MicroRNA-99a inhibits hepatocellular carcinoma growth and correlates with prognosis of patients with hepatocellular carcinoma

miRNAs in HCC, pathogenesis, and targets

Liver cancer is the third leading cause of cancer-related mortality worldwide. HCC, the most common type of primary liver cancer, is driven by complex genetic, epigenetic, and environmental factors. MicroRNAs, a class of naturally occurring small noncoding RNAs, play crucial roles in HCC by simultaneously modulating the expression of multiple genes in a fine-tuning manner. Significant progress has been made in understanding how miRNAs influence key oncogenic pathways, including cell proliferation, apoptosis, angiogenesis, and epithelial-mesenchymal transition (EMT), as well as their role in modulating the immune microenvironment in HCC. Due to the unexpected stability of miRNAs in the blood and fixed HCC tumors, recent advancements also highlight their potential as noninvasive diagnostic tools. Restoring or inhibiting specific miRNAs has offered promising strategies for targeted HCC treatment by suppressing malignant hepatocyte growth and enhancing antitumor immunity. In this comprehensive review, we consolidate previous research and provide the latest insights into how miRNAs regulate HCC and their therapeutic and diagnostic potential. We delve into the dysregulation of miRNA biogenesis in HCC, the roles of miRNAs in the proliferation and apoptosis of malignant hepatocytes, angiogenesis and metastasis of HCC, the immune microenvironment in HCC, and drug resistance. We also discuss the therapeutic and diagnostic potential of miRNAs and delivery approaches of miRNA drugs to overcome the limitations of current HCC treatment options. By thoroughly summarizing the roles of miRNAs in HCC, our goal is to advance the development of effective therapeutic drugs with minimal adverse effects and to establish precise tools for early diagnosis of HCC.

The Predictive Role of miRNAs in Hepatitis B Vaccine Response of Metabolic Dysfunction-Associated Steatotic Liver Disease Patients

(1) Background: Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most common chronic liver disease. Although the changes in the expression levels of microRNAs (miRNAs) in hepatitis B virus-related diseases have been evaluated, no study has evaluated the role of miRNAs in HBV vaccine response in MASLD patients. We aimed to determine the miRNA expression profile in MASLD patients according to HBV vaccine response. (2) Methods: Overall, 100 MASLD patients and 100 controls were included, and anti-HBs levels were measured after three doses of HBV vaccine administration. After collecting blood samples, 22 different miRNA expression profiles were analyzed by RT-PCR analysis, and changes in the expression levels of potential miRNAs were further verified in all study groups. (3) Results: The miR-146a expression level considerably increased in MASLD patients compared to the control group. Furthermore, miR-99a and miR-640 expression levels significantly increased in AntiHBs (-) healthy individuals. (4): Conclusions: miR-146a could be used as the diagnostic marker in MASLD patients. Furthermore, the miR-99a and miR-640 expression levels could predict hepatitis B vaccine response. However, validation studies are required to verify the biomarker potential of miRNAs within a more significant number of patients.

MiR-99a-5p up-regulates LDLR and functionally enhances LDL-C uptake via suppressing PCSK9 expression in human hepatocytes

Background

MicroRNAs (miRs/miRNAs) play pivotal roles in modulating cholesterol homeostasis. Proprotein convertase subtilisin/kexin type 9 (PCSK9) binds to low-density lipoprotein receptor (LDLR) at the surface of hepatocytes and accelerates its degradation in lysosomes, thereby impairing the clearance of circulating low-density lipoprotein cholesterol (LDL-C) from plasma. Thus, suppressing PCSK9 expression level has become an effective approach for treating hypercholesterolemia. Here, we sought to identify novel miRNAs that inhibit PCSK9 expression.

Methods

By in silico analyses, miR-99a-5p was predicted to bind to human PCSK9 mRNA. Following transfection of miR-99a-5p or anti-miR-99a-5p in human and mouse hepatocytes, qRT-PCR, Western blot, immunofluorescence, ELISA, flow cytometry, LDL-C uptake, and cellular cholesterol measurement were performed.

Results

miR-99a-5p overexpression potently inhibited PCSK9 expression, thereby up-regulating LDLR, functionally enhancing LDL-C uptake and increasing intracellular cholesterol levels in human, but not in mouse, cells. Conversely, anti-miR-99a-5p upregulates PCSK9, leading to a reduction in LDLR, attenuation of LDL-C uptake, and a decrease in the intracellular cholesterol levels of human hepatocytes. Furthermore, miR-99a-5p was shown to bind to the predicted target site "UACGGGU" in the 3'-UTR of human PCSK9 mRNA via a luciferase reporter assay in combination with site-directed mutagenesis.

Conclusion

MiR-99a-5p potently downregulates the expression of PCSK9 by directly interacting with a target site in the human PCSK9 3'-UTR, thereby up-regulating LDLR and functionally enhancing LDL-C uptake in human hepatocytes. MiR-99a-5p could serve as an inhibitor of PCSK9 for treating hypercholesterolemia to inhibit atherosclerosis.

Differential Hepatic Expression of miRNA in Response to Aflatoxin B1 Challenge in Domestic and Wild Turkeys

Aflatoxin B1 (AFB1) is a major foodborne mycotoxin that poses a significant economic risk to poultry due to a greater degree of susceptibility compared to other agricultural species. Domesticated turkeys (Meleagris gallopavo) are especially sensitive to AFB1; however, wild turkeys (M. g. silvestris) are more resistant. A lack of functional isoforms of hepatic glutathione S-transferases (GSTs), an enzyme that plays a role in the detoxification of aflatoxin, is suspected as the reason for the increased sensitivity. Previous studies comparing the gene expression of domesticated and wild turkeys exposed to AFB1 identified hepatic genes responding differentially to AFB1, but could not fully explain the difference in response. The current study examined differences in the expression of microRNAs (miRNAs) in the livers of wild and domesticated turkeys fed dietary AFB1 (320 μg/kg in feed). Short-read RNA sequencing and expression analysis examined both domesticated and wild turkeys exposed to AFB1 compared to controls. A total of 25 miRNAs was identified as being significantly differentially expressed (DEM) in pairwise comparisons. The majority of these have mammalian orthologs with known dysregulation in liver disease. The largest number of DEMs occurred between controls, suggesting an underlying difference in liver potential. Sequences of the DEMs were used to identify potential miRNA binding sites in target genes, resulting in an average of 4302 predicted target sites per DEM. These DEMs and gene targets provide hypotheses for future investigations into the role of miRNAs in AFB1 resistance.

Non-coding RNA mediated regulation of PI3K/Akt pathway in hepatocellular carcinoma: Therapeutic perspectives

Hepatocellular carcinoma (HCC) is among the primary reasons for fatalities caused by cancer globally, highlighting the need for comprehensive knowledge of its molecular aetiology to develop successful treatment approaches. The PI3K/Akt system is essential in the course of HCC, rendering it an intriguing candidate for treatment. Non-coding RNAs (ncRNAs), such as long ncRNAs (lncRNAs), microRNAs (miRNAs), and circular RNAs (circRNAs), are important mediators of the PI3K/Akt network in HCC. The article delves into the complex regulatory functions of ncRNAs in influencing the PI3K/Akt system in HCC. The study explores how lncRNAs, miRNAs, and circRNAs impact the expression as well as the function of the PI3K/Akt network, either supporting or preventing HCC growth. Additionally, treatment strategies focusing on ncRNAs in HCC are examined, such as antisense oligonucleotide-based methods, RNA interference, and small molecule inhibitor technologies. Emphasizing the necessity of ensuring safety and effectiveness in clinical settings, limitations, and future approaches in using ncRNAs as therapies for HCC are underlined. The present study offers useful insights into the complex regulation system of ncRNAs and the PI3K/Akt cascade in HCC, suggesting possible opportunities for developing innovative treatment approaches to address this lethal tumor.

