Inhibition of long non-coding RNA HOTAIR enhances radiosensitivity via regulating autophagy in pancreatic cancer

LncRNA HOTAIR promotes DNA damage repair and radioresistance by targeting ATR in colorectal cancer

Long non-coding RNAs (lncRNAs) have been implicated in cancer progression and drug resistance development. Moreover, there is evidence that lncRNA HOX transcript antisense intergenic RNA (HOTAIR) is involved in colorectal cancer (CRC) progression. The present study aimed to examine the functional role of lncRNA HOTAIR in conferring radiotherapy resistance in CRC cells, as well as the underlying mechanism. The relative expression levels of HOTAIR were examined in 70 pairs of CRC tumor and para-cancerous tissues, as well as in radiosensitive and radioresistant samples. The correlations between HOTAIR expression levels and clinical features of patients with CRC were assessed using the Chi-square test. Functional assays such as cell proliferation, colony formation and apoptosis assays were conducted to determine the radiosensitivity in CRC cells with HOTAIR silencing after treatment with different doses of radiation. RNA pull-down assay and fluorescence in situ hybridization (FISH) were used to determine the interaction between HOTAIR and DNA damage response mediator ataxia-telangiectasia mutated- and Rad3-related (ATR). HOTAIR was significantly upregulated in CRC tumor tissues, especially in radioresistant tumor samples. The elevated expression of HOTAIR was correlated with more advanced histological grades, distance metastasis and the poor prognosis in patients with CRC. Silencing HOTAIR suppressed the proliferation and promoted apoptosis and radiosensitivity in CRC cells. HOTAIR knockdown also inhibited the tumorigenesis of CRC cells and enhanced the sensitivity to radiotherapy in a mouse xenograft model. Moreover, the data showed that HOTAIR could interact with ATR to regulate the DNA damage repair signaling pathway. Silencing HOTAIR impaired the ATR-ATR interacting protein (ATRIP) complex and signaling in cell cycle progression. Collectively, the present results indicate that lncRNA HOTAIR facilitates the DNA damage response pathway and promotes radioresistance in CRC cells by targeting ATR.

The role of HOTAIR in the modulation of resistance to anticancer therapy

Leading anti-tumour therapeutic strategies typically involve surgery and radiotherapy for locally advanced (non-metastatic) cancers, while hormone therapy, chemotherapy, and molecular targeted therapy are the current treatment options for metastatic cancer. Despite the initially high sensitivity rate to anticancer therapies, a large number of patients develop resistance, leading to a poor prognosis. The mechanisms related to drug resistance are highly complex, and long non-coding RNAs appear to play a crucial role in these processes. Among these, the lncRNA homeobox transcript antisense intergenic RNA (HOTAIR), widely implicated in cancer initiation and progression, likewise plays a significant role in anticancer drug resistance. It can modulate cell activities such as proliferation, apoptosis, hypoxia, autophagy, as well as epithelial-mesenchymal transition, thereby contributing to the development of resistant tumour cells. In this manuscript, we describe different mechanisms of antitumor drug resistance in which HOTAIR is involved and suggest its potential as a therapeutic predictive biomarker for the management of cancer patients.

Critical role of the long non-coding RNAs (lncRNAs) in radiotherapy (RT)-resistance of gastrointestinal (GI) cancer: Is there a way to defeat this resistance?

Radiotherapy (RT) is a frequently used treatment for cervical cancer, effectively decreasing the likelihood of the disease returning in the same area and extending the lifespan of individuals with cervical cancer. Nevertheless, the primary reason for treatment failure in cancer patients is the cancer cells' resistance to radiation therapy (RT). Long non-coding RNAs (LncRNAs) are a subset of RNA molecules that do not code for proteins and are longer than 200 nucleotides. They have a significant impact on the regulation of gastrointestinal (GI) cancers biological processes. Recent research has shown that lncRNAs have a significant impact in controlling the responsiveness of GI cancer to radiation. This review provides a concise overview of the composition and operation of lncRNAs as well as the intricate molecular process behind radiosensitivity in GI cancer. Additionally, it compiles a comprehensive list of lncRNAs that are linked to radiosensitivity in such cancers. Furthermore, it delves into the potential practical implementation of these lncRNAs in modulating radiosensitivity in GI cancer.

Value of the HOTAIR expression assay in predicting therapy target in hepatocellular carcinoma: A meta-analysis and bioinformatics analysis

BACKGROUND

Several studies show that the long non-coding RNA HOX transcript antisense RNA (HOTAIR) was upregulated in human cancer, which was associated with several clinical features and may have the potential to be prognostic markers. However, the significance of HOTAIR in hepatocellular carcinoma remains unclear. We performed a meta-analysis and bioanalysis to further investigate the association between HOTAIR and hepatocellular carcinoma.

METHODS

Eligible literature was systematically retrieved from PubMed, Embase, and Web of Science databases. The pooled hazard ratios with 95% confidence intervals were used to evaluate to the effect. Raw data on HOTAIR expression were obtained from The Cancer Genome Atlas data portals. All bioinformatics analyses were performed using R software (version 4.3.1).

RESULTS

We identified eight studies in this meta-analysis with a total of 399 patients. High-level HOTAIR expression was found to be significantly related to advanced tumor node metastasis stage, distant metastasis, poor tumor differentiation, and patients with hepatitis. Correspondingly, HOTAIR was also associated with poor overall survival and relapse-free survival. Subsequently, in bioanalysis, HOTAIR expression was higher in hepatocellular carcinoma as well as poor overall survival. High HOTAIR expression was strongly correlated with tumor node metastasis stage. Kyoto Encyclopedia of Genes and Genomes analysis revealed that the differentially expressed genes related to HOTAIR may be involved in the cancer-associated signaling pathway.

CONCLUSION

HOTAIR may be a potential biomarker for HCC prediction and is expected to become a new choice for clinical HCC prediction..

LncRNAs as nodes for the cross-talk between autophagy and Wnt signaling in pancreatic cancer drug resistance

Pancreatic cancer is a malignancy with high mortality. In addition to the few symptoms until the disease reaches an advanced stage, the high fatality rate is attributed to its rapid development, drug resistance and lack of appropriate treatment. In the selection and research of therapeutic drugs, gemcitabine is the first-line drug for pancreatic cancer. Solving the problem of gemcitabine resistance in pancreatic cancer will contribute to the progress of pancreatic cancer treatment. Long non coding RNAs (lncRNAs), which are RNA transcripts longer than 200 nucleotides, play vital roles in cellular physiological metabolic activities. Currently, our group and others have found that some lncRNAs are aberrantly expressed in pancreatic cancer cells, which can regulate the process of cancer through autophagy and Wnt/β-catenin pathways simultaneously and affect the sensitivity of cancer cells to therapeutic drugs. This review presents an overview of the recent evidence concerning the node of lncRNA for the cross-talk between autophagy and Wnt/β-catenin signaling in pancreatic cancer, together with the practicability of lncRNAs and the core regulatory factors as targets in therapeutic resistance.

