An unexpected cell-penetrating peptide from Bothrops jararaca venom identified through a novel size exclusion chromatography screening.

Efficient drug delivery systems are currently one of the greatest challenges in pharmacokinetics, and the transposition of the gap between in vitro candidate molecule and in vivo test drug is, sometimes, poles apart. In this sense, the cell-penetrating peptides (CPP) may be the bridge uniting these worlds. Here, we describe a technique to rapidly identify unlabeled CPPs after incubation with liposomes, based on commercial desalting (size exclusion) columns and liquid chromatography-MS/MS, for peptide de novo sequencing. Using this approach, we found it possible to identify one new CPP - interestingly, a classical bradykinin-potentiating peptide - in the peptide-rich low molecular mass fraction of the Bothrops jararaca venom, which was also able to penetrate live cell membranes, as confirmed by classical approaches employing fluorescence-labeled analogues of this CPP. Moreover, both the labeled and unlabeled CPPs caused no metabolic, cell-cycle or morphologic alterations, proving to be unmistakably cargo deliverers and not drugs themselves. In sum, we have developed and validated a method for screening label-free peptides for CPP activity, regardless of their biological origin, which could lead to the identification of new and more efficient drug delivery systems. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.

RPF101, a new capsaicin-like analogue, disrupts the microtubule network accompanied by arrest in the G2/M phase, inducing apoptosis and mitotic catastrophe in the MCF-7 breast cancer cells.

Breast cancer is the world's leading cause of death among women. This situation imposes an urgent development of more selective and less toxic agents. The use of natural molecular fingerprints as sources for new bioactive chemical entities has proven to be a quite promising and efficient method. Capsaicin, which is the primary pungent compound in red peppers, was reported to selectively inhibit the growth of a variety tumor cell lines. Here, we report for the first time a novel synthetic capsaicin-like analogue, RPF101, which presents a high antitumor activity on MCF-7 cell line, inducing arrest of the cell cycle at the G2/M phase through a disruption of the microtubule network. Furthermore, it causes cellular morphologic changes characteristic of apoptosis and a decrease of Δψm. Molecular modeling studies corroborated the biological findings and suggested that RPF101, besides being a more reactive molecule towards its target, may also present a better pharmacokinetic profile than capsaicin. All these findings support the fact that RPF101 is a promising anticancer agent.

Sleep disorders and prostate cancer prognosis: biology, epidemiology, and association with cancer development risk.

Sleep is crucial for the maintenance of health and well-being. Sleep disorders can result in physiological consequences and are associated with several health issues, including cancer. Cancer is one of the most significant health problems in the world. In Western countries, prostate cancer is the most prevalent noncutaneous cancer among men. Epidemiological studies showed that one in nine men will have this disease during their life. Many factors influence prostate cancer and the tumor niche, including endogenous hormones, family history, diet, and gene mutations. Disruption of the circadian cycle by sleep disorders or other factors has been suggested as a novel and important risk factor for prostate cancer and its tumorigenesis. This review presents information regarding the epidemiological and biological aspects of prostate cancer, and discusses the impact of sleep physiology and sleep disorders on this type of cancer, highlighting possible associations with risk of cancer development.

Adipose Tissue-Derived Stem Cells: The Biologic Basis and Future Directions for Tissue Engineering.

Mesenchymal stem cells (MSCs) have been isolated from a variety of tissues using different methods. Active research have confirmed that the most accessible site to collect them is the adipose tissue; which has a significantly higher concentration of MSCs. Moreover; harvesting from adipose tissue is less invasive; there are no ethical limitations and a lower risk of severe complications. These adipose-derived stem cells (ASCs) are also able to increase at higher rates and showing telomerase activity, which acts by maintaining the DNA stability during cell divisions. Adipose-derived stem cells secret molecules that show important function in other cells vitality and mechanisms associated with the immune system, central nervous system, the heart and several muscles. They release cytokines involved in pro/anti-inflammatory, angiogenic and hematopoietic processes. Adipose-derived stem cells also have immunosuppressive properties and have been reported to be "immune privileged" since they show negative or low expression of human leukocyte antigens. Translational medicine and basic research projects can take advantage of bioprinting. This technology allows precise control for both scaffolds and cells. The properties of cell adhesion, migration, maturation, proliferation, mimicry of cell microenvironment, and differentiation should be promoted by the printed biomaterial used in tissue engineering. Self-renewal and potency are presented by MSCs, which implies in an open-source for 3D bioprinting and regenerative medicine. Considering these features and necessities, ASCs can be applied in the designing of tissue engineering products. Understanding the heterogeneity of ASCs and optimizing their properties can contribute to making the best therapeutic use of these cells and opening new paths to make tissue engineering even more useful.

