Chromosomal abnormalities in a case of hairy cell leukaemia

Clonal chromosome rearrangements in hairy cell leukemia: personal experience and review of literature

Cytogenetic studies in hairy cell leukemia (HCL) are rare. In the present report, cytogenetic investigations were performed on marrow cells obtained from 21 HCL male patients with a mean age of 57 years and active disease. Karyotypic analysis was successful in 18 of the 21 patients, either at diagnosis or in relapse after treatment with IFNa. Clonal chromosome abnormalities were detected in eight of 18 cases. The chromosome most frequently involved in the rearranged karyotypes was chromosome 14. Results are discussed with respect to 79 abnormal HCL cases obtained from an extensive review of the literature from 1978 to 2000.

del(17)(q25) in a patient with hairy cell leukemia: a new clonal chromosome abnormality

Clonal chromosomal aberrations are reported in about 25% of the patients with hairy cell leukemia (HCL). No consistent cytogenetic abnormality has been described in HCL; most of the chromosomal changes found have been deletions and inversions, with the rare occurrence of translocations. While most of the chromosomal aberrations in HCL are common to the ones found in B cell chronic lymphocytic leukemia and other B cell lymphoproliferative disorders, there are also certain chromosomal changes that are not found in other B cell lymphoproliferative disorders. We present here a 63-year-old male patient with hairy cell leukemia with the clonal del(17)(q25), which has not previously been reported in HCL.

Establishment of a new cell line from a patient with hairy cell leukemia-Japanese variant

A cell line, JHC-2, was established from the peripheral blood of a patient with hairy cell leukemia (HCL)-Japanese variant. The JHC-2 cells have cytologic features similar to those of the original tumor cells. They displayed hairy cytoplasmic projections by phase contrast and scanning electron microscopy. The tartrate-resistant acid phosphatase reaction was weakly positive. The immunophenotype of the JHC-2 cells was CD5-, CD10-, CD11c+/-, CD19+, CD21+, CD23+, CD24-, CD25+/-, CD38- and FMC-7+. The expression of surface immunoglobulin (IgG, kappa) and the configuration of Ig gene rearrangements in the JHC-2 cells were identical to those in the original leukemic cells, and the JHC-2 cells displayed trisomy 9 on cytogenetic examination. Southern blot analysis for the Epstein-Barr virus (EBV) genome showed that the JHC-2 cells contained the EBV genome, although the freshly isolated leukemic cells did not. These results indicate that the JHC-2 cell line is an EBV spontaneously transformed B cell line originating from HCL cells.

Cytogenetics in CLL and related disorders

Chromosome analysis of more than 1200 patients with chronic lymphocytic leukaemia reported to the International Working Party on Chromosomes in CLL and in the literature is analysed. Clonal chromosomal abnormalities are found in about half of the patients, and one third of those with clonal aberrations have trisomy 12, with or without additional changes. The most common structural abnormalities involve the long arm of chromosome 13, usually as deletions involving 13q14, the site of the retinoblastoma gene. Other recurrent abnormalities are deletions of the long arms of chromosome 11 and 6. 14q+ markers are frequent in patients at advanced stage, but are almost always within complex abnormalities. The number of clonal abnormalities in the CLL cells has a strong prognostic impact. Trisomy 12 as a single abnormality is an adverse prognostic sign, whereas patients with 13q abnormalities generally do comparatively well. Lymphoid leukaemia with monoclonal immunoglobulin secretion frequently involves clonal chromosomal abnormalities, and the type of change is similar to that seen in true CLL. In B cell prolymphocytic leukaemia, t(11;14) is a common finding, together with trisomy 12. T cell prolymphocytic leukaemia is characterized by an inversion of the long arm of chromosome 14, with breaks at q11 and q32, and trisomy of 8q, whereas large granular lymphocytic leukaemia has shown no consistent abnormality. Hairy cell leukaemia seems to involve a specific set of non-random chromosome abnormalities, such as inv(5)9.

New cell line from hairy-cell leukemia: confirmation of leukemic cell origin by karyotype and Ig gene analysis

A hairy-cell leukemia (HCL) line, BNBH-I, was established from the peripheral blood of a 40-year-old male patient with HCL in a relatively stable clinical phase after splenectomy. The cells have since been growing continuously for more than 2 years. Their cell surface immunoglobulin (sIg) was identical with that found on the surface of freshly isolated leukemic cells, consisting of IgG-kappa. The BNBH-I cells were more mature than the original hairy cells in their degree of B-cell differentiation, as reflected by a decrease in sIg expression together with the appearance of some cytoplasmic Ig (cIg)+ cells, loss of EA gamma-rosette formation and reactivity with monoclonal antibody (MAb) FMC7, and an increase in the proportion of MAb PCA-I+ cells. The BNBH-I cells possessed the antigen recognized by Leu-M5, a highly specific MAb for HCL. Epstein-Barr virus nuclear antigen (EBNA) was present. Both the freshly isolated leukemic cells and the cell line had the 14q+ involving q32 chromosomal abnormality, and their Ig gene rearrangements were also identical. Following exposure to 12-O-tetradecanoylphorbol-13-acetate (TPA), both the freshly isolated leukemic cells and the BNBH-I cells adhered to culture dishes and extended long, thin processes, a phenomenon characteristic of HCL. These results indicate that the BNBH-I line was derived from the leukemic hairy cells.