Exploring non-coding RNA mechanisms in hepatocellular carcinoma: implications for therapy and prognosis

Hepatocellular carcinoma (HCC) is a significant contributor to cancer-related deaths in the world. The development and progression of HCC are closely correlated with the abnormal regulation of non-coding RNAs (ncRNAs), such as microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs). Important biological pathways in cancer biology, such as cell proliferation, death, and metastasis, are impacted by these ncRNAs, which modulate gene expression. The abnormal expression of non-coding RNAs in HCC raises the possibility that they could be applied as new biomarkers for diagnosis, prognosis, and treatment targets. Furthermore, by controlling the expression of cancer-related genes, miRNAs can function as either tumor suppressors or oncogenes. On the other hand, lncRNAs play a role in the advancement of cancer by interacting with other molecules within the cell, which, in turn, affects processes such as chromatin remodeling, transcription, and post-transcriptional processes. The importance of ncRNA-driven regulatory systems in HCC is being highlighted by current research, which sheds light on tumor behavior and therapy response. This research highlights the great potential of ncRNAs to improve patient outcomes in this difficult disease landscape by augmenting the present methods of HCC care through the use of precision medicine approaches.

Non-coding RNAs as potential therapeutic targets for receptor tyrosine kinase signaling in solid tumors: current status and future directions

This review article presents an in-depth analysis of the current state of research on receptor tyrosine kinase regulatory non-coding RNAs (RTK-RNAs) in solid tumors. RTK-RNAs belong to a class of non-coding RNAs (nc-RNAs) responsible for regulating the expression and activity of receptor tyrosine kinases (RTKs), which play a critical role in cancer development and progression. The article explores the molecular mechanisms through which RTK-RNAs modulate RTK signaling pathways and highlights recent advancements in the field. This include the identification of potential new RTK-RNAs and development of therapeutic strategies targeting RTK-RNAs. While the review discusses promising results from a variety of studies, encompassing in vitro, in vivo, and clinical investigations, it is important to acknowledge the challenges and limitations associated with targeting RTK-RNAs for therapeutic applications. Further studies involving various cancer cell lines, animal models, and ultimately, patients are necessary to validate the efficacy of targeting RTK-RNAs. The specificity of ncRNAs in targeting cellular pathways grants them tremendous potential, but careful consideration is required to minimize off-target effects, the article additionally discusses the potential clinical applications of RTK-RNAs as biomarkers for cancer diagnosis, prognosis, and treatment. In essence, by providing a comprehensive overview of the current understanding of RTK-RNAs in solid tumors, this review emphasizes their potential as therapeutic targets for cancer while acknowledging the associated challenges and limitations.

Differential effects of microRNAs miR-21, miR-99 and miR-145 on lung regeneration and inflammation during recovery from influenza pneumonia

In a mouse model of influenza pneumonia, we previously documented that proliferating alveolar type II (AT2) cells are the major stem cells involved in early lung recovery. Profiling of microRNAs revealed significant dysregulation of specific ones, including miR-21 and miR-99a. Moreover, miR-145 is known to exhibit antagonism to miR-21. This follow-up study investigated the roles of microRNAs miR-21, miR-99a, and miR-145 in the murine pulmonary regenerative process and inflammation during influenza pneumonia. Inhibition of miR-21 resulted in severe morbidity, and in significantly decreased proliferating AT2 cells due to impaired transition from innate to adaptive immune responses. Knockdown of miR-99a culminated in moderate morbidity, with a significant increase in proliferating AT2 cells that may be linked to PTEN downregulation. In contrast, miR-145 antagonism did not impact morbidity nor the proliferating AT2 cell population, and was associated with downregulation of TNF-alpha, IL1-beta, YM1, and LY6G. Hence, a complex interplay exists between expression of specific miRNAs, lung regeneration, and inflammation during recovery from influenza pneumonia. Inhibition of miR-21 and miR-99a (but not miR-145) can lead to deleterious cellular and molecular effects on pulmonary repair and inflammatory processes during influenza pneumonia.

MiRNAs in Alcohol-Related Liver Diseases and Hepatocellular Carcinoma: A Step toward New Therapeutic Approaches?

Alcohol-related Liver Disease (ALD) is the primary cause of chronic liver disorders and hepatocellular carcinoma (HCC) development in developed countries and thus represents a major public health concern. Unfortunately, few therapeutic options are available for ALD and HCC, except liver transplantation or tumor resection for HCC. Deciphering the molecular mechanisms underlying the development of these diseases is therefore of major importance to identify early biomarkers and to design efficient therapeutic options. Increasing evidence indicate that epigenetic alterations play a central role in the development of ALD and HCC. Among them, microRNA importantly contribute to the development of this disease by controlling the expression of several genes involved in hepatic metabolism, inflammation, fibrosis, and carcinogenesis at the post-transcriptional level. In this review, we discuss the current knowledge about miRNAs' functions in the different stages of ALD and their role in the progression toward carcinogenesis. We highlight that each stage of ALD is associated with deregulated miRNAs involved in hepatic carcinogenesis, and thus represent HCC-priming miRNAs. By using in silico approaches, we have uncovered new miRNAs potentially involved in HCC. Finally, we discuss the therapeutic potential of targeting miRNAs for the treatment of these diseases.

Effect of down-regulation of let-7c/g on triggering a double-negative feedback loop and promoting restenosis

BACKGROUND

Excessive proliferation and migration of vascular smooth muscle cells (VSMCs) are the main causes of restenosis (RS) in diabetic lower extremity arterial disease (LEAD). However, the relevant pathogenic mechanisms are poorly understood.

METHODS

In this study, we introduced a "two-step injury protocol" rat RS model, which started with the induction of atherosclerosis (AS) and was followed by percutaneous transluminal angioplasty (PTA). Hematoxylin-eosin (HE) staining and immunohistochemistry staining were used to verify the form of RS. Two-step transfection was performed, with the first transfection of Lin28a followed by a second transfection of let-7c and let-7g, to explore the possible mechanism by which Lin28a exerted effects. 5-ethynyl-2΄-deoxyuridine (EdU) and Transwell assay were performed to evaluate the ability of proliferation and migration of VSMCs. Western blotting and quantitative real-time polymerase chain reaction (qRT-PCR) were performed to detect the expression of Lin28a protein and let-7 family members.

RESULTS

Using a combination of in vitro and in vivo experiments, we discovered that let-7c, let-7g, and microRNA98 (miR98) were downstream targets of Lin28a. More importantly, decreased expression of let-7c/let-7g increased Lin28a, leading to further inhibition of let-7c/let-7g. We also found an increased level of let-7d in the RS pathological condition, suggesting that it may function as a protective regulator of the Lin28a/let-7 loop by inhibiting the proliferation and migration of VSMCs.

CONCLUSION

These findings indicated the presence of a double-negative feedback loop consisting of Lin28a and let-7c/let-7g, which may be responsible for the vicious behavior of VSMCs in RS.

