The role of microRNAs in the pathophysiology of adrenal tumors

MicroRNA regulation of adrenal glucocorticoid and androgen biosynthesis

Steroid hormones are derived from a common precursor molecule, cholesterol, and regulate a wide range of physiologic function including reproduction, salt balance, maintenance of secondary sexual characteristics, response to stress, neuronal function, and various metabolic processes. Among the steroids synthesized by the adrenal and gonadal tissues, adrenal mineralocorticoids, and glucocorticoids are essential for life. The process of steroidogenesis is regulated at multiple levels largely by transcriptional, posttranscriptional, translational, and posttranslational regulation of the steroidogenic enzymes (i.e., cytochrome P450s and hydroxysteroid dehydrogenases), cellular compartmentalization of the steroidogenic enzymes, and cholesterol processing and transport proteins. In recent years, small noncoding RNAs, termed microRNAs (miRNAs) have been recognized as major post-transcriptional regulators of gene expression with essential roles in numerous biological processes and disease pathologies. Although their role in the regulation of steroidogenesis is still emerging, several recent studies have contributed significantly to our understanding of the role miRNAs play in the regulation of the steroidogenic process. This chapter focuses on the recent developments in miRNA regulation of adrenal glucocorticoid and androgen production in humans and rodents.

Unraveling Therapeutic Opportunities and the Diagnostic Potential of microRNAs for Human Lung Cancer

Lung cancer is a major public health problem and a leading cause of cancer-related deaths worldwide. Despite advances in treatment options, the five-year survival rate for lung cancer patients remains low, emphasizing the urgent need for innovative diagnostic and therapeutic strategies. MicroRNAs (miRNAs) have emerged as potential biomarkers and therapeutic targets for lung cancer due to their crucial roles in regulating cell proliferation, differentiation, and apoptosis. For example, miR-34a and miR-150, once delivered to lung cancer via liposomes or nanoparticles, can inhibit tumor growth by downregulating critical cancer promoting genes. Conversely, miR-21 and miR-155, frequently overexpressed in lung cancer, are associated with increased cell proliferation, invasion, and chemotherapy resistance. In this review, we summarize the current knowledge of the roles of miRNAs in lung carcinogenesis, especially those induced by exposure to environmental pollutants, namely, arsenic and benzopyrene, which account for up to 1/10 of lung cancer cases. We then discuss the recent advances in miRNA-based cancer therapeutics and diagnostics. Such information will provide new insights into lung cancer pathogenesis and innovative diagnostic and therapeutic modalities based on miRNAs.

Multi-genomic analysis of 260 adrenocortical cancer patient tumors identifies novel network BIRC5-hsa-miR-335-5p-PAX8-AS1 strongly associated with poor survival

BACKGROUND

Adrenocortical carcinoma is a rare endocrine cancer with poor overall survival. Linking survival outcomes to a common target across multiple genomic datasets incorporating microRNA-long non-coding RNA dysregulation have not been well described. We hypothesized that a multi-database analysis of microRNA-long noncoding RNA-messenger RNA regulatory networks associated with survival will identify novel biomarkers.

METHODS

Significantly dysregulated genes or microRNA in adrenocortical carcinoma compared to normal adrenal was identified from sequencing data for 260 human adrenocortical carcinomas using GEO2R. The miRnet identified hub microRNA and genes and long noncoding RNA and microRNA associated with survival genes. The R2 generated Kaplan-Meier curves. The database miRTarBase linked genes associated with poor survival and dysregulated microRNA.

RESULTS

Analysis of genes and microRNAs differentially regulated in >50% of datasets revealed 75 genes and 12 microRNAs were upregulated, and 167 genes and 12 microRNAs were downregulated (bonf. P < .05). Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed cell cycle, P53 signaling, arachidonic acid and innate immune response, and PI3/Akt are altered in adrenocortical carcinoma. A microRNA-target interaction network of differentially regulated microRNAs identified upregulated miRNA107, 103a-3p and 27a-3p, 16-5p, and downregulated 335-5p to have the highest degree of interaction with upregulated (ie, TPX2, CDK1, BIRC5, PRC1, CCNB1, GINS1) and downregulated (ie, RSPO3, NR2F1, TLR4, HOXA5, USP53, SLC16A9) hub genes as well as hub long noncoding RNAs XIST, NEAT1, KCNQ1OT1, and PAX8-AS1. Survival analysis revealed that the hub genes are associated with poor overall survival (P < .05) of adrenocortical carcinoma in the Cancer Genome Atlas data.

