Non-coding RNAs, the Trojan horse in two-way communication between tumor and stroma in colorectal and hepatocellular carcinoma

A first comprehensive analysis of Transcribed Ultra Conserved Regions uncovers important regulatory functions of novel non-coding transcripts in gliomas

Transcribed Ultra-Conserved Regions (TUCRs) represent a severely understudied class of putative non-coding RNAs (ncRNAs) that are 100% conserved across multiple species. We performed the first-ever analysis of TUCRs in glioblastoma (GBM) and low-grade gliomas (LGG). We leveraged large human datasets to identify the genomic locations, chromatin accessibility, transcription, differential expression, correlation with survival, and predicted functions of all 481 TUCRs, and identified TUCRs that are relevant to glioma biology. Of these, we investigated the expression, function, and mechanism of action of the most highly upregulated intergenic TUCR, uc.110, identifying it as a new oncogene. Uc.110 was highly overexpressed in GBM and LGG, where it promoted malignancy and tumor growth. Uc.110 activated the WNT pathway by upregulating the expression of membrane frizzled-related protein (MFRP), by sponging the tumor suppressor microRNA miR-544. This pioneering study shows important roles for TUCRs in gliomas and provides an extensive database and novel methods for future TUCR research.

Novel insights on perils and promises of miRNA in understanding colon cancer metastasis and progression

Colorectal cancer (CRC) is the third highest frequent malignancy and ultimate critical source of cancer-associated mortality around the world. Regardless of latest advances in molecular and surgical targeted medicines that have increased remedial effects in CRC patients, the 5-year mortality rate for CRC patients remains dismally low. Evidence suggests that microRNAs (miRNAs) execute an essential part in the development and spread of CRC. The miRNAs are a type of short non-coding RNA that exhibited to control the appearance of tumor suppressor genes and oncogenes. miRNA expression profiling is already being utilized in clinical practice as analytical and prognostic biomarkers to evaluate cancer patients' tumor genesis, advancement, and counteraction to drugs. By modulating their target genes, dysregulated miRNAs are linked to malignant characteristics (e.g., improved proliferative and invasive capabilities, cell cycle aberration, evasion of apoptosis, and promotion of angiogenesis). This review presents an updated summary of circulatory miRNAs, tumor-suppressive and oncogenic miRNAs, and the potential reasons for dysregulated miRNAs in CRC. Further we will explore the critical role of miRNAs in CRC drug resistance.

Role of non‑coding RNAs in cartilage endplate (Review)

Cartilage endplate (CEP) degeneration is considered one of the major causes of intervertebral disc degeneration (IDD), which causes non-specific neck and lower back pain. In addition, several non-coding RNAs (ncRNAs), including long ncRNAs, microRNAs and circular RNAs have been shown to be involved in the regulation of various diseases. However, the particular role of ncRNAs in CEP remains unclear. Identifying these ncRNAs and their interactions may prove to be is useful for the understanding of CEP health and disease. These RNA molecules regulate signaling pathways and biological processes that are critical for a healthy CEP. When dysregulated, they can contribute to the development disease. Herein, studies related to ncRNAs interactions and regulatory functions in CEP are reviewed. In addition, a summary of the current knowledge regarding the deregulation of ncRNAs in IDD in relation to their actions on CEP cell functions, including cell proliferation, apoptosis and extracellular matrix synthesis/degradation is presented. The present review provides novel insight into the pathogenesis of IDD and may shed light on future therapeutic approaches.

