Sang Wook Choi's research while affiliated with St. Paul's School and other places

Controlling adverse events (AEs) through dose reduction can enhance drug adherence and treatment response. Currently, there is no guide for sorafenib dosing. The aim of this study was to evaluate whether sorafenib dosing could affect treatment outcomes. A total of 782 hepatocellular carcinoma (HCC) patients treated with sorafenib were evaluated for sorafenib dosing and its modifications via medical records at baseline and regular follow‐up. Study outcomes included progression‐free survival (PFS), overall survival (OS), sorafenib duration, cumulative dose, AEs and drug discontinuation. The median patient survival was 7.7 months. Overall, 242 (30.9%) patients underwent dose reduction and 121 (17.5%) discontinued sorafenib due to AEs. In multivariate analysis, dose reduction was identified to be independently predictive of PFS and OS. The 800‐to‐400 mg/day group provided significantly better PFS than the 800 mg/day‐maintained group or the 800‐to‐600 mg/day group. Likewise, the 800‐to‐400 mg/day group resulted in a significantly better OS than other dosing. However, dose reduction to 200 mg/day led to significantly worse PFS and OS. Hand‐foot skin reaction and drug discontinuation due to AEs were higher in the 800‐to‐600 mg/day group than the 800‐to‐400 mg/day group. The 800‐to‐400 mg/day group had significantly longer treatment duration and higher cumulative dose than the 800 mg/day‐maintained group. Sorafenib dose reduction can improve HCC survival and increase patient tolerance and adherence coupled with longer duration and higher cumulative dose. Dose reduction from 800 to 400 mg/day than to 600 mg/day is recommended when clinically warranted. However, dose reduction to 200 mg/day is not recommendable.

Aims To evaluate the efficacy and safety of 144-week tenofovir disoproxil fumarate (TDF) therapy in treatment-naïve chronic hepatitis B (CHB) patients in Korean. Methods In total, 579 treatment-naïve CHB patients at 11 medical centers were enrolled retrospective and prospective from September 2015 to January 2016 by design (NCT02533544). We evaluated the complete virologic response (CVR) rate and the renal safety of TDF. Results The overall CVR rate was 69.4%, 87.0%, and 89.7% at weeks 48, 96, and 144, respectively. In the HBeAg-positive CHB patients, the CVR rate at weeks 48, 96, and 144 was 61.4%, 83.1%, and 89.6%, respectively. The rates of HBeAg loss and seroconversion at weeks 48, 96, and 144 were 16.6%, 23.5%, 34.1%, and 7.6%, 8.9%, 13.3%, respectively. In HBeAg-negative CHB patients, the CVR rate at weeks 48, 96, and 144 was 82.5%, 93.2%, and 90.0%, respectively. The rate of alanine aminotransferase normalization was 36.9%, 45.4%, and 46.8% at weeks 48, 96, and 144, respectively. Of the CHB patients, 0.9% showed an elevated creatinine (> 0.5 mg/dL from baseline). Age (≥ 60 years) was significantly associated with a decline in renal function at week 144 (P < 0.0001). Comorbidities (diabetes or hypertension) showed the tendency to reduce renal function (P = 0.0624). Hepatocellular carcinoma developed in 10 (1.7%) patients and was related to cirrhosis. Conclusions TDF therapy induced sustained viral suppression and had a favorable safety profile over a 3-year period. However, close monitoring of renal function should be mandatory in treating CHB patients receiving TDF, particularly older patients.

Background A real‐life study is essential outside clinical trials. The aim is to evaluate the clinical outcomes of direct acting agents (DAA) for patients with chronic hepatitis C (CHC) in real practice. Methods We analyzed 590 consecutively enrolled patients with CHC‐1b who received DAAs since 2015, when DAAs were introduced in Korea. The patients were checked for resistance‐associated variants (RAV) against nonstructural protein 5A inhibitors and then daclatasvir/asunaprevir or sofosbuvir based regimens were chosen. Results The frequency of patients with cirrhosis and prior hepatocellular carcinoma (HCC) was 29.2% and 4.7%, respectively. For the RAV test, 10% were positive and in 3.6% the result was “indeterminate.” Overall, 518 patients were treated with a 24‐week regimen of daclatasvir/asunaprevir, 72 patients (RAV positive 75%) were treated with 12 weeks regimen of ledipasvir/sofosbuvir or daclatasvir/sofosbuvir. The SVR12 was 94.0% in the daclatasvir/asunaprevir, 98.2% in the ledipasvir/sofosbuvir and 100% in the daclatasvir/sofosbuvir group. 93.3% of SVR12 in the RAV‐“indeterminate” patients was not difference 95.0% in the RAV‐negative patients. Up to one year, de novo HCC occurrence and recurrence developed in 2.6% and 17.8%, respectively. HCC was more frequent in cirrhotic patients than in noncirrhotic patients (P = 0.000). Alfa fetoprotein (AFP) level at the end of treatment was a predicting factor for de novo HCC. Conclusions Optimizing the choice of DAAs according to RAV test resulted in high SVR among CHC‐1b Korean patients. This real practice multicenter cohort study suggests the importance of AFP and HCC surveillance in cirrhotic patients even after successful HCV therapy. This article is protected by copyright. All rights reserved.

