Characterization of tumor-derived mesenchymal stem cells potentially differentiating into cancer-associated fibroblasts in lung cancer.

PURPOSE: The goal of this study was to understand if mesenchymal stem cells isolated from lung tumor tissue (T-MSCs) may differentiate into cancer associated fibroblasts (CAFs), that promote neoplastic progression, angiogenesis and metastasis in the epithelial solid tumors, mimicking the tumor microenvironmental influence. METHODS: MSCs were been obtained from healthy (Control, C-MSCs) and tumor (T-MSCs) tissue of one patient who underwent a lobectomy for a lung adenocarcinoma pT1bN0. Isolated cells were characterized for the presence of molecular markers (identified by routine diagnostic characterization in differentiated tumoral cells), stemness properties, and CAF-related markers expression. Subsequently, cells were co-cultured with a lung adenocarcinoma cell line (A549 cells) to evaluate the effects on proliferation, oncogene expression and IL6 secretion. RESULTS: C- and T-MSCs did not present EGFR mutations unlike tumor tissue and showed a stem-like immunophenotype, characterized by the ability to differentiate towards osteo-, chondro- and adipogenic lineages. The expression of markers referred to CAFs (α-SMA, HI-1α, MMP11, VEGF, CXCL12, TGF-ß1, TGF-ßRII, IL6, TNFα) was significantly higher in T-MSCs than in C-MSCs. The co-cultures with A549 cells led to the over-expression of selected oncogenes and to the increase of IL6 secretion in T-MSCs but not in C-MSCs. CONCLUSIONS: MSCs isolated from tumor tissue displayed distinct properties compared to MSCs isolated from healthy tissue, suggesting T-MSCs differentiation towards a CAF-related phenotype under the influence of the tumoral microenvironment.

Indirect co-cultures of healthy mesenchymal stem cells restore the physiological phenotypical profile of psoriatic mesenchymal stem cells.

Psoriasis microenvironment, characterized by an imbalance between T helper type 1 (Th1)/Th17 and Th2 cytokines and also influences the mesenchymal stem cells (MSCs) phenotypical profile. MSCs from healthy donors (H-MSCs) can exert a strong paracrine effect by secreting active soluble factors, able to modulate the inflammation in the microenvironment. To evaluate the influence of H-MSCs on MSCs from psoriatic patients (PsO-MSCs), H-MSCs and PsO-MSCs were isolated and characterized. Indirect co-culture of H-MSCs with PsO-MSCs was performed; effects on proliferation and expression of cytokines linked to Th1/Th17 and Th2 pathways were assayed before and after co-culture. The results show that before co-culture, proliferation of PsO-MSCs was significantly higher than H-MSCs (P < 0·05) and the levels of secreted cytokines confirmed the imbalance of Th1/Th17 versus the Th2 axis. After co-culture of H-MSCs with PsO-MSCs, healthy MSCs seem to exert a 'positive' influence on PsO-MSCs, driving the inflammatory phenotypical profile of PsO-MSCs towards a physiological pattern. The proliferation rate decreased towards values nearer to those observed in H-MSCs and the secretion of the cytokines that mostly identified the inflammatory microenvironment that characterized psoriasis, such as interleukin (IL)-6, IL-12, IL-13, IL-17A, tumour necrosis factor (TNF)-α and granulocyte-macrophage colony-stimulating factor (G-CSF), is significantly lower in co-cultured PsO-MSCs than in individually cultured PSO-MSCs (P at least < 0·05). In conclusion, our preliminary results seem to provide an intriguing molecular explanation for the ever-increasing evidence of therapeutic efficacy of allogeneic MSCs infusion in psoriatic patients.

Pituitary adenomas, stem cells, and cancer stem cells: what's new?

PURPOSE: To clarify the existence of pituitary stem cells (SCs) both in the embryonic and the postnatal gland and the role for SCs in pituitary adenomas. METHODS: This work, which does not address the pathogenesis of pituitary adenomas, reviews the latest research findings and discoveries on SCs in pituitary and cancer SCs (CSCs) in pituitary adenomas and discusses the involvement of the EMT. RESULTS: Several groups using different approaches and techniques have demonstrated the existence of SCs and CSCs and as they are major players in pituitary adenoma onset. CONCLUSIONS: As in other benign and malignant tumors, the hypothesis that CSCs play a pivotal role in pituitary adenoma onset has been confirmed as well as the existence of a link between the epithelial-to-mesenchymal transition (EMT) process and CSC formation in epithelial tumors.