Antitumoral effects of Amblyomma sculptum Berlese saliva in neuroblastoma cell lines involve cytoskeletal deconstruction and cell cycle arrest.

The antitumor properties of ticks salivary gland extracts or recombinant proteins have been reported recently, but little is known about the antitumor properties of the secreted components of saliva. The goal of this study was to investigate the in vitro effect of the saliva of the hard tick Amblyomma sculptum on neuroblastoma cell lines. SK-N-SK, SH-SY5Y, Be(2)-M17, IMR-32, and CHLA-20 cells were susceptible to saliva, with 80% reduction in their viability compared to untreated controls, as demonstrated by the methylene blue assay. Further investigation using CHLA-20 revealed apoptosis, with approximately 30% of annexin-V positive cells, and G0/G1-phase accumulation (>60%) after treatment with saliva. Mitochondrial membrane potential (Δψm) was slightly, but significantly (p < 0.05), reduced and the actin cytoskeleton was disarranged, as indicated by fluorescent microscopy. The viability of human fibroblast (HFF-1 cells) used as a non-tumoral control decreased by approximately 40%. However, no alterations in cell cycle progression, morphology, and Δψm were observed in these cells. The present work provides new perspectives for the characterization of the molecules present in saliva and their antitumor properties.

The Roles of ROS in Cancer Heterogeneity and Therapy.

Cancer comprises a group of heterogeneous diseases encompassing high rates of morbidity and mortality. Heterogeneity, which is a hallmark of cancer, is one of the main factors related to resistance to chemotherapeutic agents leading to poor prognosis. Heterogeneity is profoundly affected by increasing levels of ROS. Under low concentrations, ROS may function as signaling molecules favoring tumorigenesis and heterogeneity, while under high ROS concentrations, these species may work as cancer modulators due to their deleterious, genotoxic or even proapoptotic effect on cancer cells. This double-edged sword effect represented by ROS relies on their ability to cause genetic and epigenetic modifications in DNA structure. Antitumor therapeutic approaches may use molecules that prevent the ROS formation precluding carcinogenesis or use chemical agents that promote a sudden increase of ROS causing considerable oxidative stress inside tumor mass. Therefore, herein, we review what ROS are and how they are produced in normal and in cancer cells while providing an argumentative discussion about their role in cancer pathophysiology. We also describe the various sources of ROS in cancer and their role in tumor heterogeneity. Further, we also discuss some therapeutic strategies from the current landscape of cancer heterogeneity, ROS modulation, or ROS production.

Advances and Challenges on Cancer Cells Reprogramming Using Induced Pluripotent Stem Cells Technologies.

Cancer cells transformation into a normal state or into a cancer cell population which is less tumorigenic than the initial one is a challenge that has been discussed during last decades and it is still far to be solved. Due to the highly heterogeneous nature of cancer cells, such transformation involves many genetic and epigenetic factors which are specific for each type of tumor. Different methods of cancer cells reprogramming have been established and can represent a possibility to obtain less tumorigenic or even normal cells. These methods are quite complex, thus a simple and efficient method of reprogramming is still required. As soon as induced pluripotent stem cells (iPSC) technology, which allowed to reprogram terminally differentiated cells into embryonic stem cells (ESC)-like, was developed, the method strongly attracted the attention of researches, opening new perspectives for stem cell (SC) personalized therapies and offering a powerful in vitro model for drug screening. This technology is also used to reprogram cancer cells, thus providing a modern platform to study cancer-related genes and the interaction between these genes and the cell environment before and after reprogramming, in order to elucidate the mechanisms of cancer initiation and progression. The present review summarizes recent advances on cancer cells reprogramming using iPSC technology and shows the progress achieved in such field.

Apoptotic effect of eugenol envolves G2/M phase abrogation accompanied by mitochondrial damage and clastogenic effect on cancer cell in vitro.

BACKGROUND: Eugenol (EUG) is a major phenolic compound present in clove whose anti-cancer properties have been demonstrated previously. These anti-cancer properties may involves the modulation of different mechanisms, including α-estrogen receptor (αER) in luminal breast cancer cells, COX-2 inhibition in melanoma cells or p53 and caspase-3 activation in colon cancer cells. HYPOTHESIS: EUG promotes a burst in ROS production causing cell-cycle perturbations, mitochondria toxicity and clastogenesis triggering apoptosis in melanoma breast- and cervix-cancer cells in vitro. METHODS: Morphological changes were evaluated through the light- and electronic- microscopy. Cell-cycle, ROS, PCNA and Apoptosis was detected by flow cytometry and clastogenicity was evaluated by Comet-assay. RESULTS: The results obtained herein pointed out that EUG promotes, increasing ROS production leading to abrogation of G2/M of phase of cell-cycle, and consecutively, clastogenesis in vitro. In addition, EUG induces Proliferation Cell Nuclear Antigen (PCNA) downregulation and decreasing in mitochondria potential (ΔΨm). Of note, a Bax up-regulation was also observed on cells treated with EUG. All of these findings cooperate in order to induce apoptosis in cancer cells. CONCLUSION: These promising results presented herein shed new light on the mechanisms of action of EUG suggesting a possible applicability of this phenylpropanoid as adjuvant in anti-cancer therapy.

