A Prospective Study Exploring the Safety and Efficacy of Lenvatinib for Patients with Advanced Hepatocellular Carcinoma and High Tumor Burden: The LAUNCH Study

PURPOSE

This study aimed to investigate the safety and efficacy of lenvatinib in real-world settings, including patients excluded from the REFLECT trial, a phase III trial that compared lenvatinib with sorafenib.

PATIENTS AND METHODS

This multicenter, nonrandomized, open-label prospective study was conducted at 10 medical facilities in Japan (jRCTs031190017). Eligible patients had advanced hepatocellular carcinoma (HCC) and were suitable for lenvatinib therapy. The study included patients with high tumor burden (with >50% intrahepatic tumor volume, main portal vein invasion, or bile duct invasion), Child-Pugh B status, and receiving lenvatinib as second-line therapy following atezolizumab plus bevacizumab.

RESULTS

From December 2019 to September 2021, 59 patients were analyzed (47 and 12 patients with Child-Pugh A and B, respectively). In patients with Child-Pugh A, the frequency of aspartate aminotransferase elevation was high (72.7%) in the high-burden group. No other significant ad verse events (AE) were observed even in second-line treatment. However, patients with Child-Pugh B had high incidence of grade ≥3 AE (100.0%) and high discontinuation rates caused by AE (33.3%) compared with patients with Child-Pugh A (80.9% and 17.0%, respectively). Median progression-free survival was 6.4 and 2.5 months and median overall survival was 19.7 and 4.1 months in Child-Pugh A and B, respectively. Lenvatinib plasma concentration was higher in patients with Child-Pugh B on days 8 and 15 and correlated with dose modifications and lower relative dose intensity.

CONCLUSIONS

Lenvatinib is safe and effective for advanced HCC in patients with Child-Pugh A, even with high tumor burden. However, it carries a higher risk of AE and may not provide adequate efficacy for patients with Child-Pugh B status.

Hyperprogressive disease during atezolizumab plus bevacizumab treatment in patients with advanced hepatocellular carcinoma from Japanese real-world practice

BACKGROUND

Hyperprogressive disease (HPD) is a phenomenon with greatly accelerated tumor growth and clinical deterioration rates compared to pre-therapy, in patients treated with immune checkpoint inhibitors (ICI). The aim of this study is to clarify the reality of HPD in patients with advanced hepatocellular carcinoma (HCC) who were treated with atezolizumab plus bevacizumab (Atez/Bev) using tumor dynamics.

METHODS

Medical records of consecutive patients with advanced HCC who were treated with Atez/Bev were retrospectively reviewed. HPD was defined as a more than two- or fourfold increase in tumor growth rate (TGR) or tumor growth kinetics rate (TGK_R) before and after treatment. Overall survival (OS) and baseline characteristics with or without HPD were analyzed.

RESULTS

A total of 85 patients were included in the analysis. When HPD was defined as a twofold of TGR or TGK_R, 8 patients (8/85, 9.4%) had HPD and 11 had PD without HPD. A total of 5 patients (5/85, 5.9%) were diagnosed with HPD and 14 with PD without HPD when HPD was defined as a fourfold of TGR or TGK_R. No significant difference was observed in the baseline characteristics between HPD and non-HPD.

CONCLUSION

The prevalence of HPD in patients with advanced HCC treated with Atez/Bev was lower than those treated with nivolumab monotherapy. The HPD mechanism in ICI combined with antibodies targeting vascular endothelial growth factor (VEGF) remains to be elucidated.

Use of ramucirumab for various treatment lines in real-world practice of patients with advanced hepatocellular carcinoma

PURPOSE

Ramucirumab was shown to be effective as a second-line treatment after sorafenib in patients with advanced hepatocellular carcinoma (HCC) with alpha-fetoprotein levels > 400 ng/mL in a worldwide phase 3 trial. Ramucirumab is used in patients pretreated with various systemic therapies in clinical practice. We retrospectively examined the treatment outcomes of ramucirumab administered to advanced HCC patients after diverse systemic therapies.

METHODS

Data were collected from patients with advanced HCC who received ramucirumab at three institutions in Japan. Radiological assessments were determined according to both Response Evaluation Criteria in Solid Tumours (RECIST) version 1.1 and modified RECIST and the Common Terminology Criteria for Adverse Events version 5.0 was used to assess adverse events.

RESULTS

A total of 37 patients treated with ramucirumab between June 2019 and March 2021 were included in the study. Ramucirumab was administered as second, third, fourth, and fifth-line treatment in 13 (35.1%), 14 (37.8%), eight (21.6%), and two (5.4%) patients, respectively. Most patients (29.7%) who received ramucirumab as a second-line therapy were pretreated with lenvatinib. We found grade 3 or higher adverse events only in seven patients and no significant changes in the albumin-bilirubin score during ramucirumab treatment in the present cohort. The median progression-free survival of patients treated with ramucirumab was 2.7 months (95% confidence interval, 1.6-7.3).

CONCLUSION

Although ramucirumab is used for various lines of treatment other than second-line immediately after sorafenib, its safety and effectiveness were not significantly different from the findings of the REACH-2 trial.

Clinical effects and emerging issues of atezolizumab plus bevacizumab in patients with advanced hepatocellular carcinoma from Japanese real-world practice

BACKGROUND

Although the efficacy of atezolizumab has been demonstrated in randomized controlled trials, its long-term efficacy and association with adverse events in real-world practice are unknown. This study was designed to shed light on these issues.

METHODS

In this multicenter retrospective study, data were collected from patients with advanced hepatocellular carcinoma treated with atezolizumab plus bevacizumab in seven institutions in Japan. The authors focused on the efficacy and adverse events related to vascular endothelial growth factor (VEGF) inhibition.

RESULTS

A total of 123 patients were enrolled in this study. The median progression-free survival (PFS) for the first-line treatment group was 8.0 months (95% confidence interval [CI], 6.1-9.9), whereas the median PFS for the second- or later-line treatment group was 4.1 months (95% CI, 2.6-5.7), which was significantly worse than that of the first-line treatment group (p = .005). Twenty-seven patients had interrupted bevacizumab treatment. Proteinuria accounted for the largest proportion of bevacizumab treatment interruptions. The cumulative incidence rate of bevacizumab interruption due to anti-VEGF-related adverse events was significantly higher in patients with hypertension and/or diabetes mellitus than in those without (p = .026). The landmark analysis showed that patients experienced bevacizumab interruption by 24 weeks from treatment initiation had poorer PFS than those who did not (p = .013).

CONCLUSIONS

The PFS of atezolizumab plus bevacizumab as first-line treatment mostly replicates that of a global phase 3 trial. Interrupted bevacizumab treatment was more common in patients with hypertension and/or diabetes mellitus, which may be associated with worsening long-term PFS.

PLAIN LANGUAGE SUMMARY

Atezolizumab plus bevacizumab has been the standard front line systemic therapy for advanced hepatocellular carcinoma. With the growing incidence of fatty liver due to metabolic syndrome as a background liver disease for hepatocellular carcinoma, the rate of comorbid hypertension and diabetes mellitus has been increasing accordingly. The present study demonstrated the cumulative incidence rate of bevacizumab interruption due to anti-VEGF-related adverse events was significantly higher in patients with hypertension and/or diabetes mellitus. The landmark analysis clarified that interruption of bevacizumab might be a risk of impaired efficacy of atezolizumab plus bevacizumab over the long term in patients with advanced hepatocellular carcinoma.

