LINC00857 Interacting with YBX1 to Regulate Apoptosis and Autophagy via MET and Phosphor-AMPKa Signaling

LncRNAs are involved in regulating ageing and age-related disease through the adenosine monophosphate-activated protein kinase signalling pathway

A long noncoding RNA (lncRNA) is longer than 200 bp. It regulates various biological processes mainly by interacting with DNA, RNA, or protein in multiple kinds of biological processes. Adenosine monophosphate-activated protein kinase (AMPK) is activated during nutrient starvation, especially glucose starvation and oxygen deficiency (hypoxia), and exposure to toxins that inhibit mitochondrial respiratory chain complex function. AMPK is an energy switch in organisms that controls cell growth and multiple cellular processes, including lipid and glucose metabolism, thereby maintaining intracellular energy homeostasis by activating catabolism and inhibiting anabolism. The AMPK signalling pathway consists of AMPK and its upstream and downstream targets. AMPK upstream targets include proteins such as the transforming growth factor β-activated kinase 1 (TAK1), liver kinase B1 (LKB1), and calcium/calmodulin-dependent protein kinase β (CaMKKβ), and its downstream targets include proteins such as the mechanistic/mammalian target of rapamycin (mTOR) complex 1 (mTORC1), hepatocyte nuclear factor 4α (HNF4α), and silencing information regulatory 1 (SIRT1). In general, proteins function relatively independently and cooperate. In this article, a review of the currently known lncRNAs involved in the AMPK signalling pathway is presented and insights into the regulatory mechanisms involved in human ageing and age-related diseases are provided.

Developing a prognostic model using machine learning for disulfidptosis related lncRNA in lung adenocarcinoma

Disulfidptosis represents a novel cell death mechanism triggered by disulfide stress, with potential implications for advancements in cancer treatments. Although emerging evidence highlights the critical regulatory roles of long non-coding RNAs (lncRNAs) in the pathobiology of lung adenocarcinoma (LUAD), research into lncRNAs specifically associated with disulfidptosis in LUAD, termed disulfidptosis-related lncRNAs (DRLs), remains insufficiently explored. Using The Cancer Genome Atlas (TCGA)-LUAD dataset, we implemented ten machine learning techniques, resulting in 101 distinct model configurations. To assess the predictive accuracy of our model, we employed both the concordance index (C-index) and receiver operating characteristic (ROC) curve analyses. For a deeper understanding of the underlying biological pathways, we referred to the Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) for functional enrichment analysis. Moreover, we explored differences in the tumor microenvironment between high-risk and low-risk patient cohorts. Additionally, we thoroughly assessed the prognostic value of the DRLs signatures in predicting treatment outcomes. The Kaplan-Meier (KM) survival analysis demonstrated a significant difference in overall survival (OS) between the high-risk and low-risk cohorts (p < 0.001). The prognostic model showed robust performance, with an area under the ROC curve exceeding 0.75 at one year and maintaining a value above 0.72 in the two and three-year follow-ups. Further research identified variations in tumor mutational burden (TMB) and differential responses to immunotherapies and chemotherapies. Our validation, using three GEO datasets (GSE31210, GSE30219, and GSE50081), revealed that the C-index exceeded 0.67 for GSE31210 and GSE30219. Significant differences in disease-free survival (DFS) and OS were observed across all validation cohorts among different risk groups. The prognostic model offers potential as a molecular biomarker for LUAD prognosis.

The prognostic value of sialylation-related long non-coding RNAs in lung adenocarcinoma

There has been increasing interest in the role of epigenetic modification in cancers recently. Among the various modifications, sialylation has emerged as a dominant subtype implicated in tumor progression, metastasis, immune evasion, and chemoresistance. The prognostic significance of sialylation-related molecules has been demonstrated in colorectal cancer. However, the potential roles and regulatory mechanisms of sialylation in lung adenocarcinoma (LUAD) have not been thoroughly investigated. Through Pearson correlation, univariate Cox hazards proportional regression, and random survival forest model analyses, we identified several prognostic long non-coding RNAs (lncRNAs) associated with aberrant sialylation and tumor progression, including LINC00857, LINC00968, LINC00663, and ITGA9-AS1. Based on the signatures of four lncRNAs, we classified patients into two clusters with different landscapes using a non-negative matrix factorization approach. Collectively, patients in Cluster 1 (C1) exhibited worse prognoses than those in Cluster 2 (C2), as well as heavier tumor mutation burden. Functional enrichment analysis showed the enrichment of several pro-tumor pathways in C1, differing from the upregulated Longevity and programmed cell death pathways in C2. Moreover, we profiled immune infiltration levels of important immune cell lineages in two subgroups using MCPcounter scores and single sample gene set enrichment analysis scores, revealing a relatively immunosuppressive microenvironment in C1. Risk analysis indicated that LINC00857 may serve as a pro-tumor regulator, while the other three lncRNAs may be protective contributors. Consistently, we observed upregulated LINC00857 in C1, whereas increased expressive levels of LINC00968, LINC00663, and ITGA9-AS1 were observed in C2. Finally, drug sensitivity analysis suggested that patients in the two groups may benefit from different therapeutic strategies, contributing to precise treatment in LUAD. By integrating multi-omics data, we identified four core sialylation-related lncRNAs and successfully established a prognostic model to distinguish patients with different characterizations. These findings may provide some insights into the underlying mechanism of sialylation, and offer a new stratification way as well as clinical guidance in LUAD.

