Clinical factors associated with the therapeutic efficacy of atezolizumab plus bevacizumab in patients with unresectable hepatocellular carcinoma: A multicenter prospective observational study

The treatment efficiency and predictors of atezolizumab plus bevacizumab therapy for unresectable hepatocellular carcinoma in real-world practice have not been established. This study aimed to assess the efficacy and safety of atezolizumab plus bevacizumab and to investigate predictors of progression-free survival and overall survival. Patients with unresectable hepatocellular carcinoma treated with atezolizumab plus bevacizumab therapy in 19 hospitals were enrolled before treatment and observed prospectively. The outcomes of 222 patients in this cohort were analyzed. The objective response rate and disease control rate were 22.0% and 70.6%, respectively, whereas the median progression-free survival was 5.7 months. Independent risk factors for shortened progression-free survival were younger age (<75 years; 3.9 months vs. 8.6 months), higher number of intrahepatic tumors (≥5; 4.0 months vs. 7.9 months), macrovascular invasion (2.3 months vs. 6.7 months), and higher neutrophil-to-lymphocyte ratio (≥3.03; 3.0 months vs. 7.8 months). The median overall survival was not reached; however, independent risk factors for shortened overall survival were absence of hyperlipidemia, higher number of intrahepatic tumors (≥5), macrovascular invasion, higher α-fetoprotein level (≥400 ng/mL), worse Child-Pugh score (≥6), and higher neutrophil-to-lymphocyte ratio (≥3.03). Severe adverse events (grade ≥3) were observed in 96 patients (36.0%), with proteinuria being the most frequent. In conclusion, patients with older age, lower number of intrahepatic tumors, absent macrovascular invasion, and lower neutrophil-to-lymphocyte ratio are expected to have better progression-free survival with atezolizumab plus bevacizumab therapy for unresectable hepatocellular carcinoma.

Pretreatment with antibiotics is associated with reduced therapeutic response to atezolizumab plus bevacizumab in patients with hepatocellular carcinoma

AIM

Alterations in microbial composition of gut microbiota due to antibiotics (ATB) may lead to resistance to immune checkpoint inhibitors (ICIs). This study aimed to assess the impact of ATB use on therapeutic response in patients with hepatocellular carcinoma (HCC) receiving atezolizumab plus bevacizumab.

METHODS

This study retrospectively analyzed 105 patients with HCC treated with atezolizumab plus bevacizumab as a primary systemic therapy from prospectively-registered, multicenter, cohorts. Nineteen patients who received prior ATB were included in the ATB (+) group; 86 patients who did not receive prior ATB were included in the ATB (-) group. The therapeutic outcomes were compared between the two groups.

RESULTS

Most of the patients' baseline characteristics were not significantly different between the two groups. The objective response rates according to the Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v1.1) (30.1% vs. 11.1%; p = 0.143) and modified RECIST (mRECIST) (44.6% vs. 27.8%; p = 0.190) were not significantly different between the ATB (-) and ATB (+) groups. The disease control rates were higher in the ATB (-) group than in the ATB (+) group according to RECIST v1.1 (74.7% vs. 44.4%; p = 0.012) and mRECIST (78.3% vs. 50.0%; p = 0.020). Prior ATB use was found to be independently associated with radiological progressive disease of the first therapeutic assessment. The median progression-free survival according to RECIST v1.1 (9.1 months vs. 3.0 months; p = 0.049) and mRECIST (9.1 months vs. 3.0 months; p = 0.036), and overall survival (not reached vs. 11.4 months; p = 0.015) were longer in the ATB (-) group than in the ATB (+) group.

CONCLUSIONS

Prior ATB use was associated with reduced therapeutic responses in patients with HCC receiving atezolizumab plus bevacizumab.

Thrombospondin-2 as a Predictive Biomarker for Hepatocellular Carcinoma after Hepatitis C Virus Elimination by Direct-Acting Antiviral

We evaluated the value of secreted glycoprotein thrombospondin-2 (TSP-2) to predict hepatocellular carcinoma (HCC) occurrence in chronic hepatitis C (CHC) patients after Hepatitis C virus (HCV) elimination by direct-acting antiviral agents (DAAs). A total of 786 CHC patients without an HCC history who achieved a sustained virological response (SVR) with DAAs were randomly assigned 2:1, with 524 patients as the derivation cohort and 262 patients as the validation cohort. Serum TSP-2 levels at the end of treatment were measured by enzyme-linked immunosorbent assay (ELISA). In the derivation cohort, the cumulative HCC rate was significantly higher in the high TSP-2 group than in the low TSP-2 group. Multivariate Cox proportional hazards analysis revealed that TSP-2, α-fetoprotein (AFP), and the fibrosis-4 (FIB-4) index were independent HCC risk factors. The area under the receiver operating characteristic curve (AUROC) of the score calculated from these three factors (AFT score) for predicting HCC was 0.83, which was significantly higher than that of each factor alone (TSP-2: 0.70, AFP: 0.72, FIB-4: 0.69). The AFT score was used to stratify patients according to the risk of HCC occurrence in the validation cohort. Lastly, in patients with a FIB-4 index < 3.25, the serum TSP-2 levels could be used to identify those patients with a high risk of HCC occurrence. Serum TSP-2 levels are a predictive biomarker of HCC occurrence in CHC patients after HCV elimination by DAA treatment. The AFT score using TSP-2, AFP, and the FIB-4 index may identify those who require HCC surveillance.

Effect of sofosbuvir and velpatasvir therapy on clinical outcome in hepatitis C virus patients with decompensated cirrhosis

AIM

To determine the impact of direct-acting antiviral therapy on the long-term prognosis of decompensated cirrhotic patients.

METHODS

A total of 37 patients with hepatitis C virus-induced decompensated cirrhosis treated with sofosbuvir and velpatasvir (SOF/VEL group) were prospectively enrolled. For historical control, 65 hepatitis C virus-positive decompensated cirrhotic patients who did not receive direct-acting antiviral therapy were included (control group). The incidence rates of hepatocellular carcinoma (HCC), decompensated events with hospitalization, and overall survival were compared between both groups.

RESULTS

A total of 41 patients experienced decompensated events during 15.0 months in the control group, and six patients during 21.6 months in the SOF/VEL group. The cumulative incidence rates of decompensated events after 2 years were significantly higher in the control group (53.1%) than in the SOF/VEL group (14.5%; p < 0.001). A total of 27 patients died within 22.0 months in the control group, and three patients died within 25.6 months in the SOF/VEL group. The overall survival rates after 2 years were significantly lower in the control group (67.6%) than in the SOF/VEL group (91.3%; p = 0.010). A total of 13 patients in the control group developed HCC during 15.8 months, and 10 patients during 17.3 months in the SOF/VEL group. The HCC incidence rates after 2 years were 20.3% and 29.6% in the control and SOF/VEL groups, respectively, with no significant difference (p = 0.327).

CONCLUSIONS

SOF/VEL therapy may suppress the development of decompensated events and improve the prognosis in decompensated cirrhotic patients; however, the incidence of HCC remains prevalent in these patients irrespective of SOF/VEL therapy.

Prognostic impact of worsening of esophageal varices after balloon-occluded retrograde transvenous obliteration

BACKGROUND AND AIM

Balloon-occluded retrograde transvenous obliteration (BRTO) is widely performed for treating gastric varices (GVs). However, worsening of esophageal varices (EVs) can be observed after BRTO. This study aimed to investigate the impact of EV worsening on prognosis after BRTO.