A prospective study exploring the safety and efficacy of lenvatinib for patients with advanced hepatocellular carcinoma potential in current real-world practice

512

Background: Lenvatinib has been widely used as a leading oral multikinase inhibitor for advanced hepatocellular carcinoma (HCC) patients in real-world practice worldwide. However, in the global phase 3 study comparing the effectiveness of lenvatinib and sorafenib, only a limited population of patients were enrolled, excluding those who had a high-burden intrahepatic lesion or Child-Pugh class (C-P) B, who were likely to receive systemic therapy in the clinical practice. Currently, combination immunotherapy has replaced multikinase inhibitors as the standard first-line treatment. Therefore, this prospective study explored the safety and efficacy of lenvatinib in the patient population, which would be used in real-world practice. Methods: This was an open-label, multicenter, prospective study that enrolled patients who had advanced HCC with C-P A or B, treated with lenvatinib as first-line or second-line after atezolizumab plus bevacizumab (Atz + Bv) at 10 sites in Japan. The study included patients who had high tumor burden, defined as identifying either tumor volume of more than 50% of the liver, portal vein tumor thrombosis reaching the main trunk or the contralateral branch, or bile duct invasion at baseline (jRCTs031190017). Results: Between December 1, 2019, and September 30, 2021, 59 patients were recruited for this study. At the time of enrollment, 47 and 12 patients were classified as C-P A and B, respectively. This study included 11 patients with high tumor burden and 12 treated with second-line after Atz + Bv. All patients with high tumor burden and second-line treatment were classified as C-P A. Median overall survival of C-P A and B patients was 20.3 and 4.2 months, respectively. Similarly, progression-free survival according to modified RECIST (mRECIST) of C-P A and B patients was 4.8 and 2.8 months, respectively. Objective response rate (ORR) according to mRECIST in C-P A patients was 61.9%, whereas in C-P B patients was 25.0%. ORRs of high-burden group and second-line group were 80.0% and 40.0%, respectively. Major severe adverse events (AE) (≥grade 3) in C-P A patients were hypertension (41.3%) and proteinuria (23.9%). In contrast, those in C-P B patients were hyponatremia (41.7%), elevated aspartate aminotransferase (41.7%), hypertension (33.3%), decreased appetite (16.7%), diarrhea (16.7%), and proteinuria (16.7%). Discontinuation rate due to AE of C-P A and B patients was 17.4% and 33.3%, respectively. In high-burden and second-line groups, 10% and 20% discontinued lenvatinib due to AE, respectively. Conclusions: Lenvatinib is expected to be safe and effective in patients with advanced HCC who have a high tumor burden and second-line treatment after Atz + Bv, whereas liver function was maintained with C-P A. However, in C-P B, this study found lower efficacy and higher discontinuation rates due to AE compared with C-P A. Clinical trial information: s031190017 .

Carbon-ion radiotherapy versus radiofrequency ablation as initial treatment for early-stage hepatocellular carcinoma

AIM

Carbon-ion radiotherapy (C-ion RT) has shown potential as a curative treatment for patients with hepatocellular carcinoma (HCC). However, no reports have compared the effectiveness of C-ion RT and radiofrequency ablation (RFA). This study aimed to compare clinical outcomes between C-ion RT and RFA for patients with early-stage HCC.

METHODS

Medical records of consecutive patients with HCC (single lesion ≤5 cm or two to three lesions ≤3 cm) who received either C-ion RT or RFA as initial treatment were retrospectively reviewed. Propensity score matching (PSM) was used to adjust for clinical factors between both groups.

RESULTS

A total of 560 patients were included, among whom 69 and 491 received C-ion RT and RFA, respectively. After PSM (C-ion RT, 54 patients; RFA, 95 patients), both groups were well balanced. Carbon-ion radiotherapy had significantly lower cumulative intrasubsegmental recurrence rate after PSM compared to RFA (p = 0.004) (2-year, 12.6% vs. 31.7%; 5-year, 15.5% vs. 49.6%, respectively). However, no significant difference in cumulative local recurrence rate, stage progression-free survival, or overall survival (OS) was observed between both groups. In the RFA group, 6 of 491 patients (1.2%) showed grade 3 adverse events, whereas no grade 3 or higher adverse events were observed in the C-ion RT group.

CONCLUSION

Carbon-ion radiotherapy provided a lower cumulative intrasubsegmental recurrence rate, but a comparable cumulative local recurrence rate, stage progression-free survival, and OS compared to RFA. Thus, C-ion RT appears to be one of the effective treatment options for early-stage HCC when RFA is deemed not indicated.

Posttreatment after Lenvatinib in Patients with Advanced Hepatocellular Carcinoma

BACKGROUND

There is no standard posttreatment for patients with advanced hepatocellular carcinoma (HCC) in whom lenvatinib therapy has failed. This study aimed to investigate rates of migration to posttreatment after lenvatinib and to explore candidates for second-line agents in the patients with failed lenvatinib therapy.

METHODS

We retrospectively collected data on patients with advanced HCC who received lenvatinib as the first-line agent in 7 institutions.

RESULTS

Overall survival and progression-free survival (PFS) of 178 patients who received lenvatinib as the first-line agent were 13.3 months (95% confidence interval [CI], 11.5-15.2) and 6.7 months (95% CI, 5.6-7.8), respectively. Sixty-nine of 151 patients (45.7%) who discontinued lenvatinib moved on to posttreatment. The migration rates from lenvatinib to the second-line agent and from the second-line agent to the third-line agent were 41.7 and 44.4%, respectively. Based on multivariate analysis, response to lenvatinib (complete or partial response according to modified RECIST) and discontinuation of lenvatinib due to radiological progression, as well as male were associated with a significantly higher probability of migration to posttreatment after lenvatinib. On the other hand, alpha-fetoprotein levels of 400 ng/mL or higher was correlated with a significantly lower probability of migration to posttreatment after lenvatinib. Of 63 patients who received second-line systemic therapy, 53 (84.2%) were administered sorafenib. PFS, objective response rate (ORR), and disease control rate (DCR) for sorafenib treatment were 1.8 months (95% CI, 0.6-3.0), 1.8%, and 20.8%, respectively. According to the Cox regression hazard model, Child-Pugh class B significantly contributed to shorter PFS. PFS, ORR, and DCR of 22 patients who received regorafenib after lenvatinib in any lines were 3.2 months (range, 1.5-4.9 months), 13.6%, and 36.3%, respectively. Similarly, PFS, ORR, and DCR of 17 patients who received regorafenib after lenvatinib in the third-line (after sorafenib) were 3.8 months (range, 1.1-6.5 months), 17.6%, and 41.2%, respectively.

CONCLUSION

Sorafenib may not be a candidate for use as a posttreatment agent after lenvatinib, according to the results of the present study. Regorafenib has the potential to become an appropriate posttreatment agent after lenvatinib.

The impact of FGF19/FGFR4 signaling inhibition in antitumor activity of multi-kinase inhibitors in hepatocellular carcinoma

FGF19/FGFR4 autocrine signaling is one of the main targets for multi-kinase inhibitors (MKIs). However, the molecular mechanisms underlying FGF19/FGFR4 signaling in the antitumor effects to MKIs in hepatocellular carcinoma (HCC) remain unclear. In this study, the impact of FGFR4/ERK signaling inhibition on HCC following MKI treatment was analyzed in vitro and in vivo assays. Serum FGF19 in HCC patients treated using MKIs, such as sorafenib (n = 173) and lenvatinib (n = 40), was measured by enzyme-linked immunosorbent assay. Lenvatinib strongly inhibited the phosphorylation of FRS2 and ERK, the downstream signaling molecules of FGFR4, compared with sorafenib and regorafenib. Additional use of a selective FGFR4 inhibitor with sorafenib further suppressed FGFR4/ERK signaling and synergistically inhibited HCC cell growth in culture and xenograft subcutaneous tumors. Although serum FGF19^high (n = 68) patients treated using sorafenib exhibited a significantly shorter progression-free survival and overall survival than FGF19^low (n = 105) patients, there were no significant differences between FGF19^high (n = 21) and FGF19^low (n = 19) patients treated using lenvatinib. In conclusion, robust inhibition of FGF19/FGFR4 is of importance for the exertion of antitumor effects of MKIs. Serum FGF19 levels may function as a predictive marker for drug response and survival in HCC patients treated using sorafenib.