A bioinformatics analysis, pre-clinical and clinical conception of autophagy in pancreatic cancer: Complexity and simplicity in crosstalk

Pancreatic cancer (PC) is a serious gastrointestinal tract disease for which the 5-year survival rate is less than 10%, even in developed countries such as the USA. The genomic profile alterations and dysregulated biological mechanisms commonly occur in PC. Macroautophagy/autophagy is a cell death process that is maintained at a basal level in physiological conditions, whereas its level often changes during tumorigenesis. The function of autophagy in human cancers is dual and can be oncogenic and onco-suppressor. Autophagy is a potent controller of tumorigenesis in PC. The supportive autophagy in PC escalates the growth rate of PC cells and its suppression can mediate cell death. Autophagy also determines the metastasis of PC cells, and it can control the EMT in affecting migration. Moreover, starvation and hypoxia can stimulate glycolysis, and glycolysis induction can be mediated by autophagy in enhancing tumorigenesis in PC. Furthermore, protective autophagy stimulates drug resistance and gemcitabine resistance in PC cells, and its inhibition can enhance radiosensitivity. Autophagy can degrade MHC-I to mediate immune evasion and also regulates polarization of macrophages in the tumor microenvironment. Modulation of autophagy activity is provided by silibinin, ursolic acid, chrysin and huaier in the treatment of PC. Non-coding RNAs are also controllers of autophagy in PC and its inhibition can improve therapy response in patients. Moreover, mitophagy shows dysregulation in PC, which can enhance the proliferation of PC cells. Therefore, a bioinformatics analysis demonstrates the dysregulation of autophagy-related proteins and genes in PC as biomarkers.

Long Non-Coding RNAs and Metabolic Rewiring in Pancreatic Cancer

Pancreatic adenocarcinoma is a highly aggressive disease with a poor prognosis. The reprogramming of energetic metabolism has long been implicated in pancreatic tumorigenesis and/or resistance to treatment. Considering that long non-coding RNA dysregulation has been described both in cancerogenesis and in the altered homeostasis of several metabolic pathways, metabolism-associated lncRNAs can contribute to pancreatic cancer evolution. The objective of this review is to assess the burden of lncRNA dysregulation in pancreatic cancer metabolic reprogramming, and its effect on this tumor's natural course and response to treatment. Therefore, we reviewed the available literature to assess whether metabolism-associated lncRNAs have been found to be differentially expressed in pancreatic cancer, as well as whether experimental evidence of their role in such pathways can be demonstrated. Specifically, we provide a comprehensive overview of lncRNAs that are implicated in hypoxia-related pathways, as well as in the reprogramming of autophagy, lipid metabolism, and amino acid metabolism. Our review gathers background material for further research on possible applications of metabolism-associated lncRNAs as diagnostic/prognostic biomarkers and/or as potential therapeutic targets in pancreatic adenocarcinoma.

Roles of lncRNAs in pancreatic ductal adenocarcinoma: Diagnosis, treatment, and the development of drug resistance

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers, primarily due to its late diagnosis, high propensity to metastasis, and the development of resistance to chemo-/radiotherapy. Accumulating evidence suggests that long non-coding RNAs (lncRNAs) are intimately involved in the treatment resistance of pancreatic cancer cells via interacting with critical signaling pathways and may serve as potential diagnostic/prognostic markers or therapeutic targets in PDAC.

DATA SOURCES

We carried out a systematic review on lncRNAs-based research in the context of pancreatic cancer and presented an overview of the updated information regarding the molecular mechanisms underlying lncRNAs-modulated pancreatic cancer progression and drug resistance, together with their potential value in diagnosis, prognosis, and treatment of PDAC. Literature mining was performed in PubMed with the following keywords: long non-coding RNA, pancreatic ductal adenocarcinoma, pancreatic cancer up to January 2022. Publications relevant to the roles of lncRNAs in diagnosis, prognosis, drug resistance, and therapy of PDAC were collected and systematically reviewed.

RESULTS

LncRNAs, such as HOTAIR, HOTTIP, and PVT1, play essential roles in regulating pancreatic cancer cell proliferation, invasion, migration, and drug resistance, thus may serve as potential diagnostic/prognostic markers or therapeutic targets in PDAC. They participate in tumorigenesis mainly by targeting miRNAs, interacting with signaling molecules, and involving in the epithelial-mesenchymal transition process.

CONCLUSIONS

The functional lncRNAs play essential roles in pancreatic cancer cell proliferation, invasion, migration, and drug resistance and have potential values in diagnosis, prognostic prediction, and treatment of PDAC.

Non-coding RNAs in radiotherapy resistance: Roles and therapeutic implications in gastrointestinal cancer

Radiotherapy has become an indispensable and conventional means for patients with advanced solid tumors including gastrointestinal cancer. However, innate or acquired radiotherapy resistance remains a significant challenge and greatly limits the therapeutic effect, which results in cancer relapse and poor prognosis. Therefore, it is an urgent need to identify novel biomarkers and therapeutic targets for clarify the biological characteristics and mechanism of radiotherapy resistance. Recently, lots of studies have revealed that non-coding RNAs (ncRNAs) are the potential indicators and regulators of radiotherapy resistance via the mediation of various targets/pathways in different cancers. These findings may serve as a potential therapeutic strategy to overcome radiotherapy resistance. In this review, we will shed light on the recent findings regarding the functions and regulatory mechanisms of ncRNAs following radiotherapy, and comprehensively discuss their potential as biomarkers and therapeutic targets in radiotherapy resistance of gastrointestinal cancer.

The exciting encounter between lncRNAs and radiosensitivity in IR-induced DNA damage events

Radiation therapy is a commonly used tool in cancer management due to its ability to destroy malignant tumors. Mechanically, the efficacy of radiotherapy mainly depends on the inherent radiosensitivity of cancer cells and surrounding normal tissues, which mostly accounts for molecular dynamics associated with radiation-induced DNA damage. However, the relationship between radiosensitivity and DNA damage mechanism deserves to be further probed. As the well-established RNA regulators or effectors, long noncoding RNAs (lncRNAs) dominate vital roles in modulating ionizing radiation response by targeting crucial molecular pathways, including DNA damage repair. Recently, emerging evidence has constantly confirmed that overexpression or inhibition of lncRNAs can greatly influence the sensitivity of radiotherapy for many kinds of cancers, by driving a diverse array of DNA damage-associated signaling cascades. In conclusion, this review critically summarizes the recent progress in the molecular mechanism of IR-responsive lncRNAs in the context of radiation-induced DNA damage. The different response of lncRNAs when IR exposure. IR exposure can trigger the changes in expression pattern and subcellular localization of lncRNAs that influences the different radiology processes.

