Long-term antitumor effect of lenvatinib on unresectable hepatocellular carcinoma with portal vein invasion

Lenvatinib is a novel multikinase inhibitor that has recently shown antitumor activity against hepatocellular carcinoma (HCC) in a phase III trial. We report the case of a woman in whom lenvatinib showed long-term antitumor activity, and in whom computed tomography (CT) scans revealed a series of suggestive radiological changes on the intratumor vascularity. A 68-year-old woman with hepatitis C virus-related liver disease presented with multiple HCCs. Following previous therapy, including six sessions of transcatheter arterial chemoembolization, we introduced lenvatinib monotherapy. Lenvatinib could rapidly cause hypovascularity in the main hypervascular target lesion, and portal vein tumor thrombosis also became undetectable 11 months after the initiation of lenvatinib. These radiological changes suggested that lenvatinib could exert not only anti-angiogenic activity but also direct antitumoral effect. Of note, CT scans during lenvatinib treatment revealed the target lesion as a low-density area in the early arterial phase, whereas scans during drug interruption due to proteinuria showed that the lesion was enhanced in the arterial phase. Finally, near-complete response could be achieved as the best response. We successfully managed various adverse events including proteinuria and hypertension, and the patient was able to continue this lenvatinib therapy for more than 4 years with well-controlled general condition. We report the first case of a patient with HCC in whom lenvatinib monotherapy demonstrated long-term antitumor activity. Suggestive radiological changes reflecting intratumor vascularity as presented here should be considered in patients receiving lenvatinib for HCC.

Underwater endoscopic mucosal resection: a new endoscopic method for resection of rectal neuroendocrine tumor grade 1 (carcinoid) ≤ 10 mm in diameter

Background and study aims  Rectal neuroendocrine tumors grade 1 (NET G1; carcinoid) ≤ 10 mm in diameter often extend into the submucosa, making their complete histological resection difficult using endoscopic techniques. Endoscopic submucosal resection with a ligation device (ESMR-L) and endoscopic submucosal dissection (ESD) are commonly used to overcome these difficulties. We also previously reported that underwater endoscopic mucosal resection (UEMR) could facilitate resection of rectal NET G1. This study aimed to evaluate the safety and efficacy of UEMR for removing rectal NET G1 ≤ 10 mm in diameter. 6 consecutive patients with rectal NET G1 ≤ 10 mm in diameter underwent UEMR at our hospital. The rate of en bloc resection was 100 %, and the rate of R0 resection was 83 %. The median procedure time was 8 min (range 5 - 12 min). No perforations or delayed bleeding occurred in this study. In conclusion, UEMR allows the safe and reliable resection of rectal NET G1 ≤ 10 mm in diameter with comparable results to ESMR-L or ESD, including high en bloc and R0 resection rates with no increase in significant adverse events. A multicenter trial is required to confirm the validity of the present results.

Cold snare polypectomy reduced delayed postpolypectomy bleeding compared with conventional hot polypectomy: a propensity score-matching analysis

BACKGROUND AND STUDY AIMS

 Cold snare polypectomy (CSP) for small colorectal polyps has lower incidence of adverse events, especially delayed postpolypectomy bleeding (DPPB). However, few data are available on comparisons of the incidence of DPPB of CSP and hot polypectomy (HP). The aim of this study was to evaluate the incidence of DPPB after CSP and compare it with that of HP. A propensity score model was used as a secondary analysis.

PATIENTS AND METHODS

 This was a retrospective cohort study conducted in a single municipal hospital. We identified 539 patients with colorectal polyps from 2 mm to 11 mm in size who underwent CSP (804 polyps in 330 patients) or HP (530 polyps in 209 patients) between July 2013 and June 2015.

RESULTS

 There were no cases of DPPB in the CSP group. Conversely, DPPB occurred in 4 patients (1.9 %) after HP, resulting in a significant difference between the CSP and HP groups (0.008 % vs 0 %, P  = 0.02). Propensity score-matching analysis created 402 matched pairs, yielding a significantly higher DPPB rate in the HP group than CSP group (0.02 % vs 0 %, P  = 0.04). However, significantly more patients in the CSP group had unclear horizontal margins that precluded assessment (83 vs 38 cases, P  < 0.001). The retrieval failure rate was significantly higher in the CSP group than in the HP group (3 % vs 0.7 %, P  = 0.01).

CONCLUSIONS

DPPB was less frequent with CSP than HP, as selected by the propensity score-matching model. Our findings indicate that CSP is recommended polypectomy in daily clinical setting. However, special care should be taken during polyp retrieval and horizontal margin assessment, and these issues could be taken into account in follow-up after CSP.

