The crosstalk between long non-coding RNAs and PI3K in cancer. Med Oncol. 2017;34:39. [PMID: 28176240 DOI: 10.1007/s12032-017-0897-2]

MicroRNA-409: Molecular functions and clinical applications in cancer

Late diagnosis is one of the main reasons for high mortality rates in cancer patients. Therefore, investigating the molecular mechanisms involved in tumor progression can improve the cancer diagnosis in the early stages of the tumor progression. MicroRNAs (miRNAs) have important roles in regulation of cell growth, proliferation, metabolism, and migration. Since, deregulation of miR-409 has been reported in a wide range of cancers, in the present review, we investigated the molecular mechanisms of miR-409 during tumor progression and invasion. It has been shown that miR-409 functions as a tumor suppressor in different tumor types. MiR-409 can reduce tumor cell proliferation, growth, and migration by regulation of signaling pathways, cellular metabolism, transcription factors, and cellular adhesion. This review can be an effective step in introducing miR-409 as a non-invasive marker in cancer patients.

Function of Long Noncoding RNAs in Glioma Progression and Treatment Based on the Wnt/β-Catenin and PI3K/AKT Signaling Pathways

Gliomas are a deadly primary malignant tumor of the central nervous system, with glioblastoma (GBM) representing the most aggressive type. The clinical prognosis of GBM patients remains bleak despite the availability of multiple options for therapy, which has needed us to explore new therapeutic methods to face the rapid progression, short survival, and therapy resistance of glioblastomas. As the Human Genome Project advances, long noncoding RNAs (lncRNAs) have attracted the attention of researchers and clinicians in cancer research. Numerous studies have found aberrant expression of signaling pathways in glioma cells. For example, lncRNAs not only play an integral role in the drug resistance process by regulating the Wnt/β-catenin or PI3K/Akt signaling but are also involved in a variety of malignant biological behaviors such as glioma proliferation, migration, invasion, and tumor apoptosis. Therefore, the present review systematically assesses the existing research evidence on the malignant progression and drug resistance of glioma, focusing on the critical role and potential function of lncRNAs in the Wnt/β-catenin and PI3K/Akt classical pathways to promote and encourage further research in this field.

Imprinted Dlk1-Gtl2 cluster miRNAs are potential epigenetic regulators of lamb fur quality

BACKGROUND

Tan and Hu sheep are well-known local breeds in China, producing lamb fur with unique ornamental and practical values highly appreciated by consumers worldwide. Fur quality is optimal at one month of age and gradually declines with time. Despite active research on its genetic mechanism using transcriptomic and whole genome bisulfite sequencing analysis, the main effective gene locus has not been found, and its regulatory mechanism is still unclear, which limits the breeding and improvement of fur traits.

RESULTS

Scapular skin samples from newborn (1-month old) and adult (24-month old) Tan sheep were utilized for small ribonucleic acid (RNA) sequencing Principal Component Analysis (PCA) showed that the newborn and adult groups were completely separated. Differential expression analysis of micro-RNAs (miRNAs) identified 32 up-regulated miRNAs and 48 down-regulated miRNAs in the newborn groups. All up-regulated miRNAs were located in the imprinted. Dlk1-Gtl2 locus on chromosome 18, whereas all down-regulated miRNAs were distributed across the sheep chromosomes, without a clear pattern of positional consistency. Further, by systematically analyzing the target genes and signaling pathways of all 32 up-regulated miRNAs, we found that the PI3K-AKT signaling pathway has the potential to be targeted and regulated by most of the miRNAs in the Dlk1-Gtl2 region. In addition, we also re-analyzed miRNA sequencing data from public databases on Hu lambs (full sibling Hu lambs with high- and low-quality fur characteristics). Again, it was found that most of the up-regulated miRNAs in lambs with high-quality fur were also located in the Dlk1-Gtl2 region, whereas this patter was not present for down-regulated miRNAs.

CONCLUSION

Sequencing of miRNAs in conjunction with public databases was employed to identify miRNAs within the imprinted Dlk1-Gtl2 region on chromosome 18, suggesting their potential roles as epigenetic regulators of fur traits. Small RNAs located at the Dlk1-Gtl2 locus were identified as having the potential to systematically regulate the PI3K-AKT signaling pathway, thereby indicating the relevance of the Dlk1-Gtl2/PI3K-AKT axis in the context of fur traits. Selection of parental specific expressed imprinted genes in the process of conserving and exploiting lamb fur traits should be emphasized.

