Maria Gabriella Giganti

Intratumoral delivery of recombinant vaccinia virus encoding for ErbB2/Neu inhibits the growth of salivary gland carcinoma cells

BackgroundThe antitumor activity induced by intratumoral vaccination with poxvirus expressing a tumor antigen was shown to be superior to that induced by subcutaneous vaccination. Salivary gland carcinomas overexpress ErbB2. Trastuzumab, a monoclonal antibody to ErbB2, was proposed for salivary gland tumors treatment. We explored the effectiveness of intratumoral vaccination with the recombinant vaccinia virus ErbB2/Neu (rV-neu T) vaccine in hampering the growth of transplanted Neu-overexpressing BALB-neu T salivary gland cancer cells (SALTO) in BALB-neu T mice.MethodsBALB-neu T male mice were subcutaneously injected with SALTO tumor cells and intratumorally vaccinated twice with different doses of either rV-neu T or V-wt (wild-type). Tumors were measured weekly. The presence of anti-ErbB2/Neu antibodies was assayed by ELISA, immunoprecipitation or indirect immunofluorescence. Biological activity of immune sera was investigated by analyzing antibody-dependent cellular cytotoxicity (ADCC), SALTO cells proliferation and apoptosis, ErbB2/Neu receptor down regulation and ERK1/2 phosphorylation. Anti-Neu T cell immunity was investigated by determining the release of IL-2 and IFN-gamma in T cells supernatant. Survival curves were determined using the Kaplan-Meier method and compared using the log-rank test. Differences in tumor volumes, number of apoptotic cells, titer of the serum, percentage of ADCC were evaluated through a two-tailed Student’s t-test.ResultsrV-neu T intratumoral vaccination was able to inhibit the growth of SALTO cancer cells in a dose-dependent manner. The anti-Neu serum titer paralleled in vivo antitumor activity of rV-neu T vaccinated mice. rV-neu T immune serum was able to mediate ADCC, inhibition of SALTO cells proliferation, down regulation of the ErbB2/Neu receptor, inhibition of ERK1/2 phosphorylation and induction of apoptosis, thus suggesting potential mechanisms of in vivo tumor growth interference. In addition, spleen T cells of rV-neu T vaccinated mice released IFN-gamma and IL-2 upon in vitro stimulation with several Neu-specific peptides located in the extracellular domain of Neu sequence.ConclusionsrV-neu T intratumoral vaccination could be employed to induce an efficient antitumor response and reject transplanted salivary gland tumors. Our findings may have important implications for the design of cancer vaccine protocols for the treatment of salivary gland tumors and other accessible tumors using intratumoral injection of recombinant vaccinia virus.

Curcumin blocks autophagy and activates apoptosis of malignant mesothelioma cell lines and increases the survival of mice intraperitoneally transplanted with a malignant mesothelioma cell line

Malignant mesothelioma (MM) is a primary tumor arising from the serous membranes. The resistance of MM patients to conventional therapies, and the poor patients’ survival, encouraged the identification of molecular targets for MM treatment. Curcumin (CUR) is a “multifunctional drug”. We explored the in vitro effects of CUR on cell proliferation, cell cycle regulation, pro-survival signaling pathways, apoptosis, autophagy of human (MM-B1, H-Meso-1, MM-F1), and mouse (#40a) MM cells. In addition, we evaluated the in vivo anti-tumor activities of CUR in C57BL/6 mice intraperitoneally transplanted with #40a cells forming ascites. CUR in vitro inhibited MM cells survival in a dose- and time-dependent manner and increased reactive oxygen species’intracellular production and induced DNA damage. CUR triggered autophagic flux, but the process was then blocked and was coincident with caspase 8 activation which activates apoptosis. CUR-mediated apoptosis was supported by the increase of Bax/Bcl-2 ratio, increase of p53 expression, activation of caspase 9, cleavage of PARP-1, increase of the percentage of cells in the sub G1 phase which was reduced (MM-F1 and #40a) or abolished (MM-B1 and H-Meso-1) after MM cells incubation with the apoptosis inhibitor Z-VAD-FMK. CUR treatment stimulated the phosphorylation of ERK1/2 and p38 MAPK, inhibited that of p54 JNK and AKT, increased c-Jun expression and phosphorylation and prevented NF-κB nuclear translocation. Intraperitoneal administration of CUR increased the median survival of C57BL/6 mice intraperitoneally transplanted with #40a cells and reduced the risk of developing tumors. Our findings may have important implications for the design of MM treatment using CUR.