Propofol versus midazolam for sedation during radiofrequency ablation in patients with hepatocellular carcinoma

Background and Aim

Standardization of the sedation protocol during radiofrequency ablation (RFA) in patients with hepatocellular carcinoma (HCC) is needed. This randomized, single‐blind, investigator‐initiated trial compared clinical outcomes during and after RFA using propofol and midazolam, respectively, in patients with HCC.

Methods

Few‐ and small‐nodule HCC patients (≤3 nodules and ≤3 cm) were randomly assigned to either propofol or midazolam. Patient satisfaction was assessed using a 100‐mm visual analog scale (VAS) (1 mm = not at all satisfied, 100 mm = completely satisfied). Sedation recovery rates 1, 2, 3, and 4 h after RFA were evaluated based on Modified Observer's Assessment of Alertness/Sedation (MOAA/S) scores; full recovery was defined as a MOAA/S score of 5.

Results

Between July 2013 and September 2017, 143 patients with HCC were enrolled, and 135 patients were randomly assigned to the treatment group. Compared with midazolam, propofol exhibited similar median procedural satisfaction (propofol: 73.1 mm, midazolam: 76.9 mm, P = 0.574). Recovery rates 1 and 2 h after RFA were higher in the propofol group than in the midazolam group. Meanwhile, recovery rates observed 3 and 4 h after RFA were similar in the two groups. The safety profiles during and after RFA were almost identical in the two groups.

Conclusion

Patient satisfaction was almost identical in patients receiving propofol and midazolam sedation during RFA. Propofol sedation resulted in reduced recovery time compared with midazolam sedation in patients with HCC. The safety profiles of both propofol and midazolam sedation during and after RFA were acceptable.

Posttreatment after lenvatinib in patients with advanced hepatocellular carcinoma

278

Background: In clinical practice, the major disadvantage of lenvatinib to treat advanced hepatocellular carcinoma (HCC) is the lack of a posttreatment agent that has shown clear effectiveness. Thus, the establishment of second-line treatment after lenvatinib treatment failure is an urgent clinical issue to be addressed in systemic therapy in patients with advanced HCC. The study used real-world clinical data to explore candidate drugs that might be appropriate as second-line treatment after lenvatinib. Methods: We retrospectively reviewed the medical records of all patients with advanced HCC who received lenvatinib as the first-line agent in seven institutions in Japan between 23 March 2018 and 31 September 2019. Results: During the study period, 178 patients with advanced HCC received lenvatinib as first-line systemic therapy. At the time of lenvatinib administration, most patients were Eastern Cooperative Oncology Group Performance Status grade 0 or 1 (94.9%) and Child–Pugh class A (84.3%). According to the baseline radiological assessments, 25.3% and 36.0% of patients had macrovascular invasion and extrahepatic metastasis, respectively. Overall survival and progression-free survival (PFS) for lenvatinib treatment were 13.3 months (95% CI: 11.5–15.2) and 6.7 months (95% CI: 5.1–8.3), respectively. Of the 151 patients who discontinued lenvatinib, 71 (47.0%) converted to posttreatment. The conversion rates from lenvatinib to a second-line agent and from a second-line agent to a third-line agent were 41.4% and 42.4%, respectively. Based on multivariate analysis, lenvatinib response was defined as complete or partial according to the modified Response Evaluation Criteria in Solid Tumors (mRECIST). Lenvatinib discontinuation due to radiological progression, according to mRECIST, was associated with a significantly higher probability of conversion to posttreatment after lenvatinib. Of the 63 patients who received second-line systemic therapy, 53 (84.1%) were administered sorafenib, with a PFS, response rate (RR), and disease control rate (DCR) of 1.8 months (95% CI: 0.6–3.0), 1.8%, and 20.8%, respectively. According to the Cox proportional hazards regression model, lenvatinib discontinuation due to radiological progression, Child–Pugh class B, and intrahepatic tumor volume > 50% at the time of sorafenib administration significantly contributed to a shorter PFS. Of the 22 patients who received regorafenib after lenvatinib discontinuation, five cases were as second-line therapy, and 17 were as third-line therapy. PFS, RR, and DCR for regorafenib treatment were 3.2 months (range, 1.5–4.9 months), 13.6%, and 36.3%, respectively. Conclusions: Sorafenib was not considered a candidate posttreatment agent after lenvatinib, except in a limited number of patients who discontinued lenvatinib without radiological progression. Regorafenib is a potential posttreatment agent after lenvatinib.

Impact of coronary plaque characteristics on periprocedural myocardial injury after elective percutaneous coronary intervention -MDCT and CMR analysis-

Background

Percutaneous coronary intervention (PCI) is often complicated by periprocedural myocardial injury (PMI) manifested by elevated cardiac biomarkers. The occurrence of PMI has been shown to be associated with worse clinical outcome over short- and long-term.

Purpose

We performed multidetector computed tomography (MDCT) and cardiac magnetic resonance imaging (CMR) to evaluate the relationship between culprit plaque characteristics and PMI.

Methods

A total of 90 patients who underwent elective PCI were underwent CMR and multidetector coronary tomography before PCI. The high intensity plaque (HIP) on CMR was defined as a coronary plaque to myocardium signal intensity ratio (PMR) of >1.4. The plaque characteristics and the presence of napkin-ring sign (NRS) were analyzed on MDCT. PMI was defined as an increase in cardiac Troponin T levels to more than 5 times the upper limit of normal at 24 h after PCI. Patients were divided into 2 groups according to the presence (Group I, n=26) or absence (Group II, n=64) of PMI.

Results

Spotty calcification, positive remodeling, low attenuation plaque and NRS on MDCT were significantly more observed in Group I than in Group II. HIP on CMR was significantly more observed in Group I than in Group II. In the multivariable logistic regression analysis, the presence of NRS and HIP were significantly independent predictors of PMI (odds ratio (OR) 4.82, 95% confidence interval 1.13–20.60, P=0.034 and OR 3.66, 95% CI 1.09–12.30, P=0.036, respectively). Moreover, for prediction of PMI, NRS and HIP showed a high positive predictive value of 81%, and their absence showed a high negative predictive value of 91%.

Conclusions

MDCT and CMR may play an important role in detecting which lesions are high risks for myocardial necrosis after PCI in elective coronary stenting.

Funding Acknowledgement

Type of funding source: None

Analyses of Intermediate-Stage Hepatocellular Carcinoma Patients Receiving Transarterial Chemoembolization prior to Designing Clinical Trials

BACKGROUND

Intermediate-stage hepatocellular carcinoma (HCC) has a high frequency of recurrence and progression to advanced stage after transarterial chemoembolization (TACE), particularly in patients with high tumor burden. Promising new results from immune checkpoint inhibitors (ICIs) and ICI-based therapies are expected to replace TACE, especially in HCC patients with high tumor burden.

AIMS

The present study aimed to evaluate the effectiveness of TACE with a view to design clinical trials comparing TACE and ICIs.

METHODS

We retrospectively identified intermediate-stage HCC patients undergoing TACE from our database and subdivided patients into low- and high-burden groups based on three subclassification models using the diameter of the maximum tumor and the number of tumors. Clinical outcomes were compared between low- and high-burden intermediate-stage HCC.

RESULTS

Of 1,161 newly diagnosed HCC patients, 316 were diagnosed with intermediate-stage disease and underwent TACE. The median overall survival from high-burden intermediate-stage disease was not significantly different by clinical course, reaching high tumor burden in all subclassification models. The prognosis of high-burden patients after initial TACE was poor compared with low-burden patients for two models (except for the up-to-seven criteria). In all three models, high-burden patients showed a poor durable response rate (DRR) both ≥3 months and ≥6 months and poor prognosis after TACE. Moreover, patients with confirmed durable response ≥3 months and ≥6 months showed better survival outcomes for high-burden intermediate-stage HCC.