Molecular mechanisms of long noncoding RNAs associated with cervical cancer radiosensitivity

Despite advances in cervical cancer screening and human papilloma virus (HPV) vaccines, cervical cancer remains a global health burden. The standard treatment of cervical cancer includes surgery, radiation therapy, and chemotherapy. Radiotherapy (RT) is the primary treatment for advanced-stage disease. However, due to radioresistance, most patients in the advanced stage have an adverse outcome. Recent studies have shown that long noncoding RNAs (lncRNAs) participate in the regulation of cancer radiosensitivity by regulating DNA damage repair, apoptosis, cancer stem cells (CSCs), and epithelial-mesenchymal transition (EMT). In this review, we summarize the molecular mechanisms of long noncoding RNAs in cervical cancer and radiosensitivity, hoping to provide a theoretical basis and a new molecular target for the cervical cancer RT in the clinic.

HOX cluster-embedded lncRNAs and epithelial-mesenchymal transition in cancer: Molecular mechanisms and therapeutic opportunities

Although there has been substantial improvement in the treatment modalities, cancer remains the major cause of fatality worldwide. Metastasis, recurrence, and resistance to oncological therapies are the leading causes of cancer mortality. Epithelial-mesenchymal transition (EMT) is a complex biological process that allows cancer cells to undergo morphological transformation into a mesenchymal phenotype to acquire invasive potential. It encompasses reversible and dynamic ontogenesis by neoplastic cells during metastatic dissemination. Hence, understanding the molecular landscape of EMT is imperative to identify a reliable clinical biomarker to combat metastatic spread. Accumulating evidence reveals the role of HOX (homeobox) cluster-embedded long non-coding RNAs (lncRNAs) in EMT and cancer metastasis. They play a crucial role in the induction of EMT, modulating diverse biological targets. The present review emphasizes the involvement of HOX cluster-embedded lncRNAs in EMT as a molecular sponge, chromatin remodeler, signaling regulator, and immune system modulator. Furthermore, the molecular mechanisms behind therapy resistance and the potential use of novel drugs targeting HOX cluster-embedded lncRNAs in the clinical management of distant metastasis will be discussed.

Epigenetic regulation of autophagy by non-coding RNAs in gastrointestinal tumors: Biological functions and therapeutic perspectives

Cancer is the manifestation of changes and mutations in genetic and epigenetic levels. Non-coding RNAs (ncRNAs) are commonly dysregulated in disease pathogenesis, and their role in cancer has been well-documented. The ncRNAs regulate various molecular pathways and mechanisms in cancer that can lead to induction/inhibition of carcinogenesis. Autophagy is a molecular "self-digestion" mechanism its function can be pro-survival or pro-death in tumor cells. The aim of the present review is to evaluate the role of ncRNAs in regulating autophagy in gastrointestinal tumors. The role of the ncRNA/autophagy axis in affecting the progression of gastric, liver, colorectal, pancreatic, esophageal, and gallbladder cancers is investigated. Both ncRNAs and autophagy mechanisms can function as oncogenic or onco-suppressor and this interaction can determine the growth, invasion, and therapy response of gastrointestinal tumors. ncRNA/autophagy axis can reduce/increase the proliferation of gastrointestinal tumors via the glycolysis mechanism. Furthermore, related molecular pathways of metastasis, such as EMT and MMPs, are affected by the ncRNA/autophagy axis. The response of gastrointestinal tumors to chemotherapy and radiotherapy can be suppressed by pro-survival autophagy, and ncRNAs are essential regulators of this mechanism. miRNAs can regulate related genes and proteins of autophagy, such as ATGs and Beclin-1. Furthermore, lncRNAs and circRNAs down-regulate miRNA expression via sponging to modulate the autophagy mechanism. Moreover, anti-cancer agents can affect the expression level of ncRNAs regulating autophagy in gastrointestinal tumors. Therefore, translating these findings into clinics can improve the prognosis of patients.

Role of autophagy in tumor response to radiation: Implications for improving radiotherapy

Autophagy is an evolutionary conserved, lysosome-involved cellular process that facilitates the recycling of damaged macromolecules, cellular structures, and organelles, thereby generating precursors for macromolecular biosynthesis through the salvage pathway. It plays an important role in mediating biological responses toward various stress, including those caused by ionizing radiation at the cellular, tissue, and systemic levels thereby implying an instrumental role in shaping the tumor responses to radiotherapy. While a successful execution of autophagy appears to facilitate cell survival, abortive or interruptions in the completion of autophagy drive cell death in a context-dependent manner. Pre-clinical studies establishing its ubiquitous role in cells and tissues, and the systemic response to focal irradiation of tumors have prompted the initiation of clinical trials using pharmacologic modifiers of autophagy for enhancing the efficacy of radiotherapy. However, the outcome from the Phase I/II trials in many human malignancies has so far been equivocal. Such observations have not only precluded the advancement of these autophagy modifiers in the Phase III trial but have also raised concerns regarding their introduction as an adjuvant to radiotherapy. This warrants a thorough understanding of the biology of the cancer cells, including its spatio-temporal context, as well as its microenvironment all of which might be the crucial factors that determine the success of an autophagy modifier as an anticancer agent. This review captures the current understanding of the interplay between radiation induced autophagy and the biological responses to radiation damage as well as provides insight into the potentials and limitations of targeting autophagy for improving the radiotherapy of tumors.

Long noncoding RNAs (lncRNAs) in pancreatic cancer progression

Long noncoding RNAs (lncRNAs) are RNA molecules involved in gene regulation at transcriptional, post-transcriptional, and epigenetic levels. LncRNAs participate in regulating apoptosis and autophagy in pancreatic cancer (PCa) and can promote and/or decrease the proliferation rate of tumor cells. The metastasis of PCa cells is tightly regulated by lncRNAs and they can affect the mechanism of epithelial-mesenchymal transition (EMT) to modulate metastasis. The drug resistance of PCa cells, especially to gemcitabine, can be affected by lncRNAs. In addition, lncRNAs enriched in exosomes can be transferred among tumor cells to regulate their proliferation and metastasis. Antitumor compounds, such as curcumin and ginsenosides, can regulate lncRNA expression in PCa therapy. As we discuss here, the expression level of lncRNAs can be considered as both a diagnostic and prognostic tool in patients with PCa.