Exploratory Evaluation of Neopterin and Chitotriosidase as Potential Circulating Biomarkers for Colorectal Cancer

Chronic inflammation is demonstrated to play a direct role in carcinogenesis. Our exploratory study aimed to assess the potential added value of two inflammation biomarkers, chitotriosidase and neopterin, in follow-up evaluation of patients with colorectal cancer (CRC). An observational exploratory study was conducted. Patients with CRC and matched controls (1:1, age, sex, and living environment) were evaluated. The patients with CRC (CRC group) and controls were assessed at baseline (before surgical intervention for patients with CRC). Patients with CRC were also evaluated at 1-year follow-up. Significantly more patients with blood group A (54.5% vs. 25.0%) and smokers (50.0% vs. 22.7%) were in the CRC group. The serum values of chitotriosidase and neopterin were higher in CRC patients than in controls, but only neopterin reached the conventional level of statistical significance (p-value = 0.015). The circulating chitotriosidase and neopterin values decreased significantly at 1-year follow-up (p-value < 0.0001). Patients with higher N- and M-stage showed statistically significant higher levels of chitotriosidase and neopterin at baseline and 1-year follow-up (p-values < 0.03). Circulating chitotriosidase levels also showed statistically significant differences regarding baseline and 1-year follow-up on patients with CRC and different differentiation grades (p-values < 0.02). The circulating levels of neopterin significantly decreased at 1-year follow-up, indicating its potential as a prognostic marker. The circulating values of chitotriosidase and neopterin exhibit significant differences in patients with than without recurrences. Our results support further evaluation of chitotriosidase and neopterin as prognostic markers in patients with CRC.

Targeting lncRNAs of colorectal cancers with natural products

Non-coding RNA (ncRNA) is one of the functional classes of RNA that has a regulatory role in various cellular processes, such as modulation of disease onset, progression, and prognosis. ncRNAs, such as microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), have been actively studied in recent years. The change in ncRNA levels is being actively studied in numerous human diseases, especially auto-immune disorders and cancers; however, targeting and regulating ncRNA with natural products to cure cancer has not been fully established. Recently many groups reported the relationship between ncRNA and natural products showing promising effects to serve as additional therapeutic approaches to cure cancers. This mini-review summarizes the aspects of lncRNAs related to cancer biology focusing on colorectal cancers that natural products can target.

Transcribed Ultraconserved Regions in Cancer

Transcribed ultraconserved regions are putative lncRNA molecules that are transcribed from DNA that is 100% conserved in human, mouse, and rat genomes. This is notable, as lncRNAs are typically poorly conserved. TUCRs remain very understudied in many diseases, including cancer. In this review, we summarize the current literature on TUCRs in cancer with respect to expression deregulation, functional roles, mechanisms of action, and clinical perspectives.

Biological Implications and Clinical Potential of Metastasis-Related miRNA in Colorectal Cancer

Colorectal cancer (CRC), ranking as the third commonest cancer, leads to extremely high rates of mortality. Metastasis is the major cause of poor outcome in CRC. When metastasis occurs, 5-year survival rates of patients decrease sharply, and strategies to enhance a patient's lifetime seem limited. MicroRNAs (miRNAs) are evolutionarily conserved small non-coding RNAs that are significantly involved in manipulation of CRC malignant phenotypes, including proliferation, invasion, and metastasis. To date, accumulating studies have revealed the mechanisms and functions of certain miRNAs in CRC metastasis. However, there is no systematic discussion about the biological implications and clinical potential (diagnostic role, prognostic role, and targeted therapy potential) of metastasis-related miRNAs in CRC. This review mainly summarizes the recent advances of miRNA-mediated metastasis in CRC. We also discuss the clinical values of metastasis-related miRNAs as potential biomarkers or therapeutic targets in CRC. Moreover, we envisage the future orientation and challenges in translating these findings into clinical applications.

