ObjectiveTo understand the function of long non-coding RNA (lncRNA) colon cancer associated transcript-1 (CCAT1) and summarize its relationship with gastric cancer.MethodThe published literatures on the studies of lncRNA CCAT1 function and its relationship with gastric cancer were reviewed and analyzed.ResultsThe lncRNA CCAT1 exerted the negative regulation on the genes by binding to microRNAs (miR) as a competitive endogenous RNA, mediating chromatin circulation between the c-MYC promoter and its upstream enhancer, and promoted the expression of c-MYC gene. The recent studies had found that the CCAT1 could bind to the miR-219-1 and miR-490, thereby promoting the progress of gastric cancer. The expression of lncRNA CCAT1 in the gastric cancer tissues increased, which was obviously different from that in the paracancer tissues and normal tissues. The high expression of lncRNA CCAT1 was related to the tumor size, lymphatic metastasis and TNM stage.ConclusionsThe specific mechanism, intracellular signal transduction pathway and interaction mechanism between CCAT1 and other molecules involved in the progress of gastric cancer still need to be further explored. With the in-depth study of lncRNA, especially CCAT1, it may provide a broader prospect for the diagnosis and treatment of gastric cancer as a target of CCAT1.
ObjectiveTo understand the research progress of related biomarkers in early diagnosis of gastric cancer in recent years.MethodThe domestic and foregin literatures on studies of biomarkers of early diagnosis of gastric cancer in recent years were reviewed.ResultsAt present, the sensitivity and specificity of serum tumor biomarkers of gastric cancer such as CEA and CA19-9 were lower, so the molecular markers that could predict, screen, and diagnose gastric cancer in the early stage were further explored. The recent studies suggested that microRNAs, long non-coding RNAs, circular RNAs, exosome, etc. molecular markers in early diagnosis of gastric cancer had better prospects of clinilal application.ConclusionWith the continuous development of molecular biology technology, the values of microRNAs, long non-coding RNAs, circular RNAs, DNA, etc. in early diagnosis of gastric cancer would be further explored.
Objective To summarize the latest research progress of tumor energy metabolism regulated by long non-coding RNA (lncRNA). Method Literatures about the recent studies on the bioenergetic metabolic mechanisms regulated by lncRNA in tumor cells were reviewed according to the results searched from PubMed database, Springer database, HighWire database, and so on. Results Aerobic glycolysis (Warburg effect) was regarded as the most important characteristics of energy metabolism in tumor cells. lncRNA could regulate many key progressions involved energy metabolism in tumor cells, such as glucose metabolism, lipid metabolism, and glutamine metabolism, resulting in accelerated uptake of glucose, decomposition of glutamine, and formation of lipid. Conclusions The functions and mechanisms of energy metabolism in tumor cells regulated by lncRNA are entirely unclear. The role of lncRNA played in cancer needs to be understood, which may contribute to new tumor biomarker detection and effective treatment strategies.
Objective The aim of this study is to review the association between long non-coding RNA (lncRNA) and papillary thyroid carcinoma (PTC). Method The relevant literatures about lncRNA associated with PTC were retrospectively analyzed and summarized. Results The expression levels of noncoding RNA associated with MAP kinase pathway and growth arrest (NAMA), PTC susceptibility candidate 3 (PTCSC3), BRAF activated non-coding RNA (BANCR), maternally expressed gene 3 (MEG3), NONHSAT037832, and GAS8-AS1 in PTC tissues were significantly lower than those in non-thyroid carcinoma tissues. The expression levels of ENST00000537266, ENST00000426615, XLOC051122, XLOC006074, HOX transcript antisense RNA (HOTAIR), antisense noncoding RNA in the INK4 locus (ANRIL), and metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) in PTC tissues were upregulated in PTC tissues, comparing with the non-thyroid carcinoma tissues. These lncRNAs were possibly involved in cell proliferation, migration, and apoptosis of PTC. Conclusion LncRNAs may provide new insights into the molecular mechanism and gene-targeted therapy of PTC and become new molecular marker for the diagnosis of PTC.
