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In the last decades, the therapeutic potential of hematopoietic stem cell transplantation (HSCT) has acquired a primary role in the management of a broad spectrum of diseases including cancer, hematologic conditions, immune system dysregulations, and inborn errors of metabolism. The different types of HSCT, autologous and allogeneic, include risks of severe complications including acute and chronic graft-versus-host disease (GvHD) complications, hepatic veno-occlusive disease, lung injury, and infections. Despite being a dangerous procedure, it improved patient survival. Hence, its use was extended to treat autoimmune diseases, metabolic disorders, malignant infantile disorders, and hereditary skeletal dysplasia. HSCT is performed to restore or treat various congenital conditions in which immunologic functions are compromised, for instance, by chemo- and radiotherapy, and involves the administration of hematopoietic stem cells (HSCs) in patients with depleted or dysfunctional bone marrow (BM). Since HSCs biology is tightly regulated by oxidative stress (OS), the control of reactive oxygen species (ROS) levels is important to maintain their self-renewal capacity. In quiescent HSCs, low ROS levels are essential for stemness maintenance; however, physiological ROS levels promote HSC proliferation and differentiation. High ROS levels are mainly involved in short-term repopulation, whereas low ROS levels are associated with long-term repopulating ability. In this review, we aim summarize the current state of knowledge about the role of β3-adrenoreceptors (β3-ARs) in regulating HSCs redox homeostasis. β3-ARs play a major role in regulating stromal cell differentiation, and the antagonist SR59230A promotes differentiation of different progenitor cells in hematopoietic tumors, suggesting that β3-ARs agonism and antagonism could be exploited for clinical benefit.

We studied the effects of everolimus on the erythroid differentiation of human leukaemic K562 cells and on the cultures of erythroid progenitors derived from the peripheral blood of beta-thalassaemia patients. A quantitative real-time reverse-transcription polymerase chain reaction assay was employed for the quantification of the accumulation of globin mRNAs. The results obtained demonstrate that everolimus is a potent inducer of the erythroid differentiation of K562 cells. Erythroid induction is associated with an increase in alpha- and gamma-globin mRNAs. In erythroid precursor cells from 4 beta-thalassaemia patients, everolimus stimulated a preferential increase (ranging from 1.8- to 7.2-fold) in gamma-globin mRNA. Only minor effects were observed on the expression of alpha-globin genes. These results, in our opinion, are of interest as this compound is already employed in clinical trials as an anti-rejection agent following kidney transplantation. These data suggest that everolimus warrants further evaluation as a potential therapeutic drug in the treatment of beta-thalassaemia., (2007 S. Karger AG, Basel)

β3-adrenergic receptor (β3-AR) is the last β-adrenoceptor subtype identified. β3-AR is widely expressed and regulates numerous physiological processes, and it is also a potential target for the treatment of many diseases, including cancers. For some types of cancers, bone marrow transplant (BMT) represents a valid therapeutic support, especially in the case of the necessity of high-dose chemotherapy and radiotherapy. For a successful BMT, it is necessary that a donor's hematopoietic stem cells (HSCs) correctly reach the staminal niche in the recipient's bone marrow (BM) and contribute to restore normal hematopoiesis in order to rapidly repopulate BM and provide all the healthy blood cells of which the patient needs. Generally, it takes a long time. Control and accelerate homing and engraftment of HSCs could represent a helpful approach to avoid the complications and undesirable effects of BMT. The evidence that the β-adrenergic system has a role in the BM can be found in different studies, and this leads us to hypothesize that studying this field could be interesting to meliorate the most critical aspects of a BMT. Here, we collected the data present in literature about the role of β3-AR in the BM with the purpose of discovering a possible utility of β3-AR modulation in regulating HSC trafficking and hematopoiesis. [ABSTRACT FROM AUTHOR]

Although there is an increasing evidence that cancer stem cell (CSC) niches in the tumor microenvironment (TME) plays a crucial role in sustaining solid tumors progression, several molecular players involved in this regulation still remain unknown. The role of β-adrenergic signaling in enhancing tumor growth through β2-adrenoreceptors (β2-ARs) has been confirmed in different cancer models, but the role played by the β3-adrenergic receptor (β3-AR) has recently emerged. Previous studies showed that β3-AR promotes cancer growth through the activation of different stromal cells in the TME, and leads to melanoma malignancy progression through inflammation, angiogenesis, and immunotolerance. Here we show that in B16 melanoma-bearing mice, the pharmacological β3-AR blockade is able to reduce the expression of CSC markers, and to induce a differentiated phenotype of hematopoietic subpopulations in TME. In particular, cytofluorimetric analysis (FACS) of the tumor mass shows that β3-AR antagonist SR59230A promotes hematopoietic differentiation as indicated by increased ratios of lymphoid/hematopoietic stem cells (HSCs) and of myeloid progenitor cells/HSCs, and increases the number of Ter119 and natural killer (NK) precursor cells, and of granulocyte precursors, indicating active hematopoiesis within the tumor tissue. Moreover, pharmacological antagonism of β3-AR induces mesenchymal stem cell (MSC) differentiation into adipocytes subtracting a potential renewal of the stem compartment by these cells. Here we demonstrate that β3-AR blockade in the TME by inducing the differentiation of different stromal cells at the expense of stemness traits could possibly have a favorable effect on the control of melanoma progression. [ABSTRACT FROM AUTHOR]

Philadelphia-positive acute lymphoblastic leukemia (Ph+ ALL) still represents a major challenge. We report the experience of the Italian Association of Pediatric Hematology and Oncology (AIEOP) with allogeneic hematopoietic stem cell transplantation (HSCT) in children with Ph+ ALL from 1990 to 2008. Sixty-nine patients received HSCT from either a related (37, 54%) or an unrelated (32, 46%) donor. Twenty-five patients (36%) underwent transplantation before 2000 and 44 (64%) after 2000. Twenty-three patients (33%) received Imatinib mesylate treatment before HSCT and seven (10%) after HSCT. After a median follow-up of 56 months, the overall survival (OS) probability was 51% (95% confidence interval [CI], 38-63), the leukemia-free survival (LFS) was 47% (95% CI, 34-59), transplantation-related mortality (TRM) was 17% (95% CI, 10-30), and relapse incidence (RI) was 36% (95% CI, 26-50). Transplantation in first complete remission, female gender, and lower WBC count at diagnosis were associated with a better LFS in both univariate and multivariate analyses. Patients with p210 transcript had a trend for a worse prognosis compared with those who had the p190 transcript. Our series confirms the role of HSCT in the eradication of Ph+ ALL. Early HSCT is recommended once morphologic remission is obtained. [ABSTRACT FROM AUTHOR]