LINC00114 promoted nasopharyngeal carcinoma progression and radioresistance in vitro and in vivo through regulating ERK/JNK signaling pathway via targeting miR-203

LncRNAs as biomarkers for predicting radioresistance and survival in cancer: a meta-analysis

The effect of long noncoding RNAs (lncRNAs) on the radiotherapy response has been gradually revealed. This systematic review and meta-analysis aimed to evaluate the association between the function and underlying mechanism of lncRNAs in regulating the radiosensitivity and radioresistance of different tumors. Hazard ratios (HRs) with corresponding 95% confidence intervals (CIs) were calculated to estimate the effect of lncRNAs on cancer patient prognosis, including overall survival (OS), recurrence-free survival (RFS), disease-free survival (DFS) and progression-free survival (PFS). Collectively, 23 lncRNAs in 11 cancer types were enrolled. Of them, 13 lncRNAs were downregulated and related to radiosensitivity, 11 lncRNAs were upregulated and related to radioresistance, and 3 lncRNAs were upregulated and related to radiosensitivity in cancers. Furthermore, 17 microRNAs and 20 pathways were targeted by different lncRNAs and contributed to the cancer radiotherapy response in this meta-analysis. The individual pooled HRs (95% CIs) of downregulated radiation-resistant and upregulated radiation-resistant lncRNAs for OS were 0.49 (0.40-0.60) and 1.88 (1.26-2.79), respectively. Our results showed that lncRNAs could modulate tumor radioresistance or sensitivity by affecting radiation-related signaling pathways and serve as potential biomarkers to predict radiotherapy response.

The Mechanism of Long Non-coding RNA in Cancer Radioresistance/Radiosensitivity: A Systematic Review

Background and purpose: Radioresistance remains a significant challenge in tumor therapy. This systematic review aims to demonstrate the role of long non-coding RNA (lncRNA) in cancer radioresistance/radiosensitivity.

Material and methods: The electronic databases Pubmed, Embase, and Google Scholar were searched from January 2000 to December 2021 to identify studies addressing the mechanisms of lncRNAs in tumor radioresistance/sensitivity, each of which required both in vivo and in vitro experiments.

Results: Among the 87 studies identified, lncRNAs were implicated in tumor radioresistance/sensitivity mainly in three paradigms. 1) lncRNAs act on microRNA (miRNA) by means of a sponge, and their downstream signals include some specific molecular biological processes (DNA repair and chromosome stabilization, mRNA or protein stabilization, cell cycle and proliferation, apoptosis-related pathways, autophagy-related pathways, epithelial-mesenchymal transition (EMT), cellular energy metabolism) and some signaling mediators (transcription factors, kinases, some important signal transduction pathways) that regulate various biological processes. 2) lncRNAs directly interact with proteins, affecting the cell cycle and autophagy to contribute to tumor radioresistance. 3) lncRNAs act like transcription factors to initiate downstream signaling pathways and participate in tumor radioresistance.

Conclusion: lncRNAs are important regulators involved in tumor radioresistance\sensitivity. Different lncRNAs may participate in the radioresistance with the same regulatory paradigm, and the same lncRNAs may also participate in the radioresistance in different ways. Future research should focus more on comprehensively characterizing the mechanisms of lncRNAs in tumor radioresistance to help us identify corresponding novel biomarkers and develop new lncRNA-based methods to improve radioresistance.

MIR600HG sponges miR-125a-5p to regulate glycometabolism and cisplatin resistance of oral squamous cell carcinoma cells via mediating RNF44

There is increasing evidence that dysregulated long non-coding RNA (lncRNA) is implicated in tumorigenesis and progression. We aim to explore the role of lncRNA MIR600HG in glycometabolism and cisplatin (DDP) resistance of oral squamous cell carcinoma (OSCC) cells via regulating microRNA-125a-5p (miR-125a-5p) and RING finger 44 (RNF44). Expression of MIR600HG, miR-125a-5p, and RNF44 in OSCC clinical samples, cell lines, and DDP-resistant OSCC cells (SCC-9/DDP) was determined. In SCC-9 cells, proliferation, IC50 value of DDP, migration, invasion, and apoptosis were detected; in SCC-9/DDP cells, proliferation, IC50 value of DDP, apoptosis, glucose consumption, and production of lactic acid and ATP were evaluated. The interaction of MR600HG, miR-125a-5p, and RNF44 was verified. MIR600HG and RNF44 were upregulated while miR-125a-5p was downregulated in OSCC tissues and cell lines, and also in SCC-9/DDP cells. In SCC-9 cells, MIR600HG overexpression improved cell growth, metastasis, and inhibited cell susceptibility to DDP; in SCC-9/DDP cells, silencing of MIR600HG promoted apoptosis, improved DDP sensitivity, and inhibited cell glycolysis. Downregulation of miR-125a-5p showed the opposite effect to downregulation of MIR600HG. MIR600HG bound to miR-125a-5p and miR-125a-5p targeted RNF44. Downregulation of miR-125a-5p reversed the improvement of DDP sensitivity and the inhibition of cell glycolysis by downregulated MIR600HG on SCC-9/DDP cells. Downregulating RNF44 reversed the promotion of DDP resistance and cell glycolysis of SCC-9/DDP cells mediated by downregulation of miR-125a-5p. Collectively, our study addresses that MIR600HG downregulation elevates miR-125a-5p and reduces RNF44 expression, thereby improving DDP sensitivity and inhibiting glycolysis in DDP-resistant OSCC cells.