Emerging roles of long noncoding RNAs in chemoresistance of pancreatic cancer

Pancreatic cancer is one of the most common causes of cancer death in the world due to the lack of early symptoms, metastasis occurrence and chemoresistance. Therefore, early diagnosis by detection of biomarkers, blockade of metastasis, and overcoming chemoresistance are the effective strategies to improve the survival of pancreatic cancer patients. Accumulating evidence has revealed that long noncoding RNA (lncRNA) and circular RNAs (circRNAs) play essential roles in modulating chemosensitivity in pancreatic cancer. In this review article, we will summarize the role of lncRNAs in drug resistance of pancreatic cancer cells, including HOTTIP, HOTAIR, PVT1, linc-ROR, GAS5, UCA1, DYNC2H1-4, MEG3, TUG1, HOST2, HCP5, SLC7A11-AS1 and CASC2. We also highlight the function of circRNAs, such as circHIPK3 and circ_0000284, in regulation of drug sensitivity of pancreatic cancer cells. Moreover, we describe a number of compounds, including curcumin, genistein, resveratrol, quercetin, and salinomycin, which may modulate the expression of lncRNAs and enhance chemosensitivity in pancreatic cancers. Therefore, targeting specific lncRNAs and cicrRNAs could contribute to reverse chemoresistance of pancreatic cancer cells. We hope this review might stimulate the studies of lncRNAs and cicrRNAs, and develop the new therapeutic strategy via modulating these noncoding RNAs to promote chemosensitivity of pancreatic cancer cells.

Introduction of long non-coding RNAs to regulate autophagy-associated therapy resistance in cancer

Autophagy is a lysosomal degradation pathway that depends on various evolutionarily conserved autophagy-related genes (ATGs). Dysregulation of autophagy plays an important role in the occurrence and development of cancer. Chemotherapy, targeted therapy, radiotherapy, and immunotherapy are important treatment options for cancer, which can significantly improve the survival rate of cancer patients. However, the occurrence of therapy resistance results in therapeutic failure and poor prognosis of cancer. Accumulating studies have found that long non-coding RNAs (lncRNAs) are well known as crucial regulators to control autophagy through regulating ATGs and autophagy-associated signaling pathways, including the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling pathway, ultimately mediating chemoresistance and radioresistance. Taken together, this review systematically summarizes and elucidates the pivotal role of lncRNAs in cancer chemoresistance and radioresistance via regulating autophagy. Understanding the specific mechanism of which may provide autophagy-related therapeutic targets for cancer in the future.

Long Non-Coding RNAs in Pancreatic Cancer: Biologic Functions, Mechanisms, and Clinical Significance

Despite tremendous efforts devoted to research in pancreatic cancer (PC), the mechanism underlying the tumorigenesis and progression of PC is still not completely clear. Additionally, ideal biomarkers and satisfactory therapeutic strategies for clinical application in PC are still lacking. Accumulating evidence suggests that long non-coding RNAs (lncRNAs) might participate in the pathogenesis of diverse cancers, including PC. The abnormal expression of lncRNAs in PC is considered a vital factor during tumorigenesis that affects tumor cell proliferation, migration, invasion, apoptosis, angiogenesis, and drug resistance. With this review of relevant articles published in recent years, we aimed to summarize the biogenesis mechanism, classifications, and modes of action of lncRNAs and to review the functions and mechanisms of lncRNAs in PC. Additionally, the clinical significance of lncRNAs in PC was discussed. Finally, we pointed out the questions remaining from recent studies and anticipated that further investigations would address these gaps in knowledge in this field.

Non-coding RNAs underlying the pathophysiological links between type 2 diabetes and pancreatic cancer: A systematic review

Type 2 diabetes is known as a risk factor for pancreatic cancer (PC). Various genetic and environmental factors cause both these global chronic diseases. The mechanisms that define their relationships are complex and poorly understood. Recent studies have implicated that metabolic abnormalities, including hyperglycemia and hyperinsulinemia, could lead to cell damage responses, cell transformation, and increased cancer risk. Hence, these kinds of abnormalities following molecular events could be essential to develop our understanding of this complicated link. Among different molecular events, focusing on shared signaling pathways including metabolic (PI3K/Akt/mTOR) and mitogenic (MAPK) pathways in addition to regulatory mechanisms of gene expression such as those involved in non-coding RNAs (miRNAs, circRNAs, and lncRNAs) could be considered as powerful tools to describe this association. A better understanding of the molecular mechanisms involved in the development of type 2 diabetes and pancreatic cancer would help us to find a new research area for developing therapeutic and preventive strategies. For this purpose, in this review, we focused on the shared molecular events resulting in type 2 diabetes and pancreatic cancer. First, a comprehensive literature review was performed to determine similar molecular pathways and non-coding RNAs; then, the final results were discussed in more detail.

Mechanistic study of lncRNA UCA1 promoting growth and cisplatin resistance in lung adenocarcinoma

Aim

This study aimed to explore the mechanism of LncRNA urothelial carcinoma-associated 1 (UCA1) promoting cisplatin resistance in lung adenocarcinoma (LUAD).

Method

The UCA1 expression level in LUAD cell lines was detected by reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR). We overexpressed UCA1 in A549 cells and downregulated UCA1 in A549/DDP cells by the lentivirus‑mediated technique. Subsequently, in vitro, and in vivo functional experiments were performed to investigate the functional roles of UCA1 in the growth and metastasis of LUAD cell lines. Furthermore, RNA pulldown, mass spectrometry, and RNA immunoprecipitation technique were performed to analyze various downstream target factors regulated by UCA1.

Results

The results revealed a higher UCA1 expression level in A549/DDP cells and LUAD tissues than in A549 cells and adjacent cancer tissues. UCA1 expression was significantly associated with distant metastasis, clinical stage, and survival time of patients with LUAD. UCA1 overexpression significantly increased the proliferation, invasion, clone formation, and cisplatin resistance ability and enhanced the expression levels of proliferating cell nuclear antigen and excision repair cross-complementing gene 1 in A549 cells. However, these trends were mostly reversed after the knockdown of UCA1 in A549/DDP cells. Tumorigenic assays in nude mice showed that UCA1 knockdown significantly inhibited tumor growth and reduced cisplatin resistance. Enolase 1 was the RNA-binding protein (RBP) of UCA1.

Conclusion

Based on the results, we concluded that UCA1 promoted LUAD progression and cisplatin resistance and hence could be a potential diagnostic marker and therapeutic target in patients with LUAD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-02207-0.

LncRNA HOTAIR: A Potential Prognostic Factor and Therapeutic Target in Human Cancers

Long non-coding RNAs (lncRNAs) are emerging as crucial regulators of gene expression and physiological processes. LncRNAs are a class of ncRNAs of 200 nucleotides in length. HOX transcript antisense RNA (HOTAIR), a trans-acting lncRNA with regulatory function on transcription, can repress gene expression by recruiting chromatin modifiers. HOTAIR is an oncogenic lncRNA, and numerous studies have determined that HOTAIR is highly upregulated in a wide variety of human cancers. In this review, we briefly summarize the impact of lncRNA HOTAIR expression and functions on different human solid tumors, and emphasize the potential of HOTAIR on tumor prognosis and therapy. Here, we review the recent studies that highlight the prognostic potential of HOTAIR in drug resistance and survival, and the progress of therapies developed to target HOTAIR to date. Furthermore, targeting HOTAIR results in the suppression of HOTAIR expression or function. Thus, HOTAIR knockdown exhibits great therapeutic potential in various cancers, indicating that targeting lncRNA HOTAIR may serve as a promising strategy for cancer therapy. We also propose that preclinical studies involving HOTAIR are required to provide a better understanding of the exact molecular mechanisms underlying the dysregulation of its expression and function in different human cancers and to explore effective methods of targeting HOTAIR and engineering efficient and targeted drug delivery methods in vivo.