CONCLUSIONS

Our results demonstrate the basis for selecting a population that would not benefit from TACE and setting DRR ≥3 months or ≥6 months as alternative endpoints when designing clinical trials comparing TACE and ICIs.

Potential of Lenvatinib for an Expanded Indication from the REFLECT Trial in Patients with Advanced Hepatocellular Carcinoma

BACKGROUND

The present study aimed to assess the efficacy and safety of lenvatinib and verify the possibility of lenvatinib for the expanded indication from the REFLECT trial in patients with advanced hepatocellular carcinoma (HCC) in real-world practice, primarily focusing on the population that was excluded in the REFLECT trial.

METHODS

We retrospectively collected data on patients with advanced HCC who were administered lenvatinib in 7 institutions in Japan.

RESULTS

Of 152 advanced HCC patients, 95 and 57 patients received lenvatinib in first-line and second- or later-line systemic therapies, respectively. The median progression-free survival in Child-Pugh class A patients was nearly equal between first- and second- or later-line therapies (5.2 months; 95% CI 3.7-6.9 for first line, 4.8 months; 95% CI 3.8-5.9 for second or later line, p = 0.933). According to the modified Response Evaluation Criteria in Solid Tumors, the objective response rate of 27 patients (18%) who showed a high burden of intrahepatic lesions (i.e., main portal vein and/or bile duct invasion or 50% or higher liver occupation) at baseline radiological assessment was 41% and similar with that of other population. The present study included 20 patients (13%) with Child-Pugh class B. These patients observed high frequency rates of liver function-related adverse events due to lenvatinib. The 8-week dose intensity of lenvatinib had a strong correlation with liver function according to both the Child-Pugh and albumin - bilirubin scores.

CONCLUSION

Lenvatinib had potential benefits for patients with advanced HCC with second- or later-line therapies and a high burden of intrahepatic lesions. Dose modification should be paid increased attention among patients with poor liver function, such as Child-Pugh class B patients.

Phase I study of a new concept cancer vaccine composed artificial intelligence (AI)-designed shared-antigen peptides plus combined synergistically activating antigen-specific CTL reaction (CYT001) in patients with advanced hepatocellular carcinoma (CRESCENT 1)

TPS595

Background: CYT001 (CYTLIMIC Inc.) is a novel cancer vaccine involving artificial intelligence (AI)-designed shared-antigen peptides and optimal combined adjuvants that boost the cancer-immunity cycle. The two multi-HLA reactive peptides heat shock protein 70 (HSP70) and glypican 3 (GPC3) were screened by an AI-based prediction system according to the proteome, mRNA, and histopathology data fromhuman samples. These immunogenic peptides were confirmed to show cross-reactivity to HLA-A 24:02, 02:01, and 02:06. Poly-ICLC (Oncovir Inc.) binds to Toll-like receptor 3 (TLR3) and melanoma differentiation antigen 5 (MDA5) on antigen-presenting cells (APCs)and activates APCs. LAG-3Ig (Immutep Inc.) binds to the major histocompatibility complex (MHC) class II molecules of APCs and activates APCs. Both poly-ICLC and LAG-3Ig synergistically activate antigen-specific CTL reactions as effective combination adjuvants. The present study aims to evaluate the safety and tolerability of CYT001 (mixture of HSP70 peptide [2.0 mg], GPC3 peptide [2.0 mg], poly-ICLC [1.0 mg], and LAG-3Ig [1.4 mg]) in patients with advanced hepatocellular carcinoma (HCC). Methods: This is a single-center, phase 1, open-label, single-arm, investigator-initiated clinical trial of CYT001 for advanced HCC patients with no eligible standard systemic therapy, Child–Pugh A liver disease, and HLA-A 24:02, 02:01, or 02:06. Enrolled patients will receive CYT001 as a subcutaneous injection on days 1, 8, 15, and 21 in the 1st and 2nd cycles, days 1 and 15 in the 3rd and 4th cycles, and day 1 in the 5th cycle or later of 28-day cycles. The primary endpoint is dose-limiting toxicity, and the secondary endpoints are safety and the response rate. The transition of the CTL reactions of both the HSP70 and GPC3 peptides will be evaluated using blood samples of the subjects. Exploratory analyses include investigation of candidate biomarkers for treatment efficacy using liver tumor biopsy samples (baseline and after the 1st cycle) and blood samples (baseline and every days of administration). Clinical trial information: jRCT2031190072.

Switching to systemic therapy after locoregional treatment failure: Definition and best timing

In patients with unresectable hepatocellular carcinoma (HCC) without both macrovascular invasion and extrahepatic metastasis, the initial treatment choice recommended is transarterial chemoembolization (TACE). Before sorafenib came into wide use, TACE had been pointlessly carried out repeatedly. It was in the early 2010s that the concept of TACE refractory was advocated. Two retrospective studies from Japan indicated that conversion from TACE to sorafenib the day after patients were deemed as TACE refractory improved overall survival compared with continued TACE, according to the definition by the Japan Society of Hepatology. Nowadays, phase 3 trials have shown clinical benefits of several novel molecular target agents. Compared with the era of sorafenib, sequential treatments with these molecular target agents have gradually prolonged patients’ survival and have become major strategies in patients with HCC. Taking these together, conversion from TACE to systemic therapies at the time of TACE refractory, compared with before, may have a greater impact on survival and may be considered deeper in the decisions-making process in patients with unresectable HCC who are candidate for TACE. Up-to-date information on the concept of TACE refractory is summarized in this review. We believe that the survival of patients with unresectable HCC without both macrovascular invasion and extrahepatic metastasis may be dramatically improved by optimal timing of TACE refractory and switching to systemic therapies.

Long-term administration of Tolvaptan to patients with decompensated cirrhosis

Aim: Tolvaptan, an oral vasopressin-2 antagonist, sometimes improves hepatic edema including ascites in patients with decompensated cirrhosis. In this study, we examined the effectiveness and survival advantage in patients with the long-term administration of tolvaptan. Methods: A total of 115 patients with refractory ascites who were treated with tolvaptan were retrospectively analyzed based on their clinical records. Patients with a decrease in body weight of ≥1.5 kg from the baseline on day 7 were determined as responders. Re-exacerbation was defined as a return to the baseline BW, dose escalation of conventional diuretics, or abdominal drainage. Results: Of the 115 patients, 84 were included in this analysis. Response to tolvaptan treatment was observed in 55 out of the 84 patients (65.5%), with a mean weight reduction of 2.52 kg. Multivariate analyses demonstrated that body mass index (≥24) and urinary specific gravity (≥1.018) were significant predictors of the response to tolvaptan. However, cumulative re-exacerbation rates in responders at 6 and 12 months were 42.4 and 60.1%, respectively. Child-Pugh (classification C), HCC complication, and serum sodium levels (≥133 mEq/L) were determined as independent prognostic factors impacting overall survival (OS). Although there were no significant differences in OS between tolvaptan responders and non-responders, the responders without re-exacerbation within 3 months showed significantly longer OS than those with re-exacerbation within 3 months. Conclusion: A persistent therapeutic response, but not early response to tolvaptan, was associated with favorable survival of decompensated cirrhotic patients.

Serum fibroblast growth factor 19 serves as a potential novel biomarker for hepatocellular carcinoma

Background

Abnormal autocrine fibroblast growth factor 19 (FGF19) production has been observed in several types of cancers, including hepatocellular carcinoma (HCC). In this study, we investigated the potential of serum FGF19 as a novel tumor marker of HCC based on a sandwich enzyme-linked immunosorbent assay (ELISA).

Methods

The serum FGF19 levels of 304 patients with HCC was measured by ELISA. The serum levels of existing markers, including alpha-fetoprotein (AFP) and des-gamma-carboxy prothrombin (DCP) were determined by chemiluminescence enzyme immunoassay. Both diagnostic value of FGF19 and its changes after curative ablation therapy was further examined.

