Study on the Role and Mechanism of METTL3 Mediating the Up-regulation of m6A Modified Long Non-coding RNA THAP7-AS1 in Promoting the Occurrence of Lung Cancer / 中国肺癌杂志

BACKGROUND@#Lung cancer is a major threat to human health. The molecular mechanisms related to the occurrence and development of lung cancer are complex and poorly known. Exploring molecular markers related to the development of lung cancer is helpful to improve the effect of early diagnosis and treatment. Long non-coding RNA (lncRNA) THAP7-AS1 is known to be highly expressed in gastric cancer, but has been less studied in other cancers. The aim of the study is to explore the role and mechanism of methyltransferase-like 3 (METTL3) mediated up-regulation of N6-methyladenosine (m6A) modified lncRNA THAP7-AS1 expression in promoting the development of lung cancer.@*METHODS@#Samples of 120 lung cancer and corresponding paracancerous tissues were collected. LncRNA microarrays were used to analyze differentially expressed lncRNAs. THAP7-AS1 levels were detected in lung cancer, adjacent normal tissues and lung cancer cell lines by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The diagnostic value of THAP7-AS1 in lung cancer and the relationship between THAP7-AS1 expression and survival rate and clinicopathological parameters were analyzed. Bioinformatics analysis, methylated RNA immunoprecipitation (meRIP), RNA pull-down and RNA-immunoprecipitation (RIP) assay were used to investigate the molecular regulation mechanism of THAP7-AS1. Cell proliferation, migration, invasion and tumorigenesis of SPC-A-1 and NCI-H1299 cells were determined by MTS, colony-formation, scratch, Transwell and xenotransplantation in vivo, respectively. Expression levels of phosphoinositide 3-kinase/protein kenase B (PI3K/AKT) signal pathway related protein were detected by Western blot.@*RESULTS@#Expression levels of THAP7-AS1 were higher in lung cancer tissues and cell lines (P<0.05). THAP7-AS1 has certain diagnostic value in lung cancer [area under the curve (AUC)=0.737], and its expression associated with overall survival rate, tumor size, tumor-node-metastasis (TNM) stage and lymph node metastasis (P<0.05). METTL3-mediated m6A modification enhanced THAP7-AS1 expression. The cell proliferation, migration, invasion and the volume and mass of transplanted tumor were all higher in the THAP7-AS1 group compared with the NC group and sh-NC group of SPC-A-1 and NCI-H1299 cells, while the cell proliferation, migration and invasion were lower in the sh-THAP7-AS1 group (P<0.05). THAP7-AS1 binds specifically to Cullin 4B (CUL4B). The cell proliferation, migration, invasion, and expression levels of phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA), phosphoinositide-3 kinase, catalytic subunit delta (PIK3CD), phospho-phosphatidylinositol 3-kinase (p-PI3K), phospho-protein kinase B (p-AKT) and phospho-mammalian target of rapamycin (p-mTOR) were higher in the THAP7-AS1 group compared with the Vector group of SPC-A-1 and NCI-H1299 cells (P<0.05).@*CONCLUSIONS@#LncRNA THAP7-AS1 is stably expressed through m6A modification mediated by METTL3, and combines with CUL4B to activate PI3K/AKT signal pathway, which promotes the occurrence and development of lung cancer.

Promotion effect of FOXCUT as a microRNA sponge for miR-24-3p on progression in triple-negative breast cancer through the p38 MAPK signaling pathway / 中华医学杂志(英文版)

BACKGROUND@#Triple-negative breast cancer (TNBC) is a type of highly invasive breast cancer with a poor prognosis. According to new research, long noncoding RNAs (lncRNAs) play a significant role in the progression of cancer. Although the role of lncRNAs in breast cancer has been well reported, few studies have focused on TNBC. This study aimed to explore the biological function and clinical significance of forkhead box C1 promoter upstream transcript (FOXCUT) in triple-negative breast cancer.@*METHODS@#Based on a bioinformatic analysis of the cancer genome atlas (TCGA) database, we detected that the lncRNA FOXCUT was overexpressed in TNBC tissues, which was further validated in an external cohort of tissues from the General Surgery Department of the First Affiliated Hospital of Nanjing Medical University. The functions of FOXCUT in proliferation, migration, and invasion were detected in vitro or in vivo. Luciferase assays and RNA immunoprecipitation (RIP) were performed to reveal that FOXCUT acted as a competitive endogenous RNA (ceRNA) for the microRNA miR-24-3p and consequently inhibited the degradation of p38.@*RESULTS@#lncRNA FOXCUT was markedly highly expressed in breast cancer, which was associated with poor prognosis in some cases. Knockdown of FOXCUT significantly inhibited cancer growth and metastasis in vitro or in vivo. Mechanistically, FOXCUT competitively bounded to miR-24-3p to prevent the degradation of p38, which might act as an oncogene in breast cancer.@*CONCLUSION@#Collectively, this research revealed a novel FOXCUT/miR-24-3p/p38 axis that affected breast cancer progression and suggested that the lncRNA FOXCUT could be a diagnostic marker and therapeutic target for breast cancer.