LINC00114 stimulates growth and glycolysis of esophageal cancer cells by recruiting EZH2 to enhance H3K27me3 of DLC1

Objective

LINC00114 could promote the development of colorectal cancer, but its mechanism has been rarely discussed in esophageal cancer (EC). Herein, we explored the molecular mechanism of LINC00114 via mediating enhancer of zeste homolog 2/deleted in liver cancer 1 (EZH2/DLC1) axis in EC.

Methods

LINC00114, EZH2 and DLC1 expression in EC tissues and cells were tested. LINC00114, EZH2 and DLC1 expression were altered in EC cells through transfection with different constructs, and cell proliferation, migration, invasion, apoptosis and glycolysis were subsequently observed. The interaction between LINC00114 and EZH2 and that between EZH2 and DLC1 were explored. Tumor formation was also conducted to confirm the in vitro results.

Results

The expression levels of LINC00114 and EZH2 were elevated while those of DLC1 were reduced in EC. Inhibiting LINC00114 or reducing EZH2 blocked cell proliferation, migration, invasion and glycolysis and induce cell apoptosis in EC. LINC00114 promoted H3K27 trimethylation of DLC1 by recruiting EZH2. Knockdown of DLC1 stimulated cell growth and glycolysis in EC and even mitigated the role of LINC00114 inhibition in EC. In vivo experiment further confirmed the anti-tumor effect of LINC00114 inhibition in EC.

Conclusion

The data indicate that LINC00114 promotes the development of EC by recruiting EZH2 to enhance H3K27me3 of DLC1.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13148-022-01258-y.

Involvement of Non-Coding RNAs in Chemo- and Radioresistance of Nasopharyngeal Carcinoma

The crucial treatment for nasopharyngeal carcinoma (NPC) is radiation therapy supplemented by chemotherapy. However, long-term radiation therapy can cause some genetic and proteomic changes to produce radiation resistance, leading to tumour recurrence and poor prognosis. Therefore, the search for new markers that can overcome the resistance of tumor cells to drugs and radiotherapy and improve the sensitivity of tumor cells to drugs and radiotherapy is one of the most important goals of pharmacogenomics and cancer research, which is important for predicting treatment response and prognosis. Non-coding RNAs (ncRNAs), such as microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), may play important roles in regulating chemo- and radiation resistance in nasopharyngeal carcinoma by controlling the cell cycle, proliferation, apoptosis, and DNA damage repair, as well as other signalling pathways. Recent research has suggested that selective modulation of ncRNA activity can improve the response to chemotherapy and radiotherapy, providing an innovative antitumour approach based on ncRNA-related gene therapy. Therefore, ncRNAs can serve as biomarkers for tumour prediction and prognosis, play a role in overcoming drug resistance and radiation resistance in NPC, and can also serve as targets for developing new therapeutic strategies. In this review, we discuss the involvement of ncRNAs in chemotherapy and radiation resistance in NPC. The effects of these molecules on predicting therapeutic cancer are highlighted.

A Novel Signature Constructed by Immune-Related LncRNA Predicts the Immune Landscape of Colorectal Cancer

Colorectal cancer (CRC) has the characteristics of high morbidity and mortality. LncRNA not only participates in the progression of CRC through genes and transcription levels, but also regulates the tumor microenvironment and leads to the malignant phenotype of tumors. Therefore, we identified immune-related LncRNAs for the construction of clinical prognostic model. We searched The Cancer Genome Atlas (TCGA) database for original data. Then we identified differentially expressed irlncRNA (DEirlncRNA), which was paired and verified subsequently. Next, univariate analysis, Lasso and Cox regression analysis were performed on the DEirlncRNA pair. The ROC curve of the signature was drawn, and the optimal cut-off value was found. Then the cohort was divided into a high-risk and a low-risk group. Finally, we re-evaluated the signature from different perspectives. A total of 16 pairs of DEirlncRNA were included in the construction of the model. After regrouping according to the cut-off value of 1.275, the high-risk group showed adverse survival outcomes, progressive clinicopathological features, specific immune cell infiltration status, and high sensitivity to some chemotherapy drugs. In conclusion, we constructed a signature composed of immune-related LncRNA pair with no requirement of the specific expression level of genes, which shows promising clinical predictive value in CRC patients.