METHODS

Overall, 258 patients who underwent initial BRTO for GV treatment between January 2004 and May 2019 at 12 institutions were retrospectively registered.

RESULTS

Technical success was achieved in 235 patients (91.1%). Based on the exclusion criteria, 37 patients were excluded, and 198 were evaluated. The cumulative worsening rates of EVs at 1, 2, and 3 years were 39.0%, 59.4%, and 68.4%, respectively. In the univariate Cox proportional hazards model, sex, EV size, history of EV treatment, left gastric vein dilatation, platelet count, aspartate transaminase (AST), alanine aminotransferase (ALT), total bilirubin, albumin, albumin-bilirubin score, prothrombin time-international normalized ratio, fibrosis-4 index, AST to platelet ratio index, and spleen width were significantly associated with worsening of EV after BRTO. Multivariate analysis showed that sex (adjusted hazard ratio [aHR] 1.72; 95% confidence interval [CI] 1.03-2.86; P = 0.04), left gastric vein dilatation (aHR 1.90; 95% CI 1.17-3.10; P = 0.01), ALT (aHR 1.01; 95% CI 1.00-1.03; P = 0.02), albumin (aHR 0.61; 95% CI 0.43-0.87; P < 0.01), and spleen width (aHR 1.02; 95% CI 1.01-1.03; P < 0.01) were independent risk factors for worsening of EV after BRTO. Patients with EV worsening within 1 year after BRTO had a significantly worse prognosis than the other patients (P = 0.007).

CONCLUSIONS

Early worsening of EV after BRTO was associated with poor prognosis after BRTO.

Clinical course of hepatitis C virus-positive patients with decompensated liver cirrhosis in the era of direct-acting antiviral treatment

AIM

The aim of the present study was to investigate the clinical course in hepatitis C virus (HCV)-positive patients with decompensated liver cirrhosis after direct-acting antivirals (DAAs) have been used for HCV infection.

METHODS

This multicenter study prospectively analyzed a registered cohort composed of 73 HCV-positive patients with decompensated cirrhosis who attended our 11 institutions between January 2018 and July 2018. Prognoses, including changes in the liver reserve, hepatocellular carcinoma (HCC), decompensation events, and survival, were analyzed up to July 2020, as was the initiation of DAA treatment.

RESULTS

Sixty-four (87.7%) and nine (12.3%) patients had Child-Pugh class (C-P) B and C at baseline, respectively. Within 2 years after enrollment, 17 patients (23.3%) received treatment with DAAs, and 31 patients (42.5%) developed uncontrolled HCC, switched to palliative care, or died. Patients who received DAA treatment were significantly younger and had significantly higher alanine aminotransferase levels and lower platelet counts than the patients who did not receive DAA treatment. The rates of overall survival, cumulative HCC occurrence, and cumulative hospitalization for any hepatic decompensation event at 2 years were 64.8%, 13.1%, and 65.6%, respectively. Overall survival was significantly shorter and the HCC occurrence and hospitalization rates were significantly higher in C-P C patients than in C-P B patients.

CONCLUSIONS

Among HCV-positive patients with decompensated cirrhosis, approximately one-fourth received DAA treatment, but more than 40% of the patients lost the opportunity for treatment with DAAs.

Prognostic Factors for Patients With a Large Number of Hepatocellular Carcinoma Nodules

Background

Methods

Results

Conclusions

Development of a thrombus in the superior mesenteric artery associated with sequential therapy with tyrosine kinase inhibitors for hepatocellular carcinoma

Tyrosine kinase inhibitors (TKIs) are widely used for systemic chemotherapy of hepatocellular carcinoma (HCC). Arterial thromboembolism (ATE) has been reported to be an adverse event associated with TKI therapy, but its incidence is rare. Here, we report a case of an HCC patient who developed a thrombus in the superior mesenteric artery (SMA) while on TKI therapy. The patient was a 78-year-old Japanese man with hepatitis C virus-associated HCC with multiple nodules. Several sessions of transarterial chemoembolization therapy caused him to become refractory to the treatment. Sorafenib and regorafenib therapy had also been previously performed, but his disease continued to progress gradually. Therefore, we started lenvatinib therapy. When a contrast-enhanced computed tomography (CT) examination was performed 2 months later, we found a thrombus in the SMA. Retrospective analysis of the CT images revealed that the thrombus formed during the sorafenib-regorafenib sequential therapy and it developed rapidly, especially during the lenvatinib therapy. An HCC patient developed a thrombus in the SMA during TKI therapy. The incidence of ATE is rare in TKI treatment; however, long-term or sequential TKI therapy may increase the frequency of ATE. Further study is needed.

Abstract P1-07-23: The quality and quantity of visceral fat tissue are associated with insulin resistance and survival outcome after chemotherapy for patients with early-stage breast cancer

Background: Obesity and insulin resistance are associated with inferior levels of chemosensitivity and overall prognosis for breast cancer (BC) treatment. Recent studies suggest that the quality and quantity of visceral adipose tissue (VAT) play a significant role in adipocyte function, and are related to insulin resistance. We therefore tested the hypothesis that high amount and low quality of VAT worsen treatment outcomes via insulin resistance mechanisms.

Patients and Methods: We examined two independent studies: a cross-sectional study (cohort 1) and a retrospective study (cohort 2). Cohort 1 included 106 women with early-stage BC who were undergoing surgery. Patients with normal weight (17.5&lt; body mass index [BMI, kg/m2] ≤25, n = 53) and overweight/obese patients (BMI &gt;25, n = 53) were selected by a pair-matching method. Insulin resistance was evaluated by HOMA-R: fasting insulin (microU/L) × fasting glucose (nmol/L)/22.5. And insulin-like growth factor (IGF) family including IGF-1 and IGF-binding protein 3 (IGFBP3) were measured before beginning treatment. The amounts of visceral fat (aVAT) was measured by 3-dimensional volumetric software using the stocked computed tomography (CT) imaging data. The quality of VAT was assessed based on the mode value of CT Hounsfield Unit of VAT (VAT-HU) at navel level of CT axial view. The association between the former variables and the quality and quantity of VAT was analyzed. Cohort 2 included 271 patients who received chemotherapy in the neo-adjuvant (NAC) or adjuvant setting. Imaging analysis was performed in the same way, and the association between those values and survival outcome after chemotherapy was analyzed by retrospective chart review.

Results: In cohort 1, aVAT was significantly correlated with serum insulin and HOMA-R levels (Pearson's R 0.44 and 0.42, respectively; P&lt;0.05). On comparing the two groups divided by BMI, the levels of IGF-1 and IGFBP3 were not significantly different between the normal weight and the overweight/obese groups (P = 0.31 and 0.77, respectively). However, the overweight/obese group demonstrated significantly higher HOMA-R (P&lt;0.05). In cohort 2, aVAT was significantly correlated with BMI (P&lt;0.05). In a multivariate analysis, pathological complete responses were not associated with aVAT (P = 0.60). After a median follow-up of 112 months, tertile stratification revealed that the third tertile of aVAT had a significantly shorter distant disease free survival (DDFS) in the NAC setting (p&lt;0.05). When adjusted by covariates in the Cox proportional regression model, aVAT and VAT-HU demonstrated significant contribution to a worsened DDFS ([p&lt;0.05, hazard ratio {HR} 1.39; 95% confidence interval {CI} 1.11 to 1.75] and [p&lt;0.05, HR 1.20, 95% CI 1.01 to 1.43], respectively).

