Laura Masuelli

In Vitro and in Vivo Antitumoral Effects of Combinations of Polyphenols, or Polyphenols and Anticancer Drugs: Perspectives on Cancer Treatment

Carcinogenesis is a multistep process triggered by genetic alterations that activate different signal transduction pathways and cause the progressive transformation of a normal cell into a cancer cell. Polyphenols, compounds ubiquitously expressed in plants, have anti-inflammatory, antimicrobial, antiviral, anticancer, and immunomodulatory properties, all of which are beneficial to human health. Due to their ability to modulate the activity of multiple targets involved in carcinogenesis through direct interaction or modulation of gene expression, polyphenols can be employed to inhibit the growth of cancer cells. However, the main problem related to the use of polyphenols as anticancer agents is their poor bioavailability, which might hinder the in vivo effects of the single compound. In fact, polyphenols have a poor absorption and biodistribution, but also a fast metabolism and excretion in the human body. The poor bioavailability of a polyphenol will affect the effective dose delivered to cancer cells. One way to counteract this drawback could be combination treatment with different polyphenols or with polyphenols and other anti-cancer drugs, which can lead to more effective antitumor effects than treatment using only one of the compounds. This report reviews current knowledge on the anticancer effects of combinations of polyphenols or polyphenols and anticancer drugs, with a focus on their ability to modulate multiple signaling transduction pathways involved in cancer.

Dietary Flavonoids: Molecular Mechanisms of Action as Anti- Inflammatory Agents

Flavonoids are a large group of polyphenolic compounds, which are ubiquitously expressed in plants. They are grouped according to their chemical structure and function into flavonols, flavones, flavan-3-ols, anthocyanins, flavanones and isoflavones. Many of flavonoids are found in fruits, vegetables and beverages. Flavonoids have been demonstrated to have advantageous effects on human health because their anti-allergic, anti-inflammatory, anti-platelet aggregation, anti-tumor and anti-oxidant behavior. This report reviews the current knowledge on the molecular mechanisms of action of flavonoids as anti-inflammatory agents and also discusses the relevant patents.

The contribution of oxidative stress in apoptosis of human-cultured astroglial cells induced by supernatants of HIV-1-infected macrophages

Apoptosis of neurons and astrocytes has been found in patientsundergoing AIDS dementia complex. We demonstrated that supernatantsfrom human primary macrophages (M/M) infected by HIV‐1 lead humanastroglial cells to oxidative stress, as shown by elevated levels ofmalondialdehyde, and then to apoptosis. Electron microscopy ofastrocytes shortly incubated with HIV‐1‐infected M/M supernatantsshowed apoptotic blebbing, cytoplasmic loss, and chromatincondensation. Apoptosis was antagonized by pretreating astrocytes withthe nonpeptidic superoxide dismutase (SOD) mimetic M40401 but notwith anti‐HIV‐1 compounds, thus showing that apoptosis of astrocytesdriven by HIV‐1‐infected M/M supernatants is mainly mediated byabnormal production of superoxide anions without relationship to HIV‐1replication in such cells. Overall results support the role ofoxidative stress mediated by HIV‐1‐infected M/M as one of the leadingcauses of neurodegeneration in patients with HIV‐1 and suggest the useof nonpeptidic SOD mimetics to counteract HIV‐1‐related neurologicaldisorders.

Caveolin‐1 overexpression is associated with simultaneous abnormal expression of the E‐cadherin/α–β catenins complex and multiple erbb receptors and with lymph nodes metastasis in head and neck squamous cell carcinomas

The presence of lymph node metastases is one of the most important prognostic indicators in head and neck squamous cell carcinomas (HNSCCs). An alteration of the E‐cadherin–catenins complex and EGFR is essential for the invasiveness of cancer cells. Caveolin‐1, the major structural protein of the caveolae, represents a scaffolding molecule for several signaling proteins including EGFR. Although caveolin‐1 has been shown to play a role in inducing the invasive phenotype of cancer cells, its role appears to be cell‐type specific and for some tumors it has not been defined yet. In this study we used 57 HNSCC specimens to investigate whether the abnormal expression of caveolin‐1 was associated with the derangement of the E‐cadherin–catenins complex and with the overexpression of ErbB receptors. We demonstrate that in HNSCCs caveolin‐1 overexpression is associated with the simultaneous abnormal expression of at least one member of the E‐cadherin/α–β catenins complex and multiple ErbB receptors as well as with lymph node metastases. We also demonstrate that chronic stimulation of a human hypopharyngeal carcinoma cell line (FaDu) with EGF induced the internalization of β‐catenin and caveolin‐1 and their co‐localization with EGFR. Moreover, EGF treatment induced an increased physical interaction between EGFR/β‐catenin/caveolin‐1 and between E‐cadherin/β‐catenin/caveolin‐1. These molecular events were associated with an increased directional motility of FaDu cells in vitro. These findings may provide new insight into the biology of HNSCC progression and help to identify subgroups of primary HNSCCs with a more aggressive behavior. J. Cell. Physiol. 227: 3344–3353, 2012.