Results

The median FGF19 levels in controls, chronic liver disease patients, and primary HCC patients, were 78.8 pg/mL, 100.1 pg/mL, and 214.5 pg/mL, respectively. The subsequent receiver operating characteristic curves (ROC) successfully determined an optimal cut-off value of 200.0 pg/mL. The area under the ROC curve (AUC) of FGF19 for HCC detection was comparable to those of AFP and DCP. Of importance, FGF19 showed higher sensitivity for the detection of small HCC (solitary cancer with diameter < 20 mm) than those of existing markers. In addition, 43 out of 79 cases (54.4%) with normal AFP and DCP (so-called “double negative HCC”) exhibited serum FGF19 level ≥ 200 pg/mL. In 45 HCC patients treated with curative ablation therapy, serum FGF19 levels changed from 257.4 pg/mL to 112.0 pg/mL after the treatment.

Conclusion

Our findings reveal that FGF19 can be a potential novel biomarker for HCC. Although FGF19 is not necessarily a substitute for existing markers, it may help improve the prognosis in HCC patients owing to its resourceful use in various aspects of HCC management and treatment.

Simultaneous chylous ascites and chylothorax during ramucirumab plus docetaxel chemotherapy in a patient with non-small lung cell cancer

A 69-year-old woman was diagnosed as having non-small cell lung cancer (adenocarcinoma, T1aN3M1b). She had no history of surgery or abdominal trauma. She was treated with ramucirumab (10 mg/kg) plus docetaxel (60 mg/m²) intravenously (RAM + DTX) every 3 weeks. Although an enhanced CT examination showed a partial tumor response after eight courses of RAM + DTX, she gradually began to experience abdominal fullness with severe peripheral pitching edema. Her body weight increased by 18 kg in 2 months and RAM + DTX chemotherapy was discontinued. An enhanced CT examination showed a large amount of ascites and pleural effusion, with no obstructions of the central vein or lymphatic ducts. The ascites were white and milky in appearance and contained 527 mg/dL of triglyceride. In addition, her pleural effusion was also white and milky in appearance. No further increases in ascites and pleural effusion were observed thereafter. Four months after her last RAM + DTX chemotherapy, she continued to exhibit a partial response and no increases in ascites or pleural effusion were present. The chylous effusion might have been caused by the RAM + DTX chemotherapy.

Sequential therapy with sorafenib and regorafenib for advanced hepatocellular carcinoma: a multicenter retrospective study in Japan

Background Conversion from sorafenib to regorafenib is primarily an evidence-based treatment strategy in patients with advanced hepatocellular carcinoma (HCC). This study aimed to assess the safety and efficacy of sequential therapy with sorafenib and regorafenib in patients with advanced HCC by analysis of outcomes in clinical practice with the aim to complement phase III findings. Methods The medical records of patients with advanced HCC receiving regorafenib were retrieved to collect data on sorafenib administration at seven Japanese institutions. Radiological responses and adverse events were evaluated using the Response Evaluation Criteria in Solid Tumors version 1.1 and the Common Terminology Criteria for Adverse Events version 4.0, respectively. Results Before March 2018, 44 patients were administered regorafenib for advanced HCC. The median sorafenib treatment duration was 8.4 months. The most common adverse events were similar to those reported by the RESORCE trial. The median overall survival (OS) was 17.3 months (95% confidence interval [CI] 11.4-22.9), and 17 of 37 patients (45.9%) discontinued regorafenib and received sequential systemic therapy after regorafenib. These patients had significantly longer OS than those who were treated by the best supportive care or sub-optimal therapy (not reached versus 8.7 months [95% CI 5.8-11.7]; P < 0.001). Conclusion The results based on Japanese clinical practices verified the tolerability of regorafenib in advanced HCC. Major regorafenib-associated adverse events were similar to those related to sorafenib. OS was significantly longer than expected, which might be associated with the sequential systemic therapies after regorafenib, mainly lenvatinib.

Conformational changes in the unique loops bordering the ATP binding cleft of skeletal muscle myosin mediate energy transduction

Myosin has three highly-conserved, unique loops [B (320-327), M (677-689), and N (127-136)] at the entrance of the ATP binding cleft, and we previously showed that the effects of actin are mediated by a conformational change in loop M [Maruta and Homma (1998) J. Biochem. 124, 528-533]. In the present study, loops M and N were photolabeled respectively with fluorescent probes Mant-8-N(3)-ADP and Mant-2-N(3)-ADP in order to study conformational changes in the loops related to energy transduction. The effect of actin on the conformation of loop N was examined by analyzing fluorescence polarization and acrylamide quenching; the results were then compared with those previously reported for loop M. In contrast to loop M, the fluorescence polarization and the value of K(sv) of the Mant-groups crosslinked to loop N were slightly affected by actin binding. To study conformational changes in loops M and N during the ATPase cycle, FRET was analyzed using TNP-ADP.BeFn and TNP-ADP. AlF(4)(-) as FRET acceptors of Mant fluorescence. The resultant estimated distances between loop M and the active site differed for the Mant-S1.TNP-ADP.BeFn and Mant-S1.TNP-ADP.AlF(4)(-) complexes, whereas the distances between loop N and the active site differed slightly. These findings indicate that the conformation of loop M changes during the ATPase cycle, suggesting that Loop M acts as a signal transducer mediating communication between the ATP- and actin-binding sites. Loop N, by contrast, is not significantly flexible.

Solution structure of myosin-ADP-MgFn ternary complex by fluorescent probes and small-angle synchrotron X-ray scattering

In the presence of excess amounts of fluorine, a physiological divalent cation, magnesium (Mg(2+)), forms a novel phosphate analogue, magnesium fluoride (MgFn). Park et al. [Biochim. Biophys. Acta 1430, 127-140 (1999)] previously demonstrated that MgADP. MgFn forms a complex with myosin subfragment-1 (S-1), and the S-1.ADP. MgFn ternary complex mimics a transient state in the activity cycle of ATPase. In the present study, localized conformations in the regions of highly reactive cysteine and lysine residues, Cys 707 (SH1), Cys 697 (SH2), and Lys 83 (RLR), which change their conformations markedly during ATP hydrolysis, were studied using fluorescent probes and chemical modification. The global shape of the complex was also studied using small angle X-ray solution scattering and compared it with other previously reported myosin.ADP. fluorometal ternary complexes. The results suggest that the overall conformation and localized functional regions of the complex are quite similar to those in the presence of ATP, indicating that the complex mimics the M(**).ADP.P(i) steady state.

Analysis of conformational changes at the unique loop adjacent to the ATP binding site of smooth muscle myosin using a fluorescent probe

Recent crystallographic studies have shown that smooth muscle myosin has three highly conserved unique loops, loop B (320-327), loop M (687-699), and loop N (125-134), similar to other myosins, skeletal muscle and dictyostelium myosins. We previously demonstrated that the effect of actin is mediated by a conformational change in one of the loops, loop M comprising amino acids 677 to 689 of skeletal muscle myosin [Maruta and Homma (1998) J. Biochem. 124, 528-533]. In the present study, in order to clarify the role of these smooth muscle myosin loops in energy transduction, we specifically labeled the loops with a fluorescent photoreactive ADP analogue, 3'-O-(N-methylanthraniloyl)-8-azido-ADP (Mant-8-N(3)-ADP), and then measured the fluorescent polarization. When Mant-8-N(3)-ADP was trapped by aluminium fluoride or vanadate into the ATPase site, Mant-8-N(3)-ADP was covalently incorporated into loop N (125-134). In contrast, Mant-8-N(3)-ADP trapped by beryllium fluoride was covalently incorporated into both loop M (687-699) and loop N (125-134) at an almost equimolar ratio. Actin binding to smooth muscle myosin S1 (SMO-S1) labeled at only loop N (125-134) increased the polarization due to the viscosity of actin. In contrast, S1 labeled at both loops N and M showed a much smaller increase in polarization. Our results indicate that the probe at loop M (687-699) of smooth muscle myosin moved to a less hindered region, suggesting that actin binding induces conformational changes at loop M (687-699) similar to those of the corresponding loop (677-689) in skeletal muscle myosin, as previously demonstrated in our laboratory.

