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BackgroundLong noncoding RNAs (lncRNAs) are closely related to the occurrence and development of cancer. Gastric adenocarcinoma-associated, positive CD44 regulator, long intergenic noncoding RNA (GAPLINC) is a recently identified lncRNA that can actively participate in the tumorigenesis of various cancers. Here, we investigated the functional roles and mechanism of GAPLINC in renal cell carcinoma (RCC) development.MethodsDifferentially expressed lncRNAs between RCC tissues and normal kidney tissues were detected by using a microarray technique. RNA sequencing was applied to explore the mRNA expression profile changes after GAPLINC silencing. After gain- and loss-of-function approaches were implemented, the effect of GAPLINC on RCC in vitro and in vivo was assessed by cell proliferation and migration assays. Moreover, rescue experiments and luciferase reporter assays were used to study the interactions between GAPLINC, miR-135b-5p and CSF1.ResultsGAPLINC was significantly upregulated in RCC tissues and cell lines and was associated with a poor prognosis in RCC patients. Knockdown of GAPLINC repressed RCC growth in vitro and in vivo, while overexpression of GAPLINC exhibited the opposite effect. Mechanistically, we found that GAPLINC upregulates oncogene CSF1 expression by acting as a sponge of miR-135b-5p.ConclusionTaken together, our results suggest that GAPLINC is a novel prognostic marker and molecular therapeutic target for RCC.

Significance Inflammation has largely been studied in the context of protein-coding genes. Recent studies have uncovered lncRNAs as important regulators of immunity. The functional characterization of these genes remains an active area of research. In this study, we identify GAPLINC as a functionally conserved lncRNA between human and mouse. GAPLINC depletion results in enhanced expression of immune response genes that are direct NF-κB targets. Astoundingly, we observe that Gaplinc knockout mice show resistance to LPS-induced endotoxic shock and find that basal expression of inflammatory genes prevents clot formation to protect against multiorgan failure and death. These findings have implications in the treatment of sepsis, in which new therapies targeting lncRNAs can contribute valuable information in understanding inflammation and improving patient outcome., Recent studies have identified thousands of long noncoding RNAs (lncRNAs) in mammalian genomes that regulate gene expression in different biological processes. Although lncRNAs have been identified in a variety of immune cells and implicated in immune response, the biological function and mechanism of the majority remain unexplored, especially in sepsis. Here, we identify a role for a lncRNA—gastric adenocarcinoma predictive long intergenic noncoding RNA (GAPLINC)—previously characterized for its role in cancer, now in the context of innate immunity, macrophages, and LPS-induced endotoxic shock. Transcriptome analysis of macrophages from humans and mice reveals that GAPLINC is a conserved lncRNA that is highly expressed following macrophage differentiation. Upon inflammatory activation, GAPLINC is rapidly down-regulated. Macrophages depleted of GAPLINC display enhanced expression of inflammatory genes at baseline, while overexpression of GAPLINC suppresses this response. Consistent with GAPLINC-depleted cells, Gaplinc knockout mice display enhanced basal levels of inflammatory genes and show resistance to LPS-induced endotoxic shock. Mechanistically, survival is linked to increased levels of nuclear NF-κB in Gaplinc knockout mice that drives basal expression of target genes typically only activated following inflammatory stimulation. We show that this activation of immune response genes prior to LPS challenge leads to decreased blood clot formation, which protects Gaplinc knockout mice from multiorgan failure and death. Together, our results identify a previously unknown function for GAPLINC as a negative regulator of inflammation and uncover a key role for this lncRNA in modulating endotoxic shock.