T helper (Th)1, Th17 and Th2 imbalance in mesenchymal stem cells of adult patients with atopic dermatitis: at the origin of the problem.

BACKGROUND: Atopic dermatitis (AD) is a chronic and inflammatory disease characterized by a marked imbalance of T helper (Th)2 vs. Th1/Th17 cells in the early phase of AD, whereas a mixed Th1/Th2 pattern of inflammation is usually found at the chronic stage. These features have not been extensively evaluated in undifferentiated skin cells of patients affected by AD. OBJECTIVES: To evaluate the relative expression of 22 genes encoding Th1, Th2 and Th17 cytokines and the secretion of the corresponding proteins in cutaneous mesenchymal stem cells (MSCs) isolated from skin of patients with AD (AD-MSCs) and their role in AD onset. METHODS: AD-MSCs were isolated, characterized and profiled by polymerase chain reaction array and enzyme-linked immunosorbent assay for the relative expression and secretion of cytokines involved in the Th1, Th2 and Th17 pathways. MSCs isolated from the skin of healthy people were used as controls (C-MSCs). RESULTS: AD-MSCs showed an upregulation of many Th1/Th17 cytokines [interleukin (IL)-6, IL-8, IL-12, IL-13, IL-17A, IL-17F, transforming growth factor-ß, interferon-γ], while Th2 chemokines (IL-2, IL-4, IL-5, IL-23A) were downregulated in AD-MSCs. Finally, some genes/proteins (CCL1, IL-17C, tumour necrosis factor-α) did not show variations between C-MSCs and AD-MSCs. CONCLUSIONS: The profile of MSCs obtained from patients with chronic AD retraces the Th1/Th17 cell environment observed in differentiated cells of chronic AD. This evidence could open a new scenario in the pathogenesis of AD, according to which the inflammatory process may involve MSCs early on.

MSCs and inflammation: new insights into the potential association between ALCL and breast implants.

Possible association between anaplastic large cell lymphoma (ALCL) and breast implants has been suggested. In this context, formation of the periprosthetic capsule has been reported as a cause of inflammation, which plays a key role in tumor onset. Tumors take advantage of inflammation to influence and interfere with the host immune response by secreting multiple factors, and their onset and survival is in turn affected by the paracrine effects from mesenchymal stem cells (MSCs). In this study, we tried to clarify how inflammation can modify the immunobiology and the exerted paracrine effect of MSCs. MSCs derived from both inflamed (I-MSCs) and control (C-MSCs) tissues were isolated and co-cultured with an ALCL cell line. Proliferation rate and the expression of selected cytokines were tested. I-MSCs secrete higher levels of cytokine related to chronic inflammation than C-MSCs. After co-cultures with KI-JK cells, C- and I-MSCs show the same variation in the cytokine expression, with an increase of IL2, IL4, IL5, IL10, IL13, TNF-α, TGF-ß, and G-CSF. Proliferation of ALCL cells was not influenced by co-cultures. Our results state that (i) inflamed microenvironment affects the immunobiology of MSCs modifying the profile of the expressed cytokines, and (ii) the paracrine effects exerted by MSCs on ALCL cells are not influenced by inflammation. Moreover, it seems that ALCL cells are able to manipulate MSCs' immunoregulatory properties to evade the host immune control. Nevertheless, this ability is not associated with inflammation and the question about BIA-ALCL is not proved by our experiments.

New miRNAs network in human mesenchymal stem cells derived from skin and amniotic fluid.

