lncRNA C22orf32-1 contributes to the tumorigenesis of nasopharyngeal carcinoma

LncRNA MIR100HG Promotes Cell Proliferation in Nasopharyngeal Carcinoma by Targeting miR-136-5p/IL-6 Axis

Nasopharyngeal carcinoma (NPC) features high mortality and poor prognosis. Additionally, long non-coding RNAs (lncRNAs) play a significant role in developing NPC and other types of cancer. But the functional mechanism of MIR100HG in NPC remains unclear. The long non-coding RNA MIR100HG messenger RNA (mRNA) expression was thoroughly evaluated in NPC tumors and adjacent tissues using quantitative polymerase chain reaction (qPCR). Furthermore, we employed Kaplan-Meier analysis to compare the expression of MIR100HG with survival outcomes. The CCK8 test was utilized to investigate the impact of the lncRNA MIR100HG/miR-136-5p/IL-6 axis on cell proliferation in NPC. The study's findings indicated overexpression of the lncRNA MIR100HG in both NPC tumors and cell lines. This upregulation was associated with a poorer outcome in individuals with NPC. When lncRNA MIR100HG was knocked down in vitro, NPC cell proliferation was inhibited, resulting in tumor suppression. In certain oncogenic capacities, the lncRNA MIR100HG functions as a competitive endogenous RNA for miR-136-5p, hence impeding the inhibitory effect of miR-136-5p on its target gene, IL-6. In summary, the findings of the present investigation suggested that lncRNA MIR100HG exhibits promising characteristics as a potential indicator for the prognosis and diagnosis of NPC.

Long Noncoding RNA GUSBP11 Knockdown Alleviates Nasopharyngeal Carcinoma via Regulating miR-1226-3p/TM9SF4 Axis

Purpose: Long noncoding RNAs (lncRNAs) have been confirmed related to the occurrence and progress of multiple cancers, including cervical cancer nasopharyngeal carcinoma (NPC). This study focused on assessing GUSBP11 effects on NPC progression and exploring possible mechanisms. Materials and Methods: RT-qPCR was conducted for assessing GUSBP11 levels within NPC tissues and cells. CCK-8, colony formation, and Transwell were adopted for examining GUSBP11 impacts on NPC cell proliferation and cell metastasis. RT-qPCR analysis and dual-luciferase reporter assay were conducted for judging the expression interrelation of GUSBP11 and its potential target miR-1226-3p. The same methods were carried out for verifying the inhibiting influences of miR-1226-3p upregulation and its potential target TM9SF4. Results: GUSBP11 levels were upregulated within NPC tissues and cells. GUSBP11 downregulation repressed NPC cell proliferation and cell metastasis. In addition, GUSBP11 targeted and negatively regulated miR-1226-3p. Furthermore, miR-1226-3p targeted TM9SF4 and mediated GUSBP11's impacts on TM9SF4 levels. At last, the authors proved the critical role of the GUSBP11/miR-1226-3p/TM9SF4 axis in regulating NPC progression. Conclusion: These findings indicate that downregulation of GUSBP11 alleviates NPC development by regulating the miR-1226-3p/TM9SF4 axis.

LINC00641 contributes to nasopharyngeal carcinoma cell malignancy through FOXD1 upregulation at the post-transcriptional level

Nasopharyngeal carcinoma (NPC) is a common tumor in the head and neck and is prevalent in China, especially in the southern regions. Molecular mechanisms have attracted much attention in NPC research. FOXD1 has been reported to be a tumor promoter in various cancers. The present study was designed to explore the function of FOXD1 in NPC cells. Functional analyses, including the trypan blue staining assay, EdU and JC-1 assay, and flow cytometry analysis, revealed that FOXD1 facilitated NPC cell proliferation and inhibited NPC cell apoptosis. Next, by means of "starBase" database and mechanism analyses, such as RIP assay, RNA pull-down assay and luciferase reporter assay, miR-378a-3p was found to target FOXD1 and negatively regulate FOXD1 expression in NPC cells. Moreover, miR-378a-3p plays a suppressive role in NPC cells. LINC00641 was identified as a sponge of miR-378a-3p and positively modulated FOXD1 expression in NPC cells. Finally, a series of rescue assays indicated that LINC00641 accelerated NPC cell proliferation and hindered NPC cell apoptosis through FOXD1 upregulation. In conclusion, the present study demonstrated an innovative ceRNA mechanism of LINC00641/miR-378a-3p/FOXD1 in NPC cells, which might provide new insights into NPC treatment.