Conclusions: Our study found that high amounts and low quality of VAT worsen treatment outcomes. Furthermore, we found that insulin resistance was related to those two factors. Although further validation is needed, our present work suggests the importance of evaluating the quality and quantity of visceral fat for estimating insulin resistance and treatment outcomes after chemotherapy for patients with early-stage BC.

Citation Format: Iwase T, Sangai T, Nagashima T, Sakakibara M, Fujimoto H, Sawabe Y, Nagashima K, Otsuka M. The quality and quantity of visceral fat tissue are associated with insulin resistance and survival outcome after chemotherapy for patients with early-stage breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-07-23.

Two-step progression of varenicline-induced autoimmune hepatitis

We describe a rare case of drug-induced hepatitis due to the smoking cessation agent varenicline in a 46-year-old Asian woman. The liver injury progressed in two steps. First, the liver injury started in the absence of viral/autoimmune responses, and withdrawal of varenicline lowered the increase in the levels of liver enzymes immediately. Such findings suggested varenicline-induced liver injury. Second, hepatitis recurred in association with conversion of antinuclear antibody from negative to positive about 8 weeks after the initial episode. Histology upon recurrence of liver injury revealed interface hepatitis with lymphocytic and lymphoplasmacytic portal inflammatory infiltrates extending into lobules. Such findings suggested autoimmune hepatitis. Corticosteroid treatment was effective for recurrent hepatitis. The clinical course suggests that varenicline caused drug-induced liver injury and subsequent autoimmune hepatitis. Some autoimmune changes were probably involved in the mechanism of varenicline-induced liver injury.

Prospective Comparison of Gd-EOB-DTPA-Enhanced MRI with Dynamic CT for Detecting Recurrence of HCC after Radiofrequency Ablation

BACKGROUND

We prospectively compared the efficacy of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) with that of dynamic multidetector computed tomography (MDCT) for detection of recurrent hypervascular hepatocellular carcinoma (HCC) after radiofrequency ablation (RFA).

METHODS

Institutional review board approval and written informed consent were obtained for this multicenter study. Ninety-seven HCC patients treated with curative RFA underwent both Gd-EOB-DTPA-enhanced MRI and dynamic MDCT every 3-4 months. HCC diagnosis was made based on the typical enhancement pattern of HCC on MRI and/or CT by on-site consensus reading. Two blinded observers independently assessed image datasets to compare diagnostic accuracy, sensitivity, specificity, and the areas under the receiver operating characteristic curve (AUROC).

RESULTS

Recurrence was observed in 48 of 97 patients. Among these, 22 were diagnosed by both Gd-EOB-DTPA-enhanced MRI and MDCT; the remainder were diagnosed by only one of these 2 modalities. Recurrence was diagnosed in more patients by Gd-EOB-DTPA-enhanced MRI than by MDCT (44 vs. 26 patients, p < 0.001). Patient-based analysis revealed that the accuracy, sensitivity, and AUROC of Gd-EOB-DTPA-enhanced MRI were significantly higher than those of MDCT for both observers (p < 0.005). The AUROC of Gd-EOB-DTPA- enhanced MRI and MDCT was 0.95 and 0.76 for observer 1 and 0.90 and 0.74 for observer 2, respectively. The κ values for MRI and MDCT were 0.83 and 0.70, respectively.

CONCLUSIONS

Compared with dynamic MDCT, Gd-EOB-DTPA-enhanced MRI had higher diagnostic accuracy and sensitivity for detection of recurrent hypervascular HCC and may be a better tool for following patients after RFA.

The Effectiveness of a Liver Disease Education Class for Providing Information to Patients and Their Families

Background

We have been conducting liver disease education classes regularly in our hospital for the purpose of providing health information to patients and their families.

Methods

In order to evaluate the effectiveness of these classes, we conducted a questionnaire survey of patients and family members who attended the classes held three times in 2012. The cumulative total number of participants was 80 (49 patients, 26 family members, and five others). The classes focused on the following areas: 1) prevention of hepatic cancer; 2) treatment of hepatic cancer; 3) iron restriction diet for hepatitis C patients; and 4) importance of branched-chain amino acid preparations. Self-evaluation of knowledge in these areas was based on a four-point scale.

Results

A comparison of knowledge levels between the patients and their family members revealed no statistically significant differences. Therefore, subsequent analyses were performed by combining the patients and their families into one group. The knowledge level of the participants increased with the number of class attendances; that is, the more often they attended, the more they accumulated knowledge (Kruskal-Wallis test: P < 0.0001; P = 0.0368; P = 0.0021; and P < 0.0001). In addition, the results of the questionnaire administered immediately before and after the education class showed significant improvement in the knowledge level for each area.

Conclusion

The results of this study indicate the liver disease education class to be effective for improving the knowledge of patients and their families. The importance of repeated information provision was also demonstrated.

Quick and stable parallel puncture of hepatic tumors using a double-barreled needle direction system for ultrasound-guided bipolar radiofrequency ablation

AIM

In bipolar radiofrequency ablation (RFA) therapy, insertion of multiple needles at appropriate points on a target is difficult. The aim of our study was to evaluate a simplified method for multi-electrode insertion using a newly developed double-barreled needle guidance system for percutaneous RFA of hepatic tumors.

METHODS

RFA using two bipolar electrodes was performed in 15 consecutive patients (nine men, six women; mean age, 72.0 ± 8.2 years) with a solitary small (≤3 cm) hepatic tumor. The first five nodules were treated using the conventional puncture method with the standard attachment, then 10 nodules were ablated using the parallel puncture method with the double-barreled attachment. The times required for double-needle placement and the shapes of the ablated areas were compared between the two puncture methods.

RESULTS

The parallel puncture method required a shorter time for double-needle placement than the conventional method (12 s [range, 8-24] vs 96 s [range, 50-240]; P = 0.0003), and allowed continuous observation of the tip of all needles and the size of the ablated area as it increased until completion of the ablation. The method also provided a stable ellipsoidal ablated area. The median height, width and thickness were 30 mm (range, 22-34), 30 mm (range, 21-33) and 20 mm (range, 7-25), respectively, using 20-mm electrodes, and 34 mm (range, 32-41), 36 mm (range, 35-38) and 24 mm (range, 23-24), respectively, using 30-mm electrodes.

CONCLUSION

The parallel puncture method may be a feasible procedure for multi-needle RFA therapy.

Computed tomography during hepatic arteriography pattern may predict hepatocellular carcinoma recurrence following transarterial chemoembolization

AIM

This study aimed to determine the role of morphological patterns seen on imaging in predicting hepatocellular carcinoma recurrence following transarterial chemoembolization therapy.

METHODS

Forty-seven patients from a single center who underwent transarterial chemoembolization to treat unresectable hepatocellular carcinomas between January 2011 and June 2012 were included in this study. We investigated whether the two pretreatment findings on computed tomography during hepatic arteriography (pattern 1, the single nodule pattern; pattern 2, at least one nodule showing the contiguous multinodular pattern) and other factors (age, sex, etiology, serum total bilirubin, serum albumin, prothrombin time, platelet count, serum level of protein induced by vitamin K absence/antagonist-II, serum α-fetoprotein, number of previous treatments for hepatocellular carcinoma, tumor number and maximum tumor size, presence of hypovascular lesions) could predict post-treatment recurrence.

