Advances in the Treatment of Renal Cell Carcinoma

This Special Issue of Cancers focuses on new advances in the treatment of renal cell carcinoma, both surgical and pharmacological (and combinations of these), and novel approaches to tackle treatment resistance and improve our understanding of this phenomenon

Recent advances in understanding pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is an intractable cancer and a leading cause of cancer deaths worldwide. Over 90% of patients die within 1 year of diagnosis. Deaths from PDAC are increasing and it remains a cancer of substantial unmet need. A number of factors contribute to its poor prognosis: namely, late presentation, early metastases and limited systemic therapy options because of chemoresistance. A variety of research approaches underway are aimed at improving patient survival. Here, we review high-risk groups and efforts for early detection. We examine recent developments in the understanding of complex molecular and metabolic alterations which accompany PDAC. We explore artificial intelligence and biological targets for therapy and examine the role of tumour stroma and the immune microenvironment. We also review recent developments with respect to the PDAC microbiome. It is hoped that current research efforts will translate into earlier diagnosis, improvements in treatment and better outcomes for patients

DEVELOPMENT AND CHARACTERIZATION OF NEW pan-SIGMA RECEPTOR MODULATORS: CHEMICAL, BIOLOGICAL AND PHARMACOLOGICAL STUDIES FOR PRECLINICAL VALIDATION OF NEW THERAPEUTIC TARGETS

