Role of long non-coding RNA in drug resistance in non-small cell lung cancer

A Novel Competing Endogenous RNA Network Reveals Potential Mechanisms and Biomarkers of Chemoresistance in Lung Adenocarcinoma

Platinum resistance is a common cause of chemotherapy failure in lung adenocarcinoma (LUAD). Competing endogenous RNAs (ceRNAs), which function by competitively binding to miRNAs, can influence drug response. However, the regulatory mechanisms of ceRNAs underlying chemoresistance in LUAD remain largely unknown. Here, we proposed an integrated pipeline combining limma algorithm, miRNA binding prediction algorithm, expression correlation model and experimental support to identify functional lncRNA-miRNA-mRNA competing triplets associated with resistance, which showed variable competing patterns between resistant and sensitive cells. We found that a minority of altered ceRNAs overlapped in multiple types of cisplatin-resistant LUAD cell lines and were involved in biological processes known to mediate cancer drug response. We identified them as core resistance factors, forming a novel lncRNA-mediated resistance-related ceRNA network, which indicated a potential mechanism. Single-cell analysis revealed that these resistance-related ceRNAs regulated the functional states of LUAD cells, and survival analysis showed that they contributed to the prognosis of LUAD patients. The lncRNA regulators H19 and MIR193BHG were found to correlate with cisplatin activity in LUAD cell lines, and dysregulation of their expression triggered disorders of cisplatin response-related functions through multiple ceRNA regulatory axes in this network, suggesting them as potential resistance biomarkers and therapeutic targets. In summary, the integrated pipeline and the resulting data serve as a valuable resource for understanding the ceRNA mechanisms of chemoresistance and improving chemotherapy response.

Mechanism of the KIAA1429/KLF1/PD-L1 Axis in Regulating Immune Escape in Non-small Cell Lung Cancer

Non-small cell lung cancer (NSCLC), accounting for approximately 80% of lung cancer cases, remains the leading cause of cancer-related mortality. Immune evasion is a critical challenge in NSCLC, contributing to poor treatment outcomes. This study investigates the role of KIAA1429 in immune evasion, aiming to identify novel therapeutic targets and provide a theoretical basis for NSCLC treatment. NSCLC cell lines were cultured to assess the expression of KIAA1429, KLF transcription factor (KLF1), and programmed cell death ligand 1 (PD-L1). Co-culture experiments were conducted with peripheral blood mononuclear cells (PBMCs) to evaluate cytotoxicity, CD8+T cell proportions, and levels of interferon-gamma (IFN-γ)/interleukin (IL)-10/IL-2. Additionally, N6-methyladenosine (m6A) modification in NSCLC cells, m6A enrichment on KLF1, and KLF1 mRNA stability were analyzed. Results showed increased expression of KIAA1429 and KLF1 in NSCLC cells. Knockdown of KIAA1429 inhibited NSCLC cell proliferation, enhanced PBMC cytotoxicity and CD8+T cell activation, increased IFN-γ and IL-2 levels, and decreased IL-10 levels. Mechanistically, KIAA1429 stabilized KLF1 mRNA level through m6A modification, promoting both KLF1 and PD-L1 expression. Overexpression of KLF1 or PD-L1 reversed the immune-modulating effects of KIAA1429 knockdown. In conclusion, KIAA1429 facilitates immune evasion in NSCLC by stabilizing KLF1 mRNA and upregulating PD-L1 expression.

Long non-coding RNA (lncRNA) PVT1 in drug resistance of cancers: Focus on pathological mechanisms

According to estimates, cancer will be the leading cause of death globally in 2022, accounting for 9.6 million deaths. At present, the three main therapeutic modalities utilized to treat cancer are radiation therapy, chemotherapy, and surgery. However, during treatment, tumor cells resistant to chemotherapy may arise. Drug resistance remains a major oppose since it often leads to therapeutic failure. Furthermore, the term "acquired drug resistance" describes the situation where tumor cells already display drug resistance before undergoing chemotherapy. However, little is still known about the basic mechanisms underlying chemotherapy-induced drug resistance. The development of new technologies and bioinformatics has led to the discovery of additional genes associated with drug resistance. Long noncoding RNA plasmacytoma variant translocation 1 (PVT1) has been linked to an increased risk of cancer, according to a growing body of research. Apart from biological functions associated with cell division, development, pluripotency, and cell cycle, lncRNA PVT1 contributes significantly to the regulation of various aspects of genome function, such as transcription, splicing, and epigenetics. The article will address the mechanism by which lncRNA PVT1 influences drug resistance in cancer cells.

SETD1A-mediated Methylation of H3K4me3 Inhibits Ferroptosis in Non-small Cell Lung Cancer by Regulating the WTAPP1/WTAP Axis

INTRODUCTION

SETD1A is upregulated in non-small cell lung cancer (NSCLC) tissues. This study investigated the molecular mechanism of the SETD1A/WTAPP1/WTAP axis in NSCLC.

METHODS

Ferroptosis is a unique cell death mode driven by iron-reliant phospholipid peroxidation, which is regulated by multiple cellular metabolic pathways, including REDOX homeostasis, iron metabolism, mitochondrial activity and metabolism of amino acids, lipids and sugars. Thus, the levels of ferroptosis markers (MDA, SOD, GSH) were measured in vitro, and NSCLC cell behaviors were assessed. SETD1A-mediated H3K4me3 methylation was analyzed. SETD1A-exerted effects on ferroptosis and tumor growth in vivo were verified in nude mouse models.

RESULTS

SETD1A was highly expressed in NSCLC cells. Silencing SETD1A suppressed NSCLC cell proliferation and migration, inhibited MDA, and enhanced GPX4, SOD, and GSH levels. SETD1A elevated WTAP expression through WTAPP1 upregulation by mediating H3K4me3 methylation in the WTAPP1 promoter region. WTAPP1 overexpression partly averted the promotional effect of silencing SETD1A on NSCLC cell ferroptosis. WTAP interference abrogated the inhibitory effects of WTAPP1 on NSCLC cell ferroptosis. Silencing SETD1A facilitated ferroptosis and accelerated tumor growth in nude mice through the WTAPP1/WTAP axis.

CONCLUSION

SETD1A amplified WTAP expression through WTAPP1 upregulation by mediating H3K4me3 modification in the WTAPP1 promoter region, thus promoting NSCLC cell proliferation and migration and inhibiting ferroptosis.

Recent progress and the emerging role of lncRNAs in cancer drug resistance; focusing on signaling pathways

It is becoming more and more apparent that many of the genetic alterations associated with cancer are located in areas that do not encode proteins. lncRNAs are a class of RNAs that do not code for proteins but play a crucial role in maintaining cell function and regulating various cellular processes. By doing this, they have recently introduced what may be a brand-new and essential layer of biological control. These have more than 200 nucleotides and are linked to several diseases; as a result, they have become potential tools for therapeutic intervention. Emerging technologies suggest the presence of mutations on genomic loci that give rise to lncRNAs rather than proteins in a disease as complex as cancer. These lncRNAs play essential parts in gene regulation, which impacts several cellular homeostasis processes, including proliferation, survival, migration, and genomic stability. The leading cause of death in the world today is cancer. Delays in diagnosis and a lack of standard and efficient treatments are the leading causes of the high death rate. Clinically, surgery is frequently used successfully to remove cancers that have not spread, but it is less successful in treating metastatic cancer, which has a drastically lower chance of survival. Chemotherapeutic drugs are a typical therapy to treat the cancer that has spread to other organs. Drug resistance to chemotherapy, however, presents a significant challenge to achieving positive outcomes and is frequently the cause of treatment failure. A substantial barrier to progress in medical oncology is cancer drug resistance. Resistance can develop clinically either before or after cancer treatment. According to this study, lncRNAs influence drug resistance through several different methods. LncRNAs often impact drug resistance by controlling the expression of a few intermediary regulatory variables rather than by directly affecting drug resistance. Additionally, lncRNAs have a variety of roles in cancer medication resistance. Most lncRNAs induce drug resistance when overexpressed; however, other lncRNAs have inhibitory effects. This study provides an overview of the current understanding of lncRNAs, relevance to cancer, and potential therapeutic applications.

PTCSC3, XIST, GAS5, UCA1, and HIFAL: Five lncRNAs Emerging as Potential Prognostic Players in Egyptian Adult Acute Myeloid Leukemia (AML) Patients

BACKGROUND AND AIMS

So far, long noncoding RNAs (lncRNAs) signatures in acute myeloid leukemia (AML) are poorly understood. The present study aims to explore the prognostic significance of eleven cancer-related lncRNAs in bone marrow (BM) samples from adult Egyptian AML patients.

MATERIALS AND METHODS

In this study, we analyzed eleven lncRNAs using the qRT-PCR assay in the bone marrow (BM) of 79 de novo AML adult patients before receiving any therapy.

