Non-radioactive in situ hybridization for the detection and monitoring of trisomy 12 in B-cell chronic lymphocytic leukaemia.
Non-radioactive in situ hybridization (NISH) with a chromosome 12-specific alpha satellite probe was performed on 20 patients with chronic lymphocytic leukaemia (CLL) with normal karyotype (15 cases) or with inadequate mitotic yield (5 cases) from mitogen-stimulated cultures. All patients had over 70% lymphocytes coexpressing the CD5/CD23 antigens. While less than 1% interphase nuclei showed three fluorescent spots in 16/20 patients, evidence of trisomy 12 in 15-25% interphase cells was detected in four patients. According to the FAB classification the diagnosis in these patients was typical B-CLL, stage III (Rai's staging system) in one case, CLL/PLL, stage II and III in two cases, PLL, stage III in one case. In order to confirm these results, NISH was repeated after 1 month in one patient and after 2 years in three patients. All patients had been treated with chemotherapy in the period between the two NISH experiments. In all cases a 1.8-3-fold increase of percentage of trisomic interphase cells was detected. These findings suggest that in B-CLL clones with trisomy 12 may have proliferative advantage over clonal B-lymphocyte without +12 and, possibly, that they may be more resistant to chemotherapy. We conclude that NISH is a sensitive technique allowing for the detection and monitoring of trisomy 12 in a fraction of B-CLL patients with normal karyotype or with no analysable mitoses despite employment of polyclonal B-cell mitogens.
Cuneo
A
A
Institute of Haematology, University of Ferrara, Italy.
Wlodarska
I
I
Sayed Aly
M
M
Piva
N
N
Carli
M G
MG
Fagioli
F
F
Tallarico
A
A
Pazzi
I
I
Ferrari
L
L
Cassiman
J J
JJ
D000368:Aged; D002881:Chromosomes, Human, Pair 12; D002999:Clone Cells; D015342:DNA Probes; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D007399:Interphase; D007621:Karyotyping; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000188:drug therapy / Q000235:genetics* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D008938:Mitosis; D009693:Nucleic Acid Hybridization; D013997:Time Factors; D014314:Trisomy
D015342:DNA Probes