Modulation of YBX1-mediated PANoptosis inhibition by PPM1B and USP10 confers chemoresistance to oxaliplatin in gastric cancer

Gastric cancer (GC) is a common malignant tumor of the digestive tract, and chemoresistance significantly impacts GC patients' prognosis. PANoptosis has been associated with oxaliplatin-induced cell death. However, the direct regulatory role of YBX1 in cellular chemoresistance through PANoptosis remains unclear. In this study, we investigated the impact of YBX1 on regulating PANoptosis and its influence on the resistance of gastric cancer cells to oxaliplatin. Through overexpression and silencing experiments, we assessed YBX1's effect on proliferation and PANoptosis regulation in gastric cancer cells. Additionally, we identified PPM1B and USP10 as interacting proteins with YBX1 and confirmed their influence on YBX1 molecular function and protein expression levels. Our results demonstrate that YBX1 suppresses PANoptosis, leading to enhanced resistance of gastric cancer cells to oxaliplatin. Furthermore, we found that PPM1B and USP10 play critical roles in regulating YBX1-mediated PANoptosis inhibition. PPM1B directly interacts with YBX1, causing dephosphorylation of YBX1 at serine 314 residue. This dephosphorylation process affects the deubiquitination of YBX1 mediated by USP10, resulting in decreased YBX1 protein expression levels and impacting PANoptosis and oxaliplatin resistance in gastric cancer cells. Additionally, we discovered that the 314th amino acid of YBX1 has a profound impact on its own protein expression abundance, thereby affecting the functionality of YBX1. In conclusion, our study reveals the significance of PPM1B-mediated dephosphorylation of YBX1 and USP10-mediated deubiquitination in regulating PANoptosis and sensitivity to oxaliplatin in gastric cancer cells. These findings offer a potential therapeutic strategy for patients with oxaliplatin-resistant gastric cancer.

Y-Box Binding Protein 1: Unraveling the Multifaceted Role in Cancer Development and Therapeutic Potential

Y-box binding protein 1 (YBX1), a member of the Cold Shock Domain protein family, is overexpressed in various human cancers and is recognized as an oncogenic gene associated with poor prognosis. YBX1's functional diversity arises from its capacity to interact with a broad range of DNA and RNA molecules, implicating its involvement in diverse cellular processes. Independent investigations have unveiled specific facets of YBX1's contribution to cancer development. This comprehensive review elucidates YBX1's multifaceted role in cancer across cancer hallmarks, both in cancer cell itself and the tumor microenvironment. Based on this, we proposed YBX1 as a potential target for cancer treatment. Notably, ongoing clinical trials addressing YBX1 as a target in breast cancer and lung cancer have showcased its promise for cancer therapy. The ramp up in in vitro research on targeting YBX1 compounds also underscores its growing appeal. Moreover, the emerging role of YBX1 as a neural input is also proposed where the high level of YBX1 was strongly associated with nerve cancer and neurodegenerative diseases. This review also summarized the up-to-date advanced research on the involvement of YBX1 in pancreatic cancer.

Kaempferol promotes non-small cell lung cancer cell autophagy via restricting Met pathway

BACKGROUND

Kaempferol is extracted from Hedyotis diffusa, exerting an obvious anti-cancer effect. Here in the present study, we explored the anti-cancer effects and mechanism of kaempferol in non-small cell lung cancer cell (NSCLC).

PURPOSE

Our objective is to figure out the molecular mechanism by which kaempferol promotes autophagy in NSCLC cells.

STUDY DESIGN

A549 and H1299 NSCLC cell lines were used for in vitro experiments. And BALB/c nude mice of NSCLC were used to perform in vivo experiments.

METHODS

For in vitro experiments, CCK-8 and EdU assay was used to observe the effect of kaempferol on NSCLC cell proliferation. Confocal microscopy of mCherry-EGFR-LC3 assay and electron microscopy assay were used to detect NSCLC cell autophagy. Protein expression was determined using Western blot, and mRNA expression was determined using qRT-PCR. Flow cytometry was performed to detect the cell apoptosis. For in vivo experiments, a subcutaneously implanted tumor model in BALB/C nude mice was performed using human NSCLC cell line A549-Luc. The kaempferol effect on NSCLC mice model was detected by measuring the tumor weight and bioluminescence intensity. Immunohistochemistry was done to measure the key protein expression from mice tumor tissues.

RESULTS

Our results confirmed that kaempferol inhibited NSCLC cell proliferation significantly. And it promoted NSCLC cell autophagy, leading to NSCLC cell death. Interestingly, Met-was greatly inhibited at both protein and mRNA levels. Meanwhile, PI3K/AKT/mTOR signaling pathway was inhibited accordingly. Furthermore, overexpressing Met-reversed the effect of kaempferol on NSCLC cell viability and cell autophagy with significance. Finally, the above effect and pathway were validated using the xenograft model.

CONCLUSION

Kaempferol may exert its anti-NSCLC effect by promoting NSCLC cell autophagy. Mechanistically, Met-and its downstream PI3K/AKT/mTOR signaling pathway were involved in the process, which provides a novel mechanism how kaempferol functions in inhibiting NSCLC.

Therapeutic strategies targeting AMPK-dependent autophagy in cancer cells

Macroautophagy is a health-modifying process of engulfing misfolded or aggregated proteins or damaged organelles, coating these proteins or organelles into vesicles, fusion of vesicles with lysosomes to form autophagic lysosomes, and degradation of the encapsulated contents. It is also a self-rescue strategy in response to harsh environments and plays an essential role in cancer cells. AMP-activated protein kinase (AMPK) is the central pathway that regulates autophagy initiation and autophagosome formation by phosphorylating targets such as mTORC1 and unc-51 like activating kinase 1 (ULK1). AMPK is an evolutionarily conserved serine/threonine protein kinase that acts as an energy sensor in cells and regulates various metabolic processes, including those involved in cancer. The regulatory network of AMPK is complicated and can be regulated by multiple upstream factors, such as LKB1, AKT, PPAR, SIRT1, or noncoding RNAs. Currently, AMPK is being investigated as a novel target for anticancer therapies based on its role in macroautophagy regulation. Herein, we review the effects of AMPK-dependent autophagy on tumor cell survival and treatment strategies targeting AMPK.

Unravelling the complexity of lncRNAs in autophagy to improve potential cancer therapy

Autophagy is well-known as an internal catabolic process that is evolutionarily conserved and performs the key biological function in maintaining cellular homeostasis. It is tightly controlled by several autophagy-related (ATG) proteins, which are closely associated with many types of human cancers. However, what has remained controversial is the janus roles of autophagy in cancer progression. Interestingly, the biological function of long non-coding RNAs (lncRNAs) in autophagy has been gradually understood in different types of human cancers. More recently, numerous studies have demonstrated that several lncRNAs may regulate some ATG proteins and autophagy-related signaling pathways to either activate or inhibit the autophagic process in cancer. Thus, in this review, we summarize the latest advance in the knowledge of the complicated relationships between lncRNAs and autophagy in cancer. Also, the in-depth dissection of the lncRNAs-autophagy-cancers axis involved in this review would shed new light on discovery of more potential cancer biomarkers and therapeutic targets in the future.