Cytotoxic effects of dillapiole on MDA-MB-231 cells involve the induction of apoptosis through the mitochondrial pathway by inducing an oxidative stress while altering the cytoskeleton network.

Breast cancer is the world's leading cause of death among women. This situation imposes an urgent development of more selective and less toxic agents. The use of natural molecular fingerprints as sources for new bioactive chemical entities has proven to be a quite promising and efficient method. Here, we have demonstrated for the first time that dillapiole has broad cytotoxic effects against a variety tumor cells. For instance, we found that it can act as a pro-oxidant compound through the induction of reactive oxygen species (ROS) release in MDA-MB-231 cells. We also demonstrated that dillapiole exhibits anti-proliferative properties, arresting cells at the G0/G1 phase and its antimigration effects can be associated with the disruption of actin filaments, which in turn can prevent tumor cell proliferation. Molecular modeling studies corroborated the biological findings and suggested that dillapiole may present a good pharmacokinetic profile, mainly because its hydrophobic character, which can facilitate its diffusion through tumor cell membranes. All these findings support the fact that dillapiole is a promising anticancer agent.

Antitumoral effects of Amblyomma sculptum Berlese saliva in neuroblastoma cell lines involve cytoskeletal deconstruction and cell cycle arrest / Efeito antitumoral da saliva do carrapato Amblyomma sculptum Berlese em células de neuroblastoma envolve desconstrução do citoesqueleto e parada do ciclo celular

Abstract The antitumor properties of ticks salivary gland extracts or recombinant proteins have been reported recently, but little is known about the antitumor properties of the secreted components of saliva. The goal of this study was to investigate the in vitro effect of the saliva of the hard tick Amblyomma sculptum on neuroblastoma cell lines. SK-N-SK, SH-SY5Y, Be(2)-M17, IMR-32, and CHLA-20 cells were susceptible to saliva, with 80% reduction in their viability compared to untreated controls, as demonstrated by the methylene blue assay. Further investigation using CHLA-20 revealed apoptosis, with approximately 30% of annexin-V positive cells, and G0/G1-phase accumulation (>60%) after treatment with saliva. Mitochondrial membrane potential (Δψm) was slightly, but significantly (p < 0.05), reduced and the actin cytoskeleton was disarranged, as indicated by fluorescent microscopy. The viability of human fibroblast (HFF-1 cells) used as a non-tumoral control decreased by approximately 40%. However, no alterations in cell cycle progression, morphology, and Δψm were observed in these cells. The present work provides new perspectives for the characterization of the molecules present in saliva and their antitumor properties.

Resumo As propriedades antitumorais de extratos de glândulas salivares de carrapatos ou proteínas recombinantes foram relatadas recentemente, mas pouco se sabe sobre as propriedades antitumorais dos componentes secretados da saliva. O objetivo deste estudo foi investigar o efeito in vitro da saliva bruta do carrapato duro Amblyomma sculptum sobre as linhagens celulares de neuroblastoma. Células SK-N-SK, SH-SY5Y, Be(2)-M17, IMR-32 e CHLA-20 foram suscetíveis à saliva, com redução de 80% na sua viabilidade em comparação com controles não tratados, como demonstrado pelo ensaio de Azul de Metileno. Investigações posteriores utilizando CHLA-20 revelaram apoptose, com aproximadamente 30% de células positivas para anexina-V, e G0/G1 (> 60%) após tratamento com saliva. O potencial de membrana mitocondrial (Δψm) foi reduzido significativamente (p <0,05), e o citoesqueleto de actina foi desestruturado, como indicado pela microscopia de fluorescência. A viabilidade do fibroblasto humano (células HFF-1), usado como controle não tumoral, diminuiu em aproximadamente 40%. No entanto, não foram observadas alterações na progressão do ciclo celular, morfologia e Δψm nestas células. O presente trabalho fornece novas perspectivas para a caracterização das moléculas presentes na saliva e suas propriedades antitumorais.