Non-coding RNAs in pancreatic ductal adenocarcinoma: New approaches for better diagnosis and therapy

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignancies with a 5-year survival rate less than 8%, which has remained unchanged over the last 50 years. Early detection is particularly difficult due to the lack of disease-specific symptoms and a reliable biomarker. Multimodality treatment including chemotherapy, radiotherapy (used sparingly) and surgery has become the standard of care for patients with PDAC. Carbohydrate antigen 19-9 (CA 19-9) is the most common diagnostic biomarker; however, it is not specific enough especially for asymptomatic patients. Non-coding RNAs are often deregulated in human malignancies and shown to be involved in cancer-related mechanisms such as cell growth, differentiation, and cell death. Several micro, long non-coding and circular RNAs have been reported to date which are involved in PDAC. Aim of this review is to discuss the roles and functions of non-coding RNAs in diagnosis and treatments of PDAC.

Preliminary screening and correlation analysis for lncRNAs related to radiosensitivity in melanoma cells by inhibiting glycolysis

OBJECTIVES

To screen the expression profiles of lncRNA and mRNA related to the radiosensitivity of melanoma cells by inhibiting glycolysis through microarray technology.

METHODS

WM35 melanoma cells were treated with different concentrations (1.25, 2.50, 5.00, 10.00 mmol/L) of 2-deoxy-D-glucose (2-DG) and different doses (0, 2, 4, 6, 8 Gy) of X-ray irradiation. MTT assay was used to detect the proliferation ability of NC-0 Gy group (negative control group), NC-4 Gy group (only 4 Gy X-ray irradiation), 2-DG group (only 2.50 mmol/L DG treatment), and 2-DG-4 Gy group (2.50 mmol/L 2-DG treatment, 4 Gy X-ray irradiation). Microarray chip was used to detect the changes in the expression profiles of lncRNA and mRNA in the NC-4 Gy group and the 2-DG-4 Gy group. Real-time RT-PCR was used to quantitatively detect the top 5 upregulated and the top 5 downregulated expression lncRNA. CNC analysis was used to predict potential target genes for the 10 most significantly expressed lncRNAs, after which the co-expression network of lncRNA and co-regulated mRNA were constructed. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were used to predict the functional distribution of differentially expressed lncRNA. Real-time RT-PCR was used to quantitatively detect the top 5 upregulated and the top 5 downregulated expression lncRNAs.

RESULTS

After 48 and 96 h, the cell proliferation of WM35 treated with 2-DG was significantly inhibited in a dose-dependent manner (all P<0.05). The cell proliferation of WM35 was inhibited by a high dose of X-ray irradiation, resulting in the death of mass cells. The cell proliferation activity of WM35 after 4 Gy X-ray irradiation descended 61% compared to the negative control group. Microarray analysis showed that there were 1 206 lncRNAs and 543 differentially expressed mRNAs between the NC-4 Gy group and the 2-DG-4 Gy group, while real-time RT-PCR showed basically consistent changes in lncRNA and mRNA microarray. Further CNC analysis showed that these 10 lncRNAs had a positive or negative correlation with 333 target genes. GO analysis was mainly concentrated in DNA binding, DNA damage repair, cell cycle arrest, and oxidative stress, while KEGG pathway analysis showed the 10 lncRNAs were related to radiosensitivity.

CONCLUSIONS

Microarray chip screens the expression profiles of differentially expressed lncRNA related to the radiosensitivity of melanoma cells via inhibiting glycolysis, and lncRNA RPL34-AS1 might be a potential biological target for melanoma radiotherapy.

Long noncoding RNAs: role and contribution in pancreatic cancer

Noncoding RNAs are proclaimed to be expressed in various cancer types and one such type is found to be pancreatic ductal adenocarcinoma (PDAC). The long noncoding RNAs (LncRNAs) affect the migration, invasion, and growth of tumor cells by playing important roles in the process of epigenesis, post-transcription, and transcriptional regulation along with the maintenance of apoptosis and cell cycle. It is quite subtle whether the alterations in lncRNAs would impact PDAC progression and development. This review throws a spotlight on the lncRNAs associated with tumor functions: MALAT-1, HOTAIR, HOXA13, H19, LINC01559, LINC00460, SNHG14, SNHG16, DLX6-AS1, MSC-AS1, ABHD11-AS1, DUXAP8, DANCR, XIST, DLEU2, etc. are upregulated lncRNAs whereas GAS5, HMlincRNA717, MIAT, LINC01111, lncRNA KCNK15-AS1, etc. are downregulated lncRNAs inhibiting the invasion and progression of PDAC. These data provided helps in the assessment of lncRNAs in the development, metastasis, and occurrence of PDAC and also play a vital role in the evolution of biomarkers and therapeutic agents for the treatment of PDAC.

Radiosensitizing effects of curcumin alone or combined with GLUT1 siRNA on laryngeal carcinoma cells through AMPK pathway-induced autophagy

In this study, we investigated the ability of curcumin alone or in combination with GLUT1 siRNA to radiosensitize laryngeal carcinoma (LC) through the induction of autophagy. Protein levels in tumour tissues and LC cells were measured by immunohistochemistry and Western blotting. In vitro, cell proliferation, colony formation assays, cell death and autophagy were detected. A nude mouse xenograft model was established through the injection of Tu212 cells. We found that GLUT1 was highly expressed and negatively associated with autophagy-related proteins in LC and that curcumin suppressed radiation-mediated GLUT1 overexpression in Tu212 cells. Treatment with curcumin, GLUT1 siRNA, or the combination of the two promoted autophagy. Inhibition of autophagy using 6-amino-3-methypourine (3-MA) promoted apoptosis after irradiation or treatment of cells with curcumin and GLUT1 siRNA. 3-MA inhibited curcumin and GLUT1 siRNA-mediated non-apoptotic programmed cell death. The combination of curcumin, GLUT1 siRNA and 3-MA provided the strongest sensitization in vivo. We also found that autophagy induction after curcumin or GLUT1 siRNA treatment implicated in the AMP-activated protein kinase-mTOR-serine/threonine-protein kinase-Beclin1 signalling pathway. Irradiation primarily caused apoptosis, and when combined with curcumin and GLUT1 siRNA treatment, the increased radiosensitivity of LC occurred through the concurrent induction of apoptosis and autophagy.

