Enhanced antitumor activity induced by a DNA vaccine encoding E7 antigen fused to an ERAD-targeting sequence.

The endoplasmic reticulum (ER) is a key organelle in cell homeostasis and cell health through antigen presentation to immune cells. Thus, the ER has become a therapeutic target to induce cellular immune responses. We previously reported the antitumor effect of a DNA vaccine that expresses the E7 antigen fused to the cyclooxygenase-2 (COX-2) protein. This inflammation-related enzyme contains a degradation cassette associated with the endoplasmic reticulum-associated degradation (ERAD) pathway. To avoid the use of full-length COX-2 and any risk of adverse effects due to the activity of its catalytic site, we designed new versions of the fusion protein. These new constructs encode the E7 antigen fused to the signal peptide and the ERAD sequence of COX-2 with or without the membrane-binding domain (MBD) as well as deletion of the catalytic site. We evaluated the antigen-specific antitumor effect of these DNA constructs in murine prophylactic and therapeutic cancer models. These assays showed that the ERAD cassette is the minimum sequence in the COX-2 protein that induces an antitumor effect when fused to the E7 antigen with the advantage of eliminating any potential adverse effects from the use of full-length COX-2.

Chronic diseases: Origin and cell mechanisms involved.

Chronic diseases are a worldwide health problem directly related to society, lifestyle, and the development of unhealthy habits over time. Cardiovascular disease, cancer, chronic respiratory disease, and diabetes are the main causes of death. Environmental factors, such as air pollutants, poor diet, genetic predisposition, or a combination of these, are related to the development of these diseases. These factors activate cell mechanisms, such as DNA damage, oxidative stress, endoplasmic reticulum stress, autophagy, inflammation, and cell death. Depending on the dose and duration of exposure to causative agents, this cell damage can be acute or chronic. Activating these cell mechanisms can rescue normal cell function and cause permanent damage, unleashing the degeneration of tissues and organs over time. A wide variety of treatments help control chronic diseases; however, they cannot be cured completely. This fact leads to complications, dysfunctions, and disabilities. Herein, we discuss some of the principal mechanisms involved and how cellular stress can lead to these diseases when they persist for a long time.

Cerebrolysin induces hair repigmentation associated to MART-1/Melan-A reactivation.

Hair graying, a prototypical sign of human aging, is a progressive loss of pigmentation from growing hair shafts caused by disease and as a side effect of medications. Cerebrolysin is a neuropeptide preparation that mimics the effect of endogenous neurotrophic factors. Cerebrolysin has been widely used in neurologic conditions, such as cerebral stroke, Alzheimer's disease, and dementia, among others. Cerebrolysin treatment has achieved to regain or maintain the cognitive ability of affected patients; however, up to date, there are no reports about the reactivation of hair pigmentation. We describe a previously not described effect occurring on patients receiving Cerebrolysin treatment for neurologic diseases and whether this effect is associated in reactivation of melanocytes and melanin expression. Here, we report five patients (mean age, 70.6 years), who also had age-related hair graying and scalp hair repigmentation during Cerebrolysin treatment. Macroscopic analysis revealed hair repigmentation consisted in diffuse darkening of the scalp hair. Impregnation and immunostaining analysis were performed on scalp biopsies taken before and after Cerebrolysin treatment; the results showed greater melanin and melanocyte marker MART-1/Melan-A staining following Cerebrolysin treatment. We present, to our knowledge, the first report on hair repigmentation is a previously not described effect occurring following Cerebrolysin treatment.

Plasmid DNA for Therapeutic Applications in Cancer.

Recently, the interest in using nucleic acids for therapeutic applications has been increasing. DNA molecules can be manipulated to express a gene of interest for gene therapy applications or vaccine development. Plasmid DNA can be developed to treat different diseases, such as infections and cancer. In most cancers, the immune system is limited or suppressed, allowing cancer cells to grow. DNA vaccination has demonstrated its capacity to stimulate the immune system to fight against cancer cells. Furthermore, plasmids for cancer gene therapy can direct the expression of proteins with different functions, such as enzymes, toxins, and cytotoxic or proapoptotic proteins, to directly kill cancer cells. The progress and promising results reported in animal models in recent years have led to interesting clinical results. These DNA strategies are expected to be approved for cancer treatment in the near future. This review discusses the main strategies, challenges, and future perspectives of using plasmid DNA for cancer treatment.

Effect of Diameter and Fenestration Area of the Liposuction Cannula on the Viability of the Adipocytes.