Peng Wang,1,&ast; Song Yang,1,&ast; Shengbin Dai,1 Qingtao Ni,1 Huilan Liu,1 Lei Yu,1 Kaijin Lu,2 Gaohua Han,1 Junxing Huang1 1Department of Oncology, The Fifth Affiliated Hospital of Nantong University (Jiangsu Taizhou People’s Hospital), Taizhou, Jiangsu, 225300, People’s Republic of China; 2Department of Thoracic Surgery, The Fifth Affiliated Hospital of Nantong University, Jiangsu Taizhou People’s Hospital, Taizhou, Jiangsu, 225300, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Gaohua Han; Junxing HuangDepartment of Oncology, Jiangsu Taizhou People’s Hospital, The Fifth Affiliated Hospital of Nantong University (Jiangsu Taizhou People’s Hospital), 399 Hailing South Road, Taizhou, 225300, Jiangsu, People’s Republic of ChinaTel +8613852613099; +8613515153996Email danny_75@126.com; huangjunxing_a@163.comBackground: The long noncoding RNA (lncRNA) GAPLINC, or gastric adenocarcinoma predictive long intergenic ncRNA, plays a carcinogenic role in a variety of different tumor types. There is limited information regarding the biological function of GAPLINC in the development of esophageal squamous cell carcinoma (ESCC).Methods: Surgical tissue samples of 40 patients undergoing ESCC radical surgery were collected, including ESCC tissues and corresponding adjacent normal tissues. Quantitative real-time PCR (qRT-PCR) was used to detect the expression of lncRNA GAPLINC in the human ESCC cell line (TE11). The function role of LncRNA GAPLINC was detected after specific siRNA interference and overexpression in the TE11 cell line. The effects of LncRNA GAPLINC on ESCC cell proliferation, migration and invasion abilities were investigated by flow cytometry, using the Cell Counting Kit-8 (CCK-8), and by Transwell migration assays, respectively.Results: The expression of lncRNA GAPLINC in ESCC tissues was significantly higher than that in corresponding adjacent normal tissues (P< 0.05) and correlated with the degree of tumor differentiation (P< 0.05). Compared with human esophageal normal epithelial cell lines, the expression of LncRNA GAPLINC was significantly higher in the human ESCC cell line (P< 0.05). CCK-8 assays showed that LncRNA GAPLINC overexpression increased the growth rate of cells (P< 0.05). Transwell experiments showed that LncRNA GAPLINC overexpression increased the ability of cell migration and invasion compared to control cells (P< 0.05). Annexin V assay revealed that LncRNA GAPLINC silencing increased early stage apoptosis (P< 0. 05).Conclusion: Our results suggest that LncRNA GAPLINC may be used as a biomarker for the diagnosis and monitoring of ESCC, and may play an oncogenic role in ESCC.Keywords: esophageal squamous cell carcinoma, long non-coding RNA, GAPLINC, biomarker, expression

In this study, we investigated the role of a long non‐coding RNA GAPLINC in angiogenesis using human umbilical vein endothelial cells (HUVEC). We found that hypoxia and hypoxia‐inducible factor 1α (HIF‐1α) increased the expression of GAPLINC in HUVEC cells. Moreover, GAPLINC overexpression down‐regulated miR‐211 and up‐regulated Bcl2 protein expression. Further rescue experiments confirmed that hypoxia directly increased GAPLINC expression. GAPLINC overexpression also increased cell migration and vessel formation which promoted angiogenesis, and these changes were attributed to the increased expression of vascular endothelial growth factor receptors (VEGFR) and delta‐like canonical notch ligand 4 (DLL4) receptors. Finally, we demonstrated that GAPLINC promotes vessel formation and migration by regulating MAPK and NF‐kB signalling pathways. Taken together, these findings comprehensively demonstrate that overexpression of GAPLINC increases HUVEC cells angiogenesis under hypoxia condition suggesting that GAPLINC can be a potential target for critical limb ischaemia (CLI) treatment.