The Long Non-Coding RNA HOTAIR Is a Critical Epigenetic Mediator of Angiogenesis in Diabetic Retinopathy

Purpose

Diabetic retinopathy (DR) remains a pressing issue worldwide. Abnormal angiogenesis is a distinct vascular lesion in DR, and research has established that vascular endothelial growth factor A (VEGF-A) is a primary mediator of such changes. However, limitations in current anti-VEGF therapies suggest that our understanding of molecular networks underlying ocular angiogenesis remains far from complete. Based on our long non-coding RNA (lncRNA) array analyses, HOX antisense intergenic RNA (HOTAIR) was identified as one of the top upregulated lncRNAs in high glucose-cultured human retinal endothelial cells (HRECs). Given the well-documented roles of HOTAIR in cancer, no studies have examined the epigenetic implications of HOTAIR in DR, and we investigated such relationships herein.

Methods

We used HRECs exposed to various glucose concentrations and epigenetic modulators to examine HOTAIR, angiogenic, and DR-related molecular markers. Oxidative stress, angiogenesis, and mitochondrial dysfunction were assessed. Retinal tissues of diabetic rodents and the vitreous humor and serum of patients with proliferative DR were also investigated.

Results

Hyperglycemia significantly augmented HOTAIR expression in HRECs and promoted angiogenesis, oxidative damage, and mitochondrial aberrations. Similarly, vitreous humor and serum from proliferative DR patients and retinas from diabetic animals demonstrated increased HOTAIR expression compared to non-diabetic controls. HOTAIR knockdown protected against glucose-induced increases of angiogenic and diabetes-associated molecules in the retina. Mechanistically, we showed that HOTAIR exerts its capabilities by preventing oxidative stress and modulating epigenetic pathways involving histone methylation, histone acetylation, DNA methylation, and transcription factors.

Conclusions

Our findings suggest that HOTAIR is a critical lncRNA in the pathogenesis of DR and may potentially be important for diagnostic and therapeutic targeting.

Emerging role of non-coding RNAs in response of cancer cells to radiotherapy

Radiotherapy is an effective method for treatment of a large proportion of human cancers. Yet, the efficacy of this method is precluded by the induction of radioresistance in tumor cells and the radiation-associated injury of normal cells surrounding the field of radiation. These restrictions necessitate the introduction of modalities for either radiosensitization of cancer cells or protection of normal cells against adverse effects of radiation. Non-coding RNAs (ncRNAs) have essential roles in the determination of radiosensitivity. Moreover, ncRNAs can modulate radiation-induced side effects in normal cells. Several microRNAs (miRNAs) such as miR-620, miR-21 and miR-96-5p confer radioresistance, while other miRNAs including miR-340/ 429 confer radiosensitivity. The expression levels of a number of miRNAs are associated with radiation-induced complications such as lung fibrosis or oral mucositis. The expression patterns of several long non-coding RNAs (lncRNAs) such as MALAT1, LINC00630, HOTAIR, UCA1 and TINCR are associated with response to radiotherapy. Taken together, lncRNAs and miRNAs contribute both in modulation of response of cancer cells to radiotherapy and in protection of normal cells from the associated side effects. The current review provides an overview of the roles of these transcripts in these aspects.

Long Noncoding RNA PTPRG Antisense RNA 1 Reduces Radiosensitivity of Nonsmall Cell Lung Cancer Cells Via Regulating MiR-200c-3p/TCF4

Background:

PTPRG antisense RNA 1 has been well-documented to exert an oncogenic role in diverse neoplasms. However, the precise role of PTPRG antisense RNA 1 in regulating radiosensitivity of nonsmall cell lung cancer cells remains largely elusive.

Methods:

Expression levels of PTPRG antisense RNA 1 and miR-200c-3p in nonsmall cell lung cancer tissues and cells were detected by quantitative real-time polymerase chain reaction, while transcription factor 4 expression was examined by immunohistochemistry and Western blot. After nonsmall cell lung cancer cells were exposed to X-ray with different doses in vitro, Cell Counting Kit-8 assay and colony formation assay were conducted to determine the influence of PTPRG antisense RNA 1 on cell viability. Interaction between miR-200c-3p and PTPRG antisense RNA 1 as well as transcription factor 4 was investigated by dual luciferase reporter assay.

Result:

In nonsmall cell lung cancer tissues, the expressions of PTPRG antisense RNA 1 and transcription factor 4 were significantly upregulated, whereas the expression of miR-200c-3p was downregulated. It was also proved that PTPRG antisense RNA 1 and 3′-untranslated region of transcription factor 4 can bind to miR-200c-3p. Under X-ray irradiation, overexpressed PTPRG antisense RNA 1 could promote the viability and enhance the radioresistance of nonsmall cell lung cancer cells, and this effect was partially weakened by miR-200c-3p mimics. Transcription factor 4 was identified as a target gene of miR-200c-3p, which could be positively regulated by PTPRG antisense RNA 1.

Conclusion:

PTPRG antisense RNA 1 reduces the radiosensitivity of nonsmall cell lung cancer cells via modulating miR-200c-3p/TCF4 axis.

Therapeutic resistance of pancreatic cancer: Roadmap to its reversal

Pancreatic cancer is a lethal disease with limited opportunity for resectable surgery as the first choice for cure due to its late diagnosis and early metastasis. The desmoplastic stroma and cellular genetic or epigenetic alterations of pancreatic cancer impose physical and biological barriers to effective therapies, including chemotherapy, radiotherapy, targeted therapy, and immunotherapy. Here, we review the current therapeutic options for pancreatic cancer, and underlying mechanisms and potential reversal of therapeutic resistance, a hallmark of this deadly disease.

Non-Coding RNAs in Cancer Radiosensitivity: MicroRNAs and lncRNAs as Regulators of Radiation-Induced Signaling Pathways

Radiotherapy is a cancer treatment that applies high doses of ionizing radiation to induce cell death, mainly by triggering DNA double-strand breaks. The outcome of radiotherapy greatly depends on radiosensitivity of cancer cells, which is determined by multiple proteins and cellular processes. In this review, we summarize current knowledge on the role of microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), in determining the response to radiation. Non-coding RNAs modulate ionizing radiation response by targeting key signaling pathways, including DNA damage repair, apoptosis, glycolysis, cell cycle arrest, and autophagy. Additionally, we indicate miRNAs and lncRNAs that upon overexpression or inhibition alter cellular radiosensitivity. Current data indicate the potential of using specific non-coding RNAs as modulators of cellular radiosensitivity to improve outcome of radiotherapy.