Overexpression of Long Non-Coding RNA Linc01315 Predicts Poor Prognosis in Breast Cancer

Background

LncRNAs have been shown to play critical roles in regulating tumorigenesis and tumor progression. Using LncRNAs to predict prognosis and therapeutic response to cancer treatment has been caused for concern, but the predictive value of lncRNAs remains to be explored and underlying mechanisms have not been completely understood.

Methods

The Linc01315 expression level was detected in 282 breast cancer tissues by using quantitative RT-PCR. The association between Linc01315 expression level and clinicopathological features of these breast cancer patients was further analyzed. Multiple regression analysis was used to evaluate Linc01315 predictive value of patients’ prognosis.

Results

Our study revealed that Linc01315 expression level was significantly correlated with vessel invasion (P = 0.028) and tumor subtype (P = 0.039). The Kaplan–Meier survival curves demonstrated that patients with lower Linc01315 expression level had significantly longer disease free survival (DFS) (P = 0.002) and overall survival (OS) (P=0.019). Multiple regression analysis showed that Linc01315 level could be an independent predictive factor for DFS (hazards ratio = 0.613, 95% confidence interval = 0.375-1.003; P = 0.049) and OS (hazards ratio = 0.439, 95% confidence interval = 0.228-0.845; P = 0.014). Further analysis showed that low Linc01315 level patients with endocrine therapy could benefit patients DFS (P=0.037) and OS (P=0.025).

Conclusion

Our results demonstrate that Linc01315 expression level is significantly correlated with breast cancer patients’ prognosis. Linc01315 may represent an independent prognostic marker and therapeutic target in breast cancer.

The molecular march of primary and recurrent nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) results from the aberrant and uncontrolled growth of the nasopharyngeal epithelium. It is highly associated with the Epstein-Barr virus, especially in regions where it is endemic. In the last decade, significant advances in genetic sequencing techniques have allowed the discovery of many new abnormal molecular processes that undoubtedly contribute to the establishment, growth and spread of this deadly disease. In this review, we consider NPC as EBV induced. We summarise the recent discoveries and how they add to our understanding of the pathophysiology of NPC in the context of genomics first in primary and then in recurrent disease. Overall, we find key early events lead to p16 inactivation and cyclin D1 expression, allowing latent viral infection. Host and viral factors work together to affect a variety of molecular pathways, the most fundamental being activation of NF-κB. Nonetheless, much still yearns to be discovered, especially in recurrent NPC.

LINC01433 targets miR-506-3p to promote the biological progress of nasopharyngeal carcinoma cells

PURPOSE

The current study aimed to investigate the role of long intergenic noncoding 01433 (LINC01433) in the proliferation, migration and invasion of nasopharyngeal carcinoma (NPC).

METHODS

Real-time quantitative PCR (RT-qPCR) was performed to determine the expressions of LINC01433 and miR-506-3p in NPC samples and cell lines. The effects of LINC01433 on cell proliferation, migration and invasion were measured by CCK-8, wound healing assay and Transwell, respectively. In addition, Pearson correlation analysis, starBase, RNA immunoprecipitation, luciferase assay, Western blot and functional experiments were conducted to detect and confirm the relationship between LINC01433 and miR-506-3p.

RESULTS

LINC01433 level was noticeably elevated in NPC tissues and cell lines. As the expression of LINC01433 in 5-8F cells was the highest in NPC cell lines and the expression of LINC01433 in SUNE1 cells was the lowest, 5-8F and SUNE1 cells were therefore selected as the target cells for following experiments. Furthermore, miR-506-3p was predicted as the target of LINC01433, and the two were negatively correlated with each other. Interestingly, overexpression of LINC01433 promoted proliferation, migration and invasion of NPC cells, while miR-506-3p reversed such effects of LINC01433. Moreover, LINC01433 silencing had the opposite effects to LINC01433 overexpression. Furthermore, miR-506-3p overexpression inhibited the expressions of MMP2, N-cadherin, p-PI3K and p-Akt, and promoted the expressions of E-cadherin and TIMP-2, and partially reversed the role of LINC01433 in promoting cancer development.