Formation of the myosin.ADP.gallium fluoride complex and its solution structure by small-angle synchrotron X-ray scattering

In the presence of MgADP, a novel phosphate analogue of gallium fluoride (GaFn) forms a ternary complex with the myosin subfragment-1 (S-1), in the same way that has been previously reported with aluminum fluoride (AlF4-), beryllium fluoride (BeFn), scandium fluoride (ScFn), and vanadate (Vi), and this complex formation may mimic different states along the ATPase kinetic pathway. This novel complex has been characterized and compared with other complexes to ascertain whether it forms a transition-state analogue of myosin ATPase. The complex formed quickly, although several times slower than the BeFn complex. The half-life of the myosin.ADP.GaFn complex was about 50 h at 4 degreesC. The formation of the myosin.ADP.GaFn complex was accompanied by an increase in tryptophane fluorescence, similar to that observed upon the addition of ATP, but slightly lower than that of the M**.ADP.Pi complex. Upon addition of GaFn to acto-myosin.ADP, acto-myosin did not dissociate, and the S-1.ADP.GaFn complex was scarcely decomposed by actin, like the AlF4- and ScFn complexes but unlike the BeFn and Vi complexes. The conformations at the localized region of SH1, SH2, and RLR, which are very accessible to the binding of ATP, were studied by fluorescent labeling and chemical modification, and the results suggested that these conformations are very similar to that of the M**.ADP.Pi state. Small-angle X-ray solution scattering showed that the radius of gyration value decreases by about 3 A when S-1 forms an S-1.ADP.GaFn complex, suggesting that the shape of the complex becomes compact or rounded in shape, similar to that in the presence of ATP or complexes with other phosphate analogues, and thus mimics the myosin**.ADP.Pi state closely. The overall results may indicate that the complex mimics a somewhat different transient state from that of other complexes but has a similar global conformation along the ATPase kinetic pathway.

ADP/vanadate mediated photocleavage of myosin light chain kinase at the autoinhibitory region

The vanadate (Vi)-mediated photocleavage reaction was used to study the interaction between the regulatory segment and the catalytic site of smooth muscle myosin light chain kinase (MLCK). When MLCK was irradiated with long-wave UV (366 nm) in the presence of ADP and Vi, kinase activity was substantially decreased, and the MLCK polypeptide of 130 kDa was cleaved into several smaller fragments with apparent molecular masses of 100, 70, 60, 32, and 28 kDa. Inhibition of kinase activity and photocleavage were both competitively antagonized by the addition of ATP. Inconsistency between the observed maximum levels of UV-induced inhibition of MLCK-mediated phosphorylation (80%) and photocleavage (15-20%) suggested that the photocleavage reaction proceeds as a two-step process. Monoclonal antibodies recognizing the C-terminus of MLCK labeled the 60- and 28-kDa fragments, indicating that MLCK was cleaved at two sites, at 28 and 60 kDa from the C-terminus, within what are believed to be the autoinhibitory region and the catalytic site, respectively. Moreover, Ca2+-calmodulin (Ca2+-CaM) protected against cleavage at the site at 28 kDa from the C-terminus. Analysis of the amino acid composition of the fragment revealed that the cleavage site at 28 kDa from C-terminus occurred at Lys 799 +/- 3 amino acid residues, which is in a region where the CaM-binding and pseudosubstrate regions overlap. These results suggest that the three-dimensional structure of MLCK brings the regulatory segment into direct contact with the ATP-binding site. Moreover, the binding of Ca2+-CaM displaces the regulatory segment away from the catalytic site.

A unique loop contributing to the structure of the ATP-binding cleft of skeletal muscle myosin communicates with the actin-binding site

Actin binding to skeletal muscle myosin subfragment-1 (S1) increases the dissociation rate of reaction products from the myosin ATPase site; conversely, ATP binding facilitates dissociation of complexed acto-S1. However, details of the molecular mechanism by which the ATP- and actin-binding sites communicate with each other is still obscure. We present evidence that the effect of actin is mediated by a conformational change in the loop containing amino acids from 677 to 689 [loop M (677-689)], a segment of the 20-kDa tryptic fragment that contributes to the structure of the ATP-binding cleft. Initially, a fluorescent ADP analogue, methylanthranyloyl-8-azido-ADP (Mant-8-N3-ADP), was covalently crosslinked to loop M (Mant-S1), perhaps at Lys 681. Actin-activated Mg2+-ATP hydrolysis by Mant-S1 was accelerated approximately 6 times over that by unmodified S1, suggesting that the ATPase site is not blocked by the ADP analogue crosslinked in the loop M (677-689). Nevertheless, analysis of Mant-group fluorescence polarization and acrylamide-induced quenching showed the crosslinked probe to be entrapped within the ATP-binding cleft at a location where Mant-group rotational mobility was hindered, and where it was relatively inaccessible to the solvent. Exposing Mant-S1 to Mg2+-ATP and/or actin elicited similar decreases in fluorescence polarization, indicating increased rotational mobility of the Mant-group and movement of crosslinked Mant-8-N3-ADP to a less hindered position. Stern-Volmer quench curves showed that Mant-8-N3-ADP was translocated to a site where it was more accessible to dissolved quencher, perhaps outside the ATP-binding cleft. Since actin does not bind to the ATPase site, actin-induced translocation of Mant-8-N3-ADP crosslinked to loop M (677-689) probably results from a conformational change in loop M (677-689). These results suggest that loop M acts as a signal transducer mediating communication between the ATP- and actin-binding sites.

Conformational changes at the highly reactive cystein and lysine regions of skeletal muscle myosin induced by formation of transition state analogues

Myosin forms stable ternary complexes with Mg2+-ADP and phosphate analogues of aluminum fluoride (AlF4-), beryllium fluoride (BeFn), and scandium fluoride (ScFn). These complexes are distinct from each other and may mimic different transient states in the ATPase cycle [Maruta et al. (1993) J. Biol. Chem. 268, 7093-7100]. Regions of skeletal muscle myosin containing the highly reactive residues Cys 707 (SH1), Cys 697 (SH2), and lysine 83 (RLR) dramatically alter their local conformation when myosin hydrolyzes ATP, and these changes may reflect formation of a series of transient intermediates during ATP hydrolysis. We used the fluorescent probes 4-fluoro-7-sulfamoylbezofurazan, 2-(4'-maleimidylanilino)naphthalene-6-sulfonic acid, and trinitrobenzene-sulfonate, which bind to SH1, SH2, and RLR, respectively, to examine differences in local conformations within myosin.ADP.phosphate analogue (BeFn, Vi, AlF4-, and ScFn) complexes. It was observed that the ternary complexes had SH1 conformations similar to those seen on S-1 in the presence of ATP. In contrast, local conformations in the SH2 and RLR regions of S-1.ADP.BeFn were different from those in corresponding regions of S-1.ADP.AlF4- or ScFn. These results suggest that SH1 and SH2 move distinctly during ATP hydrolysis and that the local conformations of the SH2 and RLR regions more sensitively reflect different transient states.

