Liver stiffness measurement in the risk assessment of hepatocellular carcinoma for patients with chronic hepatitis

Matrix stiffening facilitates stemness of liver cancer stem cells by YAP activation and BMF inhibition

Matrix stiffening is one of the major risk factors for hepatocellular carcinoma (HCC) and drives tumor progression. The extracellular matrix (ECM) stiffness of HCC displays mechanical heterogeneity, with stiffness increasing from the core to the invasive frontier. The distribution of liver cancer stem cells (CSCs) is related to this mechanical property. However, it is not sufficiently understood how heterogeneous matrix stiffness regulates the stemness of CSCs. In this study, we developed an adjustable gelatin/alginate hydrogel to investigate the effect of various matrix stiffnesses on CSC stemness under three-dimensional culture conditions. Gelatin/alginate hydrogel with the stiffness of soft (5 kPa), medium (16 kPa), and stiff (81 kPa) were prepared by altering the concentration of calcium ions. It was found that a stiffer matrix promoted stemness-associated gene expression, reduced drug sensitivity, enhanced sphere-forming and clonogenic ability, and tumorigenic potential. Mechanistically, matrix stiffening facilitates CSC stemness by increasing Yes-associated protein (YAP) activity and inhibiting Bcl-2 modifying factor (BMF) expression. Knockdown of YAP or overexpression of BMF significantly attenuated matrix stiffening-induced stemness, suggesting the involvement of YAP and BMF in this process. Together, our results unravel the regulatory mechanism of heterogeneous matrix stiffness on CSC stemness and also provide a novel therapeutic strategy for eradicating CSCs and improving the efficiency of HCC treatment.

Investigating the Role of Extracellular Matrix Stiffness in Modulating the Ferroptosis Process in Hepatocellular Carcinoma Cells via Scanning Electrochemical Microscopy

Extracellular matrix (ECM) stiffness modulates a variety of cellular processes, including ferroptosis, a process with significant potential implications for hepatocellular carcinoma (HCC) fibrosis and cirrhosis. However, the exact relationship between ECM stiffness and HCC ferroptosis is yet unclarified, partially due to the lack of in situ information on key parameters of the ferroptosis process of living HCC cells. This study pioneers the use of in vitro mechanical microenvironment models of HCC and the scanning electrochemical microscopy (SECM) technique for understanding this interplay. We first cultured HuH7 cells on 4.0, 18.0, and 44.0 kPa polyacrylamide (PA) gels to simulate early, intermediate, and advanced HCC ECM stiffness, respectively. Then, we used SECM to in situ monitor changes in cell membrane permeability, respiratory activity, and reactive oxygen species (ROS) levels of erastin-induced HuH7 cells on PA gels, finding that increasing ECM stiffness potentiates ferroptosis, including increased membrane permeabilization and H2O2 release as well as reduced respiratory activity. Through further transcriptome sequencing and molecular biology measurements, we identified a critical role for focal adhesion kinase (FAK)-mediated yes-associated protein (YAP) in regulating the ferroptosis process dependent on ECM stiffness, which provides novel insights into the mechanical regulation of ferroptosis in HCC cells and may pave the way for innovative therapeutic strategies.

Matrix Stiffness Potentiates Stemness of Liver Cancer Stem Cells Possibly via the Yes-Associated Protein Signal

A hepatocellular carcinoma tissue has mechanical heterogeneity, where the stiffness gradually increases from the core to the invasion front. Furthermore, there is evidence that stem cells from liver cancer (LCSCs) preferentially enrich the invasion front, exhibiting the stiffest modulus in the tumor. LCSCs have the features of stem/progenitor cells and play a vital part in liver cancer development. However, whether matrix stiffness affects LCSC stemness remains unclear. Here, we established a three-dimensional hydrogel for culturing LCSCs to simulate the stiffness of the core and the invasion front of a liver cancer tissue. The results showed that a stiffer matrix (72.2 ± 0.90 kPa) significantly potentiated LCSC stemness as compared with a soft matrix (7.7 ± 0.41 kPa). Moreover, Yes-associated protein signaling might mediate this promotion. Together, our findings illustrate the relationship between matrix stiffness and LCSC stemness, which may aid the production of novel treatment approaches against liver cancer.