Patients with chronic hepatitis C who achieve a sustained viral response after pegylated interferon therapy have a reduced risk of hepatocellular carcinoma, but the risk after treatment with direct‐acting antivirals is unclear. We compared the rates of early development of hepatocellular carcinoma after direct‐acting antivirals and after pegylated interferon therapy. We retrospectively analyzed 785 patients with chronic hepatitis C who had no history of hepatocellular carcinoma (211 treated with pegylated interferon, 574 with direct‐acting antivirals) and were followed up for at least 24 weeks after antiviral treatment. De novo hepatocellular carcinoma developed in 6/574 patients receiving direct‐acting antivirals and in 1/211 patients receiving pegylated interferon. The cumulative incidence of early hepatocellular carcinoma development did not differ between the treatment groups either for the whole cohort (1.05% vs. 0.47%, P = 0.298) or for those patients with Child–Pugh Class A cirrhosis (3.73% vs. 2.94%, P = 0.827). Multivariate analysis indicated that alpha‐fetoprotein level >9.5 ng/ml at the time of end‐of‐treatment response was the only independent risk factor for early development of hepatocellular carcinoma in all patients (P < 0.0001, hazard ratio 176.174, 95% confidence interval 10.768–2882.473) and in patients treated with direct‐acting agents (P < 0.0001, hazard ratio 128.402, 95% confidence interval 8.417–1958.680). In conclusion, the rate of early development of hepatocellular carcinoma did not differ between patients treated with pegylated interferon and those treated with direct‐acting antivirals and was associated with the serum alpha‐fetoprotein level at the time of end‐of‐treatment response. This article is protected by copyright. All rights reserved.

Epstein-Barr virus (EBV) infection varies in its clinical manifestations and severity. EBV can be a causative agent of hepatitis and may have a role in the pathogenesis of chronic autoimmune diseases including inflammatory bowel disease. A 24-year-old woman was admitted to our hospital, presenting with fever and elevated liver enzymes. She was diagnosed with acute hepatitis and EBV infection according to serologic tests and liver biopsy. Within two months, she was re-admitted to our hospital, presenting with hematochezia and lower abdominal pain. She was diagnosed with ulcerative colitis. In situ hybridization for EBV was positive in initial liver biopsy and colon biopsy. Here we report an unusual case of acute EBV hepatitis followed at a short interval by ulcerative colitis.

Background and aims: Entecavir (ETV) is a potent nucleoside analogue with high genetic barrier to resistance. In this study, real-life clinical experiences in the long-term use of ETV and the durability of its off-treatment effectiveness were analyzed. Materials and methods: This study was based on a large real-life cohort of 2240 chronic hepatitis B patients treated with ETV between January 2006 and December 2012 using a centralized electronic data repository. Results: Among 2240 patients, 804 patients were treatment naive and underwent ETV monotherapy. Their mean treatment duration was 712±493 days, with a cumulative proportion of patients achieving HBV DNA less than 300 copies/ml in 85.8, 95.7, and 97.6% at years 1, 2, and 3, respectively. Predictors for earlier virologic response were female sex, lower HBV DNA, higher alanine transaminase, lower platelet count, and HBeAg negativity at baseline. In patients who achieved virologic response and HBeAg loss, the cumulative relapse rate was 91.3% in 2 years after the cessation of treatment. During the treatment, 34 patients developed hepatocellular carcinoma, among whom 30 patients had cirrhosis before treatment initiation. ETV treatment showed efficient virologic response as the treatment duration was extended, but off-treatment efficacy was not durable, and the antiviral treatment showed some limitation in preventing hepatocellular carcinoma among liver cirrhosis patients, implying that treatment cessation should be taken into consideration more carefully. Conclusion: This study from a real-life cohort may provide data on treating chronic hepatitis B patients more close to everyday clinical practice.

It was reported that dual specificity phosphatase 1 (DUSP1) is specifically upregulated in the liver of patients with chronic hetpatitis C virus (HCV) infection who do not respond to peginterferon (PegIFN) treatment. Here, we have investigated the role of DUSP1 in HCV replication in hepatoma cells stably expressing the full HCV replicon (FK). DUSP1 was silenced in cells harboring the FK replicon using a lentiviral vector encoding a DUSP1-specific short hairpin RNA (LV-shDUSP1). We demonstrated that knock-down of DUSP1 significantly inhibited HCV RNA and protein expression. Also, DUSP1 silencing enhanced the expression of phosphorylated signal transducer and activator of transcription 1 (phosho- STAT1) and facilitated the translocation of STAT1 into the nucleus. The mRNA expression levels of myxovirus resistance protein A (MxA), 2'-5'-oligoadenylate synthetase 1 (OAS1), ISG15 ubiquitin-like modifier (ISG15), chemokine C-X-C motif ligand 10 (CXCL10), and ubiquitin- specific protease 18 (USP18) were also accelerated by silencing of DUSP1. Furthermore, combined with the IFN treatment, DUSP1 silencing synergistically decreased the levels of HCV RNA. These results suggest that suppression of DUSP1 expression enhances phosphorylation and nuclear translocation of STAT1, resulting in increasing expression of interferon-stimulated genes (ISGs), which synergizes with IFN's antiviral effect against HCV. In conclusion, DUSP1 is involved in the antiviral host defense mechanism against a HCV infection and thus DUSP1 might be a target to treat chronic HCV infection.

