ORCID Profile
0000-0003-1596-4200
Current Organisation
Keio University School of Medicine
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Publisher: BMJ
Date: 11-2020
Abstract: Combining inhibitors of vascular endothelial growth factor and the programmed cell death protein 1 (PD1) pathway has shown efficacy in multiple cancers, but the disease-specific and agent-specific mechanisms of benefit remain unclear. We examined the efficacy and defined the mechanisms of benefit when combining regorafenib (a multikinase antivascular endothelial growth factor receptor inhibitor) with PD1 blockade in murine hepatocellular carcinoma (HCC) models. We used orthotopic models of HCC in mice with liver damage to test the effects of regorafenib—dosed orally at 5, 10 or 20 mg/kg daily—combined with anti-PD1 antibodies (10 mg/kg intraperitoneally thrice weekly). We evaluated the effects of therapy on tumor vasculature and immune microenvironment using immunofluorescence, flow cytometry, RNA-sequencing, ELISA and pharmacokinetic harmacodynamic studies in mice and in tissue and blood s les from patients with cancer. Regorafenib/anti-PD1 combination therapy increased survival compared with regofarenib or anti-PD1 alone in a regorafenib dose-dependent manner. Combination therapy increased regorafenib uptake into the tumor tissues by normalizing the HCC vasculature and increasing CD8 T-cell infiltration and activation at an intermediate regorafenib dose. The efficacy of regorafenib/anti-PD1 therapy was compromised in mice lacking functional T cells ( Rag1 -deficient mice). Regorafenib treatment increased the transcription and protein expression of CXCL10—a ligand for CXCR3 expressed on tumor-infiltrating lymphocytes—in murine HCC and in blood of patients with HCC. Using Cxcr3 -deficient mice, we demonstrate that CXCR3 mediated the increased intratumoral CD8 T-cell infiltration and the added survival benefit when regorafenib was combined with anti-PD1 therapy. Judicious regorafenib/anti-PD1 combination therapy can inhibit tumor growth and increase survival by normalizing tumor vasculature and increasing intratumoral CXCR3+CD8 T-cell infiltration through elevated CXCL10 expression in HCC cells.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 14-10-2019
DOI: 10.1002/HEP.30889
Abstract: Activation of the antitumor immune response using programmed death receptor‐1 (PD‐1) blockade showed benefit only in a fraction of patients with hepatocellular carcinoma (HCC). Combining PD‐1 blockade with antiangiogenesis has shown promise in substantially increasing the fraction of patients with HCC who respond to treatment, but the mechanism of this interaction is unknown. We recapitulated these clinical outcomes using orthotopic—grafted or induced—murine models of HCC. Specific blockade of vascular endothelial receptor 2 (VEGFR‐2) using a murine antibody significantly delayed primary tumor growth but failed to prolong survival, while anti‐PD‐1 antibody treatment alone conferred a minor survival advantage in one model. However, dual anti‐PD‐1/VEGFR‐2 therapy significantly inhibited primary tumor growth and doubled survival in both models. Combination therapy reprogrammed the immune microenvironment by increasing cluster of differentiation 8–positive (CD8 + ) cytotoxic T cell infiltration and activation, shifting the M1/M2 ratio of tumor‐associated macrophages and reducing T regulatory cell (Treg) and chemokine (C‐C motif) receptor 2–positive monocyte infiltration in HCC tissue. In these models, VEGFR‐2 was selectively expressed in tumor endothelial cells. Using spheroid cultures of HCC tissue, we found that PD‐ligand 1 expression in HCC cells was induced in a paracrine manner upon anti‐VEGFR‐2 blockade in endothelial cells in part through interferon‐gamma expression. Moreover, we found that VEGFR‐2 blockade increased PD‐1 expression in tumor‐infiltrating CD4 + cells. We also found that under anti‐PD‐1 therapy, CD4 + cells promote normalized vessel formation in the face of antiangiogenic therapy with anti‐VEGFR‐2 antibody. We show that dual anti‐PD‐1/VEGFR‐2 therapy has a durable vessel fortification effect in HCC and can overcome treatment resistance to either treatment alone and increase overall survival in both anti‐PD‐1 therapy–resistant and anti‐PD‐1 therapy–responsive HCC models.