RESULTS

Five lncRNAs out of 11 were aberrantly expressed, and two lncRNAs influenced significantly the patient's overall survival (OS). LncRNA-XIST was favorable when overexpressed (in univariate and multivariate analysis, P-value = .001). LncRNA-GAS5 adversely affected the OS (only in multivariate analysis P-value = .02). Two other lncRNAs (UCA1 and HIFAL) impacted complete remission induction (CR) significantly in univariate analysis (P-value = .046 for both). Furthermore, lncRNA-UCA1 affected CR significantly in multivariate COX regression analysis (P-value = .004). The 4 previously mentioned lncRNAs were among the 9 downregulated lncRNAs. Instead, the only 2 upregulated lncRNAs (SNHG15, MALAT1) did not significantly influence neither CR induction nor OS. LncRNA-PTCSC3, a fifth lncRNA, emerged as the only one that could predict relapse occurrence in an upfront original BM sample.

CONCLUSION

Two lncRNAs out of eleven (lncRNA-XIST and GAS5) impacted OS, and two other lncRNAs (UCA1 and HIFAL) affected CR in adult de novo AML patients. LncRNA-PTCSC3 predict relapse, however, further validation is still required.

Long noncoding RNA LINC00482 silencing sensitizes non-small cell lung cancer cells to cisplatin by downregulating CLASRP via E2F1

Long noncoding RNA LINC00482 (LINC00482) is dysregulated in non-small cell lung cancer cells (NSCLC). Herein, this research examined the actions and specific mechanisms of LINC00482 in cisplatin (DDP) resistance in NSCLC. LINC00482 expression was assessed using RT-qPCR in clinical NSCLC tissues and cell lines. Knockdown and ectopic expression assays were conducted in A549 and HCC44 cells, followed by determination of cell proliferation with CCK-8 and clone formation assays, apoptosis with flow cytometry, and DDP sensitivity. The association between LINC00482, E2F1, and CLASRP was evaluated with dual-luciferase reporter, ChIP, and RIP assays. The role of LINC00482 in NSCLC was confirmed in nude mice. NSCLC tissues and cells had upregulated LINC00482 expression. LINC00482 was mainly localized in the cell nucleus, and LINC00482 recruited E2F1 to enhance CLASRP expression in NSCLC cells. LINC00482 knockdown enhanced the DDP sensitivity and apoptosis of NSCLC cells while reducing cell proliferation, which was negated by overexpressing CLASRP. LINC00482 knockdown restricted tumor growth and enhanced DDP sensitivity in NSCLC in vivo. LINC00482 silencing downregulated CLASRP through E2F1 to facilitate the sensitivity to DDP in NSCLC.

LncRNA polymorphisms and lung cancer risk

Lung cancer (LC) imposes a significant burden, and is associated with high mortality and morbidity among malignant tumors. Aberrant expression of particular lncRNAs is closely linked to LC. LncRNA polymorphisms cause abnormal expression levels and/or structural dysfunction. They can affect the progression of cancer, survival, response to chemotherapy and recurrence rates in cancer patients. The present article provides a comprehensive overview of the effect of lncRNA genetic polymorphisms on LC. It is proposed that lncRNA-related variants can be used to predict cancer risk and therapeutic outcomes. More large-scale trials on diverse ethnic groups are required to validate the results, thus personalizing LC therapy based on lncRNA genotypes.

Non-coding RNA-based therapeutics in cancer therapy: An emphasis on Wnt/β-catenin control

Non-coding RNA transcripts are RNA molecules that have mainly regulatory functions and they do not encode proteins. microRNAs (miRNAs), lncRNAs and circRNAs are major types of this family and these epigenetic factors participate in disease pathogenesis, especially cancer that their abnormal expression may lead to cancer progression. miRNAs and lncRNAs possess a linear structure, whereas circRNAs possess ring structures and high stability. Wnt/β-catenin is an important factor in cancer with oncogenic function and it can increase growth, invasion and therapy resistance in tumors. Wnt upregulation occurs upon transfer of β-catenin to nucleus. Interaction of ncRNAs with Wnt/β-catenin signaling can determine tumorigenesis. Wnt upregulation is observed in cancers and miRNAs are able to bind to 3'-UTR of Wnt to reduce its level. LncRNAs can directly/indirectly regulate Wnt and in indirect manner, lncRNAs sponge miRNAs. CircRNAs are new emerging regulators of Wnt and by its stimulation, they increase tumor progression. CircRNA/miRNA axis can affect Wnt and carcinogenesis. Overall, interaction of ncRNAs with Wnt can determine proliferation rate, migration ability and therapy response of cancers. Furthermore, ncRNA/Wnt/β-catenin axis can be utilized as biomarker in cancer and for prognostic applications in patients.

Targeting immune cell types of tumor microenvironment to overcome resistance to PD-1/PD-L1 blockade in lung cancer

Lung cancer is the common malignant tumor with the highest mortality rate. Lung cancer patients have achieved benefits from immunotherapy, including immune checkpoint inhibitors (ICIs) therapy. Unfortunately, cancer patients acquire adaptive immune resistance, leading to poor prognosis. Tumor microenvironment (TME) has been demonstrated to play a critical role in participating in acquired adaptive immune resistance. TME is associated with molecular heterogeneity of immunotherapy efficacy in lung cancer. In this article, we discuss how immune cell types of TME are correlated with immunotherapy in lung cancer. Moreover, we describe the efficacy of immunotherapy in driven gene mutations in lung cancer, including KRAS, TP53, EGFR, ALK, ROS1, KEAP1, ZFHX3, PTCH1, PAK7, UBE3A, TNF-α, NOTCH, LRP1B, FBXW7, and STK11. We also emphasize that modulation of immune cell types of TME could be a promising strategy for improving adaptive immune resistance in lung cancer.

The crucial roles of long noncoding RNA SNHGs in lung cancer

Lung cancer is one of the most common malignant tumors with growing morbidity and mortality worldwide. Several treatments are used to manage lung cancer, including surgery, radiotherapy and chemotherapy, as well as molecular-targeted therapy. However, the current measures are still far from satisfactory. Therefore, the current research should focus on exploring the molecular mechanism and then finding an effective treatment. Interestingly, we and others have embarked on a line of investigations focused on the mechanism of lung cancer. Specifically, lncRNA small nucleolar RNA host gene has been shown to be associated with biological characteristics and therapeutic resistance of lung cancer. In addition, small nucleolar RNA host genes may be used as diagnostic biomarker in the future. Herein, we will provide a brief review demonstrating the importance of small nucleolar RNA host genes in lung cancer, especially non-small cell lung cancer. Although lncRNA has shown a crucial role in tumor-related research, a large number of studies are needed to validate its clinical application in the future.

Mechanism of lncRNA H19 in Regulating Pulmonary Injury in Hyperoxia-Induced Bronchopulmonary Dysplasia Newborn Mice

OBJECTIVE

Bronchopulmonary dysplasia (BPD) is a pulmonary injury related to inflammation and is a major cause of premature infant death. Long noncoding RNAs (lncRNAs) are important regulators in pulmonary injury and inflammation. We investigated the molecular mechanism of lncRNA H19 in pulmonary injury and inflammation in hyperoxia (Hyp)-induced BPD mice.

STUDY DESIGN

The BPD newborn mouse model was established and intervened with H19 to evaluate the pathologic conditions and radial alveolar count (RAC) in lung tissues of mice in the room air (RA) and Hyp group on the 4th, 7th, and 14th days after birth. The levels of BPD-related biomarkers vascular endothelial growth factor (VEGF), transforming growth factor β1 (TGF-β1), and surfactant protein C (SPC) in lung tissues were detected on the 14th day after birth. The expression of and relationships among H19 and miR-17, miR-17, and STAT3 were detected and verified. Levels of interleukin (IL)-6, IL-1β, p-STAT3, and STAT3 levels in mouse lung tissues were detected on the 14th day after birth.

RESULTS

Hyp-induced mice showed increased alveolar diameter, septum, and hyperemia and inflammatory cell infiltration, upregulated H19, decreased overall number and significantly reduced RAC on the 7th and 14th days after birth, which were reversed in the si-H19-treated mice. VEGF was upregulated and TGF-β1 and SPC was decreased in si-H19-treated mice. Moreover, H19 competitively bound to miR-17 to upregulate STAT3. IL-6 and IL-1β expressions and p-STAT3 and STAT3 levels were downregulated after inhibition of H19.

CONCLUSION

Downregulated lncRNA H19 relieved pulmonary injury via targeting miR-17 to downregulate STAT3 and reduced inflammatory response caused by p-STAT3 in BPD newborn mice.

KEY POINTS

· lncRNA H19 was highly expressed in Hyp-induced BPD newborn mice.. · si-H19 relieved pulmonary injury in Hyp-induced BPD newborn mice.. · si-H19 upregulated miR-17 and downregulated STAT3 expression..