Characterization of the interaction of myosin with ATP analogues having the syn conformation with respect to the adenine-ribose bond

Numerous analytical experiments have shown that, in solution, ATP analogues with bulky substitutions at the eighth position of the adenine ring predominantly assume the syn conformation with respect to the adenine-ribose bond. Two such analogues, 3'-O-(N-methylanthraniloyl)-8-azido-ATP (Mant-8-N3-ATP) and 8-Br-ATP, were synthesized and used to probe the conformation of the ATP-binding site of myosin. In the presence of these analogues, actomyosin was rapidly dissociated; Mg2+-dependent ATP hydrolysis was significantly activated by actin; and Pi bursting was observed. For skeletal myosin, however, these analogues failed to support actin translocation, and they did not significantly enhance the intrinsic tryptophan fluorescence of skeletal muscle myosin subfragment-1 (SKE S-1). These results suggest that although myosin**/ADP/Pi intermediates can be formed with these analogues, the crucial conformational changes required for cross-bridge cycling do not occur in skeletal muscle myosin. The conformations of the ATP-binding sites of skeletal and smooth-muscle myosin were compared using the ternary complexes, myosin-ADP-beryllium fluoride (BeFn) or myosin-ADP-aluminium fluoride (AIF4-). In AlF4- complexes, Mant-8-N3-ADP affinity labeled the N-terminal 29-kDa domain of smooth-muscle myosin subfragment-1 (SM S-1), as did ATP analogues having the anti conformation, whereas it labeled the C-terminal 20-kDa domain of skeletal S-1. In smooth muscle BeFn complexes, Mant-8-N3-ADP was equally likely to cross-link to the 29-kDa N-terminal and the 25-kDa C-terminal domains. These analogues induced smooth muscle actomyosin super-precipitation and increased intrinsic tryptophan fluorescence to the same degree as ATP itself. As was expected from above results, the analogues supported smooth-muscle-myosin-induced actin translocation. These results suggest that smooth-muscle myosin adopts the eight-substituted ATP analogue in the normal conformation, but skeletal muscle myosin does not. This reflects the likely differences in the structures of their respective ATPase sites.

Analysis of stress in the active site of myosin accompanied by conformational changes in transient state intermediate complexes using photoaffinity labeling and 19F-NMR spectroscopy

Myosin forms stable ternary complexes with ADP and the phosphate analogues, fluoroaluminate (Al F4-), fluoroberyllate (BeFn) or orthovanadate (Vi); these ternary complexes mimic transient intermediates in the myosin ATPase cycle. Moreover, we previously demonstrated that these complexes may mimic different myosin ATPase reaction intermediates corresponding to separate steps in the cross-bridge cycle [Maruta, S., Henry, G. D., Sykes, B. D. & Ikebe, M. (1993) J. Biol. Chem. 268, 7093-7100]. Park et al. suggested that the changing conformation of ATP during hydrolysis stresses the active site of myosin subfragment-1 (S-1) through protein-nucleotide contacts at the gamma-phosphate and nucleotide base, and the stress-induced strain in the cross-bridge may be the mechanism by which energy in ATP is transferred to the myosin structure [Park, S., Ajtai, K. & Burghardt, T. P. (1997) Biochemistry 36, 3368-3372]. In the present study, the photoactive ADP analogue, 3'-O-(N-methylanthraniloyl)-2-azido-ADP (Mant-2-N3-ADP), and the 19F-labeled ADP analogue, 2-[(trifluoromethylnitrophenyl)aminoethyl]diphosphate, were employed to examine conformational differences in protein-nucleotide contact in the ATP-binding site that may correlate with energy transduction. Mant-2-N3-ADP was trapped within the active site of skeletal and smooth muscle myosin in the presence of AlF4-, BeFn or Vi. For both skeletal and smooth muscle myosins, trapped Mant-2-N3-ADP was covalently linked to the 25-kDa N-terminal fragment of S-1 of both myosin/Mant-2-N3-ADP/AlF4- and BeFn complexes, presumably at Trp130. However, the efficiency of the incorporation was much higher for skeletal than for smooth muscle myosin suggesting that the conformations of the adenine-binding pockets of the two myosins are somewhat different. Although the amount of Mant-2-N3-ADP trapped in the presence of AlF4- and BeFn was the same for both myosins, the efficiency of photolabeling skeletal muscle myosin was approximately two times higher for BeFn complex than for AlF4- complex. The 19F-NMR spectra of the bound 2-[(trifluoromethylnitrophenyl)aminoethyl]diphosphate in the ternary complexes formed in the presence of AlF4-, BeFn or Vi showed small but distinguishable differences. Taken together, these results indicate that there is some variation in the protein-nucleotide contacts at the nucleotide base among the ternary complexes studied, and these differences mimic separate steps occurring transiently during the contractile cycle.

A case of early cancer in cystic intrahepatic duct associated with congenital choledochal cyst

Herein, we report an extremely rare case of early cancer localized in the cystic intrahepatic duct, which is associated with the choledochal cyst including both the intra- and extrahepatic duct (type IV-A cyst). A small polypoid lesion in the cyst was detected by computed tomography. Extensive resection of the choledochal cyst with lobectomy was performed on the tumor in a 23-year-old woman. Tubular adenocarcinoma localized in the wall of the cystic left hepatic duct was histologically confirmed. Awareness of the diagnostic and treatment modalities, with a focus on potential malignancy in the cystic intrahepatic duct, in cases with anomalous arrangement of the pancreatobiliary duct is necessary.

The coexistence of esophageal submucosal tumor and carcinoma

The coexistence of esophageal submucosal tumor and carcinoma has been reported only in very few cases up to now, and the relationship between them is unclear. To elucidate the incidence and the pathogenesis of their coexistence, endoscopy and endoscopic ultrasonography (EUS) were sequentially performed in 95 patients who were suspected of having a submucosal tumor of the esophagus. EUS revealed 83 submucosal tumors and 12 cases of extraluminal compression. Two cases of esophageal carcinoma were observed in the series. In one patient, intraepithelial carcinoma was present on a leiomyoma originating in the muscularis mucosae, and in the other patient, multiple superficial carcinomas were presented.

Superficial esophageal carcinoma: evaluation by endoscopic ultrasonography

OBJECTIVES

The aim of this study was to evaluate the usefulness of endoscopic ultrasonography (EUS) in the staging of superficial esophageal carcinoma (SEC).

METHODS

We examined the histopathologic findings of 28 patients with SEC which was confirmed in the postoperative histologic evaluation. The EUS results preoperatively estimated were compared with them.

RESULTS

There were nine patients with mucosal carcinoma (two intraepithelial carcinomas and seven carcinomas limited to the mucosal layer) and 19 patients with submucosal carcinoma. The mucosal carcinomas revealed no lymph node metastasis or vessel permeation, whereas the submucosal carcinomas revealed lymph node metastasis (71%) and vessel permeation (lymphatic, 58%, vascular, 21%). The accuracy rates of depth of invasion by EUS were mucosa, 67% (6/9); submucosa, 79% (15/19); and total, 75% (21/28). EUS could not detect microinvasion to the submucosa. The overall accuracy rate of EUS in the evaluation of periesophagogastric lymph node metastasis was 72%: sensitivity 58% and specificity 85%.

CONCLUSIONS

It has been clinically proved important to differentiate mucosal carcinoma from submucosal carcinoma in the staging of SEC, and EUS is recommended in differentiating between them.

Observation of multiple myosin subfragment 1-ADP-fluoroberyllate complexes by 19F NMR spectroscopy

Fluoroaluminate and fluoroberyllate are potent inhibitors of the ATPase activity of myosin. Inhibition requires the presence of ADP, and much evidence has accumulated to suggest that the tetrahedral fluoroaluminate and fluoroberyllate ions act as phosphate analogues, binding with high affinity at the active site in the position normally occupied by the terminal phosphate of ATP. Both the S1-ADP-fluoroaluminate and the S1-ADP-fluoroberyllate species are thought to resemble kinetic intermediates in the actomyosin ATPase cycle. Characterization of S1-bound fluoroaluminate by 19F NMR is straightforward; a single resonance identified as AlF4- is observed easily [Maruta, S., Henry, G.D., Sykes, B.D., & Ikebe, M (1993) J. Biol. Chem. 268, 7093-7100]. Bound fluoroberyllate, by contrast, was found to give rise to four separate peaks: a downfield pair at -80 and -83.5 ppm and an upfield pair at -101.5 and -103 ppm, suggesting the existence of four distinct types of S1-ADP-fluoroberyllate complex. The relative intensities of the bound resonances can be altered by changing rhe F:Be ratio during complex formation. Integration of a spectrum acquired in the presence of a fluorine-labeled nucleotide derivative, 3'(2')-O-(4-fluorobenzoyl)-ADP, in place of ADP yielded a bound fluoride to nucleotide ratio of 1.7-1.9 to 1, showing that the major bound fluoroberyllate species cannot be BeF3- as is usually thought. It is proposed that the bound fluoroberyllates correspond to the neutral species BeF2(H2O)2 and BeFOH(H2O)2 and the negatively charged species [BeF2OH.H2O]- and [BeF3.H2O]-, although other possibilities are discussed.