Prognostic significance of sarcopenia in patients with hepatocellular carcinoma undergoing sorafenib therapy

The present study aimed to examine the impact of sarcopenia, defined as low muscle mass on computed tomography (CT), prior to sorafenib therapy on the clinical outcomes of patients with hepatocellular carcinoma (HCC) receiving sorafenib therapy. In total, 232 patients with unresectable HCC (median age, 72 years) were analyzed, and the extent of sarcopenia was assessed using CT. Cross-sectional areas (cm²) of the skeletal muscles at the third lumbar vertebra level were determined by manual outlining on the CT images. The cross-sectional areas were normalized for height [skeletal muscle index (SMI), cm²/m²]. Based on the findings of previous studies, male patients with SMI ≤36.2 cm²/m² and female patients with SMI ≤29.6 cm²/m² were defined as having sarcopenia. The baseline characteristics, overall survival (OS) rates, progression-free survival (PFS) rates and best treatment response of the sarcopenia group were retrospectively compared with those of the non-sarcopenia group, and the factors associated with OS and PFS were examined. Sarcopenia was observed in 151 patients (65.1%). There were 165 patients with Child-Pugh A and 67 with Child-Pugh B cirrhosis. In the sarcopenia group, the median treatment duration was 66 days, whereas in the non-sarcopenia group it was 103 days (P=0.001). The median OS time was 174 days in the sarcopenia group and 454 days in the non-sarcopenia group (P<0.0001). The median PFS was 77 days in the sarcopenia group and 106 days in the non-sarcopenia group (P=0.0131). Multivariate analysis identified sarcopenia to be an independent predictor of OS (hazard ratio, 0.365; P<0.0001). The objective response rate and disease control rate in the sarcopenia group were significantly lower, compared with those in the non-sarcopenia group (P=0.0146 and P=0.0151, respectively). In conclusion, sarcopenia may be an indicator of poor clinical course in patients with HCC receiving sorafenib.

Predictive factors in patients with hepatocellular carcinoma receiving sorafenib therapy using time-dependent receiver operating characteristic analysis

Aims: To investigate variables before sorafenib therapy on the clinical outcomes in hepatocellular carcinoma (HCC) patients receiving sorafenib and to further assess and compare the predictive performance of continuous parameters using time-dependent receiver operating characteristics (ROC) analysis.

Patients and methods: A total of 225 HCC patients were analyzed. We retrospectively examined factors related to overall survival (OS) and progression free survival (PFS) using univariate and multivariate analyses. Subsequently, we performed time-dependent ROC analysis of continuous parameters which were significant in the multivariate analysis in terms of OS and PFS. Total sum of area under the ROC in all time points (defined as TAAT score) in each case was calculated.

Results: Our cohort included 175 male and 50 female patients (median age, 72 years) and included 158 Child-Pugh A and 67 Child-Pugh B patients. The median OS time was 0.68 years, while the median PFS time was 0.24 years. On multivariate analysis, gender, body mass index (BMI), Child-Pugh classification, extrahepatic metastases, tumor burden, aspartate aminotransferase (AST) and alpha-fetoprotein (AFP) were identified as significant predictors of OS and ECOG-performance status, Child-Pugh classification and extrahepatic metastases were identified as significant predictors of PFS. Among three continuous variables (i.e., BMI, AST and AFP), AFP had the highest TAAT score for the entire cohort. In subgroup analyses, AFP had the highest TAAT score except for Child-Pugh B and female among three continuous variables.

Conclusion: In continuous variables, AFP could have higher predictive accuracy for survival in HCC patients undergoing sorafenib therapy.

Comparison of FIB-4 index and aspartate aminotransferase to platelet ratio index on carcinogenesis in chronic hepatitis B treated with entecavir

Aims: We sought to compare the effects of FIB-4 index and aspartate aminotransferase to platelet ratio index (APRI) on hepatocellular carcinoma (HCC) incidence in chronic hepatitis B (CHB) patients undergoing entecavir (ETV) therapy.

Patient and methods: A total of 338 nucleosides analogue therapy naïve CHB patients initially treated with ETV were analyzed. The optimal cutoff points in each continuous variable were determined by receiver operating curve (ROC) analysis. The effects of FIB-4 index and APRI on HCC incidence were compared using time-dependent ROC analysis and factors linked to HCC incidence were also examined using univariate and multivariate analyses.

Results: There were 215 males and 123 females with the median age of 52 years and the median baseline HBV-DNA level of 6.6 log copies/ml. The median follow-up interval after the initiation of ETV therapy was 4.99 years. During the follow-up period, 33 patients (9.8%) developed HCC. The 3-, 5- 7-year cumulative HCC incidence rates in all cases were 4.4%, 9.2% and 13.5%, respectively. In the multivariate analysis, FIB-4 index revealed to be an independent predictor associated with HCC incidence, while APRI was not. In the time-dependent ROC analyses for all cases and for all subgroups analyses stratified by viral status or cirrhosis status, all area under the ROCs in each time point (2-, 3-, 4-, 5-, 6-, and 7-year) of FIB-4 index were higher than those of APRI.

Conclusion: FIB-4 index rather than APRI can be a useful predictor associated with HCC development for CHB patients undergoing ETV therapy.

