Implementation of a microwave-assisted tissue-processing system and an automated embedding system for breast needle core biopsy samples: morphology, immunohistochemistry, and FISH evaluation.

A platform composed of a microwave (MW)-assisted tissue-processing system and an automated embedding system has been recently introduced in pathology laboratories. Needle core biopsy (NCB) is an established, highly accurate method for diagnosing breast lesions and for providing important pathologic, predictive, and prognostic information such as biomarker expression in case of breast carcinoma. The aim of this study was to evaluate whether breast NCBs processed with the MW-assisted tissue-processing system and automatically embedded show good-quality histology preparations and whether they are suitable for the assessment of estrogen receptor (ER), progesterone receptor (PR), Ki-67, and HER2 in breast carcinoma.

Dental pulp stem cells differentiation reveals new insights in Oct4A dynamics.

Although the role played by the core transcription factor network, which includes c-Myc, Klf4, Nanog, and Oct4, in the maintenance of embryonic stem cell (ES) pluripotency and in the reprogramming of adult cells is well established, its persistence and function in adult stem cells are still debated. To verify its persistence and clarify the role played by these molecules in adult stem cell function, we investigated the expression pattern of embryonic and adult stem cell markers in undifferentiated and fully differentiated dental pulp stem cells (DPSC). A particular attention was devoted to the expression pattern and intracellular localization of the stemness-associated isoform A of Oct4 (Oct4A).

Acellular bone colonization and aggregate culture conditions diversely influence murine periosteum mesenchymal stem cell differentiation potential in long-term in vitro osteoinductive conditions.

Periosteum contains mesenchymal stem cells (Pe-MSCs) that contribute to normal bone growth, healing, and turnover; understanding Pe-MSC capabilities may shed light over the treatment of bone defects using tissue engineering. Bone tissue regeneration needs in vitro bone precursors or stem cell coculture onto specific scaffolds but, despite extensive research in the field, very little is known about the matrix structure of the tissue-engineered tissues and the scaffold's effects on cell differentiation. To this purpose we have selected a clonal population (murine Pe-MSCs) that was seeded and differentiated onto an acellular bone scaffold.

Histone deacetylase inhibitors induce thymidine phosphorylase expression in cultured breast cancer cell lines.

Thymidine phosphorylase (TP) is an enzyme involved in thymidine synthesis and degradation. The expression of this enzyme has been proposed as a predictive factor for the therapeutic benefit of capecitabine, which is a precursor of the drug 5'-fluorouracil. In fact, TP is the rate-limiting enzyme in the activation of capecitabine.

Adipose tissue-derived stem cell in vitro differentiation in a three-dimensional dental bud structure.

Tooth morphogenesis requires sequential and reciprocal interactions between the cranial neural crest-derived mesenchymal cells and the stomadial epithelium, which regulate tooth morphogenesis and differentiation. We show how mesenchyme-derived single stem cell populations can be induced to transdifferentiate in vitro in a structure similar to a dental bud. The presence of stem cells in the adipose tissue has been previously reported.

Biochemical and biophysical analyses of tissue-engineered bone obtained from three-dimensional culture of a subset of bone marrow mesenchymal stem cells.

Grafts of tissue-engineered bone represent a promising alternative in the treatment of large and small bone defects. Current approaches are often badly tolerated by patients because of invasiveness, ethical problems, culture, and possibility of infection. Autologous grafts have been indicated as a solution to such problems.

Multipotent progenitor cells are present in human peripheral blood.

To determine whether the peripheral blood in humans contains a population of multipotent progenitor cells (MPCs), products of leukapheresis were obtained from healthy donor volunteers following the administration of granulocyte colony-stimulating factor. Small clusters of adherent proliferating cells were collected, and these cells continued to divide up to 40 population doublings without reaching replicative senescence and growth arrest. MPCs were positive for the transcription factors Nanog, Oct3/4, Sox2, c-Myc, and Klf4 and expressed several antigens characteristic of mesenchymal stem cells.

