Signaling pathways influencing tumor microenvironment and their exploitation for targeted drug delivery

In the recent years, the "tumor microenvironment" has been receiving growing attention due to its involvement in neoplastic transformation, tumor growth, invasion, and protection of tumor cells from host immune response. All these events are facilitated by chemical signals produced by the tumor as well as the surrounding stromal cells. This review is divided into two main parts in which the first part discusses the receptor tyrosine kinase (RTK)-mediated growth factor signaling, steroid hormone (SH) signaling, ancient signaling pathways, and other molecules that are involved in tumorigenesis and how they interact with each other to create a complex tumor microenvironment. In the second part, we bring together the recent nanocarrier-mediated drug delivery approaches to target the signaling pathways/molecules present in the tumor microenvironment.Foundation for Science and Technology (FCT) [(SFRH/BPD/89493/2012]; FCT [SFRH/BD/72809/2010]; Portuguese Government; FCT national funds (PIDDAC) [PTDC/AGR-GPL/119211/2010, PEst-C/AGR/UI4033/2011]; European Fund for Regional Development (FEDER) through COMPETE Operational Programme Competitive Factors (POFC)info:eu-repo/semantics/publishedVersio

Development of novel nanomedicines for the treatment of non-small cell lung cancer

Lung cancer stands as one of the deadliest diseases, responsible for the most cancer related deaths worldwide. The UK 5-year survival rate of non-small-cell lung cancer (NSCLC), the predominant subtype of lung cancer, stands at 9.5%, highlighting an unmet need for therapeutic intervention. A key issue is the lack of efficacy current chemotherapy regimens have in the clinic. These therapies often suffer from poor tumour targeting, resulting in dissemination throughout the body and inadequate concentrations in the tumour. This causes deleterious side effects contributing to a reduced patient quality of life and ultimately survival. Nanomedicine may serve to overcome the current therapeutic hurdles in treating NSCLC; the use of nanoparticles (NPs) for the delivery of drugs can improve drug targeting to tumours, increasing efficacy and attenuating off-target side effects. NPs can be used to deliver multiple drugs and be made from varying materials such as gold (AuNPs) or polymers. Furthermore, the discovery of oncogenic mutations in genes like EGFR present druggable targets in patients harbouring the appropriate mutations. This can also be taken advantage of using NPs to more directly target tumours and increase therapeutic response. Therefore, the aim of this thesis was to develop novel NP formulations comprised of a chemically modified variant of the tyrosine kinase inhibitor afatinib and gold (Afb-AuNPs) or in combination with vinorelbine as a polymeric dual chemotherapy formulation (Dual-NPs). Drug-bearing NPs were synthesised using a combination of organic chemistry and hydrophobic ion pairing, after which the NPs were extensively characterised to discern their physicochemical properties. We then sought to investigate the in vitro efficacy of NPs. Cell viability studies revealed Afb-AuNPs and Dual-NPs were significantly cytotoxic to various NSCLC cell lines and comparatively nontoxic to noncancerous cells. Moreover, NP formulations were found to significantly inhibit proliferation of A549, H226 and PC-9 cells 3 compared to clinical formulations as determined by electric cell-substrate impedance sensing. The mechanism of uptake in cancer cells was elucidated using fluorescent NPs as a model system and quantified using confocal microscopy. Finally, the in vivo activity of biocompatibility of Dual-NPs was investigated in a physiologically relevant murine model of NSCLC. Taken together, these results highlight the therapeutic potential for NP formulations of chemotherapy.Open Acces

Targeted nanoparticle formulation for a poorly water soluble Gemcitabine derivative and its in vivo and in vitro anti-tumor activity

textCancer is a collection of over one hundred different types of diseases and is responsible for the leading cause of death in the United States. More strikingly, cancer mortality rates have remained relatively unchanged for the past several decades, indicating significant clinical demand for improved cancer therapy. Gemcitabine, known clinically as Gemzar®, is used to treat a variety of human cancers, however, clinical efficacy is modest due to it’s brief blood circulation, rapid clearance, manifestation of tumor-drug resistance, and lack of drug specificity. This thesis sought to develop a solid lipid nanoparticle-based platform to passively and actively target a gemcitabine lipophilic derivative, 4-(N)-stearoyl gemcitabine, into tumor cells over-expressing epidermal growth factor receptor (EGFR) after intravenous injection. Considering gemcitabine is hydrophilic and the core of the nanoparticle is solid (hydrophobic), we lipophilized gemcitabine by conjugating a stearoyl group to its N-terminus to form 4-(N)-stearoyl gemcitabine. Second, we incorporated stearoyl gemcitabine into lecithin-based nanoparticles. The nanoparticle formulation was prepared from lecithin/glyceryl monostearate-in-water emulsions. Third, we grafted the gemcitabine nanoparticles with polyethylene glycol chains with reactive end groups that are capable of conjugating with a targeting moiety on the surface to actively target tumors that over-express EGFR. Taken together, the overall objective of the research presented in this thesis is to develop, characterize, and evaluate the anti-tumor performance in vitro as well as in mice against both human and mouse tumor models.Pharmac