ObjectiveTo investigate the expression level of long non-coding RNA Down’s syndrome critical region 8 (LncRNA DSCR8) in gastric cancer and its clinical significance.MethodsEighty-six patients with gastric cancer who were hospitalized in our hospital from August 2014 to August 2015 were selected as the research object. Real-time quantitative PCR (qRT-PCR) was used to detect the expression level of LncRNA DSCR8 mRNA in gastric cancer tissues and its adjacent tissues. The relationship between the expression level of LncRNA DSCR8 mRNA and clinicopathological features of gastric cancer was analyzed. Kaplan-Meier method was used to analyze the relationship between the expression of LncRNA DSCR8 mRNA and the survival rate of patients, and multivariate Cox proportional hazards regression analysis was used to analyze the prognostic factors of gastric cancer.ResultsThe expression level of LncRNA DSCR8 mRNA in gastric cancer tissues was higher than that in the paracancerous tissues (P<0.001). The expression levels of LncRNA DSCR8 mRNA in patients with poorly differentiated, TNM Ⅲ–Ⅳ and lymph node metastasis were higher than those in patients with well/moderately differentiated, TNM Ⅰ–Ⅱ and no lymph node metastasis (P<0.05). The 1, 3 and 5-year survival rate of patients with low LncRNA DSCR8 mRNA expression (97.62%, 92.86%, 83.33%, respectively) were higher than those of patients with high LncRNA DSCR8 mRNA expression (63.64%, 38.64%, 31.82%, respectively), P<0.05. LncRNA DSCR8 mRNA and TNM stage were independent risk factors of death in patients with gastric cancer (P<0.05).ConclusionsLncRNA DSCR8 is associated with the occurrence, development and prognosis of gastric cancer. It may be an important molecular marker of tumor stage and lymph node metastasis in patients with gastric cancer.
ObjectiveTo summarize the regulatory effect of long non-coding RNA (lncRNA) on osteoarthritis (OA) cartilage injury.MethodsThe molecular functions and mechanisms of lncRNA were introduced and its regulatory effects on the pathological processes of OA were elaborated by referring to the relevant literature at domestic and abroad in recent years.ResultsThe pathological characteristics of OA are degeneration of articular cartilage and inflammation of synovial tissue, but its etiology and pathological mechanism have not been clarified. lncRNA is a kind of heterogeneous non-coding RNA, which plays a regulatory role in many inflammation-related diseases and exerts a wide range of biological functions. lncRNA is a regulator involved in the pathogenesis of OA, and is abnormally expressed in OA cartilage, leading to the degeneration of the extracellular matrix of cartilage.ConclusionAt present, there have been preliminary studies on the pathological effects of lncRNA in regulating OA and the biological functions of chondrocytes. However, the pathogenesis of lncRNA and its regulatory network in OA and the way in which it regulates inflammatory pathways are still unclear, and further exploration is needed.