RESULTS

In a univariate analysis using Cox's proportional hazards model, serum total bilirubin, the serum level of protein induced by vitamin K absence/antagonist-II (≤100 vs ≥101 mAU/mL), tumor morphology (pattern 1 vs 2) and tumor number (≤3 vs ≥4) showed statistical significance (≤0.05). In a multivariate analysis of these factors, morphology and tumor number showed significance. According to Kaplan-Meier estimation, the cumulative disease-free survival rates were significantly lower in patients with four or more lesions than in those with three or less lesions and in patients showing pattern 2 than in those showing pattern 1.

CONCLUSION

Patients with pattern 2 hepatocellular carcinoma and/or four or more lesions may have a relatively high recurrence rate after transarterial chemoembolization.

Factors related to shift from hepatic borderline lesion to overt HCC diagnosed by CT

BACKGROUND/AIMS

Factors contributing to the shift from the hepatic borderline lesion to overt hepatocellular carcinoma (HCC) were investigated.

METHODOLOGY

Ninety-five borderline nodules from 69 patients were followed-up for 6-55 (median 24) months. The borderline lesion was diagnosed when the CT image demonstrated low density in the portal phase and lacked enhancement in the arterial phase.

RESULTS

The shift to overt HCC was seen in 32 nodules from 27 patients. Using multivariate analysis, only size was a significant factor contributing to the shift to overt HCC (p = 0.009). The cumulative incidence of the shift to overt HCC was higher in nodules of ≥13 mm in size than in those of < 13 mm (p = 0.034). Among nodules of ≥13 mm, nodules showing iso density in the arterial phase and low density in the portal phase had a higher cumulative incidence of the shift to overt HCC than those showing low density in the arterial and portal phases on CT (p=0.007).

CONCLUSIONS

In hepatic borderline nodules diagnosed by CT, greater size, and iso density in the arterial phase and low density in the portal phase may be risk factors associated with the shift to overt HCC.

From likes to dislikes: conditioned taste aversion in the great pond snail (Lymnaea stagnalis)

The neural circuitry comprising the central pattern generator (CPG) that drives feeding behavior in the great pond snail (Lymnaea stagnalis (L., 1758)) has been worked out. Because the feeding behavior undergoes associative learning and long-term memory (LTM) formation, it provides an excellent opportunity to study the causal neuronal mechanisms of these two processes. In this review, we explore some of the possible causal neuronal mechanisms of associative learning of conditioned taste aversion (CTA) and its subsequent consolidation processes into LTM in L. stagnalis. In the CTA training procedure, a sucrose solution, which evokes a feeding response, is used as the conditioned stimulus (CS) and a potassium chloride solution, which causes a withdrawal response, is used as the unconditioned stimulus (US). The pairing of the CS–US alters both the feeding response of the snail and the function of a pair of higher order interneurons in the cerebral ganglia. Following the acquisition of CTA, the polysynaptic inhibitory synaptic input from the higher order interneurons onto the feeding CPG neurons is enhanced, resulting in suppression of the feeding response. These changes in synaptic efficacy are thought to constitute a “memory trace” for CTA in L. stagnalis.

Association of enhanced activity of indoleamine 2,3-dioxygenase in dendritic cells with the induction of regulatory T cells in chronic hepatitis C infection

BACKGROUND

Altered functions of dendritic cells (DCs) and/or increases of regulatory T cells (Tregs) are involved in the pathogenesis of chronic hepatitis C virus (HCV) infection. A tryptophan-catabolizing enzyme, indoleamine 2,3-dioxygenase (IDO), is reported to be an inducer of immune tolerance. Our aim was to clarify whether or not IDO is activated in chronic hepatitis C patients and its role in immune responses.

METHODS

This study enrolled 176 patients with chronic HCV infection and 37 healthy volunteers. Serum kynurenine concentration was evaluated by high-performance liquid chromatography, and its correlation with clinical parameters was examined. Monocyte-derived DCs were prepared from the subjects and subsequently stimulated with a combination of lipopolysaccharide and interferon-gamma to induce functional IDO (defined as IDO-DCs). The phenotypes, kynurenine or cytokine production, and T-cell responses with IDO-DCs were compared between the patients and healthy volunteers.

RESULTS

The serum kynurenine level in the patients was significantly higher than that in the healthy volunteers, and the level of serum kynurenine was positively correlated with the histological activity or fibrosis score. IDO activity in IDO-DCs from the patients was significantly higher than that in IDO-DCs from the volunteers. Furthermore, IDO-DCs from the patients induced more Tregs in vitro compared with those from the volunteers, and the frequency of induced Tregs by IDO-DCs was decreased with an IDO-specific inhibitor.

CONCLUSIONS

Systemic IDO activity is enhanced in chronic hepatitis C patients in correlation with the degree of liver inflammation and fibrosis. In response to inflammatory stimuli, DCs from the patients tend to induce Tregs, with some of this action being dependent on IDO.

TIE2-expressing monocytes as a diagnostic marker for hepatocellular carcinoma correlates with angiogenesis

Angiogenesis is a critical step in the development and progression of hepatocellular carcinoma (HCC). Myeloid lineage cells, such as macrophages and monocytes, have been reported to regulate angiogenesis in mouse tumor models. TIE2, a receptor of angiopoietins, conveys pro-angiogenic signals and identifies a monocyte/macrophage subset with pro-angiogenic activity. Here, we analyzed the occurrence and kinetics of TIE2-expressing monocytes/macrophages (TEMs) in HCC patients. This study enrolled 168 HCV-infected patients including 89 with HCC. We examined the frequency of TEMs, as defined as CD14+CD16+TIE2+ cells, in the peripheral blood and liver. The localization of TEMs in the liver was determined by immunofluorescence staining. Micro-vessel density in the liver was measured by counting CD34+ vascular structures. We found that the frequency of circulating TEMs was significantly higher in HCC than non-HCC patients, while being higher in the liver than in the blood. In patients who underwent local radio-ablation or resection of HCC, the frequency of TEMs dynamically changed in the blood in parallel with HCC recurrence. Most TEMs were identified in the perivascular areas of tumor tissue. A significant positive correlation was observed between micro-vessel density in HCC and frequency of TEMs in the blood or tumors, suggesting that TEMs are involved in HCC angiogenesis. Receiver operating characteristic analyses revealed the superiority of TEM frequency to AFP, PIVKA-II and ANG-2 serum levels as diagnostic marker for HCC.

CONCLUSION

TEMs increase in patients with HCC and their frequency changes with the therapeutic response or recurrence. We thus suggest that TEM frequency can be used as a diagnostic marker for HCC, potentially reflecting angiogenesis in the liver.

