Elevated 2-oxoglutarate antagonizes DNA damage responses in cholangiocarcinoma chemotherapy through regulating aspartate beta-hydroxylase.

Cholangiocarcinoma (CCA) is resistant to systemic chemotherapies that kill malignant cells mainly through DNA damage responses (DDRs). Recent studies suggest that the involvement of 2-oxoglutarate (2-OG) dependent dioxygenases in DDRs may be associated with chemoresistance in malignancy, but how 2-OG impacts DDRs in CCA chemotherapy remains elusive. We examined serum 2-OG levels in CCA patients before receiving chemotherapy. CCA patients are classified as progressive disease (PD), partial response (PR), and stable disease (SD) after receiving chemotherapy. CCA patients classified as PD showed significantly higher serum 2-OG levels than those defined as SD and PR. Treating CCA cells with 2-OG reduced DDRs. Overexpression of full-length aspartate beta-hydroxylase (ASPH) could mimic the effects of 2-OG on DDRs, suggesting the important role of ASPH in chemoresistance. Indeed, the knockdown of ASPH improved chemotherapy in CCA cells. Targeting ASPH with a specific small molecule inhibitor also enhanced the effects of chemotherapy. Mechanistically, ASPH modulates DDRs by affecting ATM and ATR, two of the major regulators finely controlling DDRs. More importantly, targeting ASPH improved the therapeutic potential of chemotherapy in two preclinical CCA models. Our data suggested the impacts of elevated 2-OG and ASPH on chemoresistance through antagonizing DDRs. Targeting ASPH may enhance DDRs, improving chemotherapy in CCA patients.

Randomized phase I/II study of vascular endothelial growth factor receptor peptide vaccines for patients with hepatocellular carcinoma.

AIM: We evaluated the safety and efficacy of vascular endothelial growth factor receptor (VEGFR)-targeted peptide vaccines for the immunization of patients with unresectable hepatocellular carcinoma (HCC) who had responded to transarterial chemoembolization. METHODS: Twenty-two patients were randomized 1:1 to receive VEGFR-targeted peptides or placebo. The primary end-point was the safety assessment of the immunization. The secondary end-points were evaluation of immunological responses and clinical outcomes. RESULTS: No severe adverse events were induced by the study agents. Among the 12 patients in the vaccine group, a VEGFR1-specific cytotoxic T lymphocyte (CTL) response was induced in eight (66.7%) patients and a VEGFR2-specific CTL response was induced in 10 (83.3%). The median progression-free survival (PFS) and overall survival (OS) rates were 4.8 and 52.0 months, respectively, in the vaccine group, and 2.7 and 21.8 months, respectively, in the placebo group. No statistically significant differences were found between the two groups (PFS p = 0.925, OS p = 0.190). When divided into two groups according to immunoreactivity, the median PFS of patients with and without a strong immune response to VEGFR1 were 7.4 and 2.7 months, and that to VEGFR2 were 10.6 and 2.7 months, respectively; there were significant differences according to the immune response. CONCLUSIONS: Immunotherapy with peptide vaccines targeting VEGFR1 and VEGFR2 was well tolerated with no serious adverse events. It also effectively induced peptide-specific CTLs in patients with unresectable HCC.

Dried blood spot-based host genome analysis technique targeting pathological associations with hepatitis B: Development and clinical application in the Cambodian population.

AIM: Reports of patients with hepatitis B have highlighted associations between polymorphisms in the human leukocyte antigen (HLA)-DPB1, CXCL13, and CXCR5 genes and disease pathology. Owing to its potential to contribute to the development of new diagnostic and therapeutic methods, we aimed to establish a reliable host genome analysis technique that can be used in countries with inadequate infrastructure. METHOD: We compared multiple commercially available kits for dried blood spot (DBS)-based sample collection to develop a basic DBS-based host genome analysis technique. We then collected blood samples from Cambodian patients with hepatitis  B and performed single-nucleotide polymorphism genotyping and HLA allele typing by the DBS system. RESULT: We were able to perform single-nucleotide polymorphism genotyping and HLA allele typing with host DNA samples obtained using a combination of a HemaSpot™ filter paper-based device and a SMITEST® EX-R&D DNA extraction kit. The accuracy of genotyping using samples obtained by this method was not inferior to one using samples obtained by venipuncture. In the Cambodian population, significant associations of HLA-DPB1*04:01 with protection against chronic hepatitis B virus (HBV) infection, and HLA-DPB1*05:01 and HLA-DPB1*13:01 with susceptibility to chronic HBV infection were identified. CONCLUSION: Based on the DBS system, we clarified the associations of HLA-DPB1 alleles with chronic HBV infection in the Cambodian population for the first time. Because the DBS is a low-cost, durable, transportable, and easy-to-handle modality, genetic analysis based on the DBS system is a feasible strategy for obtaining a deeper understanding of HBV epidemiology, especially in middle- or low-income countries.