Effects of Polyphenols on Oxidative Stress-Mediated Injury in Cardiomyocytes

Cardiovascular diseases are the main cause of mortality and morbidity in the world. Hypertension, ischemia/reperfusion, diabetes and anti-cancer drugs contribute to heart failure through oxidative and nitrosative stresses which cause cardiomyocytes nuclear and mitochondrial DNA damage, denaturation of intracellular proteins, lipid peroxidation and inflammation. Oxidative or nitrosative stress-mediated injury lead to cardiomyocytes apoptosis or necrosis. The reactive oxygen (ROS) and nitrogen species (RNS) concentration is dependent on their production and on the expression and activity of anti-oxidant enzymes. Polyphenols are a large group of natural compounds ubiquitously expressed in plants, and epidemiological studies have shown associations between a diet rich in polyphenols and the prevention of various ROS-mediated human diseases. Polyphenols reduce cardiomyocytes damage, necrosis, apoptosis, infarct size and improve cardiac function by decreasing oxidative stress-induced production of ROS or RNS. These effects are achieved by the ability of polyphenols to modulate the expression and activity of anti-oxidant enzymes and several signaling pathways involved in cells survival. This report reviews current knowledge on the potential anti-oxidative effects of polyphenols to control the cardiotoxicity induced by ROS and RNS stress.

The Potential Protective Effects of Polyphenols in Asbestos-Mediated Inflammation and Carcinogenesis of Mesothelium

Malignant Mesothelioma (MM) is a tumor of the serous membranes linked to exposure to asbestos. A chronic inflammatory response orchestrated by mesothelial cells contributes to the development and progression of MM. The evidence that: (a) multiple signaling pathways are aberrantly activated in MM cells; (b) asbestos mediated-chronic inflammation has a key role in MM carcinogenesis; (c) the deregulation of the immune system might favor the development of MM; and (d) a drug might have a better efficacy when injected into a serous cavity thus bypassing biotransformation and reaching an effective dose has prompted investigations to evaluate the effects of polyphenols for the therapy and prevention of MM. Dietary polyphenols are able to inhibit cancer cell growth by targeting multiple signaling pathways, reducing inflammation, and modulating immune response. The ability of polyphenols to modulate the production of pro-inflammatory molecules by targeting signaling pathways or ROS might represent a key mechanism to prevent and/or to contrast the development of MM. In this review, we will report the current knowledge on the ability of polyphenols to modulate the immune system and production of mediators of inflammation, thus revealing an important tool in preventing and/or counteracting the growth of MM.

Patients with Peri-Implantitis, unlike Those with a Healthy Peri-Implant Microenvironment, Display Antibodies to More Than One Heat Shock Protein (HSP 27, HSP 65 and HSP 90) Linear Epitope:

The success of a dental implant treatment requires hard and soft tissue integration and osseointegration, mechanisms that entail a direct anchorage of the implant in the bone without interposition of soft tissue. Peri-implantitis is defined as an inflammatory reaction of the tissues surrounding a functioning dental implant. During inflammation, a high incidence of autoantibodies has been reported. The hypothesis of the present study is that the occurrence of autoantibodies to self-antigens including extracellular matrix (ECM) molecules and heat shock proteins (HSPs) might affect the dental implant outcome. Therefore, we evaluated the occurrence of antibodies to ECM molecules (Collagen (C) I, III, IV, V, fibronectin, laminin) and HSPs (HSP 27, HSP 65, HSP 90) in subjects with a healthy peri-implant microenvironment (n=29) as compared to patients with peri-implantitis (n=13). We also evaluated the HSP 27 expression in gingival fibroblasts grown in an inflammatory microenvironment. Antibodies to conformational ECM epitopes of CI, CIII and laminin were observed both in subjects with healthy peri-implant conditions and peri-implantitis. Antibodies to more than one HSP linear epitope were found in patients with peri-implantitis but not with healthy peri-implant conditions (p=0.024). Gingival fibroblasts grown in an inflammatory microenvironment showed increased HSP 27 cytoplasmic and plasma membrane expression as compared to fibroblasts grown in normal conditions. Immunity to multiple linear HSPs epitopes in patients with peri-implantitis and not in patients with a healthy peri-implant microenvironment might be relevant for monitoring the implant outcome and help to understand the role of subsets of autoantibodies in implant osseointegration.