A predictive model for carcinogenesis in patients with chronic hepatitis B undergoing entecavir therapy and its validation

We created a model to predict the development of liver carcinogenesis in patients with chronic hepatitis B (CHB) undergoing entecavir (ETV) therapy and to validate the accuracy using an independent dataset.A total of 328 CHB subjects were analyzed. Subjects were randomly assigned into 2 groups: the training group (n = 164) and the validation group (n = 164). Using data from the training group, we built a predictive model for liver carcinogenesis by performing univariate and multivariate analyses using variables associated with liver carcinogenesis. We subsequently assessed the applicability of the constructed model in the validation group.The median (range) follow-up periods in the training and the validation groups were 5.03 years (1.03-9.98) and 4.84 years (1.10-9.97), respectively. The proportion of hepatitis B virus-DNA at 24 weeks <1.9 log IU/mL in the training group was 70.7% (116/164), while that in the validation group was 71.3% (117/164). For the entire cohort (n = 328), the median alpha-fetoprotein (AFP) value at 24 weeks (3.45 ng/mL; range, 0.9-102.7 ng/mL) significantly decreased compared to the baseline values (5.55 ng/mL; range, 0.9-1039.5 ng/mL), while the median alanine aminotransferase (ALT) value at 24 weeks (24 IU/mL; range, 6-251 IU/mL) also significantly decreased compared to baseline values (57 IU/mL; range, 7-1450 IU/mL). During the observation period, hepatocellular carcinoma (HCC) developed in 15 (9.1%) patients in the training group and in 17 (10.4%) patients in the validation group. The 3- and 5-year cumulative HCC incidence rates in the entire cohort were 4.48% and 9.52%, respectively. In the multivariate analysis of the training group, age ≥54 years (P = 0.0273), ALT level at 24 weeks (P = 0.0456), and AFP at 24 weeks (P = 0.0485) were found to be significant predictors linked to HCC. Using these independent predictors, the risk for HCC development was well stratified in the validation group (overall significance, P < 0.0001). Similar results were observed in subgroup analyses of patients with or without cirrhosis and HBe antigen positivity.In conclusion, our predictive model was well verified; hence, it may be a promising model for the prediction of the development of liver carcinogenesis in CHB patients undergoing ETV therapy.

Comparison of five staging systems in hepatocellular carcinoma treated with sorafenib: A single-center experience

To the best of our knowledge, none of the prognostic staging systems for hepatocellular carcinoma (HCC) patients who underwent sorafenib therapy is universally adopted or preferred. In the present study, we aimed to compare prognostic ability among five prognostic systems, including the Japan Integrated Staging (JIS) system, the Barcelona Clinic Liver Cancer classification system, the tumor-node-metastasis classification system, the Cancer of the Liver Italian Program scoring system and the Chinese University Prognostic Index (CUPI) scoring system for HCC patients who received sorafenib therapy. A total of 143 HCC patients treated with sorafenib were analysed. We compared prognostic ability among the five prognostic systems using the likelihood ratio (LR) χ² test, linear trend χ² test and concordance index (c-index). Our cohort included 114 men and 29 women. The median patient age was 71 years (range, 45-89 years). A total of 102 patients were classified as Child-Pugh A and 41 as Child-Pugh B, whereas 31 patients (21.7%) had portal vein invasion and 63 (44.1%) extrahepatic metastases. The median survival time was 6.9 months. In the LR χ² test, the CUPI scoring system had the highest value (35.804), followed by the JIS system (17.469). In the linear trend χ² test, the CUPI scoring system had the highest value (17.523), followed by the JIS system (15.819). In addition, the JIS system had the highest value in the 6-month c-index (0.659) as well as in the 1-year c-index (0.674). However, the CUPI classification system had the lowest value in the 1-year c-index (0.590). In conclusion, the JIS system may be an appropriate staging system for HCC patients undergoing sorafenib therapy.

EP4 Receptor-Associated Protein in Macrophages Ameliorates Colitis and Colitis-Associated Tumorigenesis

Prostaglandin E₂ plays important roles in the maintenance of colonic homeostasis. The recently identified prostaglandin E receptor (EP) 4–associated protein (EPRAP) is essential for an anti-inflammatory function of EP4 signaling in macrophages in vitro. To investigate the in vivo roles of EPRAP, we examined the effects of EPRAP on colitis and colitis-associated tumorigenesis. In mice, EPRAP deficiency exacerbated colitis induced by dextran sodium sulfate (DSS) treatment. Wild-type (WT) or EPRAP-deficient recipients transplanted with EPRAP-deficient bone marrow developed more severe DSS-induced colitis than WT or EPRAP-deficient recipients of WT bone marrow. In the context of colitis-associated tumorigenesis, both systemic EPRAP null mutation and EPRAP-deficiency in the bone marrow enhanced intestinal polyp formation induced by azoxymethane (AOM)/DSS treatment. Administration of an EP4-selective agonist, ONO-AE1-329, ameliorated DSS-induced colitis in WT, but not in EPRAP-deficient mice. EPRAP deficiency increased the levels of the phosphorylated forms of p105, MEK, and ERK, resulting in activation of stromal macrophages in DSS-induced colitis. Macrophages of DSS-treated EPRAP-deficient mice exhibited a marked increase in the expression of pro-inflammatory genes, relative to WT mice. By contrast, forced expression of EPRAP in macrophages ameliorated DSS-induced colitis and AOM/DSS-induced intestinal polyp formation. These data suggest that EPRAP in macrophages functions crucially in suppressing colonic inflammation. Consistently, EPRAP-positive macrophages were also accumulated in the colonic stroma of ulcerative colitis patients. Thus, EPRAP may be a potential therapeutic target for inflammatory bowel disease and associated intestinal tumorigenesis.