ObjectiveTo summarize the latest research of long non-coding RNA (lncRNA) as competitive endogenous RNA (ceRNA) and its targeting technology in pancreatic cancer, so as to provide new ideas for lncRNA targeted intervention or as an early diagnostic marker of pancreatic cancer. MethodThe domestic and foreign literature on researches of lncRNA as ceRNA and its targeting technology in the pancreatic cancer was searched and reviewed. ResultsAt present, the growing number of evidences showed that in pathological states such as tumors, the abundance of intracellular lncRNAs was sufficient to trigger ceRNA crosstalk. The lncRNA played a role like “sponge” through the complementary binding of incomplete base of miRNA with miRNA response elements, then adsorbed miRNA, and thus changed the activity and effectiveness of miRNA. It also regulated the expression of downstream target genes. Moreover, a large number of studies had identified that the lncRNA-mediated ceRNA regulatory network, namely lncRNA/miRNA/mRNA axis, played a role in promoting or inhibiting the occurrence and progression of pancreatic cancer through a variety of cellular functions. In addition, many technologies targeting lncRNA, such as small interfering RNA, antisense oligonucleotides, clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9, and small molecule inhibitors, etc. had been widely studied and acquired important results in preclinical research. ConclusionsThe ceRNA hypothesis is a functional complex composed by non-coding RNAs and mRNAs with non-coding properties, forming a ceRNA network of multi-level and cross-regulatory on the transcriptome. Epigenetic modification and key post-transcriptional regulation of lncRNA have been achieved through ceRNA network mechanism, which has become a successful paradigm for exploring the function of lncRNA. The tumor suppressive and promoting effects and mechanisms of many lncRNAs in the occurrence and development of pancreatic cancer are explored in many studies. Moreover, the continuous progress of targeted lncRNA technology provides conditions for study of lncRNA. LncRNA has a potential to be used as a biomarker for precancerous diagnosis and prognosis of pancreatic cancer.
ObjectiveA competing endogenous RNA (ceRNA) regulatory network associated with long non-coding RNA (lncRNA) specific for lung adenocarcinoma (LUAD) was constructed based on bioinformatics methods, and the functional mechanism of actinfilament-associated protein 1-antisense RNA1 (AFAP1-AS1) in LUAD was analyzed, in order to provide a new direction for the study of LUAD therapeutic targets. MethodsThe gene chip of LUAD was downloaded from the Gene Expression Omnibus (GEO), and lncRNA and mRNA with differential expression between LUAD and normal tissues were screened using GEO2R online software, and their target genes were predicted by online databases to construct ceRNA networks and perform enrichment analysis. In cell experiments, AFAP1-AS1 was genetically knocked down and siRNA was constructed and transfected into LUAD cells A549 by cell transfection. CCK8, transwell, scratch assay and flow cytometry were used to detect the ability of cells to proliferate, invade, migrate and apoptosis. ResultsA total of 6 differentially expressed lncRNA and 494 differentially expressed mRNA were identified in the microarray of LUAD. The ceRNA network involved a total of 6 lncRNA, 22 miRNA, and 55 mRNA. Enrichment analysis revealed that mRNA was associated with cancer-related pathways. In cell assays, knockdown of AFAP1-AS1 inhibited cell proliferation, invasion, and migration, and AFAP1-AS1 promoted apoptosis. ConclusionIn this study, we construct a lncRNA-mediated ceRNA network, which may help to further investigate the mechanism of action of LUAD. In addition, through cellular experiments, AFAP1-AS1 is found to have potential as a therapeutic target for LUAD.
