Interferon-β lipofection I. Increased efficacy of chemotherapeutic drugs on human tumor cells derived monolayers and spheroids

Abstract

We evaluated the effect of hIFNb gene transfer alone or in combination with different antineoplastic drugs commonly used in cancer treatment. Five human tumor-derived cell lines were cultured as monolayers and spheroids. Four cell lines (Ewing sarcomas EW7 and COH, melanoma M8 and mammary carcinoma MCF-7) were sensitive to hIFNb gene lipofection. Although this effect appeared in both culture configurations, spheroids showed a relative multicellular resistance (insensitive colon carcinoma HT-29 excluded). EW7 and M8 hIFNb-expressing cells were exposed to different concentrations of bleomycin, bortezomib, carboplatin, doxorubicin, etoposide, methotrexate, paclitaxel and vincristine in both configuration models. In chemotherapy-sensitive EW7 monolayers, the combination of hIFNb gene and antineoplastic drugs displayed only additive or counteractive (methotrexate) effects, suggesting that cytotoxic mechanisms triggered by hIFNb gene lipofection could be saturating the signaling pathways. Conversely, in chemotherapy-resistant EW7 spheroids or M8 cells, the combination of hIFNb with drugs that mainly operate at the genotoxic level (doxorubicin, methotrexate and paclitaxel) presented only additive effects. However, drugs that also increase pro-oxidant species can complement the antitumor efficacy of the hIFNb gene and clearly caused potentiated effects (bleomycin, bortezomib, carboplatin, etoposide and vincristine). The great bystander effect induced by hIFNb gene lipofection could be among the main causes of its effectiveness, because only 1 or 2% of EW7 or M8 hIFNb-expressing cells killed more than 60 or 80% of cell population, respectively.

Immunomodulatory and antitumor effects of type I interferons and their application in cancer therapy

“…Many vectors have been employed for the transfer of type I IFN genes, including for modification of tumor cells or DCs (Table 1 ). Among these vectors, adenovirus, AAV and, more recently, non-viral liposome mediated gene transfer have been used in both basic and clinical research protocols [ 306 – 311 ]. Specifically in the case of IFN-α gene transfer, adenovirus is one of the most commonly employed vectors for in situ treatment models, yet lentivirus is better suited for ex vivo creation of IFN-α secreting cells.…”

Cytokine-Enhanced Vaccine and Interferon-β plus Suicide Gene Therapy as Surgery Adjuvant Treatments for Spontaneous Canine Melanoma

“…Escherichia coli b-galactosidase (bgal: psCMVb), herpes simplex thymidine kinase (psCMVtk), canine interferon-b (psCMVcIFNb), human interleukin-2 (psCMVhIL2), and hGM-CSF (psCMVhGM-CSF) genes were subcloned, amplified, purified, and diluted to a final concentration of 2.0 mg/ml in sterile PBS as described. 8,14 Liposomes preparation and in vivo local lipofection Liposomes for in vitro experiments 12 and liposomes for in vivo injection 8 were made as previously reported. The latest ones were composed of equimolar amounts of 1,2-dimyristyl oxypropyl-3-dimethyl-hydroxyethylammonium bromide (DMRIE) and 1,2-dioleoyl-sn-glycero-3-phosphatidyl ethanolamine (DOPE).…”

“…12 Regardless the chosen approach, the presence of local disease substantially shortened patients' median overall survival. 8,11,13 In a different background, local expression of interferon-b induced direct tumor cells cytotoxicity both in vitro 14 and in vivo. 15,16 In canine soft tissue sarcoma-and osteosarcoma-bearing patients, we successfully applied a treatment that combined the local antiproliferative effects of interferon-b and HSVtk suicide gene therapy with the systemic effects triggered by a subcutaneous vaccine composed of formolized tumor extracts and irradiated xenogeneic cells genetically modified to slowly release human interleukin-2 (hIL2) and human granulocytemacrophage colony-stimulating factor (hGM-CSF).…”

3D tissue-engineered model of Ewing's sarcoma

“…In support of this hypothesis, the proteomic signature of human tumor spheroids and 3D scaffold models can be readily distinguished from equivalent cells maintained in monolayer culture. This appears to hold true for ES as well, as cells grown within spheroids or 3D scaffolds (natural and synthetic) more closely approximate the protein expression pattern of human tumors than do cell monolayers cells [53, 54, 80, 86, 90]. …”

“…As such, ES spheroids have been used extensively to judge the effectiveness of chemotherapeutic and biologically targeted drugs (Figure 3) [53, 67, 80, 86, 87], to study the impact of cell signaling pathways that regulate ES cell proliferation [53, 80, 88], to investigate the effects of tumor architecture upon immune cell function, and to identify suitable antigens for immunotherapeutic strategies [89, 90]. ES MCTS have also proven useful for modeling micrometastatic disease, contributed to our understanding of anoikis (a form of cell death that results from lost ECM contact) [53, 88], and served as a platform to evaluate heterotypic interactions between tumor cells and vascular progenitor cells responsible for angiogenesis [77].…”