The Diagnostic Value of MicroRNAs as a Biomarker for Hepatocellular Carcinoma: A Meta-Analysis

Circulating microRNAs as promising diagnostic biomarkers for hepatocellular carcinoma: a systematic review and meta-analysis

Introduction: Hepatocellular carcinoma (HCC), the most common type of liver cancer, is a major global health problem, ranking as the third leading cause of cancer-related death worldwide. Early identification and diagnosis of HCC requires the discovery of reliable biomarkers. Therefore, the study aimed to assess the diagnostic accuracy of miRNAs for HCC. The protocol was registered on PROSPERO website with the registration number CRD42023417494. Method: A literature search was conducted in PubMed, Scopus, Embase, Wiley Online Library, and Science Direct databases to identify pertinent articles published between 2018 and 30 July 2023. Stata 17.0 software was employed to determine the pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic ratio (DOR), and area under the curve (AUC) for evaluating the accuracy of miRNAs in diagnosing HCC. The assessment of heterogeneity among studies involved the use of the Cochran-Q test and I2 statistic tests. Due to the observed significant heterogeneity, the random-effect model was chosen. Subgroup analysis and meta-regression analysis were also undertaken to explore potential sources contributing to heterogeneity. Deeks' funnel plot was used to assess publication bias. In addition, Fagan's nomogram and likelihood ratio scattergram were utilized to assess the clinical validity of miRNAs for HCC. Result: Twenty-four articles were included, involving 1,668 individuals diagnosed with HCC and 1,236 healthy individuals. The findings revealed pooled sensitivity of 0.84 (95% CI: 0.80-0.88), specificity of 0.81 (95% CI: 0.77-0.84), PLR of 4.36 (95% CI: 3.59-5.30), NLR of 0.19 (95% CI: 0.15-0.25), DOR of 22.47 (95% CI: 14.47-32.64), and an AUC of 0.89 (95% CI: 0.86-0.91) for the diagnosis of HCC using miRNAs. Furthermore, results from the subgroup analysis demonstrated that superior diagnostic performance was observed when utilizing plasma miRNAs, a large sample size (≥100), and miRNA panels. Conclusion: Hence, circulating miRNAs demonstrate substantial diagnostic utility for HCC and can serve as effective non-invasive biomarkers for the condition. Additionally, miRNA panels, miRNAs derived from plasma, and miRNAs evaluated in larger sample sizes (≥100) demonstrate enhanced diagnostic efficacy for HCC diagnosis. Nevertheless, a large pool of prospective studies and multi-center research will be required to confirm our findings in the near future.

MicroRNAs as Plasma Biomarkers of Hepatocellular Carcinoma in Patients with Liver Cirrhosis-A Cross-Sectional Study

Ultrasound screening for hepatocellular carcinoma (HCC) in patients with liver cirrhosis has a poor sensitivity for small tumors. Circulating microRNAs (miRNAs) have been explored as HCC biomarkers, but results are diverging. Here, we evaluate if miRNAs up-regulated in HCC tissue can be detected in plasma and used as screening biomarkers for HCC. In this cross-sectional study, plasma, HCC tissue and surrounding non-tumorous liver tissue were collected from liver resections. Tissue miRNAs were identified and quantitated by RNA-sequencing analysis, and the fold-changes between HCC and surrounding liver tissue were calculated. The miRNAs up-regulated in HCCs were then re-analyzed in plasma from the same patients, and the miRNAs with the highest plasma levels were subsequently measured in plasma from an independent cohort of patients with cirrhosis or HCC. In tissues from 84 resected patients, RNA-sequencing detected 197 differentially expressed miRNAs, 40 of which had a raw count above 200 and were analyzed in plasma from the same cohort. Thirty-one miRNAs were selected for further analysis in 200 patients with HCC or cirrhosis. Of these, eleven miRNAs were significantly increased in HCC as compared to cirrhosis patients. Only miR-93-5p and miR-151a-3p were significantly associated with HCC, with an AUC of 0.662. In comparison, alpha-fetoprotein and des-gamma-carboxy prothrombin yielded an AUC of 0.816, which increased to 0.832 if miR-93-5p and miR-151a-3p were added. When including sex and age, the addition of miR-93-5p and miR-151a-3p did not further improve the AUC (from 0.910 to 0.911). In conclusion, micro-RNAs up-regulated in HCCs are detectable in plasma but have a poor performance as screening biomarkers of HCC.