Functions, mechanisms, and clinical applications of lncRNA LINC00857 in cancer pathogenesis

Emerging data indicated that long noncoding RNAs (lncRNAs) are crucial players in the biological processes via regulating epigenetics, transcription, and protein translation. A novel lncRNA, LINC00857, was indicated to upregulate in several types of cancer. In addition, LINC00857 was functionally related to the modulation of the cancer-linked behaviors, including invasion, migration, proliferation, epithelial-mesenchymal transition (EMT), cell cycle, and apoptosis. The importance of LINC00857 in cancer onset and development proposed that LINC00857 has major importance in the cancer progression and may be considered as a novel prognostic/diagnostic biomarker as well as a treatment target. Here, we retrospectively investigate the available progress in biomedical research investigating the functions of LINC00857 in cancer, focusing on finding the molecular mechanisms affecting various cancer-related behaviors and exploring its clinical applications.

Long non-coding RNAs in non-small cell lung cancer: implications for EGFR-TKI resistance

Non-small cell lung cancer (NSCLC) is one of the most common types of malignant tumors as well as the leading cause of cancer-related deaths in the world. The application of epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) has dramatically improved the prognosis of NSCLC patients who harbor EGFR mutations. However, despite an excellent initial response, NSCLC inevitably becomes resistant to EGFR-TKIs, leading to irreversible disease progression. Hence, it is of great significance to shed light on the molecular mechanisms underlying the EGFR-TKI resistance in NSCLC. Long non-coding RNAs (lncRNAs) are critical gene modulators that are able to act as oncogenes or tumor suppressors that modulate tumorigenesis, invasion, and metastasis. Recently, extensive evidence demonstrates that lncRNAs also have a significant function in modulating EGFR-TKI resistance in NSCLC. In this review, we present a comprehensive summary of the lncRNAs involved in EGFR-TKI resistance in NSCLC and focus on their detailed mechanisms of action, including activation of alternative bypass signaling pathways, phenotypic transformation, intercellular communication in the tumor microenvironment, competing endogenous RNAs (ceRNAs) networks, and epigenetic modifications. In addition, we briefly discuss the limitations and the clinical implications of current lncRNAs research in this field.

Biological insights in non-small cell lung cancer

Lung oncogenesis relies on intracellular cysteine to overcome oxidative stress. Several tumor types, including non-small cell lung cancer (NSCLC), upregulate the system xc- cystine/glutamate antiporter (xCT) through overexpression of the cystine transporter SLC7A11, thus sustaining intracellular cysteine levels to support glutathione synthesis. Nuclear factor erythroid 2-related factor 2 (NRF2) serves as a master regulator of oxidative stress resistance by regulating SLC7A11, whereas Kelch-like ECH-associated protein (KEAP1) acts as a cytoplasmic repressor of the oxidative responsive transcription factor NRF2. Mutations in KEAP1/NRF2 and p53 induce SLC7A11 activation in NSCLC. Extracellular cystine is crucial in supplying the intracellular cysteine levels necessary to combat oxidative stress. Disruptions in cystine availability lead to iron-dependent lipid peroxidation, thus resulting in a type of cell death called ferroptosis. Pharmacologic inhibitors of xCT (either SLC7A11 or GPX4) induce ferroptosis of NSCLC cells and other tumor types. When cystine uptake is impaired, the intracellular cysteine pool can be sustained by the transsulfuration pathway, which is catalyzed by cystathionine-B-synthase (CBS) and cystathionine g-lyase (CSE). The involvement of exogenous cysteine/cystine and the transsulfuration pathway in the cysteine pool and downstream metabolites results in compromised CD8+ T cell function and evasion of immunotherapy, diminishing immune response and potentially reducing the effectiveness of immunotherapeutic interventions. Pyroptosis is a previously unrecognized form of regulated cell death. In NSCLCs driven by EGFR, ALK, or KRAS, selective inhibitors induce pyroptotic cell death as well as apoptosis. After targeted therapy, the mitochondrial intrinsic apoptotic pathway is activated, thus leading to the cleavage and activation of caspase-3. Consequently, gasdermin E is activated, thus leading to permeabilization of the cytoplasmic membrane and cell-lytic pyroptosis (indicated by characteristic cell membrane ballooning). Breakthroughs in KRAS G12C allele-specific inhibitors and potential mechanisms of resistance are also discussed herein.

Targeting Autophagy Using Long Non-Coding RNAs (LncRNAs): New Landscapes in the Arena of Cancer Therapeutics

Cancer has become a global health hazard accounting for 10 million deaths in the year 2020. Although different treatment approaches have increased patient overall survival, treatment for advanced stages still suffers from poor clinical outcomes. The ever-increasing prevalence of cancer has led to a reanalysis of cellular and molecular events in the hope to identify and develop a cure for this multigenic disease. Autophagy, an evolutionary conserved catabolic process, eliminates protein aggregates and damaged organelles to maintain cellular homeostasis. Accumulating evidence has implicated the deregulation of autophagic pathways to be associated with various hallmarks of cancer. Autophagy exhibits both tumor-promoting and suppressive effects based on the tumor stage and grades. Majorly, it maintains the cancer microenvironment homeostasis by promoting viability and nutrient recycling under hypoxic and nutrient-deprived conditions. Recent investigations have discovered long non-coding RNAs (lncRNAs) as master regulators of autophagic gene expression. lncRNAs, by sequestering autophagy-related microRNAs, have been known to modulate various hallmarks of cancer, such as survival, proliferation, EMT, migration, invasion, angiogenesis, and metastasis. This review delineates the mechanistic role of various lncRNAs involved in modulating autophagy and their related proteins in different cancers.