Different critical perinatal periods and hypothalamic sites of oestradiol action in the defeminisation of luteinising hormone surge and lordosis capacity in the rat

Female rats show a gonadotrophin-releasing hormone (GnRH)/luteinising hormone (LH) surge in the presence of a preovulatory level of oestrogen, whereas males do not because of brain defeminisation during the developmental period by perinatal oestrogen converted from androgen. The present study aimed to identify the site(s) of oestrogen action and the critical period for defeminising the mechanism regulating the GnRH/LH surge. Animals given perinatal treatments, such as steroidal manipulations, brain local implantation of oestradiol (E(2) ) or administration of an NMDA antagonist, were examined for their ability to show an E(2) -induced LH surge at adulthood. Lordosis behaviour was examined to compare the mechanisms defeminising the GnRH/LH surge and sexual behaviour. A single s.c. oestradiol-benzoate administration on either the day before birth (E21), the day of birth (D0) or day 5 (D5) postpartum completely abolished the E(2) -induced LH surge at adulthood in female rats, although the same treatment did not inhibit lordosis. Perinatal castration on E21 or D0 partially rescued the E2-induced LH surge in genetically male rats, whereas castration from E21 to D5 totally rescued lordosis. Neonatal E(2) implantation in the anterior hypothalamus including the anteroventral periventricular nucleus (AVPV)/preoptic area (POA) abolished the E(2) -induced LH surge in female rats, whereas E(2) implantation in the mid and posterior hypothalamic regions had no inhibitory effect on the LH surge. Lordosis was not affected by neonatal E(2) implantation in any hypothalamic regions. In male rats, neonatal NMDA antagonist treatment rescued lordosis but not the LH surge. Taken together, these results suggest that an anterior hypothalamic region such as the AVPV/POA region is a perinatal site of oestrogen action where the GnRH/LH regulating system is defeminised to abolish the oestrogen-induced surge. The mechanism for defeminisation of the GnRH/LH surge system might be different from that of sexual behaviour, in terms of the site(s) of oestrogen action and critical period, as well as the neurotransmitter system involved.

Simulation of citric acid production by rotating disk contactor

A simple model was presented to describe the time courses of citric acid production by a rotating disc contactor (RDC) using Aspergillus niger. The model is expressed by Monod-type cell growth, Luedeking-Piret-type citric acid production rate equations, and the diffusion equation for oxygen in the biofilm. The model contains five parameters which were determined by the nonlinear least squares method by fitting the numerical solution to the experimental data. In solving the equations, the cell density of the biofilm was estimated from the value of cellular mass per unit of biofilm area using an empirical equation. The experimental time courses in citric acid production period were well simulated with this model. The relation between the specific biofilm surface area and the rate of citric acid production was also explained by the simulation using the average values of five parameters of twelve runs. (c) 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 56: 689-696, 1997.

Insulin and memory in Lymnaea

The pond snail, Lymnaea stagnalis, is capable of learning conditioned taste aversion (CTA) and consolidating this CTA into long-term memory (LTM). The DNA microarray experiments showed that some of molluscan insulin-related peptides (MIPs) were up-regulated in snails exhibiting CTA-LTM. On the other hand, the electrophysiological experiments showed that application of secretions from the MIPs-containing cells evoked long-term potentiation (LTP) at the synapses between the cerebral giant cell (a key interneuron for CTA) and the B1 motoneuron (a buccal motoneuron). We thus hypothesized that MIPs and MIP receptors play an important role at the synapses, probably underlying the CTA-LTM consolidation process. To examine this hypothesis, we applied the antibody, which recognizes the binding site of mammalian insulin receptors and is thought to cross-react MIP receptors, to the Lymnaea CNS. Our present data showed that an application of the antibody for insulin receptors to the isolated CNS blocked LTP, and that an injection of the antibody into the Lymnaea abdominal cavity inhibited LTM consolidation, but not CTA formation.

Repetitive noxious stimulus altered the shadow-induced withdrawal behavior in Lymnaea

Stress alters adaptive behaviors including vigilance behaviors. In Lymnaea one of these vigilance behavior is a heightened withdrawal response to a shadow. The shadow withdrawal response (SWR) is mediated by dermal photoreceptors located primarily on the foot, mantle cavity, and skin around the pneumostome area. Here we asked whether we could obtain a neural correlate of the heightened SWR and other essential behaviors following traumatic stress. We measured the electrophysiological properties of 'Right Pedal Dorsal 11 (RPeD11)', the interneuron that plays a major role in mediating the whole-body withdrawal response. In traumatized snails 24 hours after the trauma they responded not only to a shadow stimulus with an augmented withdrawal response, but suppressed in locomotive, feeding and respiratory behavior. Their behavioral change lasted at least one week. Accompanying the behavioral change in these 'traumatized' preparations there are a number of significant changes in the neuronal properties of RPeD11 compared to naïve preparations. For example, RPeD11 is significantly more depolarized (∼10 mV) has significantly larger input resistance, and the duration of the response elicited by the shadow persists longer. All these changes result in an increased RPeD11 response and seem to raise their defensive alert level.

In vitro aversion conditioning in Lymnaea. Short communication

In an in vitro semi-intact Lymnaea preparation we were successful in using a training procedure to bring about Conditioning Taste Aversion (CTA ). Following paired presentation of the CS (sucrose) and US (tactile), the CS no longer elicits feeding. We can use sucrose to the lips in the semi-intact preparation as the CS; while we use direct current injection to depolarize RPeD11 as the US. Following pairing of these stimuli, the CS no longer elicits fictive feeding. We can determine the changes in synaptic input to neurons that play key roles in controlling feeding behavior.

Comparative analyses of regulatory T cell subsets in patients with hepatocellular carcinoma: a crucial role of CD25(-) FOXP3(-) T cells

Regulatory T cells (Tregs) play pivotal role in cancer-induced immunoediting. Increment of CD25(high+) FOXP3+ natural Tregs has been reported in patients with hepatocellular carcinoma (HCC); however, the involvement of other type of Tregs remain elusive. We aimed to clarify whether FOXP3- Tregs are increased and functionally suppressive or not in patients with HCC. We enrolled 184 hepatitis C-infected patients with chronic liver diseases or HCC, 57 healthy subjects and 27 HCC patients with other etiology. Distinct Treg subsets were phenotypically identified by the expression of CD4, CD25, CD127 and forkhead/winged helix transcription factor (FOXP3). Their gene profiles, frequency and suppressor functions against T cell proliferation were compared among the subjects. To examine the molecules involving in Treg differentiation, we cultured naive CD4+ T cells in the presence of HCC cells and dendritic cells. We determined two types of CD4+ CD127- T cells with comparable regulatory ability; one is CD25(high+) cells expressing FOXP3 (CD25(high+) FOXP3+ Tregs) and the other is CD25- cells without FOXP3- expression (CD25- FOXP3- cells). The peripheral or intrahepatic frequency of CD25- FOXP3- Tregs in HCC patients is higher than those in other groups, of which significance is more than CD25(high+) FOXP3+ cells. Of importance, CD25- FOXP3- Tregs, but not CD25(high+) FOXP3+ cells, dynamically change in patients accompanied by the ablation or the recurrence of HCC. CD25- FOXP3- T cells with CD127- IL-10+ phenoype are inducible in vitro from naive CD4(+) T cells, in which programmed cell death 1 ligand 1, immunoglobulin-like transcript 4 and human leukocyte antigen G are involved.. In conclusion, CD25- FOXP3- Tregs with suppressive capacity are increased in patients with HCC, suggesting their distinct roles from CD25+ FOXP3+ Tregs.

Dynamics of regulatory T cells and plasmacytoid dendritic cells as immune markers for virological response in pegylated interferon-α and ribavirin therapy for chronic hepatitis C patients

BACKGROUND

For the treatment of chronic hepatitis C, a combination of pegylated interferon-α (PEG-IFNα) and ribavirin has been widely used as a standard of care. Enhancement of immune response against hepatitis C virus (HCV) is known to be involved in the efficacy of the combination therapy. Our aim was to elucidate whether or not the frequency or function of blood cells is related to the outcome of the therapy.

METHODS

Sixty-seven chronic hepatitis C patients with high viral load of HCV genotype 1 infection who underwent 48 weeks of PEG-IFNα2b and ribavirin therapy were examined. During the treatment, frequencies of myeloid or plasmacytoid dendritic cells, Th1, Th2 cells, NK cells, and regulatory T cells were phenotypically determined.