Sorafenib use in hepatitis B virus- or hepatitis C virus-related hepatocellular carcinoma: A propensity score matching study

Sorafenib is the recommended first-line treatment option for patients with advanced hepatocellular carcinoma (HCC). Hepatitis C virus (HCV)-related advanced HCC (HCV-HCC) seemed to have a better response than hepatitis B virus (HBV)-related HCC (HBV-HCC) in sorafenib use, but it was undetermined. Hence, we aimed to investigate the effect of sorafenib between HBV-HCC and HCV-HCC patients in Taiwan. From August 2012 to December 2016, 575 consecutive advanced HCC patients received sorafenib under the reimbursement of Taiwan national health insurance in our hospital. Radiologic assessment was performed at a 2-month interval. Those patients with tumor progression or liver function deterioration were disallowed for further sorafenib use. Patients with HBV or HCV infection were, retrospectively, enrolled and followed till December 2018. There were 277 (62.4%) HBV-HCC patients and 167 (37.6%) HCV-HCC patients. Before sorafenib, 192 (69.3%) HBV-HCC patients who had used nucleoside analogs (NAs) for HBV management, whereas only 5 (3%) HCV-HCC patients received interferon-based antiviral therapy. Overall survival (OS) of HCV-HCC patients was significantly superior to HBV-HCC patients without NAs (8.8 months vs. 4.9 months, p = 0.006), but was noninferior to HBV-HCC patients with NAs (8.8 months vs. 10.7 months, p = 0.54). Using propensity score matching, progression-free survival (2.0 months vs. 2.1 months, p = 0.374) and OS (10.5 months vs. 9.6 months, p = 0.746) between HBV-HCC and HCV-HCC groups were not different. Antiviral therapy might increase survival benefits of advanced HBV-HCC patients underwent sorafenib use, leading to a comparable OS to HCV-HCC patients in Taiwan.

Noninvasive Assessment of Hepatitis C Virus Infected Patients Using Vibration-Controlled Transient Elastography

Chronic infection with hepatitis C virus (HCV) is one of the leading causes of cirrhosis and hepatocellular carcinoma (HCC). Surveillance of these patients is an essential strategy in the prevention chain, including in the pre/post-antiviral treatment states. Ultrasound elastography techniques are emerging as key methods in the assessment of liver diseases, with a number of advantages such as their rapid, noninvasive, and cost-effective characters. The present paper critically reviews the performance of vibration-controlled transient elastography (VCTE) in the assessment of HCV patients. VCTE measures liver stiffness (LS) and the ultrasonic attenuation through the embedded controlled attenuation parameter (CAP), providing the clinician with a tool for assessing fibrosis, cirrhosis, and steatosis in a noninvasive manner. Moreover, standardized LS values enable proper staging of the underlying fibrosis, leading to an accurate identification of a subset of HCV patients that present a high risk for complications. In addition, VCTE is a valuable technique in evaluating liver fibrosis prior to HCV therapy. However, its applicability in monitoring fibrosis regression after HCV eradication is currently limited and further studies should focus on extending the boundaries of VCTE in this context. From a different perspective, VCTE may be effective in identifying clinically significant portal hypertension (CSPH). An emerging prospect of clinical significance that warrants further study is the identification of esophageal varices. Our opinion is that the advantages of VCTE currently outweigh those of other surveillance methods.

Noninvasive markers of liver steatosis and fibrosis after liver transplantation - Where do we stand?

In the last two decades, advances in immunosuppressive regimens have led to fewer complications of acute rejection crisis and consequently improved short-term graft and patient survival. In parallel with this great success, long-term post-transplantation complications have become a focus of interest of doctors engaged in transplant medicine. Metabolic syndrome (MetS) and its individual components, namely, obesity, dyslipidemia, diabetes, and hypertension, often develop in the post-transplant setting and are associated with immuno-suppressive therapy. Nonalcoholic fatty liver disease (NAFLD) is closely related to MetS and its individual components and is the liver manifestation of MetS. Therefore, it is not surprising that MetS and its individual components are associated with recurrent or "de novo" NAFLD after liver transplantation (LT). Fibrosis of the graft is one of the main determinants of overall morbidity and mortality in the post-LT period. In the assessment of post-LT steatosis and fibrosis, we have biochemical markers, imaging methods and liver biopsy. Because of the significant economic burden of post-LT steatosis and fibrosis and its potential consequences, there is an unmet need for noninvasive methods that are efficient and cost-effective. Biochemical scores can overestimate fibrosis and are not a good method for fibrosis evaluation in liver transplant recipients due to frequent post-LT thrombocytopenia. Transient elastography with controlled attenuation parameter is a promising noninvasive method for steatosis and fibrosis. In this review, we will specifically focus on the evaluation of steatosis and fibrosis in the post-LT setting in the context of de novo or recurrent NAFLD.