Objective To investigate the role of long non-coding RNA metastasis-associated in colon cancer 1-antisense RNA （MACC1-AS1）in cisplatin resistant gastric cancer and its possible mechanism. Methods Human gastric cancer cell line BGC823 and cisplatin resistant gastric cancer cell line (BGC823/DDP) were selected as the research objects. BGC823/DDP cells were transfected and divided into negative control group (si-NC group, transfected with si-NC empty plasmid) and MACC1-AS1 gene silencing group (si-MACC1-AS1 group, transfected with si-MACC1-AS1 plasmid). The BGC823 cells were transfected and divided into positive control group (pcDNA-NC group, transfected with pcDNA-NC empty plasmid) and MACC1-AS1 gene overexpression group (pcDNA-MACC1-AS1 group, transfected with pcDNA-MACC1-AS1 plasmid). MTT was used to detect the inhibition and 50% inhibition concentration (IC50). Flow cytometry was used to detect apoptosis. Real-time fluorescence quantitative PCR was used to detect the mRNA expression levels of MACC1-AS1, B-lymphoma-2 gene (Bcl-2), Bcl-2 related X gene (Bax), mammalian target of rapamycin (mTOR), phosphorylated mTOR (p-mTOR), protein kinase B (AKT), and phosphorylated AKT (p-AKT). Western blot was used to detect the protein expression levels of Bax, Bcl-2, p-mTOR, mTOR, AKT, and p-AKT. Results The relative expression level of MACC1-AS1 mRNA in BGC823/DDP cells was higher than that in BGC823 gastric cancer cells (P<0.01). The relative expression level of MACC1-AS1 mRNA in the si-MACC1-AS1 group cells was lower than that in the si-NC group cells (P<0.01). The relative expression level of MACC1-AS1 mRNA in the pcDNA-MACC1-AS1 group cells was higher than that in the pcDNA-NC group cells (P<0.01). The cell growth inhibition rate and IC50 of the si-MACC1-AS1 group were higher than those of the si-NC group (P<0.01). The cell growth inhibition rate and IC50 of the pcDNA-MACC1-AS1 group were lower than those of the pcDNA-NC group (P<0.01). The mRNA and protein relative expression levels of Bcl-2, p-AKT/AKT and p-mTOR/mTOR in the pcDNA-MACC1-AS1 group were significantly higher than those in the pcDNA-NC group (P<0.01). The relative expression levels of Bax protein and mRNA in the pcDNA-MACC1-AS1 group were significantly lower than those in the pcDNA-NC group (P<0.01). The apoptosis rate of the pcDNA-MACC1-AS1 group was significantly lower than that of the pcDNA-NC group (P<0.01). The mRNA and protein relative expression levels of Bcl-2, p-AKT/AKT and p-mTOR/mTOR in the si-MACC1-AS1 group were significantly lower than those in the si-NC group (P<0.01). The relative expression levels of Bax protein and mRNA in the si-MACC1-AS1 group were significantly higher than those in the si-NC group (P<0.01). The apoptosis rate of the si-MACC1-AS1 group was significantly higher than that of the si-NC group (P<0.01). Conclusions MACC1-AS1 highly expresses in cisplatin resistant gastric cancer cells. Overexpression of MACC1-AS1 regulates AKT/mTOR pathway mediated apoptosis and enhances cisplatin resistance of gastric cancer cells.
ObjectiveCombined with long non-coding RNA (lncRNA) to find a regression model that can be used to predict the survival rate of patients with colon cancer before operation.MethodsThe clinical information and gene expression information of patients with colon cancer were downloaded by using TCGA database. The differentially expressed lncRNAs in tumor and paracancerous tissues were screened out, and then combined with the clinical information of patients to construct Cox proportional hazard regression model.ResultsA total of 26 kinds of lncRNAs with statistical difference in gene expression between paracancerous tissues and tumor tissues were selected (P<0.05). Through repeated screening and comparison of prediction efficiency, the prediction model was finally selected, which was constructed by patients’ age, M stage, N stage, and three kinds of lncRNAs (ZFAS1, SNHG25, and SNHG7) gene expression level: age [HR=4.00, 95%CI: (1.48, 10.84), P=0.006], M stage [HR=3.96, 95%CI: (2.23, 7.04), P<0.001], N stage [HR=1.87, 95%CI: (1.24, 2.84), P=0.003], ZFAS1 gene expression level [HR=0.60, 95%CI: (0.41, 0.86), P=0.006], SNHG25 gene expression level [HR=0.85, 95%CI: (0.73, 1.00), P=0.045], and SNHG7 gene expression level [HR=2.32, 95%CI: (1.53, 3.52), P<0.001] were all independent risk factors for postoperative survival of patients with colon cancer. The area under the ROC curves for predicting 1, 3, and 5-year overall survival were 0.802, 0.828, and 0.771, respectiely, which had a good prediction ability.ConclusionThe predictive model constructed by the combination of ZFAS1, SNHG25, SNHG7 genes expression level with M stage, N stage, and age can better predict the overall survival rate of patients before operation, which can effectively guide clinical decision-making and choose the most suitable treatment method for patients.