BACKGROUND: Loss of volume is perhaps the most frustrating problem of fat grafting. The process of fat grafting depends on different variables such as harvesting, processing, and injection techniques. Results between studies that evaluate the effect of the cannula size on fat graft survival have been controversial. However, the role of the fenestration area of the cannula has not been described. METHODS: Four custom-made cannulas with a single fenestration were used for this study. Cannulas vary in diameter and area of the fenestration. Healthy patients seeking primary liposuction of the abdomen for aesthetic reasons were included. Lipoaspiration was performed in a clockwise pattern, and the order of the cannulas was rotated. Negative pressure was maintained at 0.8 atm at all times. Ten ml of fat, obtained from the suction tube, was poured into 20-ml conical centrifugal tubes for further processing. One gram of lipoaspirate was extracted from each sample, and acridine orange stain was added. Adipocytes were extracted, extended in a frotis, and observed by a histologist (masked fashion) under fluorescence microscopy. Viability was reported in percentages per sample. RESULTS: The overall viability was 64.75% ± 18.58. The viability of the obtained samples ranged from 66.51± 20.66 % to 62.83 ± 18.1. In further analysis, comparing the viability according to the shaft diameter and fenestration area, there was no significant difference among groups. CONCLUSIONS: Neither the diameter of the cannula nor the size of the fenestrations are determining factors to affect the viability of the adipocytes. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Targeting E7 antigen to the endoplasmic reticulum degradation pathway promotes a potent therapeutic antitumor effect.

It has been previously reported that targeting and retaining antigens in the endoplasmic reticulum (ER) can induce an ER stress response. In this study, we evaluated the antitumor effect of E7 antigen fused to an ERresident protein, cyclooxygenase-2, which possesses a 19-aminoacid cassette that directs it to the endoplasmic reticulum-associated protein degradation (ERAD) pathway. The featured DNA constructs, COX2-E7 and COX2-E7ΔERAD, with a deletion in the 19-aminoacid cassette, were used to evaluate the importance of this sequence. In vitro analysis of protein expression and ER localisation were verified. We observed that both constructs induced an ER stress response. This finding correlated with the antitumor effect in mice injected with TC-1 cells and treated with different DNA constructs by biolistic vaccination. Immunisation with COX2-E7 and COX2-E7ΔERAD DNA constructs induced a significant antitumor effect in mice, without a significant difference between them, although the COX2-E7 construct induced a significant E7-specific immune response. These results demonstrate that targeting the E7 antigen to the ERAD pathway promotes a potent therapeutic antitumor effect. This strategy could be useful for the design of other antigen-specific therapies.

Antitumor effect of adenoviruses expressing mutant non-oncogenic E7 versions from HPV-16 fused to calreticulin.

PURPOSE: To compare the antitumor effect of adenoviruses that express mutant variants of the protein E7 from HPV-16 fused to calreticulin. METHODS: Recombinant adenoviruses were generated to express calreticulin fused to mutant versions of E7 (CRT/E7m and CRT/E7dm). Western blot and immunofluorescence assays were made to demonstrate protein expression. Antitumor assays were performed in C57BL6 mice injected with TC-1 cell line. RESULTS: When HEK293 cells were infected with these adenoviruses, we detected that all the recombinant proteins were expressed at endoplasmic reticulum, as expected. Next, the antitumor effect was tested on a murine tumor model established by inoculation of TC-1 cell line. We detected that both Ad CRT/E7m and Ad CRT/E7dm were capable of reducing the antitumor volume when compared to Ad LacZ, which was used as negative control. No significant difference was observed when compared to Ad CRT/E7, a positive control. CONCLUSIONS: Here we demonstrated that the mutant versions of E7 HPV-16 fused to calreticulin generate similar antitumor effect than the wild type version.

Neurodegeneration, demyelination, and astrogliosis in rat spinal cord by chronic lead treatment.

Early exposure to lead (Pb) has been associated with an elevated risk of developing neurodegenerative diseases. There is evidence that neuronal damage in chronic Pb exposure can be caused by the convergence of glial damage. Apoptosis may be a possible mechanism of Pb-induced cell death in the central nervous system. We tested cellular damage and apoptosis in the spinal cord of Wistar rats treated with Pb. Twelve rats were divided into two groups (n = 6): the control group was treated with only drinking water and the other group received 500 ppm of Pb acetate. After 3 months of Pb treatment, all animals were euthanized and spinal cords were extracted. Morphology was evaluated by Nissl and Kluver-Barrera stainings. Apoptosis was detected by terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Specific antibodies were used to evaluate Pb damage in oligodendrocytes, astrocytes, and microglia. A large number of apoptotic bodies was observed in the white matter of the Pb-treated group. The Pb-treated group also showed a reduced number of neurons and oligodendrocytes but had an increased number of astrocytes compared with the nontreated group. Our results demonstrate that chronic Pb treatment induces neurodegeneration, demyelination, and astrogliosis in the rat spinal cord.