Aberrant concentrations of liver-derived plasma albumin mRNA in liver pathologies

Lower Serum Albumin Level: A Prospective Risk Predictor of Hepatocellular Carcinoma in Patients With Chronic Hepatitis B Virus Infection

Hepatocellular carcinoma (HCC) is one of the most common malignant tumours in China, at high annual incidence and mortality. Chronic hepatitis B virus infection (CHB) is considered as a leading cause to bring about HCC in China. Serum albumin (ALB) level has been adopted to verify its risk with HCC development as a combination variable with other factors. However, the predictive value of a single ALB level on HBV-related HCC risk remained unclear. The aim of this study was to evaluate the prediction ability of serum ALB concentration on the risk of HBV-related HCC development. A prospectively enrolled clinical cohort compromising 2932 cases of CHB patients with at least 1-year exclusion window was selected to explore the predictive role of serum ALB level on incident HCC risk. Baseline clinical data including host characters and laboratory test were collected at the initial period of hospitalisation. The hazard ratio of ALB level associated with HCC development was assessed by Cox proportional hazards regression model using univariate and multivariate analyses. We evaluated the discrimination accuracy of ALB level in predicting HCC development by receiver operating characteristic (ROC) curves. Dose-dependent and time-dependent effects of ALB level on HCC risk prediction were demonstrated, respectively, using a restricted cubic spline and a Fine and Grey competing risk model. Referred to patients with higher ALB level, those with lower ALB level exhibited significantly increased risk of HCC development after adjustment for host variables (dichotomised analyses: hazard ratio = 3.12, 95% confidence interval 1.63-5.97, p = 8.23 × 10-4, plog-rank = 5.97 × 10-4; tertile analyses: hazard ratio = 2.07, 95% confidence interval 1.63-2.64, p = 3.77 × 10-9, plog-rank < 2.00 × 10-16; quartile analyses: hazard ratio = 2.10, 95% confidence interval 1.56-2.84, p = 9.87 × 10-7, plog-rank < 2.00 × 10-16). There was a statistically increasing trend on HCC risk which was found following by the decrease of ALB level (ptrend < 0.0001). Similar findings were present by the Kaplan-Meier analysis, cumulative incidences of HCC development were significantly higher in patients with lower ALB levels, with the p value obtained from log-rank test were all < 0.0001. The result of dose-dependent effect showed hazard ratio (HR) value of HCC risk was gradually decreasing as the increasing of ALB level, with non-linear correlation being statistically significant (Wald χ2 = 20.59, p = 0.000). HR value in lower ALB level remained persistently prominent by fluctuating around 2.73 in the whole follow-up time by adjusting for host variables. Sub-cohort analysis by ROC revealed that the discrimination ability of the ALB model was performed better than Child-Pugh (C-P) model in both cohort of patients with 1-year (area under curve [AUC] 0.762 vs. 0.720) and 2-year exclusion window (AUC 0.768 vs. 0.728). The AUC added by ALB level was demonstrated significantly from host model to full model. Lower ALB level was significantly associated with an increased risk of HBV-related HCC and could provide extra useful clinical utility to other host features, which might be a promising non-invasive indicator for surveillance on HCC development.

A review on cell-free RNA profiling: Insights into metabolic diseases and predictive value for bariatric surgery outcomes

BACKGROUND

The advent of liquid biopsies presents a novel, minimally invasive methodology for the detection of disease biomarkers, offering a significant advantage over traditional biopsy techniques. Particularly, the analysis of cell-free RNA (cfRNA) has garnered interest due to its dynamic expression profiles and the capability to study various RNA species, including messenger RNA (mRNA) and long non-coding RNA (lncRNA). These attributes position cfRNA as a versatile biomarker with broad potential applications in clinical research and diagnostics.

SCOPE OF REVIEW

This review delves into the utility of cfRNA biomarkers as prognostic tools for obesity-related comorbidities, such as diabetes, dyslipidemia, and non-alcoholic fatty liver disease.

MAJOR CONCLUSIONS

We evaluate the efficacy of cfRNA in forecasting metabolic outcomes associated with obesity and in identifying patients likely to experience favorable clinical outcomes following bariatric surgery. Additionally, this review synthesizes evidence from studies examining circulating cfRNA across different physiological and pathological states, with a focus on its role in diabetes, including disease progression monitoring and treatment efficacy assessment. Through this exploration, we underscore the emerging relevance of cfRNA signatures in the context of obesity and its comorbidities, setting the stage for future investigative efforts in this rapidly advancing domain.

Single Cell and Plasma RNA Sequencing for RNA Liquid Biopsy for Hepatocellular Carcinoma

BACKGROUND

Human plasma contains RNA transcripts released by multiple cell types within the body. Single-cell transcriptomic analysis allows the cellular origin of circulating RNA molecules to be elucidated at high resolution and has been successfully utilized in the pregnancy context. We explored the application of a similar approach to develop plasma RNA markers for cancer detection.