Maternal Kdm2a-mediated PI3K/Akt signaling and E-cadherin stimulate the morula-to-blastocyst transition revealing crucial roles in early embryonic development

Histone methylation plays an essential role in oocyte growth and preimplantation embryonic development. The modification relies on histone methyl-transferases and demethylases, and one of these, lysine-specific demethylase 2a (Kdm2a), is responsible for modulating histone methylation during oocyte and early embryonic development. The mechanism of how Kdm2a deficiency disrupts early embryonic development and fertility remains elusive. To determine if maternally deposited Kdm2a is required for preimplantation embryonic development, the expression profile of Kdm2a during early embryos was detected via immunofluorescence staining and RT-qPCR. The Kdm2a gene in oocytes was specifically deleted with the Zp3-Cre/LoxP system and the effects of maternal Kdm2a loss were studied through a comprehensive range of female reproductive parameters including fertilization, embryo development, and the number of births. RNA transcriptome sequencing was performed to determine differential mRNA expression, and the interaction between Kdm2a and the PI3K/Akt pathway was studied with a specific inhibitor and activator. Our results revealed that Kdm2a was continuously expressed in preimplantation embryos and loss of maternal Kdm2a suppressed the morula-to-blastocyst transition, which may have been responsible for female subfertility. After the deletion of Kdm2a, the global H3K36me2 methylation in mutant embryos was markedly increased, but the expression of E-cadherin decreased significantly in morula embryos compared to controls. Mechanistically, RNA-seq analysis revealed that deficiency of maternal Kdm2a altered the mRNA expression profile, especially in the PI3K/Akt signaling pathway. Interestingly, the addition of a PI3K/Akt inhibitor (LY294002) to the culture medium blocked embryo development at the stage of morula; however, the developmental block caused by maternal Kdm2a loss was partially rescued with a PI3K/Akt activator (SC79). In summary, our results indicate that loss of Kdm2a influences the transcriptome profile and disrupts the PI3K/Akt signaling pathway during the development of preimplantation embryo. This can result in embryo block at the morula stage and female subfertility, which suggests that maternal Kdm2a is a potential partial redundancy with other genes encoding enzymes in the dynamics of early embryonic development. Our results provide further insight into the role of histone modification, especially on Kdm2a, in preimplantation embryonic development in mice.

Pathogenesis and Current Treatment Strategies of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the most frequent liver cancer with high lethality and low five-year survival rates leading to a substantial worldwide burden for healthcare systems. HCC initiation and progression are favored by different etiological risk factors including hepatitis B virus (HBV) and hepatitis C virus (HCV) infection, non-/and alcoholic fatty liver disease (N/AFLD), and tobacco smoking. In molecular pathogenesis, endogenous alteration in genetics (TP53, TERT, CTNNB1, etc.), epigenetics (DNA-methylation, miRNA, lncRNA, etc.), and dysregulation of key signaling pathways (Wnt/β-catenin, JAK/STAT, etc.) strongly contribute to the development of HCC. The multitude and complexity of different pathomechanisms also reflect the difficulties in tailored medical therapy of HCC. Treatment options for HCC are strictly dependent on tumor staging and liver function, which are structured by the updated Barcelona Clinic Liver Cancer classification system. Surgical resection, local ablative techniques, and liver transplantation are valid and curative therapeutic options for early tumor stages. For multifocal and metastatic diseases, systemic therapy is recommended. While Sorafenib had been the standalone HCC first-line therapy for decades, recent developments had led to the approval of new treatment options as first-line as well as second-line treatment. Anti-PD-L1 directed combination therapies either with anti-VEGF directed agents or with anti-CTLA-4 active substances have been implemented as the new treatment standard in the first-line setting. However, data from clinical trials indicate different responses on specific therapeutic regimens depending on the underlying pathogenesis of hepatocellular cancer. Therefore, histopathological examinations have been re-emphasized by current international clinical guidelines in addition to the standardized radiological diagnosis using contrast-enhanced cross-sectional imaging. In this review, we emphasize the current knowledge on molecular pathogenesis of hepatocellular carcinoma. On this occasion, the treatment sequences for early and advanced tumor stages according to the recently updated Barcelona Clinic Liver Cancer classification system and the current algorithm of systemic therapy (first-, second-, and third-line treatment) are summarized. Furthermore, we discuss novel precautional and pre-therapeutic approaches including therapeutic vaccination, adoptive cell transfer, locoregional therapy enhancement, and non-coding RNA-based therapy as promising treatment options. These novel treatments may prolong overall survival rates in regard with quality of life and liver function as mainstay of HCC therapy.

