Liver transplantation with grafts obtained after cardiac death-current advances in mastering the challenge

The scarcity of donor livers has increased the interest in donation after cardiac death (DCD) as an additional pool to expand the availability of organs. However, the initial results of liver transplantation with DCD grafts have been suboptimal due to an increased rate of complications, as well as decreased graft survival. These challenges have led to many developments in DCD donation outcome, as well as basic and translational research. In this article we review the unique characteristics of DCD donors, nuances of DCD organ procurement, the effect of prolonged warm and cold ischemia times, and discuss major studies that compared DCD to donation after brain death liver transplantation, in terms of outcomes and complications. We also review the different methods of donor treatment that has been applied to ameliorate DCD organ outcome, and we discuss the role of machine perfusion techniques in organ reconditioning. We discuss the two major perfusion models, namely, hypothermic machine perfusion and normothermic machine perfusion; we compare both methods, and delineate their major differences.

Component-resolved allergen testing: The new frontier

The discovery that allergen specific IgE (sIgE) identified individuals who were allergic to specific allergens, revolutionized allergy and immunology. Recently, component-resolved allergen testing (CRD) has shown promise in improving the field yet again. Prior to development of CRD immunoassays, whole allergen extracts were used to detect IgE mediated allergic disease either by oral, cutaneous, or conjunctival provocation. The most widely used immunoassays detect sIgE to either whole allergen sources or individual allergic components. The use of CRD micro-assay technology (not Food and Drug Administration approved in the United States) has been used to evaluate multiple allergens in parallel. This technique allows for determination of primary vs secondary sensitizations from either close sequence homology or cross-reactive carbohydrate determinants. Published studies have shown beneficial uses in hymenoptera venom immunotherapy, anaphylaxis, and food allergy. The use of component testing for aeroallergen immunotherapy has been studied, however clinical use is hampered by lack of allergen components approved for injection. Therefore, although promising in many respects, the frontier of CRD testing requires more data before it can be widely used in clinical practice.

Therapeutic targets in gastrointestinal stromal tumors

Gastrointestinal stromal tumors (GISTs) are the most common type of mesenchymal tumor of the gastrointestinal tract. The tumorigenesis of GISTs is driven by gain-of-function mutations in KIT or platelet-derived growth factor receptor α (PDGFRA), resulting in constitutive activation of the tyrosine kinase and its downstream signaling pathways. Oncogenic KIT or PDGFRA mutations are compelling therapeutic targets for the treatment of GISTs, and the KIT/PDGFRA inhibitor imatinib is the standard of care for patients with metastatic GISTs. However, most GIST patients develop clinical resistance to imatinib and other tyrosine kinase inhibitors. Five mechanisms of resistance have been characterized: (1) acquisition of a secondary point mutation in KIT or PDGFRA; (2) genomic amplification of KIT; (3) activation of an alternative receptor tyrosine kinase; (4) loss of KIT oncoprotein expression; and (5) wild-type GIST. Currently, sunitinib is used as a second-line treatment for patients after imatinib failure, and regorafenib has been approved for patients whose disease is progressing on both imatinib and sunitinib. Phase II/III trials are currently in progress to evaluate novel inhibitors and immunotherapies targeting KIT, its downstream effectors such as phosphatidylinositol 3-kinase, protein kinase B and mammalian target of rapamycin, heat shock protein 90, and histone deacetylase inhibitor. Other candidate targets have been identified, including ETV1, AXL, insulin-like growth factor 1 receptor, KRAS, FAS receptor, protein kinase c theta, ANO1 (DOG1), CDC37, and aurora kinase A. These candidates warrant clinical evaluation as novel therapeutic targets in GIST.

Potential therapeutic targets from genetic and epigenetic approaches for asthma

Asthma is a complex disorder characterised by inflammation of airway and symptoms of wheeze and shortness of breath. Allergic asthma, atopic dermatitis and allergic rhinitis are immunoglobulin E (IgE) related diseases. Current therapies targeting asthma rely on non-specific medication to control airway inflammation and prevent symptoms. Severe asthma remains difficult to treat. Genetic and genomic approaches of asthma and IgE identified many novel loci underling the disease pathophysiology. Recent epigenetic approaches also revealed the insights of DNA methylation and chromatin modification on histones in asthma and IgE. More than 30 microRNAs have been identified to have regulating roles in asthma. Understanding the pathways of the novel genetic loci and epigenetic elements in asthma and IgE will provide new therapeutic means for clinical management of the disease in future.