Polyphenols as Caloric-Restriction Mimetics and Autophagy Inducers in Aging Research

It has been thought that caloric restriction favors longevity and healthy aging where autophagy plays a vital role. However, autophagy decreases during aging and that can lead to the development of aging-associated diseases such as cancer, diabetes, neurodegeneration, etc. It was shown that autophagy can be induced by mechanical or chemical stress. In this regard, various pharmacological compounds were proposed, including natural polyphenols. Apart from the ability to induce autophagy, polyphenols, such as resveratrol, are capable of modulating the expression of pro- and anti-apoptotic factors, neutralizing free radical species, affecting mitochondrial functions, chelating redox-active transition metal ions, and preventing protein aggregation. Moreover, polyphenols have advantages compared to chemical inducers of autophagy due to their intrinsic natural bio-compatibility and safety. In this context, polyphenols can be considered as a potential therapeutic tool for healthy aging either as a part of a diet or as separate compounds (supplements). This review discusses the epigenetic aspect and the underlying molecular mechanism of polyphenols as an anti-aging remedy. In addition, the recent advances of studies on NAD-dependent deacetylase sirtuin-1 (SIRT1) regulation of autophagy, the role of senescence-associated secretory phenotype (SASP) in cells senescence and their regulation by polyphenols have been highlighted as well. Apart from that, the review also revised the latest information on how polyphenols can help to improve mitochondrial function and modulate apoptosis (programmed cell death).

Implications of Long Non-Coding RNAs in Age-Altered Proteostasis

This review aims to summarize the current knowledge on how lncRNAs are influencing aging and cancer metabolism. Recent research has shown that senescent cells re-enter cell-cycle depending on intrinsic or extrinsic factors, thus restoring tissue homeostasis in response to age-related diseases (ARDs). Furthermore, maintaining proteostasis or cellular protein homeostasis requires a correct quality control (QC) of protein synthesis, folding, conformational stability, and degradation. Long non-coding RNAs (lncRNAs), transcripts longer than 200 nucleotides, regulate gene expression through RNA-binding protein (RBP) interaction. Their association is linked to aging, an event of proteostasis collapse. The current review examines approaches that lead to recognition of senescence-associated lncRNAs, current methodologies, potential challenges that arise from studying these molecules, and their crucial implications in clinical practice.

An Emerging Class of Long Non-coding RNA With Oncogenic Role Arises From the snoRNA Host Genes

The small nucleolar RNA host genes (SNHGs) are a group of long non-coding RNAs, which are reported in many studies as being overexpressed in various cancers. With very few exceptions, the SNHGs (SNHG1, SNHG3, SNHG5, SNHG6, SNHG7, SNHG12, SNHG15, SNHG16, SNHG20) are recognized as inducing increased proliferation, cell cycle progression, invasion, and metastasis of cancer cells, which makes this class of transcripts a viable biomarker for cancer development and aggressiveness. Through our literature research, we also found that silencing of SNHGs through small interfering RNAs or short hairpin RNAs is very effective in both in vitro and in vivo experiments by lowering the aggressiveness of solid cancers. The knockdown of SNHG as a new cancer therapeutic option should be investigated more in the future.

Altered expression of miR-181 affects cell fate and targets drug resistance-related mechanisms

MicroRNAs (miRNAs) are non-coding transcripts which regulate genetic and epigenetic events by interfering with mRNA translation. miRNAs are involved in regulation of cell fate due to their ability of interfering with physiological or pathological processes. In this review paper, we evaluate the role of miR-181 family members as prognostic or diagnostic markers or therapeutic targets in malignant pathologies in connection with the main hallmarks of cancer that are modulated by the family. Also, we take over the dual role of this family in dependency with the tumour suppressor and oncogenic features presented in cell and cancer type specific manner. Restoration of the altered expression levels contributes to the activation of cell death pathways or to a reduction in the invasion and migration mechanism; moreover, the mechanism of drug resistance is also modulated by miR-181 sequences with important applications in therapeutic strategies for malignant cells sensitisation. Overall, the main miR-181 family regulatory mechanisms are presented in a cancer specific context, emphasizing the possible clinical application of this family in terms of novel diagnosis and therapy approaches.

