High-dose therapy with autologous bone marrow support as consolidation of remission in follicular lymphoma: long-term clinical and molecular follow-up.

PURPOSE: To evaluate the long-term results of high-dose therapy (HDT) in follicular lymphoma, with specific emphasis on the prognostic significance of polymerase chain reaction (PCR)-detectable Bcl-2/IgH rearrangements. PATIENTS AND METHODS: Between June 1985 and October 1995, 99 patients with follicular lymphoma received HDT as consolidation of second or subsequent remission. Bone marrow was treated in vitro with anti-B-cell antibodies and complement. RESULTS: Sixty-five patients remained alive, 49 treatment-failure free, with a median follow-up of 5.5 years (range, 1.5 to 12.5 years). Four "early" and 10 "late" deaths occurred from treatment-related causes; seven of the latter were due to secondary myelodysplasia (s-MDS) or secondary acute myeloblastic leukemia. Overall, 12 (12%) of the 99 patients developed s-MDS or acute myeloblastic leukemia. Kaplan-Meier estimates of freedom from recurrence (FFR) and survival rates at 5 years were 63% (95% confidence interval [CI], 52% to 72%) and 69% (95% CI, 58% to 78%), respectively. For all 99 patients, in multivariate analysis, absence of the Bcl-2/IgH rearrangement at the time of diagnosis (hazards ratio [HR], 0.39; P =.04) and three or fewer treatment episodes before HDT (HR, 0.03; P =.001) were significant prognostic factors for improved survival. For patients bearing Bcl-2/IgH rearrangements, in univariate and multivariate analyses, absence of a PCR-detectable Bcl-2/IgH rearrangement during follow-up was associated with a significantly lower risk of recurrence (adjusted HR, 0.13; P <.001) and death (HR, 0.25; P =.02), whereas the PCR status of the reinfused bone marrow did not correlate with outcome. CONCLUSION: Prolonged FFR can be achieved in patients with follicular lymphoma after HDT, but as yet there is no survival advantage compared with conventional treatment. These results confirm that elimination of cells bearing the Bcl-2/IgH rearrangement is highly desirable and should be attempted. The incidence of s-MDS is of increasing concern in this setting.

The cloning, mapping and expression of a novel gene, BRL, related to the AF10 leukaemia gene.

The MLL gene is reciprocally translocated with one of a number of different partner genes in a proportion of human acute leukaemias. The precise mechanism of oncogenic transformation is unclear since most of the partner genes encode unrelated proteins. However, two partner genes, AF10 and AF17 are related through the presence of a cysteine rich region and a leucine zipper. The identification of other proteins with these structures will aid our understanding of their role in normal and leukaemic cells. We report the cloning of a novel human gene (BRL) which encodes a protein containing a cysteine rich region related to that of AF10 and AF17 and is overall most closely related to the previously known protein BR140. BRL maps to chromosome 22q13 and shows high levels of expression in testis and several cell lines. The deduced protein sequence also contains a bromodomain, four potential LXXLL motifs and four predicted nuclear localization signals. A monoclonal antibody raised to a BRL peptide sequence confirmed its widespread expression as a 120 Kd protein and demonstrated localization to the nucleus within spermatocytes.

Tumour necrosis factor polymorphisms and susceptibility to follicular lymphoma.

Follicular lymphoma is characterized in 85% of patients by the presence of a t(14;18) chromosomal translocation that results in overproduction of BCL2. In this study the distribution of high and low expressing TNF alleles at the TNF (-308) and LTalpha (+252) polymorphic sites in 121 patients with follicular lymphoma and 88 control individuals has been analysed. A reduction in high expressing haplotypes in patients compared to normal controls was found (P = 0.055), with no significant difference observed in response rate or overall survival between patients with high or low expressing haplotypes. These results suggest that the TNF locus, or an adjacent locus within the MHC region, is an important genetic risk factor in this disease.

The expression of the ras p21 oncoprotein in the bone marrow smears of children with acute leukemia.

Point mutations of the ras genes have been detected in various hematologic malignancies. This genetic event may either occur in all malignant cells or be acquired by different subclones, which however, cannot be demonstrated adequately by analyzing only DNA derived from patient specimens. The availability of the ras p21 monoclonal antibody (MoAb) Y 13259 makes possible the direct study of the distribution of the ras gene product in human malignant cells. In this report the expression of the ras p21 oncoprotein in the bone marrow smears of 35 children with acute leukemia has been analyzed. The smears were treated with the MoAb Y 13259, biotinylated goat anti-rat IgG, streptavidin, peroxidase and stained with diaminobenzidine (DAB). The intensity of the staining was evaluated by two independent observers as negative or equivocal (-/+), moderate (+) or intense (++), by counting one thousand cells. Patients were also classified according to the percentage of the stained cells into four groups (0, I, II, III). It was found that 22/35 (63%) were (+) or (++) positive as follows: 11/21 (52%) with ALL CALLA (+), 2/2 ALL-B, 3/3 ALL-T and 6/9 AML. In Group 0 (none of the blasts was stained) were 13/35 (37%), as well as in Group I (1 to 25% of the blasts stained 1+ or 2+ positive), while in Group II (26 to 50% positive stained) 3/35 and in Group III (more than 51% stained) 6/35, all of which were AML (6/9). It is concluded that the immunohistochemical analysis of the ras p21 in blast cells of children with acute leukemia may demonstrate that ras gene expression in some subclones, the intensity and percentage of which may be of some clinical importance.