NLR family CARD domain containing 5 promotes hypoxia-induced cancer progress and carboplatin resistance by activating PI3K/AKT via carcinoembryonic antigen related cell adhesion molecule 1 in non-small cell lung cancer

It is well known that non-small cell lung cancer (NSCLC) is a malignant tumor with high incidence in the world. We aimed to clarify a possible target and identify its precise molecular biological mechanism in NSCLC. NLR family CARD domain containing 5 (NLRC5) is widely expressed in tissues and exerts a vital role in anti-tumor immunity. We determined NLRC5 expression by RT-qPCR and western blot assay. The role of NLRC5 in the development of NSCLC was assessed by a loss-of-function assay. CCK-8, Annexin-V-FITC/PI Apoptosis Detection Kit, Transwell, and wound healing assays were used to determine the cell functions. Drug resistance-related proteins were analyzed by western blot assay. Furthermore, the modulation of NLRC5 on carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) expression and subsequent PI3K/AKT signaling was assessed. In this study, a hyper-expression of NLRC5 was found in NSCLC tissues and cell lines. Knockdown of NLRC5 suppressed cell viability, invasion, and migration, and furthermore promoted cell apoptosis in NSCLC cells. Moreover, under normoxia or hypoxia treatment, the upregulation of NLRC5 was related to carboplatin resistance. NLRC5 silencing increased carboplatin-resistant cell chemosensitivity, as evidenced by the increase in the cell inhibition rate and decrease in drug resistance-related protein expression. Mechanistically, NLRC5 knockdown inhibited the expression of CEACAM1 and subsequently blocked the PI3K/AKT signaling pathway. In conclusion, NLRC5 promotes the malignant biological behaviors of NSCLC cells by activating the PI3K/AKT signaling pathway via the regulation of CEACAM1 expression under normoxia and hypoxia.

Functions of non-coding RNAs in regulating cancer drug targets

With the development of precision medicine, the efficiency of tumor treatment has been significantly improved. More attention has been paid to targeted therapy and immunotherapy as the key to precision treatment of cancer. Targeting epidermal growth factor receptor (EGFR) has become one of the most important targeted treatments for various cancers. Comparing with traditional chemotherapy drugs, targeting EGFR is highly selective in killing tumor cells with better safety, tolerability and less side effect. In addition, tumor immunotherapy has become the fourth largest tumor therapy after surgery, radiotherapy and chemotherapy, especially immune checkpoint inhibitors. However, these treatments still produce a certain degree of drug resistance. Non-coding RNAs (ncRNAs) were found to play a key role in carcinogenesis, treatment and regulation of the efficacy of anticancer drugs in the past few years. Therefore, in this review, we aim to summarize the targeted treatment of cancers and the functions of ncRNAs in cancer treatment.

Long non-coding RNA small nucleolar RNA host genes: functions and mechanisms in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors of the digestive system, with a high degree of malignancy. Although treatment methods are constantly improving, the mortality of patients is still very high, and the small nucleolar RNA host gene (SNHG) plays an important role in the occurrence and development of cancer. It can activate downstream signaling molecules by acting on microRNA and microRNA target genes, promote the proliferation, invasion, and migration of HCC cells, and provide a new molecular target for the treatment of HCC. At present, the molecular mechanisms of HCC remain unclear. In this study, the mechanism and signaling pathway of SNHG in HCC are reviewed, which provides a theoretical basis for the clinical treatment of HCC.

Long noncoding RNASEH1-AS1 exacerbates the progression of non-small cell lung cancer by acting as a ceRNA to regulate microRNA-516a-5p/FOXK1 and thereby activating the Wnt/β-catenin signaling pathway

BACKGROUND

Till now, no study has focused on the functions of RNASEH1 antisense RNA 1 (RNASEH1-AS1) in non-small cell lung cancer (NSCLC). Accordingly, we measured the expression of RNASEH1-AS1 in NSCLC and characterized its functions in detail. Finally, our research elucidated the mechanisms that occurred downstream of RNASEH1-AS1.

METHODS

RNASEH1-AS1 expression was examined utilizing TCGA database and qRT-PCR. Functional experiments were conducted to study the tumor-associated functions of RNASEH1-AS1. The targeting relationship among RNASEH1-AS1, microRNA-516a-5p (miR-516a-5p), and forkhead box K1 (FOXK1) was revealed utilizing RNA immunoprecipitation and luciferase reporter assays.

RESULTS

Utilizing TCGA database and our own cohort, we found a significantly increased level of RNASEH1-AS1 in NSCLC. The high level of RNASEH1-AS1 was markedly related with poor clinical outcomes. Knockdown of RNASEH1-AS1 expression inhibited NSCLC cell growth, metastatic capacities, and epithelial-mesenchymal transition and promoted the apoptosis in vitro, whereas RNASEH1-AS1 overexpression exerted the opposite effects. Additionally, knocking down RNASEH1-AS1 expression suppressed tumor growth in vivo. RNASEH1-AS1 was confirmed to act as a miR-516a-5p sponge, consequently upregulating FOXK1 expression in NSCLC cells. As revealed by the subsequent rescue experiments, the miR-516a-5p/FOXK1 axis served as a downstream effector of RNASEH1-AS1. In addition, by controlling the miR-516a-5p/FOXK1 axis, RNASEH1-AS1 was capable of activating the Wnt/β-catenin pathway.

CONCLUSION

RNASEH1-AS1 exacerbated the oncogenicity of NSCLC by affecting the miR-516a-5p/FOXK1 axis and consequently promoting the activation of Wnt/β-catenin pathway. Our newly identified RNASEH1-AS1/miR-516a-5p/FOXK1/Wnt/β-catenin network may offer an interesting foundation for NSCLC treatment in the clinic.

Long non‑coding RNA LINC01748 exerts carcinogenic effects in non‑small cell lung cancer cell lines by regulating the microRNA‑520a‑5p/HMGA1 axis

The important functions of long non‑coding RNAs in the malignancy of non‑small cell lung cancer (NSCLC) has been increasingly highlighted. However, whether LINC01748 functions in a crucial regulatory role still requires further research. The aim of the present study was to investigate the biological roles of LINC01748 in NSCLC. Furthermore, different experiments were utilized to investigate the mechanism of action of LINC01748 in 2 NSCLC cell lines. Reverse transcription‑quantitative PCR was used to measure mRNA expression levels. Cell Counting Kit‑8 assay, flow cytometry analysis and Transwell and Matrigel assays were also used to analyze, cell viability, apoptosis, and migration and invasion, respectively. A tumor xenograft model was used for in vivo experiments. RNA immunoprecipitation experiments, luciferase reporter assays and rescue experiments were used to investigate the mechanisms involved. Data from The Cancer Genome Atlas dataset and patients recruited into the present study showed that LINC01748 was overexpressed in NSCLC. Patients with high LINC01748 mRNA expression level had shorter overall survival rate compared with that in patients with low LINC01748 mRNA expression level. Then, knockdown of LINC01748 mRNA expression level reduced cell proliferation, migration and invasion, but increased cell apoptosis in vitro. Knockdown of LINC01748 also reduced tumor growth in vivo. Mechanistically, LINC01748 could act as a competing endogenous (ce)RNA to sponge microRNA(miR)‑520a‑5p, to increase the expression level of the target gene, high mobility group AT‑hook 1 (HMGA1) in the NSCLC cell lines. Furthermore, rescue experiments illustrated that the functions exerted by LINC01748 knockdown were negated by miR‑520a‑5p inhibition or HMGA1 overexpression. In summary, LINC01748 acted as a ceRNA by sponging miR‑520a‑5p, leading to HMGA1 overexpression, thus increasing the aggressiveness of the NSCLC cells. Accordingly, targeting the LINC01748/miR‑520a‑5p/HMGA1 pathway may benefit NSCLC therapy.

Long Noncoding RNA LAMTOR5-AS1 Interference Affects MicroRNA-506-3p/E2F6-Mediated Behavior of Non-Small Cell Lung Cancer Cells

Long noncoding RNA LAMTOR5 antisense RNA 1 (LAMTOR5-AS1) has been certified as a risk predictor and diagnostic biomarker of prostate cancer. However, the expression and exact roles of LAMTOR5-AS1 in non-small cell lung cancer (NSCLC) remain unclear. Thus, we measured LAMTOR5-AS1 expression in NSCLC and gauged its clinical value. The detailed roles and downstream working mechanism of LAMTOR5-AS1 in NSCLC were comprehensively unraveled. qRT-PCR was applied to measure gene expression. Functionally, utilizing small interfering RNA, LAMTOR5-AS1 was ablated, and the functional alterations were addressed by means of different experiments. The targeting activities between LAMTOR5-AS1 and microRNA-506-3p (miR-506-3p) and between miR-506-3p and E2F transcription factor 6 (E2F6) were confirmed by RNA immunoprecipitation and luciferase reporter assays. LAMTOR5-AS1 overexpression in NSCLC was verified in TCGA datasets and our own cohort and manifested an evident relationship with poor prognosis. Interference with LAMTOR5-AS1 led to repression of the proliferation, cloning, and metastasis abilities of NSCLC cells in vitro. We further confirmed an obvious increase in LAMTOR5-AS1-silenced NSCLC cell apoptosis. Furthermore, the absence of LAMTOR5-AS1 restricted tumor growth in vivo. Mechanistically, LAMTOR5-AS1 sponged miR-506-3p in NSCLC cells. Furthermore, E2F6, a downstream target of miR-506-3p, was under the control of LAMTOR5-AS1, which was realized by decoying miR-506-3p. Rescue experiments showed that miR-506-3p suppression or E2F6 reintroduction was capable of remitting LAMTOR5-AS1 deficiency-triggered anticarcinogenic actions in NSCLC. Our study confirmed the exact roles of LAMTOR5-AS1 for the first time and revealed that LAMTOR5-AS1 knockdown disrupts the malignancy of NSCLC by targeting the miR-506-3p/E2F6 axis. Targeting the LAMTOR5-AS1/miR-506-3p/E2F6 pathway may be instrumental for managing patients with NSCLC.

