Different Thymosin Beta 4 Immunoreactivity in Foetal and Adult Gastrointestinal Tract

Background: Thymosin beta 4 (T beta(4)) is a member of beta-thymosins, a family of peptides that play essential roles in many cellular functions. A recent study from our group suggested a role for T beta(4) in the development of human salivary glands. The aim of this study was to analyze the expression of T beta(4) in the human gut during development, and in the adult. Methodology/Principal Findings: Immunolocalization of T beta(4) was studied in autoptic samples of tongue, oesophagus, stomach, ileum, colon, liver and pancreas obtained from two human foetuses and two adults. T beta(4) appeared unevenly distributed, with marked differences between foetuses and adults. In the stomach, superficial epithelium was positive in foetuses and negative in adults. Ileal enterocytes were strongly positive in the adult and weakly positive in the foetuses. An increase in reactivity for T beta(4) was observed in superficial colon epithelium of adults as compared with the foetuses. Striking differences were found between foetal and adult liver: the former showed a very low reactivity for T beta(4) while in the adult we observed a strong reactivity in the vast majority of the hepatocytes. A peculiar pattern was found in the pancreas, with the strongest reactivity observed in foetal and adult islet cells. Significance: Our data show a strong expression of T beta(4) in the human gut and in endocrine pancreas during development. The observed differential expression of T beta(4) suggests specific roles of the peptide in the gut of foetuses and adults. The observed heterogeneity of T beta(4) expression in the foetal life, ranging from a very rare detection in liver cells up to a diffuse reactivity in endocrine pancreas, should be taken into account when the role of T beta(4) in the development of human embryo is assessed. Future studies are needed to shed light on the link between T beta(4) and organogenesis

Oct-4 is highly expressed in stem/progenitor cells and in primordial follicles of the fetal human ovary

Oct-4 (Octamer-binding transcription factor 4) is a member of the POU (Pit-Oct-Unc) family. During development, Oct-4 is expressed in embryonic stem cells and in germ cell precursors. In this study, we investigated the expression of Oct-4 in the ovaries of human fetuses during gestation. The ovaries of 14 human fetuses and newborns, ranging in gestational age from 12 up to 38 weeks of gestation, were formalin-fixed, routinely processed and paraffin-embedded. Paraffin sections were immunostained with an anti-Oct-4 commercial antibody. Oct-4 expression was demonstrated in all the ovaries analyzed. Immunoreactivity for Oct-4 was detected in multiple stem/progenitor cells, including oogonia. Moreover, Oct-4 was expressed in oocytes, in primordial follicles. In ovarian stem/progenitor cells, Oct-4 was expressed in the nucleus, whereas in oocytes reactivity for Oct-4 was restricted to the cytoplasm. In the initial stages of gestation, the majority of Oct-4-positive precursor cells were detected in the external cortex. These preliminary data indicate Oct-4 as a major player in germ cell differentiation in the human ovary and as a useful marker for ovarian stem/progenitor cells. Given the ability of Oct-4 for the detection of ovarian stem/progenitor cells, further studies are needed in order to verify its ability to detect stem cells in adult ovaries

Thymosin β 4 in colorectal cancer is localized predominantly at the invasion front in tumor cells undergoing epithelial mesenchymal transition.

Thymosin β 4 (Tβ(4)) is a ubiquitous peptide that plays pivotal roles in the cytoskeletal system and in cell differentiation during embryogenesis. Recently, a role for Tβ(4) has been proposed in experimental and human carcinogenesis. This study was aimed at evaluating the correlation between Tβ(4) immunoractivity and colorectal cancer, with particular attemption to tumor cells undergoing epithelial-mesenchymal transition.86 intestinal biopsies were retrospectively analyzed including 76 colorectal adenocarcinomas with evident features of epithelial-mesenchymal transition, and 10 samples of normal colorectal mucosa. Paraffin sections were immunostained for Tβ(4) and for E-cadherin. Total RNA was isolated from frozen specimens obtained, at surgery, from the normal colon mucosa, the deeper regions and the superficial tumor regions in four cases of colon cancer. Tβ(4) immunoreactivity was detected in the vast majority (59/76) of colon carcinomas, showing a patchy distribution, with well differentiated areas significantly more reactive than the less differentiated tumor zones. We also noted a zonal pattern in the majority of tumors, characterized by a progressive increase in immunostaining for Tβ(4) from the superficial toward the deepest tumor regions. The strongest expression for Tβ(4) was frequently detected in invading tumor cells with features of epithelial-mesenchymal transition. The increase in reactivity for Tβ(4) matched with a progressive decrease in E-cadherin expression in invading cancer cells. At mRNA level, the differences in Tβ(4) expression between the surrounding colon mucosa and the tumors samples were not significant.Our data show that Tβ(4) is expressed in the majority of colon cancers, with preferential immunoreactivity in deep tumor regions. The preferential expression of the peptide and the increase in intensity of the immunostaining at the invasion front suggests a possible link between the peptide and the process of epithelial mesenchymal transition, suggesting a role for Tβ(4) in colorectal cancer invasion and metastasis