Non-invasive tests for the prediction of primary hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignancies in the world and it is one of the main complications of cirrhosis and portal hypertension. Even in the presence of a well-established follow-up protocol for cirrhotic patients, to date poor data are available on predictive markers for primary HCC occurrence in the setting of compensated advanced chronic liver disease patients (cACLD). The gold standard method to evaluate the prognosis of patients with cACLD, beyond liver fibrosis assessed with histology, is the measurement of the hepatic venous pressure gradient (HVPG). An HVPG ≥10 mmHg has been related to an increased risk of HCC in cACLD patients. However, these methods are burdened by additional costs and risks for patients and are mostly available only in referral centers. In the last decade increasing research has focused on the evaluation of several, simple, non-invasive tests (NITs) as predictors of HCC development. We reviewed the currently available literature on biochemical and ultrasound-based scores developed for the non-invasive evaluation of liver fibrosis and portal hypertension in predicting primary HCC. We found that the most reliable methods to assess HCC risk were the liver stiffness measurement, the aspartate aminotransferase to platelet ratio index score and the fibrosis-4 index. Other promising NITs need further investigations and validation for different liver disease aetiologies.

Liver stiffness as a predictor of hepatocellular carcinoma behavior in patients with hepatitis C related liver cirrhosis

BACKGROUND

Risk stratification and prognostication of hepatocellular carcinoma (HCC) help to improve patient outcome. Herein we investigated the role of liver stiffness measurement (LSM) in the prediction of HCC behavior.

METHODS

Totally 121 naïve patients with HCC were included. HCC radiological evaluation and staging were done. LSM was measured using virtual touch quantification. Patients were divided into early to intermediate HCC (BCLC-0, A and B) and late HCC (BCLCC and D). HCC was treated according to the BCLC stage. HCC recurrence-free interval was estimated.

RESULTS

The mean LSM inside the tumor was significantly lower than the peri-tumoral area and the cirrhotic non-cancerous liver parts (P < 0.001). In late HCCs stage, the mean LSM inside the tumor and in the peri-tumoral tissue was lower than the corresponding values in the early to intermediate HCCs stage (P < 0.001). LSM inside the tumor and in the peri-tumoral tissue negatively correlated with serum AFP, tumor vascular invasion, and stage (P < 0.05). The recurrence-free interval was directly correlated to LSM inside the tumor and inversely to LSM in cirrhotic non tumorous liver part. Kaplan-Meier analysis showed that the recurrence-free interval was significantly longer in patients with LSM inside the tumor of ≥1.25 m/s compared to those with LSM inside the tumor of <1.25 m/s.

CONCLUSIONS

LSM can serve as a potential non-invasive predictor for HCC clinical behavior and the recurrence-free interval following loco-regional treatments.

Liver stiffness measurement at complete virological response in hepatoma prediction for HBV-related cirrhosis patient with potent antiviral agent

Hepatocellular carcinoma (HCC) development is ameliorated with nucleos(t)ide agent (NA) therapy for hepatitis B virus (HBV)-related cirrhosis patients. This study investigates whether liver stiffness (LS) measurement at complete virological response (CVR) was useful in predicting HCC development. Between July 2006 and August 2016, HBV-related cirrhosis patients with potent NA (entecavir/tenofovir) with the first LS measurement during CVR and with serial LS were enrolled. Patients developing HCC 6 months after potent NA or before the first LS measurement were excluded. Three hundred and seventy-one patients were enrolled. The median follow-up was 5.6 and 3.8 years from potent NA treatment and the first LS measurement respectively. Twenty-seven patients developed HCC. The 1-, 3-, 5- and 7-year cumulated incidences of HCC occurrence were 0%, 2.8%, 5.8% and 9%, respectively. In addition to age > 57 years, LS > =21.5 kPa (HR: 3.86, 95%CI: 1.67-8.94) was an independent factor associated with HCC occurrence in multivariate analysis. However, the magnitude of change in LS was not associated with HCC development. For the first LS in HCC prediction, the performance was 0.636. There were two to thirteen LS measurements during CVR. The change in LS was classified into four patterns stratified by the first and serial LS. Compared with those with serial LS < 21.5 kPa, patients with LS > =21.5 kPa tend to have higher HCC occurrence (P = .062). In summary, LS at CVR was an independent factor associated with HCC development for HBV-related cirrhosis patients with potent NA. However, LS was not satisfactory in the prediction performance of HCC development.