Long Non-coding RNAs in Myeloid Malignancies

Acute myeloid leukemia (AML) represents 80% of adult leukemias and 15-20% of childhood leukemias. AML are characterized by the presence of 20% blasts or more in the bone marrow, or defining cytogenetic abnormalities. Laboratory diagnoses of myelodysplastic syndromes (MDS) depend on morphological changes based on dysplasia in peripheral blood and bone marrow, including peripheral blood smears, bone marrow aspirate smears, and bone marrow biopsies. As leukemic cells are not functional, the patient develops anemia, neutropenia, and thrombocytopenia, leading to fatigue, recurrent infections, and hemorrhage. The genetic background and associated mutations in AML blasts determine the clinical course of the disease. Over the last decade, non-coding RNAs transcripts that do not codify for proteins but play a role in regulation of functions have been shown to have multiple applications in the diagnosis, prognosis and therapeutic approach of various types of cancers, including myeloid malignancies. After a comprehensive review of current literature, we found reports of multiple long non-coding RNAs (lncRNAs) that can differentiate between AML types and how their exogenous modulation can dramatically change the behavior of AML cells. These lncRNAs include: H19, LINC00877, RP11-84C10, CRINDE, RP11848P1.3, ZNF667-AS1, AC111000.4-202, SFMBT2, LINC02082-201, MEG3, AC009495.2, PVT1, HOTTIP, SNHG5, and CCAT1. In addition, by performing an analysis on available AML data in The Cancer Genome Atlas (TCGA), we found 10 lncRNAs with significantly differential expression between patients in favorable, intermediate/normal, or poor cytogenetic risk categories. These are: DANCR, PRDM16-DT, SNHG6, OIP5-AS1, SNHG16, JPX, FTX, KCNQ1OT1, TP73-AS1, and GAS5. The identification of a molecular signature based on lncRNAs has the potential for have deep clinical significance, as it could potentially help better define the evolution from low-grade MDS to high-grade MDS to AML, changing the course of therapy. This would allow clinicians to provide a more personalized, patient-tailored therapeutic approach, moving from transfusion-based therapy, as is the case for low-grade MDS, to the introduction of azacytidine-based chemotherapy or allogeneic stem cell transplantation, which is the current treatment for high-grade MDS.

Identification of Transcriptional Markers and microRNA-mRNA Regulatory Networks in Colon Cancer by Integrative Analysis of mRNA and microRNA Expression Profiles in Colon Tumor Stroma

The aberrant expression of microRNAs (miRNAs) and genes in tumor microenvironment (TME) has been associated with the pathogenesis of colon cancer. An integrative exploration of transcriptional markers (gene signatures) and miRNA–mRNA regulatory networks in colon tumor stroma (CTS) remains lacking. Using two datasets of mRNA and miRNA expression profiling in CTS, we identified differentially expressed miRNAs (DEmiRs) and differentially expressed genes (DEGs) between CTS and normal stroma. Furthermore, we identified the transcriptional markers which were both gene targets of DEmiRs and hub genes in the protein–protein interaction (PPI) network of DEGs. Moreover, we investigated the associations between the transcriptional markers and tumor immunity in colon cancer. We identified 17 upregulated and seven downregulated DEmiRs in CTS relative to normal stroma based on a miRNA expression profiling dataset. Pathway analysis revealed that the downregulated DEmiRs were significantly involved in 25 KEGG pathways (such as TGF-β, Wnt, cell adhesion molecules, and cytokine–cytokine receptor interaction), and the upregulated DEmiRs were involved in 10 pathways (such as extracellular matrix (ECM)-receptor interaction and proteoglycans in cancer). Moreover, we identified 460 DEGs in CTS versus normal stroma by a meta-analysis of two gene expression profiling datasets. Among them, eight upregulated DEGs were both hub genes in the PPI network of DEGs and target genes of the downregulated DEmiRs. We found that three of the eight DEGs were negative prognostic factors consistently in two colon cancer cohorts, including COL5A2, EDNRA, and OLR1. The identification of transcriptional markers and miRNA–mRNA regulatory networks in CTS may provide insights into the mechanism of tumor immune microenvironment regulation in colon cancer.

