Review of clinical and haematological response to low-dose cytosine arabinoside in acute myeloid leukaemia

15 patients with acute myeloid leukaemia (AML) were treated with low-dose cytosine arabinoside (LD ARA-C). 2 patients had complete remissions, which lasted for 8 and 3 months, and 5 patients had a partial remission. 46% of the patients thus responded to LD ARA-C. This included 1 responding patient who had not previously responded to therapy with 6-mercaptopurine, thioguanine, or vinblastine. The 2 patients with complete remission did not show LD ARA-C-induced hypoplasia of bone marrow, although 1 had hypoplastic AML before therapy. Leukaemic cells from 1 patient showed in vivo maturation from M1 to M3 after LD ARA-C treatment. The present results, together with the published data, indicate that: a. LD ARA-C treatment, although it may have some toxic effects, is an effective treatment for some patients with AML, especially those with hypoplastic AML; b. Response to LD ARA-C can be obtained after one or several courses of treatment; c. LD ARA-C-induced remissions are sometimes obtained even in patients who fail in more conventional treatments; d. LD ARA-C-induced remissions can be achieved without bone marrow hypoplasia, and induction of hypoplasia by itself does not always result in complete remission; e. LD ARA-C can induce in vivo maturation of leukaemic cells. It is suggested that induction of remission in AML patients by LD ARA-C may result from either differentiation of leukaemic blast cells, cytotoxicity to leukaemic blasts, or both mechanisms acting together.     

Developmentally regulated expression of the novel cancer anti-apoptosis gene survivin in human and mouse differentiation.

Inhibitors of programmed cell death (apoptosis) may regulate tissue differentiation and aberrantly promote cell survival in neoplasia. A novel apoptosis inhibitor of the IAP gene family, designated survivin, was recently found in all of the most common human cancers but not in normal, terminally differentiated adult tissues. The expression of survivin in embryonic and fetal development was investigated. Immunohistochemistry and in situ hybridization studies demonstrated strong expression of survivin in several apoptosis-regulated fetal tissues, including the stem cell layer of stratified epithelia, endocrine pancreas, and thymic medulla, with a pattern that did not overlap with that of another apoptosis inhibitor, bcl-2. A sequence-specific antibody to survivin immunoblotted a single approximately 16.5-kd survivin band in human fetal lung, liver, heart, kidney, and gastrointestinal tract. In mouse embryo, prominent and nearly ubiquitous distribution of survivin was found at embryonic day (E)11.5, whereas at E15 to -21, survivin expression was restricted to the distal bronchiolar epithelium of the lung and neural-crest-derived cells, including dorsal root ganglion neurons, hypophysis, and the choroid plexus. These data suggest that expression of survivin in embryonic and fetal development may contribute to tissue homeostasis and differentiation independently of bcl-2. Aberrations of this developmental pathway may result in prominent re-expression of survivin in neoplasia and abnormally prolonged cell viability.     

The role of long‐term physical exercise on performance and brain activation during the Stroop colour word task in fibromyalgia patients

The Stroop colour word test (SCWT) has been widely used to assess changes in cognitive performance such as processing speed, selective attention and the degree of automaticity. Moreover, the SCWT has proven to be a valuable tool to assess neuronal plasticity that is coupled to improvement in performance in clinical populations. In a previous study, we showed impaired cognitive processing during SCWT along with reduced task‐related activations in patients with fibromyalgia. In this study, we used SCWT and functional magnetic resonance imagingFMRI to investigate the effects of a 15‐week physical exercise intervention on cognitive performance, task‐related cortical activation and distraction‐induced analgesia (DIA) in patients with fibromyalgia and healthy controls. The exercise intervention yielded reduced fibromyalgia symptoms, improved cognitive processing and increased task‐related activation of amygdala, but no effect on DIA. Our results suggest beneficial effects of physical exercise on cognitive functioning in FM.     

In vitro functions of stromal cells from human and mouse bone marrow

Human fibroblastoid cell strains obtained from primary bone marrow cultures and continuous stromal cell lines recently derived from mouse bone marrow were studied. The incidence of fibroblastoid precursors (CFU-F) varied considerably in human bone marrow samples, and no differences could be detected between marrows from a group of myelodysplastic patients (age range 70-82 years) and groups of age-matched controls or younger individuals. A lack of direct correlation between initial clonogenicity and ultimate capacity of fibroblastoid cells to grow in continuous culture was observed in both the normal and the myelodysplastic groups. Despite the apparently normal clonogenicity of CFU-F in patients with myelodysplastic syndromes, some of these marrows failed to grow when subcultured. Normal fibroblastoid cells at 10(4) per culture exhibited myelopoietic activities when cocultured with fresh bone marrow cells. At higher concentrations, these cells inhibited myeloid colony formation. Fibroblastoid cells from only one out of four myelodysplastic patients examined exhibited comparable inhibitory activity. The specificity of the inhibitor(s) was demonstrated by the lack of effect of fibroblastoid cells from normal human bone marrow on the clonogenicity of mouse erythroleukemia cells. Moreover, human foreskin fibroblasts were devoid of such inhibitory activity. These functions of cultured stromal cells may correlate with some of their activities in the bone marrow microenvironment.