Inflammatory bowel disease (IBD) is one of the most prevalent and serious gastrointestinal diseases in Western countries and associates with cancer development. EP4 receptor signaling can suppress intestinal inflammation and shows promise as a target for the development of novel therapies for IBD. To date, however, the lack of detailed molecular targets has hampered the development of effective drugs. This study focused on EPRAP, a novel EP4 receptor–associated protein, implicated in its signaling pathway. The generation of EPRAP-gene mutated mice permitted exploration of EPRAP functions in vivo. In addition, EPRAP was localized in stromal macrophages of ulcerative colitis patients. This study revealed that EPRAP in macrophage participates critically in EP4 receptor signaling-mediated inhibition of intestinal inflammation. The macrophage EP4–EPRAP axis thus comprises a novel therapeutic target for IBD.

Hyponatremia in hepatocellular carcinoma complicating with cirrhosis

Background and aims: We aimed to investigate the effect of serum sodium level on survival in hepatocellular carcinoma (HCC) patients complicating with liver cirrhosis (LC).

Methods: A total of 1170 HCC patients with LC were analysed. We classified these patients into three groups according to serum sodium level at HCC diagnosis: group A (n=96); serum sodium ≤135 mmol/L, group B (n=520); 135 mmol/L < serum sodium ≤140 mmol/L, group C (n=554); serum sodium >140 mmol/L. We compared the baseline characteristics and overall survival (OS) among these three groups. Furthermore, we examined the factors linked to OS using univariate and multivariate analyses.

Results: In our results, decreased baseline serum sodium level was significantly associated with Child-Pugh classification and HCC stage along with several laboratory parameters in groups A, B and C. The median follow-up period was 1.1 years in group A, 2.4 years in group B and 3.3 years in group C. The 1-, 3- and 5-year cumulative OS rates in groups A, B and C were 64.8%, 46.9% and 25.7%, respectively, in group A, 85.5%, 60.5% and 41.1%, respectively, in group B and 90.7%, 66.6% and 48.2%, respectively, in group C (P<0.001). The multivariate analyses showed that Child-Pugh classification (P<0.001), HCC stage (P<0.001), serum sodium (P<0.001), aspartate aminotransferase ≥57 IU/L (P=0.002), alkaline phosphatase ≥348 IU/L (P<0.001), alpha-fetoprotein ≥29.2 ng/mL (P=0.019) and des-γ-carboxy prothrombin ≥55 mAU/mL (P<0.001) were significant independent predictors linked to OS.

Conclusion: Lower serum sodium concentration is a useful predictor in HCC patients complicating with LC.

Clinical implication of performance status in patients with hepatocellular carcinoma complicating with cirrhosis

Background and aims: The aims of our study were to elucidate the relationship between baseline characteristics of hepatocellular carcinoma (HCC) patients complicating with liver cirrhosis (LC) and performance status (PS) and to investigate the impact of PS on survival in patients with HCC complicating with LC.

Methods: In a total of 1003 patients diagnosed with HCC complicating with LC, we divided into two groups of PS ≥1 (n=251) and PS 0 (n=752) as evaluated by using the Eastern Cooperative Oncology Group criteria at the time of HCC diagnosis. Baseline characteristics between these two groups were compared. We also performed univariate and multivariate analyses of factors contributing to overall survival (OS).

Results: The median follow-up period was 1.6 years in the PS ≥1 group and 3.1 years in the PS 0 group. The 1-, 3- and 5-year OS rates after each initial therapy for HCC were 90.3%, 67.4% and 49.8%, respectively, in the PS 0 group and 73.4%, 42.0% and 17.7%, respectively, in the PS ≥1 group (P<0.001). A worse PS was significantly associated with age, gender, Child-Pugh classification, HCC stage, Japan Integrated Staging score, initial treatment option for HCC, maximum tumor size, alanine aminotransferase value, hypoalbuminemia, hyperbilirubinemia, renal insufficiency, hyponatremia, prothrombin time prolongation, platelet count and tumor marker level. In multivariate analyses, poorer PS was an independent predictor linked to OS with a hazard ratio of 1.773 (P<0.001).

Conclusions: PS was closely associated with status of HCC patients with LC and could be an important predictor for these populations.

