RKIP Inhibition in Cervical Cancer Is Associated with Higher Tumor Aggressive Behavior and Resistance to Cisplatin Therapy

Cervical cancer is one of the most common cancers in women worldwide, being high-risk group the HPV infected, the leading etiological factor. The raf kinase inhibitory protein (RKIP) has been associated with tumor progression and metastasis in several human neoplasms, however its role on cervical cancer is unclear. In the present study, 259 uterine cervix tissues, including cervicitis, cervical intraepithelial lesions and carcinomas, were analyzed for RKIP expression by immunohistochemistry. We found that RKIP expression was significantly decreased during malignant progression, being highly expressed in non-neoplastic tissues (54% of the samples; 73/135), and expressed at low levels in the cervix invasive carcinomas (∼15% (19/124). Following in vitro downregulation of RKIP, we observed a viability and proliferative advantage of RKIP-inhibited cells over time, which was associated with an altered cell cycle distribution and higher colony number in a colony formation assay. An in vitro wound healing assay showed that RKIP abrogation is associated with increased migratory capability. RKIP downregulation was also associated with an increased vascularization of the tumors in vivo using a CAM assay. Furthermore, RKIP inhibition induced cervical cancer cells apoptotic resistance to cisplatin treatment. In conclusion, we described that RKIP protein is significantly depleted during the malignant progression of cervical tumors. Despite the lack of association with patient clinical outcome, we demonstrate, in vitro and in vivo, that loss of RKIP expression can be one of the factors that are behind the aggressiveness, malignant progression and chemotherapy resistance of cervical cancer.     

Modulation of bone marrow mesenchymal stem cell secretome by ECM-like hydrogels

It has been demonstrated that bone marrow mesenchymal stem cell (BM-MSCs) transplantation has beneficial effects on several central nervous system (CNS) debilitating conditions. Growing evidence indicate that trophic factors secreted by these cells are the key mechanism by which they are acting. These cells are frequently used in combination with 3D artificial matrices, for instance hydrogels, in tissue engineering-based approaches. However, so far, no study has been reported on the influence of such matrices, namely the presence or absence of extracellular matrix motifs, on BM-MSCs secretome and its effects in neuronal cell populations. In this sense, we herein studied the impact of a hydrogel, gellan gum, on the behavior and secretome of BM-MSCs, both in its commercial available form (commonly used in tissue engineering) and in a fibronectin peptide-modified form. The results showed that in the presence of a peptide in the gellan gum hydrogel, BM-MSCs presented higher proliferation and metabolic activity than in the regular hydrogel. Moreover, the typical spindle shape morphology of BM-MSCs was only observed in the modified hydrogel. The effects of the secretome of BM-MSCs were also affected by the chemical nature of the extracellular matrix. BM-MSCs cultured in the modified hydrogel were able to secrete factors that induced higher metabolic viabilities and neuronal cell densities, when compared to those of the unmodified hydrogel. Thus adding a peptide sequence to the gellan gum had a significant effect on the morphology, activity, proliferation and secretome of BM-MSCs. These results highlight the importance of mimicking the extracellular matrix when BM-MSCs are cultured in hydrogels for CNS applications.     

Intermolecular interactions between DNA and methamphetamine,amphetamine, ecstasy and their major metabolites

In this work, we carried out a theoretical investigation regarding amphetamine-type stimulants, which can cause central nervous system degeneration, interacting with human DNA. These include amphetamine, methamphetamine, 3,4-Methylenedioxymethamphetamine (also known as ecstasy), as well as their main metabolites. The studies were performed through molecular docking and molecular dynamics simulations, where molecular interactions of the receptor–ligand systems, along with their physical–chemical energies, were reported. Our results show that 3,4-Methylenedioxymethamphetamine and 3,4-Dihydroxymethamphetamine (ecstasy) present considerable reactivity with the receptor (DNA), suggesting that these molecules may cause damage due to human-DNA. These results were indicated by free Gibbs change of bind (ΔG_bind) values referring to intermolecular interactions between the drugs and the minor grooves of DNA, which were predominant for all simulations. In addition, it was observed that 3,4-Dihydroxymethamphetamine (ΔG_bind = ?13.15 kcal/mol) presented greater spontaneity in establishing interactions with DNA in comparison to 3,4-Methylenedioxymethamphetamine (ΔG_bind = ?8.61 kcal/mol). Thus, according with the calculations performed our results suggest that the 3,4-Methylenedioxymethamphetamine and 3,4-Dihydroxymethamphetamine have greater probability to provide damage to human DNA fragments.     