CONCLUSION

The current findings reveal that LINC01433 regulates NPC cell biological progress through miR-506-3p.

LncRNA HOTTIP promotes the proliferation and invasion of ovarian cancer cells by activating the MEK/ERK pathway

Recent studies have revealed that long non-coding RNAs (lncRNAs) serve important roles in carcinogenesis and that this type of gene may be used as biomarkers in cancer. A high level of lncRNA HOXA distal transcript antisense RNA (HOTTIP) is associated with unfavorable prognosis for patients with ovarian cancer (OC), but the mechanism of HOTTIP involved in OC development remains to be elucidated. The present study aimed to investigate the mechanism of HOTTIP in metastasis-associated OC cell behaviors. HOTTIP levels in ovarian cells were quantified by reverse transcription-quantitative PCR, cell proliferation was analyzed by colony formation assay, and apoptosis was assessed by flow cytometry. Cell migratory and invasive abilities were evaluated by wound healing and Transwell assays, respectively. The expression levels of mitogen-activated protein kinase kinase (MEK)/ERK pathway-associated proteins were detected by western blotting. The results demonstrated that knockdown of HOTTIP in OC cells significantly reduced the phosphorylation levels of MEK and ERK, inhibited the proliferation and invasion of OC cells and promoted their apoptosis. Furthermore, the effects of HOTTIP on cell migration and invasion were partly associated with the epithelial-mesenchymal transition (EMT) process. Proliferation, invasion and EMT of OC cells were enhanced following overexpression of HOTTIP; however, these effects were reversed by the MEK/ERK pathway inhibitor U0126. In conclusion, HOTTIP was demonstrated to promote the proliferation, migration and invasion of OC cells by activating the MEK/ERK pathway. Therefore, HOTTIP may serve as a potential therapeutic target for OC.

Silencing of long noncoding RNA SRRM2-AS exerts suppressive effects on angiogenesis in nasopharyngeal carcinoma via activating MYLK-mediated cGMP-PKG signaling pathway

Long noncoding RNAs (lncRNAs) play a crucial role in several malignances, involving nasopharyngeal carcinoma (NPC), a heterogeneous disease. This study investigated mechanism of serine/arginine repetitive matrix protein 2-alternative splicing (SRRM2-AS) in NPC cell proliferation, differentiation, and angiogenesis. Initially, differentially expressed lncRNAs were screened out via microarray analysis. Vascular endothelial growth factor (VEGF) protein positive rate and microvessel density (MVD) were determined in NPC and adjacent tissues. NPC CNE-2 cells were treated with a series of vector and small interfering RNA to explore the effect of SRRM2-AS in NPC. The target relationship between myosin light chain kinase (MYLK) and SRRM2-AS was verified. Levels of SRRM2-AS, MYLK, cGMP, PKG, VEGF, PCNA, Ki-67, B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax), and Caspase 3 were determined after transfection. Finally, the effect of SRRM2-AS on cell proliferation, colony formation, angiogenesis, cell cycle, and apoptosis in NPC was evaluated. SRRM2-AS was highly expressed and MYLK was poorly expressed in NPC tissues. VEGF protein positive rate and MVD were elevated in NPC tissues. MYLK was confirmed to be a target gene of SRRM2-AS. Silencing of SRRM2-AS elevated levels of MYLK, cGMP, PKG, Bax, and Caspase 3, but decreased levels of VEGF, PCNA, Ki-67, and Bcl-2. Especially, silencing of SRRM2-AS suppressed cell proliferation, colony formation and angiogenesis, blocked cell cycle, and enhanced cell apoptosis in NPC. Our results suggested that silencing of SRRM2-AS protected against angiogenesis of NPC cells by upregulating MYLK and activating the cGMP-PKG signaling pathway, which provides a new target for NPC treatment.