CONCLUSION

A messenger RNA-microRNA-long noncoding RNA network analysis identified the BIRC5-miR335-5p-PAX8-AS1 network as one that was associated with poor overall survival in adrenocortical carcinoma, warranting further validation as a potential therapeutic target.

Identification of prognostic factors for predicting survival of patients with malignant adrenal tumors: A population-based study

Background

This study aimed to identify the prognostic factors for overall survival (OS) and cancer-specific survival (CSS) in patients with malignant adrenal tumors and establish a predictive nomogram for patient survival.

Methods

The clinical characteristics of patients diagnosed with malignant adrenal tumors between 1988 and 2015 were retrieved from the Surveillance, Epidemiology and End Results (SEER) database. As the external validation set, we included 110 real-world patients from our medical centers. Univariate and multivariate Cox regressions were implemented to determine the prognostic factors of patients. The results from Cox regression were applied to establish the nomogram.

Results

A total of 2,206 eligible patients were included in our study. Patients were randomly assigned to the training set (1,544; 70%) and the validation set (662; 30%). It was determined that gender, age, marital status, histological type, tumor size, SEER stage, surgery, and chemotherapy were prognostic factors that affected patient survival. The OS prediction nomogram contained all the risk factors, while gender was excluded in the CSS prediction nomogram. The receiver operating characteristic (ROC) curve and decision curve analysis (DCA) indicated that the nomogram had a better predictive performance than SEER stage. Moreover, the clinical impact curve (CIC) showed that the nomograms functioned as effective predictive models in clinical application. The C-index of nomogram for OS and CSS prediction was 0.773 (95% confidence interval [CI]: 0.761–0.785) and 0.689 (95% CI: 0.675–0.703) in the training set. The calibration curves exhibited significant agreement between the nomogram and actual observation. Additionally, the results from the external validation set also presented that established nomograms functioned well in predicting the survival of patients with malignant adrenal tumors.

Conclusions

The following clinical variables were identified as prognostic factors: age, marital status, histological type, tumor size, SEER stage, surgery, and chemotherapy. The nomogram for patients with malignant adrenal tumors contained the accurate predictive performance of OS and CSS, contributing to optimizing individualized clinical treatments.

Heterogeneous circulating miRNA profiles of PBMAH

OBJECTIVE

Primary bilateral macronodular adrenal hyperplasia (PBMAH), a rare cause of Cushing syndrome, is often diagnosed as a bilateral adrenal incidentaloma with subclinical cortisol production. Circulating microRNAs (miRNAs) are a characteristic of adrenocortical adenomas, but miRNA expression in PBMAH has not been investigated. We aimed to evaluate the circulating miRNA expression in patients with PBMAH and compare them with those in patients with non-functioning adrenocortical adenoma (NFA) and cortisol-producing adrenocortical adenoma (CPA).

METHODS

miRNA profiling of plasma samples from four, five, and five patients with NFA, CPA, and PBMAH, respectively, was performed. Selected miRNA expressions were validated using quantitative RT-PCR.

RESULTS

PBMAH samples showed distinct miRNA expression signatures on hierarchical clustering while NFA and CPA samples were separately clustered. PBMAH was distinguished from the adenoma group of NFA and CPA by 135 differentially expressed miRNAs. Hsa-miR-1180-3p, hsa-miR-4732-5p, and hsa-let-7b-5p were differentially expressed between PBMAH and adenoma (P = 0.019, 0.006, and 0.003, respectively). Furthermore, PBMAH could be classified into two subtypes based on miRNA profiling: subtype 1 with a similar profile to those of adenoma and subtype 2 with a distinct profile. Hsa-miR-631, hsa-miR-513b-5p, hsa-miR-6805-5p, and hsa-miR-548av-5p/548k were differentially expressed between PBMAH subtype 2 and adenoma (P = 0.027, 0.027, 0.027, and 1.53E-04, respectively), but not between PBMAH, as a whole, and adenoma.

CONCLUSION

Circulating miRNA signature was identified specific for PBMAH. The existence of subtype-based miRNA profiles may be associated with the pathophysiological heterogeneity of PBMAH.