To evaluate the applicability of AIMS65 scores in predicting outcomes of peptic ulcer bleeding. This was a retrospective study in a single center between January 2006 and December 2011. We enrolled 522 patients with upper gastrointestinal haemorrhage who visited the emergency room. High-risk patients were regarded as those who had re-bleeding within 30 d from the first endoscopy as well as those who died within 30 d of visiting the Emergency room. A total of 149 patients with peptic ulcer bleeding were analysed, and the AIMS65 score was used to retrospectively predict the high-risk patients. A total of 149 patients with peptic ulcer bleeding were analysed. The poor outcome group comprised 28 patients [male: 23 (82.1%) vs female: 5 (10.7%)] while the good outcome group included 121 patients [male: 93 (76.9%) vs female: 28 (23.1%)]. The mean age in each group was not significantly different. The mean serum albumin levels in the poor outcome group were slightly lower than those in the good outcome group (P = 0.072). For the prediction of poor outcome, the AIMS65 score had a sensitivity of 35.5% (95%CI: 27.0-44.8) and a specificity of 82.1% (95%CI: 63.1-93.9) at a score of 0. The AIMS65 score was insufficient for predicting outcomes in peptic ulcer bleeding (area under curve = 0.571; 95%CI: 0.49-0.65). The AIMS65 score may therefore not be suitable for predicting clinical outcomes in peptic ulcer bleeding. Low albumin levels may be a risk factor associated with high mortality in peptic ulcer bleeding.

The aims of this study were (1) to identify the useful clinical parameters of noninvasive approach for distinguishing nonalcoholic steatohepatitis (NASH) from nonalcoholic fatty liver disease (NAFLD), and (2) to determine whether the levels of the identified parameters are correlated with the severity of liver injury in patients with NASH. One hundred and eight consecutive patients with biopsy-proven NAFLD (age, 39.8±13.5 years, mean±SD; males, 67.6%) were prospectively enrolled from 10 participating centers across Korea. According to the original criteria for NAFLD subtypes, 67 patients (62.0%) had NASH (defined as steatosis with hepatocellular ballooning and/or Mallory-Denk bodies or fibrosis ≥2). Among those with NAFLD subtype 3 or 4, none had an NAFLD histologic activity score (NAS) below 3 points, 40.3% had a score of 3 or 4 points, and 59.7% had a score >4 points. Fragmented cytokeratin-18 (CK-18) levels were positively correlated with NAS (r=0.401), as well as NAS components such as lobular inflammation (r=0.387) and ballooning (r=0.231). Fragmented CK-18 was also correlated with aspartate aminotransferase (r=0.609), alanine aminotransferase (r=0.588), serum ferritin (r=0.432), and the fibrosis stage (r=0.314). A fragmented CK-18 cutoff level of 235.5 U/L yielded sensitivity, specificity, and positive and negative predictive values of 69.0%, 64.9%, 75.5% (95% CI 62.4-85.1), and 57.1% (95% CI 42.2-70.9), respectively, for the diagnosis of NASH. Serum fragmented CK-18 levels can be used to distinguish between NASH and NAFL. Further evaluation is required to determine whether the combined measurement of serum CK-18 and ferritin levels improves the diagnostic performance of this distinction.

Ribosomal proteins (RP) play key roles in the regulation of apoptosis, multidrug resistance and carcinogenesis. The aim of this study was to investigate the expression of ribosomal protein L36 (RPL36) in hepatocellular carcinoma (HCC) and to correlate it with clinicopathological parameters and clinical outcome. Liver specimens were obtained from 60 HCC patients who had undergone a partial hepatectomy. Expression of RPL36 in tumor tissue and surrounding non-tumorous tissues was evaluated on a tissue microarray by immunohistochemistry. RPL36 was expressed in 45 of 60 (75%) HCC by immunohistochemistry, but was not detected in corresponding non-tumors. RPL36 expression correlated significantly with serum levels of albumin (P= 0.044) and prothrombin time (P= 0.026), which reflect liver synthetic function. Moreover, expression of RPL36 was found to be higher in patients with early tumor stages (I/II) (P= 0.038) or without portal vein thrombosis (P= 0.005). In univariate analysis, patients with RPL36 expression revealed better overall survival (P= 0.037). By multivariate survival analysis, RPL36 expression was found to be an independent prognostic factor for overall survival (P= 0.026). Our data suggest that RPL36 may be involved in the early stage of hepatocarcinogenesis, and it can be used as an independent and potential prognostic marker for resected HCC.