Lnc HAGLR Promotes Colon Cancer Progression Through Sponging miR-185-5p and Activating CDK4 and CDK6 in vitro and in vivo

CD44 knockdown alters miRNA expression and their target genes in colon cancer

Introduction

Metastasis formation poses a significant challenge to oncologists, as it severely limits the survival of colorectal cancer (CRC) patients. Recently, we demonstrated that CD44 promotes spontaneous distant metastasis in a CRC xenograft model. The depletion of CD44 was associated with reduction in hypoxia, EMT, as well as improved mitochondrial metabolism in primary tumor. Collectively, these effects decreased the metastatic potential of the CRC xenograft tumors under investigation. In this study we explore the molecular mechanisms by which CD44 knockdown (kd) leads to such substantial changes of tumor properties.

Methods

Using miRNA-Seq data combined with bioinformatic analysis, we investigated the role of miRNA expression changes in the metastasis prevention observed with CD44 kd.

Results

Among the differentially expressed miRNAs, three members of Let-7 family (let-7a-5p, let-7b-5p, and let-7c-5p), two isoforms of miR-203a (canonical miR-203a-3p and its +1 5'-isoform), miR-101-3p, miR-200b-3p|+1 5'-isoform, miR-125a-5p, and miR-185-5p were identified as potentially involved in regulating CD44-mediated metastasis. Gene set analysis of differentially expressed mRNA targets of these miRNAs, along with an examination of key regulators driving the observed changes in both mRNA and miRNA expression profiles, suggests that the CD44-STAT3-Let-7 miRNA axis as one of the most relevant in regulation of colon cancer metastasis via the CD44 receptor.

Discussion

Our findings suggest a regulatory relationship between CD44, Let-7 miRNAs, and STAT3 in HT-29 tumors. Additionally, we propose the potential involvement of both isoforms of miR-203a (canonical and its +1 5'-isoform) in this regulatory network and suggest a role for miR-101-3p and miR-125a-5p in metastasis regulation through CD44 kd.

Comprehensive analysis of ferroptosis-related long non-coding RNA and its association with tumor progression and ferroptosis in gastric cancer

Gastric cancer (GC) is one of the most common malignant tumors with a poor prognosis. Ferroptosis is an distinct type of non-apoptotic cell death that is closely associated with tumor prognosis. Thus, we aimed to develop an novel prognosis risk model based on ferroptosis-related lncRNAs and excavate novel diagnostic markers. In this study, eight ferroptosis-related lncRNAs were obtained for constructing the prognosis model in GC based on TCGA database. The patients in the high-risk group had worse survival than those in the low-risk group, and the risk-grouping could be used as an independent prognostic factor for OS. Receiver operating characteristic curve analysis demonstrated this risk model was superior to traditional clinicopathological features in predicting GC prognosis. GSEA revealed that these lncRNAs were mainly involved in cell adhesion, cancer pathways, and immune function regulation. The key gene HAGLR of this risk signature was up-regulated in GC tissues and cells. Function assays showed that knockdown of HAGLR could effectively inhibit the GC cells proliferation and migration, whereas silencing HAGLR accelerated apoptosis and ferroptosis cell death process. In conclusion, we established a novel ferroptosis-related prognostic risk signature including eight lncRNAs, which may improve prognostic predictive accuracy for patients with GC.

Inhibition of hERG by ESEE suppresses the progression of colorectal cancer

Colorectal cancer (CRC) is one of the most common malignant cancers. Emodin is a lipophilic anthraquinone commonly found in medicinal herbs and known for its antitumor properties. However, its clinical utility has been hampered by low druggability. We designed and synthesized a new compound named Emodin succinimidyl ethyl ester (ESEE), which improves the bioavailability and preserves the original pharmacological effects of Emodin. In vitro, we have confirmed that ESEE induces apoptosis in colon cancer cells, suppresses cell proliferation, migration, and invasion, and inhibits the growth of subcutaneous transplantation tumors associated with colon cancer. And, in vivo, ESEE robustly inhibited tumor growth. Human Ether-a-go-go Related Gene (hERG) is aberrantly expressed in various cancer cells, where they play an important role in cancer progression. Focal adhesion kinase (FAK) is a tyrosine kinase overexpressed in cancer cells and plays an important role in the progression of tumors to a malignant phenotype. Mechanistically, the anti-CRC properties of ESEE are exerted through direct binding with hERG, which impedes the FAK/PI3K/AKT signaling axis-dependent apoptotic cascade.

Knockdown of LncRNA-HAGLR restrains the viability and motility of pancreatic cancer via miR-625-5p/TAF15 axis in vitro and in vivo

Dysregulation of long non-coding RNAs (lncRNAs) has been strongly involved to the development of pancreatic cancer (PC). However, the potential mechanisms by which lncRNA regulate PC development still need to be further explored. We attempted to elucidate the functional role and regulatory mechanism of lncRNA HAGLR on PC progression in vitro and vivo. RT-qPCR, Western blot, RNA pull-down, luciferase reporter assay, RNA immunoprecipitation assay, CCK-8 assay, EdU assay, flow cytometry, transwell assay and xenograft tumor experiment were performed in this study. We found that the expressions of HAGLR and TAF15 were increased in PC tissues and cells. HAGLR silencing restrained the PC cell growth and invasion, but induced cell apoptosis. Moreover, HAGLR targeted miR-625-5p to modulate the expression of TAF15. HAGLR overexpression partially eliminated the suppressive effect of TAF15 depletion on PC cell growth and the stimulative effect on apoptosis. In vivo assays showed that HAGLR knockdown inhibited PC cell growth by regulating the TAF15 expression. These findings suggest HAGLR could facilitate PC cell malignant behaviors through regulating the TAF15 expression, demonstrating that HAGLR might be a valuable target for the PC treatment.