Down-regulation of SM22/transgelin gene expression during H9c2 cells differentiation.

The embryonic rat ventricle H9c2 cells maintain a proliferative state (P condition) in the presence of 10% FCS. However, by reducing serum concentration and in the presence of retinol acetate, proliferation is stopped, myogenic transdifferentiation is inhibited while cardiac differentiation is preserved (D condition). Two-dimensional gel electrophoresis and mass spectrometry analysis was used to define the modifications of the nuclear proteome occurring during the P-to-D transition.

Prohibitin is overexpressed in papillary thyroid carcinomas bearing the BRAF(V600E) mutation.

Background: Prohibitin (PHB) is a multifunctional protein that is localized in different intracellular sites. PHB may exert different roles in tumorigenesis, having either a permissive action on tumor growth or an oncosuppressor role, depending on the cellular context. The objective of this study was to evaluate PHB expression in normal thyroid tissues, thyroid follicular adenomas (FAs), and papillary thyroid carcinomas (PTCs).

A web-based system for tissue microarray data management.

Background: Tissue Microarray is a novel technique for analysing large amounts of immunohistochemically stained specimens. However, those large amounts make it difficult to design, prepare and analyze a tissue microarray, so that software support is almost inevitable.

Methods: We designed a tissue microarray data management system starting from specifications obtained by pathologists, and arranged for a preliminary validation in thyroid pathology.

PAX8 expression in human bladder cancer.

PAX8 is a transcription factor with a role in ontogenesis of the urinary tract. The aim of the present investigation was to investigate PAX8 expression in normal bladder and in non-invasive urothelial tumours. Nine cases of normal urothelial mucosa, 2 cases of papillary urothelial neoplasia of low malignant potential, 12 cases of low grade non-invasive papillary urothelial carcinoma and 16 cases of high grade non-invasive papillary urothelial carcinoma were investigated by immunohistochemistry.

HEX expression and localization in normal mammary gland and breast carcinoma.

Background: The homeobox gene HEX is expressed in several cell types during different phases of animal development. It encodes for a protein localized in both the nucleus and the cytoplasm. During early mouse development, HEX is expressed in the primitive endoderm of blastocyst.

Number of pericryptal fibroblasts correlates with density of distinct mast cell phenotypes in the crypt lamina propria of human duodenum: implications for the homeostasis of villous architecture.

Pericryptal fibroblasts (PFs), a class of myofibroblasts, have strongly been implicated in the regulation of villous structure because of their location close to crypts and their ability to secrete cytokines affecting intestinal epithelial cell proliferation and differentiation. Recently, mast cells (MCs) have also been involved in the homeostasis of villous architecture. As myofibroblasts arise in a wide variety of settings concurrently with a local increase in the number of tissue MCs, we calculated in this study the density of both PF and distinct pericryptal MC phenotypes in the mucosa of human duodenum showing normal, defective, or atrophic villous profiles.

PTEN and Egr-1 expression in thyroid proliferative lesions.

PTEN is a tumor suppressor gene that inhibits cell cycle progression. Recent data support that PTEN transcription is upregulated by Egr-1. The present study evaluated the immunohistochemical expression of PTEN and Egr-1 in normal thyroid and in its benign and malignant proliferative lesions.

Nuclear localization of Galectin-3 in transformed thyroid cells: a role in transcriptional regulation.

The differential proteomic approach (2D gel analysis coupled to MALDI-MS analysis) of nuclear proteins can provide an extremely useful tool to understand control of cell proliferation and differentiation. In order to identify possible markers of dedifferentiation between normal and cancerous thyroid cells, we used a differential proteomics approach by comparing nuclear extracts from the normal rat thyroid cell line FRTL-5 and the completely undifferentiated Ki-mol cell line, obtained by transformation with the Ki-ras oncogene. Galectin-3 (Gal-3) was identified as highly expressed, in the nuclear compartment, only in the transformed cell line.