Evaluation of doxorubicin in combination with mafosfamide for in vitro elimination of myeloid and lymphoid tumor cells from human bone marrow.

In an attempt to improve in vitro pharmacological purging of autologous grafts, the ability of doxorubicin (DOX), alone and in combination with mafosfamide (AZ), to eliminate tumor cells from human bone marrow was assessed. HL60 and Raji cells were mixed with a 20-fold excess of normal marrow cells and were incubated either with DOX (0.4-3.2 micrograms/ml) for 1 h or AZ (20-140 micrograms/ml) for 30 min or both drugs sequentially. Cytotoxicity was evaluated on tumor cells and GM-CFU by clonogenic assays and on earlier hemopoietic progenitors by liquid long-term marrow cultures (LTMC) for 5 weeks. DOX at 3.2 micrograms/ml and AZ at 140 micrograms/ml spared 1.08 and 1.23% of GM-CFU respectively, and yielded similar tumor cell log-kills for HL60 cells (3.04 and 2.95) and Raji cells (3.24 and 3.40). With the combination of AZ and DOX, the best therapeutic index was observed when the cells were incubated with AZ prior to DOX. Under these conditions, AZ at 80 micrograms/ml together with DOX at 1.6 micrograms/ml significantly increased log-kill values for HL60 cells to 3.96 by a synergistic effect and for Raji cells to 3.85 by an additive effect. In LTMC, GM-CFU recovery after treatment with AZ alone and with the combination of AZ and DOX was 59.9 and 20.0%, respectively, while it was 7.9 and 2.9% at culture initiation. These results suggest that the purging efficiency of DOX is comparable to that of AZ and may be enhanced by combination with AZ.

CD5 negative B-cell chronic lymphocytic leukemia: clinical and biological features of 42 cases.

Chronic lymphocytic leukemia cell (CLL) usually (95%) express B-phenotype and the CD5 antigen which is usually present on the surface of normal T cells. However, among B CLL, 7 to 20% do not express CD5. The significance of the lack of CD5 expression remains unclear. We reviewed 42 consecutive CD5- B CLL seen in three French medical centers from 1985 to 1991 and compared them with 79 CD5+ B CLL. Immunophenotype studies were performed using indirect immunofluorescence under light microscopy as well as flow cytometry after 1988. B CLL was considered to be CD5 negative when less than 5% of mononuclear cells expressed CD5 after subtraction of the number of T-cells. Cases with CD5- B CLL had isolated splenomegaly more frequently (p = 2.10(-7)). They frequently expressed a higher level of surface immunoglobulin (S-Ig) or the switch mu/delta phenotype (p = 4.7 10(-2)). The median survival time was not reached but no significant difference between CD5 negative and positive B CLL was observed at the time of our data analysis (p = 0.97). Clinical presentation of CD5- B CLL seems to be different from other forms of B CLL. Although, no conclusion can be reached in terms of prognosis, CLL with low expression of CD5 should be regarded as a subtype of CLL with a different clinical presentation than CD5+ CLL.

Association between the SDF1-3'A allele and high levels of CD34(+) progenitor cells mobilized into peripheral blood in humans.

Some patients unexpectedly fail to mobilize sufficient numbers of haematopoietic progenitor cells (HPCs) into the peripheral blood for autologous transplantation. Considering the important role of the chemokine stromal cell-derived factor 1 (SDF-1) in HPC homing, we investigated a possible relationship between SDF1 gene polymorphism and HPC mobilization capacity in 63 patients with malignancy. Some 67% of the good mobilizers (> or = 50 CD34(+) cells/microl) and only 36% of the intermediate/poor mobilizers were SDF1-3'A allele carriers (P = 0.032). In multivariate analysis, the presence of the SDF1-3'A allele was the only factor predictive of good CD34(+) cell mobilization (P = 0.025). This is the first report showing the involvement of genetic factors for HPC mobilization in humans and suggests a significant role for SDF-1 in this process.

Early secondary acute myelogenous leukemia in breast cancer patients after treatment with mitoxantrone, cyclophosphamide, fluorouracil and radiation therapy.

BACKGROUND: The topoisomerase II-targeted drugs, epipodophyllotoxins and anthracyclines, have been shown to induce therapy-related AML (t-AML) characterized by a short latency period after chemotherapy, the absence of prior myelodysplastic syndrome and stereotyped chromosome aberrations. Few reports have been published on patients treated with the anthracenedione mitoxantrone which also targets topoisomerase II. We observed 10 cases of such t-AML over a 7-year-period in breast cancer patients treated with mitoxantrone combined with fluorouracil, cyclophosphamide and regional radiotherapy, and in three cases with vindesine. PATIENTS AND METHODS: We retrospectively analyzed patients referred to our hospital for AML with a past history of polychemotherapy for breast cancer, including mitoxantrone, either as adjuvant (8 patients)/neoadjuvant (1 patient) therapy or for metastatic disease (1 patient). We studied the probability of developing t-AML in a prospective series of 350 patients treated with an adjuvant FNC regimen (mitoxantrone, fluorouracil, cyclophosphamide) and radiation therapy. RESULTS: The median age was 45 years (range 35-67). t-AML developed 13-36 months (median 16) after beginning chemotherapy for breast cancer, and 4-28 months (median 10.5) after ending treatment. As described in t-AML following treatment with epipodophyllotoxins or anthracyclines, we found a majority of FAB M4, M5 and M3 phenotypes (7 of 10), and characteristic karyotype abnormalities that also can be found in de novo AML: breakpoint on chromosome 11q23 (3 patients), inv(16)(p13q22) (2 patients), t(15;17)(q22;q11) (1 patient), t(8;21)(q22;q22) (1 patient) and del(20q)(q11) (1 patient). The prognosis was poor. All patients died of AML shortly after diagnosis. Since two patients had been enrolled in a prospective trial for the treatment of breast cancer which included 350 patients, the probability of developing t-AML was calculated to be 0.7% from 25-40 months, using the Kaplan-Meier method (95%, confidence interval (95% CI): 0.1-4.5). CONCLUSIONS: The combination of mitoxantrone with cyclophosphamide, fluorouracil, and radiation therapy can induce t-AML, as with other topoisomerase II-targeted drugs. Despite a low incidence, the prognosis appears to be poor.