Current and potential roles of RNA modification-mediated autophagy dysregulation in cancer

Autophagy, a cellular lysosomal degradation and survival pathway, supports nutrient recycling and adaptation to metabolic stress and participates in various stages of tumor development, including tumorigenesis, metastasis, and malignant state maintenance. Among the various factors contributing to the dysregulation of autophagy in cancer, RNA modification can regulate autophagy by directly affecting the expression of core autophagy proteins. We propose that autophagy disorder mediated by RNA modification is an important mechanism for cancer development. Therefore, this review mainly discusses the role of RNA modification-mediated autophagy regulation in tumorigenesis. We summarize the molecular basis of autophagy and the core proteins and complexes at different stages of autophagy, especially those involved in cancer development. Moreover, we describe the crosstalk of RNA modification and autophagy and review the recent advances and potential role of the RNA modification/autophagy axis in the development of multiple cancers. Furthermore, the dual role of the RNA modification/autophagy axis in cancer drug resistance is discussed. A comprehensive understanding and extensive exploration of the molecular crosstalk of RNA modifications with autophagy will provide important insights into tumor pathophysiology and provide more options for cancer therapeutic strategies.

Transcriptional and post-transcriptional control of autophagy and adipogenesis by YBX1

Obesity is strongly associated with metabolic diseases, which have become a global health problem. Exploring the underlying mechanism of adipogenesis is crucial for the treatment of excess white fat. Oncogene YBX1 is a multifunctional DNA- and RNA-binding protein that regulates brown adipogenesis. However, the role of YBX1 in white adipogenesis and adipose tissue expansion remains unknown. Here, we showed that YBX1 deficiency inhibited murine and porcine adipocyte differentiation. YBX1 positively regulated adipogenesis through promoting ULK1- and ULK2-mediated autophagy. Mechanistically, we identified YBX1 serves as a 5-methylcytosine (m⁵C)-binding protein directly targeting m⁵C-containing Ulk1 mRNA by using RNA immunoprecipitation. RNA decay assay further proved that YBX1 upregulated ULK1 expression though stabilizing its mRNA. Meanwhile, YBX1 promoted Ulk2 transcription and expression as a transcription factor, thereby enhancing autophagy and adipogenesis. Importantly, YBX1 overexpression in white fat enhanced ULK1/ULK2-mediated autophagy and promoted adipose tissue expansion in mice. Collectively, these findings unveil the post-transcriptional and transcriptional mechanism and functional importance of YBX1 in autophagy and adipogenesis regulation, providing an attractive molecular target for therapies of obesity and metabolic diseases.

The role of biomarkers in stage III non-small cell lung cancer

INTRODUCTION

Stage III non-small cell lung cancer (NSCLC) is a composite of the regional spread of lung cancer with different levels of potential lymph node involvement and tumor size that often deem the stage at time of diagnosis to be unresectable and suitable for chemoradiation plus consolidation immunotherapy with durvalumab for 12 months. Chemoradiation plus durvalumab consolidation yielded a landmark 49.2% 5-year overall survival in unresectable NSCLC.

AREAS COVERED

Sub-optimal results lead us to focus on the mechanisms of resistance responsible for intractability in a significant proportion of cases that fail with chemoradiation and immunotherapy. In stage III NSCLC it is opportune to explore the accumulated evidence on ferroptosis resistance that can lead to cancer progression and metastasis. Strong data shows that three anti-ferroptosis pathways are principally involved in resistance to chemotherapy, radiation, and immunotherapy.

EXPERT OPINION

Because a large part of stage III NSCLCs is resistant to chemoradiation and durvalumab consolidation, a ferroptosis-based therapeutic approach, combined with standard-of-care therapy, can lead to improved clinical outcomes in patients diagnosed with stage III and possibly stage IV NSCLCs.

Mutant p53 driven-LINC00857, a protein scaffold between FOXM1 and deubiquitinase OTUB1, promotes the metastasis of pancreatic cancer

Tumour metastasis is the major adverse factor for recurrence and death in pancreatic cancer (PC) patients. P53 mutations are considered to be the second most common type of mutation in PC and significantly promote PC metastasis. However, the molecular mechanisms underlying the effects of p53 mutations, especially the regulatory relationship of the protein with long noncoding RNAs (lncRNAs), remain unclear. In the present study, we demonstrated that the lncRNA LINC00857 exhibits a significantly elevated level in PC and that it is associated with poor prognosis; furthermore, TCGA data showed that LINC00857 expression was significantly upregulated in the mutant p53 group compared with the wild-type p53 group. Gain- and loss-of-function experiments showed that LINC00857 promotes the metastasis of PC cells. We further found that LINC00857 upregulates FOXM1 protein expression and thus accelerates metastasis in vitro and in vivo. Mechanistically, LINC00857 bound simultaneously to FOXM1 and to the deubiquitinase OTUB1, thereby serving as a protein scaffold and enhancing the interaction between FOXM1 and OTUB1, which inhibits FOXM1 degradation through the ubiquitin-proteasome pathway. Interestingly, we found that mutant p53 promotes LINC00857 transcription by binding to its promoter region. Finally, atorvastatin, a commonly prescribe lipid-lowering drug, appeared to inhibit PC metastasis by inhibiting the mutant p53-LINC00857 axis. Taken together, our results provide new insights into the biology driving PC metastasis and indicate that the mutant p53-LINC00857 axis might represent a novel therapeutic target for PC metastasis.

Macrophage Sprouty4 deficiency diminishes sepsis-induced acute lung injury in mice

OBJECTIVE

Inflammation and oxidative stress play critical roles in sepsis-induced acute lung injury (ALI). Sprout4 (Spry4) is involved in regulating inflammation and tissue injury; however, its role and mechanism in sepsis-induced ALI remain elusive.

METHODS

Macrophage-specific Spry4 knockout (Spry4^MKO), transgenic (Spry4^MTG) mice and matched control littermates were generated and exposed to cecum ligation and puncture (CLP) surgery to establish bacterial sepsis-induced ALI. Bone marrow-derived macrophages (BMDMs) from Spry4^MKO or Spry4^MTG mice were isolated and subjected to lipopolysaccharide (LPS) stimulation to further validate the role of Spry4 in vitro. To verify the necessity of AMP-activated protein kinase (AMPK), Spry4 and AMPK double knockout mice and compound C were used in vivo and in vitro. BMDMs were treated with STO-609 to inhibit calcium/calmodulin-dependent protein kinase kinase 2 (CaMKK2).

