Modeling Hepatocellular Carcinoma Cells Dynamics by Serological and Imaging Biomarkers to Explain the Different Responses to Sorafenib and Regorafenib.

In advanced HCC, tyrosine-kinase inhibitors obtain partial responses (PR) in some patients and complete responses (CR) in a few. Better understanding of the mechanism of response could be achieved by the radiomic approach combining digital imaging and serological biomarkers (α-fetoprotein, AFP and protein induced by vitamin K absence-II, PIVKA-II) kinetics. A physic-mathematical model was developed to investigate cancer cells and vasculature dynamics in three prototype patients receiving sorafenib and/or regorafenib and applied in seven others for validation. Overall four patients showed CR, two PR, two stable-disease (SD) and two progressive-disease (PD). The rate constant of cancer cells production was higher in PD than in PR-SD and CR (median: 0.398 vs. 0.325 vs. 0.316 C × day-1). Therapy induced reduction of neo-angiogenesis was greater in CR than in PR-SD and PD (median: 83.2% vs. 29.4% and 2.0%), as the reduction of cell-proliferation (55.2% vs. 7.6% and 0.7%). An additional dose-dependent acceleration of tumor vasculature decay was also observed in CR. AFP and cancer cells followed the same kinetics, whereas PIVKA-II time/dose dependent fluctuations were influenced also by tissue ischemia. In conclusion, pending confirmation in a larger HCC cohort, modeling serological and imaging biomarkers could be a new tool for systemic therapy personalization.

Modeling the time-related fluctuations of AFP and PIVKA-II serum levels in patients with cirrhosis undergoing surveillance for hepatocellular carcinoma.

BACKGROUND: The time-related variability of HCC biomarkers has not been investigated so far. OBJECTIVE: To assess the changes of alpha-fetoprotein (AFP) and protein induced by vitamin-K absence/antagonist-II (PIVKA-II) in patients with HCC (HCC+) as compared to patients without HCC (HCC-). METHODS: AFP and PIVKA-II were measured by a single laboratory using an automated chemiluminescent-enzyme-immunoassay (Fujirebio Inc., Tokyo, Japan) in 1163 sera of 418 cirrhotics (31.1% HBV, 58.6% HCV, 10.3% non-viral etiology) undergoing ultrasound HCC surveillance. The mean (range) number of effective time-points available for analysis was 2.8 (2.0 to 3.0); 124 patients with HCC were matched with 294 who remained HCC free for at least 12 months after the last specimen. AFP and PIVKA-II changes were estimated over time by means of a random-effect generalized least squares (RE-GLS) regression model under the missingness at random assumption. RESULTS: Patients with and without HCC had comparable chronic liver disease etiology and staging. AFP/PIVKA-II median (25th; 75th percentile) values at the latest time-point were 4.2 (2.6; 8.6) ng/mL/32 (25; 42) mAU/mL in HCC- and 8.4 (4.4; 32.1) ng/mL/66 (32; 192) mAU/mL in HCC+ (p< 0.001). Log10AFP and log10PIVKA-II time-changes differed in HCC+ and HCC- patients. In HCC+ patients, both log10AFP and log10PIVKA-II showed an increasing trend over time. In HCC- patients, log10PIVKA-II variations were minimal as compared to log10AFP variations. The percent increase of log10AFP at 6 months vs. baseline was 11% (95%CI 5 to 17%) and 5% (95%CI 1 to 8%) for log10PIVKA-II in HCC+vs. HCC- patients. CONCLUSIONS: The present retrospective study of the biological variability of AFP and PIVKA-II suggests that their time-related changes may serve as potential predictors of HCC. This topic needs to be addressed by longitudinal studies.

Combined GS-4774 and Tenofovir Therapy Can Improve HBV-Specific T-Cell Responses in Patients With Chronic Hepatitis.