RESULTS

Among the patients enrolled, 29 showed a sustained virological response (SVR), 18 a transient response (TR) and 17 no response (NR). The clinical and immunological markers were compared between the SVR and non-SVR patients, including TR and NR. Based on clinical, histological, immunological parameters, and cumulative dosage of PEG-IFNα2b and ribavirin, multivariate analyses revealed that higher platelet counts and higher regulatory T cell frequency at week 12 are indicative of SVR. Even in patients who attained complete early virological response at week 12, multivariate analyses disclosed that higher platelet counts and higher plasmacytoid dendritic cell frequency are indicative of SVR.

CONCLUSIONS

In PEG-IFNα and ribavirin combination therapy for chronic hepatitis C patients, the increments of regulatory T cells and plasmacytoid dendritic cell frequency are independently related to favorable virological response to the therapy.

Comprehensive immunological analyses of colorectal cancer patients in the phase I/II study of quickly matured dendritic cell vaccine pulsed with carcinoembryonic antigen peptide

Dendritic cell (DC) vaccine has been used to treat patients with advanced colorectal cancer (CRC). The results of vaccine-induced clinical responses have not always been satisfactory partially because of DC incompetence. In order to evaluate the feasibility of novel mature DCs for therapeutic adjuvants against CRC, we conducted clinical trials with carcinoembryonic antigen (CEA) peptide-loaded DC quickly generated with a combination of OK432 (Streptococcuspyogenes preparation), prostanoid, and interferon-α (OPA-DC). In the ten patients enrolled in this study, the OPA-DC vaccine was well tolerated and administered four times every 2 weeks except for two patients, who were switched to other treatments due to disease progression. Among the eight evaluable patients, one displayed stable disease (SD), while the remaining seven showed progressive disease (PD). In the SD patient, natural killer (NK) cell frequency and cytolytic activity were increased. In the same patient, the frequency of CEA-specific cytotoxic T cells (CTLs) increased stepwise with repetitive vaccinations; however, most of the CTLs exhibited central memory phenotype. In those with PD, NK cells proliferated well regardless of failure of response, whereas CTLs failed to do so. We concluded that the OPA-DC vaccine is well tolerated and has immune-stimulatory capacity in patients with CRC. Additional modulation is needed to attain significant clinical impact.

[Vaccine therapies against digestive-system cancers]

Cancer vaccine is a promising tool to achieve therapeutic responses in patients by inducing anti-tumor immunity. Several cancer vaccine trials have been performed in patients with digestive-system cancers. Two major candidates are peptide vaccine and dendritic cell (DC) vaccine. Since their clinical impacts are still limited, extensive studies are underway in order to identify more effective antigens or to potentiate DC functions. We developed a novel DC possessing potent stimulating activity for Th1, CTL, and NK cells, which are desirable for clinical DC vaccines. We performed the clinical trial using such DC for the treatment of colorectal cancer. In some of vaccinated patients, the capacity of NK cells and CTLs was successfully enhanced. Thus, cancer vaccines could be a therapeutic option for digestive-system cancers.

Multiple origins of outbreak populations of a native insect pest in an agro-ecosystem

Native insects can become epidemic pests in agro-ecosystems. A population genetics approach was applied to analyze the emergence and spread of outbreak populations of native insect species. Outbreaks of the mirid bug, Stenotus rubrovittatus, have rapidly expanded over Japan within the last two decades. To characterize the outbreak dynamics of this species, the genetic structure of local populations was assessed using polymorphisms of the mtDNA COI gene and six microsatellite loci. Results of the population genetic analysis suggested that S. rubrovittatus populations throughout Japan were genetically isolated by geographic distance and separated into three genetic clusters occupying spatially segregated regions. Phylogeographic analysis indicated that the genetic structure of S. rubrovittatus reflected post-glacial colonization. Early outbreaks of S. rubrovittatus in the 1980s occurred independently of genetically isolated populations. The genetic structure of the populations did not fit the pattern of an outbreak expansion, and therefore the data did not support the hypothesis that extensive outbreaks were caused by the dispersal of specific pestiferous populations. Rather, the historical genetic structure prior to the outbreaks was maintained throughout the increase in abundance of the mirid bug. Our study indicated that changes in the agro-environment induced multiple outbreaks of native pest populations. This implies that, given suitable environmental conditions, local populations may have the potential to outbreak even without invasion of populations from other environmentally degraded areas.

Enhanced ability of regulatory T cells in chronic hepatitis C patients with persistently normal alanine aminotransferase levels than those with active hepatitis

In hepatitis C virus (HCV) infection, the Th1-type immune response is involved in liver injury. A predominance of immunosuppressive regulatory T cells (Treg) is hypothesized in patients with persistently normal alanine aminotransferase (PNALT). Our aim was to clarify the role of Treg in the pathogenesis of PNALT. Fifteen chronically HCV-infected patients with PNALT, 21 with elevated ALT (CH) and 19 healthy subjects (HS) were enrolled. We determined naturally-occurring Treg (N-Treg) as CD4+CD25high+FOXP3+ T cells. The expression of FOXP3 and CTLA4 in CD4+CD25high+ cells was quantified by real-time reverse transcriptase-polymerase chain reaction. Bulk or CD25-depleted CD4+ T cells cultured with HCV-NS5 loaded dendritic cells were assayed for their proliferation and cytokine release. We examined CD127-CD25-FOXP3+ cells as distinct subsets other than CD25+ N-Treg. The frequencies of N-Treg in patients were significantly higher than those in HS. The FOXP3 and CTLA4 transcripts were higher in PNALT than those in CH. The depletion of CD25+ cells enhanced HCV-specific T cell responses, showing that co-existing CD25+ cells are suppressive. Such inhibitory capacity was more potent in PNALT. The frequency of CD4+CD127-CD25-FOXP3+ cells was higher in CH than those in PNALT. Treg are more abundant in HCV-infected patients, and their suppressor ability is more potent in patients with PNALT than in those with active hepatitis.

Neurophysiological analysis of visuo-vestibular conditioning in Lymnaea stagnalis

Lymnaea are capable of learning an association between light and rotation. The conditioning paradigm to produce this association and the unconditioned escape response are the same for both Lymnaea and Hermissenda, but the underlying neural mechanisms appear to differ between the two species due to differences in the organization and function of their visuo- and vestibular-sensory systems. The RPeD11 interneuron in Lymnaea controls withdrawal behavior. We analyzed the electrophysiologic characteristics of the RPeD11 and observed an increase in cell excitability; that is, spontaneous activity of the postsynaptic potential in the RpeD11 was increased in conditioned animals after learning acquisition.

Relationship between developmental synaptic modulation and conditioning-induced synaptic change in Lymnaea

Though adult Lymnaea are bimodal breathers, young animals breathe mainly through the skin and adults through the lung. Operant conditioning changes adult breathing behavior from aerial to cutaneous. We hypothesized that this behavioral change is caused by alterations in the neuronal circuit during both development and conditioning. We focused our study on whether the synaptic connection between RPeD1 and RPA6 neurons is modulated during development and conditioning. Our findings indicated that the RPeD1 has an excitatory monosynaptic contact with the RPA6 in young naive and operantly-conditioned adult animals. The relationship of this contact was well correlated with their respiratory behavior.