RESULTS

We found that macrophage Spry4 was increased in CLP mice and positively correlated with sepsis-induced ALI. Macrophage Spry4 deficiency prevented, while macrophage Spry4 overexpression exacerbated sepsis-induced inflammation, oxidative stress and ALI in mice and BMDMs. Mechanistic studies revealed that macrophage Spry4 deficiency alleviated sepsis-induced ALI through activating CaMKK2/AMPK pathway.

CONCLUSION

Our study identify macrophage Spry4 as a promising predictive and therapeutic target of sepsis-induced ALI.

Construction and analysis of expression profile of exosomal lncRNAs in pleural effusion in lung adenocarcinoma

BACKGROUND

Lung adenocarcinoma (LUAD) is a highly malignant tumor with a very low five-year survival rate. In this study, we aimed to identify differentially expressed long-chain non-coding RNA (lncRNAs) and mRNAs from benign and malignant pleural effusion exosomes.

METHODS

We used gene microassay and quantitative real-time reverse transcription polymerase chain reaction (RT-qPCR) to detect and verify differentially expressed mRNAs and lncRNAs in benign and malignant pleural effusion exosomes. Gene Ontology (GO) functional significance and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway significance enrichment analyses were performed to identify the difference in biological processes and functions between different mRNAs. We selected the lncRNA ZBED5-AS1 with an upregulated differential fold of 3.003 and conducted a preliminary study on its cellular function.

RESULTS

Gene microassay results revealed that 177 differentially expressed lncRNAs were upregulated, and 215 were downregulated. The top 10 upregulated were FMN1, AL118505.1, LINC00452, AL109811.2, CATG00000040683.1, AC137932.1, AC008619.1, AL450344.1, AC092718.6, and ZBED5-AS1. The top 10 downregulated were TEX41, G067726, JAZF1-AS1, AC027328.1, AL445645.1, AL022345.4, AC008572.1, AC123777.1, AC093714.1, and PHKG1. For the mRNAs, 79 were upregulated, and 123 were notably downregulated. GO analysis revealed that the upregulated differential mRNAs were mainly involved in "cellular response to acidic pH" (biological processes), "endoplasmic reticulum part" (cellular components), and "at DNA binding, cyclase activity" (molecular functions). KEGG pathways were found to be related to V. cholerae infection, Parkinson's disease, and cell adhesion molecules. RT-qPCR showed that ZBED5-AS1 was highly expressed in LUAD tissues, cells, and benign and malignant pleural fluid exosomes. Overexpression of ZBED5-AS1 could significantly promote the proliferation, migration, invasion, and colony formation of LUAD cells, and knockdown had the opposite consequence.

CONCLUSION

The pleural effusion exosomes from patients with LUAD include several improperly expressed genes, and lncRNA-ZBED5-AS1 is a new biomarker that aids in our understanding of the occurrence and progression of LUAD.

Identification of a apoptosis-related LncRNA signature to improve prognosis prediction and immunotherapy response in lung adenocarcinoma patients

Apoptosis is closely associated with the development of various cancers, including lung adenocarcinoma (LUAD). However, the prognostic value of apoptosis-related lncRNAs (ApoRLs) in LUAD has not been fully elucidated. In the present study, we screened 2, 960 ApoRLs by constructing a co-expression network of mRNAs-lncRNAs associated with apoptosis, and identified 421 ApoRLs that were differentially expressed between LUAD samples and normal lung samples. Sixteen differentially expressed apoptosis-related lncRNAs (DE-ApoRLs) with prognostic relevance to LUAD patients were screened using univariate Cox regression analysis. An apoptosis-related lncRNA signature (ApoRLSig ) containing 10 ApoRLs was constructed by applying the Least Absolute Shrinkage and Selection Operator (LASSO) Cox regression method, and all LUAD patients in the TCGA cohort were divided into high or low risk groups. Moreover, patients in the high-risk group had a worse prognosis (p < 0.05). When analyzed in conjunction with clinical features, we found ApoRLSig to be an independent predictor of LUAD patients and established a prognostic nomogram combining ApoRLSig and clinical features. Gene set enrichment analysis (GSEA) revealed that ApoRLSig is involved in many malignancy-associated immunomodulatory pathways. In addition, there were significant differences in the immune microenvironment and immune cells between the high-risk and low-risk groups. Further analysis revealed that the expression levels of most immune checkpoint genes (ICGs) were higher in the high-risk group, which suggested that the immunotherapy effect was better in the high-risk group than in the low-risk group. And we found that the high-risk group was also better than the low-risk group in terms of chemotherapy effect. In conclusion, we successfully constructed an ApoRLSig which could predict the prognosis of LUAD patients and provide a novel strategy for the antitumor treatment of LUAD patients.

Exploring the oncogenic roles of LINC00857 in pan-cancer

Although aberrant LINC00857 expression may play a key role in oncogenesis, no research has analyzed the pan-cancer oncogenic roles of LINC00857, particularly in tumor immunology. Here, we integrated data from several databases to analyze the characteristics of LINC00857 in pan-cancer. We found that LINC00857 was overexpressed and correlated with a poor prognosis in a variety of cancers. Furthermore, high-expression of LINC00857 was negatively associated with immune cell infiltration and immune checkpoint gene expression. Notably, LINC00857 expression was negatively related to microsatellite instability and tumor mutation burden in colorectal cancer, implying poor reaction to immunotherapy when LINC00857 was highly expressed. Targeting LINC00857 could dramatically impair the proliferative ability of colorectal cancer cells. After RNA-sequencing in HCT116 cells, gene set enrichment analysis showed that LINC00857 may accelerate cancer progression by inhibiting the ferroptosis pathway and promoting glycolipid metabolism in colorectal cancer. Screening by weighted gene co-expression network analysis determined PIWIL4 as a target of LINC00857, which also performed an immunosuppressive role in colorectal cancer. Based on the structure of PIWIL4, a number of small molecule drugs were screened out by virtual screening and sensitivity analysis. In summary, LINC00857 expression was closely correlated with an immunosuppressive microenvironment and may be a novel diagnostic and prognostic biomarker for diverse cancers. The LINC00857/PIWIL4 axis may be predictive biomarkers for immunotherapy and valuable molecular targets for malignant tumors.