The Diagnostic, Prognostic and Therapeutic Role of miRNAs in Adrenocortical Carcinoma: A Systematic Review

Adrenocortical carcinoma (ACC) is a rare endocrine malignancy with a dismal prognosis and a high rate of recurrence and mortality. Therapeutic options are limited. In some cases, the distinction of ACCs from benign adrenal neoplasms with the existing widely available pathological and histopathological tools is difficult. Thus, new biomarkers have been tested. We conducted a review of the recent literature on the advances of the diagnostic, prognostic and therapeutic role of miRNAs on ACC patients. More than 10 miRNAs validated by multiple studies were found to present a diagnostic and prognostic role for ACC patients, from which miR-483-5p and miR-195 were the most frequently met biomarkers. In particular, upregulation of miR-483-5p and downregulation of miR-195 were the most commonly validated molecular alterations. Unfortunately, data on the therapeutic role of miRNA are still scarce and limited mainly at the experimental level. Thus, the role of miRNA regulation in ACC remains an area of active research.

A Critical Appraisal of Contemporary and Novel Biomarkers in Pheochromocytomas and Adrenocortical Tumors

Simple Summary

Pheochromocytomas/paragangliomas (PPGLs) and adrenocortical tumors are neoplasms that originate from different regions of the adrenal gland and display significant heterogeneity with respect to their biological and clinical behavior. They may be sporadic or develop in the context of hereditary syndromes. Adrenocortical tumors are mostly benign but less than 2% are carcinomas associated with a poor outcome when diagnosed in advanced disease. The majority of PPGLS are benign, but a subset may develop metastatic disease. In particular, for PPGLs, it is mandatory to identify biomarkers of high sensitivity and specificity that lead to accurate diagnosis and predict patients with a malignant potential that would benefit from aggressive surveillance and administration of early treatment. Current biomarkers include mostly histopathological and genetic parameters but none of them can be considered independent predictive factors. Recent genomic studies have implemented new molecular biomarkers of high accuracy for the diagnosis and management of PPGLs and adrenocortical tumors. In this review, we summarize the current and novel biomarkers that may be considered valuable tools for diagnosis and prediction of malignancy in patients with PPGLs and adrenocortical tumors.

Abstract

Pheochromocytomas/Paragangliomas (PPGLs) and adrenocortical tumors are rare neoplasms with significant heterogeneity in their biologic and clinical behavior. Current diagnostic and predictive biomarkers include hormone secretion, as well as histopathological and genetic features. PPGL diagnosis is based on biochemical measurement of catecholamines/metanephrines, while histopathological scoring systems have been proposed to predict the risk of malignancy. Adrenocortical tumors are mostly benign, but some can be malignant. Currently, the stage of disease at diagnosis and tumor grade, appear to be the most powerful prognostic factors. However, recent genomic and proteomic studies have identified new genetic and circulating biomarkers, including genes, immunohistochemical markers and micro-RNAs that display high specificity and sensitivity as diagnostic or prognostic tools. In addition, new molecular classifications have been proposed that divide adrenal tumors in distinct subgroups with different clinical outcomes.

Identifying functioning and nonfunctioning adrenal tumors based on blood serum surface-enhanced Raman spectroscopy

Adrenal tumors are common tumors in urology and they can be further divided into functioning and nonfunctioning tumors according to whether there is uncommon endocrine function. In clinical practice, the early identification and accurate assessment of adrenal tumors are essential for the guidance of subsequent treatment. However, a nonfunctioning adrenal tumor often lacks obvious clinical symptoms, making it difficult to be timely and precisely diagnosed by conventional examinations. Therefore, a rapid and accurate method for identifying the functioning and nonfunctioning adrenal tumors is urgently required to achieve precise treatment of adrenal tumors. In this study, surface-enhanced Raman spectroscopy was investigated as a diagnostic tool to identify the blood serum samples from healthy volunteers as well as the patients with functioning and nonfunctioning adrenal tumors. Based on the SERS peak analysis, abnormal glycolysis, DNA/RNA, and amino acid metabolites were found to be potential biomarkers for identifying patients with adrenal tumors, while metabolites related to disordered protein catabolism and excessive hormone secretion were expected to further differentiate functioning adrenal tumors from nonfunctioning adrenal tumors. In addition, principal component analysis followed by support vector machine (PCA-SVM) was further applied on those serum SERS measurements, and the classification accuracies of 96.8% and 84.5% were achieved for differentiating healthy group versus adrenal tumor group and functioning adrenal tumor group versus nonfunctioning adrenal tumor group, respectively. The results have demonstrated the prodigious potential of precise adrenal tumor diagnosis by using the blood serum surface-enhanced Raman spectroscopy technique.