Impaired cytokine response in myeloid dendritic cells in chronic hepatitis C virus infection regardless of enhanced expression of Toll-like receptors and retinoic acid inducible gene-I

Dendritic cells utilize various sets of Toll-like receptors (TLR) or cytosolic sensors to detect pathogens and evoke immune responses. In patients with hepatitis C virus (HCV) infection, a higher prevalence of various infectious diseases is reported; suggesting that innate immunity against pathogens is impaired. The aim of this study was to clarify whether the TLR and retinoic acid inducible gene-I (RIG-I) system in myeloid dendritic cells is preserved or not in chronic HCV infection. The expression of TLRs, RIG-I and its relatives were compared in myeloid dendritic cells between 39 patients and 52 healthy volunteers. The induction of type-I interferon (IFN) and inflammatory cytokines was examined in response to agonists for TLR2 (palmitoyl-3-cysteine-serine-lysine-4), TLR3/RIG-I (polyinosine-polycytidylic acid) or TLR4 (lipopolysaccharide). The relative expressions of TLR2, TLR4, RIG-I, and LGP2 from the patients were significantly higher than those from the volunteers, whereas TLR3 and MDA-5 expressions did not differ. In search for factors regulating TLR/RIG-I expression, it was shown that IFN-alpha, polyinosine-polycytidylic acid and lipopolysaccharide induced TLR3, TLR4 and RIG-I, but TNF-alpha, HCV core or HCV non-structural proteins did not. For the functional analyses, myeloid dendritic cells from the patients induced significantly less amounts of IFN-beta, TNF-alpha and IL-12p70 in response to polyinosine-polycytidylic acid or lipopolysaccharide. It is noteworthy that the expression of TRIF and TRAF6, which are essential adaptor molecules transmitting TLR3 or TLR4-dependent signals, is reduced in the patients. Thus, innate cytokine responses in myeloid dendritic cells are impaired regardless of enhanced expressions of TLR2, TLR4, and RIG-I in HCV infection.

Immunohistological studies on the distribution of learning-related peptides in the central nervous system of conditioned Lymnaea

Behavioral conditioning in Lymnaea increased the amount of immunolabeling in the central nervous system for the memory-associated protein calexcitin. The staining level of anti-calexcitin positive neurons was always stronger in conditioned animals than in naive animals. In the visuo-vestibular conditioned animals, right-parietal and visceral group neurons as well as withdrawal-related neurons were positively stained with anti-calexcitin antibody. In taste-aversion conditioned animals, right-parietal visceral G-group neurons and withdrawal-related neurons were selectively stained. These neurons are candidate neurons for modulation by these conditioning paradigms.

Oestrogen-dependent stimulation of luteinising hormone release by galanin-like peptide in female rats

Galanin-like peptide (GALP), a ligand for three types of galanin receptor, is reported to have a role in regulating luteinising hormone (LH) release in male rodents and primates, but its role in LH release in female rodents remains controversial. The present study was conducted to test whether GALP has a stimulatory role in regulating LH secretion in female rats. The effect of i.c.v. infusion of GALP (5 nmol) on pulsatile LH release was investigated in Wistar-Imamichi strain female rats, or lean and obese Zucker rats. In oestradiol-17beta (oestradiol)-primed ovariectomised (OVX) Wistar-Imamichi female rats, i.c.v. infusion of GALP caused a gradual increase in LH release for the first 1.5 h after the infusion followed by an increased LH pulse frequency during the next 1.5 h, resulting in a significant increase in the mean LH concentrations and baseline levels of LH pulses throughout the sampling period and in the frequency of LH pulses at the last half of the period compared to vehicle-treated controls. The stimulatory effect of GALP was oestrogen-dependent because the same GALP treatment did not affect LH release in OVX rats in the absence of oestradiol. In lean Zucker rats, LH pulses were found in oestradiol-primed OVX individuals and central GALP infusion increased mean LH concentrations in the last half of the period. By contrast, few LH pulses were found in oestradiol-primed OVX obese Zucker rats reportedly with lower hypothalamic GALP expression. Central GALP infusion caused an apparent but transient increase in LH release, resulting in the significant increase in all pulse parameters of LH pulses compared to vehicle-treated controls in the first half of the sampling period. These results suggest that hypothalamic GALP is likely involved in stimulating GnRH/LH release, and that the stimulatory effect of GALP on LH release is oestrogen-dependent in female rats.

Involvement of dendritic cell frequency and function in virological relapse in pegylated interferon-alpha and ribavirin therapy for chronic hepatitis C patients

A combination of pegylated interferon alpha (PEG-IFNalpha) and ribavirin has been used widely. Enhancement of immune response against hepatitis C virus (HCV) is known to be involved in the efficacy of the combination therapy. The aim of the study was to elucidate whether the frequency or function of immunocompetent blood cells is related to the outcome of the therapy. Twenty-five chronic hepatitis C patients with high viral load of HCV genotype 1 who underwent 48 weeks of PEG-IFNalpha2b and ribavirin therapy were examined. During the treatment, frequencies of dendritic cell subsets, helper T cell subsets, and NK cells were phenotypically determined. In some patients, the ability of dendritic cells to stimulate allogeneic CD4(+)T cells was examined at the end and after the therapy. Among the 25 patients, 11 showed a sustained virological response, 11 a transient response, and 3 no response. In comparison with sustained virological responders, non-sustained virological responders showed impaired dendritic cell function at the end and after the treatment. The transient responders showed a decline of plasmacytoid dendritic cell frequency from Weeks 1-12 and impaired dendritic cell function as well. Even in patients who attained negative serum HCV RNA at Week 12, the transient responders showed a significant decrease of plasmacytoid dendritic cell frequency and impaired dendritic cell function. In conclusion, in PEG-IFNalpha and ribavirin combination therapy for chronic hepatitis C patients, the early-phase plasmacytoid dendritic cell frequency and/or end-of-treatment dendritic cell function are related to the virological outcome of the therapy.

Pathologic complete remission of cytologically proven axillary node metastases may be a strong prognostic factor in HER2-positive breast cancer

21149

Background: Preoperative chemotherapy has become one of the standard modes of treatment in patients with breast cancer, and pathologic complete remission (pCR) thus obtained has become an important prognostic factor. However, the number of cells in the main lesion is enormous and changes over time in a heterogeneous manner. Thus, time and individual differences in sensitivity influence the acquisition of pCR, and questions about the coincidence with the effects of metastatic lesions also remain. On the other hand, although pCR of axillary lymph node metastasis lesions with relatively lower numbers of the cells is considered one of the best surrogate prognostic markers, evaluation criteria have not yet been established because definitive preoperative diagnosis is difficult. In our department, preoperative axillary cytodiagnosis has been conducted in all surgical breast cancer cases. In this study, we investigated pCR of the axillary lymph nodes (ALN- pCR) in cytologically proven axillary node metastasis cases. Subjects and Methods: ALN-pCR, DFS, and OS were investigated in 52 surgical breast cancer cases (observation period: 15–52 months; medial level: 28 months) positive for cytological axillary metastasis and received preoperative chemotherapy (AC-Paclitaxel) during the period from 2002 to 2005. Results: ALN-pCR was found in 21 of 52 cases (40.4%). Rates of disease-free survival (DFS) at 36 months in ALN-pCR and non-ALN-pCR cases were 85.0% and 42.3% (P=0.031) and those of overall survival (OS; 48 months) were 100% and 87.9% (P=0.353), respectively. DFS (36 months) was very favorable 100% in ALN-pCR cases that obtained the effect of 1b or higher on evaluation of the main lesion effect and ALN-pCR cases with Her2-positive results on sub-type analysis. Conclusions: ALN-pCR of cytologically proven axillary node metastasis was indicated to be a prognostic factor in cases of breast cancer. Especially, its importance was demonstrated in HER2-positive breast cancer. From these findings, HER2-positive and cytologically axillary lymph node-positive cases were considered the best indications for preoperative chemotherapy.