The Emerging Role of RNA N6-Methyladenosine Modification in Pancreatic Cancer

Pancreatic cancer (PC) is one of the most common malignant cancers, ranking the seventh highest causes of cancer-related deaths globally. Recently, RNA N6-methyladenosine (m6A) is emerging as one of the most abundant RNA modifications in eukaryote cells, involved in multiple RNA processes including RNA translocation, alternative splicing, maturation, stability, and degradation. As reported, m6A was dynamically and reversibly regulated by its “writers”, “erasers”, and “readers”, Increasing evidence has revealed the vital role of m6A modification in the development of multiple types of cancers including PC. Currently, aberrant m6A modification level has been found in both PC tissues and cell lines. Moreover, abnormal expressions of m6A regulators and m6A-modified genes have been reported to contribute to the malignant development of PC. Here in this review, we will focus on the function and molecular mechanism of m6A-modulated RNAs including coding RNAs as well as non-coding RNAs. Then the m6A regulators will be summarized to reveal their potential applications in the clinical diagnosis, prognosis, and therapeutics of PC.

FAM83A antisense RNA 1 (FAM83A-AS1) silencing impairs cell proliferation and induces autophagy via MET-AMPKɑ signaling in lung adenocarcinoma

Studies demonstrate that long non-coding RNAs (lncRNAs) play vital roles in cancer progression. However, the expression pattern and molecular mechanisms of lncRNA FAM83A-AS1 in lung cancer remain largely unclear. Here, we analyzed FAM83A-AS1 expression in lung cancer tissues from three RNA-sequencing (RNA-Seq) datasets and validated these results using quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) in an independent set of lung adenocarcinoma. Cell proliferation, migration, invasion, and autophagy were analyzed after knockdown FAM83A-AS1 with siRNAs. The underlying molecular mechanisms of FAM83A-AS1 were performed by Western blot, qRT-PCR, and RNA-seq analysis. We found that FAM83A-AS1 was up-regulated in lung cancer and elevated expression was associated with poor patient survival. These results were confirmed using RT-PCR in an independent set of lung cancer. Functional study indicated that FAM83A-AS1 knockdown reduced cell proliferation, migration, invasion, and colony formation in cancer cells. FAM83A-AS1 silencing induced autophagy and cell cycle arrest at G2. Mechanistically, serval oncogenic proteins such as EGFR, MET, PI3K, and K-RAS were decreased upon FAM83A-AS1 silencing, while phosphor AMPKα and ULK1 were increased. Based on the above results, we believe that FAM83A-AS1 may have potential as a diagnosis/prognosis marker and its oncogenic role and autophagy regulation may be through MET-AMPKα signaling, which could lead to potential targeting for lung cancer therapy.

Long noncoding RNA LINC00857 promotes pancreatic cancer proliferation and metastasis by regulating the miR-130b/RHOA axis

Dysregulation of long noncoding RNAs (lncRNAs) is involved in the pathogenesis and progression of pancreatic cancer (PC). In the current study, we investigated the role and molecular mechanism of LINC00857 in PC. The expression of LINC00857 in PC was analyzed by bioinformatics analysis and qRT-PCR, and the relationship between LINC00857 expression and clinical characteristics of patients of PC was analyzed by Fisher's exact test. Gain- and loss-of-function assays were performed to determine the biological function of LINC00857 in PC. The relationship between LINC00857, miR-130b, and RHOA were determined by RNA pull-down assay, luciferase assay, and qRT-PCR. Our results demonstrated that LINC00857 expression was elevated in PC, and high expression of LINC00857 was positively associated with tumor diameter, T stage, and lymph node metastasis. LINC00857 promoted the proliferation and mobility of PC cells in vitro and in vivo. Mechanistically, LINC00857 acts as a sponge for miR-130b and decreases its expression. miR-130b exhibits tumor suppressor functions in PC, and RHOA was identified as the key target gene of miR-130b. The functions induced by LINC00857 in PC cells were dependent on the miR-130b/RHOA axis. In conclusion, the current study indicated that LINC00857 promotes PC tumorigenesis and metastasis by modulating the miR-130b/RHOA axis, implying that LINC00857 might be a new therapeutic target for PC.

YB-1 as an Oncoprotein: Functions, Regulation, Post-Translational Modifications, and Targeted Therapy

Y box binding protein 1 (YB-1) is a protein with a highly conserved cold shock domain (CSD) that also belongs to the family of DNA- and RNA-binding proteins. YB-1 is present in both the nucleus and cytoplasm and plays versatile roles in gene transcription, RNA splicing, DNA damage repair, cell cycle progression, and immunity. Cumulative evidence suggests that YB-1 promotes the progression of multiple tumor types and serves as a potential tumor biomarker and therapeutic target. This review comprehensively summarizes the emerging functions, mechanisms, and regulation of YB-1 in cancers, and further discusses targeted strategies.

MiR-379-5p Promotes Chondrocyte Proliferation via Inhibition of PI3K/Akt Pathway by Targeting YBX1 in Osteoarthritis

OBJECTIVE

We evaluated the ability of miR-379-5p to influence the proliferation of osteoarthritis chondrocytes and elucidated the regulatory mechanism of miR-379-5p in osteoarthritis.

METHODS

Real time polymerase chain reaction (RT- PCR) was used to detect the expression of miR-379-5p and YBX1 in knee articular cartilages of human. Cell proliferation, inflammatory factors, extracellular matrix (ECM) degradation-associated proteins and proteins in PI3K/Akt pathway were assessed in rat primary chondrocytes treated with interleukin (IL)-1β or/and miR-379-5p mimics or miR-379-5p inhibitor via cell counting assay kit-8 (CCK-8), enzyme-linked immunosorbent assay (ELISA), immunofluorescence and Western blotting (WB). The target of miR-379-5p predicted by TargetScan and miRwalk software was verified by luciferase reporter assay. Safranin O-fast green staining, immunohistochemistry, and WB were performed to observe the effect of miR-379-5p agomir on development of osteoarthritis in rats.

RESULTS

MiR-379-5p was down-regulated in human osteoarthritic tissues and negatively correlated with YBX1 expression. High level of miR-379-5p in chondrocytes with IL-1β stimulated increased cell viability, the expression of proliferation-related protein and extracellular matrix (ECM)-related proteins collagen II and aggrecan. However, the expression of inflammatory factors and ECM-related proteins matrix metalloproteinases (MMP-1) and MMP-13 was decreased. Luciferase reporting assay verified the targeting relationship between miR-379-5p and YBX1. This function of miR-379-5p was exerted through PI3K/Akt pathway and could be blocked by the PI3K/Akt pathway inhibitor LY294002. MiR-379-5p agomir promoted the articular chondrocytes proliferation and alleviated cartilage degradation in vivo.