The Interaction Between Long Non-Coding RNAs and Cancer-Associated Fibroblasts in Lung Cancer

Despite great advances in research and treatment, lung cancer is still one of the most leading causes of cancer-related deaths worldwide. Evidence is mounting that dynamic communication network in the tumor microenvironment (TME) play an integral role in tumor initiation and development. Cancer-associated fibroblasts (CAFs), which promote tumor growth and metastasis, are the most important stroma component in the tumor microenvironment. Consequently, in-depth identification of relevant molecular mechanisms and biomarkers related to CAFs will increase understanding of tumor development process, which is of great significance for precise treatment of lung cancer. With the development of sequencing technologies such as microarray and next-generation sequencing, lncRNAs without protein-coding ability have been found to act as communicators between tumor cells and CAFs. LncRNAs participate in the activation of normal fibroblasts (NFs) to CAFs. Moreover, activated CAFs can influence the gene expression and secretion characteristics of cells through lncRNAs, enhancing the malignant biological process in tumor cells. In addition, lncRNA-loaded exosomes are considered to be another important form of crosstalk between tumor cells and CAFs. In this review, we focus on the interaction between tumor cells and CAFs mediated by lncRNAs in the lung cancer microenvironment, and discuss the analysis of biological function and molecular mechanism. Furthermore, it contributes to paving a novel direction for the clinical treatment of lung cancer.

lncRNA GAS5 Sensitizes Breast Cancer Cells to Ionizing Radiation by Inhibiting DNA Repair

Radioresistance of breast cancer is a major reason for therapeutic failure and limits further increases in the dose of radiation due to severe adverse effects. Recently, long noncoding RNAs (lncRNAs) have been shown to regulate cancer proliferation, chemoresistance, and radioresistance. Among these lncRNAs, lncRNA GAS5 expression was shown to be downregulated in breast cancer and related to trastuzumab resistance. However, its role in the radiation response is unclear. In this study, we demonstrated that lncRNA GAS5 expression was reduced in irradiated cells and that overexpression of GAS5 reduced cell viability and promoted cell apoptosis after irradiation. Moreover, overexpression of GAS5 resulted in increased G2/M arrest and unrepaired DNA damage, indicating a radiosensitizing role of GAS5 in breast cancer cells. Finally, we found that a GAS5-interacting miRNA, miR-21, reversed the radiosensitizing effects of GAS5 by inhibiting the apoptotic pathway. In conclusion, we found that lncRNA GAS5 sensitized breast cancer cells to ionizing radiation by inhibiting DNA repair and suppressing miR-21, identifying novel targets for breast cancer radiosensitization.

LncRNA SNHG12 in extracellular vesicles derived from carcinoma-associated fibroblasts promotes cisplatin resistance in non-small cell lung cancer cells

Non-small-cell lung cancer (NSCLC) is defined as the most universally diagnosed class of lung cancer. Cisplatin (DDP) is an effective drug for NSCLC, but tumors are prone to drug resistance. The current study set out to evaluate the regulatory effect of long non-coding RNA (lncRNA) small nucleolar RNA host gene 12 (SNHG12) in extracellular vesicles (EVs) derived from carcinoma-associated fibroblasts (CAFs) on DDP resistance in NSCLC cells. Firstly, NSCLC cells were treated with EVs, followed by detection of cell activity, IC50 values, cell proliferation and apoptosis, and Cy3-SNHG12. We observed that CAFs-EVs promoted IC50 values and cell proliferation and inhibited apoptosis. In addition, we learned that lncRNA SNHG12 carried by CAFs-EVs into NSCLC facilitated DDP resistance of NSCLC cells. Furthermore, ELAV like RNA binding protein 1 (HuR/ELAVL1) binding to lncRNA SNHG12 and X-linked inhibitor of apoptosis (XIAP) was verified and RNA stability of XIAP was also verified CAFs-EVs promoted RNA stability and transcription of XIAP, while silencing HuR could partially-reverse this promoting effect. Further joint experimentation showed that silencing XIAP partially inhibited DDP resistance in NSCLC cells. Additionally, the tumor growth and the positive rate of Ki67 and HuR were detected, which showed that CAFs-oe-EVs promoted the tumor and the positive rate of Ki67, as well as the levels of lncRNA SNHG12, HuR, and XIAP in vivo. Collectively, our findings indicated that lncRNA SNHG12 carried by CAFs-EVs into NSCLC cells promoted RNA stability and XIAP transcription by binding to HuR, thus augmenting DDP resistance in NSCLC cells.

LncRNA-ENST00000556926 regulates the proliferation, apoptosis and mRNA transcriptome of malignant-transformed BEAS-2B cells induced by coal tar pitch

As a byproduct of coal tar distillation, coal tar pitch (CTP) has been proven to be carcinogenic to human. However, the mechanisms of lung cancer induced by CTP are still unclear. It has been shown that long non-coding RNAs (LncRNAs) play an important role in the development of human cancers. This study aims to investigate the effect of LncRNA-ENST00000556926 on malignant-transformed human bronchial epithelial (BAES-2B) cells induced by coal tar pitch extracts (CTPE). In this study, BEAS-2B cells were treated with 2.4 μg/ml of CTPE for 72 h and then passaged; and the cells were treated 4 times in the same procedure, then passaged until passage 30 (CTPE30). Cell counting kit-8 (CCK-8) assay was used to detect cell viability, then cell cycle and apoptosis were analyzed by flow cytometry, and transcriptome sequencing analysis was used to detect differentially expressed mRNAs after interference of ENST00000556926. The results indicated that the expression of ENST00000556926 in CTPE30 group was significantly higher compared with control group. Furthermore, after interfering the expression of ENST00000556926, cell viability was inhibited, and cell cycle was arrested while apoptosis of malignant-transformed BEAS-2B cells was promoted. Moreover, a total of 159 differentially expressed mRNAs were screened out after interference of ENST00000556926, including 62 up-regulated mRNAs and 97 down-regulated mRNAs. In addition, knockdown of ENST00000556926 decreased the expression of thioredoxin domain containing 5 (TXNDC5) and FOXD1. In conclusion, LncRNA-ENST00000556926 could regulate the proliferation, apoptosis and mRNA transcriptome of malignant-transformed BEAS-2B cells induced by CTP, which may provide a novel treatment strategy for lung cancer.

LncRNA GAS5 expression in non-small cell lung cancer tissues and its correlation with Ki67 and EGFR

OBJECTIVE

This research explored and analyzed LncRNA GAS5 expression in non-small cell lung cancer (NSCLC) tissues and its correlation with Ki67 and EGFR.

METHODS

A total of 130 samples of paraffin-embedded NSCLC tissues and para-cancerous normal tissues that were collected in the Department of Pathology from January 2014 to April 2016 were selected. The relative expression of LncRNA GAS5 and Ki67/EGFR in both NSCLC tissues and para-cancerous normal tissues were detected via RT-PCR and immunohistochemistry respectively. Subsequently, we analyzed the relative expression of LncRNA GAS5, the expression of Ki67/EGFR and its correlation with clinicopathological features and prognosis of patients, and studied the correlation between LncRNA GAS5 and Ki67/EGFR.

RESULTS

The relative expression of LncRNA GAS5 in NSCLC tissues was substantially less than that of the para-cancerous normal tissues (P<0.05). The positive expression rate of Ki67/EGFR in NSCLC tissues remarkably exceeded that in para-cancerous normal tissues (P<0.05). The relative expression of LncRNA GAS5 was correlated with the degree of tumor differentiation, TNM staging and lymph node metastasis (P<0.05). The positive expression rate of Ki67 and EGFR in NSCLC tissues was related to TNM stage and metastasis of lymph node (P<0.05). In addition, the survival of patients with high LncRNA GAS5 expression was obviously superior to those with low LncRNA GAS5 expression (P<0.05), patients with negative Ki67 had superior survival than those with positive Ki67 (P<0.05), and patients with negative EGFR had increased survival over those with positive EGFR (P<0.05). Moreover, the positive rates of Ki67 and EGFR in patients with low LncRNA GAS5 expressions were obviously higher than those with high LncRNA GAS5 expressions (P<0.05). The relative expression level of LncRNA GAS5 in NSCLC patients had a remarkably negative correlation with Ki67 and EGFR (P<0.05).