EZH2-mediated epigenetic silencing of tumor-suppressive let-7c/miR-99a cluster by hepatitis B virus X antigen enhances hepatocellular carcinoma progression and metastasis

BACKGROUND

Hepatitis B virus (HBV)-encoded X antigen, HBx, assists in the development of hepatocellular carcinoma (HCC) through complex mechanisms. Our results provide new insights into the EZH2 epigenetic repression of let-7c that promotes HCC migration induced by HBx. Thus, let-7c and HMGA2 represent key diagnostic markers and potential therapeutic targets for the treatment of HBV-related HCC.

RESULTS

We investigated the epigenetic regulation of let-7c, an important representative miRNA in liver tumor metastasis, in human HCC cells to verify the effect of HBx. Based on quantitative PCR (qPCR) of mRNA isolated from tumor and adjacent non-tumor liver tissues of 24 patients with HBV-related HCC, EZH2 expression was significantly overexpressed in most HCC tissues (87.5%). We executed a miRNA microarray analysis in paired HBV-related HCC tumor and adjacent non-tumorous liver tissue from six of these patients and identified let-7c, miR-199a-3p, and miR-99a as being downregulated in the tumor tissue. Real-time PCR analysis verified significant downregulation of let-7c and miR-99a in both HepG2X and Hep3BX cells, which stably overexpress HBx, relative to parental cells. HBX enhanced EZH2 expression and attenuated let-7c expression to induce HMGA2 expression in the HCC cells. Knockdown of HMGA2 significantly downregulated the metastatic potential of HCC cells induced by HBx.

CONCLUSIONS

The deregulation of let-7c expression by HBx may indicate a potential novel pathway through deregulating cell metastasis and imply that HMGA2 might be used as a new prognostic marker and/or as an effective therapeutic target for HCC.

Emerging role of MicroRNA-Based theranostics in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC), with its high mortality and short survival rate, continues to be one of the deadliest malignancies despite relentless efforts and several technological advances. The poor prognosis of HCC and the few available treatments are to blame for the low survival rate, which emphasizes the importance of creating new, effective diagnostic markers and innovative therapy strategies. In-depth research is being done on the potent biomarker miRNAs, a special class of non-coding RNA and has shown encouraging results in the early identification and treatment of HCC in order to find more viable and successful therapeutics for the disease. It is beyond dispute that miRNAs control cell differentiation, proliferation, and survival and, depending on the genes they target, can either promote tumorigenesis or suppress it. Given the vital role miRNAs play in the biological system and their potential to serve as ground-breaking treatments for HCC, more study is required to fully examine their theranostic potential.

Targeting EGFR/PI3K/AKT/mTOR Signaling in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) poses a significant global health concern, with its incidence steadily increasing. The development of HCC is a multifaceted, multi-step process involving alterations in various signaling cascades. In recent years, significant progress has been made in understanding the molecular signaling pathways that play central roles in hepatocarcinogenesis. In particular, the EGFR/PI3K/AKT/mTOR signaling pathway in HCC has garnered renewed attention from both basic and clinical researchers. Preclinical studies in vitro and in vivo have shown the effectiveness of targeting the key components of this signaling pathway in human HCC cells. Thus, targeting these signaling pathways with small molecule inhibitors holds promise as a potential therapeutic option for patients with HCC. In this review, we explore recent advancements in understanding the role of the EGFR/PI3K/AKT/mTOR signaling pathway in HCC and assess the effectiveness of targeting this signaling cascade as a potential strategy for HCC therapy based on preclinical studies.

The mirrored cationic peptide as miRNA vehicle for efficient lung cancer therapy

Gene therapy has emerged as a potential approach for lung cancer therapy. However, the application of gene therapy is still limited by their properties, such as low specificity to the cancer cells, negatively charged groups, short systemic circulation time, and rapid degradation by nucleases. The progression of lung adenocarcinoma (LUAD) can be promoted through the methylation process of miR-148a-3p promoter, as confirmed by our previous research. In the current study, we are the first to design a mirrored Arg-Gly-Asp (RGD)-modified cationic peptide (RD24) as a microRNA (miRNA) vehicle, which enabled to pack the miRNA (miR-148a-3p) efficiently and generate RD24/miR-148a-3p nanoparticles (RPRIN) by self-assembling. RPRIN exhibited a high transfection efficiency in lung cancer cells via the conjugation between RGD and integrins on the surface of lung cancer cells. Furthermore, RD24 showed matrix metallopeptidase 2 (MMP2) responsiveness, which improved lung cancer cell inhibition induced by the miRNA intracellularly. In addition, RPRIN exhibits several advantages, such as prolonged circulation duration, reduced toxicity, and immune escape. Experiments conducted both in vitro and in vivo revealed that RPRIN effectively suppressed the growth and progression of lung cancer. Thus, the mirrored RGD-modified cationic peptide showed great potential in transducing miRNA for lung cancer therapy.

Circulating MicroRNAs: Diagnostic Value as Biomarkers in the Detection of Non-alcoholic Fatty Liver Diseases and Hepatocellular Carcinoma

Non-alcoholic fatty liver disease (NAFLD), a metabolic-related disorder, is the most common cause of chronic liver disease which, if left untreated, can progress from simple steatosis to advanced fibrosis and eventually cirrhosis or hepatocellular carcinoma, which is the leading cause of hepatic damage globally. Currently available diagnostic modalities for NAFLD and hepatocellular carcinoma are mostly invasive and of limited precision. A liver biopsy is the most widely used diagnostic tool for hepatic disease. But due to its invasive procedure, it is not practicable for mass screening. Thus, noninvasive biomarkers are needed to diagnose NAFLD and HCC, monitor disease progression, and determine treatment response. Various studies indicated that serum miRNAs could serve as noninvasive biomarkers for both NAFLD and HCC diagnosis because of their association with different histological features of the disease. Although microRNAs are promising and clinically useful biomarkers for hepatic diseases, larger standardization procedures and studies are still required.

The Role of miRNAs, circRNAs and Their Interactions in Development and Progression of Hepatocellular Carcinoma: An Insilico Approach

Hepatocellular carcinoma (HCC) is a type of malignant tumor. miRNAs are noncoding RNAs and their differential expression patterns are observed in HCC-induced by alcoholism, HBV and HCV infections. By acting as a competing endogenous RNA (ceRNA), circRNA regulates the miRNA function, indirectly controlling the gene expression and leading to HCC progression. In the present study, data mining was performed to screen out all miRNAs and circRNA involved in alcohol, HBV or HCV-induced HCC with statistically significant (≤0.05%) expression levels reported in various studies. Further, the interaction of miRNAs and circRNA was also investigated to explore their role in HCC due to various causative agents. Together, these study data provide a deeper understanding of the circRNA-miRNA regulatory mechanisms in HCC. These screened circRNA, miRNA and their interactions can be used as prognostic biomarkers or therapeutic targets for the treatment of HCC.