Pro- vs anti-stenotic capacities of type-I vs type-II human induced pluripotent-derived endothelial cells

AIM: To verify in vivo relevance of the categorization of human vascular endothelial cells (VECs) into type-I (pro-proliferative) and type-II (anti-proliferative).

METHODS: Endothelial layers of murine femoral arteries were removed by wire injury (WI) operation, a common technique to induce arteriostenosis. Type-I and type-II VECs produced from human induced pluripotent stem cells (iPSCs), whose characters were previously determined by their effects on the proliferation of vascular smooth muscle cells in in vitro co-culture experiments, were mixed with Matrigel^® Matrix. The mixtures were injected into subcutaneous spaces around WI-operated femoral arteries for the transplanted human iPSC-derived VECs (iPSdECs) to take a route to the luminal surface via vasa vasorum, a nutrient microvessel for larger arteries. Histologies of the femoral arteries were examined over time. The presence of human iPSdECs was checked by immunostaining studies using an antibody that specifically recognizes human VECs. Degrees of stenosis of the femoral arteries were calculated after three weeks. To determine the optimal experimental condition, xenotransplantation experiments were performed under various conditions using immunocompromised mice as well as immunocompetent mice with or without administration of immunosuppressants.

RESULTS: Because immunocompromised mice showed unexpected resistance to WI-induced arteriostenosis, we performed xenotransplantation experiments using immunocompetent mice along with immunosuppressant administrations. After one week, luminal surfaces of the WI-operated arteries were completely covered by human iPSdECs, showing the efficacy of our novel transplantation technique. After three weeks, type-I-iPSdECs-transplanted arteries underwent total stenosis, while type-II-iPSdECs-transplanted arteries remained intact. However, untransplanted arteries of immunosuppressant-treated mice also remained intact by unknown reasons. We found that transplanted human VECs had already been replaced by murine endothelial cells by this time, indicating that a transient existence of human type-II-iPSdECs on arterial luminal surfaces can sufficiently prevent the development of stenosis. Thus, we re-performed xenotransplantation experiments using immunocompetent mice without administrating immunosuppressants and found that arteriostenosis was accelerated or prevented by transplantation of type-I or type-II iPSdECs, respectively. Similar results were obtained from the experiments using human embryonic stem cell-derived VECs at early passages (i.e., type-II) and late passages (i.e., type-I).

CONCLUSION: Pro- and anti-stenosis capacities of type-I and type-II human iPSdECs were verified, respectively, promising a therapeutic application of allogenic iPSdECs.

Prednisolone inhibits SaOS2 osteosarcoma cell proliferation by activating inducible nitric oxide synthase

AIM: To investigate the effect of prednisolone, a synthetic glucocorticoid used in inflammatory diseases, on the growth of cultured osteosarcoma cells.

METHODS: Two osteosarcoma cell lines with different degree of differentiation were used. SaOS2 show a rather mature phenotype, while U2OS are negative for almost all osteoblastic markers. The cells were exposed to different concentrations of prednisolone (1-9 μmol/L) with or without antioxidants or the inhibitor of inducible nitric oxide synthase (iNOS) l-N⁶-(iminoethyl)-lysine-HCl (L-NIL). Cell growth was assessed by counting viable cells. The production of nitric oxide (NO) was measured in the conditioned media by the Griess method. The production of reactive oxygen species was quantified using 2’-7’-dichlorofluorescein diacetate. Western blot with specific antibodies against NOSs was performed on cell extracts.