METHODS

Single-cell RNA sequencing was performed to decipher transcriptomic profiles of single cells from hepatocellular carcinoma (HCC) samples. Cell-type-specific transcripts were identified and used for deducing the cell-type-specific gene signature (CELSIG) scores of plasma RNA from patients with and without HCC.

RESULTS

Six major cell clusters were identified, including hepatocyte-like, cholangiocyte-like, myofibroblast, endothelial, lymphoid, and myeloid cell clusters based on 4 HCC tumor tissues as well as their paired adjacent nontumoral tissues. The CELSIG score of hepatocyte-like cells was significantly increased in preoperative plasma RNA samples of patients with HCC (n = 14) compared with non-HCC participants (n = 49). The CELSIG score of hepatocyte-like cells declined in plasma RNA samples of patients with HCC within 3 days after tumor resection. Compared with the discriminating power between patients with and without HCC using the abundance of ALB transcript in plasma [area under curve (AUC) 0.72)], an improved performance (AUC: 0.84) was observed using the CELSIG score. The hepatocyte-specific transcript markers in plasma RNA were further validated by ddPCR assays. The CELSIG scores of hepatocyte-like cell and cholangiocyte trended with patients' survival.

CONCLUSIONS

The combination of single-cell transcriptomic analysis and plasma RNA sequencing represents an approach for the development of new noninvasive cancer markers.

Profiling the circulating mRNA transcriptome in human liver disease

The human circulation contains cell-free DNA and non-coding microRNA (miRNA). Less is known about the presence of messenger RNA (mRNA). This report profiles the human circulating mRNA transcriptome in people with liver cirrhosis (LC) and hepatocellular carcinoma (HCC) to determine whether mRNA analytes can be used as biomarkers of liver disease. Using RNAseq and RT-qPCR, we investigate circulating mRNA in plasma from HCC and LC patients and demonstrate detection of transcripts representing more than 19,000 different protein coding genes. Remarkably, the circulating mRNA expression levels were similar from person to person over the 21 individuals whose samples were analyzed by RNAseq. Liver derived circulating transcripts such as albumin (ALB), apolipoprotein (APO) A1, A2 & H, serpin A1 & E1, ferritin light chain (FTL) and fibrinogen like 1 (FGL1) were significantly upregulated in HCC patient samples. Higher levels of some of these liver-specific transcripts in the plasma of HCC patients were confirmed by RT-qPCR in another cohort of 20 individuals. Several less abundant circulating transcripts associated with cancer were detected in most HCC samples, but not in healthy subjects. Liver specificity of circulating transcripts was confirmed by investigating their expression in HCC tumor and liver cancer cell lines. Liver specific mRNA sequences in the plasma were predominantly present outside circulating extracellular vesicles.

Conclusions: The circulating “mRNA” transcriptome is remarkably consistent in diversity and expression from person to person. Detection of transcripts corresponding to disease selective polypeptides suggests the possibility that circulating mRNA can work as a biomarker analyte for cancer detection.

High preoperative serum globulin in hepatocellular carcinoma is a risk factor for poor survival

Background: Serum globulin (GLB), albumin (ALB) and albumin/globulin ratio (AGR) have been reported as prognosis related factors for certain malignancies; however, the prognostic value of globulin (GLB) in hepatocellular carcinoma (HCC) has rarely been studied. This study was performed to evaluate whether GLB analysis could be applied for the prediction of the prognosis of patients received liver resection. Methods: A training cohort study involving 210 HCC patients undergoing curative liver resection between January 2007 and December 2012, and a validation cohort involving 100 HCC patients contemporaneously undergoing curative liver resection in another set were recruited. The survival curves were graphed and log-rank test was performed to analyze the differences between the curves. The cutoff value was selected by X-title program. Results: Univariate and multivariate analysis indicated that high serum GLB level is a risk factor for poor cancer-specific survival (CSS) (P < 0.05). Conversely, high ALB level is a prediction for favor CSS (P = 0.010). Conclusions: We identified the preoperative high GLB level as a prognostic risk factor for patients after treatment of liver cancer resection. This easily obtained variable may act as an available clinical biomarker to predict the prognosis of such patients.