Sex-dependent correlation between survival and expression of genes related to the circadian oscillator in patients with colorectal cancer

ABSTRACT

Recent evidence supports the important role of the circadian system in cancer progression in humans. The aim of the present study is to evaluate clock (cry1, cry2 and per2) and clock-controlled (vascular endothelial growth factor-a, early growth response protein 1 and estrogen receptor β) gene expression in colorectal cancer and adjacent tissue and identify a possible link between survival of patients and expression of above mentioned genes. The study includes 64 patients of both sexes with previously diagnosed colorectal cancer. RNA was extracted from the tumor tissue and adjacent parts of the resected colon, and real-time PCR was used for detection of clock gene expression. Expression of cry2 and per2 was significantly downregulated in tumor tissue compared to adjacent tissues. After splitting of the cohort according to sex, we detected downregulated levels of cry2 and per2 in male patients, but not in females. Splitting of male and female sub-cohorts according to presence of metastases revealed significant donwregulation of cry2 expression in female patients without distant metastasis. Better survival rate was associated with low expression of cry2 in female patients. Moreover, we observed an increase in cry1 expression in female patients with distant metastases in tumor compared to adjacent tissue. Accordingly, women with high expression of cry1 in tumor tissue displayed worse survival, which was not observed in men. Taken together, expression of clock and clock-controlled genes in tumors of males and females clustered according to presence of distant metastases correlated with survival analysis. Studied clock-controlled genes also showed sex-dependent changes. Low expression of vegf-a in tumor correlated with better survival in men but not in women. High expression of estrogen receptor β mRNA was related to better survival in women but not in men. Low expression of vegf-a, egr1 and estrogen receptor β was associated with worse survival in women compared to men. Our data indicate sex-dependent associations between clock and clock-controlled gene expression in cancer tissue and patient’s survival prognosis.     

Application of Hazard Analysis and Critical Control Points (HACCP) to the Cultivation Line of Mushroom and Other Cultivated Edible Fungi

The Hazard analysis and critical control points (HACCP) is a preventive system which seeks to ensure food safety and security. It allows product protection and correction of errors, improves the costs derived from quality defects and reduces the final overcontrol. In this paper, the system is applied to the line of cultivation of mushrooms and other edible cultivated fungi. From all stages of the process, only the reception of covering materials (stage 1) and compost (stage 3), the pre-fruiting and induction (step 6) and the harvest (stage 7) have been considered as critical control point (CCP). The main hazards found were the presence of unauthorized phytosanitary products or above the permitted dose (stages 6 and 7), and the presence of pathogenic bacteria (stages 1 and 3) and/or heavy metals (stage 3). The implementation of this knowledge will allow the self-control of their productions based on the system HACCP to any plant dedicated to mushroom or other edible fungi cultivation.     

Serologic survey of West Nile virus in horses from Central-West,Northeast and Southeast Brazil

Since the emergence of West Nile virus (WNV) in North America in 1999, there have been several reports of WNV activity in Central and South American countries. To detect WNV in Brazil, we performed a serological survey of horses from different regions of Brazil using recombinant peptides from domain III of WNV. Positive samples were validated with the neutralisation test. Our results showed that of 79 ELISA-positive horses, nine expressed WNV-specific neutralising antibodies. Eight of the infected horses were from the state of Mato Grosso do Sul and one was from the state of Paraíba. Our results provide additional evidence for the emergence of WNV in Brazil and for its circulation in multiple regions of the country.