Therapeutic Modifications without Discontinuation of Atezolizumab Plus Bevacizumab Therapy Are Associated with Favorable Overall Survival and Time to Progression in Patients with Unresectable Hepatocellular Carcinoma.

We retrospectively evaluated the impact of therapeutic modifications of atezolizumab (Atezo) plus bevacizumab (Bev) therapy (Atezo/Bev), including the interruption or discontinuation of both Atezo and Bev, and the reduction or discontinuation of Bev, on the outcome of patients with unresectable hepatocellular carcinoma (uHCC) (median observation period: 9.40 months). One hundred uHCC from five hospitals were included. Therapeutic modifications without discontinuation of both Atezo and Bev (n = 46) were associated with favorable overall survival (median not reached; hazard ratio (HR): 0.23) and time to progression (median: 10.00 months; HR: 0.23) with no therapeutic modification defined as the reference. In contrast, the discontinuation of both Atezo and Bev without other therapeutic modifications (n = 20) was associated with unfavorable overall survival (median: 9.63 months; HR: 2.72) and time to progression (median: 2.53 months; HR: 2.78). Patients with modified albumin-bilirubin grade 2b liver function (n = 43) or immune-related adverse events (irAEs) (n = 31) discontinued both Atezo and Bev without other therapeutic modifications more frequently (30.2% and 35.5%, respectively) than those with modified albumin-bilirubin grade 1 (10.2%) and without irAEs (13.0%). Patients with objective response (n = 48) experienced irAEs more frequently (n = 21) than those without (n = 10) (p = 0.027). Avoiding the discontinuation of both Atezo and Bev without other therapeutic modifications may be the optimal management of uHCC.

Development of performance indicators for hepatitis countermeasures as a tool for the assessment and promotion of liver cancer prevention in Japan.

BACKGROUND: Hepatitis countermeasures are being promoted by governments in Japan. We aimed to develop performance indicators (PIs) to assess the process and outcome of such countermeasures implemented for the prevention of viral hepatitis-related liver cancer at the national and prefectural government levels. METHODS: We developed 19 PIs for hepatitis countermeasures implemented by local governments, covering the morbidity and mortality of liver cancer, hepatitis testing, subsidy programs for examinations and antiviral treatment, and education on hepatitis patient care to healthcare workers. We analyzed the PIs for each prefecture from Fiscal Year (FY) 2018-2020. RESULTS: The morbidity and mortality of liver cancer significantly decreased in the study period. The percentage of municipalities conducting hepatitis screening was already high at 95% in FY2017. The usage rate of government-subsidized screenings did not change. The subsidy usage rate for periodic viral hepatitis examination significantly increased. Meanwhile, the subsidy usage rate for antiviral treatment of hepatitis B increased, whereas that for hepatitis C decreased. The number of certified healthcare workers providing care for hepatitis patients increased significantly, and these workers were efficiently placed at regional core centers, institutions specialized in liver diseases, health care centers, and municipal governments. Liver cancer mortality was positively correlated with hepatitis screening, subsidies for periodic examinations, and the number of hepatitis medical care coordinators but was negatively correlated with subsidies for anti-HCV therapy, suggesting that rigorous countermeasures were implemented in prefectures with high liver cancer mortality. CONCLUSIONS: The developed PIs could be a useful tool for monitoring government efforts and achievements, thereby providing basic data for setting practical goals in liver cancer prevention.

Comparison of endoscopic submucosal resection with ligation and endoscopic submucosal dissection for small rectal neuroendocrine tumors: A multicenter retrospective study.

