Mirela Cioplea

Variations in the expression of TIMP1, TIMP2 and TIMP3 in cutaneous melanoma with regression and their possible function as prognostic predictors

Regression in melanoma is a frequent biological event of uncertain prognostic value as the lesion exhibits heterogeneous phenotypical features, both at the morphological and immunohistochemical level. In the present study, we examined the expression of tissue inhibitors of metalloproteinases (TIMP1, TIMP2 and TIMP3) in melanoma with regression. We specifically examined the expression levels of these TIMPs in regressed components (RC) and non-regressed components (NRC) of the tumor and compared their expression levels with those in non-regressed melanomas. We found that TIMP1 was overexpressed in the NRC of melanomas with partial regression (PR) compared with the NRC in melanomas with segmental regression (SR) (P=0.011). TIMP2 was overexpressed in the NRC of melanomas with PR compared with the NRC in melanomas with SR (PR/SR, P=0.009); or compared with the NRC in melanomas with simultaneous SR-PR (P=0.002); or compared with melanomas without regression (absence of regression) (P=0.037). Moreover, TIMP3 was overexpressed in the NRC of all melanomas with SR as compared to the RC component (P=0.007). Our findings on the differential expression of TIMP1, TIMP2 and TIMP3 in melanomas with regression support the hypothesis that the morphological differences identified in the melanoma regression spectrum may have a correlation with prognosis. This may explain the controversial findings within the literature concerning the biological and prognostic role of regression in melanoma.

Expression Profile of p53 and p21 in Large Bowel Mucosa as Biomarkers of Inflammatory-Related Carcinogenesis in Ulcerative Colitis

Ulcerative colitis (UC) is a chronic, relapsing inflammatory bowel disease that slightly increases the risk of colorectal cancer in patients with long-standing extended disease. Overexpression of p53 and p21 in colonic epithelia is usually detected in UC patients when no dysplasia is histologically seen and it is used by pathologists as a discriminator between regenerative changes and intraepithelial neoplasia, as well as a tissue biomarker useful to predict the risk of evolution toward malignancy. We present a one-year prospective observational study including a cohort of 45 patients with UC; p53 and p21 were evaluated in epithelial cells. p53 was positive in 74 samples revealed in 5% to 90% of epithelial cells, while 63 biopsies had strong positivity for p21 in 5% to 50% of epithelial cells. Architectural distortion was significantly correlated with p53 overexpression in epithelial cells. Thus, we consider that architectural distortion is a good substitute for p53 and p21 expression. We recommend use of p53 as the most valuable tissue biomarker in surveillance of UC patients, identifying the patients with higher risk for dysplasia. Association of p21 is also recommended for a better quantification of risk and for diminishing the false-negative results.

Innovative array-based assay for omics pattern in melanoma

ABSTRACT Cutaneous melanoma remains a major health issue and still an important challenge for research. Thus, omics complex evaluation can provide a more specific molecular classification for this heterogeneous disease. Complex omics analysis based on genomic and proteomic microarrays can identify disease markers that prognosticate disease evolution or can monitor therapies efficacy. Among the technologies that gained momentum in the last years, array-based comparative genomic hybridization offered the possibility to analyze chromosomal numerical aberrations within cutaneous melanomas providing important support for molecular classification of melanoma tumors. This technology can identify new chromosomal alterations and discover new deregulated melanoma genes that can be further used as therapy targets. Integrating genetic profiling with clinical and pathological parameters would lead to seminal improvements in diagnosis, prognosis, and therapy.

Caspases, Cell Death and Diabetic Nephropathy.

Abstract Diabetic Nephropathy. In 2014 (according to data published by the World Health Organization) 9% of the global population was affected by Diabetes which was considered to be directly responsible for 1.5 million deaths just two years prior (in 2012). From the entire number of patients suffering from diabetes, approximately a quarter of them develop renal affection. Diabetic nephropathy has similar physiopathology mechanisms and ultrastructural changes in cell injury characteristics in both Type 1 and Type 2 diabetes. Cell Death. Cell Death was less studied in the renal diabetic disease, although it could represent an important pathogenic mechanism in the appearance and progression of nephropathy. At renal level the cellular loss can be explained by several mechanisms; different stimuli with cellular lesion potential can trigger apoptosis signaling with appearance of regulatory proteins having a double role (they participate in the initiation of the apoptosis path and cell death or in the ending of this process). The types of Cell Death and their relative proportion between themselves in the renal tissue have not been completely elucidated. Caspases. Discovered in the middle of the 1990’s, Caspases are a part of the cysteine proteases family and play a role in numerous aspects of physiology (having a role in development, aging and apoptosis), but also in aspects of physiopathology of several degenerative affections, autoimmune diseases, oncologic diseases – having an important part in apoptosis, necrosis and also inflammation.