LncRNA FOXD2-AS1 promotes the growth, invasion and migration of OSCC cells by regulating the MiR-185-5p/PLOD1/Akt/mTOR pathway

Although lncRNAs are recognized to contribute to the development of oral squamous-cell carcinoma (OSCC), their exact function in invasion and cell migration is not clear. In this research, we explored the molecular and cellular mechanisms of FOXD2-AS1 in OSCC. Prognostic and bioinformatics analyses were used to test for the differential expression of FOXD2-AS1-PLOD1. Following FOXD2-AS1 suppression or overexpression, changes in cell viability were measured using the CCK-8 test; changes in cell migration and invasion abilities were measured using the migration and the Transwell assay. The expression of associated genes and proteins was found using Western blot and RT-qPCR. Analysis of luciferase reporter genes was done to look for regulatory connections between various molecules. The FOXD2-AS1-PLOD1 pair, which was highly expressed in OSCC, was analyzed and experimentally verified to be closely related to the prognosis of OSCC, and a nomogram model and correction curve were constructed. The inhibition of FOXD2-AS1 resulted in the reduction of cell activity, migration, invasion ability and changes in genes related to invasion and migration. In vivo validation showed that inhibition of FOXD2-AS1 expression slowed tumor growth, and related proteins changed accordingly. The experiments verified that FOXD2-AS1 negatively regulated miR-185-5 p and that miR-185-5 p negatively regulated PLOD1. In addition, it was found that the expression of PLOD1, p-Akt and p-mTOR proteins in OSCC cells was reduced by the inhibition of FOXD2-AS1, and FOXD2-AS1 and PLOD1 were closely related to the Akt/mTOR pathway. Increased expression of FOXD2-AS1 promotes OSCC growth, invasion and migration, which is important in part by targeting miR-185-5 p/PLOD1/Akt/mTOR pathway activity.

HAGLR, stabilized by m6A modification, triggers PTEN-Akt signaling cascade-mediated RPE cell pyroptosis via sponging miR-106b-5p

Consistent hyperglycaemia on retinal microvascular tissues is recognized as a vital inducer of diabetic retinopathy (DR) pathogenesis. In view of the essential functionality of long noncoding RNAs (lncRNAs) in multiple human diseases, we aim to figure out the exact role and underlying mechanisms of lncRNA HOXD Cluster Antisense RNA 1 (HAGLR) in DR pathogenesis. Serum specimens from patients with proliferative DR and healthy volunteers were collected for measuring HAGLR levels. Human primary retinal pigment epithelium (HRPE) cells kept in high glucose (HG) condition were applied to simulating hyperglycaemia of DR pathology in vitro. Cell proliferation, apoptosis, either pyroptosis was assess using Cell Counting Kit-8 TUNEL, flow cytometry, and enzyme-linked immunoassay assays. Bioinformatics analysis was subjected to examine the interaction between HAGLR and N6-methyladenosine (m6A)-bind protein IGF2BP2, as determined using RNA immunoprecipitation and RNA pull-down. Luciferase reporter assay was performed to assess the HAGLR-miR-106b-5p-PTEN axis. Levels of pyroptosis-associated biomarkers were detected using western blotting. Aberrantly overexpressed HAGLR was uncovered in the serum samples of DR patients and HG-induced HRPE cells, of which knockdown attenuated HG-induced cytotoxic impacts on cell apoptosis and pyroptosis. Whereas, reinforced HAGLR further aggravated these effects. IGF2BP2 positively regulated HAGLR in a m6A-dependent manner. HAGLR served as a sponge for miR-106b-5p to upregulate PTEN, thereby activating Akt signaling cascade. Rescue assays demonstrated that PTEN overexpression abolished the inhibition of silenced HAGLR on pyroptosis in HRPE cells. HAGLR, epigenetically modified by IGF2BP2 in an m6A-dependent manner, functioned as a sponge for miR-106b-5p, thereby activating PTEN/Akt signaling cascade to accelerate DR pathology.

LncRNA HAGLR May Aggravate Melanoma Malignancy Via miR-4644/ASB11 Pathway

In this study, we aimed to assess the biological functions of HAGLR and its underlying mechanisms in melanoma. HAGLR and ASB11 were knocked down by transfection with the corresponding siRNAs. Meanwhile, miR-4644 was downregulated using the miR-4644 inhibitor treatment. The target interactions among the three molecules were demonstrated using dual-luciferase reporter and RNA immunoprecipitation assays. The levels of HAGLR, miR-4644, and ASB11 in melanoma cells and tissues were assessed using quantitative real‑time PCR and western blotting. The functions and mechanisms underlying HAGLR action in melanoma progression were examined using Cell Counting Kit-8, Transwell, Caspase-3 activity, and xenograft tumor formation assays. HAGLR and ASB11 expression were elevated, whereas that of miR-4644 was downregulated in melanoma cells and tissues. The viability and migration of melanoma cells (A875 and A375) were markedly suppressed by the knockdown of HAGLR and ASB11 but promoted following miR-4644 inhibitor transfection. In contrast, apoptosis showed the opposite trend. In vivo, tumor weight declined considerably with downregulation of HAGLR. Mechanistically, HAGLR sponges miR-4644, increasing the levels of ASB11 and further aggravating melanoma. It latter negatively targets ASB11 in melanoma cells. Hence, the HAGLR-miR-4644-ASB11 axis may be a promising target for melanoma treatment.

Long non-coding RNA Homeobox D gene cluster antisense growth-associated long noncoding RNA/microRNA-182-5p/Homeobox protein A10 alleviates postmenopausal osteoporosis via accelerating osteoblast differentiation of bone marrow mesenchymal stem cells

BACKGROUND

Studies have illuminated that long non-coding RNA (lncRNA) influences bone cell differentiation and formation. Nevertheless, whether lncRNA Homeobox D gene cluster antisense growth-associated long noncoding RNA (HAGLR) was implicated in postmenopausal osteoporosis (PMOP) was yet uncertain.

PURPOSE

The research was to explore HAGLR's role in the osteogenic differentiation (OD) process of bone marrow mesenchymal stem cells (BMSCs).

METHODS

BMSCs were isolated from mouse bone marrow tissues and identified by electron microscope and flow cytometry. HAGLR, microRNA (miR)-182-5p, and homeobox protein A10 (Hoxa10) levels in BMSCs were detected. Mouse BMSC OD process was induced, and calcium deposition and alkaline phosphatase content were analyzed, as well as expressions of runt-related transcription factor 2, osteopontin, and osteocalcin, and cell apoptosis. Bilateral ovaries were resected from mice to construct the ovariectomized model and bone mineral density, maximum bending stress, maximum load, and elastic modulus of the femur were tested, and the femur was histopathologically evaluated. Chondrocyte apoptosis in the articular cartilage of mice was analyzed. Analysis of the interaction of HAGLR, miR-182-5p with Hoxa10 was conducted.

RESULTS

HAGLR and Hoxa10 were down-regulated and miR-182-5p was elevated in PMOP patients. During the BMSC OD process, HAGLR and Hoxa10 levels were suppressed, while miR-182-5p was elevated. Promotion of HAGLR or suppression of miR-182-5p accelerated OD of BMSCs. Inhibition of miR-182-5p reversed the inhibitory effect of HAGLR on BMSC OD. In in vivo experiments, up-regulating HAGLR alleviated PMOP, while silencing Hoxa10 reversed the effects of upregulating HAGLR. HAGLR performed as a sponge for miR-182-5p, while miR-182-5p targeted Hoxa10.