RESULTS: Prednisolone inhibited SaOS2 cell growth in a dose dependent manner. No significant effects were observed in U2OS. The inhibition of SaOS2 growth is not due to oxidative stress, because antioxidants do not rescue cell proliferation. Since high concentrations of NO inhibit bone formation, we also measured NO and found it induced in SaOS2, but not in U2OS, exposed to prednisolone, because of the upregulation of iNOS as detected by western blot. Therefore, we treated SaOS2 with prednisolone in the presence or in the absence of L-NIL. L-NIL prevented NO release induced by prednisolone at all the concentrations apart from 9 μmol/L. At the same concentrations, we found that L-NIL rescued SaOS2 growth after exposure to prednisolone. In U2OS cells, prednisolone did not induce NO production nor affected cell growth. All together, these data indicate that a link exists between increased amounts of NO and growth inhibition in response to prednisolone in SaOS2.

CONCLUSION: Prednisolone inhibited SaOS2 proliferation by increasing the release of NO through the upregulation of iNOS, while no effect was exerted on U2OS.

Pharmacogenetics of type 2 diabetes mellitus: An example of success in clinical and translational medicine

The pharmacological interventions currently available to control type 2 diabetes mellitus (T2DM) show a wide interindividual variability in drug response, emphasizing the importance of a personalized, more effective medical treatment for each individual patient. In this context, a growing interest has emerged in recent years and has focused on pharmacogenetics, a discipline aimed at understanding the variability in patients’ drug response, making it possible to predict which drug is best for each patient and at what doses. Recent pharmacological and clinical evidences indicate that genetic polymorphisms (or genetic variations) of certain genes can adversely affect drug response and therapeutic efficacy of oral hypoglycemic agents in patients with T2DM, through pharmacokinetic- and/or pharmacodynamic-based mechanisms that may reduce the therapeutic effects or increase toxicity. For example, genetic variants in genes encoding enzymes of the cytochrome P-450 superfamily, or proteins of the ATP-sensitive potassium channel on the beta-cell of the pancreas, are responsible for the interindividual variability of drug response to sulfonylureas in patients with T2DM. Instead, genetic variants in the genes that encode for the organic cation transporters of metformin have been related to changes in both pharmacodynamic and pharmacokinetic responses to metformin in metformin-treated patients. Thus, based on the individual’s genotype, the possibility, in these subjects, of a personalized therapy constitutes the main goal of pharmacogenetics, directly leading to the development of the right medicine for the right patient. Undoubtedly, this represents an integral part of the translational medicine network.

p38 mitogen-activated protein kinase regulates type-I vs type-II phenotyping of human vascular endothelial cells

AIM: To identify kinases involved in phenotype regulation of vascular endothelial cells (VECs): Pro-proliferative G-protein signaling 5 (RGS5)^high (type-I) vs anti-proliferative RGS5^low (type-II) VECs.

METHODS: Proteomic kinase assays were performed to identify the crucial kinase involved in the phenotype regulation of human VECs using type-I VECs, which promotes the proliferation of human vascular smooth muscle cells (VSMCs), and type-II VECs, which suppress the proliferation of human VSMCs. The assays were performed using multiple pairs of type-I and type-II VECs to obtain the least number of candidates. The involvement of the candidate kinases was verified by evaluating the effects of their specific inhibitors on the phenotype regulation of human VECs as well as the expression levels of regulator of RGS5, which is the causative gene for the “type-II to type-I” phenotype conversion of human VECs.

RESULTS: p38α mitogen-activated protein kinase (p38α MAPK) was the only kinase that showed distinctive activities between type-I and type-II VECs: p38α MAPK activities were low and high in type-I and type-II VECs, respectively. We found that an enforced expression of RGS5 indeed lowered p38α MAPK activities in type-II VECs. Furthermore, treatments with a p38α MAPK inhibitor nullified the anti-proliferative potential in type-II VECs. Interestingly, MAPK inhibitor treatments enhanced the induction of RGS5 gene. Thus, there is a vicious cycle between “RGS5 induction” and “p38α MAPK inhibition”, which can explain the unidirectional process in the stress-induced “type-II to type-I” conversions of human VECs. To understand the upstream signaling of RGS5, which is known as an inhibitory molecule against the G protein-coupled receptor (GPCR)-mediated signaling, we examined the effects of RGS5 overexpression on the signaling events from sphingosine-1-phosphate (S1P) to N-cadherin, because S1P receptors belong to the GPCR family gene and N-cadherin, one of their downstream effectors, is reportedly involved in the regulation of VEC-VSMC interactions. We found that RGS5 specifically bound with S1P₁. Moreover, N-cadherin localization at intercellular junctions in type-II VECs was abolished by “RGS5 overexpression” and “p38α MAPK inhibition”.