Integrative single-cell and cell-free plasma RNA transcriptomics elucidates placental cellular dynamics

The human placenta is a dynamic and heterogeneous organ critical in the establishment of the fetomaternal interface and the maintenance of gestational well-being. It is also the major source of cell-free fetal nucleic acids in the maternal circulation. Placental dysfunction contributes to significant complications, such as preeclampsia, a potentially lethal hypertensive disorder during pregnancy. Previous studies have identified significant changes in the expression profiles of preeclamptic placentas using whole-tissue analysis. Moreover, studies have shown increased levels of targeted RNA transcripts, overall and placental contributions in maternal cell-free nucleic acids during pregnancy progression and gestational complications, but it remains infeasible to noninvasively delineate placental cellular dynamics and dysfunction at the cellular level using maternal cell-free nucleic acid analysis. In this study, we addressed this issue by first dissecting the cellular heterogeneity of the human placenta and defined individual cell-type-specific gene signatures by analyzing more than 24,000 nonmarker selected cells from full-term and early preeclamptic placentas using large-scale microfluidic single-cell transcriptomic technology. Our dataset identified diverse cellular subtypes in the human placenta and enabled reconstruction of the trophoblast differentiation trajectory. Through integrative analysis with maternal plasma cell-free RNA, we resolved the longitudinal cellular dynamics of hematopoietic and placental cells in pregnancy progression. Furthermore, we were able to noninvasively uncover the cellular dysfunction of extravillous trophoblasts in early preeclamptic placentas. Our work showed the potential of integrating transcriptomic information derived from single cells into the interpretation of cell-free plasma RNA, enabling the noninvasive elucidation of cellular dynamics in complex pathological conditions.

Albumin and apolipoprotein H mRNAs in human plasma as potential clinical biomarkers of liver injury: analyses of plasma liver-specific mRNAs in patients with liver injury

CONTEXT

Plasma liver-specific mRNAs are useful biomarkers of hepatotoxicity in rats.

OBJECTIVE

To investigate the potential application of liver-specific mRNAs as biomarkers for liver injury in humans.

METHODS

We determined the plasma levels of liver-specific mRNAs by real-time qRT-PCR in healthy donors and patients with liver injury.

RESULTS

Plasma levels of albumin (ALB) and apolipoprotein H (APOH) mRNAs increased in patients with elevated serum alanine aminotransferase. These mRNAs also increased in plasma after transcatheter arterial chemoembolization, which induces specific injury to liver.

CONCLUSIONS

We demonstrated the potential application of plasma ALB and APOH mRNAs as clinical biomarkers for liver injury.

Circulating RNA molecules as biomarkers in liver disease

Liver disease is a major cause of morbidity and mortality worldwide. As in other fields of medicine, there is a stringent need for non-invasive markers to improve patient diagnostics, monitoring and prognostic ability in liver pathology. Cell-free circulating RNA molecules have been recently acknowledged as an important source of potential medical biomarkers. However, many aspects related to the biology of these molecules remain to be elucidated. In this review, we summarize current concepts related to the origin, transportation and possible functions of cell-free RNA. We outline current development of extracellular RNA-based biomarkers in the main forms of non-inherited liver disease: chronic viral hepatitis, hepatocellular carcinoma, non-alcoholic fatty liver, hepato-toxicity, and liver transplantation. Despite recent technological advances, the lack of standardization in the assessment of these markers makes their adoption into clinical practice difficult. We thus finally review the main factors influencing quantification of circulating RNA. These factors should be considered in the reporting and interpretation of current findings, as well as in the proper planning of future studies, to improve reliability and reproducibility of results.

Comparison of circulating, hepatocyte specific messenger RNA and microRNA as biomarkers for chronic hepatitis B and C

Circulating microRNAs have been widely recognized as a novel category of biomarker in a variety of physiological and pathological conditions. Other reports revealed that fragments of organ specific messenger RNAs are also detectable in serum/plasma and can be utilized as sensitive indicators of liver pathology and cancer. In order to assess the sensitivity and reliability of these two class of RNAs as marker of hepatitis B or C induced chronic liver disease, we collected plasma samples from 156 chronic hepatitis B or C patients (HBV active n = 112, HBV carrier n = 19, hepatitis C n = 25) and 22 healthy donors and quantified their circulating mRNA for albumin, HP (haptoglobin), CYP2E1 (cytochrome P450, family 2, subfamily E) and ApoA2 (Apolipoprotein A2) in conjunction with microRNA-122, a well established marker for acute and chronic liver injury. We found that plasma microRNA-122 level is significantly elevated in patients with active HBV but not in HBV carriers. Furthermore, microRNA-122 is not elevated in HCV patients even though their median serum alanine aminotransferase (sALT) was three fold of the healthy donors. Nevertheless, circulating mRNAs, especially albumin mRNA, showed much more sensitivity in distinguishing active hepatitis B, hepatitis B carrier or HCV patientsfrom healthy control. Correlation and multiple linear regression analysis suggested that circulating mRNAs and miRNAs are much more related to HBsAg titre than to sALT. Immunoprecipitation of HBsAg in HBV patients’ plasma resulted in enrichment of albumin and HP mRNA suggesting that fragments of liver specific transcripts can be encapsidated into HBsAg particles. Taken together, our results suggest that hepatocyte specific transcripts in plasma like albumin mRNA showed greater sensitivity and specificity in differentiating HBV or HCV induced chronic liver disease than microRNA-122. Circulating mRNA fragments merit more attention in the quest of next generation biomarkers for various maladies.