HCV and tumor-initiating stem-like cells

Neoplasms contain tumor-initiating stem-like cells (TICs) that are characterized by increased drug resistance. The incidence of many cancer types have trended downward except for few cancer types, including hepatocellular carcinoma (HCC). Therefore mechanism of HCC development and therapy resistance needs to be understood. These multiple hits by hepatitis C virus (HCV) eventually promotes transformation and TIC genesis, leading to HCC development. This review article describes links between HCV-associated HCC and TICs. This review discusses 1) how HCV promotes genesis of TICs and HCC development; 2) how this process avails itself as a novel therapeutic target for HCC treatment; and 3) ten hall marks of TIC oncogenesis and HCC development as targets for novel therapeutic modalities.

miRNAs inspirations in hepatocellular carcinoma: Detrimental and favorable aspects of key performers

Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer-related deaths worldwide. HCC initiation, progression, and therapy failure are all influenced by various variables, including microRNAs (miRNAs). miRNAs are short non-coding RNA sequences that modulate target mRNA expression by deteriorating or repressing translation. miRNAs play an imperative role in HCC pathogenesis by triggering the induction of cancer stem cells (CSCs) and their proliferation, while also delaying apoptosis, sustaining the cell cycle, and inspiring angiogenesis, invasion, and metastasis. Additionally, miRNAs modulate crucial HCC-related molecular pathways such as the p53 pathway, the Wnt/β-catenin pathway, VEGFR2, and PTEN/PI3K/AKT pathway. Consequently, the goal of this review was to give an up-to-date overview of oncogenic and tumor suppressor (TS) miRNAs, as well as their potential significance in HCC pathogenesis and treatment responses, highlighting their underpinning molecular pathways in HCC initiation and progression. Similarly, the biological importance and clinical application of miRNAs in HCC are summarized.

Value of Serum miRNA-96-5p and miRNA-99a-5p as Diagnostic Biomarkers for Hepatocellular Carcinoma

Purpose

Circulatory microRNAs (miRNAs) have the potential to be employed as markers for cancer detection and as prognostic tools for disease management. As a result, our goal was to explore the effectiveness of serum miRNA-96-5p and miRNA-99a-5p as diagnostic tools in hepatocellular carcinoma (HCC).

Patients and methods

Blood samples were collected from 55 patients with HCV-induced HCC, 55 patients with HCV-induced liver cirrhosis, and 55 healthy controls. The expression levels of miRNA-96-5p and miRNA-99a-5p were measured using quantitative RT-PCR.

Results

miRNA-96-5p expression levels were increased in HCC patient sera, while miRNA-99a-5p levels were reduced. According to ROC curve analysis, using a combination of circulating miRNA-96-5p, miRNA-99a-5-, and alpha-fetoprotein (AFP) improves the accuracy of diagnoses for HCC, with an area under the curve (AUC) of 0.97, compared to AUCs of 0.82, 0.86, and 0.73, respectively, for the individual biomarkers. Furthermore, the present data suggested that higher serum miRNA-96-5p levels were linked to larger tumors and metastasis, whereas lower serum miRNA-99a-5p levels were exclusively linked to HCC metastasis.

Conclusion

Using miRNA-96-5p and miRNA-99a-5p in combination with AFP increased both sensitivity and specificity for the diagnosis of HCC. Furthermore, serum levels were linked to tumor size and metastasis. These findings suggested that serum miRNA-96-5p and miRNA-99a-5p could be used as non-invasive biomarkers for the diagnosis of HCC.

Potential role of microRNAs in selective hepatic insulin resistance: From paradox to the paradigm

The paradoxical action of insulin on hepatic glucose metabolism and lipid metabolism in the insulin-resistant state has been of much research interest in recent years. Generally, insulin resistance would promote hepatic gluconeogenesis and demote hepatic de novo lipogenesis. The underlying major drivers of these mechanisms were insulin-dependent, via FOXO-1-mediated gluconeogenesis and SREBP1c-mediated lipogenesis. However, insulin-resistant mouse models have shown high glucose levels as well as excess lipid accumulation. As suggested, the inert insulin resistance causes the activation of the FOXO-1 pathway promoting gluconeogenesis. However, it does not affect the SREBP1c pathway; therefore, cells continue de novo lipogenesis. Many hypotheses were suggested for this paradoxical action occurring in insulin-resistant rodent models. A "downstream branch point" in the insulin-mediated pathway was suggested to act differentially on the FOXO-1 and SREBP1c pathways. MicroRNAs have been widely studied for their action of pathway mediation via suppressing the intermediate protein expressions. Many in vitro studies have postulated the roles of hepato-specific expressions of miRNAs on insulin cascade. Thus, miRNA would play a pivotal role in selective hepatic insulin resistance. As observed, there were confirmations and contradictions between the outcomes of gene knockout studies conducted on selective hepatic insulin resistance and hepato-specific miRNA expression studies. Furthermore, these studies had evaluated only the effect of miRNAs on glucose metabolism and few on hepatic de novo lipogenesis, limiting the ability to conclude their role in selective hepatic insulin resistance. Future studies conducted on the role of miRNAs on selective hepatic insulin resistance warrant the understanding of this paradoxical action of insulin.

MiR-155 promotes cadmium-induced autophagy in rat hepatocytes by suppressing Rheb expression

Cadmium is an environmental pollutant that threatens the health of both humans and animals. Current studies have shown that while hepatotoxic damage induced by cadmium is closely related to autophagy, its intrinsic mechanism has not been elucidated. MicroRNA plays a regulatory role on different stages of autophagy. In this study, we investigated the mechanisms by which microRNA-155 (miR-155) regulate cadmium-induced hepatotoxicity in rat hepatocytes (BRL 3A cells) and in vivo. We found that cadmium exposure could cause liver injury in rats, resulting in a decreased liver index, increased alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) activity, hepatocyte steatosis, and ultrastructure damage. Cadmium exposure also induced autophagy in hepatocytes, resulting in increased expression of ATG5, Belin1, LC3II, and an increased number of autophagosomes. In addition, cadmium exposure upregulated miR-155 expression, downregulated Rheb mRNA expression, and downregulated the level of protein expression in the Rheb/mTOR signaling pathway in rat hepatocytes. The overexpression of miR-155 followed by cadmium exposure upregulated the level of autophagy in BRL3A cells, whereas miR-155 inhibition had the opposite effect. In addition, miR-155 negatively regulated Rheb. A dual-luciferase reporter assay verified the negative regulatory effect of miR-155 on Rheb targeting. Knockdown of Rheb downregulated cadmium-induced autophagy. Therefore, the Rheb/mTOR signaling can negatively regulate autophagy. The present study demonstrates that miR-155 promotes cadmium-induced autophagy in rat hepatocytes by suppressing Rheb expression.

MicroRNAs as Diagnostic Tools in Hepatocellular Carcinoma

Liver cancer is the fourth leading cause of cancer-related deaths worldwide, with hepatocellular carcinoma (HCC) accounting for approximately 80% of all liver cancers. The serum concentration of alpha-fetoprotein (AFP) is the only validated biomarker for HCC diagnosis. MicroRNAs (miRNAs) are small non-coding RNAs of 21–30 nucleotides playing a critical role in human carcinogenesis, with types of miRNAs with oncogenic (oncomiRs) or tumor suppressor features. The altered expression of miRNAs in HCC is associated with many pathological processes, such as cancer initiation, tumor growth, apoptosis escape, promotion of migration and invasion. Moreover, circulating miRNAs have been increasingly investigated as non-invasive biomarkers for HCC diagnosis. MiRNAs’ expression patterns are altered in HCC and several single miRNAs or miRNAs panels have been found significantly up or downregulated in HCC with respect to healthy controls or non-oncological patients (cirrhotic or with viral hepatitis). However, any of the investigated miRNAs or miRNAs panels has entered clinical practice so far. This has mostly to do with lack of protocols standardization, small sample size and discrepancies in the measurement techniques. This review summarizes the major findings regarding the diagnostic role of miRNAs in HCC and their possible use together with standard biomarkers in order to obtain an early diagnosis and easier differential diagnosis from non-cancerous liver disease.