HOTAIR drives autophagy in midbrain dopaminergic neurons in the substantia nigra compacta in a mouse model of Parkinson's disease by elevating NPTX2 via miR-221-3p binding

Parkinson’s disease (PD) is a neurodegenerative disorder characterized by progressive cell loss, largely confined to mesencephalic dopamine neurons of the substantia nigra. This study investigated the functional relevance of the HOX transcript antisense intergenic RNA (HOTAIR)/microRNA-221-3 (miR-221-3p)/neuronal pentraxin II (NPTX2) axis in the process of dopaminergic neuron autophagy using PD mouse models. The PD mouse models were established by intraperitoneal injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyrindine (MPTP), while PD cell model was constructed by pretreatment with 1-methyl-4-phenylpyridinium (MPP⁺). The expression of HOTAIR was then examined using RT-qPCR. In addition, the interactions between HOTAIR, miR-221-3p, and NPTX2 were detected through RIP and dual-luciferase reporter gene assays. CCK-8 assay was performed to measure cell viability, and the expression of autophagy-related genes was determined using Western blot analysis. HOTAIR was found to be significantly expressed in the substantia nigra compact tissues and MN9D cells following PD modeling. HOTAIR could bind to miR-221-3p and elevate the NPTX2 expression, which resulted in diminished cell viability and enhanced autophagy of dopaminergic neurons both in vitro and in vivo. In summary, down-regulation of HOTAIR could potentially inhibit the autophagy of dopaminergic neurons in the substantia nigra compacta in a mouse model of PD, thus saving the demise of dopaminergic neurons.

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 RNA HOTAIR knockdown enhances radiosensitivity through regulating microRNA-93/ATG12 axis in colorectal cancer

Colorectal cancer (CRC) is a global healthcare problem. Radioresistance is a huge setback for CRC radiotherapy. In this text, the roles and molecular mechanisms of long non-coding RNA HOTAIR in CRC tumorigenesis and radioresistance were further investigated. ATG12 mRNA, HOTAIR, and microRNA-93 (miR-93) levels were measured by quantitative reverse transcription polymerase chain reaction (RT-qPCR) assay. Protein levels of LC3 I, LC3 II, p62, ATG12, cleaved caspase 3, Bax, and Bcl-2 were detected by western blotting assay in cells and were examined by immunohistochemistry (IHC) assay in tissues. Cell survival fractions, viability, and apoptotic rates were determined by clonogenic survival assay, CCK-8 assay, and flow cytometry analysis, respectively. The relationships of HOTAIR, miR-93, and ATG12 were tested by bioinformatics analysis and luciferase reporter assay. Mouse xenograft tumor models were established to investigate the influence of HOTAIR knockdown on CRC radioresistance in vivo. We found that HOTAIR expression was markedly upregulated in plasma from CRC patients after radiotherapy and CRC cells after irradiation. HOTAIR knockdown, miR-93 overexpression, or ATG12 silencing weakened cell viability, induced cell apoptosis, inhibited cell autophagy, and enhanced cell radiosensitivity in CRC. HOTAIR exerted its functions by downregulating miR-93. Moreover, HOTAIR functioned as a molecular sponge of miR-93 to regulate ATG12 expression. ATG12 protein expression was markedly upregulated and associated with miR-93 and HOTAIR expression in CRC tissues. Furthermore, HOTAIR knockdown enhanced radiosensitivity of CRC xenograft tumors by regulating miR-93/ATG12 axis. In conclusion, HOTAIR knockdown potentiated radiosensitivity through regulating miR-93/ATG12 axis in CRC, further elucidating the roles and molecular basis of HOTAIR in CRC radioresistance.

Long non-coding RNA HOTAIR in cervical cancer: Molecular marker, mechanistic insight, and therapeutic target

Cervical cancer is a common gynecologic malignant tumor with high mortality. HOX transcript antisense RNA (HOTAIR), a trans-acting long non-coding RNA (lncRNA) containing six exons in humans, is transcribed from the antisense strand of homeobox gene C cluster. This lncRNA serves as a modular scaffold for gene silencing and protein ubiquitination. In patients with cervical cancer, elevated HOTAIR levels are significantly associated with poor prognosis. HOTAIR plays an oncogenic role in cervical cancer by promoting cell proliferation, migration, invasion and autophagy, inhibiting cell apoptosis, stimulating angiogenesis, accelerating cell cycle progression, and inducing epithelial-mesenchymal transition. Moreover, blockade of HOTAIR by artesunate or propofol shows promise for further development of this lncRNA as a potential therapeutic target in cervical cancer. In this review, we summarized the latest advances regarding the role of HOTAIR in cervical cancer with an emphasis on its diagnostic and prognostic values.

The multifaceted roles of long noncoding RNAs in pancreatic cancer: an update on what we know

Pancreatic cancer (PC) is one of the leading causes of cancer-related deaths worldwide. Due to the shortage of effective biomarkers for predicting survival and diagnosing PC, the underlying mechanism is still intensively investigated but poorly understood. Long noncoding RNAs (lncRNAs) provide biological functional diversity and complexity in protein regulatory networks. Scientific studies have revealed the emerging functions and regulatory roles of lncRNAs in PC behaviors. It is worth noting that some in-depth studies have revealed that lncRNAs are significantly associated with the initiation and progression of PC. As lncRNAs have good properties for both diagnostic and prognostic prediction due to their translation potential, we herein address the current understanding of the multifaceted roles of lncRNAs as regulators in the molecular mechanism of PC. We also discuss the possibility of using lncRNAs as survival biomarkers and their contributions to the development of targeted therapies based on the literature. The present review, based on what we know about current research findings, may help us better understand the roles of lncRNAs in PC.

Downregulated lncRNA-SNHG1 enhances autophagy and prevents cell death through the miR-221/222 /p27/mTOR pathway in Parkinson's disease

Autophagy has been shown to be critically associated with the central mechanisms underlying Parkinson's disease (PD), while the mechanisms contributing to the imbalance of autophagy remain unclear. Small nucleolar RNA host gene 1 (SNHG1), a well-studied long noncoding RNA, has been reported to be significantly increased in PD. The potential biological functions of SNHG1 in the regulation of neuronal autophagy and cell death in PD, however, have not yet been completely elucidated. In this study, we examined the existence of regulatory networks involving SNHG1, the miR-221/222 cluster and the cyclin-dependent kinase inhibitor 1B (CDKN1B/p27)/mammalian target of rapamycin (mTOR) signaling pathway in PD. We observed that SNHG1 expression was gradually upregulated in PD cellular and animal models. Furthermore, silencing SNHG1 promoted autophagy and prevented MPP⁺-induced cell death, similar to the overexpression of the miR-221/222 cluster. Mechanistically, SNHG1 competitively binds to the miR-221/222 cluster and indirectly regulates the expression of p27/mTOR. In conclusion, these results demonstrated that downregulation of SNHG1 attenuated MPP⁺-induced decreases in LC3-II (an autophagic marker) levels and cytotoxicity through the miR-221/222/p27/mTOR pathway, suggesting that SNHG1 may be a therapeutic target for neuroprotection and disease treatment in PD.