CONCLUSION: p38α MAPK plays crucial roles in “type-I vs type-II” phenotype regulations of human VECs at the downstream of RGS5.

New categorization of human vascular endothelial cells by pro- vs anti-proliferative phenotypes

AIM: To integrally understand the effects of human vascular endothelial cells (VECs) on the proliferation of vascular smooth muscle cells (VSMCs).

METHODS: Various kinds of human VECs of different origins were co-cultured with human aortic smooth muscle cells, a representative of human VSMCs. To exclude the irrelevant effects due to growth competition between VECs and VSMCs, the proliferation of VECs had previously been arrested via a low-dose gamma ray irradiation. To discriminately analyze the proliferation of VSMCs from that of VECs, the former cells were labeled with red fluorescent dye while the latter cells were labeled with green fluorescent dye before performing co-culture experiments. After 4 d, total cells were harvested and subjected to flow cytometric analyses. Decrements in red fluorescence intensities due to proliferation-mediated dilutions were measured and mathematically processed using a specific software to quantitatively evaluate the proliferation of VSMCs. The findings obtained from the flow cytometry-based analyses were further validated by microscopic observations.

RESULTS: Commercially available primary cultured human VECs exclusively promoted VSMC proliferation regardless of their tissue origins and we termed these pro-proliferative VECs as “type-I”. By contrast, VECs freshly generated from human bone marrow-derived endothelial progenitors cells or human pluripotent stem cells including embryonic stem cells and induced pluripotent stem cells suppressed VSMC proliferation and we termed these anti-proliferative VECs as “type-II”. Repetitive subcultures as well as oxidative stress induced “type-II VECs to type-I” conversion along with an induction of Regulator of G-protein signaling 5 (RGS5). Compatibly, anti-oxidant treatments suppressed both the subculture-dependent “type-II to type-I” conversion and an induction of RGS5 gene. Immunostaining studies of clinical specimens indicated that RGS5 protein expressions in endothelial layers were low in normal arteries but they were up-regulated in pathological arteries including hypertension, atherosclerosis and autoimmune vasculitis in a dose-dependent manner. Overexpression and knockdown of RGS5 caused that “type-II to type-I” and “type-I to type-II” phenotype conversions of VECs, respectively.

CONCLUSION: Human VECs are categorized into two types: pro-proliferative RGS5^high VECs (type-I) and anti-proliferative RGS5^low VECs (type-II).

Photobiomodulation therapy for osteoarthritis: Mechanisms of action

Photobiomodulation (PBM) is a non-invasive therapeutic modality with demonstrated effects in many fields related to regenerative medicine. In the field of orthopedics, in particular, PBM at various wavelengths has demonstrated the capacity to trigger multiple biological effects associated with protective mechanisms in musculoskeletal tissues. The articles cited in this review show that devices operating close to or within the near infrared range at low intensities can provoke responses which favor the shift in the predominant catabolic microenvironment typically seen in degenerative joint diseases, especially osteoarthritis (OA). These responses include proliferation, differentiation and expression of proteins associated with stable cell cycles. Additionally, PBM can also modulate oxidative stress, inflammation and pain by exerting regulatory effects on immune cells and blocking the transmission of pain through sensory neuron fibers, without adverse events. Collectively, these effects are essential in order to control the progression of OA, which is in part attributed to exacerbated inflammation and degradative enzymatic reactions which gradually contribute to the destruction of joint tissues. PBM may offer medical experts ease of application, financial viability, efficacy and lack of serious adverse events. Therefore, it may prove to be a suitable ally in the management of mild to moderate degrees of OA. This review explores and discusses the principal biological mechanisms of PBM and how the produced effects may contribute to the amelioration of osteoarthritic progression. Literature was reviewed using PubMed and Google Scholar in order to find studies describing the mechanisms of PBM. The investigation included a combination of nomenclature such as: “photobiomodulation”, “phototherapy”, “laser therapy”, “PBM”, “osteoarthritis”, low level light therapy”, “inflammation” and “cartilage”. We considered only articles written in English, with access to the full text.