CONCLUSION

In general, HAGLR boosted the OD process of BMSCs and relieved PMOP via the miR-182-5p/Hoxa10 axis. These data preliminarily reveal the key role of HAGLR in PMOP, and the research results have a certain reference for the treatment of PMOP.

Noncoding RNA-Mediated High Expression of PFKFB3 Correlates with Poor Prognosis and Tumor Immune Infiltration of Lung Adenocarcinoma

Background

There is growing evidence showing that 6-phosphofructo-2-kinase (PFKFB3) plays crucial roles in different types of human cancers, including LUAD; however, the specific mechanism by which PFKFB3 plays a role in LUAD remains unclear.

Methods

We investigated the expression of PFKFB3 and explored the underlying mechanism as well as the correlation with immune markers using several online datasets, such as Tumor Immune Estimate Resource (TIMER), UALCAN, and the Cancer Genome Atlas (TCGA) databases, miRWalk, Targetscan, MiRDB and starBase database. Western blot and immunohistochemistry analysis were performed to verify the corresponding outcomes.

Results

It was shown that the mRNA expression of PFKFB3 was lower in LUAD than in the normal tissues, while its protein expression was not consistent with the mRNA level. The expression of PFKFB3 was correlated with clinicopathological parameters and several signaling pathways. The potential long chain (lnc)RNA/microRNA/PFKFB3 axis and the possible mechanism by which tumor progression in LUAD is promoted was predicted. We obtained the LINC01798/LINC02086/AP000845.1/HAGLR-miR-17-5p-PFKFB3 axis after comprehensive analyses of expression, correlation, and survival. Moreover, the expression of PFKFB3 was positively correlated with immune cells and immune checkpoint expression, including PD-1, PD-L1 and CTLA-4.

Conclusion

The present study demonstrated that noncoding RNAs mediated the upregulation of PFKFB3 and was associated with a poor prognosis and immune tumor infiltration in LUAD.

Cell Cycle-Related lncRNAs as Innovative Targets to Advance Cancer Management

Long non-coding RNAs (lncRNAs) are non-coding RNAs (ncRNAs) longer than 200nt. They have complex biological functions and take part in multiple fundamental biological processes, such as cell proliferation, differentiation, survival and apoptosis. Recent studies suggest that lncRNAs modulate critical regulatory proteins involved in cancer cell cycle, such as cyclin, cell cycle protein-dependent kinases (CDK) and cell cycle protein-dependent kinase inhibitors (CKI) through different mechanisms. To clarify the role of lncRNAs in the regulation of cell cycle will provide new ideas for design of antitumor therapies which intervene with the cell cycle progression. In this paper, we review the recent studies about the controlling of lncRNAs on cell cycle related proteins such as cyclin, CDK and CKI in different cancers. We further outline the different mechanisms involved in this regulation and describe the emerging role of cell cycle-related lncRNAs in cancer diagnosis and therapy.

Immune cell death-related lncRNA signature as a predictive factor of clinical outcomes and immune checkpoints in gastric cancer

Background: Immune cell death (ICD) is a type of tumor cell death that has recently been shown to activate and regulate tumor immunity. However, the role of ICD-related long non-coding RNAs (lncRNAs) in gastric cancer remains to be clarified. Methods: We obtained 375 tumor samples from the Cancer Genome Atlas (TCGA) database and randomly assigned them to training and verification groups. LASSO and Cox regression analysis were utilized to identify ICD-related lncRNAs and establish a risk model. The changes in the immune microenvironment of the two groups were compared by examining the tumor-infiltrating immune cells. Results: We established a tumor signature based on nine ICD-related lncRNAs. In light of the receiver operating characteristic and Kaplan-Meier curves, the prognostic values of this risk model were verified. Multivariate regression analysis showed that the risk score was an independent risk factor for the prognosis of patients in both the training cohort (HR 2.52; 95% CI: 1.65-3.87) and validation cohort (HR 2.70; 95% CI: 1.54-4.8). A nomogram was developed to predict the 1-, 3-, and 5-year survival of patients with gastric cancer, and the signature was linked to high levels of immunological checkpoint expression (B7-H3, VSIR). Conclusions: An ICD-related lncRNA signature could predict the immune response and prognosis of patients with gastric cancer. This prognostic signature could be employed to independently monitor the efficacy of immunotherapy for gastric cancer patients.

Lycorine weakens tamoxifen resistance of breast cancer via abrogating HAGLR-mediated epigenetic suppression on VGLL4 by DNMT1

Much is known about the significance of lycorine, a natural alkaloid, in combating various types of cancer, including breast cancer (BC), but whether it participates in regulating tamoxifen (TAM) resistance and its underlying mechanism remain to be elucidated. Tamoxifen-resistant (TAMR) BC cells were first established by continuously exposed to increasing concentrations of TAM. Levels of targeted gene including HOXD antisense growth-associated lncRNA (HAGLR) and Vestigial like family member 4 (VGLL4) were analyzed by qRT-PCR and western blot, respectively. Cell proliferation ability was assessed by MTT and EdU assays. Flow cytometry was carried out to evaluate the apoptosis. VGLL4 promoter methylation was examined using methylation specific PCR (MSP). The role of HAGLR acting on the expression of VGLL4 via DNA hypermethylation was confirmed by RNA immunoprecipitation (RIP). Here, we reported that lycorine administration reduced the survival ratio of TAMR BC cells, decreased the IC₅₀ of TAM, and strengthened TAM-induced apoptosis. HAGLR, observed to be highly expressed in TAMR BC cells, was identified to be a downstream effector of lycorine, of which overexpression abolished lycorine-mediated TAMR inhibition. VGLL4 served as a target of HAGLR in regulating lycorine-mediated suppression on tamoxifen resistance of TAMR BC cells. Mechanistically, HAGLR epigenetically suppressed VGLL4 expression via DNA methyltransferase 1 (DNMT1)-mediated DNA hypermethylation. Taken together, our data highlights the pivotal role of lycorine in TAM resistance of BC, which may provide a potential agent for improving the effectiveness and efficacy of BC resistance.