Two sigma receptor subtypes (SR) have been identified to date, the sigma 1 receptor (S1R) and the sigma 2 receptor (S2R), differentiable by pharmacological profile, size, subcellular location and function. In recent decades, SRs have been proposed as innovative therapeutic targets for the treatment of tumors, being involved in mechanisms of cancer cell proliferation and survival. This has strengthened the interest of the pharmaceutical chemistry field for the identification and study of molecules related to both receptor subtypes as potential anticancer agents. This PhD project fits into this scenario and has two main objectives: (i) to develop and validate a new approach for cancer treatment based on pan-SRs modulators, using RC-106, a previously identified new pan-SRs modulator, as a pharmacological tool; (ii) to develop and characterize new RC-106 analogs with good affinity for both receptor subtypes and with antitumor activity. To achieve objective (i) RC-106 was the subject of a large biological study conducted on a panel of pancreatic cancer cell lines. On this panel, the antiproliferative and pro-apoptotic activity of RC-106 was studied, showing effectiveness at micromolar concentrations (IC50). In parallel, the biodistribution profile of RC-106 in mice was investigated. The compound was found to be 25 times more concentrated in the pancreas than in the plasma, reaching a concentration in the target organ at least equal to that effective in all performed in vitro experiments. Furthermore, the ability of RC-106 to overcome the blood brain barrier suggests the potential use of the molecule also for the treatment of brain tumors. Once the anticancer activity of RC-106 had been validated, the work focused on the characterization of the molecular mechanisms underlying this activity. Since SRs are mainly localized at the interface between the endoplasmic reticulum (ER) and mitochondria and due to their current re-classification as ligand-activated chaperones, we hypothesized their potential role in regulating the response of cells to ER stress. To validate this hypothesis, we focused on a particular adaptive mechanism, known as Unfolded Protein Response (UPR). This mechanism, in conditions of chronic stress, switches from a cell survival signal to a signal of death and takes the name of terminal UPR, triggering programmed cell death. We hypothesized that, the modulation of SRs activity in tumor cells could induce the activation of terminal UPR, thus causing cell death. The data obtained showed that the anticancer activity of RC-106 is related to the activation of the terminalUPR and to the inhibition of the proteasome. From a more general point of view, our data support the hypothesis of pan-SRs modulators as a valid tool for pharmacological studies aimed at a better knowledge of this class of receptors. Finally, to further define the role of SRs in tumors, we planned confocal microscopy imaging studies aimed at localizing and tracing SRs at the intracellular level and obtaining information on the mechanism of internalization, uptake and retention of RC-106. First, the fluorescence spectrum of RC-106 was studied, showing a fluorescence emission very similar to that of the endogenous fluorophores present in the cells. Therefore, RC-106 was not found to be usable for imaging studies. We then designed two hydroxylated derivatives of RC-106, RC-172 and RC-174, suitable for the subsequent introduction of a fluorescent tag. Relative to the objective (ii), we designed and prepared RC-106 analogs characterized by the presence of a variously functionalized piperazine ring, using a combinatorial approach and finally evaluated their cytotoxic activity in multiple myeloma (MM) cell lines and in glioblastoma (GB). The results obtained led to the identification of two compounds with an interesting antitumor potential useful for the treatment of MM, and one worthy of further investigations for the treatment of GB.Two sigma receptor subtypes (SR) have been identified to date, the sigma 1 receptor (S1R) and the sigma 2 receptor (S2R), differentiable by pharmacological profile, size, subcellular location and function. In recent decades, SRs have been proposed as innovative therapeutic targets for the treatment of tumors, being involved in mechanisms of cancer cell proliferation and survival. This has strengthened the interest of the pharmaceutical chemistry field for the identification and study of molecules related to both receptor subtypes as potential anticancer agents. This PhD project fits into this scenario and has two main objectives: (i) to develop and validate a new approach for cancer treatment based on pan-SRs modulators, using RC-106, a previously identified new pan-SRs modulator, as a pharmacological tool; (ii) to develop and characterize new RC-106 analogs with good affinity for both receptor subtypes and with antitumor activity. To achieve objective (i) RC-106 was the subject of a large biological study conducted on a panel of pancreatic cancer cell lines. On this panel, the antiproliferative and pro-apoptotic activity of RC-106 was studied, showing effectiveness at micromolar concentrations (IC50). In parallel, the biodistribution profile of RC-106 in mice was investigated. The compound was found to be 25 times more concentrated in the pancreas than in the plasma, reaching a concentration in the target organ at least equal to that effective in all performed in vitro experiments. Furthermore, the ability of RC-106 to overcome the blood brain barrier suggests the potential use of the molecule also for the treatment of brain tumors. Once the anticancer activity of RC-106 had been validated, the work focused on the characterization of the molecular mechanisms underlying this activity. Since SRs are mainly localized at the interface between the endoplasmic reticulum (ER) and mitochondria and due to their current re-classification as ligand-activated chaperones, we hypothesized their potential role in regulating the response of cells to ER stress. To validate this hypothesis, we focused on a particular adaptive mechanism, known as Unfolded Protein Response (UPR). This mechanism, in conditions of chronic stress, switches from a cell survival signal to a signal of death and takes the name of terminal UPR, triggering programmed cell death. We hypothesized that, the modulation of SRs activity in tumor cells could induce the activation of terminal UPR, thus causing cell death. The data obtained showed that the anticancer activity of RC-106 is related to the activation of the terminalUPR and to the inhibition of the proteasome. From a more general point of view, our data support the hypothesis of pan-SRs modulators as a valid tool for pharmacological studies aimed at a better knowledge of this class of receptors. Finally, to further define the role of SRs in tumors, we planned confocal microscopy imaging studies aimed at localizing and tracing SRs at the intracellular level and obtaining information on the mechanism of internalization, uptake and retention of RC-106. First, the fluorescence spectrum of RC-106 was studied, showing a fluorescence emission very similar to that of the endogenous fluorophores present in the cells. Therefore, RC-106 was not found to be usable for imaging studies. We then designed two hydroxylated derivatives of RC-106, RC-172 and RC-174, suitable for the subsequent introduction of a fluorescent tag. Relative to the objective (ii), we designed and prepared RC-106 analogs characterized by the presence of a variously functionalized piperazine ring, using a combinatorial approach and finally evaluated their cytotoxic activity in multiple myeloma (MM) cell lines and in glioblastoma (GB). The results obtained led to the identification of two compounds with an interesting antitumor potential useful for the treatment of MM, and one worthy of further investigations for the treatment of GB

Personalized Systemic Therapies in Hereditary Cancer Syndromes

Hereditary cancer syndromes are inherited disorders caused by germline pathogenic variants (PVs) that lead to an increased risk of developing certain types of cancer, frequently at an earlier age than in the rest of the population. The germline PVs promote cancer development, growth and survival, and may represent an ideal target for the personalized treatment of hereditary tumors. PARP inhibitors for the treatment of BRCA and PALB2-associated tumors, immune checkpoint inhibitors for tumors associated with the Lynch Syndrome, HIF-2α inhibitor in the VHL-related cancers and, finally, selective RET inhibitors for the treatment of MEN2-associated medullary thyroid cancer are the most successful examples of how a germline PVs can be exploited to develop effective personalized therapies and improve the outcome of these patients. The present review aims to describe and discuss the personalized systemic therapies for inherited cancer syndromes that have been developed and investigated in clinical trials in recent decades