High-potency sucralfate prevents and rapidly reverses chemo-radiation mucositis in a patient with stage 4b head and neck cancer

AIM: To study usefulness of high-potency sucralfate (HPS) in a patient with chemoradiation mucositis and discuss its mechanism of action.

METHODS: HPS, a non-covalently cross-link of sucralfate, cations and bidentate anionic chelators, has a maintains a surface concentration of sucralfate 3 h following administration that is 7-23 fold that possible with standard-potency sucralfate. The accelerated mucosal healing and pain alleviation of HPS in patients with erosive esophageal reflux, prompted its use in this patient with chemoradiation mucositis of the oropharynx and alimentary tract. A literature-based review of the immuno-modulatory effects of sucralfate is discussed.

RESULTS: Within 48 h of intervention: (1) there was complete disappearance of oral mucositis lesions; tenderness with (2) patient-reported disappearance of pain, nausea and diarrhea; patient required (3) no opiate analgesia and (4) no tube-feeding supplements to regular diet. Dysgeusia and xerostomia persisted. A modified Naranjo Questionnaire score of 10 supported the likelihood that HPS intervention caused the observed clinical effects. No adverse reactions noted.

CONCLUSION: In this patient HPS was useful to treat chemo-radiation mucositis of the oropharynx and alimentary tract. HPS may directly or indirectly facilitate an immunomodulatory mechanism involving accelerated growth factor activation, which may be a new target for therapeutic intervention in such patients.

Effects of USPSTF guidelines on patterns of screening and treatment outcomes for prostate cancer

The updated United States Preventive Services Task Force (USPSTF) for prostate cancer in 2012 recommends against prostate-specific antigen (PSA) based screening for men of all ages. Prostate cancer is the second most common and second most deadly cancer in American men. PSA screening for prostate cancer has been present since 1994 leading to an over diagnosis and over treatment of low volume disease. There is an overall agreement of men towards the guidelines but even with the understanding of the USPSTF, these men tend to follow more personal beliefs that have been influenced by their knowledge of the disease process and physician influence. Physicians also followed the directions of the patients and opted not to change their current practice of PSA screening despite the new guidelines. Time, legal, and ethical issues were some of the barriers that physicians faced in tailoring their practice towards screening. The importance of informed consent is highlighted by both the patients and the physicians and clearly more effective when the patient was pre-informed of the disease process and prompted the physicians to initiate conversation of informed screening. Younger patients were inclined towards aggressive treatment and older patients opted towards watchful waiting both with emphasis on the importance of evidence-based information provided by the physician. Decision aids were useful in making informed decisions and could be used to educate patients on screening purposes and treatment options. However, even with well-created decision aids and physician influence, patients’ own belief system played a major part in healthcare decision making in either screening or treatment for prostate cancer.

Recent advances and perspectives on tropical diseases: Malaria

Malaria remains a major health problem in the world. It is a neglected disease because it occurs almost exclusively in poor developing countries, which offer negligible marketable and profitable opportunities. Malaria (together with Tuberculosis), is responsible for an unprecedented global health crisis with devastating effects in developing countries. The 2011 Word Malaria Report indicated that 106 countries showed endemic malaria. Malaria control depends mainly on drug treatment, which is increasingly difficult due to the spread of drug resistant parasites and requires expensive drug combinations. Part of the inability to combat this disease is attributed to an incomplete understanding of its pathogenesis and pathophysiology. Improving the knowledge of the underlying pathogenic mechanisms of malaria transmission and of the exclusive metabolic pathways of the parasites (protozoa of the genus Plasmodium), should promote efficient treatment of disease and help the identification of novel targets for potential therapeutic interventions. Moreover, the elucidation of determinants involved in the spread of malaria will provide important information for efficient planning of strategies for targeted control.

Examining the relationship between physical fitness and spiritual fitness in cancer patients: A pilot study

AIM: To examine the relationship between spiritual fitness and overall physical fitness, and their resulting impact on feelings of depression and anxiety in individuals being treated for cancer.