Objectives: Endoscopic submucosal resection with band ligation (ESMR-L) and endoscopic submucosal dissection (ESD) are both standard endoscopic resection methods for rectal neuroendocrine tumors (NETs) <10 mm in size. However, there is no definitive consensus on which is better. Here, we compared the efficacy of ESMR-L and ESD for small rectal NETs. Methods: This was a multicenter retrospective cohort study including 205 patients with rectal NETs who underwent ESMR-L or ESD. Treatment outcomes were compared by univariate analysis, multivariate analysis, and inverse probability treatment weighting (IPTW) using propensity scores. Subgroup analysis evaluated the impact of the endoscopist's experience on the technical outcome. Results: Eighty-nine patients were treated by ESMR-L and 116 by ESD. The R0 resection rate was not significantly different between the two (90% vs. 92%, p = 0.73). The procedure time of ESMR-L was significantly shorter than for ESD (17 min vs. 52 min, p < 0.01) and the hospitalization period was also significantly shorter (3 days vs. 5 days, p < 0.01). These results were confirmed by multivariate analysis and also after IPTW adjustment. The procedure time of ESD was significantly prolonged by a less-experienced endoscopist (49 min vs. 70 min, p = 0.02), but that of ESMR-L was not affected (17 min vs. 17 min, p = 0.27). Conclusions: For small rectal NETs, both ESMR-L and ESD showed similar high complete resection rates. However, considering the shorter procedure time and shorter hospitalization period, ESMR-L is the more efficient treatment method, especially for less-experienced endoscopists.

Optimal management of lenvatinib therapy for patients with unresectable hepatocellular carcinoma by balancing the therapeutic effect with the relative dose intensity.

AIMS: We aimed to assess the optimal management of first or later-line lenvatinib therapy (LEN) for patients with unresectable hepatocellular carcinoma (uHCC), by clarifying the difference of degree between relative dose intensity (RDI) to achieve objective response (OR) and disease control (DC) by aiming at stable disease (SD), taking dose modifications into consideration. METHODS: One hundred uHCC patients who received LEN in first- or later-line settings, between April 2018 and December 2020 in our hospital were analyzed retrospectively. The factors associated with overall survival (OS), time to progression (TTP), OR and DC were assessed. The optimal cut-off values of RDI 4 weeks after initiation of LEN (RDI during cycle 1) and total RDI (RDI during all cycles) to predict achievement of OR and DC by aiming at SD were determined by receiver operator curve analysis. RESULTS: Achievement of OR and SD were favorable factors for OS (HR, 0.080 and 0.20) and TTP (HR, 0.052 and 0.073), with progressive disease defined as the reference. RDI ≥ 0.8 during cycle 1 and RDI ≥ 0.4 during cycle 1 contributed to achievement of OR (odds ratio, 3.28) and DC (odds ratio, 4.85), respectively. Experience of dose interruption was associated with a favorable TTP (HR, 0.58). The therapeutic line of LEN did not contribute to OS, TTP or best response. CONCLUSIONS: To achieve OR and SD for a favorable outcome of first- or later-line LEN, high and moderate early-phase RDI are required, respectively. The degree of RDI during LEN and tolerance need compatible by dose modifications.

Clusterin and Related Scoring Index as Potential Early Predictors of Response to Sorafenib in Hepatocellular Carcinoma.

Advanced hepatocellular carcinoma (HCC) remains a highly lethal malignancy, although several systemic therapeutic options are available, including sorafenib (SFN), which has been one of the standard treatment agents for almost a decade. As early prediction of response to SFN remains challenging, biomarkers that enable early prediction using a clinically feasible method are needed. Here, we report that the serum secretory form of clusterin (sCLU) protein and its related predictive index are potential beneficial biomarkers for early prediction of SFN response. Using high-throughput screening and subsequent multivariate analysis in the derivation cohort, we found that changes in the concentrations of CLU, vascular cell adhesion molecule-1 (VCAM1), and α-fetoprotein were significantly associated with response to SFN. Furthermore, we confirmed that an increase in CLU serum level 1 month after treatment initiation was significantly associated with shorter progression-free survival. In addition, "NR-index," which comprises these proteins, was evaluated as a tool for accurately predicting the efficacy of SFN and confirmed in the validation cohort. We also established SFN-resistant HepG2 cells (HepG2-SR) and found that sCLU significantly increased in HepG2-SR cells compared with normal HepG2 cells, and confirmed that HepG2-SR cells treated with SFN were resistant to apoptosis. The mechanism underlying activation of sCLU expression in acquired SFN resistance involves aberrant signaling and expression of Akt, mammalian target of rapamycin (mTOR), and a nutrient-related transcription factor, sterol regulatory element binding protein 1c (SREBP-1c). Furthermore, the PI3K and mTOR inhibitor BEZ235 markedly decreased sCLU expression in HepG2-SR cells. Conclusion: These results suggest that measurement of sCLU serum levels and the sCLU-related NR-index are promising clinical tools for the early prediction of SFN response in HCC. Additionally, sCLU-overexpressing HCC might be susceptible to mTOR inhibition.