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.

miR221 regulates TGF-β1-induced HSC activation through inhibiting autophagy by directly targeting LAMP2

Liver fibrosis is a serious threat to human life and health. Activated hepatic stellate cells (HSCs) play a key role in the occurrence and development of liver fibrosis. Studies have reported that microRNAs (miRNAs/miRs) are involved in the pathological process of fibrosis, as well as its relevance in clinical diagnosis. However, the role of miR221 in hepatic fibrosis remains controversial. Remarkably, transforming growth factor‑β (TGF‑β1) caused HSC dysfunction in autophagic activation, characterized by an increase in P62 aggregation and LC3II expression. The present study aimed to determine whether autophagy regulates hepatic fibrosis by mediating HSC activation and explore the potential targets leading to the sequence of events associated with miR221. The expression of miR221 was quantified in a liver fibrosis model in vivo and in vitro, and its specific target gene lysosome‑associated membrane glycoprotein 2 (LAMP2) was predicted by bioinformatics. The results showed that the expression levels of collagen‑I (COL‑I) and α‑smooth muscle actin (α‑SMA) were increased in miR221‑overexpressing LX2 cells, while the autophagy inducer rapamycin reversed the inhibition of autophagic flux induced by miR221. Additionally, the overexpression of LAMP2 could significantly inhibit TGF‑β1‑induced COL‑I and α‑SMA expression, which was similar to the effect of the miR221 inhibitor on the regulation of TGF‑β1‑induced HSC activation. These results indicated that miR221 may regulate TGF‑β1‑induced HSC activation through inhibiting autolysosome function by directly targeting LAMP2. The molecular mechanism of miR221 in regulating TGF‑β1‑induced HSC activation may provide novel insight into therapies to ameliorate the pathological progression of liver fibrosis.

Value of miR-21 levels as potential biomarkers in the early diagnosis of hepatocellular carcinoma：a meta-analysis

BACKGROUND

Many studies have reported that miR-21 levels are different between hepatocellular carcinoma (HCC) patients and healthy controls, which could be used as a potential diagnostic biomarker for HCC. However, the diagnostic value of miR-21 for HCC varied greatly in previous studies. Therefore, this meta-analysis aims to provide higher grade evidence to investigate the diagnostic value of miR-21 for HCC.

METHODS

The databases of PubMed, Embase, Web of Science, and Chinese databases (CNKI and VIP) were searched. The indices of miR-21 in the diagnosis of HCC were pooled using bivariate random-effect models. QUADAS-2 was used to evaluate the quality of included studies. All statistical analyses were performed by STATA (12.0) software.

RESULTS

Totally, 1589 subjects from 14 publications were included in this study. The pooled sensitivity, specificity, positive likelihood ratios (PLR), negative likelihood ratios (NLR), and area under the curve (AUC) were 0.83 (0.77-0.88), 0.80 (0.74-0.85), 4.12 (3.04-5.57), 0.21 (0.15-0.30), and 0.88 (0.85-0.91), respectively. Subgroup analysis showed that the AUC was higher in Non-China subgroup, qRT-PCR subgroup, and plasma subgroup than that in China subgroup, ddPCR subgroup, and serum subgroup, respectively. However, the AUC was not significantly different between the healthy control subgroup and chronic hepatitis control subgroup. Significant heterogeneity was found in this meta-analysis, while no evident publication bias was identified.

CONCLUSIONS

miR-21 is a valuable biomarker for the early diagnosis of HCC.

Functional roles of non-coding RNAs regulated by thyroid hormones in liver cancer

Recent reports have shown the important role of the non-coding part of human genome RNA (ncRNA) in cancer formation and progression. Among several kinds of ncRNAs, microRNAs (miRNA) play a pivotal role in cancer biology. Accumulating researches have been focused on the importance of non-coding genes in various diseases. In addition to miRNAs, long non-coding RNAs (lncRNAs) have also been extensively documented. Recently, the study of human liver cancer has gradually shifted to these non-coding RNAs that were originally considered "junk". Notably, dysregulated ncRNAs maybe influence on cell proliferation, angiogenesis, anti-apoptosis, and metastasis. Thyroid hormones play critical roles in human development and abnormalities in thyroid hormone levels are associated with various diseases, such as liver cancer. Thyroid hormone receptors (TR) act as ligand-activated nuclear transcription factors to affect multiple functions through the gene-level regulation in the cells and several studies have revealed that thyroid hormone associated with ncRNAs expression. TR actions are complex and tissue- and time-specific, aberrant expression of the various TR isoforms have different effects and are associated with different types of tumor or stages of development. In this review, we discuss various aspects of the research on the thyroid hormones modulated ncRNAs to affect the functions of human liver cells.