Effect of LncRNA GATA3-AS1 Targeting MiR-515-5p on Cell Proliferation and Apoptosis in Childhood Acute Lymphoblastic Leukemia Cells / 中国实验血液学杂志

OBJECTIVE@#To investigate the effects of long non-coding RNA (lncRNA) GATA3 antisense RNA 1 (GATA3-AS1) targeting miR-515-5p on the proliferation and apoptosis of childhood acute lymphoblastic leukemia (ALL) cells.@*METHODS@#RT-qPCR was used to determine the expression of GATA3-AS1 and miR-515-5p in the plasma of controls and ALL children. Human ALL cells Jurkat were divided into si-GATA3-AS1, si-NC, miR-NC, miR-515-5p, si-GATA3-AS1+anti-miR-NC and si-GATA3-AS1+anti-miR-515-5p groups. CCK-8 assay was used to detect the cell proliferation, and flow cytometry was used to detect the cell apoptosis. The targeting relationship between GATA3-AS1 and miR-515-5p was determined by dual-luciferase reporter assay.@*RESULTS@#The expression level of GATA3-AS1 in the plasma of ALL children was significantly higher than that of controls (P <0.001), while the expression level of miR-515-5p was significantly lower than that of controls (P <0.001). Compared with the si-NC group, the cell inhibition rate, apoptosis rate, and miR-515-5p expression level in si-GATA3-AS1 group were significantly increased (P <0.001). Compared with the miR-NC group, the cell inhibition rate and apoptosis rate in miR-515-5p group were significantly increased (P <0.001). GATA3-AS1 could directly and specifically bind to miR-515-5p. Compared with the si-GATA3-AS1+anti-miR-NC group, the cell inhibition rate and apoptosis rate in si-GATA3-AS1+anti-miR-515-5p group were significantly decreased (P <0.001).@*CONCLUSION@#Down-regulation of GATA3-AS1 can inhibit proliferation and induce apoptosis of childhood ALL cells by targeting up-regulation of miR-515-5p expression.

Long non-coding RNA colon cancer-associated transcript 1-Vimentin axis promoting the migration and invasion of HeLa cells / 中华医学杂志(英文版)

BACKGROUND@#Long non-coding RNA colon cancer-associated transcript 1 (CCAT1) is involved in transforming multiple cancers into malignant cancer types. Previous studies underlining the mechanisms of the functions of CCAT1 primarily focused on its decoy for miRNAs (micro RNAs). However, the regulatory mechanism of CCAT1-protein interaction associated with tumor metastasis is still largely unknown. The present study aimed to identify proteome-wide CCAT1 partners and explored the CCAT1-protein interaction mediated tumor metastasis.@*METHODS@#CCAT1-proteins complexes were purified and identified using RNA antisense purification coupled with the mass spectrometry (RAP-MS) method. The database for annotation, visualization, and integrated discovery and database for eukaryotic RNA binding proteins (EuRBPDB) websites were used to bioinformatic analyzing CCAT1 binding proteins. RNA pull-down and RNA immunoprecipitation were used to validate CCAT1-Vimentin interaction. Transwell assay was used to evaluate the migration and invasion abilities of HeLa cells.@*RESULTS@#RAP-MS method worked well by culturing cells with nucleoside analog 4-thiouridine, and cross-linking was performed using 365 nm wavelength ultraviolet. There were 631 proteins identified, out of which about 60% were RNA binding proteins recorded by the EuRBPDB database. Vimentin was one of the CCAT1 binding proteins and participated in the tumor metastasis pathway. Knocked down vimetin ( VIM ) and rescued the downregulation by overexpressing CCAT1 demonstrated that CCAT1 could enhance tumor migration and invasion abilities by stabilizing Vimentin protein.@*CONCLUSION@#CCAT1 may bind with and stabilize Vimentin protein, thus enhancing cancer cell migration and invasion abilities.