Fibrosis evolution in chronic hepatitis B e antigen-negative patients across a 10-year interval

The degree of liver fibrosis in chronic hepatitis B (CHB) infection influences outcome and management. Existing data describing the long-term dynamic changes of liver fibrosis are limited. This study aimed to evaluate the evolution of liver fibrosis in CHB across a 10-year period. CHB patients with liver stiffness measurement (LSM) by transient elastography 10 years ago were recruited for follow-up LSM. Fibrosis stages were classified according to EASL-ALEH guidelines. Fibrosis progression/regression was arbitrarily defined as ≥1 fibrosis stage change from baseline. A total of 459 hepatitis B e antigen (HBeAg)-negative patients (224 untreated, 235 treated with nucleos(t)ide analogues [NAs]) were recruited. The mean age at baseline LSM was 41.7 ± 9.0 years (56.2% male). Over 10 years, the proportion of patients with advanced fibrosis/cirrhosis significantly reduced from 16.3% to 5.7% (P < 0.001). Fibrosis progression and regression were observed in 8.7% and 37.5%, respectively. No treatment with NAs (OR 2.259, 95% confidence interval [CI]: 1.032-4.945), metabolic syndrome (OR 4.379, 95% CI: 1.128-16.999) and hepatic steatosis (OR 7.799, 95% CI: 2.271-26.776) was associated with fibrosis progression. Liver stiffness decline demonstrated positive correlation with the time after HBsAg seroclearance (r = -0.50, P < 0.001). Median liver stiffness was higher both at baseline (14.0 vs 6 kPa, P < 0.001) and 10 years (9.1 vs 4.9 kPa, P < 0.001) in patients with cirrhosis-related complications/hepatocellular carcinoma compared with those without. In conclusion, CHB-related liver fibrosis changed dynamically across 10 years. Metabolic syndrome and hepatic steatosis were associated with fibrosis progression, while antiviral therapy was associated with fibrosis regression. Patients with HBsAg seroclearance demonstrated time-dependent decline in liver stiffness.

Transient elastography (FibroScan®) with controlled attenuation parameter in the assessment of liver steatosis and fibrosis in patients with nonalcoholic fatty liver disease - Where do we stand?

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide. Currently, the routinely used modalities are unable to adequately determine the levels of steatosis and fibrosis (laboratory tests and ultrasonography) or cannot be applied as a screening procedure (liver biopsy). Among the non-invasive tests, transient elastography (FibroScan^®, TE) with controlled attenuation parameter (CAP) has demonstrated good accuracy in quantifying the levels of liver steatosis and fibrosis in patients with NAFLD, the factors associated with the diagnosis and NAFLD progression. The method is fast, reliable and reproducible, with good intra- and interobserver levels of agreement, thus allowing for population-wide screening and disease follow-up. The initial inability of the procedure to accurately determine fibrosis and steatosis in obese patients has been addressed with the development of the obese-specific XL probe. TE with CAP is a viable alternative to ultrasonography, both as an initial assessment and during follow-up of patients with NAFLD. Its ability to exclude patients with advanced fibrosis may be used to identify low-risk NAFLD patients in whom liver biopsy is not needed, therefore reducing the risk of complications and the financial costs.

Noninvasive assessment of alcoholic liver disease using unidimensional transient elastography (Fibroscan®)

Unidimensional transient elastography (TE) is a noninvasive technique, which has been increasingly used in the assessment of diffuse liver diseases. This paper focuses on reviewing the existing data on the use of TE in the diagnosis of fibrosis and in monitoring disease progression in alcoholic liver disease, on the factors that may influence the result of fibrosis prediction, and last but not least, on its potential use in assessing the steatosis degree. Therefore, this field is far from being exhausted and deserves more attention. Further studies are required, on large groups of biopsied patients, in order to find answers to all the remaining questions in this field.