MicroRNA-199: A Potential Therapeutic Tool for Hepatocellular Carcinoma in an Experimental Model

Hepatocellular carcinoma is one of the major health problems throughout the world with a very poor prognosis. MicroRNAs are small regulatory non-protein-coding RNA molecules. We aimed at investigating microRNA-199 as a potential therapeutic tool for HCC both in vitro and in an experimental model. A therapeutic strategy based on the effect of microRNAs to target genes responsible for liver cancer was adopted in this work. The ability of these small RNAs to potently influence cellular behavior was also investigated. The role of miR-199a in the development of liver cancer has been identified using a systematic literature search using miRBase. HepG2 cell line was used to test the effect of miRNA199a in vitro. Hepatocellular carcinoma was induced in Male Balb/C mice by diethylnitrosamine (DEN). Mice were treated with miRNA-199a and sacrificed after 16 weeks and blood samples and liver specimens were collected for biochemical and histopathological assessment. Histopathological examination of liver specimens after miRNA 199a treatment showed regression of Hepatocellular carcinoma with restoration of normal architecture. AFP, VEGF and TNFα levels decreased after treatment with miRNA 199a. Caspase 3 and 9; showed decreased expression in animals treated with miRNA 199a than non-treated ones.

Recent advances in bionanomaterials for liver cancer diagnosis and treatment

According to the World Health Organization, liver cancer is the fourth leading cause of cancer associated with death worldwide. It demands effective treatment and diagnostic strategies to hinder its recurrence, complexities, aggressive metastasis and late diagnosis. With recent progress in nanotechnology, several nanoparticle-based diagnostic and therapeutic modalities have entered into clinical trials. With further developments in nanoparticle mediated liver cancer diagnosis and treatment, the approach holds promise for improved clinical liver cancer management. In this review, we discuss the key advances in nanoparticles that have potential for liver cancer diagnosis and treatment. We also discuss the potential of nanoparticles to overcome the limitations of existing therapeutic modalities.

Transcription Factors and Methylation Drive Prognostic miRNA Dysregulation in Hepatocellular Carcinoma

Many dysregulated microRNAs (miRNAs) have been suggested to serve as oncogenes or tumor suppressors to act as diagnostic and prognostic factors for HCC patients. However, the dysregulated mechanisms of miRNAs in HCC remain largely unknown. Herein, we firstly identify 114 disordered mature miRNAs in HCC, 93 of them are caused by dysregulated transcription factors, and 10 of them are driven by the DNA methylation of their promoter regions. Secondly, we find that seven up-regulated miRNAs (miR-9-5p, miR-452-5p, miR-452-3p, miR-1180-3p, miR-4746-5p, miR-3677-3 and miR-4661-5p) can promote tumorigenesis via inhibiting multiple tumor suppressor genes participated in metabolism, which may act as oncogenes, and seven down-regulated miRNAs (miR-99-5p, miR-5589-5p, miR-5589-3p, miR-139-5p, miR-139-3p, miR-101-3p and miR-125b-5p) can suppress abnormal cell proliferation via suppressing a number of oncogenes involved in cancer-related pathways, which may serve as tumor suppressors. Thirdly, our findings reveal a mechanism that transcription factor and miRNA interplay can form various regulatory loops to synergistically control the occurrence and development of HCC. Finally, our results demonstrate that this key transcription factor FOXO1 can activate a certain number of tumor suppressor miRNAs to improve the survival of HCC patients, suggesting FOXO1 as an effective therapeutic target for HCC patients. Overall, our study not only reveals the dysregulated mechanisms of miRNAs in HCC, but provides several novel prognostic biomarkers and potential therapeutic targets for HCC patients.

MicroRNA-99a-5p suppresses cell proliferation, migration, and invasion by targeting isoprenylcysteine carboxylmethyltransferase in oral squamous cell carcinoma

BACKGROUND

MicroRNA (miR)-99a-5p acts as a tumor suppressor in several tumors, including bladder cancer and breast cancer, but its biological function in oral squamous cell carcinoma (OSCC) is poorly understood.

METHODS

miR-99a-5p expression was determined in OSCC tissues and cell lines using quantitative reverse transcription polymerase chain reaction (RT-qPCR). Cell proliferation was assessed by the Cell Counting Kit-8 assay and colony formation assay. Wound healing and Transwell assays were used to analyze migration and invasion abilities, respectively, in OSCC cells. The luciferase reporter assay, RT-qPCR, and western blotting were used to determine the relationship between miR-99a-5p and isoprenylcysteine carboxylmethyltransferase (ICMT).

RESULTS

miR-99a-5p expression in OSCC tissues and cell lines was significantly decreased compared with corresponding controls, and was significantly associated with clinical stage and lymph node metastasis in OSCC. Functional assays revealed that miR-99a-5p overexpression significantly inhibited the proliferation, migration, and invasion abilities of CAL-27 and TCA-8113 OSCC cells. miR-99a-5p was found to directly target ICMT, while ICMT restoration reversed the role of miR-99a-5p in OSCC cells.

CONCLUSIONS

Our results indicate that miR-99a-5p-mediates the down-regulation of ICMT, which could be used as a novel potential therapeutic target for OSCC treatment.

MicroRNAs: Regulators of immunological reactions in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the third prominent cause of cancer mortality, with increasing prevalence and poor survival worldwide. Being diagnosed at an advanced stage, HCC frequently results in poor prognosis, treatment failure, and recurrence. Post-treatment reactivation and recurrence often amplify the immunosuppressed state induced by HCC pathogenesis. Therefore, stimulating the immune system may be a potential therapy measure for the treatment of HCC. Immune responses of the body may be potentiated by modulation of various effector cells such as B-cells, T-cells, Treg cells, natural killer cells, dendritic cells, cytotoxic T-lymphocytes, and other antigen-presenting cells. microRNAs (small non-coding RNAs) are the regulators of gene expression via translational inhibition or mRNA degradation. Various activities and developmental stages of the immune system are governed by miRNAs and they have a regulative impact on innate and adaptive immune cells in both, healthy and diseased conditions. Their misexpression has been associated with the initiation, development, and metastasis of various cancer types, including HCC. This review summarizes the functional impact of these immuno-miRNAs in the improvement of tumor conditions.

MicroRNAs in the Pathogenesis of Hepatocellular Carcinoma: A Review

Simple Summary

Hepatocellular carcinoma (HCC) is one of the most frequently occurring cancers, and the prognosis for late-stage HCC remains poor. A better understanding of the pathogenesis of HCC is expected to improve outcomes. MicroRNAs (miRNAs) are small, noncoding, single-stranded RNAs that regulate the expression of various target genes, including those in cancer-associated genomic regions or fragile sites in various human cancers. We summarize the central roles of miRNAs in the pathogenesis of HCC and discuss their potential utility as valuable biomarkers and new therapeutic agents for HCC.