Matrix stiffening related lncRNA SNHG8 regulates chemosensitivity of ovarian cancer / 生物医学工程学杂志

Extracellular matrix (ECM) has been implicated in tumor progress and chemosensitivity. Ovarian cancer brings a great threat to the health of women with a significant feature of high mortality and poor prognosis. However, the potential significance of matrix stiffness in the pattern of long non-coding RNAs (lncRNAs) expression and ovarian cancer drug sensitivity is still largely unkown. Here, based on RNA-seq data of ovarian cancer cell cultured on substrates with different stiffness, we found that a great amount of lncRNAs were upregulated in stiff group, whereas SNHG8 was significantly downregulated, which was further verified in ovarian cancer cells cultured on polydimethylsiloxane (PDMS) hydrogel. Knockdown of SNHG8 led to an impaired efficiency of homologous repair, and decreased cellular sensitivity to both etoposide and cisplatin. Meanwhile, the results of the GEPIA analysis indicated that the expression of SNHG8 was significantly decreased in ovarian cancer tissues, which was negatively correlated with the overall survival of patients with ovarian cancer. In conclusion, matrix stiffening related lncRNA SNHG8 is closely related to chemosensitivity and prognosis of ovarian cancer, which might be a novel molecular marker for chemotherapy drug instruction and prognosis prediction.

The effect of lncRNA ADPGK-AS1 on the proliferation and apoptosis of retinoblastoma cells by targeting miR-200b-5p / 中华肿瘤杂志

Objective: To explore the effect of lncRNA ADPGK-AS1 on the proliferation and apoptosis of retinoblastoma cells and its possible mechanism. Methods: The tumor tissues of 31 patients with retinoblastoma admitted to Henan Provincial Eye Hospital from February to June 2020 and their corresponding normal tissues adjacent to the cancer were collected. The expression levels of lncRNA ADPGK-AS1 and miR-200b-5p in retinoblastoma tissues and normal adjacent tissues were detected by real-time fluorescence quantitative polymerase chain reaction (qRT-PCR). Human retinal epithelial cell ARPE-19, human retinoblastoma cell Y-79 and WERI-Rb-1 were cultured in vitro. The expression levels of lncRNA ADPGK-AS1 and miR-200b-5p were detected by qRT-PCR. Y-79 cells were randomly divided into si-con group, si-lncRNA ADPGK-AS1 group, miR con group, miR-200b-5p group, si-lncRNA ADPGK-AS1+ anti-miR con group, and si-lncRNA ADPGK-AS1+ anti-miR-200b-5p group. The proliferation, cloning and apoptosis of cells in each group were detected by tetramethylazol blue method, plate cloning test and flow cytometry, respectively. The targeting relationship between lncRNA ADPGK-AS1 and miR-200b-5p was detected by double luciferase report test, and the expression level of cleaved-caspase-3 protein was detected by western blot. Results: Compared with the adjacent tissues, the expression of lncRNA ADPGK-AS1 in retinoblastoma tissues was increased (P<0.05), while the expression of miR-200b-5p was decreased (P<0.05). Compared with ARPE-19 cells, the expression of lncRNA ADPGK-AS1 in Y-79 and WERI-Rb-1 cells was increased (P<0.05), while the expression of miR-200b-5p was decreased (P<0.05). Compared with the si-con group, the cell viability of the si-lncRNA ADPGK-AS1 group was reduced (1.06±0.09 vs 0.53±0.05, P<0.05), the number of cell clone formation was reduced (114.00±8.03 vs 57.00±4.13, P<0.05), while the apoptosis rate [(7.93±0.68)% vs (25.43±1.94)%] and the protein level of cleaved-caspase-3 were increased (P<0.05). Compared with the miR-con group, the cell viability of the miR-200b-5p group was decreased (1.05±0.08 vs 0.57±0.05, P<0.05), the number of cell clone formation was decreased (118.00±10.02 vs 64.00±5.13, P<0.05), while the apoptosis rate [(7.89±0.71)% vs (23.15±1.62)%] and the protein level of cleaved-caspase-3 were increased (P<0.05). lncRNA ADPGK-AS1 could target the expression of miR-200b-5p. Compared with the si-lncRNA ADPGK-AS1+ anti-miR-con group, cell viability of the si-lncRNA ADPGK-AS1+ anti-miR-200b-5p group was increased (0.53±0.04 vs 1.25±0.10, P<0.05), and the number of cell clones was increased (54.00±4.39 vs 125.00±10.03, P<0.05), while the rate of apoptosis [(25.38±1.53)% vs (9.76±0.71)%] and the protein level of cleaved-caspase-3 were decreased (P<0.05). Conclusion: Interfering with the expression of lncRNA ADPGK-AS1 could inhibit the proliferation and clone formation and induce apoptosis of retinoblastoma cells by targeting the expression of miR-200b-5p.

lncR-GAS5 upregulates the splicing factor SRSF10 to impair endothelial autophagy, leading to atherogenesis / 医学前沿

