Cancer Immunol Immunother

Purpose Through genome-wide expression profile analysis, hypoxia-inducible protein 2 (HIG2) has previously been identified as an oncoprotein involved in development/progression of renal cell carcinoma (RCC). We subsequently identified a highly immunogenic HLA-A*0201/0206-restricted epitope peptide (HIG2-9-4) corresponding to a part of HIG2 and applied it as a therapeutic vaccine. We conducted a phase I clinical trial using the HIG2-9-4 peptide for patients with advanced RCC. Materials and Methods Nine patients having HLA-A*0201 or HLA-A*0206 with metastatic or unresectable RCC after failure of the cytokine and/or tyrosine kinase inhibitor therapies were enrolled in this study. The patients received subcutaneous administration of the peptide as an emulsion form with Montanide ISA-51 VG once a week in a dose-escalation manner (doses of 0.5, 1.0, or 3.0 mg/body, 3 patients for each dose). The primary endpoint was safety, and the secondary endpoints were immunological and clinical responses. Results Vaccinations with HIG2-9-4 peptide could be well tolerated without any serious systemic adverse events. Peptide-specific cytotoxic T lymphocyte (CTL) responses were detected in eight of the nine patients. Doses of 1.0 or 3.0 mg/body seemed to induce a CTL response better than did a dose of 0.5 mg/body, although the number of patients was too small to draw a firm conclusion. The disease control rate (stable disease for ≥4 months) was 77.8 %, and the median progression-free survival time was 10.3 months. Conclusions HIG2-9-4 peptide vaccine treatment was tolerable and effectively induced peptide-specific CTLs in RCC patients. This novel peptide vaccine therapy for RCC is promising

PREDICTION SYSTEMS FOR BLADDER CANCER THERAPY

The present study established systems to predict the chemo‑sensitivity of muscle invasive bladder cancer (MIBC) for neoadjuvant chemotherapy (NAC) with methotrexate, vinblastine, doxorubicin plus cisplatin (M‑VAC) and carboplatin plus gemcitabine (CaG) by analyzing microarray data. The primary aim of the study was to investigate whether the clinical response would increase by combining these prediction systems. Treatment of each MIBC case was allocated into M‑VAC NAC, CaG NAC, surgery, or radiation therapy groups by their prediction score (PS), which was calculated using the designed chemo‑sensitivity prediction system. The therapeutic effect of the present study was compared with the results of historical controls (n=76 patients) whose treatments were not allocated using the chemo‑sensitivity prediction system. In addition, the overall survival between the predicted to be responder (positive PS) group and predicted to be non‑responder (negative PS) group was investigated in the present study. Of the 33 patients with MIBC, 25 cases were positive PS and 8 were negative PS. Among the 25 positive PS cases, 7 were allocated to receive M‑VAC NAC and 18 were allocated to receive CaG NAC according to the results of the prediction systems. Of the 8 negative PS cases, 3 received CaG NAC, 1 received surgery without NAC and 4 received radiation therapy. The total clinical response to NAC was 88.0% (22/25), which was significantly increased compared with the historical controls [56.6% (43/76) P=0.0041]. Overall survival of the positive PS group in the study was significantly increased compared with the negative PS group (P=0.027). In conclusion, the combination of the two prediction systems may increase the treatment efficacy for patients with MIBC by proposing the optimal NAC regimen. In addition, the positive PS group would have a better prognosis compared with the negative PS group. These results suggest that the two prediction systems may lead to the achievement of ‘precision medicine’

A phospho-switch controls RNF43-mediated degradation of Wnt receptors to suppress tumorigenesis.

Funder: Japan Foundation for Applied Enzymology; doi: https://doi.org/10.13039/100008695Funder: Pancreas Research Foundation of Japan Collaborative Research Project Program of the Medical Institute of Bioregulation, Kyushu University, Japan Joint Research Program of the Institute for Molecular and Cellular Regulation, Gunma University, Japan Grant for Joint Research Project of the Research Institute for Microbial Diseases Osaka UniversityFunder: European Research Council (ERC (639050) and the Interpark Bio-Convergence Center Grant Program.Frequent mutation of the tumour suppressor RNF43 is observed in many cancers, particularly colon malignancies. RNF43, an E3 ubiquitin ligase, negatively regulates Wnt signalling by inducing degradation of the Wnt receptor Frizzled. In this study, we discover that RNF43 activity requires phosphorylation at a triplet of conserved serines. This phospho-regulation of RNF43 is required for zebrafish development and growth of mouse intestinal organoids. Cancer-associated mutations that abrogate RNF43 phosphorylation cooperate with active Ras to promote tumorigenesis by abolishing the inhibitory function of RNF43 in Wnt signalling while maintaining its inhibitory function in p53 signalling. Our data suggest that RNF43 mutations cooperate with KRAS mutations to promote multi-step tumorigenesis via the Wnt-Ras-p53 axis in human colon cancers. Lastly, phosphomimetic substitutions of the serine trio restored the tumour suppressive activity of extracellular oncogenic mutants. Therefore, harnessing phospho-regulation of RNF43 might be a potential therapeutic strategy for tumours with RNF43 mutations

