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.

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 (TGKR) 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 TGKR, 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 TGKR. 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.

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.

Bmi1 promotes hepatic stem cell expansion and tumorigenicity in both Ink4a/Arf-dependent and -independent manners in mice.

UNLABELLED: We previously reported that forced expression of Bmi1 (B lymphoma Moloney murine leukemia virus insertion region 1 homolog) in murine hepatic stem/progenitor cells purified from fetal liver enhances their self-renewal and drives cancer initiation. In the present study, we examined the contribution of the Ink4a/Arf tumor suppressor gene locus, one of the major targets of Bmi1, to stem cell expansion and cancer initiation. Bmi1(-/-) Delta-like protein (Dlk)(+) hepatic stem/progenitor cells showed de-repression of the Ink4a/Arf locus and displayed impaired growth activity. In contrast, Ink4a/Arf(-/-) Dlk(+) cells gave rise to considerably larger colonies containing a greater number of bipotent cells than wild-type Dlk(+) cells. Although Ink4a/Arf(-/-) Dlk(+) cells did not initiate tumors in recipient nonobese diabetic/severe combined immunodeficiency mice, enforced expression of Bmi1 in Ink4a/Arf(-/-) Dlk(+) cells further augmented their self-renewal capacity and resulted in tumor formation in vivo. Microarray analyses successfully identified five down-regulated genes as candidate downstream targets for Bmi1 in hepatic stem/progenitor cells. Of these genes, enforced expression of sex determining region Y-box 17 (Sox17) in Dlk(+) cells strongly suppressed colony propagation and tumor growth. CONCLUSION: These results indicate that repression of targets of Bmi1 other than the Ink4a/Arf locus plays a crucial role in the oncogenic transformation of hepatic stem/progenitor cells. Functional analyses of Bmi1 target genes would be of importance to elucidate the molecular machinery underlying hepatic stem cell system and explore therapeutic approaches for the eradication of liver cancer stem cells.

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.

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.

The polycomb gene product BMI1 contributes to the maintenance of tumor-initiating side population cells in hepatocellular carcinoma.

Side population (SP) cell analysis and sorting have been successfully applied to hepatocellular carcinoma (HCC) cell lines to identify a minor cell population with cancer stem cell properties. However, the molecular mechanisms operating in SP cells remain unclear. The polycomb gene product BMI1 plays a central role in the self-renewal of somatic stem cells in a variety of tissues and organs and seems to be implicated in tumor development. In this study, we determined the critical role of BMI1 in the maintenance of cancer stem cells with the SP phenotype in HCC cell lines. BMI1 was preferentially expressed in SP cells in Huh7 and PLC/PRF/5 HCC cells compared with the corresponding non-SP cells. Lentiviral knockdown of BMI1 considerably decreased the number of SP cells in both Huh7 and PLC/PRF/5 cells. Long-term culture of purified SP cells resulted in a drastic reduction in the SP subpopulation upon the BMI1 knockdown, indicating that BMI1 is required for the self-renewal of SP cells in culture. More importantly, the BMI1 knockdown abolished the tumor-initiating ability of SP cells in nonobese diabetic/severe combined immunodeficiency mice. Derepression of the INK4A and ARF genes that are major targets for BMI1 was not necessarily associated with impaired self-renewal of SP cells caused by BMI1 knockdown. In conclusion, our findings define an important role for BMI1 in the maintenance of tumor-initiating SP cells in HCC. BMI1 might be a novel therapeutic target for the eradication of cancer stem cells in HCC.