CONCLUSION

The decrease in LncRNA GAS5 expression and the over-express of Ki67/EGFR occur in NSCLC tissues, the expressions of LncRNA GAS5, Ki67 and EGFR are connected with the progression, metastasis and prognosis of tumor; and LncRNA GAS5 is related to the expression of Ki67 and EGFR. These three factors are involved in the tumorigenesis and growth of the NSCLC process.

Relationship between long non-coding RNA PCAT-1 expression and gefitinib resistance in non-small-cell lung cancer cells

BACKGROUND

Gefitinib, an epidermal growth factor receptor tyrosine kinase inhibitor, has been used as first-line treatment for advanced non-small-cell lung cancer (NSCLC). However, during treatment, cancer cells often develop resistance to gefitinib, the mechanisms of which are not fully understood. This study was designed to elucidate the expression and role of long non-coding RNA (lncRNA)-PCAT-1, a potential biomarker for drug resistance and a therapeutic target for NSCLC, in gefitinib resistance in NSCLC cells.

METHODS

In this study, we verified differential PCAT-1 expression in NSCLC gefitinib-resistant tissues or cells. PCAT-1 knockdown, clone formation, Transwell, flow cytometry, and immunofluorescence assays were used to verify the correlation between PCAT-1 and gefitinib sensitivity. A nude mouse tumor-bearing model verified that PCAT-1 can reverse gefitinib resistance in vivo. Then, a PI3K/Akt agonist was used to verify the possible mechanism of PCAT-1 action.

RESULTS

PCAT-1 is highly expressed in gefitinib-resistant NSCLC tissues and cells. PCAT-1 knockdown enhanced gefitinib sensitivity and gefitinib-induced apoptosis in H1299/GR cells. PCAT-1 knockdown reduced tumor volume and weight, and reversed acquired gefitinib resistance in vivo. PCAT-1 knockdown inhibited AKT and GSK3 phosphorylation in H1299/GR cells. A PI3K/AKT agonist reversed PCAT-1 knockdown-mediated enhancement of gefitinib sensitivity in H1299/GR cells CONCLUSION: PCAT-1 knockdown improves sensitivity to gefitinib by inhibition of AKT and GSK3 phosphorylation in NSCLC. PCAT-1 is as potential target for improving the clinical efficacy of gefitinib.

Long noncoding RNA LMO7DN inhibits cell proliferation by regulating the cell cycle in lung adenocarcinoma

In our previous study, we reported that the long noncoding RNA, LMO7 downstream neighbor (LMO7DN), has a strong prognostic value in lung adenocarcinoma (LUAD). In this study, we further investigated the role of LMO7DN in LUAD progression. LMO7DN was found to be expressed at low levels in LUAD tissues, and its high expression predicted good prognosis. Bioinformatics analysis indicated that LMO7DN was closely associated with the cell cycle. Furthermore, we found that cell proliferation was significantly enhanced following knockdown of LMO7DN, and the number of cells in the G2/M phase was markedly decreased, whereas there was no change in apoptosis. Thus, LMO7DN inhibits cell proliferation by affecting the cell cycle and is of significant prognostic value in LUAD.

MicroRNA-32 and MicroRNA-548a Promote the Drug Sensitivity of Non-Small Cell Lung Cancer Cells to Cisplatin by Targeting ROBO1 and Inhibiting the Activation of Wnt/β-Catenin Axis

Background

The roles of microRNA (miR)-32 and miR-548a in non-small cell lung cancer (NSCLC) have been studied. But their influences on NSCLC cells to cisplatin (DDP) resistance remain elusive. This study estimated the mechanisms of miR-32 and miR-548a in NSCLC cells to DDP.

Methods

Differentially expressed miRs in DDP-sensitive and resistant tissues were screened out using a GSE56036 chip. Then the predictive efficacies of miR-32 and miR-548a on DDP resistance were analyzed in NSCLC patients. The target mRNAs of miR-548a and miR-32 were predicted. miR-548a and miR-32 were knocked down to assess the influences of miR-32 and miR-548a on NSCLC growth. DDP-resistant cells were constructed and miR-32 and miR-548a expression was detected in resistant cells. After miR-32 and miR-548a knockdown, the IC50 value of DDP was detected. Then, the activation level of Wnt/β-catenin pathway was detected. The roles of miR-32 and miR-548a in NSCLC growth in vivo were detected by tumorigenesis experiment.

Results

miR-32 and miR-548a were poorly expressed in DDP-resistant NSCLC. miR-32 and miR-548a mimic enhanced the DDP sensitivity of NSCLC cells. Both miR-32 and miR-548a targeted ROBO1, and overexpression of ROBO1 inhibited the promotion of miR-32 and miR-548a mimic on DDP sensitivity. ROBO1 activated the Wnt/β-catenin pathway, thus enhancing the DDP resistance.

Conclusion

miR-32 and miR-548a target ROBO1 and inhibit Wnt/β-catenin activation, thus promoting the drug sensitivity of NSCLC cells to DDP.

The function of LncRNAs and their role in the prediction, diagnosis, and prognosis of lung cancer

Lung cancer remains a major threat to human health. Low dose CT scan (LDCT) has become the main method of early screening for lung cancer due to the low sensitivity of chest X-ray. However, LDCT not only has a high false positive rate, but also entails risks of overdiagnosis and cumulative radiation exposure. In addition, cumulative radiation by LDCT screening and subsequent follow-up can increase the risk of lung cancer. Many studies have shown that long noncoding RNAs (lncRNAs) remain stable in blood, and profiling of blood has the advantages of being noninvasive, readily accessible and inexpensive. Serum or plasma assay of lncRNAs in blood can be used as a novel detection method to assist LDCT while improving the accuracy of early lung cancer screening. LncRNAs can participate in the regulation of various biological processes. A large number of researches have reported that lncRNAs are key regulators involved in the progression of human cancers through multiple action models. Especially, some lncRNAs can affect various hallmarks of lung cancer. In addition to their diagnostic value, lncRNAs also possess promising potential in other clinical applications toward lung cancer. LncRNAs can be used as predictive markers for chemosensitivity, radiosensitivity, and sensitivity to epidermal growth factor receptor (EGFR)-targeted therapy, and as well markers of prognosis. Different lncRNAs have been implicated to regulate chemosensitivity, radiosensitivity, and sensitivity to EGFR-targeted therapy through diverse mechanisms. Although many challenges need to be addressed in the future, lncRNAs have bright prospects as an adjunct to radiographic methods in the clinical management of lung cancer.

LncRNA OSER1-AS1 interacts with miR-612/FOXM1 axis to modulate gefitinib resistance of lung adenocarcinoma

Long noncoding RNAs (lncRNAs) play crucial roles in the acquired resistance to EGFR-directed therapies in lung cancer. LncRNA OSER1-AS1 has been reported to promote tumorigenesis of hepatocellular carcinoma. However, its functions and underlying molecular mechanisms remain unclear in the acquired gefitinib-resistance of lung cancer. Our study revealed that increased expression of OSER1-AS1 was correlated with gefitinib resistance in lung adenocarcinoma. Higher OSER1-AS1 expression predicted disease progression of lung adenocarcinoma patients. The in vitro assays indicated OSER1-AS1 contributed to gefitinib resistance of lung adenocarcinoma cells via inhibiting cell apoptosis and cell cycle arrest. In vivo experiments showed that the knockdown of OSER1-AS1 restored the sensitivity of lung cancer cells to gefitinib. Further studies showed that OSER1-AS1 functioned as a molecular sponge of miR-612. OSER1-AS1 down-regulated miR-612 to increase FOXM1 expression, suggesting that miR-612/FOXM1 axis was regulated by OSER1-AS1, which was partially responsible for gefitinib resistance of lung adenocarcinoma. In conclusion, OSER1-AS1 promoted gefitinib resistance of lung adenocarcinoma through the miR-612/FOXM1 axis.