Liver stiffness measurement for risk assessment of hepatocellular carcinoma

AIM

Liver fibrosis is a risk factor for hepatocellular carcinoma (HCC), but at what fibrotic stage the risk for HCC is increased has been poorly investigated quantitatively. This study aimed to determine the appropriate cut-off value of liver stiffness for HCC concurrence by FibroScan, and its clinical significance in hepatitis B virus (HBV), hepatitis C virus (HCV) and non-B, non-C (NBNC) liver disease.

METHODS

Subjects comprised 1002 cases (246 with HCC and 756 without HCC) with chronic liver disease (HBV, 104; HCV, 722; and NBNC, 176).

RESULTS

Liver stiffness was significantly greater in all groups with HCC, and the determined cut-off value for HCC concurrence was more than 12.0 kPa in those with HCV, more than 8.5 kPa in those with HBV and more than 12.0 kPa in those with NBNC. Liver stiffness of more than 12.0 kPa was an independent risk factor for new HCC development in HCV. For HCV, risk factors for HCC concurrence were old age, male sex, low albumin, low platelets and liver stiffness, while for HBV they were old age, low platelets and liver stiffness, and for NBNC they were old age, elevated α-fetoprotein and liver stiffness.

CONCLUSION

Liver stiffness cut-off values and their association with HCC concurrence were different depending on the etiology. In HCV, liver stiffness of more than 12.0 kPa was an independent risk factor for new HCC development. Collectively, determining the fibrotic cut-off values for HCC concurrence would be important in evaluating HCC risks.

Hagen-Poiseuille’s law: The link between cirrhosis, liver stiffness, portal hypertension and hepatic decompensation

The onset of hepatic decompensation in cirrhosis heralds an accelerated downhill course with poor outcome. The sole predictor of this decompensation in cirrhosis is increased hepatic vein to portal vein gradient hepatic venous pressure gradient (HVPG). Surrogate markers of liver function or hepatic reserve appear to be less relevant. The hepatic sinusoids become less elastic and more rigid as liver fibrosis and cirrhosis progress. We propose that the Hagen-Poiseuille’s law, which applies to rigid, but not elastic vessels, determines the pressure-flow characteristics in the sinusoids. In the rigid cirrhotic liver, HVPG rises dramatically with any change in net surface area or radius, r⁴ of the vasculature that follows surgical resection. This review relates liver stiffness to the risk of decompensation in patients with cirrhosis. The liver has a unique dual blood supply comprising a low pressure portal vein and high pressure hepatic artery. We compare the complexity of autoregulation in the normal elastic liver with that in the rigid cirrhotic liver. Therapeutic modalities to reduce portal pressure may reduce the risk of hepatic decompensation and improve outcomes in cirrhosis.

Management of Hepatocellular Carcinoma in Cirrhotic Patients with Portal Hypertension: Relevance of Hagen-Poiseuille's Law

BACKGROUND

Hepatic decompensation in cirrhosis heralds an accelerated course with poor survival. An increase in hepatic venous pressure gradient (HVPG), rather than surrogate tests of liver function, appears to be the sole predictor of decompensation after surgical resection. We propose that hepatic sinusoidal walls become less elastic as cirrhosis progresses. Decompensation signals the development of increased vessel wall rigidity. The pressure-flow characteristics then become subject to Hagen-Poiseuille's law, which applies only to rigid, cylindrical vessels. Thereafter, HVPG rises exponentially (by a factor inversely proportional to the fourth power of the net radius of functional sinusoidal vessels, 1/r(4), at any given hepatic blood flow rate. This review attempts to correlate liver stiffness, risk of decompensation and outcomes from hepatocellular carcinoma (HCC) in patients with cirrhosis.

SUMMARY

We compare the complexity of autoregulation in the normal elastic liver, which has a unique dual blood supply, with that in the rigid cirrhotic liver. We also review, in the context of background liver cirrhosis, the management of HCC which is in essence, a solid mass of unorganized cells that exacerbates liver stiffness. We discuss the differential effects of various therapeutic modalities such as liver transplantation, loco-regional therapy and drugs on HCC outcomes, based on their effects on HVPG.

KEY MESSAGES

Increased hepatic artery supply, or the hepatic artery buffer response, may be the only available method for autoregulation or maintenance of hepatic blood flow in the cirrhotic liver. In HCC, loco-regional therapies, including partial resection of the cirrhotic liver, can exacerbate portal hypertension by increasing blood flow within the remnant organ. We conclude that studies of HVPG reduction as part of HCC management may be beneficial and are warranted.