Aspirin sensitivity of PIK3CA-mutated Colorectal Cancer: potential mechanisms revisited

PIK3CA mutations are amongst the most prevalent somatic mutations in cancer and are associated with resistance to first-line treatment along with low survival rates in a variety of malignancies. There is evidence that patients carrying PIK3CA mutations may benefit from treatment with acetylsalicylic acid, commonly known as aspirin, particularly in the setting of colorectal cancer. In this regard, it has been clarified that Class IA Phosphatidylinositol 3-kinases (PI3K), whose catalytic subunit p110α is encoded by the PIK3CA gene, are involved in signal transduction that regulates cell cycle, cell growth, and metabolism and, if disturbed, induces carcinogenic effects. Although PI3K is associated with pro-inflammatory cyclooxygenase-2 (COX-2) expression and signaling, and COX-2 is among the best-studied targets of aspirin, the mechanisms behind this clinically relevant phenomenon are still unclear. Indeed, there is further evidence that the protective, anti-carcinogenic effect of aspirin in this setting may be mediated in a COX-independent manner. However, until now the understanding of aspirin's prostaglandin-independent mode of action is poor. This review will provide an overview of the current literature on this topic and aims to analyze possible mechanisms and targets behind the aspirin sensitivity of PIK3CA-mutated cancers.

LncRNA DLEU2 silencing impedes the migration, invasion and EMT in gastric cancer cell by suppressing PI3K/AKT signaling pathway

Context: The high expression of long non-coding RNA deleted in lymphocytic leukaemia 2 (lncRNA DLEU2) has been confirmed in gastric cancer (GC).Objective: However, the detailed mechanism concerning its involvement in GC remained unclear, which we aimed to explore in this study.Materials and methods: LncRNA DLEU2 expression in GC was estimated by bioinformatic analysis, and the relationship between the expression of DLEU2 and the clinicopathological characteristics of patients with GC was performed. qRT-PCR was employed to detect the expression of lncRNA DLEU2 and confirm the transfection efficiency following the knockdown or overexpression of DLEU2. Functional assays, including CCK-8, flow cytometry, scratching test and Transwell assays, were used to determine the role of DLEU2 in tumor phenotypes. The effects of DLEU2 on the PI3K/Akt pathway were detected by western blot. For elucidating the functions of DLEU2/PI3K/Akt axis in GC, we inhibited the PI3K/Akt pathway in rescue experiments, and evaluated the expression levels of epithelial-mesenchymal transition (EMT)-related proteins by western blot.Results: The expression of DLEU2 was aberrantly up-regulated in GC tissues and cells, which was correlated with the degree of tumor differentiation, cancer antigen 19-9 (CA19-9) and Lauren histologic classification of patients with GC. Silencing of DLEU2 induced apoptosis, attenuated viability, migration and invasion as well as inhibited the PI3K/Akt signaling pathway in GC cells. Mechanistically, the DLEU2/PI3K/Akt axis promoted the progression of GC and the EMT by down-regulating the expression of E-Cadherin and up-regulating those of N-Cadherin and Vimentin.Discussion and conclusions: LncRNA DLEU2 promoted the migration, invasion and EMT in GC by activating the PI3K/Akt pathway.

The structure-based cancer-related single amino acid variation prediction

Single amino acid variation (SAV) is an amino acid substitution of the protein sequence that can potentially influence the entire protein structure or function, as well as its binding affinity. Protein destabilization is related to diseases, including several cancers, although using traditional experiments to clarify the relationship between SAVs and cancer uses much time and resources. Some SAV prediction methods use computational approaches, with most predicting SAV-induced changes in protein stability. In this investigation, all SAV characteristics generated from protein sequences, structures and the microenvironment were converted into feature vectors and fed into an integrated predicting system using a support vector machine and genetic algorithm. Critical features were used to estimate the relationship between their properties and cancers caused by SAVs. We describe how we developed a prediction system based on protein sequences and structure that is capable of distinguishing if the SAV is related to cancer or not. The five-fold cross-validation performance of our system is 89.73% for the accuracy, 0.74 for the Matthews correlation coefficient, and 0.81 for the F1 score. We have built an online prediction server, CanSavPre ( http://bioinfo.cmu.edu.tw/CanSavPre/ ), which is expected to become a useful, practical tool for cancer research and precision medicine.