BACKGROUND & AIMS: One strategy to treat chronic hepatitis B virus (HBV) infection could be to increase the functions of virus-specific T cells. We performed a multicenter phase 2 study to evaluate the safety and efficacy of GS-4774, a yeast-based therapeutic vaccine engineered to express HBV antigens, given with tenofovir disoproxil fumarate (TDF) to untreated patients with chronic HBV infection. METHODS: We performed an open-label study at 34 sites in Canada, Italy, New Zealand, Romania, South Korea, and United States from July 2014 to August 2016. Adults who were positive for HB surface antigen (HBsAg) > 6 months and levels of HBV DNA ≥2000 IU/mL who had not received antiviral treatment for HBV within 3 months of screening were randomly assigned (1:2:2:2) to groups given oral TDF 300 mg daily alone (n = 27; controls) or with 2, 10, or 40 yeast units GS-4774 (n = 168), administered subcutaneously every 4 weeks until week 20 for a total of 6 doses. Blood samples were collected and analyzed and patients received regular physical examinations. Efficacy was measured by decrease in HBsAg from baseline to week 24. Specific responses to HBV (production of interferon gamma [IFNG], tumor necrosis factor [TNF], interleukin 2 [IL2], and degranulation) were measured in T cells derived from 12 HBeAg-negative patients with genotype D infections, after overnight or 10 days of stimulation of peripheral blood mononuclear cells with peptides from the entire HBV proteome. T-regulatory cells were analyzed for frequency and phenotype. Data from studies of immune cells were compared with data on reductions in HBsAg, HBV DNA, and alanine aminotransferase in blood samples from patients. RESULTS: GS-4774 was safe and well tolerated but did not produce significant decreases in levels of HBsAg. Production of IFNG, TNF, and IL2 increased significantly at weeks 24 and 48, compared with baseline, in HBV-specific CD8+ T cells from patients given GS-4774 but not from controls. GS-4774 had greater effects on CD8+ than CD4+ T cells, which were not affected at all or very weakly by TDF with or without GS-4774. GS-4774 did not affect responses of T cells to other viruses tested. HBV core peptides induced the greatest production of IFNG by T cells following overnight stimulation, whereas HBV envelope antigens did not induce a response. Following 10 days of stimulation, production of IFNG and TNF increased with time of exposure to GS-4774; the greatest levels of responses were to HBV envelope antigens followed by core and polymerase peptides. We observed a correlation in patients given GS-4774 between increased T-cell functions and reductions in numbers of T-regulatory cells. CONCLUSIONS: In a phase 2 study of patients with chronic HBV infection given TDF with or without GS-4774, we found that vaccination can increase production of IFNG, TNF, and IL2 by CD8+ T cells exposed to antigenic peptides, with little effect on CD4+ T cells. Although GS-4774 did not reduce levels of HBsAg in patients, its strong immune stimulatory effect on CD8+ T cells might be used in combination with other antiviral agents to boost the antivirus immune response. Clinicaltrials.gov no: NCT02174276.

Impact of etiology of chronic liver disease on hepatocellular carcinoma biomarkers.

BACKGROUND: The role of serum biomarkers in the surveillance of hepatocellular carcinoma (HCC) is controversial. OBJECTIVE: We assessed the diagnostic performances of alpha-fetoprotein (AFP) and protein-induced by vitamin-K-absence/antagonist-II (PIVKA-II) in 388 cirrhotic patients with chronic liver disease (CLD). METHODS: Biomarkers were quantified by automated chemiluminescent-enzyme-immunoassays (Fujirebio, Tokyo, Japan) at HCC diagnosis in 258 patients (204 males; median age 66.9 years) and in 130 cirrhotics without HCC (104 males; median-age 60.6 years). CLD etiology in HCC/non-HCC was CHB in 48/35, CHC in 126/56 and Non-Viral in 84/39. RESULTS: Overall AUROC values for AFP and PIVKA-II were 0.698 (95%CI = 0.642-0.753, P< 0.001) and 0.780 (95%CI = 0.730-0.831, P< 0.001). AFP/PIVKA-II AUROC (95%CI) were: 0.822 (0.728-0.915)/0.833 (0.739-0.926) in CHB, 0.648 (0.560-0.736)/0.732 (0.650-0.814) in CHC; 0.640 (0.540-0.740)/0.806 (0.722-0.889) in Non-Viral-CLD. AFP/PIVKA-II diagnostic accuracy was 40.5-59.8%/62.7-73.5% and combining both markers 78.2% for CHB, 77% for Non-Viral-CLD and 75% for CHC. AFP correlated with ALT in HCC patients with CHC (ρ= 0.463/P< 0.001) and Non-Viral CLD (ρ= 0.359/P= 0.047), but not in CHB (treated with antivirals). PIVKA-II correlated with tumour size independently of CLD-etiology (P< 0.001) and AFP in CHB patients only (P= 0.007). CONCLUSION: The diagnostic performance of AFP and PIVKA-II is significantly influenced by the etiology and activity of CLD; their combination provides a better diagnostic accuracy.