Roles of long non-coding RNAs in colorectal cancer tumorigenesis: A Review

Long non-coding RNAs (lncRNAs) are newly identified potential biological and gene regulators. Similar to other cell-free circulating cancer-related nucleic acids, lncRNAs are released in the peripheral circulation of cancer patients and allow for non-invasive gene expression assessment. lncRNAs are considered to be promising biomarkers for cancer prognosis and diagnosis. Several lncRNAs have been found to regulate developmental processes in a number of biological disorders. Recent studies indicated that lncRNAs are associated with numerous diseases, most notably cancer, as they were found to be highly expressed or silenced in a number of human cancers, including colorectal cancer (CRC). Despite advances in the current detection methods, over half of cancer patients succumb to the disease, as several CRC cases are diagnosed at an advanced stage. Due to the lack of non-invasive and low-cost prognostic and diagnostic tests for CRC, the identification of novel, potentially effective biomarkers has been attracting increasing attention in recent cancer research. The present review focused on the most widely applied lncRNAs in cancer detection, including CRC, in vitro.

Forms of extracellular mitochondria and their impact in health

Mitochondria play an important role as an intracellular energy plant and signaling organelle. However, mitochondria also exist outside cells where they could mediate cell-to-cell communication, repair and serve as an activator of the immune response. Their effects depend on the mitochondrial state or the form in which it is present, either as a whole functional structure as fragments or only as mitochondrial DNA. Herein, we provide evidence of why extracellular mitochondria and their varying forms are considered regenerative factors or pro-inflammatory activators. Understanding these aspects will provide the base of their use in therapy or as a biomarker of disease severity and prognosis.

miR-181a/b therapy in lung cancer: reality or myth?

Despite substantial progress in oncology, lung cancer remains the number one malignancy in terms of both incidence and mortality rates, and there thus remains an urgent need for new therapeutic alternatives. MicroRNA (miRNA) have an important role in cancer initiation and progression due to their capacity to interfere with transcriptional signaling and regulate key cellular processes. miR-181a and miR-181b (miR-181a/b), which are located on chromosomes 1 and 9, are pathologically expressed in the tumor tissue and plasma of patients diagnosed with lung cancer. The miR-181a/b regulatory mechanisms are sophisticated and are directly related to different target genes. In recent years, an ever-increasing number of studies have focused on the biological relevance of miR-181a/b in key cellular processes. In this paper, we aim to discuss the challenging experimental data related to miR-181a/b and their potential use for the development of new therapeutic approaches in lung cancer. We will further present the ongoing issues regarding the regulation of their multiple target genes, and their potential use as biomarkers and therapeutic targets in this deadly malignancy.

Aberrant miRNAs expressed in HER-2 negative breast cancers patient

Background

Breast cancer is a highly heterogeneous pathology, exhibiting a number of subtypes commonly associated with a poor outcome. Due to their high stability, microRNAs are often regarded as non-invasive cancer biomarkers, having an expression pattern specific for their ‘cell of origin’.

Method

Triple negative breast cancer (TNBC: ER-, PR-, Her-2-) and double positive breast cancer (DPBC: ER+, PR+, Her-2) miRNA expression patterns were obtained by analysis of the TCGA (The Cancer Genome Atlas) data, followed by PCR-array analysis on plasma samples from 20 TNBC patients, 14 DPBC patients and 11 controls.

Results

Three downregulated and nine upregulated miRNAs were obtained from the TNBC analysis. Five overexpressed miRNAs were identified in the DPBC group. Four of the dysregulated miRNAs (miR-10a, miR-125b, miR-210 and miR-489) were common for both groups. The cluster miR-17-92 (miR-17, miR-20a, miR-20b, and miR-93), along with miR-130, miR-22 and miR-29a/c, were found to differentiate between TNBC and DPBC. A panel of five transcripts (miR-10a, miR-125, miR-193b, miR-200b and miR-489) was validated in a new set of plasma samples. The overlapping of TCGA and plasma profiling data revealed miR-200b, miR-200c, miR-210 and miR-29c as common signature. MiR-200b was validated on additional normal and tumor tissue samples. The expression level of this transcript from the TCGA data was correlated with lung and bone metastatic genes.