Mesenchymal stem cells (MSCs), isolated from different adult sources, have great appeal for therapeutic applications due to their simple isolation, extensive expansion potential, and high differentiative potential.In our previous studies we isolated MSCs form amniotic fluid (AF-MSCs) and skin (S-MSCs) and characterized them according to their phenotype, pluripotency, and mRNA/microRNAs (miRNAs) profiling using Card A from Life Technologies.Here, we enlarge the profiling of AF-MCSs and S-MSCs to the more recently discovered miRNAs (Card B by Life Technologies) to identify the miRNAs putative target genes and the relative signaling pathways. Card B, in fact, contains miRNAs whose role and target are not yet elucidated.The expression of the analyzed miRNAs is changing between S-MSCs and AF-MSCs, indicating that these two types of MSCs show differences potentially related to their source. Interestingly, the pathways targeted by the miRNAS deriving from Card B are the same found during the analysis of miRNAs from Card A.This result confirms the key role played by WNT and TGF-ß pathways in stem cell fate, underlining as other miRNAs partially ignored up to now deserve to be reconsidered. In addition, this analysis allows including Adherens junction pathways among the mechanisms finely regulated in stem cell behavior.

Bortezomib-induced peripheral neurotoxicity in human multiple myeloma-bearing mice.

The proteasome inhibitor bortezomib is an antineoplastic drug mainly used for the treatment of multiple myeloma (MM). Despite its effectiveness, bortezomib clinical use is often limited by the onset of peripheral neuropathy (BiPN). To better understand the mechanisms of BiPN several rat and mice models have been proposed, but no studies in MM-bearing animals allowing to test the antitumor activity of the selected schedules and the role of MM by itself in peripheral nervous system damage have been reported to date. Here, we carried out a study using immunodeficient C.B-17/Prkdcscid (SCID) mice injected with RPMI8266 human MM cells and treated with bortezomib 1 mg/kg once a week for five weeks. Animals were assessed with neurophysiological, behavioral and pathological methods and tumor volume measurement was performed along the study. At the end of the study BiPN was evident in bortezomib-treated animals, and this neurotoxic effect was evident using a schedule able to effectively prevent tumor growth. However, neurophysiological and pathological evidence of MM induced peripheral nervous system damage was also reported. This model based on MM-bearing animals is more reliable in the reproduction of the clinical setting and it is, therefore, more suitable than the previously reported models of BiPN to study its pathogenesis. Moreover, it represents an optimal model to test the efficacy of neuroprotective agents and at the same time their non-interference with bortezomib antineoplastic activity.

Isolation and characterization of progenitor mesenchymal cells in human pituitary tumors.

The Cancer Stem Cells (CSCs) theory suggests that genetic alterations in stem cells are the direct cause for cancer. The evidence for a CSC population that results in pituitary tumors is poor. Some studies report the isolation of CSCs, but a deep characterization of the stemness of these cells is lacking. Here, we report the isolation and detailed characterization of progenitor mesenchymal cells (PMCs) from both growth hormone-secreting (GH(+)) and non-secreting (NS) pituitary adenomas, determining the immunophenotype, the expression of genes related to stemness or to pituitary hormone cell types, and the differentiative potential towards osteo-, chondro- and adipogenic lineages. Finally, the expression of CD133, known as a marker for CSCs in other tumors, was analyzed. Isolated cells, both from GH(+) and NS tumors, satisfy all the criteria for the identification of PMCs and express known stem cell markers (OCT4, SOX2, KLF4, NANOG), but do not express markers of pituitary hormone cell types (PITX2, PROP1, PIT1). Finally, PMCs express CD133. We demonstrated that pituitary tumors contain a stem cell population that can generate cell types characteristic of mesenchymal stem cells, and express CD133, which is associated with CSCs in other tumors.

Characterization and profiling of immunomodulatory genes in resident mesenchymal stem cells reflect the Th1-Th17/Th2 imbalance of psoriasis.