Poxvirus-Based Vaccines for Cancer Immunotherapy: New Insights from Combined Cytokines/Co-Stimulatory Molecules Delivery and “Uncommon” Strains

Poxvirus-based vaccines have a long record of efficacy as both anti-tumour agents and vectors for gene therapy in different human tumour models. Interestingly, several studies of these vaccines have now entered the clinical evaluation phase for safety and effectiveness. A desirable outcome of antigen specific cancer immunotherapy is the disruption of host self-tolerance against endogenous tumour-associated antigens (TAAs). Nonetheless, recent studies have found reductions in vaccine efficacy due to host anti-vaccine immune reactions. Thus, newer approaches bringing together poxvirus-based vaccination and immunostimulation are being developed, and new poxvirus strains are being examined in tumour therapy studies. Our review summarizes the current knowledge on the efficacy of poxvirus-based vaccination on human tumours, with a particular focus on approaches aimed at increasing innate and specific immune responses. Special attention will be devoted to the new poxvirus strains that are currently under consideration for tumour therapy; the current knowledge on clinical trials and outcomes will also be reviewed.

In Vitro and In Vivo Anti-tumoral Effects of the Flavonoid Apigenin in Malignant Mesothelioma

Malignant mesothelioma (MM) is a tumor arising from mesothelium. MM patients’ survival is poor. The polyphenol 4′,5,7,-trihydroxyflavone Apigenin (API) is a “multifunctional drug”. Several studies have demonstrated API anti-tumoral effects. However, little is known on the in vitro and in vivo anti-tumoral effects of API in MM. Thus, we analyzed the in vitro effects of API on cell proliferation, cell cycle regulation, pro-survival signaling pathways, apoptosis, and autophagy of human and mouse MM cells. We evaluated the in vivo anti-tumor activities of API in mice transplanted with MM #40a cells forming ascites. API inhibited in vitro MM cells survival, increased reactive oxygen species intracellular production and induced DNA damage. API activated apoptosis but not autophagy. API-induced apoptosis was sustained by the increase of Bax/Bcl-2 ratio, increase of p53 expression, activation of both caspase 9 and caspase 8, cleavage of PARP-1, and increase of the percentage of cells in subG1 phase. API treatment affected the phosphorylation of ERK1/2, JNK and p38 MAPKs in a cell-type specific manner, inhibited AKT phosphorylation, decreased c-Jun expression and phosphorylation, and inhibited NF-κB nuclear translocation. Intraperitoneal administration of API increased the median survival of C57BL/6 mice intraperitoneally transplanted with #40a cells and reduced the risk of tumor growth. Our findings may have important implications for the design of MM treatment using API.

(±)-Gossypol induces apoptosis and autophagy in head and neck carcinoma cell lines and inhibits the growth of transplanted salivary gland cancer cells in BALB/c mice

Abstract Racemic Gossypol [(±)-GOS], composed of both (−)-GOS and (+)-GOS, is a small BH3-mimetic polyphenol derived from cotton seeds. (±)-GOS has been employed and well tolerated by cancer patients. Head and neck carcinoma (HNC) represents one of the most fatal cancers worldwide, and a significant proportion of HNC expresses high levels of antiapoptotic Bcl-2 proteins. In this study, we demonstrate that (±)-GOS inhibits cell proliferation and induces apoptosis and autophagy of human pharynx, tongue, and salivary gland cancer cell lines and of mouse salivary gland cancer cells (SALTO). (±)-GOS was able to: (a) decrease the ErbB2 protein expression; (b) inhibit the phosphorylation of ERK1/2 and AKT; (c) stimulate p38 and JNK1/2 protein phosphorylation. (±)-GOS administration was safe in BALB/c mice and it reduced the growth of transplanted SALTO cells in vivo and prolonged mice median survival. Our results suggest the potential role of (±)-GOS as an antitumor agent in HNC patients.

Electrochemically Reduced Water Delays Mammary Tumors Growth in Mice and Inhibits Breast Cancer Cells Survival In Vitro

Electrochemical reduced water (ERW) has been proposed to have beneficial effects on human health due to its rich content of H2 and the presence of platinum nanoparticles with antioxidant effects. Many studies have demonstrated that ERW scavenging properties are able to reduce the damage caused by oxidative stress in different experimental models. Although few in vivo studies have been reported, it has been demonstrated that ERW may display anticancer effects by induction of tumor cells apoptosis and reduction of both angiogenesis and inflammation. In this study, we show that ERW treatment of MCF-7, MDA-MB-453, and mouse (TUBO) breast cancer cells inhibited cell survival in a time-dependent fashion. ERW decreased ErbB2/neu expression and impaired pERK1/ERK2 and AKT phosphorylation in breast cancer cells. In addition, ERW treatment induced apoptosis of breast cancer cell lines independently of the status of p53 and ER and PR receptors. Our in vivo results showed that ERW treatment of transgenic BALB-neuT mice delayed the development of mammary tumors compared to the control. In addition, ERW induced a significant prolongation of tumor-free survival and a reduction in tumor multiplicity. Overall, these results suggest a potential beneficial role of ERW in inhibiting cancer cells growth.