Signaling pathways in cancer-associated fibroblasts and targeted therapy for cancer

To flourish, cancers greatly depend on their surrounding tumor microenvironment (TME), and cancer-associated fibroblasts (CAFs) in TME are critical for cancer occurrence and progression because of their versatile roles in extracellular matrix remodeling, maintenance of stemness, blood vessel formation, modulation of tumor metabolism, immune response, and promotion of cancer cell proliferation, migration, invasion, and therapeutic resistance. CAFs are highly heterogeneous stromal cells and their crosstalk with cancer cells is mediated by a complex and intricate signaling network consisting of transforming growth factor-beta, phosphoinositide 3-kinase/AKT/mammalian target of rapamycin, mitogen-activated protein kinase, Wnt, Janus kinase/signal transducers and activators of transcription, epidermal growth factor receptor, Hippo, and nuclear factor kappa-light-chain-enhancer of activated B cells, etc., signaling pathways. These signals in CAFs exhibit their own special characteristics during the cancer progression and have the potential to be targeted for anticancer therapy. Therefore, a comprehensive understanding of these signaling cascades in interactions between cancer cells and CAFs is necessary to fully realize the pivotal roles of CAFs in cancers. Herein, in this review, we will summarize the enormous amounts of findings on the signals mediating crosstalk of CAFs with cancer cells and its related targets or trials. Further, we hypothesize three potential targeting strategies, including, namely, epithelial-mesenchymal common targets, sequential target perturbation, and crosstalk-directed signaling targets, paving the way for CAF-directed or host cell-directed antitumor therapy.

Cross-talk between non-coding RNAs and PI3K/AKT/mTOR pathway in colorectal cancer

Colorectal cancer (CRC) is the third commonest cancer globally, with metastasis being the reason for cancer-associated mortality. Much is still unknown biochemically about CRC, and with current treatments that are not wholly effective over time, new therapeutics are urgently needed. Emerging evidence has shown the importance of non-coding RNAs such as lncRNAs and miRNAs functions in the development and progression of CRC. However, the exact underlying mechanism of these types of RNAs in CRC is still mostly unknown. PI3K/AKT/mTOR pathway contributes to many cellular processes, and dysregulation of this pathway frequently occurs in cancers. In this review, the authors have mostly focused on the significant non-coding RNAs regulators of the PI3K/AKT/mTOR pathway and their contribution to the development or inhibition of CRC and their potential as diagnostic or therapeutic targets in CRC treatment.

PI3K/AKT/mTOR pathway-related long non-coding RNAs: roles and mechanisms in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common tumors worldwide with high prevalence and lethality. The oncogenic phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) pathway is a classic dysregulated pathway involved in the pathogenesis of HCC. However, the underlying mechanism for how PI3K/AKT/mTOR pathway aberrantly activates HCC has not been entirely elucidated. The recognition of the functional roles of long non-coding RNAs (lncRNAs) in PI3K/AKT/mTOR signaling axis sheds light on a new dimension to our understanding of hepatocarcinogenesis. In this review, we comprehensively summarize 67 dysregulated PI3K/AKT/mTOR pathway-related lncRNAs in HCC. Many studies have indicated that the 67 dysregulated lncRNAs show oncogenic or anti-oncogenic effects in HCC by regulation on epigenetic, transcriptional and post-transcriptional levels and they play pivotal roles in the initiation of HCC in diverse biological processes like proliferation, metastasis, drug resistance, radio-resistance, energy metabolism, autophagy and so on. Besides, many of these lncRNAs are associated with clinicopathological features and clinical prognosis in HCC, which may provide a potential future application in the diagnosis and therapy of HCC.