The expression of genes encoding for Th1, Th2 and Th17 cytokines has been extensively evaluated in differentiated skin cells of psoriatic patients. The microenvironment exerts a control on the phenotype of resident mesenchymal stem cells (MSCs) into the skin of psoriasis patients. Aim of the study was to extensively evaluate the relative expression of 43 genes encoding for Th1, Th2 and Th17 cytokines in MSCs isolated from skin of psoriasis patients. MSCs resident into psoriatic skin were isolated, characterized and profiled by PCR array for the relative expression of genes encoding for cytokines involved in Th1, Th2 and Th17 pathways. MSCs isolated from the skin of healthy subjects were used as control. The MSCs isolated from skin of psoriasis patients showed a greater relative expression of the most part of the analyzed genes encoding for Th1 and Th17 cytokines: INF-γ, CCR5, CXCL9, CXCL10, IL6, IL8, TNF-α, IL23A, CCL2, CCL20, CXCL2, CXCL5, IL17C, IL17F, IL17RA, IL21, TLR2 than healthy subjects. On the contrary, the relative expression of genes encoding for Th2 cytokines: CCL1, CCL22, CXCL12, IL2, IL3, IL4, IL13B, IL 22, IL 27, TGF-ß1, was similar between the MSCs isolated from psoriasis and healthy subjects. In conclusion, the MSCs isolated from psoriasis show an imbalance between the Th1-Th17 and Th2 pathways, which reflects the well-known abnormal balance observed in differentiated skin cells. This evidence could strengthen the hypothesis of an early involvement of resident MSCs in the pathogenesis of psoriasis.

Skin-derived mesenchymal stem cells: isolation, culture, and characterization.

The increasing interest about stem cell research is linked to the promise of developing such treatments for many life-threatening, debilitating diseases and for cell replacement therapies. Among the various human tissues, skin represents a source characterized by great accessibility and availability with noninvasive procedures and without risks of oncogenesis after their transplantation. In this aim, the identification of suitable protocols for the isolation, characterization, and long-term storage has a pivotal role.

Alterations of ROS pathways in scleroderma begin at stem cell level.

Scleroderma is a chronic systemic autoimmune disease (primarily of the skin) characterized by fibrosis (or hardening), vascular alterations and autoantibodies production.There are currently no effective therapies against this devastating and often lethal disorder. Despite the interest for the immunomodulatory effects of mesenchymal stem cells (MSCs) in autoimmune diseases, the role of MSCs in scleroderma is still unknown. A pivotal role in scleroderma onset is played by oxidative stress associated with the accumulation of great amounts of reactive oxygen species (ROS). This study depicts some phenotypic and functional features of MSCs isolated from the skin of healthy and scleroderma patients; the ROS production and accumulation, the expression of ERK1/2 and the effects of the stimulation with PDGF, were analyzed in MSCs; results were compared to those observed in primary fibroblasts (Fbs) isolated from the same subjects. We found that the pro-oxidant environment exerted by scleroderma affects MSCs, which are still able to counteract the ROS accumulation by improving the antioxidant defenses. On the contrary, scleroderma fibroblasts show a disruption of these mechanisms, with consequent ROS increase and the activation of the cascade triggered by scleroderma auto-antibodies against PDGFR.

In vitro evaluation of mesenchymal stem cell isolation possibility from different intra-oral tissues.

Mesenchymal stem cells (MSCs) are of great interest for the regeneration of tissues and organs. Bone marrow is the first sources of MSCs, but in the recent years there has been interest in other tissues for the isolation of these pluripotent cells. In this study, we investigated the features of MSCs isolated from different oral regions in order to evaluate their potential application in the regeneration of damaged maxillofacial tissues. Sampling from human periodontal ligament, dental pulp, maxillary periosteum as well as bone marrow were collected in order to obtain different stem cell populations. Cells were morphologically and immunophenotipically characterized. Their proliferation potential and their ability to differentiate in osteoblasts were also assessed. All tested cell population showed a similar fibroblast-like morphology and superimposable immunophenotype. Slight differences were observed in proliferation and differentiation potential. Cells isolated from human periodontal ligament, dental pulp, maxillary periosteum had the characteristics of stem cells. Considering their peculiar feature they may alternatively represent interesting cell sources in stem cell-based bone/periodontal tissue regeneration approaches.

Effect of biologic therapies targeting tumour necrosis factor-α on cutaneous mesenchymal stem cells in psoriasis.