Long noncoding RNAs (lncRNAs) play a critical role in the regulation of atherosclerosis. Here, we investigated the role of the lncRNA growth arrest-specific 5 (lncR-GAS5) in atherogenesis. We found that the enforced expression of lncR-GAS5 contributed to the development of atherosclerosis, which presented as increased plaque size and reduced collagen content. Moreover, impaired autophagy was observed, as shown by a decreased LC3II/LC3I protein ratio and an elevated P62 level in lncR-GAS5-overexpressing human aortic endothelial cells. By contrast, lncR-GAS5 knockdown promoted autophagy. Moreover, serine/arginine-rich splicing factor 10 (SRSF10) knockdown increased the LC3II/LC3I ratio and decreased the P62 level, thus enhancing the formation of autophagic vacuoles, autolysosomes, and autophagosomes. Mechanistically, lncR-GAS5 regulated the downstream splicing factor SRSF10 to impair autophagy in the endothelium, which was reversed by the knockdown of SRSF10. Further results revealed that overexpression of the lncR-GAS5-targeted gene miR-193-5p promoted autophagy and autophagic vacuole accumulation by repressing its direct target gene, SRSF10. Notably, miR-193-5p overexpression decreased plaque size and increased collagen content. Altogether, these findings demonstrate that lncR-GAS5 partially contributes to atherogenesis and plaque instability by impairing endothelial autophagy. In conclusion, lncR-GAS5 overexpression arrested endothelial autophagy through the miR-193-5p/SRSF10 signaling pathway. Thus, miR-193-5p/SRSF10 may serve as a novel treatment target for atherosclerosis.

The expression of long non-coding RNA human leukocyte antigen complex P5(lncRNA HCP5) in synovial tissue of patients with rheumatoid arthritis is up-regulated and correlated with immune cell infiltration / 细胞与分子免疫学杂志

Objective To identify the potential long non-coding RNA (lncRNA) expressed in rheumatoid arthritis (RA) synovium key to RA onset and investigate its association with immune cell infiltration. Methods RA synovium data were downloaded from the GEO database and normalized. The lncRNAs key to RA onset were identified using multiple machine learning methods. Infiltration of 22 immune cell populations in RA synovium was measured by cell-type identification by estimating relative subsets of RNA transcripts (CIBER-SORT). The relationship between the key lncRNA and infiltrating immune cells was analyzed. Finally, real-time quantitative PCR was applied to validate the expression of the key lncRNA in RA synovial cells. Results lncRNA human leukocyte antigen complex P5(HCP5) was identified as the key lncRNA associated with RA onset. Infiltration analysis revealed increased abundance of CD8+ T cells, γδ T cells, and M1 macrophages while decreased abundance of M2 macrophages in RA synovial tissue. Correlation analysis demonstrated that the lncRNA HCP5 expression was positively associated with the infiltration abundance of CD8+ T cells, γδ T cells, and M1 macrophages in RA synovial tissue. Furthermore,the expression of lncRNA HCP5 in RA synovial cells was up-regulated. Conclusion lncRNA HCP5 expression is up-regulated in RA synovial tissue and potentially associated with immune cells infiltration.

Knock-down of long intergenic noncoding RNA cyclooxygenase 2 (lincRNA-COX2) inhibits apoptosis and polarization into M1 in Listeria monocytogenes-infected macrophages / 细胞与分子免疫学杂志

Objective To investigate the effect of long intergenic non-coding RNA COX2 (lincRNA-COX2) on apoptosis and polarization of Listeria monocytogenes (Lm)-infected RAW264.7 cells. Methods RAW264.7 cells were cultured and divided into control group (uninfected cells), Lm infection group, negative control of small interfering RNA (si-NC) group, si-NC and Lm infection group, small interfering RNA of lincRNA-COX2 (si-lincRNA-COX2) group, si-lincRNA-COX2 and Lm infection group. RAW264.7 cells were infected with MOI=10 Lm for 6 hours, and then the inhibition efficiency of siRNA transfection was detected by fluorescence microscope and quantitative real-time PCR (qRT-PCR). The expression levels of cleaved-caspase-3(c-caspase-3), caspase-3, B-cell lymphoma-2 (Bcl2), Bcl2 associated X protein (BAX), arginase 1 (Arg1), inducible nitric oxide synthase (iNOS) were detected by Western blot analysis. Results c-caspase-3/caspase-3, BAX/Bcl2 and iNOS were significantly up-regulated, while the level of Arg1 was down-regulated in Lm-infected RAW264.7 cells compared with control group. LincRNA-COX2 knockdown inhibited the increase of protein levels for BAX/Bcl2, c-caspase-3/caspase-3 and iNOS in Lm-infected RAW264.7 cells, while the level of Arg1 in Lm-infected RAW264.7 cells was up-regulated. Conclusion Knockdown of lincRNA-COX2 can inhibit cell apoptosis and suppress the macrophage polarization into M1 type in Lm-infected RAW264.7 cells.