Publisher: American Association for Cancer Research (AACR)
Date: 2019
DOI: 10.1158/1078-0432.CCR-18-0847
Abstract: Sorafenib is a standard first-line treatment for advanced hepatocellular carcinoma (HCC). The phase III SHARP trial showed a median time-to-progression (mTTP) of 5.5 months, overall response rate (ORR) of 2%, and median overall survival (mOS) of 10.7 months with sorafenib. FOLFOX4 has shown modest activity in advanced HCC. We evaluated the combination of sorafenib and modified (m)FOLFOX in a single-arm, multicenter phase II study. The study included Child–Pugh A patients with advanced HCC and no prior systemic therapies. Patients received sorafenib 400 mg twice a day for 2 weeks, followed by concurrent mFOLFOX [5-fluorouracil (5-FU) 1,200 mg/m2/day for 46 hours, leucovorin 200 mg/m2, and oxaliplatin 85 mg/m2 biweekly]. The primary endpoint was mTTP with an alternative hypothesis of 7 months, and secondary endpoints included ORR, mOS, and circulating biomarkers. The study enrolled 40 patients: HCV/EtOH/HBV, 43%/28%/13% Child–Pugh A5, 70%. Notable grade 3/4 adverse events (AE) included AST/ALT elevation (28%/15%), diarrhea (13%), hyperbilirubinemia (10%), hand–foot syndrome (8%), and bleeding (8%). mTTP was 7.7 months [95% confidence interval (CI): 4.4–8.9], ORR 18%, and mOS 15.1 months (7.9–16.9). Sorafenib + mFOLFOX increased plasma PlGF, VEGF-D, sVEGFR1, IL12p70, and CAIX and CD4+ and CD8+ effector T lymphocytes and decreased plasma sVEGFR2 and s-c-KIT and regulatory T cells (Tregs). Shorter TTP was associated with high baseline sVEGFR1. Shorter TTP and OS were associated with increases in Tregs and CD56Dim natural killer (NK) cells after sorafenib alone and plasma sMET after combination treatment (all P & 0.05). Sorafenib + mFOLFOX met the prespecified endpoint with encouraging efficacy but moderate hepatotoxicity. Thus, this regimen may be effective in select patients with adequate liver reserve. Biomarker evaluations suggested a correlation between time-to-progression (TTP) and angiogenic biomarkers and circulating Tregs.
Publisher: BMJ
Date: 11-01-2021
DOI: 10.1136/GUTJNL-2020-322493
Abstract: Intrahepatic cholangiocarcinoma (ICC)—a rare liver malignancy with limited therapeutic options—is characterised by aggressive progression, desmoplasia and vascular abnormalities. The aim of this study was to determine the role of placental growth factor (PlGF) in ICC progression. We evaluated the expression of PlGF in specimens from ICC patients and assessed the therapeutic effect of genetic or pharmacologic inhibition of PlGF in orthotopically grafted ICC mouse models. We evaluated the impact of PlGF stimulation or blockade in ICC cells and cancer-associated fibroblasts (CAFs) using in vitro 3-D coculture systems. PlGF levels were elevated in human ICC stromal cells and circulating blood plasma and were associated with disease progression. Single-cell RNA sequencing showed that the major impact of PlGF blockade in mice was enrichment of quiescent CAFs, characterised by high gene transcription levels related to the Akt pathway, glycolysis and hypoxia signalling. PlGF blockade suppressed Akt phosphorylation and myofibroblast activation in ICC-derived CAFs. PlGF blockade also reduced desmoplasia and tissue stiffness, which resulted in reopening of collapsed tumour vessels and improved blood perfusion, while reducing ICC cell invasion. Moreover, PlGF blockade enhanced the efficacy of standard chemotherapy in mice-bearing ICC. Conclusion PlGF blockade leads to a reduction in intratumorous hypoxia and metastatic dissemination, enhanced chemotherapy sensitivity and increased survival in mice-bearing aggressive ICC.
No related grants have been discovered for Kohei Shigeta.