Latest developments in the imaging of fibrotic liver disease

According to the World Health Organization, liver cirrhosis accounted for 1.8% of all deaths in Europe, causing about 170,000 deaths per year. Approximately 29 million persons in the EU suffer from chronic liver disease and this trend is on the rise. Liver disease is the EU's fifth most common cause of death accounting for at least one in six deaths. Early detection and monitoring of fibrosis has the potential to direct management of these chronic liver diseases and avert morbidity and mortality. Although the available techniques are in their infancy and the very early stages of fibrosis are difficult to detect, there have been significant advances in imaging over the last decade that has resulted in the use of these new imaging techniques being introduced into the patient pathway. This review explores the accuracies of these imaging techniques, their role in the management of patients, and the potential for the future.

Non-invasive prediction of development of hepatocellular carcinoma using transient elastography in patients with chronic liver disease

Prognosis of patients with chronic liver disease is determined by the extent and progression of liver fibrosis, which may ultimately lead to hepatocellular carcinoma (HCC). Liver biopsy (LB) is regarded as the gold standard to estimate the extent of liver fibrosis. However, because LB has several limitations, the foremost being its invasiveness, several non-invasive methods for assessing liver fibrosis have been proposed. Of these, transient elastography (TE) provides an accurate representation of the extent of liver fibrosis. Furthermore, recent studies have focused on the usefulness of TE for assessing the risk of HCC development and HCC recurrence after curative treatment, and developed novel models to calculate the risk of HCC development based on TE findings. These issues are discussed in this expert review.

Value of shear wave velocity measurements for the risk assessment of hepatocellular carcinoma development in patients with nonalcoholic fatty liver disease : HCC risk assessment by VTTQ

PURPOSE

To evaluate the value of measuring shear wave velocity evoked by acoustic radiation force impulse (VTTQ) for the risk assessment of hepatocellular carcinoma (HCC) development in patients with nonalcoholic fatty liver disease (NAFLD).

METHODS

VTTQ was measured three times in each of the four liver segments in 163 NAFLD patients, including 14 HCC cases; the results were statistically evaluated.

RESULTS

The VTTQ was 3.04 ± 0.17 m/s (median ± median absolute deviation) and 1.27 ± 0.25 m/s in patients with and without HCC, respectively, and was significantly higher in HCC cases (p < 0.001). When the patients were classified as F0-F4 based on VTTQ cutoff values, VTTQ was significantly higher in the left lobe than in the right lobe for F0 (p < 0.0001) and for F1 and F2 combined (p < 0.0001), but not significantly higher for F3 and F4 combined (p = 0.070). The robust coefficient of variation was significantly higher in the left than in the right (p = 0.018) and significantly increased as VTTQ increased (p = 0.0002). Multivariate analysis showed that total bilirubin concentration {p = 0.014, 38.9 (2.08-727) [odds ratio (95 % confidence interval)]} and VTTQ [p = 0.006, 113 (3.91-3245)] were the only independent explanatory factors for HCC presence among the seven variables identified by univariate analysis. The area under the receiver-operating characteristic curve in the differentiation of HCC from non-HCC was 0.943 for VTTQ and was comparable to that for other noninvasive markers such as Fib-4 (0.964) or higher than that in BARD (0.838).

CONCLUSIONS

These results suggest that fibrosis occurs heterogeneously throughout the liver and that VTTQ measurements are useful in HCC risk evaluation in a NAFLD cohort.

Diffusion Weighted MRI for Hepatic Fibrosis: Impact of b-Value

Background

Hepatic fibrosis is a typical complication of chronic liver diseases resulting in cirrhosis that remains a major public health problem worldwide. Liver biopsy is currently the gold standard for diagnosing and staging hepatic fibrosis. Percutaneous liver biopsy; however, is an invasive procedure with risks of complications. Therefore, there is need for alternative non-invasive techniques to assess liver fibrosis and chronic liver diseases. In recent years, MRI techniques, including diffusion weighted imaging (DWI), have been developed for in vivo quantification of liver fibrosis.

Objectives

The purpose of this study is to evaluate the utility of diffusion weighted MRI in the diagnosis and quantification of the degree of hepatic fibrosis and to investigate the influence of b-value.