Clinical implication of the preoperative GSA index in ⁹⁹mTc-GSA scintigraphy in hepatitis C virus-related hepatocellular carcinoma

We aimed to examine the relationship between the preoperative GSA index [uptake ratio of the liver to the liver plus heart at 15 min (LHL15) to uptake ratio of the heart at 15 min to that at 3 min (HH15) ratio] calculated from 99mTc‑labeled diethylene triamine pentaacetate-galactosyl human serum albumin (99mTc-GSA) scintigraphy and background liver fibrosis and to investigate whether the GSA index can be a useful predictor in hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC) patients treated with surgical resection (SR). A total of 213 HCV-related HCC patients were analyzed. Receiver operating characteristic (ROC) curve analysis was performed for calculating the area under the ROC (AUROC) for nine noninvasive parameters including GSA index, indocyanine green retention at 15 min, aspartate aminotransferase (AST) to platelet ratio index, FIB-4 index, AST to alanine aminotransferase ratio, serum albumin, total bilirubin, platelet count and prothrombin time for cirrhosis. We also examined predictive factors associated with overall survival (OS) and recurrence-free survival (RFS) after SR in univariate and multivariate analyses. There were 153 males and 60 females with the mean age of 69.9 years. The median observation periods were 2.8 years. The mean maximum tumor size was 4.1 cm. HH15 ranged from 0.452 to 0.897. LHL15 ranged from 0.669 to 0.982. The mean value of the GSA index was 1.41. Among the nine parameters, the GSA index yielded the highest AUROC for cirrhosis with a level of 0.786 at an optimal cut-off value of 1.37 (sensitivity, 65.9%; specificity, 79.0%). In multivariate analyses, the GSA index was an independent predictor (P<0.001) linked to RFS and it had a marginal significance in terms of OS (P=0.074). In conclusion, the preoperative GSA index can be a useful predictor in HCV-related HCC patients treated with SR.

Transcatheter arterial chemoembolization for intermediate-stage hepatocellular carcinoma: clinical outcome and safety in elderly patients

AIM

The aim of our study was to compare clinical outcomes between elderly patients aged ≥75 years (elderly group, n=66) with intermediate hepatocellular carcinoma (HCC) undergoing transcatheter arterial chemoembolization (TACE) and younger patients aged <75 years (control group, n=84) with intermediate HCC undergoing TACE.

METHODS

Clinical outcomes, including overall survival (OS) and tumor response rate at initial therapy, were compared between these two groups.

RESULTS

The median survival time and the 1- and 3-year cumulative OS rates were 2.90 years and 84.1% and 48.0%, respectively, in the elderly group and 2.44 years and 78.2% and 39.3%, respectively, in the control group (p=0.887). The objective response rate in the elderly group was 81.8% (54/66 patients), while that in the control group was 78.6% (66/84 patients) (p=0.227).

CONCLUSION

Elderly patients with intermediate HCC undergoing TACE had a prognosis comparable with that of younger patients with intermediate HCC undergoing TACE.

Clinical efficacy of non-transplant therapies in patients with hepatocellular carcinoma with Child-Pugh C liver cirrhosis

AIM

To compare clinical outcome in patients with Child-Pugh C hepatocellular carcinoma (HCC) treated with non-transplant therapies and those treated with best supportive care.

PATIENTS AND METHODS

A total of 182 patients with HCC with Child-Pugh C cirrhosis were analyzed. Patients were classified into two groups: patients treated with non-transplant therapies (n=113, treated group) and untreated patients (n=69, untreated group). Furthermore, for reducing the bias in patient selection, a propensity score matching analysis was performed (55 pairs).

RESULTS

The median survival time in the treated group was significantly longer than that in the untreated group (1.16 years vs. 0.21 years, p<0.001). After propensity score matching, the median survival time in the treated group remained significantly longer than that in the untreated group (0.95 years vs. 0.17 years, p=0.01).

CONCLUSION

In patients with HCC with Child-Pugh C cirrhosis, those treated with non-transplant therapies might have longer survival than untreated patients.

Deletion of nardilysin prevents the development of steatohepatitis and liver fibrotic changes