Carcinoembryonic antigen (CEA)-based cancer vaccines: recent patents and antitumor effects from experimental models to clinical trials.

Carcinoembryonic antigen (CEA), a glycosylated protein of MW 180 kDa, is overexpressed in a wide range of human carcinomas, including colorectal, gastric, pancreatic, non-small cell lung and breast carcinomas. Accordingly, CEA is one of several oncofetal antigens that may serve as a target for active anti-cancer specific immunotherapy. Experimental results obtained by employing animal models have supported the design of clinical trials using a CEA-based vaccine for the treatment of different types of human cancers. This review reports findings from experimental models and clinical evidence on the use of a CEA-based vaccine for the treatment of cancer patients. Among the diverse CEA-based cancer vaccines, DCs- and recombinant viruses-based vaccines seem the most valid. However, although vaccination was shown to induce a strong immune response to CEA, resulting in a delay in tumor progression and prolonged survival in some cancer patients, it failed to eradicate the tumor in most cases, owing partly to the negative effect exerted by the tumor microenvironment on immune response. Thus, in order to develop more efficient and effective cancer vaccines, it is necessary to design new clinical trials combining cancer vaccines with chemotherapy, radiotherapy and drugs which target those factors responsible for immunosuppression of immune cells. This review also discusses relevant patents relating to the use of CEA as a cancer vaccine.

The contribution of peroxynitrite generation in HIV replication in human primary macrophages.

BackgroundMonocytes/Macrophages (M/M) play a pivotal role as a source of virus during the whole course of HIV-1 infection. Enhanced oxidative stress is involved in the pathogenesis of HIV-1 infection. HIV-1 regulatory proteins induce a reduction of the expression and the activity of MnSOD, the mitochondrial isoform leading to a sustained generation of superoxide anions and peroxynitrite that represent important mediators of HIV-1 replication in M/M. MnTBAP (Mn(III)tetrakis(4-benzoic acid)porphrin chloride), a synthetic peroxynitrite decomposition catalyst, reduced oxidative stress subsequent to peroxynitrite generation.ResultsVirus production was assessed by p24 ELISA, western blot, and electron microscopy during treatment with MnTBAP. MnTBAP treatment showed a reduction of HIV-1 replication in both acutely and chronically infected M/M: 99% and 90% inhibition of p24 released in supernatants compared to controls, respectively. Maturation of p55 and p24 was strongly inhibited by MnTBAP in both acutely and chronically infected M/M. EC50 and EC90 are 3.7 (± 0.05) μM and 19.5 (± 0.5) μM, in acutely infected M/M; 6.3 (± 0.003) μM and 30 (± 0.6) μM, in chronically infected M/M. In acutely infected peripheral blood limphocytes (PBL), EC50 and EC90 are 7.4 (± 0.06) μM and of 21.3 (± 0.6) μM, respectively. Treatment of acutely-infected M/M with MnTBAP inhibited the elevated levels of malonildialdehyde (MDA) together with the nitrotyrosine staining observed during HIV-1 replication. MnTBAP strongly reduced HIV-1 particles in infected M/M, as shown by electron microscopy. Moreover, in presence of MnTBAP, HIV-1 infectivity was reduced of about 1 log compared to control.ConclusionResults support the role of superoxide anions in HIV-1 replication in M/M and suggest that MnTBAP may counteract HIV-1 replication in combination with other antiretroviral treatments.