Patients and Methods

Twenty-four patients (13 males, 11 females), with a mean age of 46 years (36-73 years) diagnosed as chronic hepatitis and histopathologically proven liver fibrosis and 22 other patients (8 males, 14 females) with no clinical or biochemical findings of liver disease, with a mean age of 51.2 years (32-75 years) were included in the study. All patients with chronic hepatitis underwent percutaneous liver biopsy by an experienced hepatologist without sonographic guidance. The Knodell histology activity index (HAI) for grading of necroinflammatory changes and Metavir scoring system for staging of the liver fibrosis were used to record the severity of the disease. All patients were examined with a 1.5 Tesla MRI system and the patients underwent diffusion weighted imaging (DWI) with a routine hepatic MRI protocol. Different b-values including 250, 500, 750, and 1000 sec/mm ² were used to calculate apparent diffusion coefficients.

Results

We detected decreased apparent diffusion coefficient values in patients with hepatic fibrosis compared to patients without chronic hepatitis and there was a trend toward decrease in hepatic apparent diffusion coefficient values with an increasing degree of fibrosis.

Conclusions

Our findings suggest that hepatic apparent diffusion coefficient measurement with a b-value of 750 sec/mm ² or greater is useful in accurate quantification of liver fibrosis and necroinflammation.

Non-invasive assessment of liver fibrosis in patients with chronic hepatitis B

In patients with chronic hepatitis B (CHB), liver fibrosis assessment is essential not only for determining prognosis but also for identifying patients who should receive treatment. Liver biopsy is limited by its invasiveness and sampling error. To explore effective non-invasive methods for liver fibrosis assessment, we reviewed international literature published over the past decade that focused on patients with CHB. Biomarker panels such as API, FIB-4, Forns Index, HepaScore, FibroMeter, FibroTest, Zeng Index and Hui Index detect advanced fibrosis and cirrhosis with fairly satisfactory accuracy with area under the receiver-operating characteristics curve higher than 0.85. However, most panels and the suggested cutoffs have not been independently validated. Transient elastography is accurate in detecting advanced fibrosis and cirrhosis, and the relative cutoffs have been defined. False-positive results may, however, occur in cases of active necroinflammation and cholestasis. Other promising imaging methods such as acoustic radiation force impulse and magnetic resonance elastography still require further validating studies. We conclude that transient elastography, FibroTest and API are the most widely validated. Transient elastography has been validated as the most useful non-invasive method for liver fibrosis assessment. To improve non-invasive performance of detecting liver fibrosis, a combined application of transient elastography and biomarkers may be the preferred course of action.

Liver stiffness measurement as an alternative to fibrotic stage in risk assessment of hepatocellular carcinoma incidence for chronic hepatitis C patients

BACKGROUND

Hepatic fibrosis stage is useful in assessing risk of hepatocellular carcinoma (HCC) occurrence.

AIM

To evaluate liver stiffness measurement (LSM), in addition to fibrosis stage, in risk assessment of long-term HCC occurrence for patients with chronic hepatitis C.

PATIENTS AND METHODS

Consecutive patients with chronic hepatitis C, without past history and presence of HCC, with concomitant liver biopsy and LSM were enrolled in this study. All patients attended regular surveillance for HCC development every 3-12 months. The medical records were reviewed. Follow-up LSM was performed at least 1 year later.

RESULTS

One hundred and ninety-eight patients (M/F: 112/86) with reliable LSM results were enrolled. Ten patients developed HCC in a median follow-up period of 47.8 months. For patients with initial LSM >24 kPa, 12-24 kPa, and <12 kPa, 5- year HCC incidence was 45.1%, 9.5% and 0.9% respectively. Multivariate analysis showed patients with LSM>24 kPa and patients with LSM 12-24 kPa had higher risks of HCC development (HR: 24.6, CI: 2.7-220.4 and HR:11.7, CI:1.3-105.2). Patients without sustained virological response after treatment also had higher risk of HCC occurrence (HR: 9.7, CI: 1.1-82.2). Among 106 patients with follow-up LSM, there was a higher risk of HCC development for patients with LSM>12 kPa in the initial and follow-up LSM.

CONCLUSION

As an alternative of fibrosis stage, initial LSM is useful as a non-invasive method in risk assessment of HCC occurrence for patients with chronic hepatitis C. Serial follow-up LSM>12 kPa carries higher risk of HCC development.