RUNX3 Meets the Ubiquitin-Proteasome System in Cancer

RUNX3 is a transcription factor with regulatory roles in cell proliferation and development. While largely characterized as a tumor suppressor, RUNX3 can also be oncogenic in certain cancers. Many factors account for the tumor suppressor function of RUNX3, which is reflected by its ability to suppress cancer cell proliferation after expression-restoration, and its inactivation in cancer cells. Ubiquitination and proteasomal degradation represent a major mechanism for the inactivation of RUNX3 and the suppression of cancer cell proliferation. On the one hand, RUNX3 has been shown to facilitate the ubiquitination and proteasomal degradation of oncogenic proteins. On the other hand, RUNX3 can be inactivated through the ubiquitin-proteasome system. This review encapsulates two facets of RUNX3 in cancer: how RUNX3 suppresses cell proliferation by facilitating the ubiquitination and proteasomal degradation of oncogenic proteins, and how RUNX3 is degraded itself through interacting RNA-, protein-, and pathogen-mediated ubiquitination and proteasomal degradation.

lncRNA HCG11 Promotes Colorectal Cancer Cell Malignant Behaviors via Sponging miR-26b-5p

Colorectal cancer (CRC) is a type of gastrointestinal cancer with an increasing incidence. Long noncoding RNAs (lncRNAs) have raised great concern because of wide participation in human diseases, including cancers. However, whether lncRNA HLA complex group 11 (HCG11) played a functional role in CRC remained to be elucidated. Herein, we utilized qRT-PCR to analyze the expression of HCG11 and found that HCG11 was highly expressed in CRC cells. Besides, HCG11 knockdown suppressed cell proliferation, migration, and invasion but facilitated cell apoptosis. Furthermore, supported by bioinformatics analyses and mechanism assays, HCG11, mainly located in cell cytoplasm, was confirmed to competitively bind to miR-26b-5p to modulate the expression of the target messenger RNA (mRNA), namely, cAMP-regulated phosphoprotein 19 (ARPP19). ARPP19 was detected to be upregulated in CRC cells, and ARPP19 silence was verified to inhibit the malignant behaviors of CRC cells. Rescue experiments validated that miR-26b-5p inhibition or ARPP19 overexpression could countervail the inhibitory influences of HCG11 silence on CRC cell biological behaviors in vitro. To conclude, HCG11, upregulated in CRC cells, could promote cell proliferation, migration, and invasion and inhibit cell apoptosis via targeting miR-26b-5p/ARPP19 axis.

An epithelial-mesenchymal transition-related mRNA signature associated with the prognosis, immune infiltration and therapeutic response of colon adenocarcinoma

Background: Epithelial-mesenchymal transition (EMT) is closely associated with cancer cell metastasis. Colon adenocarcinoma (COAD) is one of the most common malignancies in the world, and its metastasis leading to poor prognosis remains a challenge for clinicians. The purpose of this study was to explore the prognostic value of EMT-related genes (EMTRGs) by bioinformatics analysis and to develop a new EMTRGs prognostic signature for COAD. Methods: The TCGA-COAD dataset was downloaded from the TCGA portal as the training cohort, and the GSE17538 and GSE29621 datasets were obtained from the GEO database as the validation cohort. The best EMTRGs prognostic signature was constructed by differential expression analysis, Cox, and LASSO regression analysis. Gene set enrichment analysis (GSEA) is used to reveal pathways that are enriched in high-risk and low-risk groups. Differences in tumor immune cell levels were analyzed using microenvironmental cell population counter and single sample gene set enrichment analysis. Subclass mapping analysis and Genomics of Drug Sensitivity in Cancer were applied for prediction of immunotherapy response and chemotherapy response, respectively. Results: A total of 77 differentially expressed EMTRGs were identified in the TCGA-COAD cohort, and they were significantly associated with functions and pathways related to cancer cell metastasis, proliferation, and apoptosis. We constructed EMTRGs prognostic signature with COMP, MYL9, PCOLCE2, SCG2, and TIMP1 as new COAD prognostic biomarkers. The high-risk group had a poorer prognosis with enhanced immune cell infiltration. The GSEA demonstrated that the high-risk group was involved in "ECM Receptor Interaction," "WNT Signaling Pathway" and "Colorectal Cancer." Furthermore, patients with high risk scores may respond to anti-CTLA4 therapy and may be more resistant to targeted therapy agents BI 2536 and ABT-888. Conclusion: Together, we developed a new EMTRGs prognostic signature that can be an independent prognostic factor for COAD. This study has guiding implications for individualized counseling and treatment of COAD patients.

A review on the role of cyclin dependent kinases in cancers

The Cyclin-dependent kinase (CDK) class of serine/threonine kinases has crucial roles in the regulation of cell cycle transition and is mainly involved in the pathogenesis of cancers. The expression of CDKs is controlled by a complex regulatory network comprised of genetic and epigenetic mechanisms, which are dysregulated during the progression of cancer. The abnormal activation of CDKs results in uncontrolled cancer cell proliferation and the induction of cancer stem cell characteristics. The levels of CDKs can be utilized to predict the prognosis and treatment response of cancer patients, and further understanding of the function and underlying mechanisms of CDKs in human tumors would pave the way for future cancer therapies that effectively target CDKs. Defects in the regulation of cell cycle and mutations in the genes coding cell-cycle regulatory proteins lead to unrestrained proliferation of cells leading to formation of tumors. A number of treatment modalities have been designed to combat dysregulation of cell cycle through affecting expression or activity of CDKs. However, effective application of these methods in the clinical settings requires recognition of the role of CDKs in the progression of each type of cancer, their partners, their interactions with signaling pathways and the effects of suppression of these kinases on malignant features. Thus, we designed this literature search to summarize these findings at cellular level, as well as in vivo and clinical levels.

The emerging potentials of lncRNA DRAIC in human cancers

Long non-coding RNA (lncRNA) is a subtype of noncoding RNA that has more than 200 nucleotides. Numerous studies have confirmed that lncRNA is relevant during multiple biological processes through the regulation of various genes, thus affecting disease progression. The lncRNA DRAIC, a newly discovered lncRNA, has been found to be abnormally expressed in a variety of diseases, particularly cancer. Indeed, the dysregulation of DRAIC expression is closely related to clinicopathological features. It was also reported that DRAIC is key to biological functions such as cell proliferation, autophagy, migration, and invasion. Furthermore, DRAIC is of great clinical significance in human disease. In this review, we discuss the expression signature, clinical characteristics, biological functions, relevant mechanisms, and potential clinical applications of DRAIC in several human diseases.