Photoaffinity labelling of smooth-muscle myosin by methylanthraniloyl-8-azido-ATP

Methylanthraniloyl-8-azido-ATP (Mant-8-N3-ATP), which binds to the 20 kDa C-terminal tryptic fragment of skeletal-muscle myosin subfragment-1 [Maruta, Miyanishi and Matsuda (1989) Eur. J. Biochem. 184, 213-221], was synthesized and used as a probe of the conformational change of smooth-muscle myosin. Mant-8-N3-ATP, like ATP, induced the formation of the 10 S conformation at low ionic strength. In the presence of vanadate, smooth-muscle myosin formed a stable complex with Mant-8-N3-ADP, and this complex showed the 10 S-->6 S transition of myosin. ATP-binding sites for 6 S (extended state) and 10 S (folded state) myosin were studied by photolabelling of myosin with Mant-8-N3-ADP. For both 6 S and 10 S myosin, Mant-8-N3-ATP was incorporated into the 29 kDa N-terminal tryptic fragment of myosin heavy chain. This is unlike the labelling of skeletal-muscle myosin, in which the 20 kDa C-terminal fragment is labelled. The labelling of 29 kDa fragment was diminished significantly by addition of ATP. These results suggest that the conformation of the ATP-binding site of smooth-muscle myosin is different from that of skeletal-muscle myosin. To examine further the possible differences in the labelling site between 6 S and 10 S myosin, the affinity-labelled 29 kDa fragment was subjected to complete proteolysis by lysylendo-peptidase. The fluorescent-labelled-peptide map suggested that the Mant-8-N3-ADP-binding sites for 6 S and 10 S myosin were identical.

Formation of the stable myosin-ADP-aluminum fluoride and myosin-ADP-beryllium fluoride complexes and their analysis using 19F NMR

The effects of aluminum fluoride and beryllium fluoride on smooth muscle myosin and its subfragments were studied. Mg(2+)-ATPase activity was inhibited in the presence of aluminum fluoride (beryllium fluoride). [3H]ADP bound to heavy meromyosin (HMM) in the presence of aluminum fluoride (beryllium fluoride) and was not dissociated after 3 days of dialysis demonstrating that [3H]ADP was trapped in HMM. These results suggest the formation of a stable HMM-ADP-fluoroaluminate (fluoroberyllate) complex. The intrinsic tryptophane fluorescence intensity was increased in the presence of ADP and aluminum fluoride (beryllium fluoride). Acto-S1 was dissociated upon the formation of S1-ADP-fluoroberyllate and actin destabilized S1-ADP-fluoroberyllate complex, while S1-ADP-fluoroaluminate failed to bind to actin. Furthermore, when S1 formed the complex with actin, nucleotide trapping did not occur in the presence of fluoraluminate. These results indicated that the myosin-ADP-fluoroberyllate complex resembles a weak binding state while myosin-ADP-fluoroaluminate complex is a distinct conformation although the binding to actin was also weak. The structure of the ternary complex was investigated using 19F NMR. The 19F NMR spectrum of the S1-ADP-fluoroaluminate complex showed a peak at -66.7 ppm which is due to the binding of fluoraluminate to S1. The peak was not observed when 5'-adenylylimidodiphosphate was substituted for ADP suggesting that aluminum fluoride plays a role as a phosphate analogue. The stoichiometry of the bound fluoride was determined to be 3.8 mol/mol S1 suggesting that the bound species is AlF-4.

Endoscopic ultrasonography for assessing the horizontal extent of invasive gastric carcinoma

Accurately determining the surgical resection line is essential for improving the prognosis of patients with gastric carcinoma. Endoscopic ultrasonography (EUS) was used to assess the horizontal extent of cancerous invasion below the mucosal layer. In 105 patients (110 lesions) with gastric carcinoma, ultrasonographic images of resected specimens were compared with histological findings. The horizontal extent of the hypoechoic region of in vitro ultrasound was compared with the horizontal extent of the cancerous invasion and fibrosis in histological sections. In cases showing echo patterns characteristic of peptic ulcerations within the tumor focus, the horizontal spread of the echo-poor region correlated well with the spread of fibrosis, but not with the cancerous lesion. In other cases with no ulceration, the horizontal spread of the echo-poor region corresponded well with the cancerous lesions. To evaluate oral invasion of the cancerous lesion below the mucosa, 16 patients with gastric carcinoma who had clips placed during endoscopy were subsequently examined by EUS. The use of EUS combined with the clips allowed for a more accurate diagnosis of the invasion, not only in the mucosa, but also into the submucosa and beyond. This combined diagnostic method was safe and useful for determining a suitable surgical resection line.

Cross-linking of the 25- and 20-kilodalton fragments of skeletal myosin subfragment 1 by a bifunctional ATP analogue

The bifunctional photoreactive ATP analogue azidonitrobenzoyl-8-azido-ATP (ANB-8-N3-ATP) was synthesized. This ATP analogue carriers photoreactive azido groups at the eighth position of the adenine ring and at the 3' position of ribose. Photolysis of this analogue in the presence of skeletal muscle alpha-chymotryptic subfragment 1 (S-1) resulted in a new 120-kDa band, while photolysis in the presence of the tryptic S-1 produced a new 45-kDa band. The 45-kDa peptide was shown to be combined with the 25-kDa N-terminal and 20-kDa C-terminal fragments since it was labeled with a monoclonal antibody specific for the N-terminal 25-kDa segment of the S-1 heavy chain, and it was also found to retain the fluorescence of (iodoacetamido)fluorescein attached specifically to the SH-1 thiol of the C-terminal 20-kDa segment. These results indicate that the 25- and 20-kDa peptides are in close contact with the ATPase active site.

A second consensus sequence of ATP-requiring proteins resides in the 21-kDa C-terminal segment of myosin subfragment 1

Previous comparisons of sequence homologies of ATP-requiring enzymes have defined three consensus sequences which appear to be involved in the binding of the nucleotide. One of these was identified in the N-terminal 27-kDa segment of the myosin heavy chain but the other two sequences have not hitherto been located in myosin. The present paper proposes that one of these other two consensus sequences is in the 21-kDa C-terminal portion of S1 and that it may contribute to the ATP binding domain.

Hyposmolar stimulation of secretion of thyrotropin, prolactin, and luteinizing hormone does not require extracellular calcium and is not inhibited by colchicine, cytochalasin B, ouabain, or tetrodotoxin

Hyposmolar stimulation of thyroid-stimulating hormone, prolactin, and luteinizing hormone secretion by dispersed perifused rat pituitary cells was not depressed by removal of Ca2+ from the perifusion medium or by 0.1 mM colchicine, 20 microM cytochalasin B, 0.1 mM ouabain, or 3 microM tetrodotoxin. The secretory response induced by medium hyposmolarity or by thyrotropin-releasing hormone was not appreciably different at 23, 37, or 43 degrees C, but was markedly reduced or abolished when the experiments were performed at 1 degree C. These data indicate that microtubules or microfilaments, transport of extracellular Ca2+ into the cytoplasm, and plasmalemma ion transport mechanisms sensitive to ouabain or tetrodotoxin are not essential components of the mechanism by which extracellular hyposmolarity induces secretion.