// Peng Yang 1, * , Tao Chen 1, * , Zipeng Xu 1 , Hua Zhu 2 , Jie Wang 2 , Zhenyu He 1, 2 1 The Second Clinical Medical College of Nanjing Medical University, Nanjing, China 2 Department of General Surgery, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, China * These authors have contributed equally to this work Correspondence to: Zhenyu He, email: hezhenyu1968@126.com Keywords: colorectal cancer, GAPLINC, long noncoding RNA, NONO, PSF Received: March 18, 2016 Accepted: May 13, 2016 Published: May 31, 2016 ABSTRACT This study aimed to investigate the role of long noncoding RNAs (lncRNAs) in the metastasis of colorectal cancer (CRC). Metastasis is an important prognostic factor of CRC, and lncRNAs have been implicated in tumor proliferation and metastasis. The human CRC cell lines HCT116, HT29, SW480, DLD-1, and SW620 were used in the study. Genome-wide lncRNA expression patterns in metastatic lymph nodes compared with paired normal lymph nodes of CRC were assessed by microarray analysis. Gastric adenocarcinoma predictive long intergenic noncoding (GAPLINC) RNA was detected via functional prediction. The increased expression of GAPLINC was found to be positively correlated with larger tumor size, advanced tumor stage (T stage), advanced node stage (N stage), increased death, and shorter survival of patients with CRC by in situ hybridization analysis. Besides, the decreased expression of GAPLINC could significantly repress CRC cell invasion in vitro and also inhibit proliferation in vitro and in vivo . RNA pull-down with mass spectrum experiments revealed that PTB-associated splicing factor (PSF) and non-POU-domain-containing octamer-binding (NONO) protein bound to GAPLINC and reversed the effect of GAPLINC on cell invasion. Gene array and bioinformatics analyses identified that snail family zinc finger 2 (SNAI2) was involved in the biological processes of GAPLINC/PSF/NONO. This study indicated the importance of GAPLINC in promoting CRC invasion via binding to PSF/NONO and partly by stimulating the expression of SNAI2. Hence, GAPLINC may serve as a promising target for CRC diagnosis and therapy. The findings may help in developing a novel therapeutic strategy for patients with CRC.

Lingyun Diao,1,2 Shengying Wang,2 Zhiguang Sun1 1Department of Gastroenterology, The First Clinical Medical School of Nanjing University of Chinese Medicine, Nanjing, People’s Republic of China; 2Department of Gastroenterology, Xuzhou City Hospital of Traditional Chinese Medicine, Xuzhou, People’s Republic of China Background: Dysregulated long noncoding RNAs (lncRNAs) and microRNAs (miRNAs) play key roles in the development of human cancers. LncRNA GAPLINC has been reported to be increased in gastric cancer (GC) tissues.Methods: Real-time PCR assays were used to measure expressions of GAPLINC, miR-378, and MAPK1 mRNA. Western blot assays were employed to examine MAPK1 protein expression. Cell proliferation and cell cycle were measured by CCK-8 and propidium iodide-detection assays, respectively. The interaction between GAPLINC and miR-378 was confirmed by site-directed mutagenesis and luciferase assays. Luciferase assays were also used to study whether GAPLINC was able to act as a molecular sponge of miR-378 to modulate MAPK1 expression.Results: The lncRNA GAPLINC expression was upregulated and positively correlated with MAPK1 expression in gastric cancer tissues and cells. Additionally, lncRNA GAPLINC promoted the expression of MAPK1 and the enhancement of GC cell proliferation and cell cycle progression by LncRNA GAPLINC was dependent on MAPK1 in vitro and in vivo. Consequently, we found that miR-378 expression was inversely correlated with GAPLINC expression in GC tissues and cells. miR-378 could directly bind to GAPLINC and decreased GAPLINC expression, thus reducing MAPK1 expression. Furthermore, overexpression of miR-378 inhibited MAPK1 expression, cell proliferation, and cell cycle progression of gastric cancer cells, while these effects were abrogated by upregulating lncRNA GAPLINC expression.Conclusion: Taken together, lncRNA GAPLINC promotes gastric cancer cell proliferation by acting as a molecular sponge of miR-378 to modulate MAPK1 expression.Keywords: GAPLINC, cell proliferation, miR-378, MAPK1, gastric cancer&nbsp

Hypoxia-inducible factor (HIF) activates the transcription of genes involved in cancer progression. Recently, HIF was reported to regulate the transcription of non-coding RNAs. Here, we show that the transcription of a long non-coding RNA (lncRNA), Gastric Adenocarcinoma Associated, Positive CD44 Regulator, Long Intergenic Non-Coding RNA (GAPLINC), is directly activated by HIF-1α in gastric cancer (GC). GAPLINC was overexpressed in GC tissues and promoted tumor migration and invasive behavior. GAPLINC overexpression was associated with poor prognosis in GC patients. Luciferase reporter assays and chromatin immunoprecipitation assays confirmed that HIF-1α binds to the promoter region of GAPLINC and activates its transcription. GAPLINC knockdown inhibited hypoxia-induced tumor proliferation in vivo. Taken together, our results identified a novel role for HIF transcriptional pathways in GC tumorigenesis mediated by the regulation of the lncRNA GAPLINC, and suggest GAPLINC as a novel therapeutic target for reversing chemoradioresistance and prolonging survival.