Browsing All Christie Publications by Subjects
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Chemotherapeutic agents used in the treatment of childhood malignancies have direct effects on growth plate chondrocyte proliferation.Short stature is one of the most well recorded long term sequelae for adult survivors of childhood malignancies. It has become increasingly apparent that cytotoxic chemotherapy, as well as craniospinal irradiation, has a major impact on growth, but there are virtually no studies which explore the mechanisms by which these cytotoxic drugs affect growth. We have used an in vitro system to investigate the direct effects of a range of chemotherapeutic agents on the proliferative responses of rat tibial growth plate chondrocytes, both in suspension and monolayer culture. The glucocorticoids and purine anti-metabolites reduced chondrocyte proliferation both in monolayer and suspension cultures and this resulted from an increase in cell doubling times with a concomittant reduction in the numbers of S phase cells. DNA damaging agents (e.g. actinomycin-D) were also able to reduce chondrocyte proliferation, both in monolayer and suspension culture. This, however, was the result of a cell cycle arrest and subsequent cell death. In our studies, methotrexate had no significant effect on the proliferative responses of the chondrocytes either in monolayer or suspension culture. These results indicate direct effects of a range of chemotherapeutic agents on the proliferative responses of growth plate chondrocytes. Both cytostatic and cytotoxic effects were observed although the impact of either the potential loss of cells from the proliferative pool during chondrocyte differentiation, or the reduction in the rate of chondrocyte turnover on long bone growth remains to be elucidated.
Effect of mitoxantrone on outcome of children with first relapse of acute lymphoblastic leukaemia (ALL R3): an open-label randomised trial.Although survival of children with acute lymphoblastic leukaemia has improved greatly in the past two decades, the outcome of those who relapse has remained static. We investigated the outcome of children with acute lymphoblastic leukaemia who relapsed on present therapeutic regimens.
Testicular histology after combination chemotherapy in childhood for acute lymphoblastic leukaemia.A study of testicular histology has been made in 44 boys treated with combination chemotherapy for acute lymphoblastic leukaemia. At the time of testicular biopsy 21 boys were still receiving cytotoxic drugs and 23 had completed their chemotherapy some time earlier. Evidence of leukaemic infiltration was seen in 5 (11%), interstitial fibrosis in 24 (55%), and basement-membrane thickening in 6 (14%). The mean tubular fertility index in the 44 biopsies was 50% of that in age-matched controls, and 18 of the biopsies had a severely depressed tubular fertility index (40% or less). Three variables had a highly significant effect on the tubular fertility index: previous therapy with cyclophosphamide or cytosine arabinoside (greater than 1 g/m2) depressed the tubular fertility index, whereas with increasing time after completion of chemotherapy the tubular fertility index improved. The prognosis for fertility in these subjects is not known. Long-term surveilance is necessary.