Neuroimmune cross-talk in Helicobacter pylori infection: analysis of substance P and vasoactive intestinal peptide expression in gastric enteric nervous system

ABSTRACT It is suggested that different neuropeptides are actively involved in the pathogenesis of Helicobacter pylori (H. pylori)-induced gastritis acting as important effectors of the neuroimmune complex interactions, but the available data is limited and contradictory. The aim of this study was to determine whether the chronic infection generates changes in substance P (SP) and vasoactive intestinal peptide (VIP) gastric level and to evaluate the dependence of these potential effects on the degree of bacterial colonization or the severity of the inflammatory infiltrate. Therefore, immunohistochemical tests were performed to examine SP and VIP expression in mucosal nerve endings and myenteric neurons. Both SP and VIP levels were significantly higher in gastric samples of patients infected with H. pylori compared to uninfected individuals, confirming that these neuropeptides are neuroimmune modulators involved in the pathogenesis of H. pylori infection. Although their expression did not correlate with the intensity of mucosal inflammation nor with the bacterial density, we observed a strong association between SP neuronal level and the degree of myenteric ganglionitis, which in turn correlated with the severity of mucosal T-cell infiltration. These findings suggest that the mechanisms of neuroimmune cross-talk depend on some other factors that remain to be determined.

Inflammatory-Driven Angiogenesis in Bone Augmentation with Bovine Hydroxyapatite, B-Tricalcium Phosphate, and Bioglasses: A Comparative Study

Introduction The clinical use of bioactive materials for bone augmentation has remained a challenge because of predictability and effectiveness concerns, as well as increased costs. The purpose of this study was to analyse the ability to integrate bone substitutes by evaluating the immunohistochemical expression of the platelet endothelial cell adhesion molecules, vascular endothelial growth factor, collagen IV, laminin, and osteonectin, in the vicinity of bone grafts, enabling tissue revascularization and appearance of bone lamellae. There is a lack of in vivo studies of inflammatory-driven angiogenesis in bone engineering using various grafts. Methods The study was performed in animal experimental model on the standardized monocortical defects in the tibia of 20 New Zealand rabbits. The defects were augmented with three types of bone substituents. The used bone substituents were beta-tricalcium phosphate, bovine hydroxyapatite, and bioactive glasses. After a period of 6 months, bone fragments were harvested for histopathologic examination. Endothelial cell analysis was done by analysing vascularization with PECAM/CD31 and VEGF and fibrosis with collagen IV, laminin, and osteonectin stains. Statistical analysis was realized by descriptive analysis which was completed with the kurtosis and skewness as well as the Kruskal-Wallis and Mann-Whitney statistical tests. Results The discoveries show that the amount of bone that is formed around beta-tricalcium phosphate and bovine hydroxyapatite is clearly superior to the bioactive glasses. Both the lumen diameter and the number of vessels were slightly increased in favor of beta-tricalcium phosphate. Conclusion We can conclude that bone substitutes as bovine bone and beta-tricalcium phosphate have significant increased angiogenesis (and subsequent improved osteogenesis) compared to the bioactive glass. In our study, significant angiogenesis is linked with a greater tissue formation, indicating that in bone engineering with the allografts we used, inflammation has more benefic effects, the catabolic action being exceeded by the tissue formation.

Immunohistochemical Aspects of Cell Death in Diabetic Nephropathy.

Introduction. Diabetes Mellitus causes ultrastructural changes triggered by partially clarified cellular mechanisms. Since cell death is an important mechanism in the appearance and progression of diabetic nephropathy, we studied alteration of several markers of apoptotic pathways signaling in renal tissue of diabetic or prediabetic patients. Methods. We analyzed 48 human kidney tissue samples divided into two study groups: the research group (43 renal tissue samples from diabetic or prediabetic patients), and the control group (5 renal tissue samples from patients without diabetes). Immunohistochemistry revealed expression of Bcl-2, APAF-1, CD-95 and Caspase-9 in the renal cortical structures. Statistical analysis was also performed (significance level P<0.05). Results. We found a variable expression of the antiapoptotic Bcl-2 with a decrease of Bcl-2 expression in diabetes. The control samples render evident intensely positive immunostaining for CD-95. In diabetes and diabetic nephropathy, there was positive immunostaining for APAF-1 at tubular cell level. Nuclear and cytoplasmic positivity for Caspase-9 was more frequently recorded as kidney damage progresses. APAF-1 and Caspase-9 positivity are arguments for an intrinsic apoptotic mechanism of cell death in diabetic nephropathy. Conclusion. The mechanisms of apoptotic cell death identified in diabetic kidney samples prove that Bcl-2, CD-95, APAF-1 and Caspase-9 represent reliable markers of cell death in human renal tissue. Our results support the hypothesis that apoptosis is a pathogenic and initiator mechanism of renal remodeling in diabetic kidney disease.

CEACAM1: Expression and Role in Melanocyte Transformation.

Metastases represent the main cause of death in melanoma patients. Despite the current optimized targeted therapy or immune checkpoint inhibitors the treatment of metastatic melanoma is unsatisfactory. Because of the poor prognosis of advanced melanoma there is an urgent need to identify new biomarkers to differentiate melanoma cells from normal melanocytes, to stratify patients according to their risk, and to identify subgroups of patients that require close follow-up or more aggressive therapy. Furthermore, melanoma progression has been associated with the dysregulation of cell adhesion molecules. We have reviewed the literature and have discussed the important role of the expression of the carcinoembryonic antigen cell adhesion molecule 1 (CEACAM1) in the development of melanoma. Thus, novel insights into CEACAM1 may lead to promising strategies in melanoma treatment, in monitoring melanoma patients, in assessing the response to immunotherapy, and in completing the standard immunohistochemical panel used in melanoma examination.