Nonalcoholic steatohepatitis (NASH) is an inflammatory form of nonalcoholic fatty liver disease that progresses to liver cirrhosis. It is still unknown how only limited patients with fatty liver develop NASH. Tumor necrosis factor (TNF)-α is one of the key molecules in initiating the vicious circle of inflammations. Nardilysin (N-arginine dibasic convertase; Nrd1), a zinc metalloendopeptidase of the M16 family, enhances ectodomain shedding of TNF-α, resulting in the activation of inflammatory responses. In this study, we aimed to examine the role of Nrd1 in the development of NASH. Nrd1^+/+ and Nrd1^−/− mice were fed a control choline-supplemented amino acid-defined (CSAA) diet or a choline-deficient amino acid-defined (CDAA) diet. Fatty deposits were accumulated in the livers of both Nrd1^+/+ and Nrd1^−/− mice by the administration of the CSAA or CDAA diets, although the amount of liver triglyceride in Nrd1^−/− mice was lower than that in Nrd1^+/+ mice. Serum alanine aminotransferase levels were increased in Nrd1^+/+ mice but not in Nrd1^−/− mice fed the CDAA diet. mRNA expression of inflammatory cytokines were decreased in Nrd1^−/− mice than in Nrd1^+/+ mice fed the CDAA diet. While TNF-α protein was detected in both Nrd1^+/+ and Nrd1^−/− mouse livers fed the CDAA diet, secretion of TNF-α in Nrd1^−/− mice was significantly less than that in Nrd1^+/+ mice, indicating the decreased TNF-α shedding in Nrd1^−/− mouse liver. Notably, fibrotic changes of the liver, accompanied by the increase of fibrogenic markers, were observed in Nrd1^+/+ mice but not in Nrd1^−/− mice fed the CDAA diet. Similar to the CDAA diet, fibrotic changes were not observed in Nrd1^−/− mice fed a high-fat diet. Thus, deletion of nardilysin prevents the development of diet-induced steatohepatitis and liver fibrogenesis. Nardilysin could be an attractive target for anti-inflammatory therapy against NASH.

Effect of treatment with branched-chain amino acids during sorafenib therapy for unresectable hepatocellular carcinoma

AIM

To examine the effect of branched-chain amino acid (BCAA) therapy for patients with unresectable hepatocellular carcinoma (HCC) treated with sorafenib.

METHODS

Seventy-eight subjects with unresectable HCC with a serum level of albumin of 3.5 g/dL or less treated with sorafenib were evaluated. They were classified into two groups: those receiving BCAA granules (n = 34; BCAA group) or a regular diet (n = 44; control group). We compared overall survival and administration period of sorafenib, and analyzed absolute changes in serum levels of albumin during sorafenib therapy in 41 patients who continued sorafenib therapy for 1 month or more with a follow up of more than 3 months.

RESULTS

Median survival time (MST) in BCAA and control groups was 350 and 143 days (P = 0.007), respectively. Median administration period of sorafenib in the two groups was 59 and 41 days (P = 0.018). In the 41 patients described above, at 1 month, there was no significant change in the serum level of albumin between the two groups, but at 3 months, the difference in the absolute change in the serum level of albumin in the two groups reached significance (P = 0.023). In these subgroup analyses, the administration period of sorafenib as well as the MST in the BCAA group were significantly longer than those in the control group (P = 0.020 and = 0.004).

CONCLUSION

BCAA treatment during sorafenib therapy in HCC patients is useful for maintaining hepatic functional reserve, which may help to avoid early discontinuance of sorafenib therapy and improve survival.

[A case of α-fetoprotein-producing hepatoid adenocarcinoma of the stomach with spontaneous rupture of multiple liver metastases]

An 85-year-old man with epigastric pain and anorexia was admitted to our hospital. His serum α-fetoprotein (AFP) and protein induced by vitamin K absence or antagonist II (PIVKA II) levels were markedly elevated. Gastrointestinal endoscopy revealed a large mass near the fundus, and computed tomography revealed multiple liver tumors. Intraperitoneal bleeding followed rupture of a liver tumor and was successfully stopped by transarterial embolization; however, regrowth of multiple tumors followed, resulting in liver failure and death within a short period. Autopsy revealed hepatoid adenocarcinomas originating in the stomach that had metastasized to the liver. Hepatoid adenocarcinomas are hypervascular, rapidly growing tumors that may result in the spontaneous rupture of metastatic liver lesions. Transarterial embolization may be a feasible option for the treatment of these ruptured tumors.

Impact of pretreatment serum cholinesterase level in unresectable advanced hepatocellular carcinoma patients treated with sorafenib

The value of serum cholinesterase (ChE) level as a predictive marker in sorafenib therapy for advanced hepatocellular carcinoma (HCC) has not yet been investigated. The present retrospective study therefore analyzed the impact of the serum ChE level in 93 patients with advanced HCC treated with sorafenib. Patients were categorized into two groups: group A with pretreatment serum ChE ≥140 IU/l (n=46) and group B with pretreatment serum ChE <140 IU/l (n=47). The correlation between clinicopathological findings, including serum ChE level, and overall survival (OS) and liver damage during sorafenib therapy was investigated. The median OS of the patients was 275 days, while OS was markedly higher in group A compared to group B (P=0.002). In 70 Child-Pugh A patients, serum ChE level was a significant prognostic predictor in multivariate analysis [P=0.019, hazard ratio (HR) =2.612; 95% confidence interval (CI), 1.174-5.810]. During sorafenib treatment, 22 patients developed liver dysfunction of grade 3 or higher. Only two group A patients (4.3%) developed liver dysfunction, compared to 20 group B patients (42.6%) (P<0.001). Multivariate analysis demonstrated that the pretreatment serum ChE level was the strongest predictor of liver damage (P=0.002, HR=0.061, 95% CI: 0.010-0.373), indicating serum ChE <140 IU/l to be the only independent predictor associated with severe liver function damage during sorafenib treatment in 70 patients with grade A Child-Pugh (P= 0.016; HR= 0.122; 95% CI, 0.022-0.676). In conclusion, lower serum ChE level is a significant predictor of poor prognosis and severe liver damage in HCC patients treated with sorafenib. Advanced HCC patients with lower serum ChE levels, including those with a Child-Pugh A pretreatment liver function score, should be given sorafenib therapy with caution.