Long non-coding RNA TUG1 aggravates cerebral ischemia and reperfusion injury by sponging miR-493-3p/miR-410-3p

Background

Cerebral ischemia and reperfusion injury (CIRI) affects bodily function by causing irreversible damage to brain cells. The diverse pathophysiological course factors hinder the research work to go deeper. Long noncoding RNA taurine-upregulated gene 1 (TUG1) has been reported to be related to CIRI. This study explored the undefined regulatory pathway of TUG1 in CIRI.

Methods

Quantitative real-time polymerase chain reaction was applied to test the expression of TUG1, microRNA (miR)-493-3p and miR-410-3p. The viability and apoptosis of oxygen and glucose deprivation/reoxygen (OGD/R) model cells were evaluated by cell counting kit-8 and flow cytometry assay, respectively. The determination of inflammatory factors of interleukin-6, interleukin-1β and tumor necrosis factor-α was presented by enzyme-linked immunosorbent assay. The oxidative stress was performed by measuring the generation of malondialdehyde, reactive oxygen species and the activity of superoxide dismutase. Cytotoxicity was presented by measuring the generation of lactate dehydrogenase. Western blot assay was devoted to assessing the level of apoptosis-related factors (cleaved-caspase-3 and cleaved-caspase-9) and the protein level of c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38 MAPK) pathway-related factors in neuro-2a cells treated by OGD/R. Besides, online database starBase was applied to predict the potential binding sites of TUG1 to miR-493-3p and miR-410-3p, which was further confirmed by the dual-luciferase reporter system.

Results

The expression of TUG1 was upregulated, while miR-493-3p or miR-410-3p was downregulated in the serum of CIRI and OGD/R model cells. Meanwhile, knockdown of TUG1 eliminated the suppression in proliferation, the promotion in apoptosis, inflammation and oxidative stress, as well as the cytotoxicity in OGD/R model cells. Interestingly, the inhibition of miR-493-3p or miR-410-3p allayed the above effects. In addition, TUG1 harbored miR-493-3p or miR-410-3p and negatively regulated their expression. Finally, the TUG1 activated JNK and p38 MAPK pathways by sponging miR-493-3p/miR-410-3p.

Conclusion

TUG1 motivated the development of CIRI by sponging miR-493-3p/miR-410-3p to activate JNK and p38 pathways. The novel role of TUG1 in CIRI may contribute to the advancement of CIRI treatment.

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.

Galectin‑3 facilitates the proliferation and migration of nasopharyngeal carcinoma cells via activation of the ERK1/2 and Akt signaling pathways, and is positively correlated with the inflammatory state of nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is an epithelial carcinoma originating from the nasopharyngeal mucosal tissue and is highly prevalent in southeast Asia. Galectin-3 (gal-3) serves crucial roles in many cancers but its role in NPC remains to be elucidated. The aim of the present study was to investigate the role of gal-3 in NPC. Immunohistochemistry and ELISA were used to determine the expression level of gal-3 in patients with NPC or chronic rhinitis (CR). Gal-3 short hairpin (sh)RNA was established to knockdown gal-3 in 5–8F and 6–10B cells, allowing for the evaluation of the roles of gal-3 in proliferation, migration and apoptosis in NPC cell lines. Immunohistochemistry staining of IL-6 and IL-8 was applied to access the inflammatory state of tumor tissues, and the correlation between the inflammatory state and gal-3 was analyzed. The results demonstrated that gal-3 was upregulated in patients with NPC compared with patients with CR. Knockdown of gal-3 inhibited proliferation and migration in 5-8F and 6-10B cells, as well as promoted apoptosis in these cells. The expression levels of MMP-9 and IL-8 were also decreased in 5-8F and 6-10B cells after transfection with gal-3 shRNA. A positive correlation was identified between the expression level of gal-3 and the inflammatory state of NPC. The phosphorylation levels of ERK1/2 and Akt were downregulated after knockdown of gal-3 in 5-8F and 6-10B cells. In conclusion, the expression level of gal-3 was upregulated in patients with NPC and was positively correlated with the inflammatory state of NPC. The results suggested that gal-3 promoted the proliferation and migration of 5-8F and 6-10B cells, while inhibiting the apoptosis of these cells. Moreover, activation of ERK1/2 and Akt may be the underlying mechanism of the effects of gal-3 on NPC.