New Horizons in Metastatic Colorectal Cancer: Prognostic Role of CD44 Expression

Background: The transmembrane glycoprotein CD44, the major hyaluronan (HA) receptor, has been proven to regulate cell growth, survival, differentiation, and migration. It is therefore widely considered to be involved in carcinogenesis. Its role as a new therapeutic target in solid tumors is under evaluation in clinical trials. The prognostic value remains controversial. Here, we aimed to investigate the correlation between CD44 expression and the clinicopathological features and survival in metastatic colorectal cancer (mCRC) patients. Methods: Data from 65 mCRC patients of the Medical Oncology Unit, University Hospital and University of Cagliari were retrospectively collected from 2008 to 2021. Immunohistochemical analysis was performed at the Pathology Division, University Hospital of Cagliari on 3 μm thick sections obtained from paraffin blocks. The intensity of immunohistochemical staining was subclassified into four groups: score 0 if negative or weak membrane staining in less than 10% of tumor cells; score 1+ if weak membrane staining in at least 10% of tumor cells or moderate membrane staining in less than 10% of tumor cells; score 2+ if moderate membrane staining in at least 10% of tumor cells or intensive membrane staining in less than 10% of tumor cells; score 3+ if intense membrane staining in at least 10% of tumor cells. Based on this score, we distinguished patients into low CD44 expression (score 0, 1+, 2+) and high CD44 expression (score 3+). Statistical analysis was performed with MedCalc (survival distribution: Kaplan-Meier; survival comparison: log-rank test; association between categorical variables: Fisher's exact test). Results: Patients' median age was 66 years (range 49-85). Regarding CD44 expression, score was 0 in 18 patients, 1+ in 15 patients, 2+ in 18 patients, and 3+ in 14 patients. Median overall survival (mOS) was 28.1 months (95%CI: 21.3-101). CD44 overexpression (3+) was correlated with poor prognosis (p = 0.0011; HR = 0.2), with a mOS of 14.5 months (95%CI 11.7 to 35.9) versus 30.7 months (95%CI 27.8 to 101) in lower CD44 expression. Higher CD44 expression was associated with clinically poor prognostic features: age ≥ 70 years (p = 0.0166); inoperable disease (p = 0.0008); stage IV at diagnosis (p = 0.0241); BRAF mutated (p = 0.0111), high-grade tumor (p = 0.0084). Conclusions: CD44 markedly correlated with aggressive tumor behavior and contributed to the earlier progression of disease, thus suggesting its role as a novel prognostic marker and potential therapeutic target for mCRC patients

ISL-1: a new potential marker of stem/progenitor cells in the developing human uterus

The human uterus is a highly dynamic organ with peculiar plasticity and marked reproductive ability, due to the presence of a vast number of multiple stem/progenitor cell types, including endometrial, stromal and vascular progenitor cells. Conflicting results have been published regarding which uterine population might represent the real stem/progenitor cell fraction in terms of in vivo stem cell activity. Human endometrial side population (ESP) cells were shown to differentiate into multiple endometrial lineages in the stem cell niche provided by whole endometrial cells, suggesting that ESP cells might represent the most important stem/progenitor cells responsible of the cyclical regeneration of the endometrium throughout a woman’s reproductive life. This study was aimed at analyzing the localization, composition, and occurrence of stem cell niches in the human fetal uterus at different stages of development. To this end, the whole uterus was obtained at autopsy by 12 human fetuses and newborns, ranging in gestational age from 12 up to 39 weeks of gestation. Tissue paraffin sections were immunostained with antibodies against insulin gene enhancer protein (ISL-1), a transcription factor previously utilized as a marker of stem/progenitor cells in the pancreas, heart and nervous system. Reactivity for ISL-1 was detected in both epithelial and stromal uterine precursors, at all gestational ages, allowing the detection of uterine progenitor cells. The loss of reactivity for ISL-1 in some stromal cell precursors was interpreted as a sign of differentiation. These preliminary data indicate ISL-1 as a useful marker for the detection of stem/progenitor cells in the human fetal endometrium. Further studies are needed to verify the utility of ISL-1 as a marker of stem/progenitor cells in the adult endometrium

Gold Nanoparticles: A New Golden Era in Oncology?

In recent years, the spectrum of possible applications of gold in diagnostics and therapeutic approaches in clinical practice has changed significantly, becoming surprisingly broad. Nowadays, gold-based therapeutic agents are used in the therapy of multiple human diseases, ranging from degenerative to infectious diseases and, in particular, to cancer. At the basis of these performances of gold, there is the development of new gold-based nanoparticles, characterized by a promising risk/benefit ratio that favors their introduction in clinical trials. Gold nanoparticles appear as attractive elements in nanomedicine, a branch of modern clinical medicine, which combines high selectivity in targeting tumor cells and low toxicity. Thanks to these peculiar characteristics, gold nanoparticles appear as the starting point for the development of new gold-based therapeutic strategies in oncology. Here, the new gold-based therapeutic agents developed in recent years are described, with particular emphasis on the possible applications in clinical practice as anticancer agents, with the aim that their application will give rise to a new golden age in oncology and a breakthrough in the fight against cancer.status: publishe

Immunohistochemical detection of thymosin β4 in foetal and adult pancreas.

<p><b>a</b>) Foetal pancreas: immunoreactivity for Tβ₄ is localized inside the islets of Langherans. Some of endocrine cells show the entire cytoplasm strongly immunoreactive for the peptide (arrows). Few Tβ₄-reactive cells are also present in the exocrine pancreas, inside the tubular structures (arrowhead). (Original Magnification ×400). <b>b</b>) Adult pancreas: the highest reactivity for Tβ₄ is observed in Langherans islet cells, which show diffuse fine granular deposits in their cytoplasm (arrows). (Original Magnification ×400).</p

Immunohistochemical detection of thymosin β4 in foetal and adult ileum.

<p><b>a</b>) Foetal ileum: a granular reactivity for Tβ₄ is present in the epithelium covering ileal villi (arrow). A reactivity for the peptide is also observed in the mucous occupying the intestinal lumen (arrowhead). (Original Magnification ×400) <b>b</b>) Adult ileum: a mild reactivity for Tβ₄ is present in the cytoplasm of enterocytes covering villi (arrows). (Original Magnification ×250)</p