Prognostic value and mechanism of long non-coding RNA DLEU1 in osteosarcoma / 中国骨伤

OBJECTIVE@#To investigate the prognostic value and mechanism of long non-coding RNA DLEU1(LncRNA DLEU1) in osteosarcoma.@*METHODS@#The tissue samples and clinical data of 86 patients with osteosarcoma treated by orthopaedic surgery in our hospital from January 2012 to December 2014 were retrospectively collected. The expression of LncRNA DLEU1 in pathological tissues was detected by qRT-PCR, then the patients were divided into high and low expression of LncRNA DLEU1 groups. Osteosarcoma cell line HOS was divided into two groups, down-regulated expression group (si-DLEU1 group) and negative control group (si-NC group). LncRNA DLEU1 siRNA and negative control sequence were transfected by Lipofectamine 3000. Chi-square test was used to analyze the relationship between the expression of LncRNA DLEU1 and the clinicopathological factors of osteosarcoma. Kaplan-Meier method was used to compare the difference of the overall survival rate of osteosarcoma patients between the high and low expression groups of LncRNA DLEU1. The risk factors affecting the overall survival rate of osteosarcoma were analyzed by single factor and multifactor analysis. The number of invasive cells in the two groups was determined and compared by Transwell assay.@*RESULTS@#The expression of LncRNA DLEU1 in osteosarcoma tissue was higher than that in adjacent tissues (P<0.001). The expression of LncRNA DLEU1 in human osteosarcoma cell lines (MG-63, U-2 OS, and HOS) was significantly higher than that in human osteoblast line hFOB 1.19 (P<0.001). The expression of LncRNA DLEU1 was significantly correlated with Enneking stage (P<0.001), distant metastasis (P=0.016), and histological grade (P=0.028). The 1-year overall survival rate of the LncRNA DLEU1 high expression group was significantly higher than that of the low expression group (90.7% vs 60.5%, P<0.001). The 5-year overall survival rate of the LncRNA DLEU1 high expression group was significantly higher than that of the low expression group (32.6% vs 11.6%, P<0.001). Univariate analysis showed that Enneking stage (P<0.001), tumor size (P=0.043), distant metastasis (P<0.001), histological grade (P<0.001), and expression of LncRNA DLEU1 (P<0.001) were risk factors for overall survival of osteosarcoma patients. Multivariate analysis showed that high expression of LncRNA DLEU1 [HR=1.948, 95% CI(1.141, 3.641), P=0.012] and distant metastasis[HR=4.108, 95% CI(2.169, 7.780), P<0.001] were independent risk factors for overall survival of osteosarcoma patients. The number of invasive cells in si-DLEU1 group was significantly lesser than that in si-NC group(139±13 vs 357±31, P<0.001).@*CONCLUSION@#High expression of LncRNA DLEU1 is a molecular marker affecting the prognosis of osteosarcoma patients. Downregulation of LncRNA DLEU1 can inhibit the invasion of osteosarcoma cells.

H19 recruited N 6 -methyladenosine (m 6 A) reader YTHDF1 to promote SCARB1 translation and facilitate angiogenesis in gastric cancer / 中华医学杂志(英文版)

BACKGROUND@#Angiogenesis is described as a complex process in which new microvessels sprout from endothelial cells of existing vasculature. This study aimed to determine whether long non-coding RNA (lncRNA) H19 induced the angiogenesis of gastric cancer (GC) and its possible mechanism.@*METHODS@#Gene expression level was determined by quantitative real-time polymerase chain reaction and western blotting. Cell counting kit-8, transwell, 5-Ethynyl-2'-deoxyuridine (EdU), colony formation assay, and human umbilical vein endothelial cells (HUVECs) angiogenesis assay as well as Matrigel plug assay were conducted to study the proliferation, migration, and angiogenesis of GC in vitro and in vivo . The binding protein of H19 was found by RNA pull-down and RNA Immunoprecipitation (RIP). High-throughput sequencing was performed and next Gene Ontology (GO) as well as Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis was conducted to analyze the genes that are under H19 regulation. Methylated RIP (me-RIP) assay was used to investigate the sites and abundance among target mRNA. The transcription factor acted as upstream of H19 was determined through chromatin immunoprecipitation (ChIP) and luciferase assay.@*RESULTS@#In this study, we found that hypoxia-induced factor (HIF)-1α could bind to the promoter region of H19, leading to H19 overexpression. High expression of H19 was correlated with angiogenesis in GC, and H19 knocking down could inhibit cell proliferation, migration and angiogenesis. Mechanistically, the oncogenic role of H19 was achieved by binding with the N 6 -methyladenosine (m 6 A) reader YTH domain-containing family protein 1 (YTHDF1), which could recognize the m 6 A site on the 3'-untransated regions (3'-UTR) of scavenger receptor class B member 1 (SCARB1) mRNA, resulting in over-translation of SCARB1 and thus promoting the proliferation, migration, and angiogenesis of GC cells.@*CONCLUSION@#HIF-1α induced overexpression of H19 via binding with the promoter of H19, and H19 promoted GC cells proliferation, migration and angiogenesis through YTHDF1/SCARB1, which might be a beneficial target for antiangiogenic therapy for GC.