Apoptosis and telomeres shortening related to HIV-1 induced oxidative stress in an astrocytoma cell line

BackgroundOxidative stress plays a key role in the neuropathogenesis of Human Immunodeficiency Virus-1 (HIV-1) infection causing apoptosis of astroglia cells and neurons. Recent data have shown that oxidative stress is also responsible for the acceleration of human fibroblast telomere shortening in vitro. In the present study we analyzed the potential relations occurring between free radicals formation and telomere length during HIV-1 mediated astroglial death.ResultsTo this end, U373 human astrocytoma cells have been directly exposed to X4-using HIV-1IIIB strain, for 1, 3 or 5 days and treated (where requested) with N-acetylcysteine (NAC), a cysteine donor involved in the synthesis of glutathione (GSH, a cellular antioxidant) and apoptosis has been evaluated by FACS analysis. Quantitative-FISH (Q-FISH) has been employed for studying the telomere length while intracellular reduced/oxidized glutathione (GSH/GSSG) ratio has been determined by High-Performance Liquid Chromatography (HPLC). Incubation of U373 with HIV-1IIIB led to significant induction of cellular apoptosis that was reduced in the presence of 1 mM NAC. Moreover, NAC improved the GSH/GSSG, a sensitive indicator of oxidative stress, that significantly decreased after HIV-1IIIB exposure in U373. Analysis of telomere length in HIV-1 exposed U373 showed a statistically significant telomere shortening, that was completely reverted in NAC-treated U373.ConclusionOur results support the role of HIV-1-mediated oxidative stress in astrocytic death and the importance of antioxidant compounds in preventing these cellular damages. Moreover, these data indicate that the telomere structure, target for oxidative damage, could be the key sensor of cell apoptosis induced by oxidative stress after HIV infection.

Tendon’s ultrastructure

The structure of a tendon is an important example of complexity of ECM three-dimensional organization. The extracellular matrix (ECM) is a macromolecular network with both structural and regulatory functions. ECM components belong to four major types of macromolecules: the collagens, elastin, proteoglycans, and noncollagenous glycoproteins. Tendons are made by a fibrous, compact connective tissue that connect muscle to bone designed to transmit forces and withstand tension during muscle contraction. Here we show the ultrastructural features of tendons components.

Topical Use of Sucralfate in Epithelial Wound Healing: Clinical Evidence and Molecular Mechanisms of Action

Sucralfate is a basic aluminium salt of sucrose octasulphate which was orally employed for prevention and treatment of several gastrointestinal diseases including gastroesophageal reflux, gastric and duodenal ulcer. Recent studies have employed sucralfate as a topical drug for the healing of several types of epithelial wounds such as ulcers, inflammatory dermatitis, mucositis and burn wounds. Epithelial wound healing is a well orchestrated process involving hemostasis, inflammatory reaction, cell proliferation and tissue remodelling which leads to granulation tissue development and filling of the wound space. This report will review clinical evidences on the use of topical sucralfate for the management of epithelial lesions and deal with the current knowledge on the molecular mechanisms of action of this compound towards the epithelial wound healing process and will also discuss relevant patents.

Type I consensus IFN (IFN-con1) Gene Transfer into KSHV/HHV-8-Infected BCBL-1 Cells Causes Inhibition of Viral Lytic Cycle Activation via Induction of Apoptosis and Abrogates Tumorigenicity in SCID Mice

In this study, we investigated the effects of human type I consensus interferon (IFN-con1) (Amgen) gene transfer into body cavity-based lymphomas (BCBL)-1 cells, which are latently infected with Kaposis sarcoma-associated herpesvirus (KSHV) human herpesvirus-8 (HHV-8). Both the basal and 12-O-tetradecanoyl phorbol-13-acetate (TPA)-stimulated production of KSHV/HHV-8 mature virions was strongly inhibited in genetically modified IFN-producing BCBL-1 cells as compared with parental or control transduced counterparts. A similar inhibition was obtained on treatment of parental BCBL-1 cells with exogenous IFN-con1. The reduction in KSHV/HHV-8 production was associated with a decrease in the basal and TPA-stimulated intracellular amount of the linear form of the viral genome. Interestingly, 25%40% of the IFN-producing BCBL-1 cell population underwent spontaneous apoptosis in vitro. TPA treatment, which did not significantly affect the viability of the parental and control BCBL-1 cells, resulted in the apoptotic death of up to 70% of the IFN-producing cell population. Addition of exogenous IFN-con1 to parental BCBL-1 cells produced similar effects, although less intense. Injection of either parental or control-transduced BCBL-1 cells into SCID mice resulted in progressively growing tumors characterized by an unusually high level of tumor angiogenesis. In contrast, complete tumor regression was observed in all the mice injected either subcutaneously (s.c.) or intraperitoneally (i.p.) with the IFN-producing BCBL-1 cells. These results represent the first evidence that type I IFN can counteract the activation of a productive herpesvirus infection in latently infected tumor cells by the induction of apoptosis, providing an interesting link between the antiviral and antitumor activities of this cytokine. These data suggest the possible advantages of strategies of type I IFN gene transfer (with respect to the use of the exogenous cytokine) for the treatment of patients with some HHV-8-induced malignancies.