LncRNA MITA1 promotes gefitinib resistance by inducing autophagy in lung cancer cells

Lung cancer is a major health challenge worldwide. Gefitinib, a tyrosine kinase inhibitor (TKI), is the common therapeutic drug used in advanced non-small-cell lung cancer (NSCLC). However, it is eventually bound to face the problem of acquired drug resistance. In this work, we investigated the role of lncRNA MITA1 in the acquisition of gefitinib resistance in NSCLC and uncovered the possible underlying molecular mechanism of the same. Experiments were carried out using the HCC827 and HCC827GR cells. These were transfected with pcDNA-MITA1 or si-MITA1 and treated with gefitinib. Subsequently, lncRNA MITA1 mediated effect on cell viability and apoptosis were studied using the MTT and flow cytometry assays. Furthermore, using qRT-PCR, Western blotting, and immunofluorescence assays, the regulatory association between lncRNA MITA1 and markers of autophagy (LC3, Beclin-1, and p62) were examined by estimating their cellular protein levels. Also, these results were verified in the presence of an autophagy inhibitor bafilomycin A1. We found that MITA1 was highly upregulated in the gefitinib-resistant NSCLC cells, indicating the regulatory role of MITA1 in gefitinib resistance. Mechanistically, upregulated MITA1 led to gefitinib resistance by suppressing apoptosis, increasing cell viability, and inducing autophagy. Furthermore, these results were true when tested in the presence of bafilomycin A1. Our results suggest that MITA1 by inducing autophagy could be a key regulator of gefitinib resistance in NSCLC.

Downregulation of long non‑coding RNA GACAT1 suppresses proliferation and induces apoptosis of NSCLC cells by sponging microRNA‑422a

Increasing evidence has demonstrated the important roles of long non‑coding (lnc) RNA in non‑small cell lung cancer (NSCLC). lncRNA gastric cancer‑associated transcript 1 (GACAT1) has been reported to play an oncogenic role in different types of cancer; however, the function of GACAT1 in NSCLC remains unclear. The present study found that GACAT1 was overexpressed in NSCLC tissues and was associated with poor outcomes in patients with NSCLC. Functional experiments revealed that GACAT1 downregulation inhibited proliferation, induced apoptosis and cell cycle arrest of 2 NSCLC cell lines. GACAT1 was found to target microRNA(miR)‑422a mechanically and negatively regulated miR‑422a expression. Reduced expression of miR‑422a in NSCLC tissues was inversely correlated with that of GACAT1. Furthermore, YY1 transcription factor (YY1) was identified as a downstream miR‑422a target. Reduced expression of GACAT1 inactivated YY1 by sponging miR‑422a in NSCLC cells. YY1 reintroduction reversed the reduced proliferation of NSCLC cells via GACAT1 knockdown. Taken together, these results revealed the novel role of the GACAT1/miR‑422a pathway in the progression of NSCLC cell lines, providing a possible therapeutic strategy for NSCLC treatment.

LncRNA SNHG14 regulates the DDP-resistance of non-small cell lung cancer cell through miR-133a/HOXB13 pathway

Background

Recently, long non-coding RNAs (lncRNAs) have been reported to be involved in regulating chemo-resistance of NSCLC, however, the role of lncRNA SNHG14 in the DDP-resistance of NSCLC remains unexplored.

Methods

Relative expression of SNHG14, HOXB13 and miR-133a in DDP-resistant A549 (A549/DDP) cell and its parental cell A549 were measured using qRT-PCR. Cell proliferation viability of indicated A549/DDP cell was estimated via CCK-8 and colony formation experiments. Cell cycle and apoptosis were analyzed through flow cytometry. Expression of apoptosis-related protein and HOXB13 were detected via western blot. The interaction among SNHG14, HOXB13 and miR-133a was predicted by bioinformatics and validated by dual-luciferase reporter assay.

Results

LncRNA SNHG14 and HOXB13 were upregulated while miR-133a was downregulated in A549/DDP cell line compared to A549 cell line. SNHG14 knockdown or miR-133a overexpression was demonstrated to increase the DDP-sensitivity of A549/DDP cells. SNHG14 was revealed to compete with HOXB13 for miR-133a binding in A549/DDP cells. Inhibition of miR-133a in A549 cells could reverse the promotive effects of SNHG14 knockdown on DDP-sensitivity, as well as the inhibitory effects on HOXB13 expression. HOXB13 overexpression was revealed to abolish the enhanced effects of miR-133a on the sensitivity of A549/DDP cell to DDP.

Conclusion

Our findings demonstrated that SNHG14 was involved in the development of DDP-resistance of A549/DDP cells through miR-133a/HOXB13 axis, which may present a path to novel therapeutic stratagems for DDP resistance of NSCLC.

New insights into long non-coding RNAs in non-small cell lung cancer

Lung cancer is a malignant tumor that seriously threatens human life and health. Non-small cell lung cancer (NSCLC) accounts for 85 % of all lung cancer cases, and its global 5-year survival rate is only approximately 5%. Thus, the identification of new prognostic biomarkers has become one of the most urgent challenges in NSCLC research. Long noncoding RNAs (LncRNAs) are a kind of noncoding RNA whose length exceeds 200 nucleotides (nt). LncRNAs are transcribed by RNA pol II and can be subjected to posttranscriptional modifications such as blocking, polyadenylation and splicing; moreover, their expression profiles are more specific than those of mRNAs. Emerging evidence confirms that lncRNAs are associated with the occurrence and development of NSCLC and play an important role in NSCLC drug resistance. The purpose of this review was to describe the roles of lncRNAs in the development, diagnosis and prognosis of NSCLC and to explore new evidence of lncRNAs in the treatment of NSCLC drug resistance. This review provides a new perspective of lncRNAs in the treatment of NSCLC.

LncRNA LINC01116 Contributes to Cisplatin Resistance in Lung Adenocarcinoma

Background

Long non-coding RNAs (lncRNAs) have been found to contribute to cisplatin resistance in several cancers; however, the role of lncRNA LINC01116 in cisplatin resistance remains unknown in non-small-cell lung cancer. This study aimed to examine the contribution of LINC01116 to cisplatin resistance in lung adenocarcinoma (LAD).

Materials and Methods

Cisplatin-resistant A549/DDP cells were generated by treatment with cisplatin by dose escalation. LINC01116 expression was compared between A549 and A549/DDP cells, and between cisplatin-resistant and non-resistant LAD specimens. The cell viability, colony formation, proliferation, migration and invasion were measured using MTT and Transwell assays, and cell apoptosis and cell cycle were detected using flow cytometry. The expression of E-cadherin and Vimentin was quantified. LAD xenografts were modeled in nude mice to investigate the role of LINC01116 on the resistance of LAD to cisplatin.

Results

MTT assay measured the IC₅₀ values of 13.49 ± 1.62 and 3.52 ± 1.33 μg/mL for A549/DDP and A549 cells, respectively. LINC01116 was overexpressed in cisplatin-resistant LAD specimens and A549/DDP cells (P < 0.05). Knockdown of LINC01116 inhibited cell viability, proliferation, migration and invasion, promoted apoptosis and enhanced the sensitivity to cisplatin in A549/DDP cells, while LINC01116 overexpression promoted cell viability, proliferation, migration and invasion, inhibited apoptosis and reduced the sensitivity to cisplatin in A549 cells. LINC01116 knockdown resulted in a 2.1-fold increase in E-cadherin expression and a 56% reduction in Vimentin expression in A549/DDP cells, and LINC01116 overexpression resulted in a 45% reduction in E-cadherin expression and a 1.82-fold increase in Vimentin expression in A549 cells.

Conclusion

Dysregulation of lncRNA LINC01116 expression results in resistance of LAD to cisplatin via the EMT process. Our findings support the oncogenic role of LINC01116 to promote the development of cisplatin resistance in LAD, and LINC01116 may be a novel predictor of poor response to cisplatin.

Genomics and Transcriptomics: The Powerful Technologies in Precision Medicine

In a clinical trial, people with the same disease can show different responses after treatment with the same drug and exactly under the same conditions. Some of them may improve, some may not show any response, and occasionally side effects may be observed. In other words, people with the same disease process under the same therapeutic conditions may have different responses. Today, some diseases are resistant to conventional (standard) treatment procedures. Why do people with the same disease show different responses to the treatment with the same drug? This is primarily due to differences in molecular pathways (especially genetic variations) associated with the disease. On the other hand, designing and delivery of a new drug is a time-consuming and costly process, so any mistake in any stage of this process can have irreparable consequences for pharmaceutical companies and consumer patients. Therefore, we can achieve more accurate and reliable treatments by acquiring precise insight into different aspects of precision medicine including genomics and transcriptomics. The aim of this paper is to address the role of genomics and transcriptomics in precision medicine.

lncRNA RPPH1 promotes non-small cell lung cancer progression through the miR-326/WNT2B axis