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

Background

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

Methods

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

Results

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

Conclusion

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

Genomics of benign adrenocortical tumors

Benign adrenocortical adenomas and hyperplasia are relatively common and include a spectrum of distinct entities, which diagnosis depends on the macroscopic aspect and the secretion profile. Recent advances in genomics have proposed high-throughput molecular characterization of adrenal tumors, thereby improving our knowledge on the pathophysiology and tumorigenesis of these tumors. Genomic (exome and chromosome alteration profiles), epigenomic (micro-RNAs expression and methylation profiles) and transcriptomic (gene expression profiles) studies highlighted the major roles of intracellular calcium signaling in aldosterone-producing adenomas (APA), of protein kinase A (PKA)/cAMP pathway in cortisol-producing tumors, and of Wnt/beta-catenin pathway in non-secreting tumors. Exome sequencing revealed new major drivers in all tumor types, including KCNJ5, ATP1A1, ATP2B3, CACNA1D and CACNA1H mutations in APA, PRKACA mutations in cortisol-producing adenomas (CPA) and ARMC5 mutations in primary macronodular adrenocortical hyperplasia (PMAH). The clinical impact of these findings is just starting to evolve. The identification of genetic syndromes, such as germline ARMC5 mutations in PMAH, has allowed genetic counseling. Key molecular alterations could serve as a basis for the development of targeted medical treatments for benign adrenal tumors. The recent developments in genomics, including single-cell technologies, and in proteomics and metabolomics will probably offer new perspectives for characterizing benign adrenal tumorigenesis.

Potential role of circulating microRNAs (486-5p, 497, 509-5p and 605) in metabolic syndrome Egyptian male patients

Objective: This study aims to evaluate the expression pattern of circulating microRNAs (miR)-486-5p, miR-497, miR-509-5p, and miR-605 in the serum of metabolic syndrome (MetS) Egyptian male patients. Methods: In this study, the circulating miR-486-5p, miR-497, miR509-5p, and miR-605 were amplified and quantitatively detected by quantitative real-time polymerase chain reaction in sera of 55 MetS male patients in comparison to 20 male controls. The level of fasting plasma glucose and triacylglycerol (TAG) were measured using calorimetric assay. Blood pressure was measured using mercuric sphygmomanometer. Anthropometric measurements were done to each individual. Furthermore, MetS patients were defined according to the criteria proposed by the American Heart Association and divided into three groups according to MetS index. Results: The study was performed on three groups and a control group defined as follows: group 1: 15 MetS patients who fulfilled all diagnostic criteria of MetS; group 2: 20 MetS patients with normal blood pressure; group 3: 20 MetS patients with normal TAG levels.The levels of miRs are expressed as [median (IQR)]. miR-486-5-p and miR-497 expression were elevated in group 1 [31.9(49), p˂0.0001; 73.1(42.5), p˂0.0001], group 2 [36.4(15.7), p˂0.0001; 68.3(54.8), p˂0.0001], and group (3) [10.8(18.9), p=0.0014; 27.5(39.7), p=0.0012]. MiR-509-5p was elevated in groups 1 and 2 [501(468), p=0.0001], [309(436), p=0.0006], respectively, while normally expressed in group 3 [0.93(0.077), p=0.0001]. miR-605 was elevated in groups 1 and 3 [25.4(20.0), p=0.0018], [54.8(65.8), p˂0.0001], while normally expressed in group 2 [0.84(0.67), p˂0.0001]. Conclusion: miRs (486-5p, 497, 509-5p, and 605) serum levels were higher in MetS patients than in healthy control subjects; therefore, these serum miRs can serve as early biomarkers and can be used to follow-up the prognosis of MetS.