Abstract

Hepatocellular carcinoma (HCC) is the seventh most frequent cancer and the fourth leading cause of cancer mortality worldwide. Despite substantial advances in therapeutic strategies, the prognosis of late-stage HCC remains dismal because of the high recurrence rate. A better understanding of the etiology of HCC is therefore necessary to improve outcomes. MicroRNAs (miRNAs) are small, endogenous, noncoding, single-stranded RNAs that modulate the expression of their target genes at the posttranscriptional and translational levels. Aberrant expression of miRNAs has frequently been detected in cancer-associated genomic regions or fragile sites in various human cancers and has been observed in both HCC cells and tissues. The precise patterns of aberrant miRNA expression differ depending on disease etiology, including various causes of hepatocarcinogenesis, such as viral hepatitis, alcoholic liver disease, or nonalcoholic steatohepatitis. However, little is known about the underlying mechanisms and the association of miRNAs with the pathogenesis of HCC of various etiologies. In the present review, we summarize the key mechanisms of miRNAs in the pathogenesis of HCC and emphasize their potential utility as valuable diagnostic and prognostic biomarkers, as well as innovative therapeutic targets, in HCC diagnosis and treatment.

Emerging neuroprotective strategies for the treatment of ischemic stroke: An overview of clinical and preclinical studies

Stroke is the leading cause of disability and thesecond leading cause of death worldwide. With the global population aged 65 and over growing faster than all other age groups, the incidence of stroke is also increasing. In addition, there is a shift in the overall stroke burden towards younger age groups, particularly in low and middle-income countries. Stroke in most cases is caused due to an abrupt blockage of an artery (ischemic stroke), but in some instances stroke may be caused due to bleeding into brain tissue when a blood vessel ruptures (hemorrhagic stroke). Although treatment options for stroke are still limited, with the advancement in recanalization therapy using both pharmacological and mechanical thrombolysis some progress has been made in helping patients recover from ischemic stroke. However, there is still a substantial need for the development of therapeutic agents for neuroprotection in acute ischemic stroke to protect the brain from damage prior to and during recanalization, extend the therapeutic time window for intervention and further improve functional outcome. The current review has assessed the past challenges in developing neuroprotective strategies, evaluated the recent advances in clinical trials, discussed the recent initiative by the National Institute of Neurological Disorders and Stroke in USA for the search of novel neuroprotectants (Stroke Preclinical Assessment Network, SPAN) and identified emerging neuroprotectants being currently evaluated in preclinical studies. The underlying molecular mechanism of each of the neuroprotective strategies have also been summarized, which could assist in the development of future strategies for combinational therapy in stroke treatment.

Circulating miR-99a-5p Expression in Plasma: A Potential Biomarker for Early Diagnosis of Breast Cancer

MicroRNAs have emerged as new diagnostic and therapeutic biomarkers for breast cancer. Herein, we analysed miR-99a-5p expression levels in primary tumours and plasma of breast cancer patients to evaluate its usefulness as a minimally invasive diagnostic biomarker. MiR-99a-5p expression levels were determined by quantitative real-time PCR in three independent cohorts of patients: (I) Discovery cohort: breast cancer tissues (n = 103) and healthy breast tissues (n = 26); (II) Testing cohort: plasma samples from 105 patients and 98 healthy donors; (III) Validation cohort: plasma samples from 89 patients and 85 healthy donors. Our results demonstrated that miR-99a-5p was significantly downregulated in breast cancer tissues compared to healthy breast tissues. Conversely, miR-99a-5p levels were significantly higher in breast cancer patients than in healthy controls in plasma samples from both testing and validation cohorts, and ROC curve analysis revealed that miR-99a-5p has good diagnostic potential even to detect early breast cancer. In conclusion, miR-99a-5p’s deregulated expression distinguished healthy patients from breast cancer patients in two different types of samples (tissues and plasma). Interestingly, expression levels in plasma were significantly lower in healthy controls than in early-stage breast cancer patients. Our findings suggest circulating miR-99a-5p as a novel promising non-invasive biomarker for breast cancer detection.

Vitamin D3 mediates miR-15a-5p inhibition of liver cancer cell proliferation via targeting E2F3

Vitamin D3 has been demonstrated to suppress the development and progression of liver cancer, but the mechanism is unclear. The effects of vitamin D3 and microRNA (miR)-15a-5p on liver cancer cells were investigated in the present study using MTT and colony formation assays, flow cytometry, western blotting and reverse transcription-quantitative PCR. A dual-luciferase reporter assay was performed to determine whether E2F transcription factor 3 (E2F3) was a target of miR-15a-5p. The effects of silencing the E2F3 gene expression in liver cancer cells were investigated using a small interfering RNA. Vitamin D3 suppressed liver cancer cell proliferation, induced apoptosis and increased miR-15a-5p expression. Treatment with the miR-15a-5p mimics significantly suppressed liver cancer cell proliferation compared with that of the controls. Bioinformatics analysis and a dual-luciferase reporter assay demonstrated that E2F3 was a target of miR-15a-5p and that silencing E2F3 inhibited liver cancer cell proliferation. Therefore, Vitamin D3 suppressed cell proliferation by miR-15a-5p-mediated silencing of E2F3 gene expression. These findings suggested a role for vitamin D3 and E2F3 targeting as potential novel liver cancer therapies.

Identification of key microRNAs involved in tumorigenesis and prognostic microRNAs in breast cancer

Breast cancer is a commonly diagnosed cancer in women, and one of the leading causes of cancer-related death among female patients However, the key microRNAs involved in its tumorigenesis and microRNAs of prognostic values have not been fully understood. In the present study, we aimed to perform a systematic analysis of microRNA expression profiles to identify some key microRNAs associated with tumor initiation and prognosis. Using TCGA breast cancer datasets, we identified 110 differentially expressed microRNAs. The functional enrichment analysis of the upregulated microRNAs revealed signaling transduction pathways, such as Notch and Wnt signaling pathway, and metabolism-related pathways such as sugar and nucleotide sugar metabolism, and oxidative stress response. Moreover, multivariable Cox model based on three variables of hsa-mir-130a, hsa-mir-3677, and hsa-mir-1247 stratified patients into high-risk and low-risk groups, which showed significant prognostic difference. In addition, we also tested the performance of this model in patient cohorts of any specific breast cancer subtypes or different TNM stages. The high performance in risk prediction was also observed in all of breast cancer subtypes and TNM stages. We also observed that there were highly possible interactions between hsa-mir-130a and seven target genes. Among these target genes, VAV3 and ESR1 were predicted as the target genes of hsa-mir-130a, suggesting that hsa-mir-130a may function by regulating the expression of VAV3 and ESR1 in breast cancer. In conclusion, the stratification based on the multivariable Cox model showed high performance in risk prediction. The dysregulated microRNAs and prognostic microRNAs greatly improved our understanding of the microRNA-related molecular mechanism underlying breast cancer.

Role of MicroRNA in the Diagnosis and Management of Hepatocellular Carcinoma

INTRODUCTION

Hepatocellular Carcinoma (HCC) is one of the most common malignant tumors in the world and comes third in cancer-induced mortality. The need for improved and more specific diagnostic methods that can detect early-stage disease is immense, as it is amenable to curative modalities, while advanced HCC is associated with low survival rates. microRNA (miRNA) expression is deregulated in HCC and this can be implemented both diagnostically and therapeutically.

OBJECTIVE

To provide a concise review on the role of miRNA in diagnosis, prognosis, and treatment of HCC.

METHODS

We conducted a comprehensive review of the PubMed bibliographic database.

RESULTS

Multiple miRNAs are involved in the pathogenesis of HCC. Measurement of the levels of these miRNAs either in tumor tissue or in the blood constitutes a promising diagnostic, as well as prognostic tool. OncomiRs are miRNAs that promote tumorigenesis, thus inhibiting them by administering antagomiRs is a promising treatment option. Moreover, replacement of the depleted miRNAs is another potential therapeutic approach for HCC. Modification of miRNA levels may also regulate sensitivity to chemotherapeutic agents.