Long non-coding RNAs (lncRNAs) serve important regulatory roles in human tumors. The aim of the present study was to examine the role of ribonuclease P RNA component H1 (RPPH1) in non-small cell lung cancer (NSCLC). RPPH1 expression was assessed in datasets from The Cancer Genome Atlas, as well as lung cancer cell lines and patients with NSCLC. RPPH1 was significantly upregulated in NSCLC cell lines, compared with a normal lung epithelial cell line. Moreover, high RPPH1 expression was associated with poor overall survival and disease progression. RPPH1 was knocked down in A549 and H1299 cells using short hairpin (sh) RNA constructs, and the expressions of target genes and proteins were determined by reverse transcription-quantitative PCR and western blotting. Cell invasion potential was also determined using Transwell Matrigel assays. Compared with the negative control, RPPH1 silencing significantly reduced the number of invading cells, increased E-cadherin expression and reduced vimentin protein expression. Cell resistance to cisplatin/cis-diamminedichloridoplatinum (CDDP) was also evaluated using Cell Counting Kit-8 and colony formation assays. RPPH1 overexpression increased the resistance of A549 and H1299 cells to CDDP. Moreover, the potential interactions between RPPH1, microRNA (miR)-326 and Wnt family member 2B (WNT2B) were investigated using luciferase reporter assays and co-transfection experiments. MiR-326 expression was directly inhibited by RPPH1. In A549 cells co-transfected with shRPPH1 and miR-326 inhibitor, the invading cell number significantly increased compared with cells transfected with shRPPH1 alone. In addition, E-cadherin expression levels were reduced, and vimentin was upregulated. MiR-326 overexpression partially reduced the resistance of A549 cells to CDDP induced by RPPH1 overexpression. WNT2B expression was directly suppressed using miR-326. A549 cells co-transfected with a miR-326 mimic and a WNT2B overexpression vector demonstrated increased invasion potential, reduced E-cadherin and increased vimentin protein expression levels, compared with cells transfected with the mimic alone. miR-326 overexpression reduced CDDP resistance in A549 cells. However, co-transfection with WNT2B partially enhanced CDDP resistance, compared with the mimic alone. In conclusion, RPPH1 promoted NSCLC progression and lung cancer cell resistance to CDDP through miR-326 and WNT2B.

Long noncoding RNA PSMA3‑AS1 functions as a microRNA‑409‑3p sponge to promote the progression of non‑small cell lung carcinoma by targeting spindlin 1

PSMA3 antisense RNA 1 (PSMA3‑AS1), a long noncoding RNA, promotes the progression of esophageal squamous cell carcinoma. However, no study to date has explored the expression or roles of PSMA3‑AS1 in non‑small cell lung carcinoma (NSCLC). The present study examined the expression profile and role of PSMA3‑AS1 in NSCLC. It also aimed to identify how PSMA3‑AS1 promotes the malignant phenotype of NSCLC cells. PSMA3‑AS1 expression in NSCLC tissues and cell lines was measured by reverse transcription‑quantitative polymerase chain reaction. Cell Counting Kit‑8, cell apoptosis, Transwell migration and invasion, and xenograft tumor assays were conducted to study the effects of PSMA3‑AS1 on the aggressive phenotype of NSCLC cells. Furthermore, bioinformatics analysis, RNA immunoprecipitation, luciferase reporter assay, western blotting, and rescue experiments were used to elucidate the interaction among PSMA3‑AS1, microRNA‑409‑3p (miR‑409‑3p), and spindlin 1 (SPIN1) in NSCLC cells. In the present study, high levels of PSMA3‑AS1 were confirmed in both NSCLC tissues and cell lines. An increased PSMA3‑AS1 level was correlated with advanced tumor‑node‑metastasis stage and increased lymph node metastasis. Patients with NSCLC with high PSMA3‑AS1 levels had shorter overall survival than those with low PSMA3‑AS1 levels. PSMA3‑AS1 depletion significantly decreased NSCLC cell proliferation, migration, and invasion, as well as substantially increased cell apoptosis in vitro. Furthermore, PSMA3‑AS1 deficiency decreased NSCLC tumor growth in vivo. Through molecular mechanism assays, it was revealed that PSMA3‑AS1 acted as a molecular sponge for miR‑409‑3p and consequently increased SPIN1 expression. Notably, rescue experiments revealed that the inhibition of miR‑409‑3p or restoration of SPIN1 expression abrogated the effects of PSMA3‑AS1 knockdown in NSCLC cells. Collectively, PSMA3‑AS1 functioned as an oncogenic long noncoding RNA in NSCLC. PSMA3‑AS1 sponged miR‑409‑3p and thus increased SPIN1 expression, promoting the aggressive phenotype of NSCLC cells.

LncRNA UCA1 Induces Acquired Resistance to Gefitinib by Epigenetically Silencing CDKN1A Expression in Non-small-Cell Lung Cancer

Lung cancer is the most common cancer globally and is associated with high morbidity and mortality. Gefitinib has been widely used for treating advanced non-small-cell lung cancer (NSCLC). However, acquired resistance usually develops, although we still know little about the mechanism underlying this. In the present study, we found that the lncRNA UCA1 was upregulated in NSCLC tissues and cells with acquired gefitinib resistance, indicating the special role of UCA1 in gefitinib resistance. Knockdown of UCA1 promoted the sensitivity to gefitinib both in vitro and in vivo by suppressing cell proliferation and inducing apoptosis. Moreover, UCA1 could interact with EZH2 (enhancer of zeste homolog 2) to epigenetically reduce the expression of CDKN1A. Taking the obtained findings together, our study suggests that UCA1 is important for NSCLC to develop gefitinib resistance, and is a potential biomarker for gefitinib resistance and a therapeutic target for advanced NSCLC.

Long Non-Coding RNA HOTAIR in Breast Cancer Therapy

Breast cancer (BC) is the most common cancer type among women, and morbidity and mortality rates are still very high. Despite new innovative therapeutic approaches for all BC molecular subtypes, the discovery of new molecular biomarkers involved in tumor progression has been fundamental for the implementation of personalized treatment strategies and improvement of patient management. Many experimental studies indicate that long non-coding RNAs (lncRNAs) are strongly involved in BC initiation, metastatic progression, and drug resistance. In particular, aberrant expression of HOX transcript antisense intergenic RNA (HOTAIR) lncRNA plays an important role in BC contributing to its progression and represents a predictor of BC metastasis. For its proven prognostic value, HOTAIR could represent a potential therapeutic target in BC. In the present review, we summarize the role of HOTAIR in cancer progression and drug resistance, in particular in BC, and we illustrate the main approaches for silencing it.

Long non-coding RNAs regulate drug resistance in cancer

Chemoresistance, whether intrinsic or acquired, is a major obstacle in the treatment of cancer. The resistance of cancer cells to chemotherapeutic drugs can result from various mechanisms. Over the last decade, it has been reported that 1ong noncoding RNAs (lncRNAs) can mediate carcinogenesis and drug resistance/sensitivity in cancer cells. This article reviews, in detail, recent studies regarding the roles of lncRNAs in mediating drug resistance.

Long non-coding RNAs regulate drug resistance in cancer

Chemoresistance, whether intrinsic or acquired, is a major obstacle in the treatment of cancer. The resistance of cancer cells to chemotherapeutic drugs can result from various mechanisms. Over the last decade, it has been reported that 1ong noncoding RNAs (lncRNAs) can mediate carcinogenesis and drug resistance/sensitivity in cancer cells. This article reviews, in detail, recent studies regarding the roles of lncRNAs in mediating drug resistance.

PVT1 Promotes the Proliferation and Migration of Non-Small Cell Lung Cancer via Regulating miR-148/RAB34 Signal Axis

Objective

It has been verified that long non-coding RNAs (lncRNAs) play critical roles in the development of human cancers. Increasing evidence indicates that lncRNA human plasmacytoma variant translocation1 (PVT1) was dysregulated in non-small cell lung cancer (NSCLC) which is the leading cause of cancer-related death. However, the precise mechanism underlying the effect of PVT1 remains elusive. Our research focused on the correlation of PVT1 to miR-148 and RAB34 in NSCLC.

Methods

The quantitative real-time PCR (qRT-PCR) and western blot assay were used to detect gene and protein expression in NSCLC tissues and cells. CCK8, colony formation, transwell and wound healing assays were performed to evaluate the cell function of NSCLC cells. Dual-luciferase activity assay and RNA pull down assays were performed to verify the interaction between miR-148 and its targets. A xenograft test was conducted to detect the impact of RAB34 on tumor development in vitro.

Results

In NSCLC tissues and cells, PVT1 and RAB34 were up-regulated, and miR-148 was down-regulated. Overexpression of PVT1 was capable of promoting NSCLC cell proliferation and migration which could be reversed by miR-148 restoration or RAB34 knock down. Also, our data firstly determined that the down-regulation of RAB34 had inhibitor effects while the up-regulation of RAB34 had promotive effects on tumor growth in vitro and in vivo.

Conclusion

Those findings indicated that the signal pathway PVT1/miR-148/RAB34 play critical roles in the progression of NSCLC could be proposed in NSCLC as a possible diagnosis or therapeutic targets.