The human adrenal cortex: growth control and disorders

This review summarizes key knowledge regarding the development, growth, and growth disorders of the adrenal cortex from a molecular perspective. The adrenal gland consists of two distinct regions: the cortex and the medulla. During embryological development and transition to the adult adrenal gland, the adrenal cortex acquires three different structural and functional zones. Significant progress has been made in understanding the signaling and molecules involved during adrenal cortex zonation. Equally significant is the knowledge obtained regarding the action of peptide factors involved in the maintenance of zonation of the adrenal cortex, such as peptides derived from proopiomelanocortin processing, adrenocorticotropin and N-terminal proopiomelanocortin. Findings regarding the development, maintenance and growth of the adrenal cortex and the molecular factors involved has improved the scientific understanding of disorders that affect adrenal cortex growth. Hypoplasia, hyperplasia and adrenocortical tumors, including adult and pediatric adrenocortical adenomas and carcinomas, are described together with findings regarding molecular and pathway alterations. Comprehensive genomic analyses of adrenocortical tumors have shown gene expression profiles associated with malignancy as well as methylation alterations and the involvement of miRNAs. These findings provide a new perspective on the diagnosis, therapeutic possibilities and prognosis of adrenocortical disorders.

MicroRNA 483-3p targets Pard3 to potentiate TGF-β1-induced cell migration, invasion, and epithelial-mesenchymal transition in anaplastic thyroid cancer cells

Anaplastic thyroid cancer (ATC) is associated with poor prognosis and is often untreatable. MicroRNA 483-3p (miR-483) and partitioning-defective 3 (Pard3), a member of the Pard family, have functions and regulatory mechanisms in ATC. The abnormal regulation of miR-483 may play an important role in tumorigenesis, and Par3 is known to regulate cell polarity, cell migration, and cell division. Tumor proliferation promoted by the regulation of miRNA expression can be regulated in thyroid cancer by upregulating transforming growth factor-β1 (TGF-β1), which is thought to interact with Pard3. When compared with adjacent non-tumor tissues, we found that miR-483 was upregulated and Pard3 was downregulated in 80 thyroid tumor samples. Disease-free survival was decreased when expression of miR-483 was upregulated and Pard3 expression was downregulated. Cell growth, migration, and invasion were induced by overexpression of miR-483. However, knockdown of miR-483 resulted in a loss of cell invasion and viability, both in vitro and in vivo. The expression of Pard3 was increased by the inhibition of miR-483, but TGF-β1-induced cell migration and invasion were decreased by miR-483 inhibition. A dual-luciferase reporter assay determined that Pard3 expression was downregulated when targeted with miR-483. The epithelial–mesenchymal transition (EMT), as well as Tiam1-Rac signaling, was induced by TGF-β1, which was decreased by the overexpression of Pard3. Pard3 decreased the inhibition of EMT and Tiam-Rac1 signaling, which resulted from transfection of ATC cells with miR-483. Overall, the results showed that downregulation of Pard3 resulted in increased cell invasion and EMT in ATC, which was promoted by treatment with miR-483. These findings suggest novel therapeutic targets and treatment strategies for this disease.

The next step: mechanisms driving adrenocortical carcinoma metastasis

Endocrine tumors have the peculiarity to become clinically evident not only due to symptoms related to space occupation by the growing lesion, similarly to most other tumors, but also, and most often, because of their specific hormonal secretion, which significantly contributes to their pathological burden. Malignant endocrine tumors, in addition, have the ability to produce distant metastases. Here, we critically review the current knowledge about mechanisms and biomarkers characterizing the metastatic process in adrenocortical carcinoma (ACC), a rare endocrine malignancy with a high risk of relapse and metastatization even when the primary tumor is diagnosed and surgically removed at an early stage. We highlight perspectives of future research in the domain and possible new therapeutic avenues based on targeting factors having an important role in the metastatic process of ACC.

Advances in understanding the molecular underpinnings of adrenocortical tumors

PURPOSE OF REVIEW

Adrenocortical tumors are divided into benign adenomas and malignant carcinomas. The former is relatively common and carries a favorable prognosis, whereas the latter is rare and frequently presents at an advanced stage, with poor outcomes. Advances in next-generation sequencing, genome analysis, and bioinformatics have allowed for high-throughput molecular characterization of adrenal tumorigenesis.