Conclusion

The miR-200b presents a great potential for the future advancements in the diagnostic/prognostic and therapeutic approach of TNBC, along with other coding or non-coding transcripts. However, this needs to be further integrated in a regulatory network that acts in conjunction with other markers that affect the patients’ prognosis or response to therapy.

Electronic supplementary material

The online version of this article (10.1186/s13046-018-0920-2) contains supplementary material, which is available to authorized users.

RNA interference: new mechanistic and biochemical insights with application in oral cancer therapy

Over the last few decades, the incidence of oral cancer has gradually increased, due to the negative influence of environmental factors and also abnormalities within the genome. The main issues in oral cancer treatment consist in surpassing resistance and recurrence. However, continuous discovery of altered signaling pathways in these tumors provides valuable information for the identification of novel gene candidates targeted in personalized therapy. RNA interference (RNAi) is a natural mechanism that involves small interfering RNA (siRNA); this can be exploited in biomedical research by using natural or synthetic constructs for activation of the mechanism. Synthetic siRNA transcripts were developed as a versatile class of molecular tools that have a diverse range of programmable roles, being involved in the regulation of several biological processes, thereby providing the perspective of an alternative option to classical treatment. In this review, we summarize the latest information related to the application of siRNA in oral malignancy together with molecular aspects of the technology and also the perspective upon the delivery system. Also, the emergence of newer technologies such as clustered regularly interspaced short palindromic repeats/Cas9 or transcription activator-like effector nucleases in comparison with the RNAi approach is discussed in this paper.

lncRNA CCAT1 promotes cell proliferation, migration, and invasion by down-regulation of miR-143 in FTC-133 thyroid carcinoma cell line

Thyroid cancer is a common malignant tumor. Long non-coding RNA colon cancer-associated transcript 1 (lncRNA CCAT1) is highly expressed in many cancers; however, the molecular mechanism of CCAT1 in thyroid cancer remains unclear. Hence, this study aimed to investigate the effect of CCAT1 on human thyroid cancer cell line FTC-133. FTC-133 cells were transfected with CCAT1 expressing vector, CCAT1 shRNA, miR-143 mimic, and miR-143 inhibitor, respectively. After different treatments, cell viability, proliferation, migration, invasion, and apoptosis were measured. Moreover, the regulatory relationship of CCAT1 and miR-143, as well as miR-143 and VEGF were tested using dual-luciferase reporter assay. The relative expressions of CCAT1, miR-143, and VEGF were tested by qRT-PCR. The expressions of apoptosis-related factors and corresponding proteins in PI3K/AKT and MAPK pathways were analyzed using western blot analysis. The results suggested that CCAT1 was up-regulated in the FTC-133 cells. CCAT1 suppression decreased FTC-133 cell viability, proliferation, migration, invasion, and miR-143 expression, while it increased apoptosis and VEGF expression. CCAT1 might act as a competing endogenous RNA (ceRNA) for miR-143. Moreover, CCAT1 activated PI3K/AKT and MAPK signaling pathways through inhibition of miR-143. This study demonstrated that CCAT1 exhibited pro-proliferative and pro-metastasis functions on FTC-133 cells and activated PI3K/AKT and MAPK signaling pathways via down-regulation of miR-143. These findings will provide a possible target for clinical treatment of thyroid cancer.

Natural products with anti-aging potential: Affected targets and molecular mechanisms

In recent years, there has been a great deal of attention toward the molecular machinery relevant to age-related progression controlled through the external intervention of polyphenols- an epigenetic-modulating diet. Natural products modulate cellular longevity through histone post-translational modification and can also induce the upregulation of autophagy, thus reducing the level of acetyl coenzyme A (AcCoA). In addition, the effect of caloric restriction (CR) on cancer-related chronic inflammation is of great significance in aging. In line with this, SIRT1 protein levels are expanded in response to calorie restriction mimetics (CRM), in this way acting as autophagy inducers relevant to cancer prevention.