METHODS: Thirty patients completed the McGill Quality of Life questionnaire and the Spiritual Fitness Assessment survey, and were asked to classify themselves as “Religious” or “Non-Religious”. After the questionnaires were completed, each patient underwent a comprehensive fitness assessment, which included assessments for VO_2max, muscular strength and endurance, flexibility, and body composition, as well as height, weight, and resting heart rate and blood pressure. The data collected were averaged and analyzed using a one-way ANOVA test at the 0.05 level of significance.

RESULTS: Of the 30 participants, 17 classified themselves as “religious” (R) and 13 classified themselves as “non-religious” (NR). The R group had a higher body fat percentage and a lower VO_2max than the NR group. However, these results were not significant. It was also determined that the R group scored themselves significantly higher than the NR group on the Spiritual Fitness questionnaire, but reported significantly higher levels of depression and anxiety than their non-religious counterparts.

CONCLUSION: Health beliefs did not necessarily back up health practice; specifically, those respondents who classified themselves as “religious” reported that their beliefs positively influenced their health behaviors, yet physiological and psychological data did not support this claim.

Physics and mathematics of magnetic resonance imaging for nanomedicine: An overview

Magnetic resonance imaging (MRI), magnetic resonance angiography (MRA) and magnetic resonance spectroscopy (MRS) are fundamental concepts used in modern medicine to improve health care. These concepts are based on the principle of nuclear magnetic resonance (NMR). Over the years, various laboratories around the world have applied different numerical techniques based on the Bloch NMR equations to solve specific problems in physics, biology, chemistry, engineering and medicine. The ultimate goal of any physician is to obtain maximum physical, biophysical, chemical and biological information on any tissue or cell under examination. This goal can be achieved by solving the Bloch NMR flow equations analytically. In this review, we present the basic principle of NMR/MRI in a way that can be easily understood by any researcher who needs an NMR concept to solve a specific medical problems. After a very brief history of the subject, a second order, non homogeneous, time-dependent differential equation derived from the Bloch NMR equation is presented. This equation has the basic intrinsic properties of MRI, MRA and MRS that can be extracted by means of classical and quantum mechanics for possible application in nanomedicine.

Translational medical mycology guides clinical and laboratory practice on fungal diseases

Patients with fungal infection having skin lesions may consult a dermatologist, which is a diagnostic and therapeutic challenge. Dermatologists take samples from the lesion to check the fungal elements under a microscope by KOH preparation and then treat the patient. This model has advanced from bedside to bench and from bench to bedside (B to B to B), which is defined as Translational Medical Mycology. Dermatologists have an advantageous position in finding, isolating and identifying the pathogenic fungi and treating the patient with antifungal drugs. Samples should be cultured in different media with or without chloramphenicol and cycloheximide and incubated at room temperature or 37 °C. Non-culture techniques such as polymerase chain reaction based molecular identification, transmission electron microscopy, scanning electron microscopy, biochemistry tests and histopathology are also necessary to confirm the identification of the species, especially when the routine culture is negative. We start treatment upon obtaining evidence of fungal infection, i.e., positive KOH examination. Antifungal drugs such as itraconazole, fluconazole, terbinafine and amphotericin B can be used alone or in combination based on the fungal species and the location of the lesion. Practice on fungal infection includes screening of the patient, merging all of the laboratory techniques and methods from the microbiologists, pathologists, molecular researchers, identification of the pathogen and determination of the optimum antifungal drug.

Beyond the bedside: A review of translational medicine in global health

Translational research is a broad field of medicine with several key phases moving from scientific discovery to bench research and the hospital bedside, followed by evidence-based practice and population-level policy and programming. Understanding these phases is crucial when it comes to preventing and treating illness, especially in global health. Communities around the world struggle with a variety of health problems that are at some times similar and at others quite different. Three major world health issues help to outline the phases of translational research: vaccines, human immunodeficiency virus and acquired immunodeficiency syndrome, and non-communicable diseases. Laboratory research has excelled in many of these areas and is struggling in a few. Where successful therapies have been discovered there are often problems with appropriate use or dissemination to groups in need. Also, many diseases would be better prevented from a population health approach. This review highlights successes and struggles in the arena of global health, from smallpox eradication to the impending epidemic of cardiovascular disease, in an attempt to illustrate of the various phases of translational research.