Long Noncoding RNA HOTTIP Promotes Nasopharyngeal Cancer Cell Proliferation, Migration, and Invasion by Inhibiting miR-4301

BACKGROUND The long noncoding RNA (lncRNA) HOTTIP is involved in gastric cancer tumorigenesis, papillary thyroid carcinoma, colorectal cancer, lung adenocarcinoma, and hepatocellular carcinoma, but it is unclear how HOTTIP exerts roles in nasopharyngeal carcinoma (NPC). The present study investigated HOTTIP function during NPC development. MATERIAL AND METHODS HOTTIP levels in cancer specimens and cell lines were analyzed using qRT-PCR. HOTTIP function in NPC was determined by Cell Counting Kit-8 (CCK8) and Transwell assay. RESULTS HOTTIP expression was increased in NPC tissues. Higher levels of HOTTIP are correlated with lower survival in NPC patients. HOTTIP silencing suppressed the proliferation, cell cycle, migration, and invasion of NPC cells. HOTTIP served as a sponge for miR-4301. miR-4301 expression was significantly inhibited by HOTTIP in NPC cells. miR-4301 overexpression dramatically inhibited NPC cell proliferation, migration, and invasion. CONCLUSIONS This study showed that HOTTIP acts as an oncogene in NPC by sponging miR-4301.

The regulatory network of nasopharyngeal carcinoma metastasis with a focus on EBV, lncRNAs and miRNAs

Metastasis of nasopharyngeal carcinoma (NPC) remains a main cause of death for NPC patients even though great advances have been made in therapeutic approaches. An in-depth study into the molecular mechanisms of NPC metastasis will help us combat NPC. Epstein-Barr virus (EBV) infection is an evident feature of nonkeratinizing NPC and is strongly associated with tumor metastasis. Recently, long noncoding RNAs (lncRNAs) and microRNAs (miRNAs) have become a hot topic of research due to their epigenetic regulatory roles in NPC metastasis. The EBV products, lncRNAs and miRNAs can target each other and share several common signaling pathways, which form an interconnected, complex molecular regulatory network. In this review, we discuss the features of this regulatory network and summarize the molecular mechanisms of NPC metastasis, focusing on EBV, lncRNAs and miRNAs with updated knowledge.

MORF4L1 suppresses cell proliferation, migration and invasion by increasing p21 and E-cadherin expression in nasopharyngeal carcinoma

Mortality factor 4-like 1 (MORF4L1) is a member of a subgroup of histone acetyltransferases and belongs to the mortality factor on chromosome 4 (MORF4) class of proteins. However, the role of MORF4L1 in cancers is largely unknown. Using reverse transcription-quantitative polymerase chain reaction and published datasets, the present study demonstrated that the expression of MORF4L1 is decreased in several cancers, including nasopharyngeal carcinoma (NPC). Additionally, the methylation rate of the promoter of MORF4L1 was identified to be significantly higher in tumour cells than in normal cells. The ectopic expression of MORF4L1 was also revealed to inhibit cell proliferation, colony formation, migration and invasion in NPC, whereas the knockdown of MORF4L1 promoted cell proliferation, colony formation, migration and invasion. Mechanistically, the present study demonstrated that MORF4L1 functions as a tumour suppressor by increasing p21 and E-cadherin levels. These findings may be useful novel targets for treating patients with NPC.

LncRNA DGCR5 promotes lung adenocarcinoma (LUAD) progression via inhibiting hsa-mir-22-3p

Long non-coding RNAs (lncRNAs) serve critical roles in the pathogenesis of various cancers, including lung adenocarcinoma (LUAD). Herein, in this study, we aimed to investigate the biological and clinical significance of lncRNA DiGeorge syndrome critical region gene 5 (DGCR5) in LUAD. It was observed that DGCR5 was upregulated in LUAD tissues and LUAD cell lines. Inhibition of DGCR5 can prevent LUAD progression via playing anti-apoptosis roles. Both mRNA expression and protein levels of BCL-2 were increased by DGCR5 downregulation while reversely BAX was increased. Additionally, a novel microRNA target of DGCR5, hsa-mir-22-3p was identified through bioinformatics search and confirmed by dual-luciferase reporter system. Gain and loss-of-function studies were performed to verify whether DGCR5 exerts its biological functions through regulating hsa-mir-22-3p in vitro. Overexpression of DGCR5 was able to reverse the tumor inhibitory effect of hsa-mir-22-3p mimics. Furthermore, in vivo tests tumor xenografts were established to detect the function of DGCR5 in LUAD tumorigenesis. Downregulated DGCR5 expression was greatly associated with smaller tumor size, implying a favorable prognosis of LUAD patients. Taken these together, DGCR5 could be considered as a prognostic biomarker and therapeutic target in LUAD diagnosis and treatment.