Long Non-Coding RNA DUXAP8 Facilitates Cell Viability, Migration, and Glycolysis in Non-Small-Cell Lung Cancer via Regulating HK2 and LDHA by Inhibition of miR-409-3p

Purpose

Long non-coding RNAs (lncRNAs) were confirmed to play important roles in human cancers. In this study, we explored the functional role of lncRNA double homeobox A pseudogene 8 (DUXAP8) in non-small-cell lung cancer (NSCLC).

Methods

Real-time quantitative PCR (RT-qPCR) was used to detect DUXAP8 and microRNA-409-3p (miR-409-3p) expression. CCK-8, cell colony formation assay, and Transwell migration assay were performed to measure cell growth and migration, respectively. The expression of the relative proteins was detected by Western blot. Cell glycolysis was determined by glucose uptake, adenosine triphosphate (ATP) concentration, lactate generation, extracellular acidification rate and oxygen consumption rate assays. Bioinformatics analysis and dual-luciferase reporter assay were used to measure the interaction among DUXAP8, miR-409-3p, hexokinase 2 (HK2) and lactate dehydrogenase A (LDHA). In vivo, subcutaneous tumor formation assay was performed in the nude mice.

Results

DUXAP8 was highly expressed in NSCLC, while miR-409-3p was downregulated. High expression of DUXAP8 was positively related to the grade division and negatively associated with the 5-year survival rate of NSCLC patients. Downregulated DUXAP8 significantly suppressed cell growth, metastasis and glycolysis. Besides, DUXAP8 sponged miR-409-3p to promote HK2 and LDHA expression. DUXAP8 promoted cell viability, migration and glycolysis by regulating miR-409-3p/HK2/LDHA axis. Moreover, DUXAP8 downregulation markedly inhibited tumor growth in vivo.

Conclusion

Our findings demonstrated that DUXAP8 served as an oncogene in the progression of NSCLC.

Long non-coding RNAs and MYC association in hematological malignancies

Long non-coding RNAs (lncRNAs) have an established role in cell biology. Among their functions is the regulation of hematopoiesis. They characterize the different stages of hematopoiesis in a more lineage-restricted expression pattern than coding mRNAs. They affect hematopoietic stem cell renewal, proliferation, and differentiation of committed progenitors by interacting with master regulators transcription factors. Among these transcription factors, MYC has a prominent role. Similar to MYC's transcriptional activation/amplification of protein coding genes, MYC also regulates lncRNAs' expression profile, while it is also regulated by lncRNAs. Both myeloid and lymphoid malignancies are prone to the association of MYC with lncRNAs. Such interaction inhibits apoptosis, enhances cell proliferation, deregulates metabolism, and promotes genomic instability and resistance to treatment. In this review, we discuss the recent findings that encompass the crosstalk between lncRNAs and describe the pathways that very probably have a pathogenetic role in both acute and chronic hematologic malignancies.

Linc00423 as a tumor suppressor in retroperitoneal liposarcoma via activing MAPK signaling pathway through destabilizing of NFATC3

Unraveling the noncoding RNA expression networks governing cancer initiation and development is essential while remains largely uncompleted in retroperitoneal liposarcoma (RLS). Through RNA-seq technologies and computational biology, deregulated long noncoding RNAs (lncRNAs) are being identified and reveal that lncRNAs are implicated in serial steps of RLS development. High-throughput sequencing with computational methods for assembling the transcriptome of five paired RLS patient’s tissues. We found that long intergenic noncoding RNA 423 (linc00423) was downregulated in RLS tissues. Gain-of-function assays revealed that overexpressed linc00423 obviously inhibited RLS cell growth in vitro and in vivo. Additionally, RNA sequence, RNA-pulldown and RIP assays evidenced that linc00423 involved in MAPK signaling pathway via destabilizing of nuclear factor of activated T-cells 3 (NFATC3). Summing up, our findings demonstrated that linc00423 acted as the tumor suppressor in RLS cells through regulating the protein level of NFATC3 at a post-transcriptional level and negatively regulated the MAPK signaling pathway at a transcriptional level. Linc00423 might serve as a candidate prognostic biomarker and a target for novel therapies of RLS patients.