lncRNA AC005224.4/miR-140-3p/SNAI2 regulating axis facilitates the invasion and metastasis of ovarian cancer through epithelial-mesenchymal transition / 中华医学杂志(英文版)

BACKGROUND@#Ovarian cancer is one of the most widespread malignant diseases of the female reproductive system worldwide. The plurality of ovarian cancer is diagnosed with metastasis in the abdominal cavity. Epithelial-mesenchymal transition (EMT) exerts a vital role in tumor cell metastasis. However, it remains unclear whether long non-coding RNA (lncRNA) are implicated in EMT and influence ovarian cancer cell invasion and metastasis. This study was designed to investigate the impacts of lncRNA AC005224.4 on ovarian cancer.@*METHODS@#LncRNA AC005224.4, miR-140-3p, and snail family transcriptional repressor 2 ( SNAI2 ) expression levels in ovarian cancer and normal ovarian tissues were determined using real-time quantitative polymerase chain reaction (qRT-PCR). Cell Counting Kit-8 (CCK-8) and Transwell (migration and invasion) assays were conducted to measure SKOV3 and CAOV-3 cell proliferation and metastasis. E-cadherin, N-cadherin, Snail, and Vimentin contents were detected using Western blot. Nude mouse xenograft assay was utilized to validate AC005224.4 effects in vivo . Dual-luciferase reporter gene assay confirmed the targeted relationship between miR-140-3p and AC005224.4 or SNAI2 .@*RESULTS@#AC005224.4 and SNAI2 upregulation and miR-140-3p downregulation were observed in ovarian cancer tissues and cells. Silencing of AC005224.4 observably moderated SKOV3 and CAOV-3 cell proliferation, migration, invasion, and EMT process in vitro and impaired the tumorigenesis in vivo . miR-140-3p was a target of AC005224.4 and its reduced expression level was mediated by AC005224.4. miR-140-3p mimics decreased the proliferation, migration, and invasion of ovarian cancer cells. SNAI2 was identified as a novel target of miR-140-3p and its expression level was promoted by either AC005224.4 overexpression or miR-140-3p knockdown. Overexpression of SNAI2 also facilitated ovarian cancer cell viability and metastasis.@*CONCLUSION@#AC005224.4 was confirmed as an oncogene via sponging miR-140-3p and promoted SNAI2 expression, contributing to better understanding of ovarian cancer pathogenesis and shedding light on exploiting the novel lncRNA-directed therapy against ovarian cancer.

Research Progress of Long Non-Coding RNA in Hematological Tumors --Review / 中国实验血液学杂志

Long non-coding RNA (lncRNA) is a hot topic in the field of researching tumor pathogenesis, and the importance in hematologic malignancies has been gradually being elucidated. LncRNA not only regulates hematological tumorigenesis and progression through affecting various biological processes such as cell proliferation, differentiation, pluripotency and apoptosis; moreover, abnormal expression and mutation of lncRNA are closely related to drug resistance and prognosis. Thus lncRNA can be used as novel biomarker and potential therapeutic target for hematological tumors. In this review, we will focus on the latest progress of lncRNA in hematological tumors to provide new ideas for the clinical diagnosis, prognostic evaluation together with research and development of target drugs for hematologic malignancies.

Research Progress of Long Non-coding RNA in Acute Myeloid Leukemia--Review / 中国实验血液学杂志

Long non-coding RNA (lncRNA) is not "transcriptional noise". It can regulate gene expression at pre-transcriptional, post-transcriptional and epigenetic level and participate in the occurrence and development of diseases. A large number of studies have shown that the abnormal expression of lncRNA plays an important role in the occurrence and development of acute myeloid leukemia (AML) and drug resistance. LncRNA can participate in the occurrence, development and drug resistance of AML by acting on target genes and regulating related signal pathways. Detection of its expression has a certain prognostic value. Therefore, this article briefly discusses the research progress of lncRNA in AML, hoping to provide ideas for clinical diagnosis and targeted therapy.