Utilization of paramagnetic microparticles for automated isolation of free circulating mRNA as a new tool in prostate cancer diagnostics

Determination of serum mRNA gained a lot of attention in recent years, particularly from the perspective of disease markers. Streptavidin-modified paramagnetic particles (SMPs) seem an interesting technique, mainly due to possible automated isolation and high efficiency. The aim of this study was to optimize serum isolation protocol to reduce the consumption of chemicals and sample volume. The following factors were optimized: amounts of (i) paramagnetic particles, (ii) oligo(dT)20 probe, (iii) serum, and (iv) the binding sequence (SMPs, oligo(dT)20 , serum vs. oligo(dT)20 , serum and SMPs). RNA content was measured, and the expression of metallothionein-2A as possible prostate cancer marker was analyzed to demonstrate measurable RNA content with ability for RT-PCR detection. Isolation is possible on serum volume range (10-200 μL) without altering of efficiency or purity. Amount of SMPs can be reduced up to 5 μL, with optimal results within 10-30 μL SMPs. Volume of oligo(dT)20 does not affect efficiency, when used within 0.1-0.4 μL. This optimized protocol was also modified to fit needs of automated one-step single-tube analysis with identical efficiency compared to conventional setup. One-step analysis protocol is considered a promising simplification, making RNA isolation suitable for automatable process.

Identification of novel liver-specific mRNAs in plasma for biomarkers of drug-induced liver injury and quantitative evaluation in rats treated with various hepatotoxic compounds

Circulating liver-specific mRNAs such as albumin (Alb) and α-1-microglobulin/bikunin precursor (Ambp) have been reported to be potential biomarkers for drug-induced liver injury (DILI). We identified novel circulating liver-specific mRNAs and quantified them, together with the two previously reported mRNAs, in plasma from rats treated with various hepatotoxicants to validate circulating liver-specific mRNAs as biomarkers for DILI. Among six genes selected from the database, high liver specificity of apolipoprotein h (Apoh) and group-specific component (Gc) mRNAs were confirmed by reverse transcription (RT)-PCR and the copy numbers of these mRNAs elevated in plasma from rats treated with thioacetamide. Liver-specific mRNAs (Alb, Ambp, Apoh, and Gc) were quantified by real-time RT-PCR in plasma from rats with single dosing of seven hepatotoxicants. There were noticeable interindividual and intercompound variabilities in the severity of liver injury. The levels of four mRNAs increased almost in parallel and correlated with changes in the alanine aminotransferase (ALT) values and the hepatocellular necrosis scores at 24h after dosing. It was noteworthy that the magnitude of the increases in mRNA levels was greater than that in the ALT value. Time course analysis within 24h after dosing revealed that the timing of the increase was different among mRNA species, and the plasma levels of Alb and Gc mRNAs increased substantially earlier than the ALT values, suggesting that patterns of changes in circulating liver-specific mRNAs indicate the progression of liver injury. These results strongly support the reliability and usefulness of the four circulating liver-specific mRNAs as biomarkers for DILI.

Genetics and molecular biology in laboratory medicine, 1963-2013

The past 50 years have seen many changes in laboratory medicine, either as causes or consequences of increases in productivity and expansion of the range of information which can be provided. The drivers and facilitators of change in relation to clinical applications of molecular biology included the need for diagnostic tools for genetic diseases and technical advances such as PCR and sequencing. However, molecular biology techniques have proved to have far wider applications, from detection of infectious agents to molecular characterization of tumors. Journals such as Clinical Chemistry and Laboratory Medicine play an important role in communication of these advances to the laboratory medicine community and in publishing evaluations of their practical value.

Biomarkers in neonatology: the next generation of tests

Over the past two decades, neonatal clinicians have commonly used host response biomarkers to diagnose and assess the severity of systemic infection. Most of these biomarkers, such as acute-phase proteins or cytokines, are non-specific immunomodulating mediators of the inflammatory cascade. With advances in biochemical/genetic research, it is anticipated that future biomarkers will be 'organ and/or disease specific'. There is also the quest for discovery of 'novel' biomarkers to assist diagnosis and prognosis of neonatal diseases using powerful mass-screening techniques, e.g. the next-generation sequencing, proteomics and arrays. This article aims to introduce the concept of the next generation of biomarkers to practising neonatal clinicians, and, hopefully, to integrate basic science research into day-to-day clinical practice in the future.