Genome-Wide Comparison of Next-Generation Sequencing and qPCR Platforms for microRNA Profiling in Serum.

This study compares next-generation sequencing (NGS) technologies that have been optimized specifically for biofluid samples, with more established qPCR-based methods for profiling microRNAs in biofluids. The same patient serum samples were analyzed by NGS and qPCR, and differences in the serum microRNA profile between HBV and HCV infected patients were investigated. While there was overall good agreement between NGS and qPCR, there were some differences between the platforms, highlighting the importance of validation.

Immunotherapy of HCC metastases with autologous T cell receptor redirected T cells, targeting HBsAg in a liver transplant patient.

HBV-DNA integration frequently occurs in HBV-related hepatocellular carcinoma (HCC), but whether HBV antigens are expressed in HCC cells and can be targeted by immune therapeutic strategies remains controversial. Here, we first characterized HBV antigen expression in HCC metastases, occurring in a patient who had undergone liver transplantation for HBV-related HCC. We then deployed for the first time in HCC autologous T cells, genetically modified to express an HBsAg specific T cell receptor, as therapy against chemoresistant extrahepatic metastases. We confirmed that HBV antigens were expressed in HCC metastases (but not in the donor liver) and demonstrated that tumour cells were recognized in vivo by lymphocytes, engineered to express an HBV-specific T cell receptor (TCR). Gene-modified T cells survived, expanded and mediated a reduction in HBsAg levels without exacerbation of liver inflammation or other toxicity. Whilst clinical efficacy was not established in this subject with end-stage metastatic disease, we confirm the feasibility of providing autologous TCR-redirected therapy against HCC and advocate this strategy as a novel therapeutic opportunity in hepatitis B-associated malignancies.

Optimization of in vitro HBV replication and HBsAg production in HuH7 cell line.

The Gunther's vector-free method (GM), using PCR-amplified full length HBV-DNA (fl-HBV-DNA), is currently the best in vitro HBV replication system despite the low intracellular HBV-DNA production. The replication efficiency and HBsAg secretion of 12 isolates from HBsAg/HBeAg positive sera by GM, Monomer-Linear-Sticky-Ends-DNA (MLSE) and Monomer-Circular-Closed (MCC) were compared in HuH7 cells. Eight of twelve genomes (67%) were replication competent by GM; however direct sequencing (DS) showed that more than 80% of input DNA was undigested in spite of SapI treatment. Replication Intermediates (RI) were detected earlier (24 vs. 48h) and in higher amounts (2.51±0.32 and 6.43±0.43 fold) by MCC than GM or MLSE. By MCC 10 of 12 genomes (83%) were replication competent and 7 produced high RI levels. RI and HBsAg kinetics correlated positively in MCC (R=0.696, p=0.017 overall; R=0.928, p=0.008), but not in GM (R=-0.437, p=0.179 overall; R=-0.395, p=0.439) in genotype D isolates. In conclusion, HBV-DNA circularization prior transfection improves in vitro viral replication and replication competent HBsAg production, mimicking better the in vivo conditions.