No significant financial relationships to disclose.

Use of oblique supine magnetic resonance imaging in breast-conserving surgery following neoadjuvant chemotherapy

11064

Background: The success of breast-conserving surgery (BCS) after neoadjuvant chemotherapy (NAC) is dependent on accurate assessment of the extent of surgical excision of the original tumor bed (OTB). However the difficulty in locating microscopic residual disease often leads to a high re-excision rate (RER) and large excision specimen area (ESA). Methods: Magnetic resonance imaging (MRI) scans in the oblique supine position are performed with the patient in the same posture as that adopted during surgery. Maximum intensity projection (MIP) images of MR coronary section images of OTB are generated and used for surgery. OTB images are copied onto transparent sheets overlaid on the MIP images. These images are projected onto the breast before surgery, and used to determine the lines for surgical excision. In the conventional method (CM), OTB is determined by ultrasonography (US) and CT images. The oblique supine MRI method (SMM) has been used at our hospital since 2005. In this study, 14 patients treated prospectively with SMM (12/05- 12/06) were compared with a series of 19 consecutive patients treated with CM (04/03–11/05). ESA and RER were analyzed. Re-excision was performed in cases with a calcified lesion or tumor within 1 cm of the excised margin by X-ray or US during surgery, or invasive cancer was detected within 1 mm by pathological examination. ESA was analyzed using NIH Image. All patients received anthracycline/taxane-based chemotherapy. Results: There were no significant differences in characteristics of patients in the initial stages (T1, 2) or pathological chemotherapy responses between SMM and CM groups. There were four T3.4 cases in the SMM group, but none in the CM group. Clinical responses in CM and SMM were as follows (cases): CR 6, 7; PR 12, 7; SD 1, 0, respectively. RER was significantly greater in CM (36.8%, n=7) than in SMM (7.1%, n=1) (P<0.05). Average ESA in SMM were 19.0 cm2 (n=2) in T1, 33.6 cm2 (7) in T2, and 59.3 cm2 (5) in T3.4, while corresponding values in CM were 49.4 cm2 (4) and 65.5 cm2 (15), respectively; ESA was significantly improved in SMM. Conclusions: SMM, which has the benefits of decreased ESA and RER with superior cosmetic results, is a reliable technique for BCS following NAC.

No significant financial relationships to disclose.

Impaired ability of interferon-alpha-primed dendritic cells to stimulate Th1-type CD4 T-cell response in chronic hepatitis C virus infection

In interferon-alpha (IFN-alpha)/ribavirin combination therapy for chronic hepatitis C (CHC), an enhanced T helper 1 (Th1) response is essential for the eradication of hepatitis C virus (HCV). We aimed to elucidate the role of IFN-alpha or IFN-alpha/ribavirin in dendritic cell (DC) ability to induce Th1 response in HCV infection. We generated monocyte-derived DC from 20 CHC patients and 15 normal subjects driven by granulocyte-macrophage colony-stimulating factor and interleukin 4 (IL-4) without IFN-alpha (GM/4-DC), with IFN-alpha (IFN-DC), with ribavirin (R-DC) or with IFN-alpha/ribavirin (IFN/R-DC) and compared their phenotypes and functions between the groups. We also compared them in 14 CHC patients between who subsequently attained sustained virological response (SVR) and who did not (non-SVR) by 24 weeks of IFN-alpha/ribavirin therapy. Compared with GM/4-DC, IFN-DC displayed higher CD86 expression, but lesser ability to secrete IL-10 and were more potent to prime CD4(+) T cells to secrete IFN-gamma and IL-2. Such differences were more significant in healthy subjects than in CHC patients. No additive effect of ribavirin was observed in DC phenotypes and functions in vitro either which was used alone or in combined with IFN-alpha. However, in the SVR patients, an ability of IFN/R-DC to prime T cells to secrete IFN-gamma and IL-2 was higher than those of IFN-DC and those of IFN/R-DC in the non-SVR group, respectively. In conclusion, DC from CHC patients are impaired in the ability to drive Th1 in response to IFN-alpha. Such DC impairment is restored in vitro by the addition of ribavirin in not all but some patients who cleared HCV by the combination therapy.

Purification, characterization, and potential applications of formate oxidase from Debaryomyces vanrijiae MH201

Formate oxidase was found in cell-free extracts of Debaryomyces vanrijiae MH201, a soil isolate. After purification by column chromatography, the preparation showed a protein band corresponding to a molecular mass (MM) of 64 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The MM, estimated by a gel filtration, was 99 kDa. The preparation showed two and three bands on isoelectric focusing under denaturing and native conditions, respectively. These results suggest that the preparation contained three isoforms, each of which might be composed of alphaalpha, alphabeta, and betabeta subunits with apparently similar MM. The preparation acted on formate with K (m) and V (max) values of 11.7 mM and 262 micromol min(-1) mg(-1), respectively, at pH 4.5 and 25 degrees C, but showed no evidence of activity on the other compounds tested. The optimum pH and temperature were pH 4.0 and 35 degrees C, respectively. The preparation showed activities of 85% of the initial activity after storage at pH 6.0 and 4 degrees C for 8 weeks. When 10 mM formaldehyde was reacted with 2.0 U ml(-1) of the enzyme preparation at pH 5.5 and room temperature in the presence of 2.0 U ml(-1) of a microbial aldehyde oxidase and 100 U ml(-1) of catalase for 180 min, neither of formate nor formaldehyde was detected, suggesting that the reaction involved the quantitative conversion of formaldehyde to carbon dioxide.

Enhanced ability of peripheral invariant natural killer T cells to produce IL-13 in chronic hepatitis C virus infection

BACKGROUND/AIMS

Human invariant natural killer T (iNKT) cells express a TCR Valpha24-JalphaQ paired with Vbeta11 and are activated by a surrogate ligand, alpha-galactosylceramide (alphaGalCer). The iNKT cells are involved in the regulation of anti-viral immune responses; however, little is known about their roles in hepatitis C virus (HCV) infection.

METHODS

We compared the frequency of peripheral iNKT cells and their cytokine producing capacity reactive to alphaGalCer between chronically HCV-infected patients and healthy subjects. Cytokine production of freshly isolated iNKT cells were analyzed by ELISPOT. Activated iNKT cells were obtained by culture with alphaGalCer-loaded dendritic cells (DCs) and re-stimulated with them for the measurement of cytokine production.

RESULTS

The frequencies of iNKT cells were not different between HCV-infected patients and healthy subjects. The number of fresh IFN-gamma-producing iNKT cells reactive to alphaGalCer was not different between the patients and controls, whereas fresh iNKT cells produced negligible amounts of Th2 cytokines regardless of HCV infection. In response to alphaGalCer, expanded iNKT cells from the patients secreted IFN-gamma comparable in amount to controls, whereas they released significantly more IL-13 than cells from controls.

CONCLUSIONS

Activated iNKT cells from HCV-infected patients gain more ability to secrete IL-13 than those from healthy subjects.