CONCLUSION

Our findings reveal that miR-379-5p can promote the articular chondrocytes proliferation in osteoarthritis (OA) by interacting with YBX1 and regulating PI3K/Akt pathway. Restoring miR-379-5p might be a future therapeutic strategy for OA.

Diverse Regulation of YB-1 and YB-3 Abundance in Mammals

YB proteins are DNA/RNA binding proteins, members of the family of proteins with cold shock domain. Role of YB proteins in the life of cells, tissues, and whole organisms is extremely important. They are involved in transcription regulation, pre-mRNA splicing, mRNA translation and stability, mRNA packaging into mRNPs, including stress granules, DNA repair, and many other cellular events. Many processes, from embryonic development to aging, depend on when and how much of these proteins have been synthesized. Here we discuss regulation of the levels of YB-1 and, in part, of its homologs in the cell. Because the amount of YB-1 is immediately associated with its functioning, understanding the mechanisms of regulation of the protein amount invariably reveals the events where YB-1 is involved. Control over the YB-1 abundance may allow using this gene/protein as a therapeutic target in cancers, where an increased expression of the YBX1 gene often correlates with the disease severity and poor prognosis.

TGF-β/YB-1/Atg7 axis promotes the proliferation of hepatic progenitor cells and liver fibrogenesis

Hepatic fibrosis is characterized by excessive extracellular matrix deposition and ductular reactions, manifested as the expansion of hepatic progenitor cells (HPCs). We previously reported that the Y-box binding protein 1 (YB-1) in HPCs is involved in chronic liver injury. In this study, we constructed YB-1f/f Foxl1-Cre mice and investigated the role of YB-1 in HPC expansion in murine choline-deficient, ethionine-supplemented (CDE), and 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) models. Liver injury and fibrosis were measured using hematoxylin and eosin (HE), Masson, and Sirius Red staining. HPC proliferation was detected using EdU and immunofluorescence (IF). Autophagic flow was measured by mCherry-GFP-LC3B staining and transmission electron microscopy (TEM). YB-1 expression was measured by immunofluorescence and western blotting. CUT & Tag analysis, chromatin immunoprecipitation, and RT-PCR were performed to explore the regulation of autophagy-related protein 7 (Atg7) transcription by YB-1. Our results indicated that liver injury was accompanied by high expression of YB-1, proliferative HPCs, and activated autophagy in the CDE and DDC models. YB-1f/f Cre+/- mice displayed less liver injury and fibrosis than YB-1f/f Cre-/- mice in the CDE and DDC models. YB-1 promoted proliferation and autophagy of HPCs in vitro and in vivo. Transforming growth factor-β (TGF-β) induced YB-1 nuclear translocation and facilitated the proliferation and autophagy of HPCs. YB-1 nuclear translocation promoted the transcription of Atg7, which is essential for TGF-β/YB-1 mediated HPCs expansion in vitro and in vivo. In summary, YB-1 nuclear translocation induced by TGF-β in HPCs promotes the proliferation and autophagy of HPCs and Atg7 participates in YB-1-mediated HPC-expansion and liver fibrosis.

LINC00857 promotes the proliferation of pancreatic cancer via MET, STAT3, and CREB

BACKGROUND

Long non-coding RNA (lncRNA) LINC00857 promotes cell proliferation in various cancers and is overexpressed in pancreatic cancer (PC). However, the role of LINC00857 in PC is yet to be clarified.

METHODS

In this study, we used Gene Expression Profiling Interactive Analysis (GEPIA) to investigate transcriptional data of LINC00857 in different cancers. We determined LINC00857 expression in 4 PC cell lines, and one normal pancreatic cell line by quantitative real-time reverse transcription PCR (qRT-PCR). small interfering RNA (siRNA) was employed to specifically knockdown LINC00857 in BxPc3 and PANC1 cells. Cell proliferation was evaluated using WST-1. Western blotting analysis was used to detect the expression levels of downstream proteins of LINC00857.

RESULTS

We revealed that the knockdown of LINC00857 in PC cell lines inhibited the proliferation of the PC cells. We found that LINC00857 downregulation was followed by the downregulation of oncogenic proteins mesenchymal-epithelial transition (MET), signal transducer and activator of transcription 3 (STAT3), and cAMP response element-binding protein (CREB).

CONCLUSIONS

Our study indicated that LINC00857 regulated the expression of STAT3 and CREB via regulating the expression of MET, and consequently promoted the growth of PC cells. The results allowed us to deepen our understanding of the pathogenesis of PC and provided a potential target for the clinical treatment of PC.

Long non-coding RNA LINC01559 exerts oncogenic role via enhancing autophagy in lung adenocarcinoma

BACKGROUND

Long non-coding RNAs (lncRNAs) have been verified to play fatal role in regulating the progression of lung adenocarcinoma (LUAD). Although lncRNAs play important role in regulating the autophagy of tumor cells, the function and molecular mechanism of LINC01559 in regulating lung cancer development remain to be elucidated.

METHOD AND MATERIALS

In this study, we used bioinformatics to screen out autophagy-related lncRNAs from TCGA-LUAD repository. Then the least absolute shrinkage and selection operator (LASSO) regression was applied to establish the signature of autophagy-related lncRNAs so that clinical characteristics and survival in LUAD patients be evaluated. Finally, we selected the most significant differences lncRNA, LINC01559, to verify its function in regulating LUAD progression in vitro.

RESULTS

We found high expression of LINC01559 indicates lymph node metastasis and poor prognosis. Besides, LINC01559 promotes lung cancer cell proliferation and migration in vitro, by enhancing autophagy signal pathway via sponging hsa-miR-1343-3p.

CONCLUSION

We revealed a novel prognostic model based on autophagy-related lncRNAs, and provide a new therapeutic target and for patients with lung adenocarcinoma named LINC01559.

Non-coding RNA-mediated autophagy in cancer: A protumor or antitumor factor?