Lnc-TMEM132D-AS1 overexpression reduces sensitivity of non-small cell lung cancer cells to osimertinib / 南方医科大学学报

OBJECTIVE@#To screen the differentially expressed long non-coding RNAs (lncRNAs) in non-small cell lung cancer (NSCLC) cells with acquired resistance to osimertinib and explore their roles in drug resistance of the cells.@*METHODS@#The cell lines H1975_OR and HCC827_OR with acquired osimertinib resistance were derived from their osimertinib-sensitive parental NSCLC cell lines H1975 and HCC827, respectively, and their sensitivity to osimertinib was assessed with CCK-8 assay, clone formation assay and flow cytometry. RNA sequencing (RNA-seq) and real-time quantitative PCR (qPCR) were used to screen the differentially expressed lncRNAs in osimertinib-resistant cells. The role of the identified lncRNA in osimertinib resistance was explored using CCK-8, clone formation and Transwell assays, and its subcellular localization and downstream targets were analyzed by nucleoplasmic separation, bioinformatics analysis and qPCR.@*RESULTS@#The resistance index of H1975_OR and HCC827_OR cells to osimertinib was 598.70 and 428.82, respectively (P < 0.001), and the two cell lines showed significantly increased proliferation and colony-forming abilities with decreased apoptosis (P < 0.01). RNA-seq identified 34 differentially expressed lncRNAs in osimertinib-resistant cells, and among them lnc-TMEM132D-AS1 showed the highest increase of expression after acquired osimertinib resistance (P < 0.01). Analysis of the TCGA database suggested that the level of lnc-TMEM132D-AS1 was significantly higher in NSCLC than in adjacent tissues (P < 0.001), and its high expression was associated with a poor prognosis of the patients. In osimertinib-sensitive cells, overexpression of Lnc-TMEM132D-AS1 obviously promoted cell proliferation, colony formation and migration (P < 0.05), while Lnc-TMEM132D-AS1 knockdown partially restored osimertinib sensitivity of the resistant cells (P < 0.01). Lnc-TMEM132D-AS1 was localized mainly in the cytoplasm, and bioinformatics analysis suggested that hsa-miR-766-5p was its candidate target, and their expression levels were inversely correlated. The target mRNAs of hsa-miR-766-5p were mainly enriched in the Ras signaling pathway.@*CONCLUSION@#The expression of lnc-TMEM132D-AS1 is significantly upregulated in NSCLC cells with acquired osimertinib resistance, and may serve as a potential biomarker and therapeutic target for osimertinibresistant NSCLC.

Effect of long non-coding RNA 114227 on gastric cancer cell proliferation and migration / 中南大学学报(医学版)

OBJECTIVES@#Gastric cancer is a common cancer of the digestive system. Long non-coding RNA (lncRNA) plays an important role in the formation and development of gastric cancer. This study aims to investigate the effect of long non-coding lncRNA 114227 on biologic behaviors in gastric cancer cells.@*METHODS@#The experiment was divided into 4 groups: a negative control (NC) group, a lncRNA 114227 small interference (si-lncRNA 114227) group, an empty vector (Vector) group, and an overexpression vector (OE-lncRNA 114227) group. The expressions of lncRNA 114227 in gastric mucosa and gastric cancer tissues, gastric mucosal epithelial cells and different gastric cancer strains were determined by real-time reverse transcription PCR (real-time RT-PCR).The proliferation were detected by CCK-8 assay in gastric cancer cells. The epithelial-mesenchymal transformation (EMT) was utilized by Transwell assay, scratch healing assay, and Western blotting in gastric cancer cells. The effect of lncRNA 114227 on proliferation of gastric cancer cells was detected by tumor bearing experiment in nude mice in vivo.@*RESULTS@#The expression level of lncRNA 114227 in the gastric cancer tissues was significantly lower than that in the gastric mucosa tissues, and in 4 kinds of gastric cancer strains was all significantly lower than that in gastric mucosal epithelial cells (all P<0.01). In vitro, the proliferation and migration abilities of gastric cells were significantly reduced after overexpressing lncRNA 114227, and cell proliferation and migration were enhanced after silencing lncRNA 114227 (all P<0.05). The results of in vivo subcutaneous tumorigenesis in nude mice showed that the tumorigenic volume of the tumor-bearing mice in the OE-lncRNA 114227 group was significantly smaller than that of the Vector group, and the tumorigenic quality was lower than that of the Vector group (P<0.05), indicating that lncRNA 114227 inhibited tumorigenesis.@*CONCLUSIONS@#The expression of lncRNA 114227 is downregulated in gastric cancer gastric cancer tissues and cell lines. LncRNA 114227 may inhibit the proliferation and migration of gastric cancer cells through EMT process.