Melatonin and regulation of miRNAs: novel targeted therapy for cancerous and noncancerous disease

miRNAs, small noncoding RNAs with crucial diagnostic and prognostic capabilities, play essential therapeutic roles in different human diseases. These biomarkers are involved in several biological mechanisms and are responsible for the regulation of multiple genes expressions in cells. miRNA-based therapy has shown a very bright future in the case of clinical interventions. Melatonin, the main product of the pineal gland, is a multifunctional neurohormone with numerous therapeutic potentials in human diseases. Melatonin is able to regulate miRNAs in different pathologies such as malignant and nonmalignant diseases, which can be considered as a novel kind of targeted therapy. Herein, this review discusses possible therapeutic utility of melatonin for the regulation of miRNAs in various pathological conditions.

Differentially expressed microRNAs in peripheral blood mononuclear cells of non-segmental vitiligo and their clinical significance

Background

Vitiligo is a frequent acquired depigmentation skin disease due to a loss of melanocytes. This study sought to characterize the expression pattern of microRNA (miRNA) in the peripheral blood mononuclear cells (PBMCs) of non‐segmental vitiligo (NSV) patients. We also screened for molecular markers that can be used to evaluate the clinical stages of NSV.

Methods

The miRNA expression profile in the PBMCs of four patients with progressive NSV and four healthy controls was determined using high‐throughput RNA sequencing. The divergently expressed miRNA was verified via qRT‐PCR in 26 progression, 26 stable NSV, and 26 healthy controls.

Results

Our findings posited that 323 miRNAs were differentially expressed in the PBMCs of NSV patients. The top 10 up‐regulated miRNAs in patients were hsa‐miR‐335‐5p, hsa‐miR‐20a‐5p, hsa‐miR‐514a‐3p, hsa‐miR‐144‐5p, hsa‐miR‐450b‐5p, hsa‐miR‐369‐3p, hsa‐miR‐101‐3p, hsa‐miR‐142‐5p, hsa‐miR‐19b‐3p, and hsa‐miR‐340‐5p. The top 10 down‐regulated miRNAs in patients were hsa‐miR‐4443, hsa‐miR‐1248, hsa‐miR‐6859‐3p, hsa‐miR‐668‐3p, hsa‐miR‐7704, hsa‐miR‐323a‐5p, hsa‐miR‐1237‐3p, hsa‐miR‐3127‐3p, hsa‐miR‐6735‐3p, and hsa‐miR‐127‐3p. The expressions of hsa‐miR‐20a‐5p in PBMCs of progressive and stable NSV were remarkably elevated relative to the healthy controls. In the characteristics curve analysis of hsa‐miR‐20a‐5p for differentiating progressive and stable NSV from normal subjects in PBMCs, the area under curve (AUC) was 0.92 and 0.81. Compared with patients in stable NSV, the hsa‐miR‐20a‐5p was markedly increased in PBMCs of progressive NSV patients, and the AUC was 0.81.

Conclusion

Our results showed that divergently expressed miRNAs contribute to the pathogenesis of NSV and that hsa‐miR‐20a‐5p can be applied as a biosignature for stage assessment in PBMCs of patients with NSV.

Emerging roles and potential clinical applications of noncoding RNAs in hepatocellular carcinoma

Hepatocellular carcinoma(HCC) is one of the most common forms of cancer, and accounts for a high proportion of cancer-associated deaths. Growing evidences have demonstrated that non- protein-coding regions of the genome could give rise to transcripts, termed noncoding RNA (ncRNA), that form novel functional layers of the cellular activity. ncRNAs are implicated in different molecular mechanisms and functions at transcriptional, translational and post-translational levels. An increasing number of studies have demonstrated a complex array of molecular and cellular functions of ncRNAs in different stages of the HCC tumorigenesis, either in an oncogenic or tumor-suppressive manner. As a result, several pre-clinical studies have highlighted the great potentials of ncRNAs as novel biomarkers for cancer diagnosis or therapeutics in targeting HCC progression. In this review, we briefly described the characteristics of several representative ncRNAs and summarized the latest findings of their roles and mechanisms in the development of HCC, in order to better understand the cancer biology and their potential clinical applications in this malignancy.