Autophagy, usually referred to as macroautophagy, is a cytoprotective behavior that helps cells, especially cancer cells, escape crises. However, the role of autophagy in cancer remains controversial. The induction of autophagy is favorable for tumor growth, as it can degrade damaged cell components accumulated during nutrient deficiency, chemotherapy, or other stresses in a timely manner. Whereas the antitumor effect of autophagy might be closely related to its crosstalk with metabolism, immunomodulation, and other pathways. Recent studies have verified that lncRNAs and circRNAs modulate autophagy in carcinogenesis, cancer cells proliferation, apoptosis, metastasis, and chemoresistance via multiple mechanisms. A comprehensive understanding of the regulatory relationships between ncRNAs and autophagy in cancer might resolve chemoresistance and also offer intervention strategies for cancer therapy. This review systematically displays the regulatory effects of lncRNAs and circRNAs on autophagy in the contexts of cancer initiation, progression, and resistance to chemo- or radiotherapy and provides a novel insight into cancer therapy.

FGF14-AS2 accelerates tumorigenesis in glioma by forming a feedback loop with miR-320a/E2F1 axis

Glioma is the most common primary tumour in the central nervous system in adults, and at present, there is no effective treatment to cure this malignancy. Long noncoding RNAs (lncRNAs) are closely related to tumour progression and have attracted increasing attention in tumour research. However, the role of lncRNA FGF14-AS2 in glioma tumorigenesis has not been determined. In the present study, we found that FGF14-AS2 expression was significantly elevated in glioma tissues and was associated with poor survival in glioma patients. Silencing FGF14-AS2 inhibited the proliferation, migration and invasion ability of glioma cells. In vivo assay showed that silencing FGF14-AS2 led to inhibition of tumour growth. In addition, FGF14-AS2 was observed to promote glioma progression via the miR-320a/E2F1 axis. Moreover, E2F1 could bind to the promoter region of FGF14-AS2, thereby enhancing FGF14-AS2 expression. In conclusion, FGF14-AS2 could accelerate tumorigenesis of glioma by forming a feedback loop with the miR-320a/E2F1 axis which suggested that FGF14-AS2 could serve as a therapeutic target for glioma.

Iridium(III)-BBIP complexes induce apoptosis via PI3K/AKT/mTOR pathway and inhibit A549 lung tumor growth in vivo

The new ligand BBIP (BBIP = 2-(7-bromo-2H-benzo[d]imidazole-4-yl)-1H-imidazo[4,5-f][1,10]phenanthroline) with its iridium(III) complexes: [Ir(ppy)2(BBIP)](PF6) (ppy = 2-phenylpyridine, Ir1), [Ir(bzq)2(BBIP)](PF6) (bzq = benzo[h]quinolone, Ir2) and [Ir(piq)2(BBIP)](PF6) (piq = 1-phenylisoquinoline, Ir3) were synthesized and characterized by elemental analysis, High Resolution Mass Spectrometer (HRMS), 1H NMR and 13C{1H} NMR. The cytotoxicity of the complexes against A549, HepG2, SGC-7901, BEL-7402, HeLa and normal LO2 was evaluated through 3-(4,5-dimethylthiazole-2-yl)-2,5-biphenyl tetrazolium bromide (MTT) method. The results show that Ir1 exhibits high cytotoxic activity against A549 cells with a low IC50 value of 4.9 ± 0.5 μM. A series of biological activities such as cell cycle arrest, endoplasmic reticulum localization assay, apoptosis, western blotting, cellular uptake determination and in vivo antitumor activity were investigated. The assays implied that the complexes inhibit cancer cell migration through blocking mitotic progress. Cell cycle distribution stated that the complexes depress cell growth at G0/G1 phase. Additionally, the complexes acted on the endoplasmic reticulum and induce apoptosis through endoplasmic reticulum stress pathway. Especially, the western blotting showed that the complexes activated Bcl-2 (B-cell lymphoma-2) family and decreased PI3K (phosphoinositide-3 kinase) and AKT (protein kinase B), up-regulated the expression of mTOR (mammalian target of rapamycin) and p-mTOR (phosphorylated mammalian target of rapamycin). Therefore, the complexes induce apoptosis through activating PI3K-AKT-mTOR pathway. Antitumor in vivo demonstrated that Ir1 can effectively prevent the tumor growth with an inhibitory rate of 48.89%.

CSE1L silencing impairs tumor progression via MET/STAT3/PD-L1 signaling in lung cancer

CSE1L is involved in the cancer progression of several types of cancer. Its expression status, potential oncogenic role and underlying mechanism in lung cancer, however, are unclear. Here, we investigated CSE1L expression in primary lung adenocarcinoma based on multiple datasets and then investigated its oncologic role in lung cancer. We also examined the potential molecular mechanisms of CSE1L in cancer progression. CSE1L levels were increased in cancer as compared to normal lung tissues. CSE1L expression was higher in poorly-differentiated late stage and lymph node positive metastatic tumors. Higher CSE1L level was correlated with worse patient outcome. Knockdown of CSE1L using siRNAs impaired cell proliferation, invasion, migration and induced cell apoptosis. Mechanistically, MET, STAT3 and PD-L1 proteins were decreased upon CSE1L silencing. These results suggest that CSE1L may affect tumor progression through MET/STAT3/PD-L1 signaling. CSE1L may have potential as a biomarker and therapeutic target for lung cancer.

Potential therapeutic strategies for targeting Y-box-binding protein 1 in cancers

As one of the most conservative proteins in evolution, Y-box-binding protein 1 (YB-1) has long been considered as a potential cancer target. YB-1 is usually poorly expressed in normal cells and exerts cellular physiological functions such as DNA repair, pre-mRNA splicing and mRNA stabilizing. In cancer cells, the expression of YB-1 is up-regulated and undergoes nuclear translocation and contributes to tumorigenesis, angiogenesis, tumor proliferation, invasion, migration and chemotherapy drug resistance. During the past decades, a variety of pharmacological tools such as siRNA, shRNA, microRNA, circular RNA, lncRNA and various compounds have been developed to target YB-1 for cancer therapy. In this review, we describe the physiological characteristics of YB-1 in detail, highlight the role of YB-1 in tumors and summarize the current therapeutic methods for targeting YB-1 in cancer.