Seamless support from screening to anti-HCV treatment and HCC/ decompensated cirrhosis: Subsidy programs for HCV elimination.

Viral hepatitis poses a major public health problem in Japan. Chronic viral hepatitis is a progressive liver disease that eventually develops into liver cirrhosis and liver cancer. Since nucleic acid analog therapy for hepatitis B and interferon-free therapy for hepatitis C have made it possible to control the disease status or eliminate the viruses, it is very important that more people receive hepatitis virus tests to confirm the presence of infection at an early stage, and that patients with hepatitis detected by the tests receive appropriate medical care. Currently, the government of Japan is implementing comprehensive measures for hepatitis control based on five key strategies. Moreover, the goal listed in the Basic Guidelines on Hepatitis Measures is to reduce the frequency of progression of hepatitis to cirrhosis or liver cancer through a scheme consisting of testing people for hepatitis, getting those who test positive to visit a medical institution and receive treatment, and providing appropriate and high-quality hepatitis care through specialized medical institutions and regional core centers for the management of liver disease. To achieve the goal, various subsidy programs including an expense subsidy system for hepatitis treatment have been implemented in Japan. It is important for healthcare professionals to have sufficient knowledge of public support for efficient hepatitis C virus (HCV)-related liver disease detection and care.

Applicability of APRI and FIB-4 as a transition indicator of liver fibrosis in patients with chronic viral hepatitis.

BACKGROUND AND AIMS: The usefulness of APRI or FIB-4 is well established as a non-invasive liver fibrosis marker at a point of diagnosis in patients with chronic liver disease. However, their applicability for the monitoring of progression of liver fibrosis over time is yet to be determined. We aimed to clarify the feasibility of APRI and FIB-4 for the longitudinal evaluation of liver fibrosis in patients with chronic hepatitis B and C. METHODS: This is a multi-center retrospective and prospective cohort study, enrolling 1029 patients with HCV and 384 patients with HBV who were histologically diagnosed by liver biopsy. The observation period of retrospective and prospective study was 14 and 12 years, respectively. The APRI and FIB-4 were traced back in cases of histologically diagnosed cirrhosis, and those were prospectively analyzed after biopsy in cases diagnosed as F3 of METAVIR score, respectively. RESULTS: The averaged APRI and FIB-4 exhibited time-dependent increase in the retrospective study of hepatitis C patients (increase by 0.09/year in APRI and 0.29/year in FIB-4). In the prospective study of untreated hepatitis C patients, such increases were 0.14/year in APRI and 0.40/year in FIB-4, respectively. Neither the average of APRI nor FIB-4 showed a specific tendency with hepatitis B patients and treatment-experienced hepatitis C patients. CONCLUSION: The APRI and FIB-4 may serve as a transition indicator of liver fibrosis in anti-viral treatment-naïve patients with chronic hepatitis C.

Conversion hepatectomy for advanced hepatocellular carcinoma after right portal vein transection and lenvatinib therapy.

BACKGROUND: Lenvatinib is a novel tyrosine kinase inhibitor that exhibits an antitumor effect on hepatocellular carcinoma (HCC). An established strategy that involves surgery and usage of lenvatinib for advanced HCC remains elusive. CASE PRESENTATION: A 58-year-old male patient with advanced HCC and untreated hepatitis B was referred to our hospital. The tumor at the right lobe was 10 cm in diameter with right portal vein thrombus. Because of the possible lung metastasis and concern about the remaining hepatic function after extended right hepatectomy, lenvatinib was initiated before surgery. After the confirmation of a sharp decrease of tumor markers during the 3-week lenvatinib therapy, only a right portal vein transection was done leaving the enlargement of the left lobe for improved post-hepatectomy liver function while lenvatinib therapy was continued. The laparotomy revealed that the tumor was invading the right diaphragm. After 7 weeks of lenvatinib administration after right portal vein transection, an extended right hepatectomy with resection of the tumor-invaded diaphragm was successfully done. The lung nodules that were suspected as metastases had disappeared. The patient has been doing well without any sign of recurrence for 1 year. CONCLUSION: The strategy involving the induction of lenvatinib to conversion hepatectomy including the portal vein transection was effective for advanced HCC.

Loss of skeletal muscle mass affects the incidence of minimal hepatic encephalopathy: a case control study.