チタニアナノ粒子の細胞応答への影響

早大学位記番号:新7860早稲田大

Onco-Receptors Targeting in Lung Cancer via Application of Surface-Modified and Hybrid Nanoparticles: A Cross-Disciplinary Review

Lung cancer is among the most prevalent and leading causes of death worldwide. The major reason for high mortality is the late diagnosis of the disease, and in most cases, lung cancer is diagnosed at fourth stage in which the cancer has metastasized to almost all vital organs. The other reason for higher mortality is the uptake of the chemotherapeutic agents by the healthy cells, which in turn increases the chances of cytotoxicity to the healthy body cells. The complex pathophysiology of lung cancer provides various pathways to target the cancerous cells. In this regard, upregulated onco-receptors on the cell surface of tumor including epidermal growth factor receptor (EGFR), integrins, transferrin receptor (TFR), folate receptor (FR), cluster of differentiation 44 (CD44) receptor, etc. could be exploited for the inhibition of pathways and tumor-specific drug targeting. Further, cancer borne immunological targets like T-lymphocytes, myeloid-derived suppressor cells (MDSCs), tumor-associated macrophages (TAMs), and dendritic cells could serve as a target site to modulate tumor activity through targeting various surface-expressed receptors or interfering with immune cell-specific pathways. Hence, novel approaches are required for both the diagnosis and treatment of lung cancers. In this context, several researchers have employed various targeted delivery approaches to overcome the problems allied with the conventional diagnosis of and therapy methods used against lung cancer. Nanoparticles are cell nonspecific in biological systems, and may cause unwanted deleterious effects in the body. Therefore, nanodrug delivery systems (NDDSs) need further advancement to overcome the problem of toxicity in the treatment of lung cancer. Moreover, the route of nanomedicines’ delivery to lungs plays a vital role in localizing the drug concentration to target the lung cancer. Surface-modified nanoparticles and hybrid nanoparticles have a wide range of applications in the field of theranostics. This cross-disciplinary review summarizes the current knowledge of the pathways implicated in the different classes of lung cancer with an emphasis on the clinical implications of the increasing number of actionable molecular targets. Furthermore, it focuses specifically on the significance and emerging role of surface functionalized and hybrid nanomaterials as drug delivery systems through citing recent examples targeted at lung cancer treatment.The APC was funded through PHOTO-EMULSION project. Financing entity: European Union H2020-MSCA-ITN-2017

Developing actively targeted nanoparticles to fight cancer: Focus on italian research

Active targeting is a valuable and promising approach with which to enhance the therapeutic efficacy of nanodelivery systems, and the development of tumor-targeted nanoparticles has therefore attracted much research attention. In this field, the research carried out in Italian Pharmaceutical Technology academic groups has been focused on the development of actively targeted nanosystems using a multidisciplinary approach. To highlight these efforts, this review reports a thorough description of the last 10 years of Italian research results on the development of actively targeted nanoparticles to direct drugs towards different receptors that are overexpressed on cancer cells or in the tumor microenvironment. In particular, the review discusses polymeric nanocarriers, liposomes, lipoplexes, niosomes, solid lipid nanoparticles, squalene nanoassemblies and nanobubbles. For each nanocarrier, the main ligands, conjugation strategies and target receptors are described. The literature indicates that polymeric nanoparticles and liposomes stand out as key tools for improving specific drug delivery to the site of action. In addition, solid lipid nanoparticles, squalene nanoparticles and nanobubbles have also been successfully proposed. Taken together, these strategies all offer many platforms for the design of nanocarriers that are suitable for future clinical translation

Role of the Hyaluronan Receptor, Stabilin-2/HARE, in Health and Disease

Stabilin-2/HARE is the primary clearance receptor for circulating hyaluronan (HA), a polysaccharide found in the extracellular matrix (ECM) of metazoans. HA has many biological functions including joint lubrication, ocular turgor pressure, skin elasticity and hydration, cell motility, and intercellular signaling, among many others. The regulatory system for HA content in the tissues, lymphatics, and circulatory systems is due, in part, to Stabilin-2/HARE. The activity of this receptor was discovered about 40 years ago (early 1980s), cloned in the mid-1990s, and has been characterized since then. Here, we discuss the overall domain organization of this receptor and how it correlates to ligand binding, cellular signaling, and its role in known physiological disorders such as cancer