Oncolytic Virus Immunotherapy

Dear Readers, Oncolytic Viruses (OV) are self-propagating agents that can selectively induce the lysis of cancer cells while sparing normal tissues. OV-mediated cancer cell death is often immunogenic and triggers robust anticancer immune responses and immunoconversion of tumor microenvironments. This makes oncolytic virotherapy a promising new form of immunotherapy and OVs ideal candidates for combination therapy with other anticancer agents, including other immunotherapeutics. There are more than 40 OVs from nine different families in clinical development and many more at the preclinical stage. Each OV has its own unique characteristics, its pros and cons. Although herpes simplex virus is currently the lead clinical agent, a real champion among the OVs has not yet emerged, justifying the continuous development and optimization of these agents. This book, “Oncolytic Virus Immunotherapy”, summarizes the state-of-the-art and gives a comprehensive overview of the OV arena with a particular focus on new trends, directions, challenges, and opportunities

Doctor of Philosophy

dissertationThe overall objective of this project is to develop methods that can help us to understand the movement of drugs and carriers along their routes inside solid tumors. The origins and current paradigm of targeted drug delivery offer a lot of promising strategies. However, the carriers often struggle with challenges in optimizing their own characteristics against that of the tumor's. Ultimately, they struggle with translation into the clinical setting. It is apparent that solid tumors pose a unique challenge in drug delivery. Many drug carrier characteristics are designed to take advantage of the pathophysiology of the tumor environment. However, this passive delivery and accumulation is constrained to partial distribution within the tumor. Many uncertainties remain regarding how nanoparticles enter and travel through the tumor environment. The barriers to intratumoral distribution are still currently being probed. The research herein identified transport barriers using human fibroid tumors known to have impaired drug transport. After perfusing human uteri containing fibroids with stains, probe distribution was found to correlate with features of the pathophysiology such as blood vessel characteristics, tissue and collagen density, interstitial fluid pressure, and solid stress. Methods, including custom MATLAB code, were developed to analyze the spatiotemporal distribution of two uniquely fluorescent nanoparticle doses in xenograft mice. It shows how three-dimensional distance measurements of nanoparticles from nearest blood vessels are more precise than two-dimensional measurements. Colocalization analysis on the fluorescent signals showed the two different doses (administered hours apart from each other) did not accumulate in the same locations with the tumor. Furthermore, intravital imaging showed that some vessels of the tumor would only provide access to the first dose of nanoparticles. Future work suggests further analysis of multidose interdependence and implementing these methods to screen strategies in the literature of modifying drug carriers and the tumor environment to improve intratumoral distribution of cancer drugs. The more understanding we have of the solid tumor environment and its barriers, the better we can navigate treatments to reach the tumor

Improving the evaluation and treatment of neuroendocrine disorders

The aim of this thesis was to improve the diagnosis and treatment of neuroendocrine disorders. In addition, it shows further possibilities to achieve this goal in the long term

Improving the evaluation and treatment of neuroendocrine disorders

The aim of this thesis was to improve the diagnosis and treatment of neuroendocrine disorders. In addition, it shows further possibilities to achieve this goal in the long term

Chitosan in non-viral gene delivery: Role of structure, characterization methods, and insights in cancer and rare diseases therapy

Non-viral gene delivery vectors have lagged far behind viral ones in the current pipeline of clinical trials of gene therapy nanomedicines. Even when non-viral nanovectors pose less safety risks than do viruses, their efficacy is much lower. Since the early studies to deliver pDNA, chitosan has been regarded as a highly attractive biopolymer to deliver nucleic acids intracellularly and induce a transgenic response resulting in either upregulation of protein expression (for pDNA, mRNA) or its downregulation (for siRNA or microRNA). This is explained as the consequence of a multi-step process involving condensation of nucleic acids, protection against degradation, stabilization in physiological conditions, cellular internalization, release from the endolysosome (“proton sponge” effect), unpacking and enabling the trafficking of pDNA to the nucleus or the siRNA to the RNA interference silencing complex (RISC). Given the multiple steps and complexity involved in the gene transfection process, there is a dearth of understanding of the role of chitosan’s structural features (Mw and degree of acetylation, DA%) on each step that dictates the net transfection efficiency and its kinetics. The use of fully characterized chitosan samples along with the utilization of complementary biophysical and biological techniques is key to bridging this gap of knowledge and identifying the optimal chitosans for delivering a specific gene. Other aspects such as cell type and administration route are also at play. At the same time, the role of chitosan structural features on the morphology, size and surface composition of synthetic virus-like particles has barely been addressed. The ongoing revolution brought about by the recent discovery of CRISPR-Cas9 technology will undoubtedly be a game changer in this field in the short term. In the field of rare diseases, gene therapy is perhaps where the greatest potential lies and we anticipate that chitosans will be key players in the translation of research to the clinic