upregulated in OSCC and participated in the cell glycolysis of OSCC. The deregulation and function of noncoding RNAs in cancers have been widely reported. Reportedly, hsa_circular RNA (circRNA)_100290 (circ_SLC30A7) is significantly upregulated (fold change = 6.91, p < 0.0000001) in OSCC. According to online tools prediction (miRWalk, miRanda, and Targetscan), miR-378a could simultaneously target circRNA_100290 and GLUT1. Herein, the expression of circRNA_100290 and GLUT1 remarkably increased in oral tumor tissue specimens and cells. In OSCC cell lines, cell proliferation and glycolysis could be remarkably downregulated by circRNA_100290 silence, which could be rescued by GLUT1 overexpression. Conversely, miR-378a expression could be remarkably inhibited in tumor tissue specimens and cells. The effect of miR-378a overexpression on OSCC cells was similar to those of circRNA_100290 silence. miR-378a directly bound to circRNA_100290 and GLUT1 3'-untranslated region, circRNA_100290 could remarkably relieve miR-378a-induced inhibition on GLUT1 via acting as a competing endogenous RNA (ceRNA). miR-378a inhibition remarkably attenuated the effect of circRNA_100290 silence on cell proliferation and glycolysis in OSCC cell lines. In summary, circRNA_100290 serves as a ceRNA to counteract miR-378a-mediated GLUT1 suppression, thus promoting glycolysis and cell proliferation in OSCC. We provide a reliable experimental basis for understanding the mechanism of cell growth and glycolysis deregulation in OSCC.

LncRNA OIP5-AS1 predicts poor prognosis and regulates cell proliferation and apoptosis in bladder cancer

Opa-interacting protein 5 antisense RNA 1 (OIP5-AS1) is a long intergenic noncoding RNA, which has been suggested to be dysregulated in human cancers and served as tumor suppressor or promoter depending on tumor types. However, the role of OIP5-AS1 in bladder cancer was still unknown. In our study, OIP5-AS1 was overexpressed in bladder cancer, and associated with clinical progression and short overall survival. The loss-of-function studies suggested downregulation of OIP5-AS1 expression decreased cell viability, induced cell-cycle arrest and promoted cell apoptosis in bladder cancer. There was a positive association between OIP5-AS1 expression and OIP5 expression in bladder cancer tissues. Moreover, downregulation of OIP5-AS1 expression reduced messenger RNA and protein levels of OIP5 in bladder cancer cell lines. In conclusion, OIP5-AS1 is a useful biomarker for predicting clinical progression and poor prognosis and promotes cell proliferation through modulating OIP5 expression.