In vitro liver model using microfabricated scaffolds in a modular bioreactor.

Hepatocyte function on 3-D microfabricated polymer scaffolds realised with the pressure-activated microsyringe was tested under static and dynamic conditions. The dynamic cell culture was obtained using the multicompartment modular bioreactor system. Hepatocyte cell density, glucose consumption, and albumin secretion rate were measured daily over a week. Cells seeded on scaffolds showed an increase in cell density compared with monolayer controls. Moreover, in dynamic culture, cell metabolic function increased three times in comparison with static monolayer cultures. These results suggest that cell density and cell-cell interactions are mediated by the architecture of the substrate, while the endogenous biochemical functions are regulated by a sustainable supply of nutrients and interstitial-like flow. Thus, a combination of 3-D scaffolds and dynamic flow conditions are both important for the development of a hepatic tissue model for applications in drug testing and regenerative medicine.

N-Glycans carried by Tamm-Horsfall glycoprotein have a crucial role in the defense against urinary tract diseases.

Tamm-Horsfall glycoprotein (THGP), produced exclusively by renal cells from the thick ascending limb of Henle's loop, is attached by a glycosyl-phosphatidylinositol (GPI)-anchor to the luminal face of the cells. Urinary excretion of THGP (50-100 mg/day) occurs upon proteolytic cleavage of the large ectodomain of the GPI-anchored form. N-Glycans, consisting of a large repertoire of sialylated polyantennary chains and high-mannose structures, account for approximately 30% of the weight of human urinary THGP. We describe: (i) the involvement of urinary THGP high-mannose glycans in defense against infections of the urinary tract, caused by type-1 fimbriated Escherichia coli, which recognize high-mannose structures, (ii) the role of GalNAcbeta1-4(NeuAcalpha2-3)Galbeta1-4GlcNAcbeta1-3Gal (Sd(a) determinant) carried by human THGP in protecting the distal nephron from colonization of type-S fimbriated E. coli which recognise NeuAcalpha2-3Gal, (iii) the inhibitory effect of sialylated THGP on crystal aggregation of calcium oxalate and calcium phosphate, thus preventing nephrolithiasis. Finally, we outline the importance of N-glycans in promoting the polymerization of THGP, a process resulting in the formation of homopolymers with an M(r) of several million in urine. Since THGP defense against diseases of the urinary tract mainly consists in binding damaging agents, its ability to behave as a multivalent ligand significantly enhances this protective role.

Tamm-Horsfall glycoprotein: biology and clinical relevance.

Tamm-Horsfall glycoprotein (THP) is the most abundant urinary protein in mammals. Urinary excretion occurs by proteolytic cleavage of the large ectodomain of the glycosyl phosphatidylinositol-anchored counterpart exposed at the luminal cell surface of the thick ascending limb of Henle's loop. We describe the physical-chemical structure of human THP and its biosynthesis and interaction with other proteins and leukocytes. The clinical relevance of THP reported here includes: (1) involvement in the pathogenesis of cast nephropathy, urolithiasis, and tubulointerstitial nephritis; (2) abnormalities in urinary excretion in renal diseases; and (3) the recent finding that familial juvenile hyperuricemic nephropathy and autosomal dominant medullary cystic kidney disease 2 arise from mutations of the THP gene. We critically examine the literature on the physiological role and mechanism(s) that promote urinary excretion of THP. Some lines of research deal with the in vitro immunoregulatory activity of THP, termed uromodulin when isolated from urine of pregnant women. However, an immunoregulatory function in vivo has not yet been established. In the most recent literature, there is renewed interest in the capacity of urinary THP to compete efficiently with urothelial cell receptors, such as uroplakins, in adhering to type 1 fimbriated Escherichia coli. This property supports the notion that abundant THP excretion in urine is promoted in the host by selective pressure to obtain an efficient defense against urinary tract infections caused by uropathogenic bacteria.