Long noncoding RNA LOC646029 functions as a ceRNA to suppress ovarian cancer progression through the miR-627-3p/SPRED1 axis / 医学前沿

Long noncoding RNAs (lncRNAs) play a crucial regulatory role in the development and progression of multiple cancers. However, the potential mechanism by which lncRNAs affect the recurrence and metastasis of ovarian cancer remains unclear. In the current study, the lncRNA LOC646029 was markedly downregulated in metastatic ovarian tumors compared with primary tumors. Gain- and loss-of-function assays demonstrated that LOC646029 inhibits the proliferation, invasiveness, and metastasis of ovarian cancer cells in vivo and in vitro. Moreover, the downregulation of LOC646029 in metastatic ovarian tumors was strongly correlated with poor prognosis. Mechanistically, LOC646029 served as a miR-627-3p sponge to promote the expression of Sprouty-related EVH1 domain-containing protein 1, which is necessary for suppressing tumor metastasis and inhibiting KRAS signaling. Collectively, our results demonstrated that LOC646029 is involved in the progression and metastasis of ovarian cancer, which may be a potential prognostic biomarker.

Cell cycle related long non-coding RNAs as the critical regulators of breast cancer progression and metastasis

Cell cycle is one of the main cellular mechanisms involved in tumor progression. Almost all of the active molecular pathways in tumor cells directly or indirectly target the cell cycle progression. Therefore, it is necessary to assess the molecular mechanisms involved in cell cycle regulation in tumor cells. Since, early diagnosis has pivotal role in better cancer management and treatment, it is required to introduce the non-invasive diagnostic markers. Long non-coding RNAs (LncRNAs) have higher stability in body fluids in comparison with mRNAs. Therefore, they can be used as efficient non-invasive markers for the early detection of breast cancer (BCa). In the present review we have summarized all of the reported lncRNAs involved in cell cycle regulation in BCa. It has been reported that lncRNAs mainly affect the cell cycle in G1/S transition through the CCND1/CDK4-6 complex. Present review paves the way of introducing the cell cycle related lncRNAs as efficient markers for the early detection of BCa.

Diagnostic and prognostic significance of long noncoding RNA LINC00173 in patients with melanoma

SUMMARY OBJECTIVE: A growing volume of literature has suggested long noncoding RNAs (lncRNAs) as important players in tumor progression. In this study, we aimed to investigate the expression and prognostic value of lncRNA LINC00173 (LINC00173) in melanoma. METHODS: LINC00173 expression was measured in 163 paired cancerous and noncancerous specimen samples by real-time polymerase chain reaction. The correlations between LINC00173 expression with clinicopathological characteristics and prognosis were analyzed by chi-square test, log-rank test, and multivariate survival analysis. Receiver-operating characteristic curves were used for the assessment of the diagnostic value of LINC00173 for melanoma patients. RESULTS: The expression level of LINC00173 in melanoma specimens was distinctly higher than that in adjacent non-neoplasm specimens (p<0.01). Besides, LINC00173 was expressed more frequently in patients with advanced melanoma than in patients with early melanoma. Multivariate assays confirmed that LINC00173 expression level was an independent prognostic predictor of melanoma patients (p<0.05). CONCLUSION: Our data indicated that LINC00173 expression could serve as an unfavorable prognostic biomarker for melanoma patients.

LncRNA-m18as1 competitively binds with miR-18a-5p to regulate follicle-stimulating hormone secretion through the Smad2/3 pathway in rat primary pituitary cells / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Long noncoding RNAs (lncRNAs) are expressed in different species and different tissues, and perform different functions, but little is known about their involvement in the synthesis or secretion of follicle-stimulating hormone (FSH). In general, we have revealed lncRNA‍‒‍microRNA (miRNA)‍‒‍‍messenger RNA (mRNA) interactions that may play important roles in rat primary pituitary cells. In this study, a new lncRNA was identified for the first time. First, we analyzed the gene expression of lncRNA-m18as1 in different tissues and different stages by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and observed the localization of lncRNA-m18as1 with fluorescence in situ hybridization, which indicated that this lncRNA was distributed mainly in the cytoplasm. Next, we used RT-qPCR and enzyme-linked immunosorbent assay (ELISA) to analyze the regulation of FSH synthesis and secretion after overexpression or knockdown of lncRNA-m18as1 and found that lncRNA-m18as1 was positively correlated with FSH synthesis and secretion. In addition, mothers against decapentaplegic homolog 2 (Smad2) was highly expressed in our sequencing results. We also screened miR-18a-5p from our sequencing results as a miRNA that may bind to lncRNA-m18as1 and Smad2. We used RNA immunoprecipitation-qPCR (RIP-qPCR) and/or dual luciferase assays to confirm that lncRNA-m18as1 interacted with miR-18a-5p and miR-18a-5p interacted with Smad2. Fluorescence in situ hybridization (FISH) showed that lncRNA-m18as1 and miR-18a-5p were localized mainly in the cytoplasm. Finally, we determined the relationship among lncRNA-m18as1, miR-18a-5p, and the Smad2/3 pathway. Overall, we found that lncRNA-m18as1 acts as a molecular sponge of miR-18a-5p to regulate the synthesis and secretion of FSH through the Smad2/3 pathway.