The Unforeseen Non-Coding RNAs in Head and Neck Cancer

Previously ignored non-coding RNAs (ncRNAs) have become the subject of many studies. However, there is an imbalance in the amount of consideration that ncRNAs are receiving. Some transcripts such as microRNAs (miRNAs) or small interfering RNAs (siRNAs) have gained much attention, but it is necessary to investigate other “pieces of the RNA puzzle”. These can offer a more complete view over normal and pathological cell behavior. The other ncRNA species are less studied, either due to their recent discovery, such as stable intronic sequence RNA (sisRNA), YRNA, miRNA-offset RNAs (moRNA), telomerase RNA component (TERC), natural antisense transcript (NAT), transcribed ultraconserved regions (T-UCR), and pseudogene transcript, or because they are still largely seen as non-coding transcripts with no relevance to pathogenesis. Moreover, some are still considered housekeeping RNAs, for instance small nucleolar RNAs (snoRNAs) and TERC. Our review summarizes the biogenesis, mechanism of action and potential role of less known ncRNAs in head and neck cancer, with a particular focus on the installment and progress for this particular cancer type.

Puerarin Inhibits Proliferation and Induces Apoptosis by Upregulation of miR-16 in Bladder Cancer Cell Line T24

Bladder cancer (BC) is a common disease of the urinary system. Puerarin is a flavonoid extracted from Pueraria lobata. However, the role of puerarin in BC remains unclear. Hence, this study aimed to investigate the effect of puerarin on BC cells. Cell viability, proliferation, and apoptosis were measured by CCK-8, BrdU assay, and flow cytometry analysis, respectively. The expressions of miR-16, apoptosis-related factors, and the main factors of the NF-κB pathway were analyzed by qRT-PCR and Western blot. In this study, we found that cell viability and proliferation were significantly reduced, cell apoptosis was enhanced, and the mRNA level of miR-16 was upregulated in puerarin-treated T24 cells. Further, silencing of miR-16 inhibited the decrease in cell viability and the increase in apoptosis. The expression of main factors involved in the NF-κB signaling pathway was downregulated in the puerarin group, while miR-16 silencing alleviated these downregulations. More importantly, puerarin deactivated the NF-κB signaling pathway via upregulation of miR-16. Also, miR-16 downregulated COX-2 expression via deactivation of the NF-κB signaling pathway. This study demonstrated that puerarin could inhibit cell proliferation, promote cell apoptosis, and deactivate NF-κB signaling pathway via upregulation of miR-16 in T24 cells.

Inhibition of autophagy potentiates the proliferation inhibition activity of microRNA-7 in human hepatocellular carcinoma cells

MicroRNAs (miRNAs/miRs) are important molecules that are able to regulate multiple cellular processes in cancer cells. miR-7 has been previously identified as a tumor suppressive miRNA in several types of cancer. The aim of the present study was to investigate whether miR-7 is able to regulate autophagy in hepatocellular carcinoma (HCC) cells. It was identified that miR-7 was significantly downregulated in tumor tissues compared with adjacent normal tissues. Overexpression of miR-7 inhibited cell proliferative activity, which was partially reversed by miR-7 inhibitor. In addition, overexpression of miR-7 significantly induced an increasen in autophagic activity, and luciferase activity assay and western blot analysis identified that mammalian target of rapamycin (mTOR) was a direct target of miR-7. In addition, inhibition of autophagy by 3-methyladenine resulted in a marked enhancement of the proliferation inhibition effect of miR-7. In conclusion, miR-7 was identified to induce proliferation inhibition and autophagy in HCC cells by targeting mTOR, and inhibition of autophagy may be utilized to enhance the antitumor activity of miR-7.