MiRNAs and LncRNAs: Dual Roles in TGF-β Signaling-Regulated Metastasis in Lung Cancer

Lung cancer is one of the most malignant cancers around the world, with high morbidity and mortality. Metastasis is the leading cause of lung cancer deaths and treatment failure. MicroRNAs (miRNAs) and long non-coding RNAs (lncRNAs), two groups of small non-coding RNAs (nc-RNAs), are confirmed to be lung cancer oncogenes or suppressors. Transforming growth factor-β (TGF-β) critically regulates lung cancer metastasis. In this review, we summarize the dual roles of miRNAs and lncRNAs in TGF-β signaling-regulated lung cancer epithelial-mesenchymal transition (EMT), invasion, migration, stemness, and metastasis. In addition, lncRNAs, competing endogenous RNAs (ceRNAs), and circular RNAs (circRNAs) can act as miRNA sponges to suppress miRNAs, thereby mediating TGF-β signaling-regulated lung cancer invasion, migration, and metastasis. Through this review, we hope to cast light on the regulatory mechanisms of miRNAs and lncRNAs in TGF-β signaling-regulated lung cancer metastasis and provide new insights for lung cancer treatment.

FKBP51 induces p53-dependent apoptosis and enhances drug sensitivity of human non-small-cell lung cancer cells

Lung cancer is one of the most prevalent cancer types worldwide, and non-small-cell lung cancer (NSCLC) accounts for ~85% of all lung cancer cases. Despite the notable prevalence of NSCLC, the mechanisms underlying its progression remain unclear. The present study investigated the involvement of FK506-binding protein 51 (FKBP51) in NSCLC development and determined the factors associated with FKBP51 modification for NSCLC treatment. Immunohistochemical analysis was performed to analyze FKBP51 expression in human NSCLC tissue samples. Additionally, flow cytometry was performed to observe the apoptosis of FKBP51-overexpressing A549 cells. A dual-luciferase reporter assay was performed to confirm the association between FKBP51 and p53 expression, and western blotting was performed to analyze the effects of FKBP51 on the p53 signaling pathway. Finally, cell viability was measured using a Cell Counting Kit-8 assay. The results suggested FKBP51 downregulation in human lung cancer. Furthermore, apoptosis rates may be increased in FKBP51-overexpressing A549 cells. Moreover, FKBP51 promoted p53 expression and subsequent p53 signaling pathway activation. These results indicated that FKBP51 promoted A549 cell apoptosis via the p53 signaling pathway. Additionally, FKBP51 enhanced the sensitivity of A549 cells to cisplatin. Collectively, these data suggested that FKBP51 could serve as a biomarker for human lung cancer and can thus be tailored for incorporation into NSCLC therapy in the future.

Long noncoding RNA VPS9D1-AS1 augments the malignant phenotype of non-small cell lung cancer by sponging microRNA-532-3p and thereby enhancing HMGA2 expression

We investigated the influence of the long noncoding RNA VPS9D1 antisense RNA 1 (VPS9D1-AS1) on the malignant phenotype of non-small cell lung cancer (NSCLC) cells in vitro and in vivo. We also explored the mechanisms by which VPS9D1-AS1 exerts its oncogenic action during NSCLC progression. VPS9D1-AS1 expression was upregulated in NSCLC; the extent of its upregulation significantly correlated with patients’ adverse clinicopathological characteristics and shorter overall survival. When VPS9D1-AS1 was knocked down in NSCLC cells, their proliferation, colony-forming capacity, migration, and invasiveness were lower, whereas their apoptosis rate was higher, compared to the control. VPS9D1-AS1 knockdown attenuated tumor growth of NSCLC cells in vivo. Mechanistically, VPS9D1-AS1 directly interacted with microRNA-532-3p (miR-532-3p) in NSCLC cells; the impact of VPS9D1-AS1 knockdown on NSCLC cells was attenuated by miR-532-3p inhibition. Furthermore, VPS9D1-AS1 knockdown decreased the expression of high mobility group AT-hook 2 (HMGA2) in NSCLC cells via miR-532-3p sponging. Recovery of HMGA2 expression partially reversed the inhibitory effects of VPS9D1-AS1 knockdown on NSCLC cells. Thus, VPS9D1-AS1 functions as a competing endogenous RNA that positively regulates HMGA2 expression by sponging miR-532-3p in NSCLC cells, suggesting that the VPS9D1-AS1–miR-532-3p–HMGA2 pathway can be a potential diagnostic and/or therapeutic target in NSCLC.

Long Non-Coding RNA in Drug Resistance of Non-Small Cell Lung Cancer: A Mini Review

Lung cancer is one of main causes of cancer mortality and 83% of lung cancer cases are classified as non-small cell lung cancer (NSCLC). Patients with NSCLC usually have a poor prognosis and one of the leading causes is drug resistance. With the progress of drug therapy, the emergence and development of drug resistance affected the prognosis of patients severely. Accumulating evidence reveals that long non-coding RNAs (lncRNAs), as “dark matters” of the human genome, is of great significance to drug resistance in NSCLC. Herein, we review the role of lncRNAs in drug resistance in NSCLC.

miR-324-5p upregulation potentiates resistance to cisplatin by targeting FBXO11 signalling in non-small cell lung cancer cells

Dysregulation of microRNAs (miRNAs) plays a key role during the pathogenesis of chemoresistance in lung cancer (LCa). Previous study suggests that miR-324-5p may serve as a unique miRNA signature for LCa, but its role and the corresponding molecular basis remain largely explored. Herein, we report that miR-324-5p expression was significantly increased in cisplatin (CDDP)-resistant LCa tissues and cells, and this upregulation predicted a poor post-chemotherapy prognosis in LCa patients. miR-324-5p was further shown to impact CDDP response: Ectopic miR-324-5p expression in drug-naïve LCa cells was sufficient to attenuate sensitivity to CDDP and to confer more robust tumour growth in CDDP-challenged nude mice. Conversely, ablation of miR-324-5p expression in resistant cells effectively potentiated CDDP-suppressed cell growth in vitro and in vivo. Using multiple approaches, we further identified the tumour suppressor FBXO11 as the direct down-stream target of miR-324-5p. Stable expression of FBXO11 could abrogate the pro-survival effects of miR-324-5p in CDDP-challenged LCa cells. Together, these findings suggest that miR-324-5p upregulation mediates, at least partially, the CDDP resistance by directly targeting FBXO11 signalling in LCa cells. In-depth elucidation of the molecular basis underpinning miR-324-5p action bears potential implications for mechanism-based strategies to improve CDDP responses in LCa.

RNAactDrug: a comprehensive database of RNAs associated with drug sensitivity from multi-omics data

Drug sensitivity has always been at the core of individualized cancer chemotherapy. However, we have been overwhelmed by large-scale pharmacogenomic data in the era of next-generation sequencing technology, which makes it increasingly challenging for researchers, especially those without bioinformatic experience, to perform data integration, exploration and analysis. To bridge this gap, we developed RNAactDrug, a comprehensive database of RNAs associated with drug sensitivity from multi-omics data, which allows users to explore drug sensitivity and RNA molecule associations directly. It provides association data between drug sensitivity and RNA molecules including mRNAs, long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) at four molecular levels (expression, copy number variation, mutation and methylation) from integrated analysis of three large-scale pharmacogenomic databases (GDSC, CellMiner and CCLE). RNAactDrug currently stores more than 4 924 200 associations of RNA molecules and drug sensitivity at four molecular levels covering more than 19 770 mRNAs, 11 119 lncRNAs, 438 miRNAs and 4155 drugs. A user-friendly interface enriched with various browsing sections augmented with advance search facility for querying the database is offered for users retrieving. RNAactDrug provides a comprehensive resource for RNA molecules acting in drug sensitivity, and it could be used to prioritize drug sensitivity-related RNA molecules, further promoting the identification of clinically actionable biomarkers in drug sensitivity and drug development more cost-efficiently by making this knowledge accessible to both basic researchers and clinical practitioners. Database URL: http://bio-bigdata.hrbmu.edu.cn/RNAactDrug.

Long Noncoding RNA LINC01116 Contributes to Gefitinib Resistance in Non-small Cell Lung Cancer through Regulating IFI44

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs), such as gefitinib, have been established as first-line treatments for non-small cell lung cancer (NSCLC) patients and have exhibited notable clinical efficacy. However, resistance to TKIs has become one of the major obstacles in improving the therapeutic efficacy of patients with NSCLC. This study aims to investigate the role of the long non-coding RNA (lncRNA) LINC01116 in gefitinib resistance of NSCLC and explore its underlying mechanism. In this study, we found that LINC01116 is upregulated in the gefitinib-resistant NSCLC cells and tissues. Loss- and gain-of-function assays uncovered that LINC01116 downregulation sensitized gefitinib resistance, whereas the overexpression of LINC01116 conferred PC9/R cells to gefitinib treatment. Moreover, LINC01116 silencing increased IFI44 expression. Overexpression of IFI44 reversed the resistance to gefitinib in PC9/R cells, and rescue experiments confirmed that LINC01116 affects the gefitinib resistance of PC9/R cells partly dependent on regulating IFI44 expression. Moreover, downregulation of LINC01116 increased the sensitivity of PC9/R cells to gefitinib in vivo. Our study demonstrates that LINC01116 plays a critical role in gefitinib resistance of NSCLC cells by affecting IFI44 expression, providing a novel therapeutic target to overcome TKI resistance in NSCLC.