Pathophysiological responses from human gut microbiome

The human gastrointestinal tract harbors a vast collection of symbiotic microorganisms-collectively termed as “gut microbiome”. This microbiota has important effect in immune system and other host activities. Recent studies have suggested that alterations of the normal gut microbiota are associated with various human diseases and psychological disorders. The underlying cause, once proven, may provide novel insights into the importance of gut flora in human health. In this review, we give an attempt to describe how the alteration in the microbial community causes the development of certain widespread pathophysiological disorders; focusing on inflammatory bowel disease, colorectal cancer, obesity and autism. Proper knowledge about the host-microbiota interaction and linkage could be essential for the development of future personalized strategies of therapeutics.

Obesity research: Status quo and future outlooks

Obesity is a multifactorial disease showing a pandemic increase within the last decades in developing, and developed countries. It is associated with several severe comorbidities such as type II diabetes, hypertension, sleep apnea, non-alcoholic steatosis hepatis and cancer. Due to the increasing number of overweight individuals worldwide, research in the field of obesity has become more vital than ever. Currently, great efforts are spend to understand this complex disease from a biological, psychological and sociological angle. Further insights of obesity research come from bariatric surgery that provides new information regarding hormonal changes during weight loss. The initiation of programs for obesity treatment, both interventional and pharmaceutical, are being pursued with the fullest intensity. Currently, bariatric surgery is the most effective therapy for weight loss and resolution of comorbidities in morbid obese patients. Reasons for weight loss and remission of comorbidities following Roux-en-Y-Gastric Bypass, Sleeve Gastrectomy, and other bariatric procedures are therefore under intense investigation. In this review, however, we will focus on obesity treatment, highlighting new insights and future trends of gut hormone research, the relation of obesity and cancer development via the obesity induced chronic state of inflammation, and new potential concepts of interventional and conservative obesity treatment.

Peptide-based boronates: How to achieve tissue specificity in anticancer therapy

Dipeptidyl boronic acids are suitable candidates for the design of “pro-soft” drugs because recent studies have proven that these acids undergo a pH-dependent cyclization equilibrium, generating an inactive cyclic form under physiological conditions. Dipeptidyl boronic acids possess a wide range of potential targets, and the 26S proteasome appears to be one of the main targets. This multicatalytic complex is involved in intracellular protein turnover and is overexpressed in certain pathological conditions, such as malignancies, autoimmune diseases and neurodegenerative diseases. Bortezomib is the first-in-class derivative approved by the Food and Drug Administration for the treatment of hematological malignancies (i.e., relapsed and refractory multiple myeloma and mantle cell lymphoma) but is inactive against solid tumors due to an insufficient tissue distribution. The present study suggests a possible strategy for enhancing the in vivo performance of dipeptidyl boronic acids endowed with promising proteasome-inhibiting properties and their applicability as anticancer agents. In particular, dipeptidyl boronic acids might have a fruitful application as pro-soft drugs when an appropriate recognition motif serves as a substrate for a tumor-specific protease, generating the active form of the drug in situ and preventing systemic side effects after diffusion through cells and tissues.

Targeting apoptosis is the major battle field for killing cancers

Targeting apoptosis is one of the major strategies for cancer therapy. Essentially, most of the conventional cancer therapeutic drugs that are in the clinical use induce apoptosis and in part necrosis of malignant cells and therefore prevent cancer progression and metastasis. Although these cytotoxic anticancer drugs are important weapons for killing cancers, their toxic side effects limited their application. The molecularly targeted therapeutics that are based on the deeper understanding of the defects in the apoptotic signaling in cancers are emerging and have shown promising anticancer activity in selectively killing cancers but not normal cells. The examples of molecular targets that are under exploration for cancer therapy include the cell surface receptors such as TNFR family death receptors, the intrinsic Bcl-2 family members and some other intracellular molecules like p53, MDM2, IAP, and Smac. The advance in the high-throughput bio-technologies has greatly accelerated the progress of cancer drug discovery.