Dclk1 distinguishes between tumor and normal stem cells in the intestine

There is great interest in tumor stem cells (TSCs) as potential therapeutic targets; however, cancer therapies targeting TSCs are limited. A drawback is that TSC markers are often shared by normal stem cells (NSCs); thus, therapies that target these markers may cause severe injury to normal tissues. To identify a potential TSC-specific marker, we focused on doublecortin-like kinase 1 (Dclk1). Dclk1 was reported as a candidate NSC marker in the gut, but recent reports have implicated it as a marker of differentiated cells (for example, Tuft cells). Using lineage-tracing experiments, we show here that Dclk1 does not mark NSCs in the intestine but instead marks TSCs that continuously produce tumor progeny in the polyps of Apc(Min/+) mice. Specific ablation of Dclk1-positive TSCs resulted in a marked regression of polyps without apparent damage to the normal intestine. Our data suggest the potential for developing a therapy for colorectal cancer based on targeting Dclk1-positive TSCs.

Dclk1 distinguishes between tumor and normal stem cells in the intestine

There is great interest in tumor stem cells (TSCs) as potential therapeutic targets; however, cancer therapies targeting TSCs are limited. A drawback is that TSC markers are often shared by normal stem cells (NSCs); thus, therapies that target these markers may cause severe injury to normal tissues. To identify a potential TSC-specific marker, we focused on doublecortin-like kinase 1 (Dclk1). Dclk1 was reported as a candidate NSC marker in the gut, but recent reports have implicated it as a marker of differentiated cells (for example, Tuft cells). Using lineage-tracing experiments, we show here that Dclk1 does not mark NSCs in the intestine but instead marks TSCs that continuously produce tumor progeny in the polyps of Apc(Min/+) mice. Specific ablation of Dclk1-positive TSCs resulted in a marked regression of polyps without apparent damage to the normal intestine. Our data suggest the potential for developing a therapy for colorectal cancer based on targeting Dclk1-positive TSCs.

Nardilysin and ADAM proteases promote gastric cancer cell growth by activating intrinsic cytokine signalling via enhanced ectodomain shedding of TNF-α

Nardilysin (NRDc), a metalloendopeptidase of the M16 family, promotes ectodomain shedding of the precursor forms of various growth factors and cytokines by enhancing the protease activities of ADAM proteins. Here, we show the growth-promoting role of NRDc in gastric cancer cells. Analyses of clinical samples demonstrated that NRDc protein expression was frequently elevated both in the serum and cancer epithelium of gastric cancer patients. After NRDc knockdown, tumour cell growth was suppressed both in vitro and in xenograft experiments. In gastric cancer cells, NRDc promotes shedding of pro-tumour necrosis factor-alpha (pro-TNF-α), which stimulates expression of NF-κB-regulated multiple cytokines such as interleukin (IL)-6. In turn, IL-6 activates STAT3, leading to transcriptional upregulation of downstream growth-related genes. Gene silencing of ADAM17 or ADAM10, representative ADAM proteases, phenocopied the changes in cytokine expression and cell growth induced by NRDc knockdown. Our results demonstrate that gastric cancer cell growth is maintained by autonomous TNF-α–NF-κB and IL-6–STAT3 signalling, and that NRDc and ADAM proteases turn on these signalling cascades by stimulating ectodomain shedding of TNF-α.

Chitinase 3-like 1 promotes macrophage recruitment and angiogenesis in colorectal cancer

Chitinase 3-like 1 (CHI3L1), one of mammalian members of the chitinase family, is expressed in several types of human cancer, and elevated serum level of CHI3L1 is suggested to be a biomarker of poor prognosis in advanced cancer patients. However, the overall biological function of CHI3L1 in human cancers still remains unknown. Studies were performed to characterize the role of CHI3L1 in cancer pathophysiology utilizing human colorectal cancer samples and human cell lines. Plasma protein and tissue mRNA expression levels of CHI3L1 in colorectal cancer were strongly upregulated. Immunohistochemical analysis showed that CHI3L1 was expressed in cancer cells and CHI3L1 expression had a significant association with the number of infiltrated macrophages and microvessel density. By utilizing trans-well migration and tube formation assays, overexpression of CHI3L1 in SW480 cells (human colon cancer cells) enhanced the migration of THP-1 cells (human macrophage cells) and HUVECs (human endothelial cells), and the tube formation of HUVECs. The knockdown of CHI3L1 by RNA interference or the neutralization of CHI3L1 by anti-CHI3L1 antibody displayed strong suppression of CHI3L1-induced migration and tube formation. Cell proliferation assay showed that CHI3L1 overexpression significantly enhanced the proliferation of SW480 cells. ELISA analysis showed that CHI3L1 increased the secretion of inflammatory chemokines, IL-8 and MCP-1, from SW480 cells through mitogen-activated protein kinase (MAPK) signaling pathway. Both neutralization of IL-8 or MCP-1 and inhibition or knockdown of MAPK in SW480 cells significantly inhibited CHI3L1-induced migration and tube formation. In a xenograft mouse model, overexpression of CHI3L1 in HCT116 cells (human colon cancer cells) enhanced the tumor growth as well as macrophage infiltration and microvessel density. In conclusion, CHI3L1 expressed in colon cancer cells promotes cancer cell proliferation, macrophage recruitment and angiogenesis. Thus, the inhibition of CHI3L1 activity may be a novel therapeutic strategy for human colorectal cancer.