Molecular mechanisms of lncRNAs in regulating cancer cell radiosensitivity

Radiotherapy is one of the main modalities of cancer treatment. However, tumor recurrence following radiotherapy occurs in many cancer patients. A key to solving this problem is the optimization of radiosensitivity. In recent years, long non-coding RNAs (lncRNAs), which affect the occurrence and development of tumors through a variety of mechanisms, have become a popular research topic. LncRNAs have been found to influence radiosensitivity by regulating various mechanisms, including DNA damage repair, cell cycle arrest, apoptosis, cancer stem cells regulation, epithelial-mesenchymal transition, and autophagy. LncRNAs are expected to become a potential therapeutic target for radiotherapy in the future. This article reviews recent advances in the role and mechanism of lncRNAs in tumor radiosensitivity.

Research Progress on Long Non-Coding RNA and Radiotherapy

Long non-coding RNAs (lncRNAs), a group of non-protein-coding RNAs longer than 200 nucleotides, are involved in multiple biological and pathological processes, such as proliferation, apoptosis, migration, invasion, angiogenesis, and immune escape. Many studies have shown that lncRNAs participate in the complex network of cancer and play vital roles as oncogenes or tumor-suppressor genes in a variety of cancers. Moreover, recent research has shown that abnormal expression of lncRNAs in malignant tumor cells before and after radiotherapy may participate in the progression of cancers and affect the radiation sensitivity of malignant tumor cells mediated by specific signaling pathways or cell cycle regulation. In this review, we summarize the published studies on lncRNAs in radiotherapy regarding the biological function and mechanism of human cancers, including esophageal cancer, pancreatic cancers, nasopharyngeal carcinoma, hepatocellular carcinoma, cervical cancer, colorectal cancer, and gastric cancer.

The long noncoding RNA CTA-941F9.9 is frequently downregulated and may serve as a biomarker for carcinogenesis in colorectal cancer

BACKGROUND

Long noncoding RNAs (lncRNAs) participate in the carcinogenesis of many different cancers. This study aimed to detect expression of lncRNA CTA-941F9.9 in colorectal cancer tissues compared with matched nontumorous adjacent tissues (NATs). Moreover, we investigated whether this molecule is able to influence carcinogenesis in colorectal cancer (CRC).

METHODS

Colorectal cancer tissues and NATs from two cohorts of patients were examined. Quantitative PCR was performed to quantify levels of CTA-941F9.9 expression in these samples. The association between CTA-941F9.9 expression and clinicopathological features, including receiver operating characteristic (ROC) curves, was also analyzed to evaluate the diagnostic value of CTA-941F9.9 in CRC. Potential effects of lncRNA CTA-941F9.9 on CRC cells were assessed via autophagy, transwell assay, CCK8 assays, and flow cytometry.

RESULTS

Our experimental results showed lncRNA CTA-941F9.9 to be significantly downregulated in CRC tissues in both cohorts, with areas under the ROC curve (AUC) of 0.802 and 0.876. However, no significant correlations between CTA-941F9.9 expression levels and clinicopathological characteristics or patient outcomes were observed. We also found that CTA-941F9.9 promotes autophagy in CRC cell lines but no significant function of CTA-941F9.9 in regulating cancer cell proliferation or migration.

CONCLUSIONS

LncRNA CTA-941F9.9 is frequently downregulated in CRC compared with NATs and might play an important role in CRC carcinogenesis.

Functional polymorphisms in LncRNA HOTAIR contribute to susceptibility of pancreatic cancer

Background

Pancreatic cancer (PC) remains one of the most aggressive cancers worldwide. However, genetic factors underlying PC susceptibility remain largely unclear. Long noncoding RNA (lncRNA) HOX transcript antisense RNA (HOTAIR) acts as an oncogene and its genetic variation has been linked to many cancers. However, the associations between genetic variants in HOTAIR gene and PC risk has not yet been reported.

Methods

A two-stage, case–control study was conducted to investigate the associations between HOTAIR SNPs and the PC risk. Dual luciferase reporter assay and real-time -PCR (RT-PCR) was conducted to evaluate the potential regulatory function of HOTAIR rs4759314 and rs200349340.

Results

We found the minor alleles of rs4759314 (OR = 1.76; 95 CI 1.37–2.25; P = 0.001) and rs200349340 (OR = 1.32; 95 CI 1.12–1.56; P = 0.001) were significantly associated with PC susceptibility. In functional experiments, we found subjects carrying the minor alleles of rs4759314 and rs200349340 had significantly higher HOTAIR RNA levels (mean ± SD) than those carrying the major alleles in PC tissues. For rs4759314, cells transfected with rs4759314 -G allele construct showed higher relative luciferase activity; while for rs200349340, cells transfected with rs200349340 -G allele construct showed more sensitive change of the relative luciferase activity.

Conclusion

Our studies revealed that functional SNP rs4759314 and rs200349340 of HOTAIR had strong associations with PC susceptibility. These findings elucidate that functional genetic variants influencing lncRNA expression may explain a portion of PC genetic basis.

Electronic supplementary material

The online version of this article (10.1186/s12935-019-0761-x) contains supplementary material, which is available to authorized users.

The therapeutic role of long non-coding RNAs in human diseases: A focus on the recent insights into autophagy

Long non-coding RNA (lncRNA) is a class of non-coding RNA with ≥200 nucleotides in length which are involved as critical regulators in various cellular processes. LncRNAs contribute to the development and progression of many human diseases. Autophagy is a key catabolic process which helps to maintain the cellular homeostasis through the decay of damaged or unwanted proteins and dysfunctional cytoplasmic organelles. The impairment of the autophagy process has been described in numerous diseases. The autophagy possess can have either a protective or a detrimental role in cells depending on its activation status and other cellular conditions. LncRNAs have been shown to have an important function in the regulation of important biological processes such as autophagy. The relationship between lncRNAs and autophagy has been shown to be involved in the progression and possibly in the prevention of many diseases. In this review, recent findings on the regulatory roles of lncRNAs in the cell autophagy pathway, as well as their relevance to different diseases such as cardiovascular disease, cerebral ischemic stroke and cancer are highlighted.

Effects of minocycline and rapamycin in gamma-irradiated human embryonic stem cells-derived cerebral organoids

Radiation induces DNA and protein damage and free radical formation, effectively establishing cellular senescence in a variety of models. We demonstrate the effects of two known pleiotropic drugs following gamma radiation damage in neurosphere/cerebral organoid system based on human embryonic stem cells. mTORC1 repression by rapamycin prior to irradiation, or metabolic activation by minocycline after irradiation, partially rescues neuroepithelium integrity, neurite-growing capacity, ventricle formation and extracellular acidification rate as an integral measure of metabolic output. Cerebral organoid model thus provides valid and robust readouts for radiation studies in a complex 3D setting.