Targeting PI3K in cancer: mechanisms and advances in clinical trials

Phosphatidylinositol-3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) signaling is one of the most important intracellular pathways, which can be considered as a master regulator for cancer. Enormous efforts have been dedicated to the development of drugs targeting PI3K signaling, many of which are currently employed in clinical trials evaluation, and it is becoming increasingly clear that PI3K inhibitors are effective in inhibiting tumor progression. PI3K inhibitors are subdivided into dual PI3K/mTOR inhibitors, pan-PI3K inhibitors and isoform-specific inhibitors. In this review, we performed a critical review to summarize the role of the PI3K pathway in tumor development, recent PI3K inhibitors development based on clinical trials, and the mechanisms of resistance to PI3K inhibition.

Long Noncoding RNA Taurine-Upregulated Gene1 (TUG1) Promotes Tumor Growth and Metastasis Through TUG1/Mir-129-5p/Astrocyte-Elevated Gene-1 (AEG-1) Axis in Malignant Melanoma

BACKGROUND Malignant melanoma is a class of malignant tumors derived from melanocytes. lncRNAs have been considered as pro-/anti-tumor factors in progression of cancers. The function of lncRNA TUG1 on growth of melanoma was investigated in this study. MATERIAL AND METHODS The TUG1 and miR-129-5p expression were examined via qRT-PCR. The protein expression was investigated by Western blotting assay. Luciferase reporter assay was used to assess if lncRNA TUG1 can bind to miR-129-5p and if miR-129-5p can target AEG1 mRNA. CCK-8 and apoptosis assay were used to detect cell growth and apoptosis. The metastasis of melanoma cells was detected by wound-healing and Transwell assays. The effects of TUG1 on growth of melanoma in vivo and cell chemoresistance were investigated via xenograft animal experiment and CCK-8 assay. RESULTS The expression of TUG1 and AEG1 was elevated and the miR-129-5p level was decreased in melanoma specimens and cell lines. Downregulation of either TUG1 or AEG1 suppressed cell growth and metastasis. miR-129-5p can bind directly to AEG1 and TUG1 can directly sponge miR-129-5p. Inhibition of TUG1 expression suppressed the expression of Bcl-2, MMP-9, and cyclin D1, and raised the level of cleaved caspase3 by modulating AEG1 level in melanoma cells. Inhibition of TUG1 reduced the growth of tumors in vivo and improved the chemosensitivity of A375 cells to cisplatin and 5-FU. CONCLUSIONS Reduction of TUG1 level suppressed cell growth and metastasis by regulating AEG1 expression mediated by targeting miR-129-5p. Suppression of lnc TUG1 may be a promising therapeutic strategy in the treatment of malignant melanoma.

Drosophila as a Model to Gain Insight into the Role of lncRNAs in Neurological Disorders

It is now clear that the majority of transcription in humans results in the production of long non-protein-coding RNAs (lncRNAs) with a variable length spanning from 200 bp up to several kilobases. To date, we have a limited understanding of the lncRNA function, but a huge number of evidences have suggested that lncRNAs represent an outstanding asset for cells. In particular, temporal and spatial expression of lncRNAs appears to be important for proper neurological functioning. Stunningly, abnormal lncRNA function has been found as being critical for the onset of neurological disorders. This chapter focus on the lncRNAs with a role in diseases affecting the central nervous system with particular regard for the lncRNAs causing those neurodegenerative diseases that exhibit dementia and/or motor dysfunctions. A specific section will be dedicated to the human neuronal lncRNAs that have been modelled in Drosophila. Finally, even if only few examples have been reported so far, an overview of the Drosophila lncRNAs with neurological functions will be also included in this chapter.

Long non-coding RNAs in hepatocellular carcinoma: Potential roles and clinical implications

Long non-coding RNAs (lncRNAs) are a subgroup of non-coding RNA transcripts greater than 200 nucleotides in length with little or no protein-coding potential. Emerging evidence indicates that lncRNAs may play important regulatory roles in the pathogenesis and progression of human cancers, including hepatocellular carcinoma (HCC). Certain lncRNAs may be used as diagnostic or prognostic markers for HCC, a serious malignancy with increasing morbidity and high mortality rates worldwide. Therefore, elucidating the functional roles of lncRNAs in tumors can contribute to a better understanding of the molecular mechanisms of HCC and may help in developing novel therapeutic targets. In this review, we summarize the recent progress regarding the functional roles of lncRNAs in HCC and explore their clinical implications as diagnostic or prognostic biomarkers and molecular therapeutic targets for HCC.