Circ_0114428 promotes proliferation, fibrosis and EMT process of high glucose-induced glomerular mesangial cells through regulating the miR-185-5p/SMAD3 axis

Circular RNA (circRNA) has been confirmed to be the key regulators of diabetic nephropathy (DN) progression. However, the role of circ_0114428 in the DN progression remains unclear. Glomerular mesangial cells (GMCs) were treated with high glucose (HG) to mimic DN cell models in vitro. The expression levels of circ_0114428, microRNA (miR)-185-5p, and SMAD3 mRNA were examined by quantitative real-time PCR. Cell proliferation ability was detected by MTT assay, EdU staining and flow cytometry. The protein levels of proliferation marker, fibrosis markers, epithelial-mesenchymal transition (EMT) markers and SMAD3 were measured by western blot assay. The interaction between miR-185-5p and circ_0114428 or SMAD3 was confirmed via dual-luciferase reporter assay, RIP assay and RNA pull-down assay. Our data showed that circ_0114428 was upregulated in HG-induced GMCs. Circ_0114428 overexpression could aggravate the promotion effect of HG on the proliferation, fibrosis and EMT process of GMCs, while its knockdown had an opposite effect. In the terms of mechanisms, circ_0114428 could sponge miR-185-5p to regulate SMAD3. MiR-185-5p inhibitor could reverse the suppressive effect of circ_0114428 knockdown on the proliferation, fibrosis and EMT process in HG-induced GMCs. Also, SMAD3 overexpression abolished the inhibition of miR-185-5p on the proliferation, fibrosis and EMT process in HG-induced GMCs. Taken together, our data suggested that circ_0114428 might promote DN progression by regulating the miR-185-5p/SMAD3 axis.

Overexpressed lncRNA LINC00893 Suppresses Progression of Colon Cancer by Binding with miR-146b-3p to Upregulate PRSS8

Background

Long noncoding RNAs (lncRNAs) play a significant role in the progression and metastasis of various cancers. LINC00893 has been reported to exert antitumor effect on various cancers such as gastric cancer and thyroid cancer. Bioinformatics analysis also predicted that LINC00893 was downregulated in colon cancer. However, the clinical significance and regulating mechanism of LINC00893 in colon cancer remain unknown.

Methods

Expression of LINC00893, miR-146b-3p, and PRSS8 was detected in colon cancer tissues and adjacent nontumor tissues by RT-qPCR, and clinical significance was analyzed by receiver operating characteristic curve. The regulatory mechanism of LINC00893, miR-146b-3p, and PRSS8 was investigated by dual luciferase reporter and RNA pull-down assays. Proliferation, migration, invasion, and apoptosis were measured in HCT116 and SW620 cells by MTT, EdU staining, wound healing, Transwell, TUNEL, and flow-cytometry assays. Moreover, the effect of LINC00893 on colon cancer progression was further evaluated in tumor-bearing mice.

Results

LINC00893 and PRSS8 were significantly downregulated, while miR-146b-3p was upregulated in colon cancer tissues compared to control group. LINC00893, miR-146b-3p, and PRSS8 had significant diagnostic value with area under curve of 0.9383, 0.7300, and 0.9644, respectively. Overexpressed LINC00893 or silenced miR-146b-3p suppressed the proliferation, migration, and invasion while promoting apoptosis in colon cancer cells (HCT116, SW620). Moreover, miR-146b-3p overexpression reversed the inhibitory effect of LINC00893, while PRSS8 knockdown rescued the suppressive effect of miR-146b-3p inhibitor on malignant cell behaviors in colon cancer. Furthermore, the tumor growth in mice was significantly reduced by LINC00893 overexpression.

Conclusion

LINC00893 overexpression suppressed the progression of colon cancer by binding with miR-146b-3p to upregulate PRSS8. LINC00893 and its downstream molecules miR-146b-3p and PRSS8 may serve as novel biomarkers and therapeutic targets of colon cancer, providing new treatment options and research approaches towards colon cancer.

A chemoresistance lncRNA signature for recurrence risk stratification of colon cancer patients with chemotherapy

Chemotherapy is considered the nonsurgical treatment of choice for colon cancer patients. However, no precise molecular markers are available to determine which patients can actually benefit from it. In this study, we identified 55 chemotherapy-specific long non-coding RNAs (lncRNAs) of colon cancer patients through a systematic assessment of lncRNA expression profiles from a public database. These were taken from multiple cohorts of colon cancer patients who had received chemotherapy, or not. Based on these data, a chemoresistance lncRNA signature, named CRLSig, was constructed and successfully applied to divide chemotherapy patients into two groups with different recurrence-free survival (RFS) rates. Gene set enrichment analysis revealed that patients with low CRLSig had more infiltrating CD8+ T cells and macrophages, while those with high CRLSig had more infiltrating natural killer T cells. KEGG pathway analysis revealed that the low CRLSig group had more activated metabolic pathways compared with those in the high CRLSig group, indicating better response to chemotherapy. Single-cell sequencing analysis revealed that stromal cells and epithelial cells had higher CRLSig. Thus, we have constructed an auxiliary prognostic tool, CRLSig, able to discriminate patients at high risk of RFS, despite having received standard adjuvant chemotherapy treatment.

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A CRLSig was constructed for the first time

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CRLSig revealed chemotherapy patients with different RFS rates

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Low CRLSig group had more activated metabolic pathways

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ScRNA-seq analysis revealed stromal cells and epithelial cells had higher CRLSig

MiR-185-5p suppresses acute myeloid leukemia by inhibiting GPX1

Acute myeloid leukemia (AML) has been characterized by the swift development of abnormal cells in the bone marrow. This research aimed to examine the impacts of the miR-185-5p-GPX1 axis on AML progression and differentiation. Findings indicated that miR-185-5p and GPX1 levels were significantly reduced and elevated, respectively. The upregulation of miR-185-5p was observed to restrict the proliferation and invasion abilities of AML cells, and promote differentiate and apoptosis. Moreover, the overexpression of GPX1 was noticed to enhance the growth of AML cells. In conclusion, this research suggested that by targeting GPX1, miR-185-5p inhibited AML progression and downregulated AML cells' proliferation and invasion.

Sevoflurane inhibits progression of glioma via regulating the HMMR antisense RNA 1/microRNA-7/cyclin dependent kinase 4 axis

Sevoflurane (Sev) is a volatile anesthetic that can inhibit tumor malignancy. Glioma is a main brain problem, but the mechanism of Sev in glioma progression is largely unclear. This study aims to explore a potential regulatory network of long noncoding RNA (lncRNA)/microRNA (miRNA)/mRNA associated with the function of Sev in glioma progression. LncRNA HMMR antisense RNA 1 (HMMR-AS1), miR-7 and cyclin-dependent kinase 4 (CDK4) abundances were examined via quantitative reverse transcription polymerase chain reaction and western blot. Cell viability, invasion, and colony formation ability were analyzed via cell counting kit-8, transwell analysis, and colony formation. The target association was analyzed via dual-luciferase reporter analysis and RNA pull-down. The in vivo function of Sev was investigated by xenograft model. HMMR-AS1 abundance was increased in glioma tissues and cells, and reduced via Sev. Sev constrained cell viability, invasion, and colony formation ability via decreasing HMMR-AS1 in glioma cells. miR-7 expression was decreased in glioma, and was targeted via HMMR-AS1. HMMR-AS1 silence restrained cell viability, invasion, and colony formation ability by up-regulating miR-7 in glioma cells. Sev increases miR-7 abundance via decreasing HMMR-AS1. CDK4 was targeted via miR-7, and highly expressed in glioma. miR-7 overexpression inhibited cell viability, invasion, and colony formation ability via reducing CDK4 in glioma cells. CDK4 expression was reduced by Sev via HMMR-AS1/miR-7 axis. Sev suppressed cell growth in glioma by regulating HMMR-AS1. Sev represses glioma cell progression by regulating HMMR-AS1/miR-7/CDK4 axis.