RECENT FINDINGS

Although recent genomic, epigenomic, and transcriptomic studies in large tumor cohorts have confirmed the central roles of aberrant Wnt/ß-catenin signaling, constitutive protein kinase A pathway activation, cell cycle dysregulation, and ion channelopathies in adrenal tumorigenesis, these studies also revealed novel signature events underlying malignant differentiation of adrenocortical carcinomas.

SUMMARY

Recent advances in understanding of the molecular mechanisms underlying adrenocortical tumorigenesis provide new molecular diagnostic and prognostic tools and opportunities for novel therapeutic approaches. These findings are particularly important in adrenocortical carcinoma, for which current treatment options are limited.

New insights in the clinical and translational relevance of miR483-5p in adrenocortical cancer

Adrenocortical cancer (ACC) is a rare aggressive malignancy. Recent ACC integrated genomics analysis contributed to redefine the risk groups on molecular basis, including tumor microRNAs (miRs), detectable also in the bloodstream. We developed a quantitative real-time (RT) assay for the measurement of miR483 and miR483-5p absolute levels in plasma samples. miR483/miR483-5p levels were evaluated in plasma samples of 27 patients with ACC before surgery and at follow-up.

Statistically significant differences in miR483-5p and miR483 levels were found between stage 1/2 and stage 3/4 ACCs in pre-surgery and post-surgery samples. ROC curve analysis of miR483–5p levels gave a prediction of the clinical stage (accuracy 0.917±0.084), with the best cut-off value of 0.221 ng/ml, prognosticating overall and recurrence-free survival. In a multivariate Cox analysis (HR 16.2, 95%CI[1.39-188.6, P<0.026]), miR483-5p was the only variable that significantly predicted recurrence, but not overall survival. In addition, miR483 and miR483-5p levels correlated with the number of circulating tumor cells (CTCs) detected in the same blood samples, independently of the timing of sampling. In conclusion, we demonstrated that miR483-5p absolute plasma levels in ACC patients are powerful molecular markers that may help in the follow-up of patients after surgery and chemotherapy, and contribute to more accurately classify and predict tumor progression.

miRNAs as potential therapeutic targets and diagnostic biomarkers for cardiovascular disease with a particular focus on WO2010091204

INTRODUCTION

A number of miRNAs have been reported to be critically involved in the regulation of cardiovascular disease (CVDs). Therefore, the development of potent analogues/inhibitors for miRNAs have thus become a key focus in the present drug discovery. In this review, we discuss the basic research and clinical use of miRNAs as the early diagnosis and therapeutic targets for CVD. We have also focused on the efficiency of therapeutically targeting miR-499, which is considered as one of the most promising molecules for treating CVDs. Areas covered: In this review, we have discussed the patents and patent applications related to miRNAs detected in CVD patients published in recent years. This review also covers the expression pattern of miR-499, as well as it highlights functions of its inhibitors in CVD. We used Google and Pubmed search engines to find relevant patents. Expert opinion: Although a massive number of miRNAs are patented as CVD biomarkers, further work is absolutely required to evaluate the reliable diagnostic values and therapeutic potential of these candidates. Overall, targeting miRNAs is definitely a promising strategy to be investigated for diagnosis and treatment of CVDs in future, however, the delivery system and off-targets effects are still a difficult challenge need to be elucidated.

ADRENOCORTICAL CARCINOMA: IN THE SEARCH FOR A PRE-OPERATIVE BIOMARKER

Adrenocortical tumors (ACT) are common malignancies of the cortex adrenal gland frequently non-functioning and benign. Differently, adrenocortical carcinoma (ACC) is a very rare neoplasia with an incidence of 0.7-2.0 cases per million people and an aggressive behaviour. Moreover ACC shows a poor prognosis with an estimated survival of 16-38%. Only surgery and the use of mitotane (sometime associated to standard chemotherapy) can represent a useful tool to fight against this malignancy, nonetheless ACC often metastasizes and recurs, decreasing considerably patient survival prospect. In the search of new potential tools to combat cancer, in the latest years omics works extended our knowledge on the ACC pathogenesis and made possible the investigation of novel ACC biomarkers. In this field of research, epigenetic studies identified a common signature in ACC, where the most altered miRNA found in ACC (miR-483-5p) seems now to represent a concrete biomarker to be used in the pre-operative diagnosis of ACC. A larger patient cohort is necessary to confirm this pivotal data: collaboration between scientific communities will be the key to determine the success of this fundamental discovery.