Cytogenetic studies in hairy cell leukemia

Cytogenetic analyses were performed on cells from 17 patients with hairy cell leukemia stimulated with polyclonal B-cell activators (in 155 different cultures). No mitosis was obtained in samples from four cases (23.5%). Of 14 bone marrows, four (28.6%) showed mitoses, two with clonal abnormalities. All four samples from the spleen had mitoses with four clonal changes; eight of 13 (37.5%) blood samples had mitoses with three clonal changes. Of the polyclonal B-cell activators (PBA), lipopolysaccharide and protein A seemed to be effective for the detection of clonal abnormalities in hairy cell leukemia. Among the clonal aberrations, chromosomes #3, #10, and #17 were affected in two cases each; frequent numerical changes were monosomies of #10 and #17 and structural changes were deletions at band 3p21 (two cases), 6q-, and der(9)t(9;?)(p22;?). The chromosomal bands involved in structural changes were close to accepted constitutive fragile sites.

The 14q+ marker in hairy cell leukaemia. A cytogenetic study of 15 cases

Leukaemic cells from 19 patients with hairy cell leukaemia (HCL), characterised by morphological, immunological and ultrastructural criteria, were investigated for chromosome abnormalities after stimulation with B-cell mitogens (Pokeweed mitogen (PWM), lipopolysaccharide B and EBV). The cells from all cases had a B-cell phenotype and in each case only a single light chain type was expressed on the membrane of the cells. Only 15 patients with adequate metaphases are included in this study. Clonal chromosome abnormalities were observed in 12 patients of which five had a 14q + involving q32. Of the remaining 3 cases 1 had nonclonal abnormalities and 2 had normal karyotypes. The donor chromosomes were identified in 3 cases and were found to be 9, 18 and 22. An interstitial rearrangement of chromosome 14 involving band q22 was seen in 2 cases and a deletion of chromosome 14 at q24 in 1 case. Amongst other chromosome abnormalities 12p was involved in 4 cases, 12q in 2 cases and chromosomes 7 and 22 in 3 cases each. The significance of the abnormalities has been discussed in relation to sites of cellular oncogenes. Our study demonstrates that chromosome abnormalities common to other B-cell disorders are present in HCL.

Cytogenetic studies of stimulated lymphocytes in hairy cell leukemia

Using a sister chromatid differentiation (SCD) technique, cell cycle analysis in lymphocytes from two patients with hairy cell leukemia (HCL) revealed it to be similar to cell cycle progression of normal lymphocytes stimulated with lipopolysaccharide W from Escherichia coli 0.55:B5 (LPS). It appears that LPS can readily stimulate the leukemic cells of HCL into mitosis. In the two cases of B cell HCL studied, one (case 1) was revealed to have an abnormal clone with a missing chromosome #22 that was related to the production of lambda-chains.

Cytogenetic studies in patients with hairy cell leukemia

We performed cytogenetic studies on 58 patients with hairy cell leukemia (HCL) from 1975 to 1981. Analysable metaphase cells stained with Q-banding were obtained in 77 samples from 44 patients. Cells with abnormal chromosomes were found in both unstimulated and stimulated cultures of bone marrow and peripheral blood. Patients were classified in 6 groups. Group I, 2 patients with a clonal chromosome abnormality; group II, 13 patients with nonclonal structural abnormalities; group III, 5 patients with nonclonal numerical abnormalities; group IV, 19 patients with only a normal karyotype; group V, 15 patients with no or with fewer than 5 normal metaphase cells; group VI, 4 patients with questionable abnormal chromosomes. Common abnormalities were deletion of the long arm of No. 6 or +3 each in 3 patients, and +Y, +12 or +18 in 2 patients. Actuarial survival for each group was calculated from diagnosis and also from chromosome examination. The two patients with a clonal chromosome abnormality died within one year. Eight of 13 patients with nonclonal structural abnormalities died within 5 years after diagnosis, while none of 5 patients with nonclonal numerical abnormalities and 2 of 19 patients with normal chromosomes died within 5 years. The difference in the 5-year actuarial survival between patients with nonclonal abnormalities (groups II and III) and those with a normal karyotype was significant (p less than 0.05). The difference was more marked between patients with nonclonal structural abnormalities and those with a normal karyotype (p less than 0.01). Patients with nonclonal numerical abnormalities had a longer survival than those patients with nonclonal structural abnormalities (p less than 0.05). Thus, structural chromosome abnormalities in HCL may be a poor prognostic sign even when they are not clonal.