Close interactions between lncRNAs, lipid metabolism and ferroptosis in cancer

Abnormal lipid metabolism including synthesis, uptake, modification, degradation and transport has been considered a hallmark of malignant tumors and contributes to the supply of substances and energy for rapid cell growth. Meanwhile, abnormal lipid metabolism is also associated with lipid peroxidation, which plays an important role in a newly discovered type of regulated cell death termed ferroptosis. Long noncoding RNAs (lncRNAs) have been proven to be associated with the occurrence and progression of cancer. Growing evidence indicates that lncRNAs are key regulators of abnormal lipid metabolism and ferroptosis in cancer. In this review, we mainly summarized the mechanism by which lncRNAs regulate aberrant lipid metabolism in cancer, illustrated that lipid metabolism can also influence the expression of lncRNAs, and discussed the mechanism by which lncRNAs affect ferroptosis. A comprehensive understanding of the interactions between lncRNAs, lipid metabolism and ferroptosis could help us to develop novel strategies for precise cancer treatment in the future.

Long noncoding RNA NORAD acts as a ceRNA mediates gemcitabine resistance in bladder cancer by sponging miR-155-5p to regulate WEE1 expression

BACKGROUND

Increasing evidences have proved that long noncoding RNAs (lncRNAs) regulate the occurrence of bladder cancer (BC) and participate in various pathophysiology processes. However, little is unknown about the role of lncRNAs in drug resistance of BC cells. In this study, we explored the role of non-coding RNA activated by DNA damage (NORAD) in the gemcitabine (GEM) resistant of BC cells and explored its potential mechanism.

METHODS

Real-time quantitative PCR (RT-qPCR) was used to detect the expression of NORAD and miR-155-5p of BC cells. Cell counting kit-8 (CCK-8) and Western blot were used to detect cell inhibition rate and the expression of WEE1 G2 checkpoint kinase (WEE1), P-glycoprotein (P-gp) and multidrug resistance-associated protein 1 (MRP1). Flow cytometry detected cell cycle and apoptosis. Dual luciferase reporter gene assay and RNA immunoprecipitation (RIP) assay were used to confirm the targeting relationship between miR-155-5p, NORAD and WEE1. The xenograft model was used to observe the function of NORAD in vivo. immunohistochemistry (IHC) assay was used to detect the expression of WEE1, caspase-3 and Ki67 in tumor tissues.

RESULTS

NORAD highly expressed in GEM-resistant BC cell lines. Knockdown of NORAD significantly inhibited the proliferation of T24/GEM cells, the expression of drug-resistant proteins P-gp and MRP1, inhibit the G0/G1 phase of cells, and induce cell apoptosis. Knockdown of NORAD reversed the promotion effect of miR-155-5p on WEE1 expression and promoted the sensitivity of T24/GEM cells to GEM. In vivo, knockdown of NORAD inhibited the tumor growth, and enhanced the GEM-sensitivity in mice.

CONCLUSION

These data highlight the potential of NORAD acts as a therapeutic target for BC GEM resistance. It revealed the vital roles of NORAD/miR-155-5p/WEE1 axis in GEM resistant BC cells, providing a novel therapeutic strategy for BC.

Role of long intergenic non-protein coding RNA 00152 in pancreatic cancer glycolysis via the manipulation of the microRNA-185-5p/Krüppel-like factor 7 axis

The current study set out to investigate the role of long intergenic non-protein coding RNA (LINC) 00152 in pancreatic cancer (PC) cell glycolysis with the microRNA (miR)-185-5p/Krüppel-like factor 7 (KLF7) axis. Firstly, PC tissues and cells as well as the control ones were collected from 53 PC patients, and assessed for LINC00152 expression patterns. Besides, PC cells with the most differentially expressed LINC00152 were selected for further experiments. When LINC00152 was silenced or overexpressed, PC cell glucose consumption, lactic acid production, adenosine triphosphate and levels of glycolysis-associated enzymes were detected. In addition, the binding relation between LINC00152 and miR-185-5p as well as the target relation between miR-185-5p and KLF7 was clarified and validated. Additionally, xenograft transplantation was performed to confirm the in vitro experiments. It was found that LINC00152 was over-expressed in PC, and it predicted a poor prognosis. Besides, LINC00152 knockdown inhibited PC cell glycolysis. Moreover, LINC00152 could specifically targeted miR-185-5p. Meanwhile, LINC00152 exhaustion blocked PC cell glycolysis through the up-regulation of miR-185-5p. Lastly, LINC00152 inhibition targeted miR-185-5p to quench KLF7, therefore suppressing PC cell tumorigenesis and glycolysis. Collectively, our findings indicated that silencing LINC00152 restricted PC cell glycolysis via promoting miR-185-5p and reducing KLF7.

Long noncoding RNA HAGLR sponges miR-338-3p to promote 5-Fu resistance in gastric cancer through targeting the LDHA-glycolysis pathway

Gastric cancer (GC) is one of the most common human malignancies due to its invasiveness and metastasis. 5‐Fu is a widely applied chemotherapeutic agent against GC. Although 5‐Fu therapy has achieved improvements in GC treatment, a large fraction of patients developed drug resistance which significantly limited its clinical applications. Recent studies revealed the pivotal roles of long noncoding RNAs (lncRNAs) in tumorigenesis and progressions of various tumors, including GC. However, the biological roles and molecular mechanisms of lncRNA HAGLR in GC remain unclear. Here, we report HAGLR was upregulated in both GC tissues and cell lines. In addition, HAGLR was associated with a poorly survival rate of GC patients. Blocking HAGLR inhibited GC cells proliferation and sensitized GC cells to 5‐Fu. Bioinformatical analysis and luciferase assay demonstrated that HAGLR sponged microRNA (miR)‐338‐3p, which functions as a tumor suppressor in GC to downregulate its expressions. Moreover, from the established 5‐Fu resistant GC cell line (HGC27 5‐Fu R), we detected significantly elevated HAGLR, downregulated miR‐338‐3p, and glucose metabolism compared with parental HGC27 cells. We identified lactate dehydrogenase‐A (LDHA), a glucose metabolism key enzyme, was the direct target of miR‐338‐3p in GC cells. Rescue experiments demonstrated that restoration of miR‐338‐3p in HAGLR‐overexpressing HGC27 5‐Fu R cells successfully overrode the HAGLR‐promoted 5‐Fu resistance through targeting LDHA. Taken together, this study revealed essential roles and molecular mechanisms for the HAGLR‐mediated 5‐Fu resistance in GC, contributing to the development of new noncoding RNA‐based therapeutic strategies against chemoresistant GC.

