Adenoviral-mediated transfer of human wild-type p53, GM-CSF and B7-1 genes results in growth suppression and autologous anti-tumor cytotoxicity of multiple myeloma cells in vitro

Abstract

Multiple myeloma (MM) remains incurable despite the use of high-dose chemotherapy and stem cell transplantation. However, immunotherapy is expected to offer long-term disease control, or even possibly a cure. We have previously demonstrated the suppressive effect of a recombinant adenovirus carrying human wild-type p53, granulocyte-macrophage colony-stimulating factor, and B7-1 genes (Ad-p53/GM-CSF/B7-1) on the growth of laryngeal cancer cells. In the present study, we evaluated the effects of an Ad-p53/GM-CSF/B7-1-modified myeloma cell vaccine strategy aimed to induce apoptosis and to augment the immunogenicity of MM cells. Both MM cell lines and purified primary myeloma cells were infected with Ad-p53/GM-CSF/B7-1. High expression levels of these three genes were confirmed separately by Western blot, enzyme-linked immunosorbent assay (ELISA), and flow cytometry. When wild-type p53, GM-CSF and B7-1 genes were introduced, the growth of MM cells was inhibited via enhanced apoptosis and the immunogenicity of tumor cells was augmented. The combinatorial effect of these three genes on inducing cytotoxic T lymphocytes (CTLs) was more evident than that of p53 individually or any combinations of two (p53 plus GM-CSF or p53 plus B7-1). Furthermore, significant proliferation of autologous peripheral blood lymphocytes (PBLs) and specific cytotoxicity against autologous primary MM cells were induced in vitro. These results suggest that myeloma cell vaccination co-transferred with p53, GM-CSF and B7-1 genes may be a promising immunotherapeutic approach against MM.

Functional characterization of the progestagen‐associated endometrial protein gene in human melanoma

“…Thirty μg of each protein sample from cell lysate or serum‐free culture medium was loaded within an SDS‐PAGE gel followed by electrophoresis. Immunostaining was performed with PAEP (Invitrogen, South San Francisco, CA, USA), Phospho‐eIF2α (Cell signaling, Danvers, MA, USA) or α‐tubulin (Cell signaling) antibody followed by secondary antibody conjugated to horseradish peroxidase as described previously [19]. The blot was visualized with a Fujifilm Luminescent image analyser LAS‐3000 and analysed utilizing Multi‐Gauge V3.1 software (Fujifilm, Valhalla, NY, USA).…”

Gene Therapy for Human Nasopharyngeal Carcinoma by Adenovirus–Mediated Transfer of Human p53, GM-CSF, and B7-1 Genes in a Mouse Xenograft Tumor Model

“…16 Briefly, CNE-1 cells were infected with Ad-GFP, Adp53, Ad-p53/GM-CSF, Ad-p53/B7-1, or Adp53/GM-CSF/B7-1 at a MOI of 100 pfu/cell. Blank culture medium was used for mock infection.…”

“…16,17 In this paper, we evaluated whether the recombinant adenovirus could induce tumor regression and subsequent antitumor response in vitro and in our NPC xenograft models of human immune system established huPBL nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice.…”

Recombinant Modified Vaccinia Virus Ankara (MVA) Expressing Wild-Type Human p53 Induces Specific Antitumor CTL Expansion

“…Although CTLs from human PBMC have been derived against a number of HLA-A2 binding peptides of p53, these CTL are less effective against p53 overexpressing tumor cells. Immunization with whole p53 protein delivered by viral vectors has the advantage of potential stimulation of responses targeting multiple MHC class I and II restricted epitopes (13, 42-43) . In the current study, the diverse nature of an immune response to p53 was confirmed by the demonstration of a higher percentage of IFN-γ ICC positive cells in response to the p53 peptide library compared to both of the well known HLA-A2 epitopes combined (Figure 2(B)).…”