Visualization of Ras-PI3K interaction in the endosome using BiFC

Recent studies indicate the importance of spatiotemporal regulation in the diversity and specificity of intracellular signaling. Here, we show that Ras-PI3K signaling plays an important role in the local regulation of phosphatidylinositol metabolism in the endosome through live-cell imaging by using a bimolecular fluorescence complementation technique, in which molecular interaction is indicated by fluorescence emission. Using several possible combinations of Ras and the Ras-binding domain, we identified an optimal set of probe molecules that yielded the most significant increase in fluorescence intensity between the active and inactive forms of Ras. This combination revealed that, among the Ras effectors tested, phosphatidylinositol 3-kinase (PI3K) was specifically implicated in signaling in the endosome. We also found that full length PI3K was recruited to the endosome in EGF- and Ras-dependent manners, which appears to be essential for the activation of PI3K in this compartment. Taken together, these findings demonstrate that the spatiotemporal regulation of Ras-PI3K signaling may dictate the activation of PI3K and subsequent downstream signaling in the endosome

Attenuation of ligand-induced activation of angiotensin II type 1 receptor signaling by the type 2 receptor via protein kinase C

Angiotensin II (AII) type 2 receptor (AT2R) negatively regulates type 1 receptor (AT1R) signaling. However, the precise molecular mechanism of AT2R-mediated AT1R inhibition remains poorly understood. Here, we characterized the local and functional interaction of AT2R with AT1R. AT2R colocalized and formed a complex with AT1R at the plasma membrane, even in the absence of AII. Upon AII stimulation, the spatial arrangement of the complex was modulated, as confirmed by Forster resonance energy transfer (FRET) analysis, followed by AT2R internalization along with AT1R. AT2R internalization was specifically observed only in the presence of AT1R; AT2R alone could not be internalized. The AT1R-specific inhibitor losartan completely inhibited both the conformational change and the internalization of AT2R with AT1R, whereas the AT2R-specific inhibitor PD123319 partially hindered these phenomena, demonstrating that the activation of both receptors was indispensable for these effects. In addition, treatment with the protein kinase C (PKC) inhibitors inhibited the ligand-dependent accumulation of AT2R but not that of AT1R in the endosomes. A mutation in the putative phosphorylation sites of AT2R also abrogated the co-internalization of ATR2 with AT1R and the inhibitory effect of ATR2 on AT1R. These data suggest that AT2R inhibits ligand-induced AT1R signaling through the PKC-dependent pathway

A Ca2+-dependent signalling circuit regulates influenza A virus internalization and infection

Various viruses enter host cells via endocytosis, but the molecular mechanisms underlying the specific internalization pathways remain unclear. Here we show that influenza A viruses (IAVs) enter cells via redundant pathways of clathrin-mediated and clathrin-independent endocytosis, with intracellular Ca2+ having a central role in regulation of both pathways by activating a signalling axis comprising RhoA, Rho-kinase, phosphatidylinositol 4-phosphate 5-kinase (PIP5K) and phospholipase C (PLC). IAV infection induces oscillations in the cytosolic Ca2+ concentration of host cells, the prevention of which markedly attenuates virus internalization and infection. The small GTPase RhoA is found both to function downstream of the virus-induced Ca2+ response and itself to induce Ca2+ oscillations in a manner dependent on Rho-kinase and subsequent PIP5K-PLC signalling. This signalling circuit regulates both clathrin-mediated and clathrin-independent endocytosis during virus infection and seems to constitute a key mechanism for regulation of IAV internalization and infection

A method for the generation of pseudovirus particles bearing SARS coronavirus spike protein in high yields

The ongoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has threatened human health and the global economy. Development of additional vaccines and therapeutics is urgently required, but such development with live virus must be conducted with biosafety level 3 confinement. Pseudotyped viruses have been widely adopted for studies of virus entry and pharmaceutical development to overcome this restriction. Here we describe a modified protocol to generate vesicular stomatitis virus (VSV) pseudotyped with SARS-CoV or SARSCoV-2 spike protein in high yield. We found that a large proportion of pseudovirions produced with the conventional transient expression system lacked coronavirus spike protein at their surface as a result of inhibition of parental VSV infection by overexpression of this protein. Establishment of stable cell lines with an optimal expression level of coronavirus spike protein allowed the efficient production of progeny pseudoviruses decorated with spike protein. This improved VSV pseudovirus production method should facilitate studies of coronavirus entry and development of antiviral agents

A method for the generation of pseudovirus particles bearing SARS coronavirus spike protein in high yields

The ongoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has threatened human health and the global economy. Development of additional vaccines and therapeutics is urgently required, but such development with live virus must be conducted with biosafety level 3 confinement. Pseudotyped viruses have been widely adopted for studies of virus entry and pharmaceutical development to overcome this restriction. Here we describe a modified protocol to generate vesicular stomatitis virus (VSV) pseudotyped with SARS-CoV or SARS-CoV-2 spike protein in high yield. We found that a large proportion of pseudovirions produced with the conventional transient expression system lacked coronavirus spike protein at their surface as a result of inhibition of parental VSV infection by overexpression of this protein. Establishment of stable cell lines with an optimal expression level of coronavirus spike protein allowed the efficient production of progeny pseudoviruses decorated with spike protein. This improved VSV pseudovirus production method should facilitate studies of coronavirus entry and development of antiviral agents.ISSN:0386-7196ISSN:1347-370