BACKGROUND: Psoriasis is a Th1 immune-mediated, inflammatory disease, in which skin lesions appear many years before the related metabolic and cardiovascular comorbidities, according to the theory of the 'psoriatic march'. Inducible nitric oxide synthetase (iNOS), tumour necrosis factor (TNF)-α and vascular endothelial growth factor (VEGF) are directly implicated in determining both skin lesions and systemic involvement in psoriasis. Reactive oxygen species actively promote the secretion of inflammatory Th1 cytokines directly involved in the pathogenesis of psoriasis. OBJECTIVES: Evaluation of VEGF expression and production, nitric oxide (NO) production, iNOS expression, and the antioxidant response of mesenchymal stem cells (MSCs), both before and after 12 weeks of treatment with the TNF-α inhibitors adalimumab or etanercept. METHODS: Biochemical, morphological and immunohistochemical analyses were performed in MSCs isolated from nonlesional, perilesional and lesional skin of patients with psoriasis, before and after treatment. RESULTS: The treatments were able to reduce the expression and production of VEGF, the expression of iNOS and the production of NO in MSCs of patients with psoriasis. TNF-α inhibitors also reduced the oxidative damage in MSC membrane and proteins, several antioxidant systems responded to treatments with a general inhibition of activities (glutathione S-transferase and catalase) and these effects were also supported by a general decrease of total oxyradical scavenging capacity towards hydroxyl radicals and peroxynitrite. CONCLUSIONS: TNF-α inhibitors are able to change the physiopathological pathway of psoriasis, and our results suggest their therapeutic effects already take place at the level of MSCs, which probably represent the cells primarily involved in the 'psoriatic march'.

The mesenchymal stem cell profile in psoriasis.

BACKGROUND: The expression of inducible nitric oxide synthase (iNOS) and vascular endothelial growth factor (VEGF) and the level of total oxyradical scavenging capacity have been evaluated extensively in the cutaneous cells of patients with psoriasis. As yet, no indications are available about the undifferentiated cells, the mesenchymal stem cells (MSCs), isolated from skin. OBJECTIVES: To isolate MSCs in patients with psoriasis and to compare them with those obtained from atopic and healthy subjects, in order to analyse whether MSCs show some typical psoriatic profiles and to understand whether pathophysiological events leading to psoriasis start early at the stem cell level. METHODS: MSCs isolated from seven patients with psoriasis, seven patients with acute atopic dermatitis and seven healthy subjects were characterized by fluorescence-activated cell sorting analysis. VEGF and nitric oxide (NO) content was measured in conditioned medium, the expression of VEGF and iNOS was analysed by immunohistochemistry, and the total oxyradical scavenging capacity towards peroxynitrite was tested. RESULTS: VEGF content was highest in the medium conditioned by psoriatic perilesional MSCs, whereas NO concentration was maximally increased in medium conditioned by MSCs isolated from lesional psoriatic skin. The ability to neutralize the oxidizing effects of peroxynitrite was lower for MSCs isolated from lesional psoriatic skin compared with other MSCs, except for MSCs of lesional atopic skin. CONCLUSIONS: The microenvironment in psoriasis differs from those of atopic dermatitis and healthy skin; it could induce resident MSCs to produce angiogenic and proinflammatory mediators which lead to a reduction in the antioxidant capacity of these cells, contributing to the development of skin lesions in psoriasis.

Neurogenic potential of mesenchymal-like stem cells from human amniotic fluid: the influence of extracellular growth factors.

Amniotic fluids contain human stem cells, among which mesenchymal stem cells could be isolated. These cells have multipotent differentiation ability and no tumorigenic potential after transplantation in mice. These features make them good candidates for in vitro studies and for therapeutic purposes. The aim of this study was to isolate mesenchymal stem cell-like cultures from different amniotic fluids in order to study in vitro their neurogenic potential and assess if this process could be reproducible and standardized. We focused attention on the possible differential effects of soluble growth factors. Immunophenotypical and molecular characterization showed that the 31 amniotic fluid-derived cultures expressed mesenchymal markers as well as some stemness properties. These cells also appeared to be responsive to purines or acetylcholine showing an intracellular calcium increase, also reported for mesenchymal stem cells derived from other sources. Interestingly, in the presence of retinoic acid, these cells assumed a neuronal-like morphology. In addition, functional and molecular analyses revealed that retinoic acid-treated cells showed immature electric functional properties, the expression of neuronal markers and stemness genes. In conclusion, even if further investigations are required, the results presented here contribute to support the finding that amniotic fluid contains cells able to differentiate in vitro towards neural-like lineage in the presence of retinoic acid. The ability of retinoic acid to induce a possible neuronal progenitor culture makes the model useful to study a possible in vivo transplantation of these cells and to contribute to define the protocols for cell therapy.