BACKGROUND: Sarcopenia is a syndrome characterized by progressive and systemic decreases in skeletal muscle mass and muscle strength. The influence or prognosis of various liver diseases in this condition have been widely investigated, but little is known about whether sarcopenia and/or muscle mass loss are related to minimal hepatic encephalopathy (MHE). METHODS: To clarify the relationship between MHE and sarcopenia and/or muscle mass loss in patients with liver cirrhosis. METHODS: Ninety-nine patients with liver cirrhosis were enrolled. MHE was diagnosed by a neuropsychiatric test. Skeletal mass index (SMI) and Psoas muscle index (PMI) were calculated by dividing skeletal muscle area and psoas muscle area at the third lumbar vertebra by the square of height in meters, respectively, to evaluate muscle volume. RESULTS: This study enrolled 99 patients (61 males, 38 females). MHE was detected in 48 cases (48.5%) and sarcopenia in 6 cases (6.1%). Patients were divided into two groups, with or without MHE. Comparing groups, no significant differences were seen in serum ammonia concentration or rate of sarcopenia. SMI was smaller in patients with MHE (46.4 cm2/m2) than in those without (51.2 cm2/m2, P = 0.027). Similarly, PMI was smaller in patients with MHE (4.24 cm2/m2) than in those without (5.53 cm2/m2, P = 0.003). Skeletal muscle volume, which is represented by SMI or PMI was a predictive factor related to MHE (SMI ≥ 50 cm2/m2; odds ratio 0.300, P = 0.002, PMI ≥ 4.3 cm2/m2; odds ratio 0.192, P = 0.001). CONCLUSIONS: Muscle mass loss was related to minimal hepatic encephalopathy, although sarcopenia was not. Measurement of muscle mass loss might be useful to predict MHE.

Nationwide survey on activities of regional core centers for the management of liver disease in Japan: Cumulative analyses by the Hepatitis Information Center 2009-2017.

AIM: Regional core centers for the management of liver disease, which are located in every prefecture in Japan, not only take the lead in hepatitis care in their respective regions, but also serve a wide range of other functions, such as education, promotion of hepatitis testing, treatment, and research. METHOD: Since fiscal year 2010, the Hepatitis Information Center has conducted surveys of regional core centers throughout Japan regarding information about their facilities, programs for patient support, training, and education of medical personnel. RESULTS: By compiling and analyzing the results of these surveys, we have elucidated the status of regional core centers and the issues they currently have. We found that regional core centers have come to play widely varied roles in hepatitis treatment and have expanded their programs. These surveys also suggest that uniform accessibility of hepatitis treatment has been implemented throughout Japan. CONCLUSION: To continue serving their diverse roles, regional core centers require further development of hepatitis care networks that include specialized institutions, primary care physicians, and local and central governments; as well as collaboration with other professions and groups.

Efficient and practical dissemination of information on viral hepatitis in Japan: an effort by the Hepatitis Information Center, National Center for Global Health and Medicine.

One of the important missions of the Hepatitis Information Center is to disseminate information regarding liver disease. The Hepatitis Information Center, National Center for Global Health and Medicine (NCGM) has been endeavoring to ensure that reliable and up-to-date information on liver disease is accessible to all people, regardless of age, disability, and background. Described here are several initiatives with regard to the dissemination of information about liver disease including: i) Education tool for youth, ii) Conversion of materials on liver diseases into audio format for the visually impaired, and iii) Hepatic Disease Medical Navigation System (Hepatic Navi). Hepatic Navi is a web-based search tool that informs users of the location and other information concerning medical centers where people can be tested for the hepatitis virus for free or at reduced cost. Hepatic Navi consolidates data from 47 prefectures into one database. The system depicts data via an interface that can be accessed anywhere with a PC, tablet, smart phone, or mobile phone. As a result, it has become possible for anyone from anywhere to access information on hepatitis virus testing. By using Hepatic Navi, it is anticipated that general people in need feel free to access to the testing and further treatment for virus hepatitis.

Oral branched-chain amino acid granules improve structure and function of human serum albumin in cirrhotic patients.