HAGLR promotes neuron differentiation through the miR-130a-3p-MeCP2 axis

Parkinson's disease (PD) is a prevalent neurodegenerative disease. Currently, the molecular mechanisms underlying the progressions of PD are not fully understood. The human neuroblastoma cell line SH-SY5Y has been widely used as an in vitro model for PD. This study aims to investigate the molecular mechanisms of the non-coding RNA-mediated SH-SY5Y differentiation induced by retinoic acid (RA). By microArray analysis, lncRNA HAGLR was observed to be significantly upregulated during the RA-induced SH-SY5Y differentiation. Silencing HAGLR blocked the RA-induced SH-SY5Y differentiation. Moreover, bioinformatical analysis illustrated that miR-130a-3p contains binding sites for HAGLR. The RNA-pull down assay and luciferase assay demonstrated that HAGLR functioned as a ceRNA of miR-130a-3p in SH-SY5Y cells. Overexpression of miR-130a-3p effectively inhibited SH-SY5Y differentiation. We identified MeCP2, a vital molecule in neuronal diseases, to be a direct target of miR-130a-3p in SH-SY5Y cells by western blot and luciferase assays. The rescue experiments verified that recovery of miR-130a-3p in HAGLR-overexpressing SH-SY5Y cells could successfully overcome the RA-induced SH-SY5Y differentiation by targeting MeCP2. In summary, this study reveals a potential molecular mechanism for the lncRNA-HAGLR-promoted in vitro neuron differentiation by targeting the miR-130a-3p-MeCP2 axis, contributing to the understanding of the pathogenesis and progression of PD.

Identification of a Four Hypoxia-Associated Long Non-Coding RNA Signature and Establishment of a Nomogram Predicting Prognosis of Clear Cell Renal Cell Carcinoma

To identify novel hypoxia-associated long non-coding RNAs (lncRNAs) as potential biomarkers, we developed a risk stratification signature and constructed a prognosis prediction nomogram of clear cell renal cell carcinoma (ccRCC). Hypoxia-related lncRNAs were identified through Pearson correlation analysis between the expression profiles of hypoxia-related differentially expressed genes and lncRNAs from The Cancer Genome Atlas Kidney Renal Clear Cell Carcinoma (TCGA-KIRC) dataset. Then, a signature of four key lncRNAs (COMETT, EMX2OS, AC026462.3, and HAGLR) was developed. The four lncRNAs were downregulated in high-grade, advanced stage, and high-risk ccRCC. The signature had an independent and long-standing prognosis prediction ability up to a 10-year follow-up. Notably, the risk score was significantly positively correlated with the infiltration abundances of six immune cells from the Tumor IMmune Estimation Resource (TIMER). The gene set enrichment analysis (GSEA) also suggested that the signature was involved in metabolism and tumorigenesis, which were closely related to the hypoxic tumor microenvironment. Ultimately, a nomogram of signature, age, stage, and grade, was built to predict the individual long-term survival possibility. Finally, the expressions of four lncRNAs were validated by quantitative real-time PCR (qRT-PCR). Our study identified a four-lncRNA signature and established a prognostic nomogram that reliably predicts survival in ccRCC. The findings may be beneficial to therapeutic customization and medical decision-making.

There and Back Again: Hox Clusters Use Both DNA Strands

Bilaterian animals operate the clusters of Hox genes through a rich repertoire of diverse mechanisms. In this review, we will summarize and analyze the accumulated data concerning long non-coding RNAs (lncRNAs) that are transcribed from sense (coding) DNA strands of Hox clusters. It was shown that antisense regulatory RNAs control the work of Hox genes in cis and trans, participate in the establishment and maintenance of the epigenetic code of Hox loci, and can even serve as a source of regulatory peptides that switch cellular energetic metabolism. Moreover, these molecules can be considered as a force that consolidates the cluster into a single whole. We will discuss the examples of antisense transcription of Hox genes in well-studied systems (cell cultures, morphogenesis of vertebrates) and bear upon some interesting examples of antisense Hox RNAs in non-model Protostomia.

Competing Endogenous RNA in Colorectal Cancer: An Analysis for Colon, Rectum, and Rectosigmoid Junction

BACKGROUND

Colorectal cancer (CRC) is a heterogeneous cancer. Its treatment depends on its anatomical site and distinguishes between colon, rectum, and rectosigmoid junction cancer. This study aimed to identify diagnostic and prognostic biomarkers using networks of CRC-associated transcripts that can be built based on competing endogenous RNAs (ceRNA).

METHODS

RNA expression and clinical information data of patients with colon, rectum, and rectosigmoid junction cancer were obtained from The Cancer Genome Atlas (TCGA). The RNA expression profiles were assessed through bioinformatics analysis, and a ceRNA was constructed for each CRC site. A functional enrichment analysis was performed to assess the functional roles of the ceRNA networks in the prognosis of colon, rectum, and rectosigmoid junction cancer. Finally, to verify the ceRNA impact on prognosis, an overall survival analysis was performed.

RESULTS

The study identified various CRC site-specific prognosis biomarkers: hsa-miR-1271-5p, NRG1, hsa-miR-130a-3p, SNHG16, and hsa-miR-495-3p in the colon; E2F8 in the rectum and DMD and hsa-miR-130b-3p in the rectosigmoid junction. We also identified different biological pathways that highlight differences in CRC behavior at different anatomical sites, thus reinforcing the importance of correctly identifying the tumor site.

CONCLUSIONS

Several potential prognostic markers for colon, rectum, and rectosigmoid junction cancer were found. CeRNA networks could provide better understanding of the differences between, and common factors in, prognosis of colon, rectum, and rectosigmoid junction cancer.