Ciprofloxacin-modified electrosynthesized hydrogel coatings to prevent titanium-implant-associated infections.

New promising and versatile materials for the development of in situ sustained release systems consisting of thin films of either poly(2-hydroxyethyl methacrylate) or a copolymer based on poly(ethylene-glycol diacrylate) and acrylic acid were investigated. These polymers were electrosynthesized directly on titanium substrates and loaded with ciprofloxacin (CIP) either during or after the synthesis step. X-ray photoelectron spectroscopy was used to check the CIP entrapment efficiency as well as its surface availability in the hydrogel films, while high-performance liquid chromatography was employed to assess the release property of the films and to quantify the amount of CIP released by the coatings. These systems were then tested to evaluate the in vitro inhibition of methicillin-resistant Staphylococcus aureus (MRSA) growth. Moreover, a model equation is proposed which can easily correlate the diameter of the inhibition haloes with the amount of antibiotic released. Finally, MG63 human osteoblast-like cells were employed to assess the biocompatibility of CIP-modified hydrogel coatings.

Functional assay, expression of growth factors and proteins modulating bone-arrangement in human osteoblasts seeded on an anorganic bovine bone biomaterial.

The basic aspects of bone tissue engineering include chemical composition and geometry of the scaffold design, because it is very important to improve not only cell attachment and growth but especially osteodifferentiation, bone tissue formation, and vascularization. Geistlich Bio-Oss (GBO) is a xenograft consisting of deproteinized, sterilized bovine bone, chemically and physically identical to the mineral phase of human bone. In this study, we investigated the growth behaviour and the ability to form focal adhesions on the substrate, using vinculin, a cytoskeletal protein, as a marker. Moreover, the expression of bone specific proteins and growth factors such as type I collagen, osteopontin, bone sialoprotein, bone morphogenetic protein-2 (BMP-2), BMP-7 and de novo synthesis of osteocalcin in normal human osteoblasts (NHOst) seeded on xenogenic GBO were evaluated. Our observations suggest that after four weeks of culture in differentiation medium, the NHOst showed a high affinity for the three dimensional biomaterial; in fact, cellular proliferation, migration and colonization were clearly evident. The osteogenic differentiation process, as demonstrated by morphological, histochemical, energy dispersive X-ray microanalysis and biochemical analysis was mostly obvious in the NHOst grown on three-dimensional inorganic bovine bone biomaterial. Functional studies displayed a clear and significant response to calcitonin when the cells were differentiated. In addition, the presence of the biomaterial improved the response, suggesting that it could drive the differentiation of these cells towards a more differentiated osteogenic phenotype. These results encourage us to consider GBO an adequate biocompatible three-dimensional biomaterial, indicating its potential use for the development of tissue-engineering techniques.

Oxidative stress defense in human-skin-derived mesenchymal stem cells versus human keratinocytes: Different mechanisms of protection and cell selection.

Stem cells are undifferentiated cells with the capacity for self-renewal and differentiation. Here we have determined the susceptibility to oxidative stress of isolated mesenchymal stem cells from human skin (S-MSCs) in comparison with keratinocytes, which are differentiated cells of the same lineage. To induce pro-oxidant conditions, S-MSCs and keratinocytes were exposed to 0.5mM H(2)O(2) for 2 h, with oxidative effects analyzed after 4, 12, 24, and 48 h of recovery, in terms of cell growth, vitality, apoptosis, DNA damage, variations in individual antioxidant defense and total oxyradical scavenging capacity toward peroxyl and hydroxyl radicals. The data indicate different abilities across these two cell types to counteract this oxidative stress, which reflects stress that would normally be experienced by these cells under basal conditions. Human keratinocytes seem to have much greater antioxidant defense to counteract the oxidative injury to which they are continuously exposed in the skin. The S-MSCs are surrounded by a complex microenvironment that protects them from external insults, and so they do not have a particularly efficient defense system, and they were generally less responsive to enhanced pro-oxidant challenge. S-MSCs seem particularly prone to apoptotic events, which might thus represent their primary defense mechanism against stress.