Targeted therapies in breast cancer

Trabalho Final de Mestrado Integrado, Ciências Farmacêuticas, Universidade de Lisboa, Faculdade de Farmácia, 2017Breast cancer is a disease responsible for millions of deaths annually. It’s a very heterogenous disease due to the different mutations on each case. Breast cancer doesn’t have existing cure, and it’s currently approached through therapeutic schemes involving radiotherapy, chemotherapy and surgical procedure. Both radiotherapy as chemotherapy act adjunctly allowing further removal through lumpectomy or mastectomy. Current chemotherapy can’t distinguish between healthy and malignant cells, causing patient suffering through adverse effects. So, there’s a demand to find out novel therapies more efficient e selective. However, many researchers claim to found novel selective approaches, that ultimately aren’t. Potentially new drugs on research will be analysed, and an efficient and viable drug design is proposed to cure breast cancer.O cancro da mama é uma doença responsável por milhões de mortes anualmente. É uma doença muito heterogenia devido às diferentes mutações existentes em cada caso. O cancro da mama não tem uma cura existente, ele é tratado através de uma série de esquemas terapêuticos que envolve radioterapia, quimioterapia e cirurgia. Tanto a radio como a quimioterapia são unicamente adjuvantes de modo a permitir a remoção do cancro através de uma lumpectomia ou mastectomia. A quimioterapia corrente usada não consegue distinguir células malignas de células saudáveis e isso remete para reações adversas sentidas pelo doente que tornam a terapia dolorosa. Existe, portanto, uma demanda de novas opções terapêuticas mais eficazes e seletivas. Contundo, muito investigadores referem descobrir novas terapêuticas seletivas que acabam por não o ser. Faz-se uma crítica a potenciais novos fármacos em investigação, mas também se propõe a síntese de fármacos mais eficazes e viáveis na cura do cancro da mama

Understanding the Mechanism of Hard Metal (WC-Co) Toxicity: In vitro Studies and In vivo Exploration

Hard metals, such as tungsten carbide cobalt (WC-Co), are frequently used for a number of industrial applications such as surface coatings for heavy machinery and tools. In particular, WC-Co coatings are prevalent in mining and drilling applications where extensive, repetitive use of these tools causes wear over time. In enclosed environments, WC-Co wear particles become airborne and present an occupational inhalation hazard. It is known that inhalation of WC-Co dusts , composed of nano- and micro-sized WC-Co particles, contributes to the development of hard metal lung disease and increased risk for lung cancer; however, the relationship between acute WC-Co toxicity and disease progression remains poorly understood. To address this gap in knowledge, we systematically evaluated nano-WC-Co particle toxicity using a combination of in vitro and in vivo models. In Aim 1, we determined the toxicity of nano-WC-Co particles in BEAS-2B lung epithelial cells over concentrations ranging 0.1 to 1000 mug/mL and exposure periods from 0.5 to 48 hr. Our MTT-based cell viability assay indicated that nano-WC-Co exhibits greater toxicity than micro-WC-Co at concentrations ≥ 10 mug/mL. We also found that nano-WC-Co exposure induces oxidative stress at the highest particle concentration tested (1000 mug/mL) using a fluorescence-based (DCF/DHE) assay and that WC-Co particle exposure induced cellular apoptosis, marked by increased annexin-V staining in our flow cytometry apoptosis assay. The potential for nano-WC-Co particle internalization was also investigated using transmission electron microscopy (TEM) and confirmed that nano-WC-Co particles are capable of being internalized by BEAS-2B cells. In Aim 2, we determined the inflammatory response toward nano-WC-Co particles in a co-culture model of BEAS-2B cells and macrophages, to more closely represent the dynamic tissue environment of the lung. The results of our viability assay indicated that macrophages attenuated the toxicity of nano-WC-Co in the co-culture model compared to BEAS-2B alone, which indicated a protective effect of the macrophages. We found that nano-WC-Co exposure caused macrophage polarization toward the M1 pro-inflammatory phenotype and determined that nano-WC-Co exposure also stimulates the secretion of cytokines such as IL-12 and IL-1beta in macrophages, consistent with a pro-inflammatory response. In Aim 3, we investigated the potential systemic (extra-pulmonary) effects of nano-WC-Co exposure in an intra-tracheal instillation (IT) rat model and compared the outcomes with a known pulmonary irritant, cerium dioxide (CeO2). After 24 hr exposure, nano-WC-Co exposure did not induce pulmonary or systemic inflammation at a dose of 50, 250 or 500 mug compared to control or CeO2; this outcome highlights the need for future in vivo studies which examine the inflammatory effects of chronic or repeated nano-WC-Co exposure. Taken together, the results of our studies improve the current understanding of hard metal WC-Co toxicity and may point toward potential therapeutic or diagnostic strategies for the future