Predictive Efficacy of MiR-125b-5p, MiR-17-5p, and MiR-185-5p in Liver Metastasis and Chemotherapy Response Among Advanced Stage Colorectal Cancer Patients

MicroRNAs (miRNAs), a class of small non-coding RNAs represent potential biomarkers for colorectal cancer (CRC). The study hypothesized that miRNAs associated with liver metastases may also contribute to assessing treatment response when associated to plasma exosomes. In this study, we used two sets of biological samples, a collection of tumor tissues harvested from patients with CRC with and without liver metastases, and a collection of plasma from CRC patients with and without response to FOLFOX4/FOLFIRI regimens. We investigated 10 target miRNAs in the tissue of 28 CRC patients and identified miR-125b-5p, miR-17-5p, and miR-185-5p to be associated with liver metastasis. Further, we investigated the three miRNAs at the exosomal level in a plasma collection to test their association with chemotherapy response. Our data suggest that the elevated plasma levels of miR-17-5p and miR-185-5p could be predictive of treatment response. Overexpression of miR-17-5p and underexpression of miR-125b-5p and miR-185-5p in CRC tissue seem to be associated with metastatic potential. On the other hand, an increased expression of miR-125b-5p in plasma exosomes was potentially correlated with a more aggressive CRC phenotype.

LncRNA MSC-AS1 Promotes Colorectal Cancer Progression by Regulating miR-325/TRIM14 Axis

Background

LncRNA MSC-AS1 has been reported to be a tumor promoter in hepatocellular carcinoma. However, the function of MSC-AS1 in colorectal cancer (CRC) has not been elucidated. It is designed to study the expression level of MSC-AS1 and investigate its biological effect on the progression of CRC.

Methods

The expression patterns of MSC-AS1, miR-325, and TRIM14 were explored by RT-qPCR in CRC tissues and cells. The protein expression of TRIM14 was tested by Western blot assay. The association between MSC-AS1 expression and clinicopathological data was analyzed by chi-squared test. CCK-8 assay, colony formation, and Transwell assay were used to investigate the effect of MSC-AS1 on cell growth, invasion, and migration in CRC cells. The correlations among MSC-AS1, miR-325, and TRIM14 were analyzed by Pearson's correlation coefficient analysis.

Results

We found that MSC-AS1 and TRIM14 were upregulated in CRC tissues, while miR-325 was downregulated in CRC tissues. Functional experiments demonstrated that MSC-AS1 knockdown inhibited cell proliferation, migration, and invasion abilities in CRC cells. Additionally, miR-325 was proved to be a target miRNA of MSC-AS1, and TRIM14 might be a downstream gene of miR-325. Besides that, MSC-AS1 counteracted the inhibitory effect of miR-325 on the cell progression and TRIM14 expression.

Conclusion

Our results indicated that MSC-AS1 facilitated CRC progression by sponging miR-325 to upregulate TRIM14 expression. We suggested that MSC-AS1 might be a potential lncRNA-target for CRC therapy.

Identification of long non-coding RNA signatures for squamous cell carcinomas and adenocarcinomas

Studies have demonstrated that both squamous cell carcinomas (SCCs) and adenocarcinomas (ACs) possess some common molecular characteristics. Evidence has accumulated to support the theory that long non-coding RNAs (lncRNAs) serve as novel biomarkers and therapeutic targets in complex diseases such as cancer.

In this study, we aimed to identify pan lncRNA signatures that are common to squamous cell carcinomas or adenocarcinomas with different tissues of origin. With the aid of elastic-net regularized regression models, a 35-lncRNA pan discriminative signature and an 11-lncRNA pan prognostic signature were identified for squamous cell carcinomas, whereas a 6-lncRNA pan discriminative signature and a 5-lncRNA pan prognostic signature were identified for adenocarcinomas. Among them, many well-known cancer relevant genes such as MALAT1 and PVT1 were included.

The identified pan lncRNA lists can help experimental biologists generate research hypotheses and adopt existing treatments for less prevalent cancers. Therefore, these signatures warrant further investigation.

Current mechanisms in obesity and tumor progression

PURPOSE OF REVIEW

Hyperadiposity, as present in obesity, is a substantial threat to cancer risk and prognosis. Studies that have investigated the link between obesity and tumor progression have proposed several mechanistic frameworks, yet, these mechanisms are not fully defined. Further, a comprehensive understanding of how these various mechanisms may interact to create a dynamic disease state is lacking in the current literature.

RECENT FINDINGS

Recent work has begun to explore not only discrete mechanisms by which obesity may promote tumor growth (for instance, metabolic and growth factor functions of insulin; inflammatory cytokines; adipokines; and others), but also how these putative tumor-promoting factors may interact.

SUMMARY

This review will highlight the present understanding of obesity, as it relates to tumor development and progression. First, we will introduce the impact of obesity in cancer within the dynamic tumor microenvironment, which will serve as a theme to frame this review. The core of this review will discuss recently proposed mechanisms that implicate obesity in tumor progression, including chronic inflammation and the role of pro-inflammatory cytokines, adipokines, hormones, and genetic approaches. Furthermore, we intend to offer current insight in targeting adipose tissue during the development of cancer prevention and treatment strategies.

lncRNA RP11-624L4.1 Is Associated with Unfavorable Prognosis and Promotes Proliferation via the CDK4/6-Cyclin D1-Rb-E2F1 Pathway in NPC

Nasopharyngeal carcinoma (NPC) is one of the most common malignant tumors in southern China and southeast Asia. Emerging evidence revealed that long noncoding RNAs (lncRNAs) might play important roles in the development and progression of many cancers, including NPC. The functions and mechanisms of the vast majority of lncRNAs involved in NPC remain unknown. In this study, a novel lncRNA RP11-624L4.1 was identified in NPC tissues using next-generation sequencing. In situ hybridization (ISH) was used to analyze the correlation between RP11-624L4.1 expression and the clinicopathological features or prognosis in NPC patients. RNA-Protein Interaction Prediction (RPISeq) predictions and RNA-binding protein immunoprecipitation (RIP) assays were used to identify RP11-624L4.1's interactions with cyclin-dependent kinase 4 (CDK4). As a result, we found that RP11-624L4.1 is hyper-expressed in NPC tissues, which was associated with unfavorable prognosis and clinicopathological features in NPC. By knocking down and overexpressing RP11-624L4.1, we also found that it promotes the proliferation ability of NPC in vitro and in vivo through the CDK4/6-Cyclin D1-Rb-E2F1 pathway. Overexpression of CDK4 in knocking down RP11-624L4.1 cells can partially rescue NPC promotion, indicating its role in the RP11-624L4.1-CDK4/6-Cyclin D1-Rb-E2F1 pathway. Taken together, RP11-624L4.1 is required for NPC unfavorable prognosis and proliferation through the CDK4/6-Cyclin D1-Rb-E2F1 pathway, which may be a novel therapeutic target and prognostic in patients with NPC.