BACKGROUND AND AIMS: The aim of this study was to evaluate structural and functional alterations of human serum albumin (HSA), with a special focus on the oxidized and reduced forms, in patients with chronic liver disease. We also investigated whether oral branched-chain amino acid (BCAA) supplementation could induce structural changes and improve the functions of HSA. METHODS: The proportion of reduced and oxidized HSA was determined in 16 healthy controls and in 20 chronic hepatitis and 100 cirrhotic patients with stable conditions. To evaluate the functional properties of HSA, this study focused on the antioxidant and binding functions. The radical scavenging activity and binding ability of purified HSA were measured in 68 participants. After BCAA administration for 6 months, 29 patients were evaluated for HSA structural changes, with 19 out of the 29 patients also analyzed for HSA functional changes. RESULTS: There was a significant decrease in the amounts of reduced HSA in conjunction with liver disease progression. Receiver operating characteristic curve analysis demonstrated that the levels of reduced HSA had high accuracy in determining disease progression. Functional alterations were strongly correlated to the levels of reduced HSA. BCAA supplementation led to substantial increases in the amount of reduced HSA. The altered HSA was able to scavenge significantly more radicals and restore the binding ability. CONCLUSION: This study describes structural alterations and functional disturbances of HSA in patients with chronic liver disease, and indicates that the levels of reduced HSA might reflect disease progression and the functional properties of HSA. Moreover, oral BCAA supplementation increases the amount of reduced HSA, thereby leading to the restoration of HSA function in cirrhotic patients.

Evaluation of sorafenib treatment and hepatic arterial infusion chemotherapy for advanced hepatocellular carcinoma: a comparative study using the propensity score matching method.

While sorafenib (SFN) is the established worldwide standard therapeutic agent for advanced hepatocellular carcinoma (HCC), hepatic arterial infusion chemotherapy (HAIC) is also considered a favorable treatment for some advanced HCCs. This study aimed to evaluate each treatment and provide an optimal therapeutic choice for advanced HCCs. We analyzed 72 patients treated with SFN and 128 patients receiving HAIC. Both treatment groups were analyzed for prognostic and disease progression factors, and matched pair analysis was performed using the propensity score matching method. The preferable status of intrahepatic lesions, that is, no lesions or only a single (< 3 cm) intrahepetic lesion, was positively associated with good prognosis and negatively associated with disease progression in the SFN group. Maximum tumor size (> 5 cm) and low albumin (≤ 3.4 g/dL) were poor prognostic and disease progression factors in the HAIC group. Analysis of 53 patients selected from each of the SFN and HAIC groups based on the propensity score matching method showed no significant differences in survival or disease progression between the two matched subgroups. On the other hand, progression-free survival (PFS) in the HAIC-matched subgroup was significantly longer than in the SFN-matched subgroup, particularly in patients with portal vein invasion (PVI) and/or without extrahepatic spread (EHS). The treatment efficacy of HAIC is similar to that of SFN regarding survival and disease progression. Longer PFS might be expected for HAIC compared with SFN, particularly in patients with PVI and/or without EHS.

Cys34-cysteinylated human serum albumin is a sensitive plasma marker in oxidative stress-related chronic diseases.

The degree of oxidized cysteine (Cys) 34 in human serum albumin (HSA), as determined by high performance liquid chromatography (HPLC), is correlated with oxidative stress related pathological conditions. In order to further characterize the oxidation of Cys34-HSA at the molecular level and to develop a suitable analytical method for a rapid and sensitive clinical laboratory analysis, the use of electrospray ionization time-of-flight mass spectrometer (ESI-TOFMS) was evaluated. A marked increase in the cysteinylation of Cys34 occurs in chronic liver and kidney diseases and diabetes mellitus. A significant positive correlation was observed between the Cys-Cys34-HSA fraction of plasma samples obtained from 229 patients, as determined by ESI-TOFMS, and the degree of oxidized Cys34-HSA determined by HPLC. The Cys-Cys34-HSA fraction was significantly increased with the progression of liver cirrhosis, and was reduced by branched chain amino acids (BCAA) treatment. The changes in the Cys-Cys34-HSA fraction were significantly correlated with the alternations of the plasma levels of advanced oxidized protein products, an oxidative stress marker for proteins. The binding ability of endogenous substances (bilirubin and tryptophan) and drugs (warfarin and diazepam) to HSA purified from chronic liver disease patients were significantly suppressed but significantly improved by BCAA supplementation. Interestingly, the changes in this physiological function of HSA in chronic liver disease were correlated with the Cys-Cys34-HSA fraction. In conclusion, ESI-TOFMS is a suitable high throughput method for the rapid and sensitive quantification of Cys-Cys34-HSA in a large number of samples for evaluating oxidative stress related chronic disease progression or in response to a treatment.