CONCLUSION

miRNA play a pivotal role in HCC pathogenesis and once the underlying mechanisms are elucidated, they will become part of everyday clinical practice against HCC.

MicroRNAs in Animal Models of HCC

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related mortality. Molecular heterogeneity and absence of biomarkers for patient allocation to the best therapeutic option contribute to poor prognosis of advanced stages. Aberrant microRNA (miRNA) expression is associated with HCC development and progression and influences drug resistance. Therefore, miRNAs have been assayed as putative biomarkers and therapeutic targets. miRNA-based therapeutic approaches demonstrated safety profiles and antitumor efficacy in HCC animal models; nevertheless, caution should be used when transferring preclinical findings to the clinics, due to possible molecular inconsistency between animal models and the heterogeneous pattern of the human disease. In this context, models with defined genetic and molecular backgrounds might help to identify novel therapeutic options for specific HCC subgroups. In this review, we describe rodent models of HCC, emphasizing their representativeness with the human pathology and their usefulness as preclinical tools for assessing miRNA-based therapeutic strategies.

MicroRNA delivery through nanoparticles

MicroRNAs (miRNAs) are attracting a growing interest in the scientific community due to their central role in the etiology of major diseases. On the other hand, nanoparticle carriers offer unprecedented opportunities for cell specific controlled delivery of miRNAs for therapeutic purposes. This review critically discusses the use of nanoparticles for the delivery of miRNA-based therapeutics in the treatment of cancer and neurodegenerative disorders and for tissue regeneration. A fresh perspective is presented on the design and characterization of nanocarriers to accelerate translation from basic research to clinical application of miRNA-nanoparticles. Main challenges in the engineering of miRNA-loaded nanoparticles are discussed, and key application examples are highlighted to underline their therapeutic potential for effective and personalized medicine.

Role of regulatory miRNAs of the PI3K/AKT/mTOR signaling in the pathogenesis of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the common malignant human tumors with high morbidity worldwide. Aberrant activation of the oncogenic phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) signaling is related to clinicopathological features of HCC. Emerging data revealed that microRNAs (miRNAs) have prominent implications for regulating cellular proliferation, differentiation, apoptosis, and metabolism through targeting the PI3K/AKT/mTOR signaling axis. The recognition of the crucial role of miRNAs in hepatocarcinogenesis represents a promising area to identify novel anticancer therapeutics for HCC. The present study summarizes the major findings about the regulatory role of miRNAs in the PI3K/AKT/mTOR pathway in the pathogenesis of HCC.

miR‑5191 functions as a tumor suppressor by targeting RPS6KB1 in colorectal cancer

MicroRNAs (miRNAs/miRs) are a class of small non‑coding RNAs that play pivotal roles in cancer physiology as important epigenetic regulators of gene expression. Several miRNAs have been previously discovered that regulate the proliferation of the colorectal cancer (CRC) cell line HCT116. In the present study, one of these miRNAs, miR‑5191, was characterized as a tumor suppressor in CRC cells. Transfection with miR‑5191 led to a significant decrease in cell proliferation, invasiveness, tumor sphere‑forming ability and tumor organoid growth, as determined via trypan blue, Transwell, sphere culture and organoid culture assays, respectively. Flow cytometric analyses revealed that miR‑5191 induced the cell cycle arrest and apoptosis of CRC cells. Additionally, the expression of miR‑5191 was downregulated in CRC tumor tissues compared with in normal tissues, as measured by reverse transcription‑quantitative PCR analysis. Ribosomal protein S6 kinase β1 (RPS6KB1) was identified as a direct target of miR‑5191. Ectopic expression of RPS6KB1 suppressed the function of miR‑5191. Intratumoral injection of miR‑5191 mimic suppressed tumor growth in HCT116 xenografts. These findings suggested a novel tumor‑suppressive function for miR‑5191 in CRC, and its potential applicability for the development of anticancer miRNA therapeutics.

miR-155, miR-96 and miR-99a as potential diagnostic and prognostic tools for the clinical management of hepatocellular carcinoma

Increasing evidence has demonstrated that circulating microRNAs (miRNAs) can be utilized as potential biomarkers for the diagnosis of cancer, as well as a prognostic tool for the management of the disease. Therefore, the present study aimed to evaluate the predictive ability of miRNA (miR)-155, miR-96 and miR-99a for the diagnosis and prognosis of hepatocellular carcinoma (HCC). Tissues were collected from 30 patients with HCC and their matched adjacent normal liver tissues, as well as from serum samples from 30 patients with HCC and 30 healthy controls. Reverse transcription-quantitative PCR was used to measure the expression levels of miR-155, miR-96 and miR-99a. The expression levels of miR-155 and miR-96 were upregulated in the tissues and serum of patients with HCC, whereas miR-99a expression levels were decreased. Receiver operating characteristics (ROC) curve analysis revealed that circulating miR-155, miR-96, miR-99a and a combination of these three miRNAs could serve as diagnostic biomarkers for HCC with areas under the curve (AUC) of 0.84, 0.824, 0.799 and 0.931, respectively. Serum α-fetoprotein (AFP) was detected using electrochemiluminescence immunoassay analyzer. The addition of AFP with the combination of these three miRNAs offered a higher accuracy of HCC diagnosis (AUC, 0.979; sensitivity, 90.0%; specificity, 100.0%). In addition, elevated expression levels of miR-155 and miR-96 were associated with poor survival time of patients with HCC. The panel of miR-155, miR-96, miR-99a and AFP had a higher sensitivity and specificity for the diagnosis of HCC when compared with a single marker. Furthermore, the present data suggested that miR-155 and miR-96 may be potential prognostic markers for the clinical management of patients with HCC.

Emerging roles of microRNAs in regulating the mTOR signaling pathway during tumorigenesis

The mammalian target of rapamycin (mTOR) is a large Ser/Thr protein kinase that belongs to the phosphoinositide 3-kinase (PI3K) family and mediates various physiological and pathological processes, especially cell proliferation, protein synthesis, autophagy, and cancer development. The mTOR expression is transient and tightly regulated in normal cells, but it is overactivated in cancer cells. Recently, several studies have indicated that microRNAs (miRNAs) play a critical role in the regulation of mTOR and mTOR-associated processes, some acting as inhibitors and the others as activators. Although it is still in infancy, the strategy of combining both miRNAs and mTOR inhibitors might provide an approach to selectively sensitizing tumor cells to chemotherapy-induced DNA damage and subsequently attenuating the tumor cell growth and apoptosis.

Molecular Comparison of Imatinib-Naïve and Resistant Gastrointestinal Stromal Tumors: Differentially Expressed microRNAs and mRNAs

Despite the success of imatinib in advanced gastrointestinal stromal tumor (GIST) patients, 50% of the patients experience resistance within two years of treatment underscoring the need to get better insight into the mechanisms conferring imatinib resistance. Here the microRNA and mRNA expression profiles in primary (imatinib-naïve) and imatinib-resistant GIST were examined. Fifty-three GIST samples harboring primary KIT mutations (exon 9; n = 11/exon 11; n = 41/exon 17; n = 1) and comprising imatinib-naïve (IM-n) (n = 33) and imatinib-resistant (IM-r) (n = 20) tumors, were analyzed. The microRNA expression profiles were determined and from a subset (IM-n, n = 14; IM-r, n = 15) the mRNA expression profile was established. Ingenuity pathway analyses were used to unravel biochemical pathways and gene networks in IM-r GIST. Thirty-five differentially expressed miRNAs between IM-n and IM-r GIST samples were identified. Additionally, miRNAs distinguished IM-r samples with and without secondary KIT mutations. Furthermore 352 aberrantly expressed genes were found in IM-r samples. Pathway and network analyses revealed an association of differentially expressed genes with cell cycle progression and cellular proliferation, thereby implicating genes and pathways involved in imatinib resistance in GIST. Differentially expressed miRNAs and mRNAs between IM-n and IM-r GIST were identified. Bioinformatic analyses provided insight into the genes and biochemical pathways involved in imatinib-resistance and highlighted key genes that may be putative treatment targets.