Keratin 8/18 regulation of cell stiffness-extracellular matrix interplay through modulation of Rho-mediated actin cytoskeleton dynamics

Cell mechanical activity generated from the interplay between the extracellular matrix (ECM) and the actin cytoskeleton is essential for the regulation of cell adhesion, spreading and migration during normal and cancer development. Keratins are the intermediate filament (IF) proteins of epithelial cells, expressed as pairs in a lineage/differentiation manner. Hepatic epithelial cell IFs are made solely of keratins 8/18 (K8/K18), hallmarks of all simple epithelia. Notably, our recent work on these epithelial cells has revealed a key regulatory function for K8/K18 IFs in adhesion/migration, through modulation of integrin interactions with ECM, actin adaptors and signaling molecules at focal adhesions. Here, using K8-knockdown rat H4 hepatoma cells and their K8/K18-containing counterparts seeded on fibronectin-coated substrata of different rigidities, we show that the K8/K18 IF-lacking cells lose their ability to spread and exhibit an altered actin fiber organization, upon seeding on a low-rigidity substratum. We also demonstrate a concomitant reduction in local cell stiffness at focal adhesions generated by fibronectin-coated microbeads attached to the dorsal cell surface. In addition, we find that this K8/K18 IF modulation of cell stiffness and actin fiber organization occurs through RhoA-ROCK signaling. Together, the results uncover a K8/K18 IF contribution to the cell stiffness-ECM rigidity interplay through a modulation of Rho-dependent actin organization and dynamics in simple epithelial cells.

Liver stiffness measured by transient elastography is a predictor of hepatocellular carcinoma development in viral hepatitis

AIM

  To investigate the value of liver stiffness in diagnosing hepatocellular carcinoma (HCC) among patients with viral hepatitis, and to prospectively investigate relationships between liver stiffness and HCC development.

METHODS

  Liver stiffness was measured by transient elastography for 157 patients with viral hepatitis, along with various other parameters potentially associated with HCC. HCC was initially present in 41 patients and absent in 116 patients, of whom 106 patients were followed prospectively for HCC development. Diagnostic performances of liver stiffness and other clinical parameters in predicting presence of HCC were evaluated using receiver operating characteristic (ROC) curves and area under the ROC curve (AUROC).

RESULTS

  Liver stiffness was significantly higher in patients with HCC (24.9 ± 19.5 kPa) than in patients without HCC (10.9 ± 8.4 kPa; P < 0.0001). Age (P < 0.0001), platelet cell count (P = 0.0001), prothrombin activity (P = 0.0009), alpha fetoprotein (P = 0.0091), and des-gamma-carboxy prothrombin (DCP) (P = 0.0099) also differed significantly between patients with and without HCC. The largest AUROC was for liver stiffness. Differences between liver stiffness and age, platelet cell count, prothrombin activity, and DCP were not significant, but the AUROC of liver stiffness was superior to that of alpha fetoprotein (P = 0.03850). Using a cut-off liver stiffness of 12.5 kPa, development of HCC was identified in 10 of the 106 patients followed. Multivariate analysis identified liver stiffness ≥12.5 kPa, age ≥60 years, and serum total bilirubin ≥1.0 mg/dL as significantly correlated with development of HCC.

CONCLUSIONS

  Liver stiffness as measured by transient elastography is a predictor of HCC development in viral hepatitis.

Liver stiffness measurement using transient elastography and hepatocellular carcinoma

Liver fibrosis has been gaining noticeable attention because it may lead to end-stage liver cirrhosis and ultimately to hepatocellular carcinoma. Thus, a precise estimation of the degree of liver fibrosis is crucial for predicting prognosis and deciding management of patients with chronic liver diseases. Many non-invasive approaches for the evaluation of liver fibrosis have been developed. Among these procedures, transient elastography has recently drawn great attention. Transient elastography has been reported to be well correlated with the degree of liver fibrosis by many investigators and various institutions. Since the degree of liver fibrosis is considered as a strong predictor of risk for hepatocellular carcinoma development, several trials have been performed to verify the usefulness of measurement of liver stiffness to predict the emergence of hepatocellular carcinoma. From these studies, transient elastography seems to be a promising procedure to predict the risk of hepatocellular carcinoma; however, further cohorts with long-term monitoring of liver stiffness are needed to confirm the usefulness of this method.