COX-2 inhibition alters the phenotype of tumor-associated macrophages from M2 to M1 in ApcMin/+ mouse polyps

Macrophages are a major component of tumor stroma. Tumor-associated macrophages (TAMs) show anti- (M1) or protumor (M2) functions depending on the cytokine milieu of the tumor microenvironment. Cyclooxygenase-2 (COX-2) is constitutively expressed in a variety of tumors including colorectal cancer. TAMs are known to be a major source of COX-2 in human and mice intestinal tumors. COX-2 inhibitor reduces the number and size of intestinal adenomas in familial adenomatous polyposis patients and Apc(Min/+) mice. Although COX-2 inhibitor is thought to regulate cancer-related inflammation, its effect on TAM phenotype remains unknown. Here, we examined the effects of COX-2 inhibition on TAM phenotype and cytokine expression both in vivo and in vitro. Firstly, the selective COX-2 inhibitor celecoxib changed the TAM phenotype from M2 to M1, in proportion to the reduction in number of Apc(Min/+) mouse polyps. Concomitantly, the expression of M1-related cytokine interfron (IFN)-γ was significantly upregulated by celecoxib, although the M2-related cytokines interleukin (IL)-4, IL-13 and IL-10 were not significantly altered. Secondly, IFN-γ treatment attenuated M2 phenotype of mouse peritoneal macrophages and oriented them to M1 even in the presence of M2-polarizing cytokines such as IL-4, IL-13 and IL-10. Thus, our results suggest that COX-2 inhibition alters TAM phenotype in an IFN-γ-dependent manner and subsequently may reduce intestinal tumor progression.

Glycosylation and palmitoylation of Wnt-3a are coupled to produce an active form of Wnt-3a

Wnt-3a is a representative ligand that activates the beta-catenin-dependent pathway in Wnt signaling and is modified with glycans and palmitate. In this study, we analyzed the relationship between glycosylation and lipidation of Wnt-3a. Secretion of a Wnt-3a mutant that lacks glycosylation (Wnt-3a NQ) was impaired. Wnt-3a C77A, which lacks palmitoylation at Cys77, was secreted with similar efficiency to wild-type Wnt-3a (Wnt-3a WT), but did not induce the internalization of low-density lipoprotein receptor-related protein 6 (LRP6). Furthermore, removal of palmitate from Wnt-3a suppressed the ability to bind to its receptors Frizzled8 and LRP6. Wnt-3a C77A was glycosylated to an extent similar to Wnt-3a WT, while Wnt-3a NQ was not modified with palmitate. Expression of porcupine, which is a putative acyltransferase, enhanced palmitoylation of Wnt-3a WT greatly, but that of Wnt-3a NQ slightly. While Wnt-3a WT was present in both the endoplasmic reticulum (ER) and Golgi, Wnt-3a NQ was located to the ER only. Furthermore, Wnt-3a was not palmitoylated but was glycosylated in the cells treated with Brefeldin A, which inhibits transport of vesicles from the ER to the Golgi. These results indicate that glycosylation of Wnt-3a precedes palmitoylation and that both modifications are necessary for secretion of an active Wnt-3a.

Caveolin is necessary for Wnt-3a-dependent internalization of LRP6 and accumulation of beta-catenin

beta-catenin-mediated Wnt signaling is critical in animal development and tumor progression. The single-span transmembrane Wnt receptor, low-density lipoprotein receptor-related protein 6 (LRP6), interacts with Axin to promote the Wnt-dependent accumulation of beta-catenin. However, the molecular mechanism of receptor internalization and its impact on signaling are unclear. Here, we present evidence that LRP6 is internalized with caveolin and that the components of this endocytic pathway are required not only for Wnt-3a-induced internalization of LRP6 but also for accumulation of beta-catenin. Overall, our data suggest that Wnt-3a triggers the interaction of LRP6 with caveolin and promotes recruitment of Axin to LRP6 phosphorylated by glycogen synthase kinase-3beta and that caveolin thereby inhibits the binding of beta-catenin to Axin. Thus, caveolin plays critical roles in inducing the internalization of LRP6 and activating the Wnt/beta-catenin pathway. We also discuss the idea that distinct endocytic pathways correlate with the specificity of Wnt signaling events.