The roles and mechanism of IFIT5 in bladder cancer epithelial-mesenchymal transition and progression

The prognosis of bladder cancer (BCa) depends on several key factors including anatomical site, tumor grade, and stage. In general, muscle-invasive bladder cancer (MIBC) is associated with higher incidence of distant metastasis compared with Non-muscle-invasive bladder cancer (NMIBC). Treatment outcome of the patients with metastatic BCa has been very poor with ~15% of overall survival rate. Thus, it is apparently important to understand the underlying biology for metastatic progression of BCa. Although epithelial–mesenchymal transition (EMT) has long been implicated in BCa metastasis and treatment resistance, the underlying mechanism is not fully understood. In this study, we have identified that the expression of interferon induced protein with tetratricopeptide repeats 5 (IFIT5) is positively correlated with pathological characteristics, and predicts a poor prognosis of BCa patients. Since the function of IFIT5 in BCa has not yet been characterized, we demonstrate that IFIT5 can induce EMT, promote cell migration and invasion, and increase the expression of ICAM1 in BCa via down-regulation of mature miR-99a. Moreover, ICAM1 is shown as a direct target of miR-99a. Overall, we conclude that IFIT5 is a new oncogene in BCa.

Tumor suppressor function of miR-129-5p in lung cancer

Lung cancer causes severe health problems worldwide and, in China, besides being the principal cause of mortality among urbanites, it is the second leading cause of mortality in the rural population, preceded by hepatocellular carcinoma. Between 80 and 85% of lung cancer is classified as non-small cell lung cancer (NSCLC). The high mobility group box 1 (HMGB1) protein serves an important function in the tumor microenvironment and antitumor response, and may be targeted by microRNA (miR). In the present study, miR-129-5p was identified to target HMGB1 and miR-129-5p exhibited low expression levels in NSCLC tissues. Overexpression of miR-129-5p inhibited cell proliferation and promoted cell apoptosis. In conclusion, the results of the present study suggested the inhibitory function of miR-129-5p and revealed a novel therapeutic target for further investigation.

Targeting the mTOR regulatory network in hepatocellular carcinoma: Are we making headway?

The mechanistic target of rapamycin (mTOR) pathway coordinates organismal growth and homeostasis in response to growth factors, nutrients, and cellular energy stage. The pathway regulates several major cellular processes and is implicated in various pathological conditions, including hepatocellular carcinoma (HCC). This review summarizes recent advances of the mTOR pathway, highlights the potential of the mTOR pathway as a therapeutic target, and explores clinical trials targeting the mTOR pathway in HCC. Although the review focuses on the mTOR pathway involved in HCC, more comprehensive discussions (eg, developing a rational design for future trials targeting the mTOR pathway) are also applicable to other tumors.

Diagnostic and prognostic value of serum miR-99a expression in oral squamous cell carcinoma

BACKGROUND

Despite progress in the treatment of oral squamous cell carcinoma (OSCC) over past years, the prognosis for OSCC patients remains dismal. MicroRNA-99a (miR-99a) has been found to involve in the development of many cancer types, but its clinical role in OSCC is unclear.

OBJECTIVE

The aim of this study was to explore the clinical implications of serum miR-99a in OSCC.

METHODS

This study detected serum miR-99a levels in 121 OSCC cases and 55 healthy controls by using quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis.

RESULTS

The data showed that serum miR-99a expression was significantly decreased in OSCC patients compared with normal controls. OSCC patients with low miR-99a expression experienced more frequent poor differentiation and advanced clinical stage. Furthermore, in screening OSCC cases from normal controls, miR-99a could yield a receiver-operating characteristic (ROC) area under the curve (AUC) of 0.911 with 83.6% specificity and 80.2% sensitivity. Notably, patients with high miR-99a expression had longer overall survival and recurrence free survival. Finally, serum miR-99a was identified to be an independent prognostic indicator for OSCC.

CONCLUSIONS

These results suggested that miR-99a might be a valuable marker for the prediction of early detection and prognosis in OSCC.

The heterogeneity of plasma miRNA profiles in hepatocellular carcinoma patients and the exploration of diagnostic circulating miRNAs for hepatocellular carcinoma

Heterogeneity is prevalent in cancer both between and within individuals. Although a few studies have identified several circulating microRNAs (miRNAs) for cancer diagnosis, the complete plasma miRNA profile for hepatocellular carcinoma (HCC) remains undefined, and whether the plasma miRNA profiles are heterogeneous is unknown. Here, we obtained individualized plasma miRNA profiles of both healthy subjects and HCC patients via genome-wide deep sequencing. Compared with the highly stable miRNA profile of the healthy subjects, the profile of the HCC patients was highly variable. Seven miRNAs were optimized as potential plasma-based biomarkers for HCC diagnosis. Combined with the clinical data of The Cancer Genome Atlas (TCGA) cohort, three out of the seven miRNAs were correlated with the survival of the HCC patients. To investigate the effect of cancer cells on the plasma miRNAs profile, we compared the most differentially expressed miRNAs between plasma and tissues. Furthermore, miRNAseq data of HCC patients from TCGA were recruited for comparisons. We found that the differences between plasma and tissue were inconsistent, suggesting that other cells in addition to cancer cells also contribute to plasma miRNAs. Using two HCC cancer cell lines, we examined the levels of seven differentially expressed miRNAs. The reverse direction of certain miRNAs alterations between cancer cells and media further confirmed that miRNAs may be selectively pump out by cancer cells.

Proliferation of Cells with Severe Nuclear Deformation on a Micropillar Array

Cellular responses on a topographic surface are fundamental topics about interfaces and biology. Herein, a poly(lactide- co-glycolide) (PLGA) micropillar array was prepared and found to trigger significant self-deformation of cell nuclei. The time-dependent cell viability and thus cell proliferation was investigated. Despite significant nuclear deformation, all of the examined cell types (Hela, HepG2, MC3T3-E1, and NIH3T3) could survive and proliferate on the micropillar array yet exhibited different proliferation abilities. Compared to the corresponding groups on the smooth surface, the cell proliferation abilities on the micropillar array were decreased for Hela and MC3T3-E1 cells and did not change significantly for HepG2 and NIH3T3 cells. We also found that whether the proliferation ability changed was related to whether the nuclear sizes decreased in the micropillar array, and thus the size deformation of cell nuclei should, besides shape deformation, be taken into consideration in studies of cells on topological surfaces.

Non-viral nanocarriers for intracellular delivery of microRNA therapeutics

MicroRNAs are small regulatory noncoding RNAs that regulate various biological processes. Herein, we will present the development of the strategies for intracellular miRNAs delivery, and specially focus on the rational designed routes, their mechanisms of action, as well as potential therapeutics used in the host cells orin vivostudies.